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  • 6551.
    Ameur, Yacin
    et al.
    KTH, School of Engineering Sciences (SCI), Mathematics (Dept.), Mathematics (Div.).
    Hedenmalm, Håkan
    KTH, School of Engineering Sciences (SCI), Mathematics (Dept.), Mathematics (Div.).
    Makarov, Nikolai
    Berezin Transform in Polynomial Bergman Spaces2010In: Communications on Pure and Applied Mathematics, ISSN 0010-3640, E-ISSN 1097-0312, Vol. 63, no 12, p. 1533-1584Article in journal (Refereed)
    Abstract [en]

    Fix a smooth weight function Q in the plane, subject to a growth condition from below Let K-m,K-n denote the reproducing kernel for the Hilbert space of analytic polynomials of degree at most n - 1 of finite L-2-norm with respect to the measure e-(mQ) dA Here dA is normalized area measure, and m is a positive real scaling parameter The (polynomial) Berezin measure dB(m,n)(< z0 >) (z) = K-m,K-n(z(0).z(0))(-1) vertical bar K-m,K-n(z.z(0))vertical bar(2)e(-mQ(z)) dA(z) for the point z(0) is a probability measure that defines the (polynomial) Berezin transform B-m,B-n f(z(0)) = integral(C) f dB(m,n)(< z0 >) for continuous f is an element of L-infinity (C). We analyze the semiclassical limit of the Berezin measure (and transform) as m -> +infinity while n = m tau + o(1), where tau is fixed, positive, and real We find that the Berezin measure for z(0) converges weak-star to the unit point mass at the point z(0) provided that Delta Q(z(0)) > 0 and that z(0) is contained in the interior of a compact set f(tau). defined as the coincidence set for an obstacle problem. As a refinement, we show that the appropriate local blowup of the Berezin measure converges to the standardized Gaussian measure in the plane For points z(0) is an element of C\f(tau), the Berezin measure cannot converge to the point mass at z(0) In the model case Q(z) = vertical bar z vertical bar(2), when f(tau) is a closed disk, we find that the Berezin measure instead converges to harmonic measure at z(0) relative to C\f(tau) Our results have applications to the study of the cigenvalues of random normal matrices The auxiliary results include weighted L-2-estimates for the equation partial derivative u = f when f is a suitable test function and the solution u is restricted by a polynomial growth bound at infinity.

  • 6552. Ameur, Yacin
    et al.
    Hedenmalm, Håkan
    KTH, School of Engineering Sciences (SCI), Mathematics (Dept.), Mathematics (Div.).
    Makarov, Nikolai
    FLUCTUATIONS OF EIGENVALUES OF RANDOM NORMAL MATRICES2011In: Duke mathematical journal, ISSN 0012-7094, E-ISSN 1547-7398, Vol. 159, no 1, p. 31-81Article in journal (Refereed)
    Abstract [en]

    In this article, we consider a fairly general potential in the plane and the corresponding Boltzmann-Gibbs distribution of eigenvalues of random normal matrices. As the order of the matrices tends to infinity, the eigenvalues condensate on a certain compact subset of the plane-the "droplet." We prove that fluctuations of linear statistics of eigenvalues of random normal matrices converge on compact subsets of the interior of the droplet to a Gaussian field, and we discuss various ramifications of this result.

  • 6553. Ameur, Yacin
    et al.
    Hedenmalm, Håkan
    KTH, School of Engineering Sciences (SCI), Mathematics (Dept.), Mathematics (Div.).
    Makarov, Nikolai
    Random normal matrices and ward identities2015In: Annals of Probability, ISSN 0091-1798, E-ISSN 2168-894X, Vol. 43, no 3, p. 1157-1201Article in journal (Refereed)
    Abstract [en]

    We consider the random normal matrix ensemble associated with a potential in the plane of sufficient growth near infinity. It is known that asymptotically as the order of the random matrix increases indefinitely, the eigenvalues approach a certain equilibrium density, given in terms of Frostman's solution to the minimum energy problem of weighted logarithmic potential theory. At a finer scale, we may consider fluctuations of eigenvalues about the equilibrium. In the present paper, we give the correction to the expectation of the fluctuations, and we show that the potential field of the corrected fluctuations converge on smooth test functions to a Gaussian free field with free boundary conditions on the droplet associated with the potential.

  • 6554.
    Ameur, Yacin
    et al.
    KTH, School of Engineering Sciences (SCI), Mathematics (Dept.).
    Kaijser, Sten
    Silvestrov, Serge
    Interpolation classes and matrix monotone functions2007In: Journal of operator theory, ISSN 0379-4024, E-ISSN 1841-7744, Vol. 57, no 2, p. 409-427Article in journal (Refereed)
    Abstract [en]

    An interpolation function of order n is a positive function -/+ on (0, infinity) such that vertical bar vertical bar -/+ (A)(1/2) T -/+ (A)-(1/2) vertical bar vertical bar <= max(vertical bar vertical bar T vertical bar vertical bar, vertical bar A(1/2)TA(-1/2) vertical bar vertical bar) for all n x ii matrices T and A such that A is positive definite. By a theorem of Donoghue, the class C-n of interpolation functions of order n coincides with the class of functions -/+ such that for each n-subset S = {lambda i}(n)(i=1)of (0,infinity) there exists a positive Pick function h on (0, co) interpolating -/+ at S. This note comprises a study of the classes C-n and their relations to matrix monotone functions of finite order. We also consider interpolation functions on general unital C*-algebras.

  • 6555. Amezaga, J.
    et al.
    Baresel, C.
    Destouni, G.
    Göbel, J.
    Gren, I.-M.
    Hannerz, F.
    Larsén, L.
    Loredo, J.
    Malmström, Maria
    KTH, Superseded Departments (pre-2005), Chemical Engineering and Technology.
    Nuttall, C.
    Santamaria, L.
    Veselie, M.
    Wolkersdorfer, C.
    Younger, P.
    Mining Impacts on the Fresh Water Environment: Technical and Managerial Guidelines for Catchment-Focused Remediation2004In: Mine Water and the Environment, ISSN 1025-9112, E-ISSN 1616-1068, Vol. S23, no 1, p. 1-80Article in journal (Refereed)
  • 6556.
    Amezcua Hidalgo, Ramon Andres
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Integrated Product Development.
    Towards Understanding the “User of the Future”2019Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    A fast-moving technological landscape is driving companies of today to constantly search for the solutions of tomorrow. As a result, companies are constantly searching for the next big thing and speculating on possible futures. Across multiple industries, it is easy to find concepts, workshops, hackathons, and marketing campaigns that address the concept of the future. With themes titled as "The future of ..."(be it medicine, food, manufacturing, sports, etc.) or "... of the future" (be it cars interiors, homes, transportation, nutrition, etc.), companies try to reimagine products and services for a speculative future. Design practice plays a large role in this movement. However, a specific contemporary global phenomenon, the Aging Populations, is surfacing important limitations to user-centred design. These limitations are resulting in unsustainable practices and negative connotations in design solutions that lead to Ageism. Furthermore, user-centred design processes are faced with the challenge of creating proposals that are limited by what could be misconceptions and prejudices based on personal knowledge. Since these proposals are conceived by present factors, needs and users, design is hence fringed by temporal positioning. The combination of these factors can lead to ideas of the future that may not be adequate or accurate for both an uncertain future, and the people that might participate in it.

    One may ask then, when identifying new opportunities, or when designing new products, what characteristics should be considered in the product development process that will remain stable and continuous in the future? This thesis explores this challenge. Resulting in a theoretically developed framework that helps design practitioners to understand the context that people may interact with in the future. Based on a Practice-Oriented Design approach, this thesis proposes a Transgenerational Practice Distillation Process that results in a Transgenerational Practice Unit, which aims at understanding the context in which the “Users of the Future” will interact with products and services. Then, by studying the practice of eating in a Quick Service Restaurant (QSR) in Tokyo with people with ages 60 to 80, the proposed framework explores how long-lasting contextual elements can be found through participatory design techniques. The output of the proposed framework consisted of stimulating material for creative processes that helped product innovation professionals in reimagining the way restaurants can be designed.

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  • 6557. Amft, Martin
    et al.
    Johansson, Börje
    KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering, Applied Material Physics.
    Skorodumova, Natalia V.
    KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering, Applied Material Physics.
    Influence of the cluster dimensionality on the binding behavior of CO and O(2) on Au(13)2012In: Journal of Chemical Physics, ISSN 0021-9606, E-ISSN 1089-7690, Vol. 136, no 2, p. 024312-Article in journal (Refereed)
    Abstract [en]

    We present an ab initio density functional theory study of the binding behavior of CO and O(2) molecules to two-and three-dimensional isomers of Au(13) in order to investigate the potential catalytic activity of this cluster towards low-temperature CO oxidation. First, we scanned the potential energy surface of Au(13) and studied the effect of spin-orbit coupling on the relative stabilities of the 21 isomers we identified. While spin-orbit coupling increases the stability of the three-dimensional more than the two-dimensional isomers, the ground state structure at 0 K remains planar. Second, we systematically studied the binding of CO and O(2) molecules onto the planar and three-dimensional structures lowest in energy. We find that the isomer dimensionality has little effect on the binding of CO to Au(13). O(2), on the other hand, binds significantly to the three-dimensional isomer only. The simultaneous binding of multiple CO molecules decreases the binding energy per molecule. Still, the CO binding remains stronger than the O(2) binding. We did not find a synergetic effect due to the co-adsorption of both molecular species. On the three-dimensional isomer, we find O(2) dissociation to be exothermic with an dissociation barrier of 1.44 eV.

  • 6558.
    Amft, Martin
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering, Multiscale Materials Modelling.
    Walle, L. E.
    Ragazzon, D.
    Borg, A.
    Uvdal, P.
    Skorodumova, Natalia V.
    KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering, Multiscale Materials Modelling.
    Sandell, A.
    A Molecular Mechanism for the Water-Hydroxyl Balance during Wetting of TiO22013In: The Journal of Physical Chemistry C, ISSN 1932-7447, E-ISSN 1932-7455, Vol. 117, no 33, p. 17078-17083Article in journal (Refereed)
    Abstract [en]

    We show that the formation of the wetting layer and the experimentally observed continuous shift of the H2O-OH balance toward molecular water at increasing coverage on a TiO2(110) surface can be rationalized on a molecular level. The mechanism is based on the initial formation of stable hydroxyl pairs, a repulsive interaction between these pairs, and an attractive interaction with respect to water molecules. The experimental data are obtained by synchrotron radiation photoelectron spectroscopy and interpreted with the aid of density functional theory calculations and Monte Carlo simulations.

  • 6559.
    Amgren, Pontus
    et al.
    KTH, School of Electrical Engineering and Computer Science (EECS).
    Olausson, Emil
    KTH, School of Electrical Engineering and Computer Science (EECS).
    Developing Guidelines for Structured Process Data Transfer2023Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Today, society is ever-increasing in its use of technology and computers. The increase in technology creates a need for different programming languages with unique properties. The creation of a system may require multiple languages for multiple processes that need to transfer data between one another. There are several solutions for sharing data between processes with their respective strengths and weaknesses. The differences create a problem of needing to understand the data transfer solutions to use them effectively. This thesis addresses the problem of there not existing any guidelines for data transfer solutions. The purpose is to create guidelines for choosing a data transfer solution. The goal is to help software developers find a data transfer solution that fits their needs. The thesis is meant to inform and contribute to the understanding of possible solutions for sharing data between processes. A literature study and practical study were needed to get that understanding. The literature study was conducted to understand the solutions and to be able to compare them. After that, a practical study was performed to work with the solutions and gain experience. The study was meant to gain measurements for later comparisons of data transfer solutions. The measurements followed the comparative criteria of speed , resource usage , and language support . The result was the creation of guidelines that displayed different scenarios based on the comparative criteria. For each situation, there was a recommendation of solutions that would help in the given situation. These results accomplished the goal and purpose by providing guidelines that could help software developers choose a data transfer solution.

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  • 6560.
    Amighi, Afshin
    KTH, School of Computer Science and Communication (CSC).
    Flow Graph Extraction for Modular Verification of Java Programs.2011Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The starting point for the project is a framework for compositional program verification based on program flow graphs, an abstraction of program control flow giving rise to an over-approximation of the source code behavior. Flow graph extraction for modular verification should allow the independent extraction of flow graphs of subsystems or modules. Furthermore, the composition of the flow graphs of the modules should give a safe approximation of the complete program flow graph. The existing tools for flow graph extraction are not flexible enough for modular purposes, since they typically assume that they are given a complete program.

    The goal of this study is the formal definition and implementation of modular flow graph extraction. In this project a formal translation from Java programs to target flow graph is specified. Then based on an operational semantics for the source language and for flow graphs, the correctness of the translation is proved. Flow graph extraction has to respect the modularity of programs, which is the main contribution of the work. Finally, a tool is developed based on specification of the translation.

  • 6561.
    Amighi, Afshin
    et al.
    University of Twente.
    de Carvalho Gomes, Pedro
    KTH, School of Computer Science and Communication (CSC), Theoretical Computer Science, TCS.
    Gurov, Dilian
    KTH, School of Computer Science and Communication (CSC), Theoretical Computer Science, TCS.
    Huisman, Marieke
    University of Twente.
    Provably Correct Control Flow Graphs from Java Bytecode Programs with Exceptions2016In: International Journal on Software Tools for Technology Transfer, ISSN 1433-2779, E-ISSN 1433-2787, ISSN 1433-2779, Vol. 18, no 6, p. 653-684Article in journal (Refereed)
    Abstract [en]

    We present an algorithm for extracting control flow graphs from Java bytecode that captures normal as well as exceptional control flow. We prove its correctness, in the sense that the behaviour of the extracted control flow graph is a sound over-approximation of the behaviour of the original program. This makes control flow graphs suitable for performing various static analyses, such as model checking of temporal safety properties.Analyzing exceptional control flow for Java bytecode is difficult because of the stack-based nature of the language. We therefore develop the extraction in two stages. In the first, we abstract away from the complications arising from exceptional flows, and relativize the extraction on an oracle that is able to look into the stack and predict the exceptions that can be raised at each instruction. This idealized algorithm provides a specification for concrete extraction algorithms, which have to provide a suitable implementation for the oracle. We prove correctness of the idealized algorithm by means of behavioural simulation.In the second stage, we develop a concrete extraction algorithm that consists of two phases. In the first phase, the program is transformed into a BIR program, a stack-less intermediate representation of Java bytecode, from which the control flow graph is extracted in the second phase. We use this intermediate format because it provides the information needed to implement the oracle, and since it gives rise to more compact graphs. We show that the behaviour of the control flow graph extracted via the intermediate representation is a sound over-approximation of the behaviour of the graph extracted by the direct, idealized algorithm, and thus of the original program. The concrete extraction algorithm is implemented as the ConFlEx tool. A number of test cases are performed to evaluate the efficiency of the algorithm.

  • 6562.
    Amighi, Afshin
    et al.
    University of Twente.
    de Carvalho Gomes, Pedro
    KTH, School of Computer Science and Communication (CSC), Theoretical Computer Science, TCS.
    Gurov, Dilian
    KTH, School of Computer Science and Communication (CSC), Theoretical Computer Science, TCS.
    Huisman, Marieke
    University of Twente.
    Provably Correct Control-Flow Graphs from Java Programs with Exceptions2012Report (Other academic)
    Abstract [en]

    We present an algorithm to extract flow graphs from Java bytecode, including exceptional control flows. We prove its correctness, meaning that the behavior of the extracted control-flow graph is a sound over-approximation of the behavior of the original program. Thus any safety property that holds for the extracted control-flow graph also holds for the original program. This makes control-flow graphs suitable for performing various static analyses, such as model checking.The extraction is performed in two phases. In the first phase the program is transformed into a BIR program, a stack-less intermediate representation of Java bytecode, from which the control-flow graph is extracted in the second phase. We use this intermediate format because it results in compact flow graphs, with provably correct exceptional control flow. To prove the correctness of the two-phase extraction, we also define an idealized extraction algorithm, whose correctness can be proven directly. Then we show that the behavior of the control-flow graph extracted via the intermediate representation is an over-approximation of the behavior of the directly extracted graphs, and thus of the original program. We implemented the indirect extraction as the CFGEx tool and performed several test-cases to show the efficiency of the algorithm.

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  • 6563.
    Amighi, Afshin
    et al.
    University of Twente.
    de Carvalho Gomes, Pedro
    KTH, School of Computer Science and Communication (CSC), Theoretical Computer Science, TCS.
    Gurov, Dilian
    KTH, School of Computer Science and Communication (CSC), Theoretical Computer Science, TCS.
    Huisman, Marieke
    University of Twente.
    Sound Control-Flow Graph Extraction for Java Programs with Exceptions2012In: Software Engineering and Formal Methods: 10th International Conference, SEFM 2012, Thessaloniki, Greece, October 1-5, 2012. Proceedings, Springer Berlin/Heidelberg, 2012, p. 33-47Conference paper (Refereed)
    Abstract [en]

    We present an algorithm to extract control-flow graphs from Java bytecode, considering exceptional flows. We then establish its correctness: the behavior of the extracted graphs is shown to be a sound over-approximation of the behavior of the original programs. Thus, any temporal safety property that holds for the extracted control-flow graph also holds for the original program. This makes the extracted graphs suitable for performing various static analyses, in particular model checking. The extraction proceeds in two phases. First, we translate Java bytecode into BIR, a stack-less intermediate representation. The BIR transformation is developed as a module of Sawja, a novel static analysis framework for Java bytecode. Besides Sawja’s efficiency, the resulting intermediate representation is more compact than the original bytecode and provides an explicit representation of exceptions. These features make BIR a natural starting point for sound control-flow graph extraction. Next, we formally define the transformation from BIR to control-flow graphs, which (among other features) considers the propagation of uncaught exceptions within method calls. We prove the correctness of the two-phase extraction by suitably combining the properties of the two transformations with those of an idealized control-flow graph extraction algorithm, whose correctness has been proved directly. The control-flow graph extraction algorithm is implemented in the ConFlEx tool. A number of test-cases show the efficiency and the utility of the implementation.

  • 6564. Amighi, Afshin
    et al.
    de Carvalho Gomes, Pedro
    KTH, School of Computer Science and Communication (CSC), Theoretical Computer Science, TCS.
    Huisman, Marieke
    Provably Correct Control-Flow Graphs from Java Programs with Exceptions2011In: Formal Verification of Object-Oriented Software, 2011, Vol. 26, p. 31-48Conference paper (Refereed)
    Abstract [en]

    We present an algorithm to extract flow graphs from Java bytecode, focusing on exceptional control flows. We prove its correctness, meaning that the behaviour of the extracted control-flow graph is an over-approximation of the behaviour of the original program. Thus any safety property that holds for the extracted control-flow graph also holds for the original program. This makes control-flow graphs suitable for performing different static analyses. For precision and efficiency, the extraction is performed in two phases. In the first phase the program is transformed into a BIR program, where BIR is a stack-less intermediate representation of Java bytecode; in the second phase the control-flow graph is extracted from the BIR representation. To prove the correctness of the two-phase extraction, we also define a direct extraction algorithm, whose correctness can be proven immediately. Then we show that the behaviour of the control-flow graph extracted via the intermediate representation is an over-approximation of the behaviour of the directly extracted graphs, and thus of the original program.

  • 6565.
    Amilawangi, Dane
    KTH, School of Architecture and the Built Environment (ABE), Architecture, Lighting Design.
    Urban Dark Acupuncture for Darkness: Value of Darkness in Pedestrian Experience of Sudirman Street, Jakarta2020Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    As much as we thought about artificial lighting in planning of our urban nightscape, it is necessary to balance it with consideration regarding darkness. In response to the problems caused by artificial lighting; such as light pollution and disruption to human circadian rhythm, darkness should be seen as a value that brings balance for the environment. There are nine values of darkness in urban illumination; efficiency, sustainable, ecology, healthiness, happiness, connects to nature, stellar visibility, heritage & tradition, wonder & beauty (Stone, 2019). In Designing for Darkness, Stone (2019) described three concepts to bring darkness into urban illumination design; Incremental Darkening, Environmentally Responsive Lighting, and Urban (Dark) Acupuncture. Urban Acupuncture is an effort to revitalize area and its surroundings through intervention in the strategic key point. (Leiner, 2014). In terms of urban lighting, the concept of Urban (Dark) Acupuncture described as an attempt to accentuate a strategic location in a city with darkness (Stone, 2019). This master thesis aims to apply the Urban (Dark) Acupuncture concept into a conceptual lighting design proposal for Sudirman Street, Jakarta. Functioned as a Central Business District of Jakarta, Sudirman Street is considered as a strategic key point for the intervention. The design proposal will be focusing on pedestrian facility of the street, and final result will be evaluated by the user. Keywords: Urban Lighting, Urban Acupuncture, Light Pollution, Darkness 

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  • 6566.
    Amilon, Jesper
    KTH, School of Electrical Engineering and Computer Science (EECS).
    Automated inference of ACSL function contracts using TriCera2021Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This thesis explores synergies between deductive verification and model checking, by using the existing model checker TriCera to automatically infer specifications for the deductive verifier Frama-C. To accomplish this, a formal semantics is defined for a subset of ANSI C, extended with assume statements, called Csmall. Then, it is shown how a Hoare logic contract can be translated into statements in Csmall, and the defined formal semantics is used to prove that the translation is correct. Furthermore, it is shown that the translation can be applied also to a real specification language. This is done by defining a subset of ACSL, called ACSLsmall, and giving a formal semantics also for this. Lastly, two examples are provided showing that the theory developed in this thesis can be applied to automatically infer ACSL function contracts. 

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  • 6567.
    Amilon, Jesper
    et al.
    KTH, School of Electrical Engineering and Computer Science (EECS), Computer Science, Theoretical Computer Science, TCS.
    Esen, Zafer
    Gurov, Dilian
    KTH, School of Electrical Engineering and Computer Science (EECS), Computer Science, Theoretical Computer Science, TCS.
    Lidström, Christian
    KTH, School of Electrical Engineering and Computer Science (EECS), Computer Science, Theoretical Computer Science, TCS.
    Rümmer, Philipp
    An Exercise in Mind Reading: Automatic Contract Inference for Frama-C2024In: Guide to Software Verification with Frama-C: Core Components, Usages, and Applications, Springer Nature, 2024Chapter in book (Other academic)
  • 6568.
    Amilon, Jesper
    et al.
    KTH, School of Electrical Engineering and Computer Science (EECS), Computer Science, Theoretical Computer Science, TCS.
    Esen, Zafer
    Uppsala University, Uppsala, Sweden.
    Gurov, Dilian
    KTH, School of Electrical Engineering and Computer Science (EECS), Computer Science, Theoretical Computer Science, TCS.
    Lidström, Christian
    KTH, School of Electrical Engineering and Computer Science (EECS), Computer Science, Theoretical Computer Science, TCS.
    Rümmer, Philipp
    Uppsala University, Uppsala, Sweden; University of Regensburg, Regensburg, Germany.
    Automatic Program Instrumentation for Automatic Verification2023In: Computer Aided Verification: 35th International Conference, CAV 2023, Proceedings, Springer Nature , 2023, p. 281-304Conference paper (Refereed)
    Abstract [en]

    In deductive verification and software model checking, dealing with certain specification language constructs can be problematic when the back-end solver is not sufficiently powerful or lacks the required theories. One way to deal with this is to transform, for verification purposes, the program to an equivalent one not using the problematic constructs, and to reason about its correctness instead. In this paper, we propose instrumentation as a unifying verification paradigm that subsumes various existing ad-hoc approaches, has a clear formal correctness criterion, can be applied automatically, and can transfer back witnesses and counterexamples. We illustrate our approach on the automated verification of programs that involve quantification and aggregation operations over arrays, such as the maximum value or sum of the elements in a given segment of the array, which are known to be difficult to reason about automatically. We implement our approach in the MonoCera tool, which is tailored to the verification of programs with aggregation, and evaluate it on example programs, including SV-COMP programs.

  • 6569.
    Amilon, Jesper
    et al.
    KTH, School of Electrical Engineering and Computer Science (EECS), Computer Science, Theoretical Computer Science, TCS.
    Lidström, Christian
    KTH, School of Electrical Engineering and Computer Science (EECS), Computer Science, Theoretical Computer Science, TCS.
    Gurov, Dilian
    KTH, School of Electrical Engineering and Computer Science (EECS), Computer Science, Theoretical Computer Science, TCS.
    Deductive Verification Based Abstraction for Software Model Checking2022In: Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics), Springer Nature , 2022, Vol. 13701 LNCS, p. 7-28Conference paper (Refereed)
    Abstract [en]

    The research community working on formal software verification has historically evolved into two main camps, grouped around two verification methods that are typically referred to as Deductive Verification and Model Checking. In this paper, we present an approach that applies deductive verification to formally justify abstract models for model checking in the TLA framework. We present a proof-of-concept tool chain for C programs, based on Frama-C for deductive verification and TLA+ for model checking. As a theoretical foundation, we summarise a previously developed abstract contract theory as a framework for combining these two methods. Since the contract theory adheres to the principles of contract based design, this justifies the use of the approach in a real-world system design setting. We evaluate our approach on two case studies: a simple C program simulating opening and closing of files, as well as a C program based on real software from the automotive industry.

  • 6570.
    Amilon, Jesper
    et al.
    KTH, School of Electrical Engineering and Computer Science (EECS).
    Lindeberg, Axel
    KTH, School of Electrical Engineering and Computer Science (EECS).
    Verifying Temporal Properties Using Deductive Verifiers2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Formal verification is an area of theoretical computer science where mathematical logic is used to prove that a program behaves in a certain way. With the methods in formal verification, you can prove that the program follows some given specification and thereby behaves in the desired way. The area is largely split up into two distinct parts. One deals with how the program transforms data. This uses Hoare logic and deductive verification to prove that the program follows a given specification. The other part deals with temporal properties of the program, this uses temporal logic and model checkers.

    The two areas are today largely separated. This report builds on a framework by Alur and Chaudhuri [1] which proves temporal properties in a Hoare logic style reasoning. By using this framework, this report aims to check the viability of using it with deductive verifiers. Thereby bridging the gap between the two areas for formal verification.

    In conclusion, the report finds that it is certainly possible to prove temporal properties for C programs using Alur and Chaudhuri’s framework with deductive verifiers. In practical terms, though, it requires too much work to be feasible to use this framework by manually creating annotations for the deductive verifiers. In a small example program of 13 lines, proving a temporal property required around 50 extra lines of annotations. However, some parts of the annotation process could be automated with tooling support but to achieve full automation is probably not possible. This is partly due to ranking functions that the framework requires which, in general, are not easy to generate automatically.

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  • 6571.
    Amilon, Mattias
    KTH, School of Computer Science and Communication (CSC).
    Chatbot with common-sense database2015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In 1950 Alan Turing introduced the famous “Turing test” which tests if a machine can be as intelligent as a human by testing if it can communicate with a person in a “human” way. Inspired by this test, numerous so called chatbots, in the form of computer programs, that manage a written dialogue have been created. A so called commonsensedatabase consists of data that most humans would know andconsider as common knowledge, something that computers generally do not know very muchabout. This report describes the process of an attempt to implement a simple chatbot using the common-sense database ConceptNet. The behaviour, or the human-likeness, of this chatbot was then compared to that of the classic chatbot ELIZA and the 2008 Loebner prize winning chatbot Elbot, through a series of user tests. The results indicate that using a common-sense database for a chatbot shows some promisefor further investigation.

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  • 6572.
    Amin, Diyar
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Soil and Rock Mechanics.
    Triaxial testing of lime/cement stabilized clay: A comparison with unconfined compression tests2015Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This master thesis presents results from a laboratory study on a clay from Enköping which was stabilized with lime and clay. Isotropic consolidated undrained compressive tests were performed on samples and compared to unconfined compressive testing.

    The two methods have shown no difference in the evaluation of undrained shear strength. However the modulus of elasticity was shown to be much higher for the triaxial tests. For the unconfined compressive tests the relation between the undrained shear strength and secant modulus was within the range of 44-146. The equivalent for the triaxial tests was in the interval of 112-333. However no pattern was extinguishable between the two tests as this relation has varied between 1,0 to 3,5.

    A lower and higher back pressure was used during the triaxial testing. However, both back pressures have succeeded in saturating the sample. Results show that the back pressure has little effect on the results, as long as the sample has been fully saturated.

    In addition to this extension tests were performed on samples as well. The tests performed were isotropic consolidated undrained. However two different shearing methods were used. The first test was strain rate dependant while the second test was stress rate dependant. In the first test the vertical stress decreased while the radial stresses were kept constant, while in the other test the radial stresses increased while the vertical stress were kept constant.

    The undrained shear strength was compared to lime/cement column penetration tests in field. Results showed that tests in field show a much higher undrained shear strength than laboratory testing.

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  • 6573.
    Amin, Diyar
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering.
    Latif Ali, Haval
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering.
    Vinterträdgårdar ur ett byggperspektiv: En undersökning om byggandet av vinterträdgårdar2012Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The purpose of this of this essay is to explore the construction of a conservatory that is livable all

    year around. When you build a conservatory there are several factors that need to be regarded

    that usually are of no importance when you build a regular conservatory. The glassed facade

    needs to have a very good U-value and all the parts of the facade need to be isolated and the

    construction needs to prevent thermal bridges.

    In this essay we will start by looking at the shape of the conservatory. Due to the façade consists

    of glass the conservatory will need to have a good ratio between the area and the façade so that

    the heat losses will be at a minimum. However, due to the fact that one of the sides of the façade

    is connected to the warm house, you quickly realize that the shape of the conservatory is of no

    importance.

    There are two common ways to build a foundation for a conservatory, a molded concrete

    foundation and isolated wooden beams. The molded concrete foundation is usually

    recommended but if you have a difference in heights on the ground the wooden beams are a

    good solution. The frame of the conservatory usually consists of gluelam; however there are

    some exceptions where the frame consists of aluminum. It is very common for the roof of a

    conservatory to consist of polycarbonate which is a very good at isolating while the price is still

    relatively low. Depending on how much time of the year you want to spend in the conservatory

    the thickness of the polycarbonate while differ. It is recommended that the minimum thickness

    of the roof of a conservatory that is to be used all year round should be 32 mm.

    The price of the conservatory varies greatly depending on how much time of the year you want

    to use it. A regular conservatory can cost around 33 000 SEK for an area of 10,5 m

    2while the

    same conservatory would cost up to 127 000 SEK. The difference in price arises due to the fact

    that the demands on a conservatory are higher it is to be used all year round. While a regular

    conservatory might have a U-value of 6,7 W/(m

    2*K) the U-value of an all year round

    conservatory is 1,1 W/(m

    2*K). The biggest increase in price comes when you go from an almost

    all year round conservatory to an all year round conservatory. The U-value decreases with 31 %

    while the price increases with 152 %. This is probably due to the complex process of preventing

    thermal bridges by installing plastic between the aluminum profiles.

    In today’s market there are three different categories

    of facades: sliding facades, folding facades

    and fixed parties. Even within the different categories there are different facades, they vary

    depending on how many glasses they consist of. These differentiate in price, this price difference

    is directly correlated to how much of the facade that you can open. The more you can open, the

    more expensive the price is.

    Also, we examine two different ways of heating the room, stoves and floor heating. Floor heating

    is a popular alternative for all year round conservatories because they usually have a molded

    concrete foundation. It is rather difficult to install floor heating in isolated wooden beams.

    That is why we examine another alternative, stove that run on ethanol. Apart from the heat they

    also add an esthetic appeal.

    At the end of the essay we will design our own conservatory that is adapted to the house. The

    final price for the all year round conservatory lands at a whopping 313 300 SEK.

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  • 6574.
    Amin, H.
    et al.
    Univ Gävle, Fac Engn & Sustainable Dev, SE-80176 Gävle, Sweden..
    Bagherbandi, Mohammad
    KTH, School of Architecture and the Built Environment (ABE), Real Estate and Construction Management, Geodesy and Satellite Positioning. Univ Gävle, Fac Engn & Sustainable Dev, SE-80176 Gävle, Sweden.
    Sjöberg, Lars E.
    KTH, School of Architecture and the Built Environment (ABE), Real Estate and Construction Management, Geodesy and Satellite Positioning. Univ Gävle, Fac Engn & Sustainable Dev, SE-80176 Gävle, Sweden.
    Quantifying barystatic sea-level change from satellite altimetry, GRACE and Argo observations over 2005-20162020In: Advances in Space Research, ISSN 0273-1177, E-ISSN 1879-1948, Vol. 65, no 8, p. 1922-1940Article in journal (Refereed)
    Abstract [en]

    Time-varying spherical harmonic coefficients determined from the Gravity Recovery and Climate Experiment (GRACE) data provide a valuable source of information about the water mass exchange that is the main contributor to the Earth's gravity field changes within a period of less than several hundred years. Moreover, by measuring seawater temperature and salinity at different layers of ocean depth, Argo floats help to measure the steric component of global mean sea level (GMSL). In this study, we quantify the rate of barystatic sea-level change using both GRACE RL05 and RL06 monthly gravity field models and compare the results with estimates achieved from a GMSL budget closure approach. Our satellite altimetry-based results show a trend of 3.90 +/- 0.14 mm yr(-1) for the GMSL rise. About 35% or 1.29 +/- 0.07 mm yr(-1) of this rate is caused by the thermosteric contribution, while the remainder is mainly due to the barystatic contribution. Our results confirm that the choice of decorrelation filters does not play a significant role in quantifying the global barystatic sea-level change, and spatial filtering may not be needed. GRACE RL05 and RL06 solutions result in the barystatic sea-level change trends of 2.19 +/- 0.13 mm yr(-1) and 2.25 +/- 0.16 mm yr(-1), respectively. Accordingly, the residual trend, defined as the difference between the altimetry-derived GMSL and sum of the steric and barystatic components, amounts to 0.51 +/- 0.51 and 0.45 +/- 0.44 mm yr(-1) for RL05 and RL06-based barystatic sea-level changes, respectively, over January 2005 to December 2016. The exclusion of the halosteric component results in a lower residual trend of about 0.36 +/- 0.46 mm yr(-1) over the same period, which suggests a sea-level budget closed within the uncertainty. This could be a confirmation on a high level of salinity bias particularly after about 2015. Moreover, considering the assumption that the GRACE-based barystatic component includes all mass change signals, the rather large residual trend could be attributed to an additional contribution from the deep ocean, where salinity and temperature cannot be monitored by the current observing systems. The errors from various sources, including the model-based Glacial Isostatic Adjustment signal, independent estimation of geocenter motion that are not quantified in the GRACE solutions, as well as the uncertainty of the second degree of zonal spherical harmonic coefficients, are other possible contributors to the residual trend.

  • 6575.
    Amin, Hadi
    et al.
    Faculty of Engineering and Sustainable Development, University of Gävle, 80176, Gävle, Sweden.
    Sjöberg, Lars E.
    KTH, School of Architecture and the Built Environment (ABE), Real Estate and Construction Management, Geodesy and Satellite Positioning. Faculty of Engineering and Sustainable Development, University of Gävle, 80176, Gävle, Sweden.
    Bagherbandi, Mohammad
    KTH, School of Architecture and the Built Environment (ABE), Real Estate and Construction Management, Geodesy and Satellite Positioning. Faculty of Engineering and Sustainable Development, University of Gävle, 80176, Gävle, Sweden.
    A global vertical datum defined by the conventional geoid potential and the Earth ellipsoid parameters2019In: Journal of Geodesy, ISSN 0949-7714, E-ISSN 1432-1394, Vol. 93, no 10, p. 1943-1961Article in journal (Refereed)
    Abstract [en]

    The geoid, according to the classical Gauss-Listing definition, is, among infinite equipotential surfaces of the Earth's gravity field, the equipotential surface that in a least squares sense best fits the undisturbed mean sea level. This equipotential surface, except for its zero-degree harmonic, can be characterized using the Earth's global gravity models (GGM). Although, nowadays, satellite altimetry technique provides the absolute geoid height over oceans that can be used to calibrate the unknown zero-degree harmonic of the gravimetric geoid models, this technique cannot be utilized to estimate the geometric parameters of the mean Earth ellipsoid (MEE). The main objective of this study is to perform a joint estimation of W-0, which defines the zero datum of vertical coordinates, and the MEE parameters relying on a new approach and on the newest gravity field, mean sea surface and mean dynamic topography models. As our approach utilizes both satellite altimetry observations and a GGM model, we consider different aspects of the input data to evaluate the sensitivity of our estimations to the input data. Unlike previous studies, our results show that it is not sufficient to use only the satellite-component of a quasi-stationary GGM to estimate W-0. In addition, our results confirm a high sensitivity of the applied approach to the altimetry-based geoid heights, i.e., mean sea surface and mean dynamic topography models. Moreover, as W-0 should be considered a quasi-stationary parameter, we quantify the effect of time-dependent Earth's gravity field changes as well as the time-dependent sea level changes on the estimation of W-0. Our computations resulted in the geoid potential W-0 = 62636848.102 +/- 0.004 m(2) s(-2) and the semi-major and minor axes of the MEE, a = 6378137.678 +/- 0.0003 m and b = 6356752.964 +/- 0.0005 m, which are 0.678 and 0.650 m larger than those axes of GRS80 reference ellipsoid, respectively. Moreover, a new estimation for the geocentric gravitational constant was obtained as GM = (398600460.55 +/- 0.03) x 10(6) m(3) s(-2).

  • 6576.
    Amin, Hamad
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Real Estate and Construction Management.
    Al-Haddad, Hussein
    KTH, School of Architecture and the Built Environment (ABE), Real Estate and Construction Management.
    Ethics and responsibility within the construction industry2014Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    All people face moral choices, it can be in private life, work, school or daily life. There are often rules

    and laws that guide us and declare how we should act in a specific situation. But how should we act in

    the "gray zone”, where there are no

    clear guidelines and rules, where the boundaries between right and

    wrong are not so clear.

    Like other industries, the construction industry is subjected to moral problems, and it is not always

    obvious what is right and wrong. Ethics and responsibility have become more important in the

    construction industry in the last years. Today, people have higher demands on their work situation and

    are more likely to pay attention to irregularities. Many construction companies are working with

    ethical issues, and develop systems and strategies in order to achieve better ethical actions.

    The thesis is about ethics and responsibility in the construction industry. The thesis investigates

    problems and practical cases that have connections to ethical and moral issues. That has been done by

    choosing five different fields. These fields are “Environmental Threats”, “Gender”, “Security and

    accidents”, “Corruption”, and “Procurement and Tende

    r”. Each field consists of a background part

    where facts and information are presented, after this a case is presented that represents an ethical

    problem for each field.

    The study also investigates which factors that the construction industry should work with in order to

    achieve better ethical actions. This part is mainly based on interviews with researchers and people that

    are active in the construction industry.

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  • 6577.
    Amin, Nuhu
    et al.
    Int Ctr Diarrhoeal Dis Res Bangladesh Icddr B, Infect Dis Div, Dhaka, Bangladesh.;Univ Technol Sydney, Inst Sustainable Futures, 235 Jones St, Ultimo, NSW 2007, Australia..
    Haque, Rehnuma
    Int Ctr Diarrhoeal Dis Res Bangladesh Icddr B, Infect Dis Div, Dhaka, Bangladesh.;Stanford Univ, Sch Med, Stanford, CA USA..
    Rahman, Md. Ziaur
    Int Ctr Diarrhoeal Dis Res Bangladesh Icddr B, Infect Dis Div, Dhaka, Bangladesh..
    Rahman, Mohammed Ziaur
    Int Ctr Diarrhoeal Dis Res Bangladesh Icddr B, Infect Dis Div, Dhaka, Bangladesh..
    Mahmud, Zahid Hayat
    Int Ctr Diarrhoeal Dis Res Bangladesh Icddr B, Infect Dis Div, Dhaka, Bangladesh..
    Hasan, Rezaul
    Int Ctr Diarrhoeal Dis Res Bangladesh Icddr B, Infect Dis Div, Dhaka, Bangladesh..
    Islam, MD Tahmidul
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering. WaterAid, Dhaka, Bangladesh..
    Sarker, Protim
    Int Ctr Diarrhoeal Dis Res Bangladesh Icddr B, Infect Dis Div, Dhaka, Bangladesh..
    Sarker, Supriya
    Directorate Gen Hlth Serv DGHS, Dhaka, Bangladesh..
    Adnan, Shaikh Daud
    Directorate Gen Hlth Serv DGHS, Dhaka, Bangladesh..
    Akter, Nargis
    UNICEF, Water Sanitat & Hyg WASH Sect, Dhaka, Bangladesh..
    Johnston, Dara
    UNICEF, Water Sanitat & Hyg WASH Sect, Dhaka, Bangladesh..
    Rahman, Mahbubur
    Int Ctr Diarrhoeal Dis Res Bangladesh Icddr B, Infect Dis Div, Dhaka, Bangladesh.;Inst Epidemiol Dis Control & Res IEDCR, Dhaka, Bangladesh..
    Liu, Pengbo
    Emory Univ, Ctr Global Safe Water Sanitat & Hyg, Atlanta, GA USA..
    Wang, Yuke
    Emory Univ, Ctr Global Safe Water Sanitat & Hyg, Atlanta, GA USA..
    Shirin, Tahmina
    Inst Epidemiol Dis Control & Res IEDCR, Dhaka, Bangladesh..
    Bhattacharya, Prosun
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Dependency of sanitation infrastructure on the discharge of faecal coliform and SARS-CoV-2 viral RNA in wastewater from COVID and non-COVID hospitals in Dhaka, Bangladesh2023In: Science of the Total Environment, ISSN 0048-9697, E-ISSN 1879-1026, Vol. 867, article id 161424Article in journal (Refereed)
    Abstract [en]

    The detection of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) RNA in wastewater can be used as an indicator of the presence of SARS-CoV-2 infection in specific catchment areas. We conducted a hospital-based study to explore wastewater management in healthcare facilities and analyzed SARS-CoV-2 RNA in the hospital wastewater in Dhaka city during the Coronavirus disease (COVID-19) outbreak between September 2020-January 2021. We selected three COVID-hospitals, two non-COVID-hospitals, and one non-COVID-hospital with COVID wards, conducted spot-checks of the sanitation systems (i.e., toilets, drainage, and septic-tank), and collected 90 untreated wastewater effluent samples (68 from COVID and 22 from non-COVID hospitals). E. coli was detected using a membrane filtration technique and reported as colony forming unit (CFU). SARS-CoV-2 RNA was detected using the iTaq Universal Probes One-Step kit for RT-qPCR amplification of the SARS-CoV-2 ORF1ab and N gene targets and quantified for SARS-CoV-2 genome equivalent copies (GEC) per mL of sample. None of the six hospitals had a primary wastewater treatment facility; two COVID hospitals had functional septic tanks, and the rest of the hospitals had either broken onsite systems or no containment of wastewater. Overall, 100 % of wastewater samples were positive with a high concentration of E.coli (mean = 7.0 log10 CFU/100 mL). Overall, 67 % (60/90) samples were positive for SARS-CoV-2. The highest SARS-CoV-2 concentrations (median: 141 GEC/mL; range: 13-18,214) were detected in wastewater from COVID-hospitals, and in non-COVID-hospitals, the median SARS-CoV-2 concentration was 108 GEC/mL (range: 30-1829). Our results indicate that high concentrations of E. coli and SARS-CoV-2 were discharged through the hospital wastewa-ter (both COVID and non-COVID) without treatment into the ambient water bodies. Although there is no evidence for transmission of SARS-CoV-2 via wastewater, this study highlights the significant risk posed by wastewater from health care facilities in Dhaka for the many other diseases that are spread via faecal oral route. Hospitals in low-income settings could function as sentinel sites to monitor outbreaks through wastewater-based epidemiological surveillance systems. Hospitals should aim to adopt the appropriate wastewater treatment technologies to reduce the discharge of pathogens into the environment and mitigate environmental exposures.

  • 6578.
    Amin, Nuhu
    et al.
    Icddr, Dhaka, Bangladesh..
    Haque, Rehnuma
    Icddr, Dhaka, Bangladesh..
    Rahman, Md. Ziaur
    Icddr, Dhaka, Bangladesh..
    Rahman, Mohammed Ziaur
    Icddr, Dhaka, Bangladesh..
    Mahmud, Zahid Hayat
    Icddr, Dhaka, Bangladesh..
    Hasan, Rezaul
    Icddr, Dhaka, Bangladesh..
    Sarker, Supriya
    Directorate Gen Hlth Serv DGHS, Dhaka, Bangladesh..
    Akter, Nargis
    UNICEF, Dhaka, Bangladesh..
    Johnston, Dara
    UNICEF, Dhaka, Bangladesh..
    Rahman, Mahbubur
    Icddr, Dhaka, Bangladesh..
    Bhattacharya, Prosun
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Hospitals In Dhaka And Discharge Of Wastewater With High Sars-Cov-2 Viral Rna Genetic Loadings: An Assessment Of Potential Environmental Health Risk2021In: American Journal of Tropical Medicine and Hygiene, ISSN 0002-9637, E-ISSN 1476-1645, Vol. 105, no 5, p. 265-266Article in journal (Other academic)
  • 6579.
    Amin, Saurabh
    et al.
    MIT, Cambridge, MA 02139 USA..
    Johansson, Karl H.
    KTH, School of Electrical Engineering and Computer Science (EECS), Intelligent systems, Decision and Control Systems (Automatic Control).
    Preface to the Focused Issue on Dynamic Games in Cyber Security2019In: Dynamic Games and Applications, ISSN 2153-0785, E-ISSN 2153-0793, Vol. 9, no 4, p. 881-883Article in journal (Other academic)
  • 6580.
    Amin, Shoaib
    KTH, School of Electrical Engineering (EES), Signal Processing.
    Characterization and Linearization of Multi-band Multi-channel RF Power Amplifiers2017Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The World today is deeply transformed by the advancement in wireless technology. The envision of a smart society where interactions between physical and virtual dimensions of life are intertwined and where human interaction is mediated by machines, e.g., smart phones, demands increasingly more data traffic. This continual increase in data traffic requires re-designing of the wireless technologies for increased system capacity and flexibility. In this thesis, aspects related to behavioral modeling, characterization, and linearization of multi-channel/band power amplifiers (PAs) are discussed.

    When building a model of any system, it is advantageous to take into account the knowledge of the physics of the system and include into the model. This approach could help to improve the model performance. In this context, three novel behavioral models and DPD schemes for nonlinear MIMO transmitters are proposed.

    To model and compensate distortions in GaN based RF PAs in presence of long-term memory effects, novel models for SISO and concurrent dual-band PAs are proposed. These models are based on a fixed pole expansion technique and have infinite impulse response. They show substantial performance improvement. A behavioral model based on the physical knowledge of the concurrent dual-band PA is derived, and its performance is investigated both for behavioral modeling and compensation of nonlinear distortions.

    Two-tone characterization is a fingerprint method for the characterization of memory effects in dynamic nonlinear systems. In this context, two novel techniques are proposed. The first technique is a dual two-tone characterization technique to characterize the memory effects of self- and cross-modulation products in concurrent dual-band transmitter. The second technique is for the characterization and analysis of self- and cross-Volterra kernels of nonlinear 3x3 MIMO systems using three-tone signals.

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    spik
  • 6581.
    Amin, Shoaib Amin
    KTH, School of Electrical Engineering (EES), Signal Processing. University of Gävle, Sweden.
    Characterization and Linearization of Multi-channel RF Power Amplifiers2015Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    The demands for high data rates and broadband wireless access require the development of wireless systems that can support wide and multi-band signals. To deploy these signals, new radio frequency (RF) front-ends are required which impose new challenges in terms of power consumption efficiency and sources of distortion e.g., nonlinearity. These challenges are more pronounced in power amplifiers (PAs) that degrade the overall performance of the RF transmitter. Since it is difficult to optimize the linearity and efficiency characteristics of a PA simultaneously, a trade-off is needed. At high input power, a PA exhibits high efficiency at the expense of linearity. On the other hand, at low input power, a PA is linear at the expense of the efficiency. To achieve linearity and efficiency at the same time, digital pre-distortion (DPD) is often used to compensate for the PA nonlinearity at high input power. In case of multi-channel PAs, input and output signals of different channels interact with each other due to cross-talk. Therefore, these PAs exhibit different nonlinear behavior than the single-input single-output (SISO) PAs. The DPD techniques developed for SISO PAs do not result in adequate performance when used for multi-channel PAs. Hence, an accurate behavioral modeling is essential for the development of DPD for multi-channel RF PAs. In this thesis, we propose three novel behavioral models and DPD schemes for nonlinear multiple-input multiple-output (MIMO) transmitters in presence of cross-talk. A study of the source of cross-talk in MIMO transmitters have been investigated to derive simple and powerful modeling schemes. These models are extensions of a SISO generalized memory polynomial model. A comparative study with a previously published MIMO model is also presented. The effect of coherent and partially non-coherent signal generationon DPD performance is also highlighted. It is shown experimentally that with partially non-coherent signal generation, the performance of the DPD degrades compared to coherent signal generation. In context of multi-channel RF transmitters, PA behavioral models and DPD schemes suffer from a large number of model parameters with the increase in nonlinear order and memory depth. This growth leads to high complexity model identification and implementation. We have designed a DPD scheme for MIMO PAs using a sparse estimation technique for reducing model complexity. This technique also increases the numerical stability when linear least square estimation model identification is used. A method to characterize the memory effects in a nonlinear concurrent dual-band PAs is also presented. Compared to the SISO PAs, concurrent dual-band PAs are not only affected by intermodulation distortions but also by cross-modulation distortions. The characterization of memory effects inconcurrent dual-band transmitter is performed by injecting a two-tone test signal in each input channel of the transmitter. Asymmetric energy surfaces are introduced for the intermodulation and cross-modulation products, which can be used to identify the power and frequency regions where the memory effects are dominant.

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    Licentiate Thesis
  • 6582.
    Amin, Shoaib
    et al.
    KTH, School of Electrical Engineering (EES), Signal Processing. KTH, School of Electrical Engineering (EES), Centres, ACCESS Linnaeus Centre. University of Gävle, Sweden.
    Händel, Peter
    KTH, School of Electrical Engineering (EES), Signal Processing. KTH, School of Electrical Engineering (EES), Centres, ACCESS Linnaeus Centre.
    Rönnow, Daniel
    ATM, University of Gävle.
    Digital Predistortion of Single and Concurrent Dual BandRadio Frequency GaN Amplifiers with Strong NonlinearMemory Effects2017In: IEEE transactions on microwave theory and techniques, ISSN 0018-9480, E-ISSN 1557-9670, Vol. 65, no 7, p. 2453-2464Article in journal (Refereed)
    Abstract [en]

    Electrical anomalies due to trapping effects in gallium nitride (GaN) power amplifiers (PAs) give rise to long-term or strong memory effects. We propose novel models based on infinite impulse response fixed pole expansion techniques for the behavioral modeling and digital predistortion of single-input single-output (SISO) and concurrent dual-band GaN PAs. Experimental results show that the proposed models outperform the corresponding finite impulse response (FIR) models by up to 17 dB for the same number of model parameters. For the linearization of a SISO GaN PA, the proposed models give adjacent channel power ratios (ACPRs) that are 7-17 dB lower than the FIR models. For the concurrent dual-band case, the proposed models give ACPRs that are 9-14 dB lower than the FIR models.

  • 6583.
    Amin, Shoaib
    et al.
    KTH, School of Electrical Engineering (EES), Signal Processing. KTH, School of Electrical Engineering (EES), Centres, ACCESS Linnaeus Centre.
    Khan, Zain Ahmed
    KTH, School of Electrical Engineering (EES), Signal Processing. KTH, School of Electrical Engineering (EES), Centres, ACCESS Linnaeus Centre.
    Isaksson, Magnus
    Högskolan i Gävle.
    Händel, Peter
    KTH, School of Electrical Engineering (EES), Signal Processing. KTH, School of Electrical Engineering (EES), Centres, ACCESS Linnaeus Centre.
    Rönnow, Daniel
    Högskolan i Gävle.
    Concurrent Dual-band Power Amplifier Model Modification using Dual Two-Tone Test2016In: European Microwave Week 2016: "Microwaves Everywhere", EuMW 2016 - Conference Proceedings; 46th European Microwave Conference, EuMC 2016, Institute of Electrical and Electronics Engineers (IEEE), 2016, p. 186-189, article id 7824309Conference paper (Refereed)
    Abstract [en]

    A dual two-tone technique for the characterization of memory effects in concurrent dual-band transmitters is revisited to modify a 2D-DPD model for the linearization of concurrent dual-band transmitters. By taking into account the individual nonlinear memory effects of the self- and cross-kernels, a new2D modified digital pre-distortion (2D-MDPD) model is proposed,which not only supersedes the linearization performance but also reduces the computational complexity compared to the 2DDPDmodel in terms of a number of floating point operations(FLOPs). Experimental results show an improvement of 1.7 dBin normalized mean square error (NMSE) and a 58% reduction in the number of FLOPs.

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    amin_et_al
  • 6584.
    Amin, Shoaib
    et al.
    KTH, School of Electrical Engineering (EES), Signal Processing.
    Ladin, Per N.
    ATM, University of Gävle.
    Händel, Peter
    KTH, School of Electrical Engineering (EES), Signal Processing.
    Rönnow, Daniel
    ATM, University of Gävle.
    2D Extended Envelope Memory Polynomial Model forConcurrent Dual-band RF Transmitters2016In: International journal of microwave and wireless technologies, ISSN 1759-0795, E-ISSN 1759-0787Article in journal (Refereed)
    Abstract [en]

    The paper presents a 2D extended envelope memory polynomial (2D-EEMP) model for concurrent dual-band radio frequency (RF) power amplifiers (PAs). The model is derived based on the physical knowledge of a dual-band RF PA. The derived model contains cross-modulation terms not included in previously published models; these terms are found to be of importance for both behavioral modeling and digital pre-distortion (DPD). The performance of the derived model is evaluated both as the behavioral model and DPD, and the performance is compared with state-of-the-art2D-DPD and dual-band generalized memory polynomial (DB-GMP) models. Experimental result shows that the proposed model resulted in normalized mean square error (NMSE) of -51.7/-51.6dB and adjacent channel error power ratio (ACEPR) of -63.1/-63.4 dB, for channel 1/2, whereas the 2D-DPD resulted in the largest model error and DB-GMP resulted in model parameters that are 3 times more than those resulted with the proposed model with the same performance. As pre-distorter, the proposed model resulted in adjacent channel power ratio (ACPR) of -55.8/ -54.6 dB for channel 1/2 and is 7-10 dB lower than those resulted with the 2D-DPD model and2-4 dB lower compared to the DB-GMP model.

  • 6585.
    Amin, Shoaib
    et al.
    KTH, School of Electrical Engineering (EES), Signal Processing. KTH, School of Electrical Engineering (EES), Centres, ACCESS Linnaeus Centre. Högskolan i Gävle.
    Landin, Per
    Chalmers University of Technology.
    Händel, Peter
    KTH, School of Electrical Engineering (EES), Signal Processing. KTH, School of Electrical Engineering (EES), Centres, ACCESS Linnaeus Centre.
    Rönnow, Daniel
    Högskolan i Gävle.
    Behavioral modeling and linearization of crosstalk and memory effects in RF MIMO transmitters2014In: IEEE transactions on microwave theory and techniques, ISSN 0018-9480, E-ISSN 1557-9670, Vol. 62, no 4, p. 810-823Article in journal (Refereed)
    Abstract [en]

    This paper proposes three novel models for behavioral modeling and digital pre-distortion (DPD) of nonlinear 2 x 2 multiple-input multiple-output (MIMO) transmitters in the presence of crosstalk. The proposed models are extensions of the single-input single-output generalized memory polynomial model. Three types of crosstalk effects were studied and characterized as linear, nonlinear, and nonlinear & linear crosstalk. A comparative study was performed with previously published models for the linearization of crosstalk in a nonlinear 2 x 2 MIMO transmitter. The experiments indicate that, depending on the type of crosstalk, the selection of the correct model in the transmitter is necessary for behavioral modeling and sufficient DPD performance. The effects of coherent and partially noncoherent signal generation on the performance of DPD were also studied. For crosstalk levels of 30 dB, the difference in the normalized mean square error and adjacent channel power ratio was found to be 3-4 dB between coherent and partially noncoherent signal generation.

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    fulltext
  • 6586.
    Amin, Shoaib
    et al.
    KTH, School of Electrical Engineering (EES), Signal Processing. University of Gävle, Sweden.
    Landin, Per N.
    Händel, Peter
    KTH, School of Electrical Engineering (EES), Signal Processing.
    Rönnow, Daniel
    2D Extended envelope memory polynomial model for concurrent dual-band RF transmitters2017In: International journal of microwave and wireless technologies, ISSN 1759-0795, E-ISSN 1759-0787, Vol. 9, no 8, p. 1619-1627Article in journal (Refereed)
    Abstract [en]

    The paper presents a two-dimensional (2D) extended envelope memory polynomial model for concurrent dual-band radio frequency (RF) power amplifiers (PAs). The model is derived based on the physical knowledge of a dual-band RF PA. The derived model contains cross-modulation terms not included in previously published models; these terms are found to be of importance for both behavioral modeling and digital predistortion (DPD). The performance of the derived model is evaluated both as the behavioral model and DPD, and the performance is compared with state-of-the-art 2D-DPD and dual-band generalized memory polynomial (DB-GMP) models. Experimental result shows that the proposed model resulted in normalized mean square error of -51.7/-51.6 dB and adjacent channel error power ratio of -63.1/-63.4 dB, for channel 1/2, whereas the 2D-DPD resulted in the largest model error and DB-GMP resulted in model parameters that are three times more than those resulted with the proposed model with the same performance. As pre-distorter, the proposed model resulted in adjacent channel power ratio of -55.8/-54.6 dB for channel 1/2 and is 7-10 dB lower than those resulted with the 2D-DPD model and 2-4 dB lower compared with the DB-GMP model.

  • 6587. Amin, Shoaib
    et al.
    van Moer, Wendy
    Händel, Peter
    KTH, School of Electrical Engineering (EES), Information Science and Engineering.
    Ronnow, Daniel
    Rebuttal to "On Dual-Band Amplifications Using Dual Two-Tones Clarifications and Discussions"2017In: IEEE Transactions on Instrumentation and Measurement, ISSN 0018-9456, E-ISSN 1557-9662, Vol. 66, no 10, p. 2795-2797Article in journal (Refereed)
    Abstract [en]

    This rebuttal is to "On dual-band amplifications using dual two-tone: Clarifications and discussion." In the following, we provide our reply.

  • 6588.
    Amin, Shoaib
    et al.
    KTH, School of Electrical Engineering (EES), Signal Processing. University of Gävle, Sweden.
    Van Moer, Wendy
    Händel, Peter
    KTH, School of Electrical Engineering (EES), Signal Processing.
    Rönnow, Daniel
    Characterization of a Concurrent dual-band Power Amplifier using a dual-tone excitation signals2014In: IEEE Transactions on Instrumentation and Measurement, ISSN 0018-9456, E-ISSN 1557-9662Article in journal (Other academic)
  • 6589.
    Amin, Shoaib
    et al.
    KTH, School of Electrical Engineering (EES), Signal Processing.
    Van Moer, Wendy
    University of Gävle.
    Händel, Peter
    KTH, School of Electrical Engineering (EES), Signal Processing.
    Rönnow, Daniel
    University of Gävle.
    Characterization of concurrent dual-band Power Amplifiers using a dual two-tone excitation signal2015In: IEEE Transactions on Instrumentation and Measurement, ISSN 0018-9456, E-ISSN 1557-9662, no 99Article in journal (Refereed)
    Abstract [en]

    A method to characterize the memory effects in a nonlinear concurrent dual-band transmitter is presented. It is an extension of the conventional two tone test for power amplifiers to concurrent dual band transmitters. The output signal of a concurrent dual-band transmitter is affected not only by intermodulation products but also by cross-modulation products. In one frequency band, the transmitter is excited by a two tone signal which frequency separation is swept. In the second band the transmitter is concurrently excited by an other two tone signal with slightly wider frequency separation. The frequency difference of the two signals is fixed during the frequency sweep. The two tone test is made at different power levels. The upper and lower third-order inter- and cross-modulation products are measured. The asymmetry between the upper and lower third-order inter- and cross-modulation products are measures of the transmitter's memory effects. The measurement results show that the memory effects are more dominant in the third-order intermodulation products than in the cross modulation products. An error analysis and system calibration was performed and measurement results for two different devices are presented.

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    amin_et_al
  • 6590.
    Amin, Shoaib
    et al.
    KTH, School of Electrical Engineering (EES), Signal Processing.
    Zenteno, Efrain
    KTH, School of Electrical Engineering (EES), Signal Processing.
    Landin, Per
    Dept. Electronics, Mathematics and Natural Sciences, Faculty of Engineering and Sustainable Development,University of Gävle .
    Rönnow, Daniel
    Dept. Electronics, Mathematics and Natural Sciences, Faculty of Engineering and Sustainable Development,University of Gävle .
    Isaksson, Magnus
    Dept. Electronics, Mathematics and Natural Sciences, Faculty of Engineering and Sustainable Development,University of Gävle .
    Händel, Peter
    KTH, School of Electrical Engineering (EES), Signal Processing.
    Noise Impact on the Identification of DigitalPredistorter Parameters in the Indirect LearningArchitecture2012In: Swedish Communication Technologies Workshop (Swe-CTW), 2012, IEEE conference proceedings, 2012, p. 36-39Conference paper (Refereed)
    Abstract [en]

    The indirect learning architecture (ILA) is the mostused methodology for the identification of Digital Pre-distorter(DPD) functions for nonlinear systems, particularly for highpower amplifiers. The ILA principle works in black box modelingrelying on the inversion of input and output signals of thenonlinear system, such that the inverse is estimated. This paperpresents the impact of disturbances, such as noise in the DPDidentification. Experiments were performed with a state-of-artDoherty power amplifier intended for base station operationin current telecommunication wireless networks. As expected,a degradation in the performance of the DPD (measured innormalized mean square error (NMSE)) is found in our experiments.However, adjacent channel power ratio (ACPR) canbe a misleading figure of merit showing improvement in theperformance for wrongly estimated DPD functions.

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    fulltext
  • 6591.
    Amin, Yasar
    KTH, School of Information and Communication Technology (ICT), Electronic Systems. KTH, School of Information and Communication Technology (ICT), Centres, VinnExcellence Center for Intelligence in Paper and Packaging, iPACK.
    Printable Green RFID Antennas for Embedded Sensors2013Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    In the recent years, radio-frequency identification (RFID) technology has been widely integrated into modern society applications, ranging from barcode successor to retail supply chain, remote monitoring, detection and healthcare, for instance. In general, an RFID tag or transponder is composed of an antenna and an application-specific integrated circuit chip. In a passive UHF RFID system (which is the focus of presented research), the communication between the transponder tag and the reader is established by modulating the radar cross section (RCS) of the transponder tag. The need for flexible RFID tags has recently been increased enormously; particularly the RFID tags for the UHF band ensure the widest use but in the meantime face considerable challenges of cost, reliability and environmental friendliness.

    The multidimensional focus of the aforementioned research encompasses the production of low-cost and reliable RFID tags. The state-of-the-art fabrication methods and materials for proposed antennas are evaluated in order to surmount the hurdles for realization of flexible green electronics. Moreover, this work addresses the new rising issues interrelated to the field of economic and eco-friendly tags comprising of paper substrate. Paper substrates offer numerous advantages for manufacturing RFID tags, not only is paper extensively available, and inexpensive; it is lightweight, recyclable and can be rolled or folded into 3D configurations.

    The most important aspect of an RFID system's performance is the reading range. In this research several pivotal challenges for item-level tagging, are resolved by evolving novel structures of progressive meander line, quadrate bowtie and rounded corner bowtie antennas in order to maximize the reading distance with a prior selected microchip under the various constraints (such as limited antenna size, specific antenna impedance, radiation pattern requirements). This approach is rigorously evolved for the realization of innovative RFID tag antenna which has incorporated humidity sensor functionality along with calibration mechanism due to distinctiveness of its structural behavior which will be an optimal choice for future ubiquitous wireless sensor network (WSN) modules.

    The RFID market has grown in a two-dimensional trend, one side constitutes standalone RFID systems. On the other side, more ultramodern approach is paving its way, in which RFID needs to be integrated with broad operational array of distinct applications for performing different functions including sensors, navigation, broadcasting, and personal communication, to mention a few. Using different antennas to include all communication bands is a straightforward approach, but at the same time, it leads to increase cost, weight, more surface area for installation, and above all electromagnetic compatibility issues. The indicated predicament is solved by realization of proposed single wideband planar spirals and sinuous antennas which covers several bands from 0.8-3.0GHz. These antennas exhibit exceptional performance throughout the operational range of significance, thus paving the way for developing eco-friendly multi-module RF industrial solutions.

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    Yasar Amin PhD Thesis
  • 6592.
    Amin, Yasar
    et al.
    KTH, School of Information and Communication Technology (ICT), Centres, VinnExcellence Center for Intelligence in Paper and Packaging, iPACK. KTH, School of Information and Communication Technology (ICT), Electronic, Computer and Software Systems, ECS.
    Chen, Qiang
    KTH, School of Information and Communication Technology (ICT), Centres, VinnExcellence Center for Intelligence in Paper and Packaging, iPACK. KTH, School of Information and Communication Technology (ICT), Electronic, Computer and Software Systems, ECS.
    Shao, Botao
    KTH, School of Information and Communication Technology (ICT), Centres, VinnExcellence Center for Intelligence in Paper and Packaging, iPACK. KTH, School of Information and Communication Technology (ICT), Electronic, Computer and Software Systems, ECS.
    Hållstedt, Julius
    KTH, School of Information and Communication Technology (ICT), Centres, VinnExcellence Center for Intelligence in Paper and Packaging, iPACK.
    Tenhunen, Hannu
    KTH, School of Information and Communication Technology (ICT), Centres, VinnExcellence Center for Intelligence in Paper and Packaging, iPACK. KTH, School of Information and Communication Technology (ICT), Electronic, Computer and Software Systems, ECS.
    Zheng, Li-Rong
    KTH, School of Information and Communication Technology (ICT), Centres, VinnExcellence Center for Intelligence in Paper and Packaging, iPACK. KTH, School of Information and Communication Technology (ICT), Electronic, Computer and Software Systems, ECS.
    Design and Analysis of Efficient and Compact Antenna for Paper Based UHF RFID Tags2008In: ISAPE 2008: THE 8TH INTERNATIONAL SYMPOSIUM ON ANTENNAS, PROPAGATION AND EM THEORY, PROCEEDINGS, VOLS 1-3 / [ed] Su D; Yan Z, NEW YORK: IEEE , 2008, p. 62-65Conference paper (Refereed)
    Abstract [en]

    Paper substrate is one of the paramount nominees for Radio Frequency Identification (RFID) tags but at the same time it is extremely prone towards environmental changes. In this paper, antennas for UHF RFID tags on paper based substrate are investigated and analyzed for the first time to evaluate the effect of change in dielectric constant on the antenna parameters and performance. On the basis of analysis a concrete meander line antenna is proposed, designed and evaluated which has tremendous immunity towards variation in dielectric constant.

  • 6593.
    Amin, Yasar
    et al.
    KTH, School of Information and Communication Technology (ICT), Electronic Systems. KTH, School of Information and Communication Technology (ICT), Centres, VinnExcellence Center for Intelligence in Paper and Packaging, iPACK.
    Chen, Qiang
    KTH, School of Information and Communication Technology (ICT), Electronic Systems. KTH, School of Information and Communication Technology (ICT), Centres, VinnExcellence Center for Intelligence in Paper and Packaging, iPACK.
    Tenhunen, Hannu
    KTH, School of Information and Communication Technology (ICT), Electronic Systems. KTH, School of Information and Communication Technology (ICT), Centres, VinnExcellence Center for Intelligence in Paper and Packaging, iPACK.
    Zheng, Lirong
    KTH, School of Information and Communication Technology (ICT), Electronic Systems. KTH, School of Information and Communication Technology (ICT), Centres, VinnExcellence Center for Intelligence in Paper and Packaging, iPACK.
    Evolutionary Versatile Printable RFID Antennas For "Green" Electronics2012In: Journal Electromagnetic Waves and Applications, ISSN 0920-5071, E-ISSN 1569-3937, Vol. 26, no 2-3, p. 264-273Article in journal (Refereed)
    Abstract [en]

    The development of low cost directly printable RFID tag antennas is essential for item level tracking. We present evolutionary design approach to achieve robust extremely versatile RFID antennas on paper/flexible substrates which allow a simple integration directly on, e.g., paperboard in a roll-to-roll production line. Fully integrated printed tags for "green" electronics are designed for operability in frequencies 866-868 MHz & 902-928 MHz. We present benchmarking results for various challenges of antennas in terms of ruggedness, reliability and flexing performance.

  • 6594.
    Amin, Yasar
    et al.
    KTH, School of Information and Communication Technology (ICT), Electronic Systems. KTH, School of Information and Communication Technology (ICT), Centres, VinnExcellence Center for Intelligence in Paper and Packaging, iPACK.
    Chen, Qiang
    KTH, School of Information and Communication Technology (ICT), Electronic Systems. KTH, School of Information and Communication Technology (ICT), Centres, VinnExcellence Center for Intelligence in Paper and Packaging, iPACK.
    Tenhunen, Hannu
    KTH, School of Information and Communication Technology (ICT), Electronic Systems. KTH, School of Information and Communication Technology (ICT), Centres, VinnExcellence Center for Intelligence in Paper and Packaging, iPACK.
    Zheng, Li-Rong
    KTH, School of Information and Communication Technology (ICT), Electronic Systems. KTH, School of Information and Communication Technology (ICT), Centres, VinnExcellence Center for Intelligence in Paper and Packaging, iPACK.
    Performance-Optimized Quadrate Bowtie RFID Antennas For Cost-Effective and Eco-Friendly Industrial Applications2012In: Progress in Electromagnetics Research-PIER, ISSN 1559-8985, Vol. 126, p. 49-64Article in journal (Refereed)
    Abstract [en]

    Fully integrated printed RFID antennas show potential solution for item level labeling applications. In order to accommodate the antenna during the package printing process, it is vastly preferred that antenna structures are printed on paper substrates. However, the electromagnetic properties and thickness of paper substrates are susceptible to change due to various environmental effects. Thus, adequately consistent in performance and material insensitive printed Quadrate Bowtie RFID antennas are proposed. This paper presents an in-depth efficient optimization for high performance tag antenna designs for operability in frequencies 866-868MHz & 902-928MHz. It is demonstrated that the proposed antennas can tolerate a considerable variation in the permittivity on thin paper substrates, and present benchmarking results when n across metal and water containing objects.

  • 6595.
    Amin, Yasar
    et al.
    KTH, School of Information and Communication Technology (ICT), Electronic Systems. KTH, School of Information and Communication Technology (ICT), Centres, VinnExcellence Center for Intelligence in Paper and Packaging, iPACK.
    Chen, Qiang
    KTH, School of Information and Communication Technology (ICT), Electronic Systems. KTH, School of Information and Communication Technology (ICT), Centres, VinnExcellence Center for Intelligence in Paper and Packaging, iPACK.
    Zheng, Lirong
    KTH, School of Information and Communication Technology (ICT), Electronic Systems. KTH, School of Information and Communication Technology (ICT), Centres, VinnExcellence Center for Intelligence in Paper and Packaging, iPACK.
    Tenhunen, Hannu
    KTH, School of Information and Communication Technology (ICT), Electronic Systems. KTH, School of Information and Communication Technology (ICT), Centres, VinnExcellence Center for Intelligence in Paper and Packaging, iPACK.
    Design and Fabrication of Wideband Archimedean Spiral Antenna Based Ultra-Low Cost "Green" Modules for RFID Sensing and Wireless Applications2012In: Progress In Electromagnetics Research-PIER, ISSN 1559-8985, Vol. 130, p. 241-256Article in journal (Refereed)
    Abstract [en]

    A parametric analysis is performed for a wideband Archimedean spiral antenna in recognition of an emerging concept to integrate RFID along with several applications by using a single antenna. The antenna is fabricated using state-of-the-art inkjet printing technology on various commercially available paper substrates to provide the low-cost, flexible RF modules for the next generation of "green" electronics. The effects on electromagnetic characteristics of the planar Archimedean spiral antenna, due to the use of paper are investigated besides other parameters. The proposed antenna is evaluated and optimized for operational range from 0.8-3.0GHz. It exhibits exceptional coverage throughout numerous RFID ISM bands so do for other wireless applications.

  • 6596.
    Amin, Yasar
    et al.
    KTH, School of Information and Communication Technology (ICT), Electronic Systems. KTH, School of Information and Communication Technology (ICT), Centres, VinnExcellence Center for Intelligence in Paper and Packaging, iPACK.
    Chen, Qiang
    KTH, School of Information and Communication Technology (ICT), Electronic Systems. KTH, School of Information and Communication Technology (ICT), Centres, VinnExcellence Center for Intelligence in Paper and Packaging, iPACK.
    Zheng, Lirong
    KTH, School of Information and Communication Technology (ICT), Electronic Systems. KTH, School of Information and Communication Technology (ICT), Centres, VinnExcellence Center for Intelligence in Paper and Packaging, iPACK.
    Tenhunen, Hannu
    KTH, School of Information and Communication Technology (ICT), Electronic Systems. KTH, School of Information and Communication Technology (ICT), Centres, VinnExcellence Center for Intelligence in Paper and Packaging, iPACK.
    Development and Analysis of Flexible UHF RFID Antennas For "Green" Electronics2012In: Progress In Electromagnetics Research-PIER, ISSN 1070-4698, Vol. 130, p. 1-15Article in journal (Refereed)
    Abstract [en]

    In this paper, novel Bowtie antennas which cover complete UHF RFID band (860-960MHz), fabricated on various ultra-low-cost substrates using state-of-the-art printing technologies are investigated as an approach that aims to accommodate the antenna during the package printing process whilst faster production on commercially available paper. The proposed antenna structures are evaluated in reference to circuit and field concepts, to exhibit extreme degree of functional versatility. These antennas are developed to cater the variations which appear in electromagnetic properties and thickness of paper substrate due to various environmental effects. Computed (simulated) and well-agreed measurement results confirm a superior performance of the tag modules while stepping towards next generation of "green" tags.

  • 6597.
    Amin, Yasar
    et al.
    KTH, School of Information and Communication Technology (ICT), Electronic Systems.
    Chen, Qiang
    KTH, School of Information and Communication Technology (ICT), Electronic Systems. KTH, School of Information and Communication Technology (ICT), Centres, VinnExcellence Center for Intelligence in Paper and Packaging, iPACK.
    Zheng, Lirong
    KTH, School of Information and Communication Technology (ICT), Electronic Systems. KTH, School of Information and Communication Technology (ICT), Centres, VinnExcellence Center for Intelligence in Paper and Packaging, iPACK.
    Tenhunen, Hannu
    KTH, School of Information and Communication Technology (ICT), Electronic Systems. KTH, School of Information and Communication Technology (ICT), Centres, VinnExcellence Center for Intelligence in Paper and Packaging, iPACK.
    "Green" Wideband Log-Spiral Antenna for RFID Sensing and Wireless Applications2012In: Journal of Electromagnetic Waves and Applications, ISSN 0920-5071, Vol. 26, no 14-15, p. 2043-2050Article in journal (Refereed)
    Abstract [en]

    The novel idea of integrating RFID with sensors along with other wireless applications by using single tag antenna is implemented, by fabricating proposed antenna using state-of-the-art inkjet printing technology on commercially available paper substrates. For the first time, a parametric analysis is performed for realization of planar log-spiral antenna on paper for operational range from 0.8-3.0GHz, which also exhibits excellent coverage throughout numerous RFID ISM bands, and for other wireless applications. The ANSYS HFSS tool is used to design and predict the performance of the proposed antenna in terms of radiation pattern and input impedance.

  • 6598.
    Amin, Yasar
    et al.
    KTH, School of Information and Communication Technology (ICT), Electronic Systems. KTH, School of Information and Communication Technology (ICT), Centres, VinnExcellence Center for Intelligence in Paper and Packaging, iPACK.
    Chen, Qiang
    KTH, School of Information and Communication Technology (ICT), Electronic Systems. KTH, School of Information and Communication Technology (ICT), Centres, VinnExcellence Center for Intelligence in Paper and Packaging, iPACK.
    Zheng, Lirong
    KTH, School of Information and Communication Technology (ICT), Electronic Systems. KTH, School of Information and Communication Technology (ICT), Centres, VinnExcellence Center for Intelligence in Paper and Packaging, iPACK.
    Tenhunen, Hannu
    KTH, School of Information and Communication Technology (ICT), Electronic Systems. KTH, School of Information and Communication Technology (ICT), Centres, VinnExcellence Center for Intelligence in Paper and Packaging, iPACK.
    Two-arm Sinuous Antenna for RFID Ubiquitous Sensors and Wireless Applications2012In: Journal Electromagnetic Waves and Applications, ISSN 0920-5071, E-ISSN 1569-3937, Vol. 26, no 17-18, p. 2365-2371Article in journal (Refereed)
    Abstract [en]

    For the first time, two-arm planar sinuous antenna is demonstrated to realize the emerging concept of integrating RFID functionalities along with sensors and other wireless applications for "green" electronics. In-depth, parametric analysis is performed for the proposed antenna which is fabricated on a paper substrate using revolutionary inkjet printing technology to develop a system-level solution for ultra-low-cost mass production of multipurpose wireless tags in an approach that could be easily expanded to other microwave and wireless "cognition" applications. The proposed antenna exhibits excellent performance throughout several RFID ISM bands and for other wireless applications in its operational range from 0.8 to 3.0 GHz.

  • 6599.
    Amin, Yasar
    et al.
    KTH, School of Information and Communication Technology (ICT), Electronic Systems. KTH, School of Information and Communication Technology (ICT), Centres, VinnExcellence Center for Intelligence in Paper and Packaging, iPACK.
    Feng, Yi
    KTH, School of Information and Communication Technology (ICT), Electronic Systems. KTH, School of Information and Communication Technology (ICT), Centres, VinnExcellence Center for Intelligence in Paper and Packaging, iPACK.
    Chen, Qiang
    KTH, School of Information and Communication Technology (ICT), Electronic Systems. KTH, School of Information and Communication Technology (ICT), Centres, VinnExcellence Center for Intelligence in Paper and Packaging, iPACK.
    Zheng, Lirong
    KTH, School of Information and Communication Technology (ICT), Electronic Systems. KTH, School of Information and Communication Technology (ICT), Centres, VinnExcellence Center for Intelligence in Paper and Packaging, iPACK.
    Tenhunen, Hannu
    KTH, School of Information and Communication Technology (ICT), Electronic Systems. KTH, School of Information and Communication Technology (ICT), Centres, VinnExcellence Center for Intelligence in Paper and Packaging, iPACK.
    RFID antenna humidity sensor co-design for USN applications2013In: IEICE Electronics Express, E-ISSN 1349-2543, Vol. 10, no 4, p. 20130003-Article in journal (Refereed)
    Abstract [en]

    We demonstrate for the first time an RFID tag antenna which itself is humidity sensor and also provides calibration functionality. The antenna is comprised of T-matching network and horizontally meandered lines for impedance matching and reliable near-field communication. The novel contour design provides humidity sensing, and calibration functions whilst concurrently acts as a radiating element along with quadrangular capacitive tip-loading with covered middle portion for far-field communication. The inkjet printed prototypes of the antenna provide effective ambient humidity sensing while demonstrating stable RFID communication. The antenna has a compact size of 1.1 x 10.2 cm for 902-928MHz band.

  • 6600.
    Amin, Yasar
    et al.
    KTH, School of Information and Communication Technology (ICT), Centres, VinnExcellence Center for Intelligence in Paper and Packaging, iPACK. KTH, School of Information and Communication Technology (ICT), Electronic, Computer and Software Systems, ECS.
    Hållstedt, Julius
    KTH, School of Information and Communication Technology (ICT), Centres, VinnExcellence Center for Intelligence in Paper and Packaging, iPACK. KTH, School of Information and Communication Technology (ICT), Electronic, Computer and Software Systems, ECS.
    Prokkola, Satu
    Tenhunen, Hannu
    KTH, School of Information and Communication Technology (ICT), Centres, VinnExcellence Center for Intelligence in Paper and Packaging, iPACK. KTH, School of Information and Communication Technology (ICT), Electronic, Computer and Software Systems, ECS.
    Zheng, Li-Rong
    KTH, School of Information and Communication Technology (ICT), Centres, VinnExcellence Center for Intelligence in Paper and Packaging, iPACK. KTH, School of Information and Communication Technology (ICT), Electronic, Computer and Software Systems, ECS.
    Robust Flexible High Performance UHF RFID Tag Antenna2009In: 2009 11TH ELECTRONICS PACKAGING TECHNOLOGY CONFERENCE (EPTC 2009), NEW YORK: IEEE , 2009, p. 235-239Conference paper (Refereed)
    Abstract [en]

    This paper describes a novel Flexo, Screen and Inkjet printed rounded edges bowtie antenna with T-matching stubs on paper, Kapton (HN) and Teonex Q51 substrate. Paper is one of the paramount nominees for Radio Frequency Identification (RFID) tags, for the reason that it is one of the widely and the cheapest available substrates. Kapton (HN) and Teonex Q51 are distinguished for their flexibility and reliability. The antenna exhibits compact size with outstanding read range of 4 meters and complete coverage of UHF RFID band (860-960 MHz). The results show extreme immunity of versatile antenna against harsh environments. These antennas are flexible which give autonomy for their applications.

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