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  • 1.
    Aguilar, Antonio
    et al.
    Digital Enterprise Research Institute, National University of Ireland, Galway, Ireland.
    van der Putten, Wil
    Department of Medical Physics, University College Hospital Galway, Galway, Ireland .
    Maguire Jr., Gerald Q.
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Kommunikationssystem, CoS, Radio Systems Laboratory (RS Lab).
    Positive Patient Identification using RFID and Wireless  Networks2006Inngår i: Proceedings of the HISI 11th Annual Conference and Scientific Symposium, Dublin, Ireland, Dublin, Ireland, 2006Konferansepaper (Fagfellevurdert)
    Abstract [en]

    The increased focus on patient safety in hospitals has yielded a flood of new technologies and tools seeking to improve the quality of patient care at the point-of-care. Hospitals are complex institutions by nature, and are constantly challenged to improve the quality of healthcare delivered to patients while trying to reduce the rate of medical errors and improve patient safety. Here a simple mistake such as patient misidentification, specimen misidentification, wrong medication, or wrong blood transfusion can cause the loss of a patient's life. The focus of this paper is the implementation and evaluation of a handheld-based patient identification system that uses radio frequency identification (RFID) and 802.11b wireless networks to identify patients. In this approach, each patient is given a RFID wristband which contains demographic information (patient ID number, patient summary, hospital code) of the patient. A handheld device equipped with 802.11b wireless connectivity and a RFID reader is then used by the medical staff to read the patient's wristband and identify the patient. This work was carried out at the Department of Medical Physics and Bioengineering at the University College Hospital Galway, Ireland and in co-operation with the National University of Ireland, Galway.

  • 2.
    Ahlin, Lars
    et al.
    Swedish Defence Research Agency (FOI).
    Englund, Eva
    FOI.
    Jönsson, Christian
    FOI.
    Söderquist, Ingrid
    FOI.
    Zander, Jens
    KTH, Tidigare Institutioner, Signaler, sensorer och system.
    Maguire Jr., Gerald Q.
    KTH, Tidigare Institutioner, Teleinformatik.
    Automous Tactical Communications Possibilities and Problems1997Inngår i: MILCOM 97 Proceedings, 1997, s. 393-397Konferansepaper (Fagfellevurdert)
    Abstract [en]

    In the battlefield of the future, more and more information will be available for making decisions on a tactical level, provided that this information can be dispersed rapidly and accurately. As a consequence, advanced tactical decision support that now is limited to advanced platforms (e.g. combat aircrafts) will become available at a much lower level, ranging from different kinds of vehicles, down to the individual soldier by means of ultra-light weight ``wearable'' equipment.

    Establishing reliable wireless communications in such a large group of users with unprecidented bandwidth demands and requirements on survivability constitutes a considerable enginerring challenge. In the paper we will, after a short review of some existing approaches, investigate the specific engineering challenges and the fundamental limitations of such low level, autonomous communication systems. Further we give an example of a system architecture, harmonized with a proposed structure for third generation commercial wireless systems (e.g. UMTS). Our conclusions show that mainly distributed computing complexity, device power consumption and available bandwidth constitute the fundamental problems.

  • 3. Aitken, Candice L.
    et al.
    Gorniak, Richard J. T.
    New York University.
    Kramer, Elissa L.
    New York University.
    Noz, Marilyn E.
    New York University.
    Farrell, Eward J.
    IBM Research.
    Maguire Jr., Gerald Q.
    KTH, Tidigare Institutioner, Teleinformatik.
    Reddy, David P.
    Comparison of three methods used for fusion of SPECT-CT images of liver matastases1998Inngår i: Fusion98, International Conference on Multisource-Mulltisensor Information Fusion / [ed] Hamid R. Arabnia and Dongping (Daniel) Zhu, CSREA Press , 1998, s. 435-442Konferansepaper (Fagfellevurdert)
    Abstract [en]

    We compare three methods for fusing SPECT-CT images: ImageMatch - an automatic three-dimensional/two-dimensional method developed by Focus Imaging; IBM Visualization Data Explorer - a three-diemensional interactive method developed by Internation Business Machines, Inc.; and qsh - an interactive three-dimensional/two-dimensional method developed at New York University. While many fusion methods have proved successful for registering brain images, most methods have been less successful for thoracic and abdominal images. We use images of liver metastases obtained with a radiolabeled breast tumor-directed antibody to illustrate the strengths and weakness of the methods reviewed. The images used are typical clinical images from eigth patients. We conclude that an optimal image fusion program should combine the strengths of each of the methods reviewed.

  • 4. Aitken, Candice L.
    et al.
    Mahmoud, Faaiza
    McGuinness, Georgeann
    Kramer, Elissa L.
    Maguire, Gerald Q. Jr.
    KTH, Tidigare Institutioner, Mikroelektronik och informationsteknik, IMIT.
    Noz, Marilyn E.
    New York University.
    Tumor localization and image registration of F-18FDG coincidence detection scans with computed tomographic scans2002Inngår i: Clinical Nuclear Medicine, ISSN 0363-9762, E-ISSN 1536-0229, Vol. 27, nr 4, s. 275-282Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Purpose: The aim of this study was to determine the feasibility of registering routine clinical F-18 fluorodeoxyglucose (FDG) coincidence detection (CD) scans with computed tomographic (CT) scans for radiation treatment planning and case management. Methods: F-18 FDG CD and chest CT scans, performed in 10 randomly selected patients with confirmed or possible adenocarcinoma of the lung, were evaluated. The quality of the matches was verified by comparisons of the center-to-center distance between a region of interest (ROI) manually drawn on the CT slice and warped onto the CD slice with an ROI drawn manually directly on the CD slice. In addition, the overlap between the two ROIs was calculated. Results: All 10 F-18 FDG CD and CT scans were registered with good superimposition of soft tissue density on increased radionuclide activity. The center-to-center distance between the ROIs ranged from 0.29 mm to 8.08 mm, with an average center-to-center distance of 3.89 mm 2.42 mm (0.69 pixels +/- 0.34 pixels). The ROI overlap ranged from 77% to 99%, with an average of 90% +/- 5.6%. Conclusions: Although the use of F-18 FDG CD shows great promise for the identification of tumors, it shares the same drawbacks as those associated with radiolabeled monoclonal antibody SPECT and ligand-based positron emission tomographic scans in that anatomic markers are limited. This study shows that image registration is feasible and may improve the clinical relevance of CD images.

  • 5.
    Aitken, Candice L.
    et al.
    New York University.
    McGuinness, Georgeann
    New York University.
    Siddiqui, Faaiza
    New York University.
    Ton, Anthony
    New York University.
    Kramer, Elissa L
    New York University.
    Maguire Jr., Gerald Q.
    KTH, Tidigare Institutioner, Teleinformatik.
    Noz, Marilyn E.
    New York University, Department of Radiology.
    Tumor localization and image registration of 18-FDG SPECT scans with CT scans1999Inngår i: Journal of Nuclear Medicine, ISSN 0161-5505, E-ISSN 1535-5667, Vol. 40, nr 5, s. 290P-291PArtikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    PURPOSE:

    The aim of this study was to determine the feasibility of registering routine clinical F-18 fluorodeoxyglucose (FDG) coincidence detection (CD) scans with computed tomographic (CT) scans for radiation treatment planning and case management.

    METHODS:

    F-18 FDG CD and chest CT scans, performed in 10 randomly selected patients with confirmed or possible adenocarcinoma of the lung, were evaluated. The quality of the matches was verified by comparisons of the center-to-center distance between a region of interest (ROI) manually drawn on the CT slice and warped onto the CD slice with an ROI drawn manually directly on the CD slice. In addition, the overlap between the two ROIs was calculated.

    RESULTS:

    All 10 F-18 FDG CD and CT scans were registered with good superimposition of soft tissue density on increased radionuclide activity. The center-to-center distance between the ROIs ranged from 0.29 mm to 8.08 mm, with an average center-to-center distance of 3.89 mm +/- 2.42 mm (0.69 pixels +/- 0.34 pixels). The ROI overlap ranged from 77% to 99%, with an average of 90% +/- 5.6%.

    CONCLUSIONS:

    Although the use of F-18 FDG CD shows great promise for the identification of tumors, it shares the same drawbacks as those associated with radiolabeled monoclonal antibody SPECT and ligand-based positron emission tomographic scans in that anatomic markers are limited. This study shows that image registration is feasible and may improve the clinical relevance of CD images.

  • 6.
    Alcala, Yvonne
    et al.
    New York Medical College .
    Olivecrona, Henrik
    Karolinska.
    Olivecrona, Lotta
    Karolinska.
    Noz, Marilyn E.
    New York University.
    Maguire Jr., Gerald Q.
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Mikroelektronik och Informationsteknik, IMIT.
    Zeleznik, Michael P.
    Sollerman, Christer
    Sahlgrenska University Hospital, Göteborg, Sweden.
    Qualifying CT for wrist arthroplasty: Extending techniques for total hip arthroplasty to total wrist arthroplasty2005Inngår i: Medical Imaging 2005: Image Processing, Pt 1-3 / [ed] Fitzpatrick, JM; Reinhardt, JM, SPIE - The International Sooceity for Optical Engineeering , 2005, Vol. 5747, s. 1155-1164Konferansepaper (Fagfellevurdert)
    Abstract [en]

    The purpose of this study was to extend previous work to detect migration of total wrist arthroplasty non-invasively, and with greater accuracy. Two human cadaverous arms, each with a cemented total wrist implant, were used in this study. In one of the arms, I mm tantalum balls were implanted, six in the carpal bones and five in the radius. Five CT scans of each arm were acquired, changing the position of the arm each time to mimic different positions patients might take on repeated examinations. Registration of CT volume data sets was performed using an extensively validated, 3D semi-automatic volume fusion tool in which co-homologous point pairs (landmarks) are chosen on each volume to be registered. Three sets of ten cases each were obtained by placing landmarks on 1) bone only (using only arm one), 2) tantalum implants only, and 3) bone and tantalum implants (both using only arm two). The accuracy of the match was assessed visually in 2D and 3D, and numerically by calculating the distance difference between the actual position of the transformed landmarks and their ideal position (i.e., the reference landmark positions). All cases were matched visually within one width of cortical bone and numerically within one half CT voxel (0.32 mm, p = 0.05). This method matched only the bone/arm and not the prosthetic component per se, thus making it possible to detect prosthetic movement and wear. This method was clinically used for one patient with pain. Loosening of the carpal prosthetic component was accurately detected and this was confirmed at surgery.

  • 7.
    Anderlind, Eva
    et al.
    KTH, Skolan för datavetenskap och kommunikation (CSC), Människa-datorinteraktion, MDI (stängd 20111231).
    Noz, Marilyn E.
    New York University, Department of Radiology.
    Sallnäs Pysander, Eva-Lotta
    KTH, Skolan för datavetenskap och kommunikation (CSC), Numerisk Analys och Datalogi, NADA.
    Lind, Bengt K.
    Karolinska Institute, Department of Medical Radiation Physics.
    Maguire, Gerald Q. Jr.
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Kommunikationssystem, CoS.
    Will haptic feedback speed up medical imaging? An application to radiation treatment planning2008Inngår i: Acta Oncologica, ISSN 0284-186X, E-ISSN 1651-226X, Vol. 47, nr 1, s. 32-37Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Haptic technology enables us to incorporate the sense of touch into computer applications, providing an additional input/output channel. The purpose of this study was to examine if haptic feedback can help physicians and other practitioners to interact with medical imaging and treatment planning systems. A haptic application for outlining target areas (a key task in radiation therapy treatment planning) was implemented and then evaluated via a controlled experiment with ten subjects. Even though the sample size was small, and the application only a prototype, results showed that haptic feedback can significantly increase (p0.05) the speed of outlining target volumes and organs at risk. No significant differences were found regarding precision or perceived usability. This promising result warrants further development of a full haptic application for this task. Improvements to the usability of the application as well as to the forces generated have been implemented and an experiment with more subjects is planned.

  • 8.
    Anderlind, Eva
    et al.
    KTH, Skolan för datavetenskap och kommunikation (CSC), Människa-datorinteraktion, MDI (stängd 20111231).
    Noz, Marilyn E.
    New York University, Department of Radiology.
    Sallnäs Pysander, Eva-Lotta
    KTH, Skolan för datavetenskap och kommunikation (CSC), Människa-datorinteraktion, MDI (stängd 20111231).
    Maguire Jr., Gerald Q.
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Kommunikationssystem, CoS.
    Lind, Bengt K.
    Karolinska Institute, Medical Radiation Physics.
    The value of haptic feedback in medical imaging and treatment planning2006Inngår i: Radiotherapy and Oncology, ISSN 0167-8140, E-ISSN 1879-0887, Vol. 81, s. 1277-Artikkel i tidsskrift (Fagfellevurdert)
  • 9.
    Barbette, Tom
    et al.
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Datavetenskap, Kommunikationssystem, CoS, Network Systems Laboratory (NS Lab).
    Katsikas, Georgios P.
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Datavetenskap, Kommunikationssystem, CoS, Network Systems Laboratory (NS Lab).
    Maguire Jr., Gerald Q.
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Datavetenskap, Kommunikationssystem, CoS, Radio Systems Laboratory (RS Lab).
    Kostic, Dejan
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Datavetenskap, Kommunikationssystem, CoS.
    RSS++: load and state-aware receive side scaling2019Inngår i: Proceedings of the 15th International Conference on emerging Networking EXperiments and Technologies / [ed] ACM, Orlando, FL, USA: Association for Computing Machinery (ACM), 2019Konferansepaper (Fagfellevurdert)
    Abstract [en]

    While the current literature typically focuses on load-balancing among multiple servers, in this paper, we demonstrate the importance of load-balancing within a single machine (potentially with hundreds of CPU cores). In this context, we propose a new load-balancing technique (RSS++) that dynamically modifies the receive side scaling (RSS) indirection table to spread the load across the CPU cores in a more optimal way. RSS++ incurs up to 14x lower 95th percentile tail latency and orders of magnitude fewer packet drops compared to RSS under high CPU utilization. RSS++ allows higher CPU utilization and dynamic scaling of the number of allocated CPU cores to accommodate the input load, while avoiding the typical 25% over-provisioning. RSS++ has been implemented for both (i) DPDK and (ii) the Linux kernel. Additionally, we implement a new state migration technique, which facilitates sharding and reduces contention between CPU cores accessing per-flow data. RSS++ keeps the flow-state by groups that can be migrated at once, leading to a 20% higher efficiency than a state of the art shared flow table.

    Fulltekst (pdf)
    RSSPP
  • 10.
    Barbette, Tom
    et al.
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Datavetenskap, Kommunikationssystem, CoS, Network Systems Laboratory (NS Lab).
    Tang, Chen
    KTH, Skolan för elektroteknik och datavetenskap (EECS).
    Yao, Haoran
    KTH, Skolan för elektroteknik och datavetenskap (EECS).
    Kostic, Dejan
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Datavetenskap, Kommunikationssystem, CoS, Network Systems Laboratory (NS Lab).
    Maguire Jr., Gerald Q.
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Datavetenskap, Kommunikationssystem, CoS.
    Papadimitratos, Panagiotis
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Datavetenskap, Kommunikationssystem, CoS.
    Chiesa, Marco
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Datavetenskap, Kommunikationssystem, CoS, Network Systems Laboratory (NS Lab).
    A High-Speed Load-Balancer Design with Guaranteed Per-Connection-Consistency2020Inngår i: 17th USENIX Symposium on Networked Systems Design and Implementation / [ed] USENIX Association, Santa Clara, CA, USA, 2020, s. 667-683Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Large service providers use load balancers to dispatch millions of incoming connections per second towards thousands of servers. There are two basic yet critical requirements for a load balancer: uniform load distribution of the incoming connections across the servers and per-connection-consistency (PCC), i.e., the ability to map packets belonging to the same connection to the same server even in the presence of changes in the number of active servers and load balancers. Yet, meeting both these requirements at the same time has been an elusive goal. Today's load balancers minimize PCC violations at the price of non-uniform load distribution.

    This paper presents Cheetah, a load balancer that supports uniform load distribution and PCC while being scalable, memory efficient, resilient to clogging attacks, and fast at processing packets. The Cheetah LB design guarantees PCC for any realizable server selection load balancing mechanism and can be deployed in both a stateless and stateful manner, depending on the operational needs. We implemented Cheetah on both a software and a Tofino-based hardware switch. Our evaluation shows that a stateless version of Cheetah guarantees PCC, has negligible packet processing overheads, and can support load balancing mechanisms that reduce the flow completion time by a factor of 2–3×.

    Fulltekst (pdf)
    cheetah.pdf
  • 11.
    Baxter, Brent S.
    et al.
    University of Utah.
    Hitchner, Lewis E.
    University of Utah.
    Maguire Jr., Gerald Q.
    Columbia University.
    A standard format for digital image exchange1982Bok (Annet vitenskapelig)
  • 12.
    Baxter, Brent S.
    et al.
    University of Utah.
    Hitchner, Lewis E.
    University of Utah.
    Maguire Jr., Gerald Q.
    University of Utah, Department of Computer Science.
    Characteristics of a Protocol for Exchanging Digital Image-information1982Inngår i: Proceedings of the Society of Photo-Optical Instrumentation Engineers, ISSN 0361-0748, Vol. 318, s. 273-277Artikkel i tidsskrift (Fagfellevurdert)
  • 13.
    Baxter, Brent S.
    et al.
    University of Utah.
    Zeleznik, Michael P.
    Maguire Jr., Gerald Q.
    Columbia University, Department of Computer Science.
    What Types of Standards would be useful in PACS Activities1983Inngår i: Proceedings of the Society of Photo-Optical Instrumentation Engineers, ISSN 0361-0748, Vol. 418, s. 146-150Artikkel i tidsskrift (Fagfellevurdert)
  • 14.
    Beadle, H.W.P.
    et al.
    Wollongong University.
    Harper, B.
    Maguire Jr., Gerald Q.
    KTH, Tidigare Institutioner, Teleinformatik.
    Judge, J.
    Location Aware Mobile Computing1997Inngår i: Proceedings of ICT '97, IEEE , 1997, s. 1319-1324Konferansepaper (Fagfellevurdert)
  • 15.
    Beadle, H.W.P.
    et al.
    Wollongong University.
    Maguire Jr., Gerald Q.
    KTH, Tidigare Institutioner, Teleinformatik.
    Smith, Mark T.
    Location Augmented Mobile Computing and Communication Systems1997Inngår i: Proc. Third Asia-Pacific Conference on Communications (APCC’97), 1997, s. 827-831Konferansepaper (Fagfellevurdert)
  • 16.
    Beadle, H.W.P.
    et al.
    Wollongong University.
    Maguire Jr., Gerald Q.
    KTH, Tidigare Institutioner, Teleinformatik.
    Smith, Mark T.
    Location Based Personal Mobile Computing and Communication1998Inngår i: Proceedings of 9th IEEE Workshop on Local and Metropolitan Area Networks, IEEE , 1998, s. 23-24Konferansepaper (Fagfellevurdert)
  • 17.
    Beadle, H.W.P.
    et al.
    Wollongong University.
    Maguire Jr., Gerald Q.
    KTH, Tidigare Institutioner, Teleinformatik.
    Smith, Mark T.
    Using location and environment awareness in mobile communications1997Inngår i: Proceedings of the International Conference on Information, Communications and Signal Processing, ICICS, IEEE , 1997, s. 1781-1785Konferansepaper (Fagfellevurdert)
    Abstract [en]

    We are investigating the use of badge based wearable computers to create highly mobile location and environment aware systems. When coupled to intelligent servers the badges provide an unparalleled platform for human centred information environments. This paper describes the architecture of the badge, its distributed computing environment, and presents initial results of application development trials conducted by a class of telecommunications students at KTH.

  • 18.
    Biema, Michael K. van
    et al.
    Columbia University.
    Maguire Jr., Gerald Q.
    Columbia University, Department of Computer Science.
    Lerner, Mark D.
    Columbia University.
    Stolfo, Salvatore J.
    Columbia University.
    The Design and Implementation of System Level Language for the DADO Parallel Machine1987Inngår i: Proceedings of the Twentieth Annual Hawaii International Conference on System Sciences 1987. Volume 3: Healthcare Systems, Special Topics, IEEE and ACM , 1987, s. 152-162Konferansepaper (Fagfellevurdert)
    Abstract [en]

    In this paper we describe necessary criteria for the design of parallel system level languages and their support environment. We base the criteria on our own experiences in building a system level language parallel PSL (Parallel Portable Standard Lisp) for the DADO machine developed at Columbia University. The DADO machine is a special purpose massively parallel binary tree structured architecture. We describe the process of language design and implementation on a 1023 node prototype machine. After generalizing what we have learned from this specific implementation to the generic task of building a system level language for a parallel machine, we conclude with a discussion of desirable characteristics such a language should have to allow the easy transition from a language with explicit parallelism to one where the parallelism is implicit.

  • 19.
    Biema, Michael K. van
    et al.
    Columbia University.
    Maguire Jr., Gerald Q.
    Columbia University, Department of Computer Science.
    Stolfo, Salvatore J.
    Columbia University.
    The constraint-based paradigm: integrating object-oriented and rule-based programming1990Inngår i: Proceedings of the Twenty-Third Annual Hawaii International Conference on System Sciences. Volume 1: Architecture Track, IEEE Computer Society, 1990, Vol. ii, s. 358-366Konferansepaper (Fagfellevurdert)
    Abstract [en]

    The authors introduce a novel formalism that combines the object-oriented and rule-based paradigms in an elegant and orthogonal way. The constraint-based model is a generalization of traditional object-oriented paradigms and is based on three orthogonal subparadigms. The first is constraint-based invocation, which is a generalization of the traditional invocation where dispatch is done based on the types of the arguments. In constraint-based invocation, dispatch is done based on constraints that are arbitrary user-defined predicates. The second subparadigm is instance inheritance, a dual to the concept of class inheritance in the sense that class inheritance structures classes and instance inheritance structures instances. The third is procedural attachments (also known as active values or access-oriented programming), where a function is called in a data-driven manner. The semantics of this concept are generalized to all objects in the constraint-based model. A central philosophical argument is that so-called multiparadigm languages should be developed not by combination of paradigms in a partially integrated system, but by their synergistic unification under a new, subsuming paradigm.

  • 20.
    Birnbaum, Bernard A.
    et al.
    New York University.
    Noz, Marilyn E.
    New York University.
    Chapnick, Jeffrey V.
    New York University.
    Sanger, Joseph J.
    New York University.
    Megibow, Alec J.
    New York University.
    Maguire Jr., Gerald Q.
    Columbia University, Department of Computer Science.
    Weinreb, Jeffrey C.
    New York University.
    Kaminer, Evan M.
    New York University.
    Kramer, Elissa L.
    New York University.
    Hepatic hemangiomas: diagnosis with fusion of MR, CT, and Tc-99m-labeled red blood cell SPECT images1991Inngår i: Radiology, ISSN 0033-8419, E-ISSN 1527-1315, Vol. 181, nr 2, s. 469-474Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A method of image analysis was developed for correlation of hemangiomas detected at computed tomography {(CT)} and/or magnetic resonance {(MR)} imaging with increased blood pool activity evident at single photon emission {CT} {(SPECT)} performed after labeling of red blood cells with technetium-99m. Image analysis was performed in 20 patients with 35 known hepatic hemangiomas. After section thickness and pixel sizes of the different studies were matched, intrinsic landmarks were chosen to identify anatomically corresponding locations. Regions of interest {(ROIs)} drawn on the {CT} and/or {MR} images were translated, rotated, and reprojected to match the areas of interest on the corresponding {SPECT} images by means of a two-dimensional polynomial-based warping algorithm. Analysis of {ROIs} on 30 {SPECT-MR} and 20 {SPECT-CT} pairs of registered images provided absolute confirmation that 34 suspected hemangiomas identified on {SPECT} images correlated exactly with lesions seen on {CT} and/or {MR} images. Accuracy of fusion was within an average of 1.5 pixels +/- 0.8 (+/- 1 standard deviation). The technique enabled diagnostic confirmation of hemangiomas as small as 1.0 cm and proved useful for evaluating lesions located adjacent to intrahepatic vessels.

  • 21.
    Birnbaum, Bernard A.
    et al.
    New York University.
    Noz, Marilyn E.
    New York University, Department of Radiology.
    Chapnick, Jeffrey V
    New York University.
    Sanger, Joseph J.
    New York University.
    Megibow, Alec J.
    New York University.
    Maguire Jr., Gerald Q.
    Columbia University, Computer Science.
    Weinreb, Jeffrey C.
    New York University.
    Kramer, Elissa L.
    New York University, Department of Radiology.
    Clinical Evaluation of Image Fusion Using MR Imaging, CT, and SPECT-RBC Images of Hepatic Hemangiomas1990Inngår i: Radiology, ISSN 0033-8419, E-ISSN 1527-1315, Vol. 177, s. P228-Artikkel i tidsskrift (Fagfellevurdert)
  • 22.
    Bogdanov, Kirill
    et al.
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Kommunikationssystem, CoS, Network Systems Laboratory (NS Lab).
    Peón-Quirós, Miguel
    Complutense University of Madrid.
    Maguire Jr., Gerald Q.
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Kommunikationssystem, CoS, Radio Systems Laboratory (RS Lab).
    Kostic, Dejan
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Kommunikationssystem, CoS, Network Systems Laboratory (NS Lab).
    The Nearest Replica Can Be Farther Than You Think2015Inngår i: Proceedings of the ACM Symposium on Cloud Computing 2015, Association for Computing Machinery (ACM), 2015, s. 16-29Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Modern distributed systems are geo-distributed for reasons of increased performance, reliability, and survivability. At the heart of many such systems, e.g., the widely used Cassandra and MongoDB data stores, is an algorithm for choosing a closest set of replicas to service a client request. Suboptimal replica choices due to dynamically changing network conditions result in reduced performance as a result of increased response latency. We present GeoPerf, a tool that tries to automate the process of systematically testing the performance of replica selection algorithms for geodistributed storage systems. Our key idea is to combine symbolic execution and lightweight modeling to generate a set of inputs that can expose weaknesses in replica selection. As part of our evaluation, we analyzed network round trip times between geographically distributed Amazon EC2 regions, and showed a significant number of daily changes in nearestK replica orders. We tested Cassandra and MongoDB using our tool, and found bugs in each of these systems. Finally, we use our collected Amazon EC2 latency traces to quantify the time lost due to these bugs. For example due to the bug in Cassandra, the median wasted time for 10% of all requests is above 50 ms.

    Fulltekst (pdf)
    fulltext
  • 23.
    Bogdanov, Kirill
    et al.
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Kommunikationssystem, CoS, Network Systems Laboratory (NS Lab).
    Peón-Quirós, Miguel
    Complutense University of Madrid.
    Maguire Jr., Gerald Q.
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Kommunikationssystem, CoS, Radio Systems Laboratory (RS Lab).
    Kostić, Dejan
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Kommunikationssystem, CoS, Network Systems Laboratory (NS Lab).
    Toward Automated Testing of Geo-Distributed Replica Selection Algorithms2015Inngår i: Proceedings of the 2015 ACM Conference on Special Interest Group on Data Communication, Association for Computing Machinery (ACM), 2015, s. 89-90Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Many geo-distributed systems rely on a replica selection algorithms to communicate with the closest set of replicas.  Unfortunately, the bursty nature of the Internet traffic and ever changing network conditions present a problem in identifying the best choices of replicas. Suboptimal replica choices result in increased response latency and reduced system performance. In this work we present GeoPerf, a tool that tries to automate testing of geo-distributed replica selection algorithms. We used GeoPerf to test Cassandra and MongoDB, two popular data stores, and found bugs in each of these systems.

  • 24.
    Bogdanov, Kirill
    et al.
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Kommunikationssystem, CoS, Network Systems Laboratory (NS Lab).
    Reda, Waleed
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Kommunikationssystem, CoS, Network Systems Laboratory (NS Lab). Université catholique de Louvain.
    Kostic, Dejan
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Kommunikationssystem, CoS, Network Systems Laboratory (NS Lab).
    Maguire Jr., Gerald Q.
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Kommunikationssystem, CoS.
    Canini, Marco
    KAUST.
    Kurma: Fast and Efficient Load Balancing for Geo-Distributed Storage Systems: Evaluation of Convergence and Scalability2018Rapport (Annet vitenskapelig)
    Abstract [en]

    This report provides an extended evaluation of Kurma, a practical implementation of a geo-distributed load balancer for backend storage systems. In this report we demonstrate the ability of distributed Kurma instances to accurately converge to the same solutions within 1% of the total datacenter’s capacity and the ability of Kurma to scale up to 8 datacenters using a single CPU core at each datacenter.

    Fulltekst (pdf)
    fulltext
  • 25.
    Bogdanov, Kirill
    et al.
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Kommunikationssystem, CoS.
    Reda, Waleed
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Kommunikationssystem, CoS.
    Maguire Jr., Gerald Q.
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Kommunikationssystem, CoS.
    Kostic, Dejan
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Kommunikationssystem, CoS.
    Canini, M.
    Fast and accurate load balancing for geo-distributed storage systems2018Inngår i: SoCC 2018 - Proceedings of the 2018 ACM Symposium on Cloud Computing, Association for Computing Machinery (ACM), 2018, s. 386-400Konferansepaper (Fagfellevurdert)
    Abstract [en]

    The increasing density of globally distributed datacenters reduces the network latency between neighboring datacenters and allows replicated services deployed across neighboring locations to share workload when necessary, without violating strict Service Level Objectives (SLOs). We present Kurma, a practical implementation of a fast and accurate load balancer for geo-distributed storage systems. At run-time, Kurma integrates network latency and service time distributions to accurately estimate the rate of SLO violations for requests redirected across geo-distributed datacenters. Using these estimates, Kurma solves a decentralized rate-based performance model enabling fast load balancing (in the order of seconds) while taming global SLO violations. We integrate Kurma with Cassandra, a popular storage system. Using real-world traces along with a geo-distributed deployment across Amazon EC2, we demonstrate Kurma’s ability to effectively share load among datacenters while reducing SLO violations by up to a factor of 3 in high load settings or reducing the cost of running the service by up to 17%.

    Fulltekst (pdf)
    fulltext
  • 26.
    Brodén, Cyrus
    et al.
    Department of Surgery and Cancer, Imperial College London, St Mary’s Hospital, London, UK2Karolinska Institutet, Department of Clinical Sciences, Danderyd Hospital, Division of Orthopaedics, Stockholm, Sweden.
    Giles, Joshua W.
    Department of Mechanical Engineering, University of Victoria, Victoria, BC, Canada4Mechatronics in Medicine Laboratory, Mechanical Engineering, Imperial College London, London, UK.
    Popat, Ravi
    Department of Bioengineering, Imperial College London, London, UK.
    Fetherston, Shirley
    Department of Radiology, St Mary’s Hospital, Imperial College Healthcare NHS Trust, London, UK.
    Olivecrona, Henrik
    Karolinska Institutet, Sweden.
    Sandberg, Olof
    Sectra, Linköping, Sweden.
    Maguire Jr., Gerald Q.
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Datavetenskap, Kommunikationssystem, CoS.
    Noz, Marilyn E.
    New York University, Department of Radiology.
    Sködenberg, Olof
    Karolinska Institutet, Department of Clinical Sciences, Danderyd Hospital, Division of Orthopaedics, Stockholm, Sweden.
    Emery, Roger
    Department of Surgery and Cancer, Imperial College London, St Mary’s Hospital, London, UK.
    Accuracy and precision of a CT method for assessing migration in shoulder arthroplasty: an experimental study2019Inngår i: Acta Radiologica, ISSN 0284-1851, E-ISSN 1600-0455Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Background: Radiostereometric analysis (RSA) is the gold standard to measure early implant migration which is a predictive factor for implant survival. Purpose: To validate an alternative computed tomography (CT) technique to measure implant migration in shoulder arthroplasty. Material and Methods: A cadaver proximal humerus and a scapula, which had tantalum beads incorporated within them, were prepared to accept a short-stemmed humeral component and a two-pegged glenoid component of a commercial total shoulder arthroplasty (TSA) system. A five degree of freedom micrometer and goniometer equipped rig was used to translate and rotate the implant components relative to the respective bone to predetermined positions. Double CT examinations were performed for each position and CT motion analysis software (CTMA) was used to assess these movements. The accuracy and precision of the software was estimated using the rig’s micrometers and goniometers as the gold standard. The technique’s effective dose was also assessed. Results: The accuracy was in the range of 0.07–0.23 mm in translation and 0.22–0.71° in rotation. The precision was in the range of 0.08–0.15 mm in translation and 0.23–0.54° in rotation. The mean effective dose for the CT scans was calculated to be 0.27 mSv. Conclusion: In this experimental setting, accuracy, precision, and effective dose of the CTMA technique were found to be comparable to that of RSA. Therefore, we believe clinical studies are warranted to determine if CTMA is a suitable alternative to traditional RSA for migration measurements in TSA.

  • 27.
    Brodén, Cyrus
    et al.
    Department of Molecular Medicine and Surgery, Karolinska Institutet.
    Olivecrona, Henrik
    Department of Molecular Medicine and Surgery, Karolinska Institutet.
    Maguire Jr., Gerald Q.
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Kommunikationssystem, CoS, Radio Systems Laboratory (RS Lab).
    Noz, Marilyn E.
    New York University, Department of Radiology.
    Zeleznik, Michael P.
    School of Computing, College of Engineering, University of Utah.
    Sköldenberg, Olof
    Department of Clinical Sciences, Danderyd Hospital, Karolinska Institutet.
    Accuracy and Precision of Three-Dimensional Low Dose CT Compared to Standard RSA in Acetabular Cups: An Experimental Study2016Inngår i: BioMed Research International, ISSN 2314-6133, E-ISSN 2314-6141, artikkel-id 5909741Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Background and Purpose. The gold standard for detection of implant wear and migration is currently radiostereometry (RSA). The purpose of this study is to compare a three-dimensional computed tomography technique (3D CT) to standard RSA as an alternative technique for measuring migration of acetabular cups in total hip arthroplasty.

    Materials and Methods. With tantalum beads, we marked one cemented and one uncemented cup and mounted these on a similarly marked pelvic model. A comparison was made between 3D CT and standard RSA for measuring migration. Twelve repeated stereoradiographs and CT scans with double examinations in each position and gradual migration of the implants were made. Precision and accuracy of the 3D CT were calculated.

    Results. The accuracy of the 3D CT ranged between 0.07 and 0.32 mm for translations and 0.21 and 0.82° for rotation. The precision ranged between 0.01 and 0.09 mm for translations and 0.06 and 0.29° for rotations, respectively. For standard RSA, the precision ranged between 0.04 and 0.09 mm for translations and 0.08 and 0.32° for rotations, respectively. There was no significant difference in precision between 3D CT and standard RSA. The effective radiation dose of the 3D CT method, comparable to RSA, was estimated to be 0.33 mSv.

    Interpretation. Low dose 3D CT is a comparable method to standard RSA in an experimental setting.

  • 28.
    Brown, Lisa G.
    et al.
    IBM Thomas J. Watson Research Center and Columbia University.
    Maguire Jr., Gerald Q.
    Columbia University, Department of Computer Science.
    Noz, Marilyn E.
    New York University.
    Landmark-based 3D fusion of SPECT and CT images1993Inngår i: Sensor fusion VI: 7-8 September 1993, Boston, Massachusetts / [ed] Paul S. Schenker, SPIE - International Society for Optical Engineering, 1993, Vol. 2059, s. 166-174Konferansepaper (Fagfellevurdert)
    Abstract [en]

    In this paper we present interactive visualization procedures for registration of SPECT and CT images based on landmarks. Because of the poor anatomic detail available in many SPECT images, registration of SPECT images with other modalities often requires the use of external markers. These markers may correspond to anatomic structures identifiable in the other modality image. In this work, we present a method to nonrigidly register SPECT and CT images based on automatic marker localization and interactive anatomic localization using 3D surface renderings of skin. The images are registered in 3D by fitting low order polynomials which are constrained to be near rigid. The method developed here exploits 3D information to attain greater accuracy and reduces the amount of time needed for expert interaction.

  • 29.
    Chandra, Ramesh
    et al.
    New York University.
    Lo, S.
    Noz, Marilyn E.
    New York University.
    Maguire Jr., Gerald Q.
    University of Utah, Department of Computer Science.
    Absorbed Fractions for Radionuclides Uniformly Distributed in the Myocardium1976Inngår i: Proceedings of the Radiopharmaceutical Dosimetry Symposium, Rockville, MD, USA: HEW Radiopharmaceutical Dosimetry Symposium , 1976, s. 199-207Konferansepaper (Fagfellevurdert)
  • 30.
    Chapnick, J. V.
    et al.
    New York University.
    Noz, Marilyn E.
    New York University.
    Maguire Jr., Gerald Q.
    Columbia University, Department of Computer Science.
    Kramer, Elissa L.
    New York University.
    Sanger, J. J.
    New York University.
    Birnbaum, B.A.
    New York University.
    Megibow, A.J.
    Techniques for multimodality image registration1993Inngår i: Bioengineering, Proceedings of the Northeast Conference, 1993, s. 221-222Konferansepaper (Fagfellevurdert)
    Abstract [en]

    The authors describe the development of techniques used for cross-modality correlation of medical images. To accomplish this goal, software routines were developed which automate and standardize the comparison of images within and between three-dimensional tomographic imaging modalities. Data from phantoms and clinical studies reflect the success of this technique.

  • 31.
    Chapnick, Jeffrey V
    et al.
    New York University.
    Noz, Marilyn E.
    New York University, Department of Radiology.
    Kramer, Elissa L.
    New York University, Department of Radiology.
    Sanger, Joseph J.
    New York University.
    Birnbaum, Bernard A.
    New York University.
    Maguire Jr., Gerald Q.
    Columbia University, Computer Science.
    Megibow, Alec J.
    New York University.
    Oratz, R.
    New York University, Department of Radiology.
    Weinreb, Jeffrey C.
    New York University.
    Martino, J.
    New York University.
    Structural, Functional Image Fusion in Cancer Patients1990Inngår i: Radiology, ISSN 0033-8419, E-ISSN 1527-1315, Vol. 177, s. P377-Artikkel i tidsskrift (Fagfellevurdert)
  • 32.
    Chapnick, Jeffrey V
    et al.
    New York University.
    Noz, Marilyn E.
    New York University, Department of Radiology.
    Maguire Jr., Gerald Q.
    Columbia University, Department of Computer Science.
    Sanger, Joseph J.
    New York University.
    Megibow, Alec J.
    New York University.
    Kramer, Elissa L.
    New York University, Department of Radiology.
    Oratz, R.
    New York University.
    Birnbaum, Bernard A.
    New York University.
    Martino, J.
    New York University.
    Fusion of Functional and Structural Images1990Inngår i: Radiology, ISSN 0033-8419, E-ISSN 1527-1315, Vol. 177, s. P223-Artikkel i tidsskrift (Fagfellevurdert)
  • 33.
    Chapnick, Jeffrey V
    et al.
    New York University.
    Noz, Marilyn E.
    New York University, Department of Radiology.
    Maguire Jr., Gerald Q.
    Columbia University, Department of Computer Science.
    Sanger, Joseph J.
    New York University.
    Megibow, Alec J.
    New York University.
    Kramer, Elissa L.
    New York University, Department of Radiology.
    Oratz, R.
    New York University, Department of Radiology.
    Birnbaum, Bernard A.
    New York University.
    Martino, J.
    New York University, Department of Radiology.
    Fusion of Functional Spect Images with Structural CT/MRI Images1991Inngår i: Journal of Nuclear Medicine, ISSN 0161-5505, E-ISSN 1535-5667, Vol. 32, s. 1135-Artikkel i tidsskrift (Fagfellevurdert)
  • 34.
    Crafoord, Joakim
    et al.
    Karolinska Hospital, Department of Radiology.
    Mahmoud, Faaiza
    New York University, Department of Radiology.
    Kramer, Elissa L.
    New York University, Department of Radiology.
    Maguire Jr., Gerald Q.
    KTH, Tidigare Institutioner, Mikroelektronik och informationsteknik, IMIT.
    Noz, Marilyn E.
    New York University, Department of Radiology.
    Zeleznik, Michael P.
    RAHD Oncology Products, St. Lois, MO, USA.
    Comparison of two landmark based image registration methods for use with a body atlas2000Inngår i: Physica medica (Testo stampato), ISSN 1120-1797, E-ISSN 1724-191X, Vol. 16, nr 2, s. 75-82Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    We describe preliminary work registering abdominal MRI images from three healthy male volunteers. Anatomically selected 3D homologous point pairs (landmarks), from which eigenvalues were generated to form the basis for a 3D non-affine polynomial transformation, were placed on axial slices alone and on axial, coronal and sagittal slices. Registration accuracy was judged visually by comparing superimposed 3D isosurfaces from the reference, untransformed, and transformed volume data and by comparing merged 2D slices projected fi om the transformed and reference volume data superimposed with 2D isolines. The squared sum of intensity differences between the transformed/untransformed and the reference volume was significant at the 0.05 (p >0.05) confidence level. The correlation coefficient improved by an average of 38% and the cross correlation between pixel values improved by an average of 22%. In each trial, the standard deviation of the landmarks after transformation was within one voxel and the standard error of the mean was not significantly different from zero at the 0.05 confidence level. Abdominal isosurface volume differences (between individuals) changed from an average of 14.5% before registration to 2.9% after registration. This experiment shows that it is possible to choose landmarks such that abdominal data from different subject volumes can be mapped to a common reference, and thus that it is possible to use this combined volume both to form an atlas and to warp abdominal data from an atlas to a patient volume.

  • 35.
    Dewyngaert, J. Keith
    et al.
    New York University.
    Noz, Marilyn E.
    New York University, Department of Radiology.
    Ellerin, B.
    New York University.
    Kramer, Elissa L.
    New York University, Department of Radiology.
    Maguire Jr., Gerald Q.
    KTH, Tidigare Institutioner, Mikroelektronik och informationsteknik, IMIT.
    Zeleznik, Michael P.
    RAHD Oncology Products, St. Louis, MO, USA.
    Procedure for unmasking localization information from ProstaScint scans for prostate radiation therapy treatment planning2004Inngår i: International Journal of Radiation Oncology, Biology, Physics, ISSN 0360-3016, E-ISSN 1879-355X, Vol. 60, nr 2, s. 654-662Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Purpose: To demonstrate a method to extract the meaningful biologic information from In-111-radiolabeled capromab pendetide (ProstaScint) SPECT scans for use in radiation therapy treatment planning by removing that component of the In-111 SPECT images associated with normal structures. Methods and Materials: We examined 20 of more than 80 patients who underwent simultaneous Tc-99m/In-111 SPECT scans, which were subsequently registered to the corresponding CT/MRI scans. A thresholding algorithm was used to identify Tc-99m uptake associated with blood vessels and CT electron density associated with bone marrow. Corresponding voxels were removed from the In-111 image set. Results: No single threshold value was found to be associated with the Tc-99m uptake that corresponded to the blood vessels. Intensity values were normalized to a global maximum and, as such, were dependent upon the quantity of Tc-99m pooled in the bladder. The reduced ProstaScint volume sets were segmented by use of a thresholding feature of the planning system and superimposed on the CT/MRI scans. Conclusions: ProstaScint images are now closer to becoming a biologically and therapeutically useful and accurate image set. After known sources of normal intensity are stripped away, the remaining areas that demonstrate uptake may be segmented and superimposed on the treatment-planning CT/MRI volume.

  • 36.
    Duchamp, Daniel J.
    et al.
    Columbia University, Department of Computer Science.
    Feiner, Steven K.
    Columbia University, Department of Computer Science.
    Kaiser, Gail E.
    Columbia University, Department of Computer Science.
    Maguire Jr., Gerald Q.
    Columbia University, Department of Computer Science.
    Integration of Knowledge Bases into an Environment of Portable Electronic Notebooks1990Rapport (Annet vitenskapelig)
  • 37.
    Duchamp, Daniel J.
    et al.
    Columbia University.
    Feiner, Steven K.
    Columbia University.
    Maguire Jr., Gerald Q.
    Columbia University, Department of Computer Science.
    Software technology for wireless mobile computing1991Inngår i: IEEE Network, ISSN 0890-8044, E-ISSN 1558-156X, Vol. 5, nr 6, s. 12-18Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Some of the possibilities and requirements for mobile computing on wireless local area networks (LANs) are discussed from the systems software viewpoint. The design of the Student Electronic Notebook (SEN) is sketched to provide a partial catalog of problems in building a real system for wireless mobile computing. This project was initiated to investigate the potential of wireless mobile computing to reshape education. Some of the key directions for research in software technology for wireless, mobile computing are examined. Some of the authors' experience with wireless LANs is related.

  • 38.
    Eisenstadter, Yoram
    et al.
    Columbia University.
    Maguire Jr., Gerald Q.
    Columbia University, Department of Computer Science.
    Exploiting Locality of Reference in MIMD Parallel Symbolic Computation1987Inngår i: Proceedings of the International Conference on Parallel Processing, IEEE, Pennsylvania State Univ. Press , 1987, s. 742-744Konferansepaper (Fagfellevurdert)
  • 39.
    Erdman, William A.
    et al.
    MIDDLESEX GEN UNIV HOSP,RUTGERS MED SCH,NEW BRUNSWICK,NJ 08901 .
    Maguire Jr., Gerald Q.
    Columbia University, Department of Computer Science.
    Noz, Marilyn E.
    New York University.
    Stahl, T. J.
    MIDDLESEX GEN UNIV HOSP,RUTGERS MED SCH,NEW BRUNSWICK,NJ 08901 .
    A Picture Archiving and Communication System - Modus Operandi for a Filmless Nuclear Medicine Department1986Inngår i: Administrative Radiology, ISSN 0738-6974, Vol. 5, nr 1, s. 34-38Artikkel i tidsskrift (Fagfellevurdert)
  • 40.
    Erdman, William A.
    et al.
    MIDDLESEX GEN UNIV HOSP,RUTGERS MED SCH,NEW BRUNSWICK,NJ 08901 .
    Stahl, T. J.
    MIDDLESEX GEN UNIV HOSP,RUTGERS MED SCH,NEW BRUNSWICK,NJ 08901 .
    Tokarz, R. J.
    MIDDLESEX GEN UNIV HOSP,RUTGERS MED SCH,NEW BRUNSWICK,NJ 08901 .
    Maguire Jr., Gerald Q.
    Columbia University, Department of Computer Science.
    Noz, Marilyn E.
    New York University.
    Development of a Digital Nuclear-Medicine System1983Inngår i: Proceedings of the Society of Photo-Optical Instrumentation Engineers, ISSN 0361-0748, Vol. 418, s. 100-102Artikkel i tidsskrift (Fagfellevurdert)
  • 41.
    Ericson, Anne
    et al.
    Karolinska Institute, Department of Molecular Medicine and Surgery, Section of Orthopaedics and Sports Medicine.
    Arndt, Anton
    Karolinska Institut, Department of Clinical Science, Intervention and Technology, Section of Orthopaedics.
    Stark, Andreas
    Karolinska Institute, Department of Molecular Medicine and Surgery.
    Noz, Marilyn E.
    New York University, Department of Radiology.
    Maguire Jr., Gerald Q.
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Kommunikationssystem, CoS.
    Zeleznik, Michael P.
    Saya Systems Inc., Salt Lake City, UT, USA.
    Olivecrona, Henrik
    Karolinska Institute, Department of Molecular Medicine and Surgery.
    Fusion of radio stereometric analysis data into computed tomography space: Application to the elbow joint2007Inngår i: Journal of Biomechanics, ISSN 0021-9290, E-ISSN 1873-2380, Vol. 40, nr 2, s. 296-304Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Improvement of joint prostheses is dependent upon information concerning the biomechanical properties of the joint. Radiostereometric analysis (RSA) and electromagnetic techniques have been applied in previous cadaver and in vivo studies on the elbow joint to provide valuable information concerning joint motion axes. However, such information is limited to mathematically calculated positions of the axes according to an orthogonal coordinate system and is difficult to relate to individual skeletal anatomy. The aim of this study was to evaluate the in vivo application of a new fusion method to provide three-dimensional (31)) visualization of flexion axes according to bony landmarks. In vivo RSA data of the elbow joint's flexion axes was combined with data obtained by 3D computed tomography (CT). Results were obtained from five healthy subjects after one was excluded due to an instable RSA marker. The median error between imported and transformed RSA marker coordinates and those obtained in the CT volume was 0.22mm. Median maximal rotation error after transformation of the rigid RSA body to the CT volume was 0.003 degrees. Points of interception with a plane calculated in the RSA orthogonal coordinate system were imported into the CT volume, facilitating the 3D visualization of the flexion axes. This study demonstrates a successful fusion of RSA and CT data, without significant loss of RSA accuracy. The method could be used for relating individual motion axes to a 3D representation of relevant joint anatomy, thus providing important information for clinical applications such as the development of joint prostheses.

  • 42.
    Ericson, Anne
    et al.
    Karolinska Institute, Department of Molecular Medicine and Surgery, Section of Orthopaedics and Sports Medicine.
    Olivecrona, Henrik
    Karolinska Institute, Department of Molecular Medicine and Surgery.
    Stark, Andreas
    Karolinska Institute, Department of Molecular Medicine and Surgery.
    Noz, Marilyn E.
    New York University, Department of Radiology.
    Maguire Jr., Gerald Q.
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Kommunikationssystem, CoS.
    Zeleznik, Michael P.
    Saya Systems Inc., Salt Lake City, UT, USA.
    Arndt, Anton
    Karolinska Institut, Department of Clinical Science, Intervention and Technology, Section of Orthopaedics.
    Computed tomography analysis of radiostereometric data to determine flexion axes after total joint replacement: Application to the elbow joint2010Inngår i: Journal of Biomechanics, ISSN 0021-9290, E-ISSN 1873-2380, Vol. 43, nr 10, s. 1947-1952Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Kinematic analysis for in vivo assessment of elbow endoprostheses requires knowledge of the exact positions of motion axes relative to bony landmarks or the prosthesis. A prosthesis-based reference system is required for comparison between individuals and studies. The primary aim of this study was to further develop an earlier described algorithm for fusion of radiostereometric analysis (RSA) data and data obtained in 3D computed tomography (CT) for application to the elbow after total joint replacement. The secondary aim was to propose a method for marking of prostheses in 3D CT, enabling definition of a prosthesis-based reference system. Six patients with elbow endoprostheses were investigated. The fusion of data made it possible to visualize the motion axes in relation to the prostheses in the 3D CT volume. The differences between two repeated positioning repetitions of the longitudinal prosthesis axis were less than 0.6 degrees in the frontal and sagittal planes. Corresponding values for the transverse axis were less than 0.6 degrees in the frontal and less than 1.4 degrees (in four out of six less than 0.6 degrees) in the horizontal plane. This study shows that by fusion of CT and RSA data it is possible to determine the accurate position of the flexion axes of the elbow joint after total joint replacement in vivo. The proposed method for implant marking and registration of reference axes enables comparison of prosthesis function between patients and studies.

  • 43.
    Eriksson, Thomas
    et al.
    Department of Radiology, Centre for Medical Imaging, Uppsala University Hospital, Uppsala, Sweden.
    Maguire Jr., Gerald Q.
    KTH, Skolan för elektroteknik och datavetenskap (EECS).
    Noz, Marilyn E.
    New York University, Department of Radiology.
    Zeleznik, Michael P.
    University of Utah.
    Olivecrona, Henrik
    Karolinska Institutet, Sweden.
    Shalabi, Adel
    Department of Radiology, Centre for Medical Imaging, Uppsala University Hospital, Uppsala, Sweden.
    Hänni, Mari
    Department of Radiology, Centre for Medical Imaging, Uppsala University Hospital, Uppsala, Sweden.
    Are low-dose CT scans a satisfactory substitute for stereoradiographs for migration studies? A preclinical test of low-dose CT scanning protocols and their application in a pilot patient.2019Inngår i: Acta Radiologica, ISSN 0284-1851, E-ISSN 1600-0455, artikkel-id 284185119844166Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    BACKGROUND: Computed tomography (CT) has the potential to acquire the data needed for migration studies of orthopedic joint implants of patients who have had tantalum beads implanted at the time of joint replacement surgery. This can be accomplished with the same precision as radiostereometric analysis (RSA). Switching to CT would increase availability without the need for the specific facilities required for RSA. However, higher effective dose is a concern.

    PURPOSE: To investigate if migration measurements can be done with CT with an accuracy and effective dose comparable to that of conventional RSA.

    MATERIAL AND METHODS: Fourteen scanning protocols were tested in a hip phantom that incorporated tantalum beads and an uncemented femoral stem. The protocols were graded for clinical practice according to the three parameters of image quality, effective dose, and robustness of numerical data. After grading, the two protocols that graded best overall were applied to a pilot patient.

    RESULTS: All protocols produced scans in which the numerical data were sufficient for a migration analysis at least as precise as would be expected using RSA. A protocol with an effective dose of 0.70 mSv was shown to be applicable in a pilot patient.

    CONCLUSION: Low-dose CT scans with an effective dose comparable to a set of routine plain radiographs can be used for precise migration measurements.

  • 44.
    Escudero-Pascual, Alberto
    et al.
    KTH, Tidigare Institutioner, Mikroelektronik och informationsteknik, IMIT.
    Maguire Jr., Gerald Q.
    KTH, Tidigare Institutioner, Wireless at KTH. KTH, Tidigare Institutioner, Mikroelektronik och informationsteknik, IMIT.
    Role(s) of a proxy in location based services2002Inngår i: 13TH IEEE INTERNATIONAL SYMPOSIUM ON PERSONAL, INDOOR AND MOBILE RADIO COMMUNICATIONS, VOL 1-5, PROCEEDINGS: SAILING THE WAVES OF THE WIRELESS OCEANS, IEEE , 2002, s. 1252-1256Konferansepaper (Fagfellevurdert)
    Abstract [en]

    We examine a number of roles that a proxy server can play in location based services and how it can be used to provide protection of personal identifiable information. Location data, service requests, and privacy policies are encoded in XML by the mobile terminal and forwarded to a proxy server placed between the mobile terminal and the location based service(s). By a suitable architecture in the mobile terminal and in the proxy, we can hide the mobile device's network location, hide the identity of its user, and, in some cases, provide misleading physical location(s). We have applied our privacy model to location information obtained from a GPS receiver. The GPS-based method was chosen as being the only available method where the positioning calculation function (PCF) is fully under the user's control, since the position is calculated within the mobile terminal; other technologies rely on the network infrastructure, and hence some or all of the position data is outside the user's control. A proof of concept was implemented using Fastrax's iTrax02 small, ultra-low power consumption GPS receiver. We illustrate a number of different functions which can be provided by examining some scenarios.

  • 45.
    Farrell, Edward J.
    et al.
    IBM Research.
    Gorniak, Richard J.
    New York University.
    Kramer, Elissa L.
    New York University.
    Noz, Marilyn E.
    New York University.
    Maguire Jr., Gerald Q.
    KTH, Tidigare Institutioner, Teleinformatik.
    Reddy, David P.
    Graphical 3D medical image registration and quantification1997Inngår i: Journal of medical systems, ISSN 0148-5598, E-ISSN 1573-689X, Vol. 21, nr 3, s. 155-172Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    We present a graphical three-dimensional method that facilitates image registration and fusion, and provides quantitative geometric and volume information. In particular it enhances the use of functional (radiopharmaceutical) imaging {(SPECT}, {PET)} which, though a powerful clinical tool, has the disadvantage of low spatial resolution and ill-defined boundaries. Registration between functional images and structural images {(MRI}, {CT)} can augment the anatomical context of these functional images.

  • 46.
    Farrell, Edward J.
    et al.
    IBM Thomas J. Watson Research Center.
    Kramer, Elissa L.
    New York University.
    Noz, Marilyn E.
    New York University.
    Maguire Jr., Gerald Q.
    KTH, Tidigare Institutioner, Teleinformatik.
    Quantitative 3D visualization in nuclear medicine1995Inngår i: Proceedings of the SPIE Medical Imaging 1995, SPIE - International Society for Optical Engineering, 1995, Vol. 2431, s. 54-64Konferansepaper (Fagfellevurdert)
    Abstract [en]

    SPECT is a powerful clinical tool. However, the low spatial resolution and ill-defined boundaries associated with SPECT require special consideration in visualization. Quantitative geometric and magnitude information are areas of particular usefulness in evaluating disease states. In this paper, we describe a set of practical 3D visualization tools to display and analyze SPECT data, and present interactive methods to measure (1) the relative position, size and shape of regions of interest and (2) the magnitude and distribution of radioactive count information. Interactive pick tools allow users to extract values at selected points, distance between points, or value profiles along selected line segments. In the three-dimensional reconstruction, transparent and opaque isosurfaces are formed simultaneously at specified activity levels, and the volume enclosed by the opaque surface is displayed. The utility of these tools is demonstrated with two types of patient studies: those using tumor-avid agents to identify active tumor in the chest and abdomen, and those used for evaluating the volume of perfused myocardium.

  • 47.
    Farshin, Alireza
    et al.
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Kommunikationssystem, CoS, Network Systems Laboratory (NS Lab).
    Roozbeh, Amir
    Ericsson Research.
    Maguire Jr., Gerald Q.
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Kommunikationssystem, CoS.
    Kostic, Dejan
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Kommunikationssystem, CoS.
    Make the Most out of Last Level Cache in Intel Processors2019Inngår i: Proceedings of the Fourteenth EuroSys Conference (EuroSys'19), Dresden, Germany, 25-28 March 2019., ACM Digital Library, 2019Konferansepaper (Fagfellevurdert)
    Abstract [en]

    In modern (Intel) processors, Last Level Cache (LLC) is divided into multiple slices and an undocumented hashing algorithm (aka Complex Addressing) maps different parts of memory address space among these slices to increase the effective memory bandwidth. After a careful study of Intel’s Complex Addressing, we introduce a slice-aware memory management scheme, wherein frequently used data can be accessed faster via the LLC. Using our proposed scheme, we show that a key-value store can potentially improve its average performance ∼12.2% and ∼11.4% for 100% & 95% GET workloads, respectively. Furthermore, we propose CacheDirector, a network I/O solution which extends Direct Data I/O (DDIO) and places the packet’s header in the slice of the LLC that is closest to the relevant processing core. We implemented CacheDirector as an extension to DPDK and evaluated our proposed solution for latency-critical applications in Network Function Virtualization (NFV) systems. Evaluation results show that CacheDirector makes packet processing faster by reducing tail latencies (90-99th percentiles) by up to 119 µs (∼21.5%) for optimized NFV service chains that are running at 100 Gbps. Finally, we analyze the effectiveness of slice-aware memory management to realize cache isolation

    Fulltekst (pdf)
    fulltext
  • 48.
    Farshin, Alireza
    et al.
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Datavetenskap, Kommunikationssystem, CoS, Network Systems Laboratory (NS Lab).
    Roozbeh, Amir
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Datavetenskap, Kommunikationssystem, CoS, Network Systems Laboratory (NS Lab). Ericsson Research.
    Maguire Jr., Gerald Q.
    KTH, Tidigare Institutioner (före 2005), Mikroelektronik och informationsteknik, IMIT. KTH, Tidigare Institutioner (före 2005), Teleinformatik. KTH, Tidigare Institutioner (före 2005), Wireless at KTH. KTH, Skolan för elektroteknik och datavetenskap (EECS), Datavetenskap, Kommunikationssystem, CoS.
    Kostic, Dejan
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Datavetenskap, Kommunikationssystem, CoS, Network Systems Laboratory (NS Lab).
    Make the Most out of Last Level Cache in Intel Processors2019Inngår i: Proceedings of the Fourteenth EuroSys Conference (EuroSys'19), Dresden, Germany, 25-28 March 2019., 2019Konferansepaper (Fagfellevurdert)
    Fulltekst (pdf)
    fulltext
  • 49.
    Farshin, Alireza
    et al.
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Datavetenskap, Kommunikationssystem, CoS, Network Systems Laboratory (NS Lab).
    Roozbeh, Amir
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Datavetenskap, Kommunikationssystem, CoS, Network Systems Laboratory (NS Lab). Ericsson Research.
    Maguire Jr., Gerald Q.
    KTH, Tidigare Institutioner (före 2005), Mikroelektronik och informationsteknik, IMIT. KTH, Tidigare Institutioner (före 2005), Teleinformatik. KTH, Tidigare Institutioner (före 2005), Wireless at KTH. KTH, Skolan för elektroteknik och datavetenskap (EECS), Datavetenskap, Kommunikationssystem, CoS.
    Kostic, Dejan
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Datavetenskap, Kommunikationssystem, CoS, Network Systems Laboratory (NS Lab).
    Optimizing Intel Data Direct I/O Technology for Multi-hundred-gigabit Networks2020Inngår i: Proceedings of the Fifteenth EuroSys Conference (EuroSys'20), Heraklion, Crete, Greece, April 27-30, 2020., 2020Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Digitalization across society is expected to produce a massive amount of data, leading to the introduction of faster network interconnects. In addition, many Internet services require high throughput and low latency. However, having only faster links does not guarantee throughput or low latency. Therefore, it is essential to perform holistic system optimization to fully take advantage of the faster links to provide high-performance services. Intel Data Direct I/O (DDIO) is a recent technology that was introduced to facilitate the deployment of high-performance services based on fast interconnects. We evaluated the effectiveness of DDIO for multi-hundred-gigabit networks. This paper briefly discusses our findings on DDIO, which show the necessity of optimizing/adapting it to address the challenges of multi-hundred-gigabit-per-second links.

    Fulltekst (pdf)
    Extended Abstract
    Download (pdf)
    Poster
    Download (mp4)
    1-min Video Teaser
    Download (pdf)
    1-slide Teaser
  • 50.
    Försth, Peter
    et al.
    Department of Orthopedics, Institution of Surgical Sciences, Uppsala University Hospital.
    Svedmark, Per
    Karolinska Institutet at Karolinska University Hospital Solna.
    Noz, Marilyn E.
    New York University, Department of Radiology.
    Maguire Jr., Gerald Q.
    KTH, Skolan för informations- och kommunikationsteknik (ICT). Department of Orthopedics, Institution of Surgical Science, Uppsala University Hospital, Uppsala.
    Zeleznik, Michael P.
    University of Utah.
    Sandén, Bengt
    Department of Orthopedics, Institution of Surgical Science, Uppsala University Hospital, Uppsala.
    Motion Analysis in Lumbar Spinal Stenosis With Degenerative Spondylolisthesis: A Feasibility Study of the 3DCT Technique Comparing Laminectomy Versus Bilateral Laminotomy.2018Inngår i: Clinical spine surgery, ISSN 2380-0186, Vol. 31, nr 8, s. E397-E402Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Study Design: This was a randomized radiologic biomechanical pilot study in vivo. Objective: The objectives of this study was to evaluate if 3-dimensional computed tomography is a feasible tool in motion analyses of the lumbar spine and to study if preservation of segmental midline structures offers less postoperative instability compared with central decompression in patients with lumbar spinal stenosis with degenerative spondylolisthesis. Summary of Background Data: The role of segmental instability after decompression is controversial. Validated techniques for biomechanical evaluation of segmental motion in human live subjects are lacking. Methods: In total, 23 patients (mean age, 68 y) with typical symptoms and magnetic resonance imaging findings of spinal stenosis with degenerative spondylolisthesis (>3 mm) in 1 or 2 adjacent lumbar levels from L3 to L5 were included. They were randomized to either laminectomy (LE) or bilateral laminotomy (LT) (preservation of the midline structures). Documentation of segmental motion was made preoperatively and 6 months postoperatively with CT in provoked flexion and extension. Analyses of movements were performed with validated software. The accuracy for this method is 0.6 mm in translation and 1 degree in rotation. Patient-reported outcome measures were collected from the Swespine register preoperatively and 2-year postoperatively. Results: The mean preoperative values for 3D rotation and translation were 6.2 degrees and 1.8 mm. The mean increase in 3D rotation 6 months after surgery was 0.25 degrees after LT and 0.7 degrees after LE (P=0.79) while the mean increase in 3D translation was 0.15 mm after LT and 1.1 mm after LE (P=0.42). Both surgeries demonstrated significant improvement in patient-reported outcome measures 2 years postoperatively. Conclusions: The 3D computed tomography technique proved to be a feasible tool in the evaluation of segmental motion in this group of older patients. There was negligible increase in segmental motion after decompressive surgery. LE with removal of the midline structures did not create a greater instability compared with when these structures were preserved.

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