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TH-AB-209-12: Tissue Equivalent Phantom with Excised Human Tissue for Assessing Clinical Capabilities of Coherent Scatter Imaging Applications

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Medical Physics 2016年第6PART44期43卷 3866-3866页

作者： K Albanese R Morris J Spencer J Greenberg A Kapadia Medical Physics Graduate Program Duke University Durham NC Dept. of Electrical and Computer Engineering Duke University Durham NC Carl E Ravin Advanced Imaging Laboratories Durham NC

Purpose: Previously we reported the development of anthropomorphic tissue-equivalent scatter phantoms of the human breast. Here we present the first results from the scatter imaging of the tissue equivalent breast phantoms for breast cancer diagnosis. Methods: A breast phantom was designed to assess the capability of coded aperture coherent x-ray scatter imaging to classify different types of breast tissue (adipose, fibroglandular, tumor). The phantom geometry was obtained from a prone breast geometry scanned on a dedicated breast CT system. The phantom was 3D printed using the segmented DICOM breast CT data. The 3D breast phantom was filled with lard (as a surrogate for adipose tissue) and scanned in different geometries alongside excised human breast tissues (obtained from lumpectomy and mastectomy procedures). The raw data were reconstructed using a model-based reconstruction algorithm and yielded the location and form factor (i.e., momentum transfer (q) spectrum) of the materials that were imaged. The measured material form factors were then compared to the ground truth measurements acquired by x-ray diffraction (XRD) imaging. Results: Our scatter imaging system was able to define the location and composition of the various materials and tissues within the phantom. Cancerous breast tissue was detected and classified through automated spectral matching and an 86% correlation threshold. The total scan time for the sample was approximately 10 minutes and approaches workflow times for clinical use in intra-operative or other diagnostic tasks. Conclusion: This work demonstrates the first results from an anthropomorphic tissue equivalent scatter phantom to characterize a coherent scatter imaging system. The functionality of the system shows promise in applications such as intra-operative margin detection or virtual biopsy in the diagnosis of breast cancer. Future work includes using additional patient-derived tissues (e.g., human fat), and modeling additional organs (

关键词： X-ray scattering Medical X-ray imaging Cancer Coherence imaging Medical image reconstruction Tissue diagnostics Coded aperture imaging Computed tomography

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Are folksonomies shared conceptualizations?

Are folksonomies shared conceptualizations?

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International Conference on computer Supported Cooperative Work in Design

作者： Josiane M. Pinheiro Cesar A. Tacla Emerson Cabrera Paraiso Graduate Prog. in Electrical and Computer Engineering Federal Technological University of Parana Curitiba-Pr Brazil Graduate Program in Informatics Pontificia Universidade Catolica do Parana Curitiba-Pr Brazil

This article presents a method to assess whether folksonomies are useful shared conceptualizations for conceptual modeling. A method based on the tripartite model (actors, concepts and instances) induces from social applications a folksonomy related to a domain of knowledge. The hypothesis of this paper is that if folksonomies are shared conceptualizations, then using them in conceptual modeling should reduce the number of divergences between actors when they elicit terms to be part of a model (a concept map in this article). A controlled experiment of conceptual modeling was performed with experimental groups who received tags inducted from data of categorizations from Delicious and control groups who received terms extracted from Web pages categorized on Delicious. The results show that the experimental groups obtained less divergences (on average) in elicitation of terms when compared to control groups.

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Performance of Cognitive Spectrum Sensing Based on Energy Detector in Fading Channels

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Procedia computer Science 2015年 65卷 140-147页

作者： Fabrício B.S. de Carvalho Waslon T.A. Lopes Marcelo S. Alencar Post-Graduate Program in Electrical Engineering – PPgEE – COPELE Federal University of Campina Grande Department of Electrical Engineering Campina Grande-PB 58429-900 Brazil Federal University of Paraíba Department of Electrical Engineering João Pessoa-PB 58051-970 PO BOX 5115 Brazil Institute of Advanced Studies in Communications (Iecom) Campina Grande-PB 58109-970 Brazil

Spectrum scarcity and the inefficient use of the electromagnetic spectrum motivated the development of Cognitive Radio (CR), which aims to extend the spectral efficiency, with opportunistic access to the available frequency bands. Energy Detection (ED) is the most adopted spectrum sensing technique for cognitive radio applications due to its simplicity. However, fading effects are usually simplified or discarded when evaluating the energy detector performance in spectrum sensing. This paper presents the performance evaluation of cognitive spectrum sensing, based on energy detector, for fading channels. The objective is to analyze how the use of various fading models affect the spectral detection in cognitive networks. Rayleigh, Rice, Nakagami-m and Lognormal fading channels are considered, and the results favor the use of ED when the channel is subject to Lognormal fading.

关键词： Cognitive Radio Spectrum Sensing Energy Detector Fading Channels

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Stochastic unit commitment in a distribution system with photovoltaic power: Empirical assessment

Stochastic unit commitment in a distribution system with pho...

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International Conference on Environment and electrical engineering (EEEIC)

作者： Thaís F. Araújo Wadaed Uturbey Luis G. Monteiro Le Xie Graduate Program in Electrical Engineering Federal University of Minas Gerais Belo Horizonte MG Brazil Electrical Engineering Department Federal University of Minas Gerais Belo Horizonte MG Brazil Department of Electrical and Computer Engineering Texas A&M University College Station Texas

ISBN: (纸本)9781479979943

This paper proposes an economic dispatch strategy to accommodate photovoltaic (PV) generation, using the solar radiation historical data. The stochastic scenario based economic dispatch approach is formulated in the context of a power system with photovoltaic generators. The stochastic nature of PV power is represented through scenarios. The strategy proposed addresses the improvement of system ability to maintain the power balance while minimizing the management costs of power system. The benefits of this approach are illustrated using a modified version of the IEEE 30-bus test system. The results obtained show that the proposed model is appropriated to accommodate the estimation error of PV generation, while providing economic benefits.

关键词： Generators Stochastic processes Production Solar radiation Power systems Predictive models Economics

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Hybrid multilevel inverter system for Open-End Winding (OEW) induction motor drive based on Double-Star Chopper-Cells (DSCC) converter

Hybrid multilevel inverter system for Open-End Winding (OEW)...

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Annual IEEE Conference on Applied Power Electronics Conference and Exposition (APEC)

作者： Italo Roger F. M. P. da Silva Cursino B. Jacobina Alexandre C. Oliveira Gregory A. de Almeida Carlos Maurício B. de R. Corrîa Post-graduate Program in Electrical Engineering PPgEE/COPELE Department of Electrical Engineering (DEE) Federal University of Campina Grande (UFCG) Campina Grande PB Brazil Department of Control and Industrial Process Federal Institute of Alagoas (IFAL) Palmeira dos Indios AL Brazil

ISBN: (纸本)9781479967360

This paper proposes a hybrid multilevel topology for Open-End stator Winding (OEW) induction motor drive based on Modular Multilevel Cascade Inverter (MMCI) with Double-Star Chopper-Cells (DSCC) and 2-Level Voltage Source Inverter (2L-VSI). An efficient Voltage Reference Technique is proposed to generate the pole voltages of both inverters. As a result, the DSCC inverter is commanded in high-switching frequency, while the 2L-VSI operates at the fundamental frequency. A voltage-balancing control of the floating DC capacitors of the DSCC is presented to ensure the energy balance. At last, to investigate the proposed system and control strategy, experimental results are presented.

关键词： Voltage control Inverters Induction motors Topology Capacitors Inductors Logic gates

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Smartphone spectrophotometer for point-of-care diagnostics in low-resource settings

Smartphone spectrophotometer for point-of-care diagnostics i...

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IEEE Region 10 Humanitarian Technology Conference (R10-HTC)

作者： Supriti Gupta Hwee Choo Liaw Prahlad Vadakkepat C. Frank Starmer Engineering Design and Innovation Centre National University of Singapore Dept. Electrical and Computer Engineering National University of Singapore Cardiovascular and Metabolic Disorders Program Duke NUS Graduate Medical School

Colorimetry based point-of-care diagnostics provide an inexpensive technique for healthcare and environmental monitoring during disaster relief operations. Conventional equipments for measuring colorimetric assays are bulky and expensive, making them unsuitable for usage in low-resource settings. This paper proposes a novel approach for taking colorimetric measurements using a miniaturized spectrophotometer prototype attached to a smartphone. The proposed frugal design is portable, easy-to-use and costs less than US$15. High dynamic range imaging is used to process the spectrums captured by smartphone camera. The proposed algorithm supports JPEG image format, allowing the prototype to be used with a wide variety of smartphone models. In the experimental study, spectrums of color dye and milk samples are imaged. Spectrums obtained are found to be well correlated with the sample color and concentration. By providing accurate and fast measurements, smartphone spectrophotometry enables effective application of colorimetric diagnostic techniques in low-resource settings.

关键词： Cameras Prototypes Dairy products Heuristic algorithms Image color analysis Dynamic range

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Analysis of the resonant behavior of FSS using matryoshka geometry

Analysis of the resonant behavior of FSS using matryoshka ge...

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SBMO/IEEE MTT-S International Conference on Microwave and Optoelectronics (IMOC)

作者： Alfrêdo Gomes Neto Jefferson C. e Silva Joabson Nogueira de Carvalho Josiel Do Nascimento Cruz Hillner De Paiva Almeida Ferreira Group of Telecom. and Applied Electromagnetism Federal Inst. of Educ. Science and Technology of Paraiba Joao Pessoa PB Brazil Post-Graduate Program in Electrical Engineering Federal University of Campina Grande Brazi Brazil Group of Telecom. and Applied Electromagnetism Federal Inst. of Educ. Science and Technology of Paraíba Brazil Post-Graduate Program in Electrical Engineering Universidade Federal de Campina Grande Campina Grande PB BR

ISBN: (纸本)9781467394932

In this paper the resonant behavior of frequency selective surfaces, FSS, using matryoshka geometry is analyzed considering polarizations x and y. The basics of the FSS using matryoshka geometry are described for usual and open cases, including an expression to estimate the first resonant frequency. Initially, the FSS with two concentric square rings is considered and its resonant behavior analyzed. Then, the resonant behavior of FSS with two rings matryoshka geometry is examined. The analysis is based on the electric current distribution obtained using the commercial software ANSYS-Designer. With a better understanding of the resonance nature in matryoshka geometry the design parameters can be better adjusted and desired frequency responses properly achieved.

关键词： Frequency selective surfaces Geometry Resonant frequency Current Frequency response Europe

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Message

Message

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Conference on Advances in Signal Processing (CASP)

作者： Shri Promoad Gorhe Pradeep K. Sinha Madhuri A. Joshi M. B. Khambete Prachi Mukherji James L Garrison Pramod Kale Hemant A. Patil Aditya Abhyankar Arnab Das Maharshi Karve Stree Shikshan Samstha New Raipur University FIET (U.K.) FIE (I) FIETE (I) IET Pune Local Network College of Engineering Pune CCEW General Chair CASP-2016 (E&TC) CCEW Co Chair CASP-2016 Aeronautics and Astronautics Electrical and Computer Engineering (by courtesy) Ecological Sciences & Engineering Interdisciplinary Graduate Program Purdue University USA ICIT Pvt. Ltd. Pune Former Director ISRO DA-IICT Gandhinagar Gujarat State Faculty of Technology University of Pune Department of Technology University of Pune Acoustic Research Lab of the Tropical Marine Science Institute at the National University of Singapore Retd. Electrical Officer Indian Navy (1994 - 2015) Adjunct Faculty at IIT Delhi and DIAT Pune

Presents the introductory welcome message from the conference proceedings. May include the conference officers' congratulations to all involved with the conference event and publication of the proceedings record.

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Vibration Measurement of Induction Motor Under Dynamic Eccentricity Using Optical Fiber Bragg Grating Sensors

Vibration Measurement of Induction Motor Under Dynamic Eccen...

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SBMO/IEEE MTT-S International Microwave and Optoelectronics Conference

作者： Kleiton de Morais Sousa Uilian Jose Dreyer Cicero Martelli Jean Carlos Cardozo da Silva Federal University of Technology - Parana Graduate Program in Electrical and Computer Engineering

ISBN: (纸本)9781467394932

The vibration in Three-Phase Induction Motors (TIM) is due to mechanical and electrical forces existing during the motor operation. Vibration problems in induction motors can be extremely frustrating and may lead to greatly reduced reliability increasing the maintenance cost. The vibration was measured using fiber Bragg gratings (FBG) installed inside the motor between two stator teeth. The vibration frequencies in TIM are predicted using a model of the forces present in the air gap considering a static and dynamic rotor eccentricity. Two FBGs were positioned between two stator teeth, separated by 120° from each other. The analysis of the vibration spectrum at 60 Hz motor power supply presents the frequencies 60 Hz, 120 Hz, 180 Hz and 240 Hz. This combination of the mechanical and electrical frequencies continue to appear even when the motor electrical supply frequency is reduced by half. The measurement present in this paper can be used to determine some TIM parameters, like the effect of the motor power supply on its vibration signal and also be used like a potential maintenance tool for predictive purposes with high efficiency to continuously monitor the TIM.

关键词： Induction motors Fiber Bragg gratings Motor eccentricity Vibration measurement

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Chemical shift separation with controlled aliasing for hyperpolarized 13C metabolic imaging

Chemical shift separation with controlled aliasing for hyper...

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作者： Shin, Peter J. Larson, Peder E.Z. Uecker, Martin Reed, Galen D. Kerr, Adam B. Tropp, James Ohliger, Michael A. Nelson, Sarah J. Pauly, John M. Lustig, Michael Vigneron, Daniel B. Department of Radiology and Biomedical Imaging University of California at San Francisco 1700 4th Street San FranciscoCA94158 United States UC Berkeley - UCSF Graduate Program in Bioengineering CA United States Department of Electrical Engineering and Computer Sciences University of California at Berkeley BerkeleyCA United States Magnetic Resonance Systems Research Laboratory Department of Electrical Engineering Stanford University StanfordCA United States General Electric Healthcare FremontCA United States

Purpose A chemical shift separation technique for hyperpolarized 13C metabolic imaging with high spatial and temporal resolution was developed. Specifically, a fast three-dimensional pulse sequence and a reconstruction method were implemented to acquire signals from multiple 13C species simultaneously with subsequent separation into individual images. Theory and Methods A stack of flyback echo-planar imaging readouts and a set of multiband excitation radiofrequency pulses were designed to spatially modulate aliasing patterns of the acquired metabolite images, which translated the chemical shift separation problem into parallel imaging reconstruction problem. An eight-channel coil array was used for data acquisition and a parallel imaging method based on nonlinear inversion was developed to separate the aliased images. Results Simultaneous acquisitions of pyruvate and lactate in a phantom study and in vivo rat experiments were performed. The results demonstrated successful separation of the metabolite distributions into individual images having high spatial resolution. Conclusion This method demonstrated the ability to provide accelerated metabolite imaging in hyperpolarized 13C MR using multichannel coils, tailored readout, and specialized RF pulses. © 2014 Wiley Periodicals, Inc.

关键词： Separation

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