检索结果-内蒙古大学图书馆

STEREO VISION CORRESPONDENCE USING A MULTICHANNEL GRAPH MATCHING TECHNIQUE

IMAGE AND VISION COMPUTING 1989年第4期7卷 237-245页

作者： NASRABADI, NM LIU, Y Computer Vision Research Group Department of Electrical Engineering Atwater Kent Laboratories Worcester Polytechnic Institute Worcester MA 01609 USA

A multichannel feature-based stereo vision technique is described in this paper where curve segments are used as the feature primitives in the matching process. Curve segments are extracted by tracking the zero-crossings of the left and right images. The generalized Hough transform of each curve and the curve length are used as a local feature vector in representing the distinctive characteristics of the curve segment. The feature vector of each curve segment in the left image is used as a constraint to find an instance of the same curve segment in the right image. The epipolar constraint on the centroids of the curve segment is used to limit the searching space in the right image. A relational graph is formed from the left image by treating the centroids of the curve segments as the nodes of the graph. The local features of the curve segments are used to represent the local properties of the nodes, and the relationship between the nodes represents the structural properties of the objects in the scene. A similar graph is also formed from the right image curve segments. A graph isomorphism is then formed between the two graphs by using the epipolar constraint on the centroids, the local properties of the nodes, node assignment and the structural relationship (compatibility) between the nodes.

关键词： stereo vision graph matching

来源：评论

学校读者我要写书评

暂无评论

Lessons on mobile apps for COVID-19 from China

引用

Journal of Safety Science and Resilience 2021年第2期2卷 40-49页

作者： Sophia L.Zhou Xianhan Jia Samuel P.Skinner William Yang Isabelle Claude Mass Academy of Math and Science Worcester Polytechnic Institute85 Prescott StreetWorcesterMA 01605United States Department of Computer Science Worcester Polytechnic Institute100 Institute RoadWorcesterMA 01609United States Department of Physics Worcester Polythenic Institute100 Institute RoadWorcesterMA 01609United States Department of Biomedical Engineering Worcester Polytechnic Institute100 Institute RoadWorcesterMA 10609United States

The COVID-19 pandemic has impacted the global society and human life *** countries have launched COVID-19 mobile apps with a wide range in how these apps *** it is hoped that these apps can assist in the fight against COVID-19,many are worried about user *** implemented“health code”systems,which assigned neighborhoods and citizens a specific health code,meant to indicate their risk of having been exposed to *** most widely used health code systems were hosted on the popular apps WeChat and Alipay,each with billions of *** experts argued that China’s use of mobile applications was essential to its successful combat against *** in this study are a summary of mobile technology usage in China,a review of previous studies of mobile technology in healthcare,and a brief survey of some existing mobile applications for COVID-19 that were *** included are outcomes of interviews with healthcare and public safety experts and a public survey to understand how mobile applications were used in China’s response to *** interviews revealed four important themes:personal privacy,community involvement,government involvement,and situational *** was found that a key concern was maintaining a balance between collecting and utilizing personal information,as well as protecting this *** addition,close collaboration between local communities and the national government was *** applications assisted in communication and coordination but did not replace the work of people such as delivery drivers and contact *** results also showed that there was room for improvement,especially accessibility for the elderly or those unfamiliar with *** results were obtained from our *** was interesting to find that the apps were mostly used for“accessing information on COVID-19.”In addition,respondents overwhelmingly identified“information”as the most valuable featur

关键词： Mobile apps COVID-19 response Survey Interview Lessons

来源：评论

学校读者我要写书评

暂无评论

Important considerations in the evaluation of absorbing boundary conditions

引用

ELECTROMAGNETICS 1996年第4期16卷 417-433页

作者： Lee, R Chen, Z Jevtic, JO Lee, JF [a] Department of Electrical Engineering ElectroScience Laboratory The Ohio State University Columbus OH USA [b] Department of Electrical and Computer Engineering Worcester Polytechnic Institute Worcester MA USA

In this paper, we study the interaction of an absorbing boundary condition (ABC) with the discretization error. In many cases the major source of error is due to the discretization error and how it couples to the ABC. In order to study the ABC, we consider three methods to solve the problem. Two of these are finite element methods with either nodal elements or the recently proposed solenoidal elements. The third is based on analytical methods. The effect of electrical size of the geometry as well as the excitation on the error is studied within the context of the interaction between numerical dispersion and the ABC errors.

关键词： Electromagnetic wave absorption

来源：评论

学校读者我要写书评

暂无评论

Response of monkey glabrous skin mechanoreceptors to random noise sequences .3. Spectral analysis

引用

SOMATOSENSORY AND MOTOR RESEARCH 1996年第3-4期13卷 235-244页

作者： Looft, FJ Department of Electrical and Computer Engineering Worcester Polytechnic Institute 100 Institute Road Worcester Massachusetts 01609 fjlooft@ee.wpi.edu

Spectral transfer functions for monkey glabrous skin tactile mechanoreceptors were computed and compared to the results from a dynamic stimulus state analysis for the same receptors. For both sets of experiments, a vibrotactile indenting punctate stimulus driven from a non-repeating-noise (NRN) signal source was used to activate afferents. In all cases, the spectral transfer function results were similar to those inferred from dynamic stimulus state analysis. However, a comparison between the laboratory data and the results from a simple neural model showed that the interpretation of spectral transfer functions is significantly enhanced when compared to the results from an instantaneous state (position, velocity, acceleration) analysis of the stimulus at the time of impulse initiation.

关键词： mechanoreceptors vibrotactile glabrous skin noise stimulus spectral analysis

来源：评论

学校读者我要写书评

暂无评论

RESPONSE OF MONKEY GLABROUS SKIN MECHANORECEPTORS TO RANDOM-NOISE SEQUENCES .1. TEMPORAL RESPONSE CHARACTERISTICS

引用

SOMATOSENSORY AND MOTOR RESEARCH 1994年第4期11卷 327-344页

作者： LOOFT, FJ Department of Electrical and Computer Engineering Worcester Polytechnic Institute Massachusetts 01609 USA.

The response of slowly adapting (SA, Merkel cell), rapidly adapting (RA, Meissner), and Pacinian corpuscle (PC) mechanoreceptors in monkey glabrous skin were recorded while being activated with a vibrotactile indenting stimulus. For one set of experiments, the stimulator was driven by an 800-point (400-msec) pseudorandom-noise (PRN) sequence, repeated 40 times. For a second set of experiments, a non-repeating-noise (NRN) sequence was used. SA impulse patterns generated with the PRN sequence were highly regular and similar for all afferents tested. RA and PC response patterns were more varied, but exhibited basic intraclass similarities. SA and RA PRN stimulus impulse patterns were often nearly indistinguishable at low to medium discharge rates. At higher discharge rates, RA and SA discharge patterns differed, primarily because of the unambiguous suprathreshold velocity sensitivity and shorter recovery periods of RA afferents. PC impulse patterns were substantially different from SA and RA patterns, being clearly dependent on the stimulus velocity at all stimulus intensities. Input-output correlation analysis, coupled with PRN stimulus-response analysis, provided a basis for hypothesizing the basic dynamic encoder function of each type of mechanoreceptor.

关键词： MECHANORECEPTORS VIBROTACTILE GLABROUS SKIN PSEUDORANDOM NOISE

来源：评论

学校读者我要写书评

暂无评论

The effect of receiver diversity combining on optimum energy allocation and energy efficiency of cooperative wireless transmission systems

The effect of receiver diversity combining on optimum energy...

引用

2007 IEEE International Conference on Acoustics, Speech and Signal Processing, ICASSP '07

作者： Jie, Yang Brown III, D. Richard Electrical and Computer Engineering Department Worcester Polytechnic Institute Worcester MA

ISBN: (纸本)1424407281

This paper considers the problem of how to efficiently allocate transmission energy in a cooperative wireless communication system with one source, one relay, and one destination. The relay assists the source via an orthogonal amplify-and-forward protocol. The channels are assumed to be flat fading and the destination combines the source and relay transmissions using either maximal ratio combining (MRC) or equal gain combining (EGC). We analyze the problem of minimizing average total (source plus relay) transmit energy under a fixed outage probability constraint. We show that the choice of receiver diversity combining technique affects both the optimum energy allocation and the overall energy efficiency of the cooperative communication system. Our results show that the ratio of optimum relay to source transmission energy tends to be greater for EGC than MRC. Our results also show that, while cooperative transmission with MRC is always the most efficient strategy, cooperative transmission with EGC tends to be more energy efficient than direct transmission when the outage probability constraint is small or when the relay experiences an advantaged channel to the destination. © 2007 IEEE.

关键词： Wireless networks

来源：评论

学校读者我要写书评

暂无评论

Robot-Assisted Wide-Area Photoacoustic System

Robot-Assisted Wide-Area Photoacoustic System

引用

2023 IEEE International Ultrasonics Symposium, IUS 2023

作者： Gao, Shang Ma, Xihan Zhang, Haichong K. Worcester Polytechnic Institute Department of Robotics Engineering Worcester United States Worcester Polytechnic Institute Department of Biomedical Engineering Worcester United States Worcester Polytechnic Institute Department of Computer Science Worcester United States

ISBN: (纸本)9798350346459

Liver ischemia and reperfusion injury (IRI) is a vascular complication that can lead to hepatic functional impairment. IRI is relevant in liver transplantation and during liver surgery performed with intermittent vascular inflow occlusion. Detecting intraoperative liver oxygenation impairment and ischemia could help prevent IRI, which is challenging partially due to the multiple hepatic vascular inflows. We propose a robot-assisted wide-area photoacoustic (PA) imaging system to monitor the liver oxygenation level intraoperatively. PA imaging has been widely used for oxygenation detection in preclinical research. We used a robotic arm to actuate the 2D PA probe and scan across the liver surface. An accurate volumetric tomography can be reconstructed via registering 2D images to the recorded robot trajectory. An ex vivo porcine liver sample was scanned using the proposed system. The result suggested that the robot-assisted wide-area PA tomography has the potential to be incorporated into clinical practice to evaluate liver SO2 intraoperatively. © 2023 IEEE.

关键词： Photoacoustic effect

来源：评论

学校读者我要写书评

暂无评论

FINITE-ELEMENT FORMULATION OF ACOUSTIC SCATTERING PHENOMENA WITH ABSORBING BOUNDARY-CONDITION IN THE FREQUENCY-DOMAIN

FINITE-ELEMENT FORMULATION OF ACOUSTIC SCATTERING PHENOMENA ...

引用

IEEE 1992 ULTRASONIC SYMP

作者： GAN, H LEVIN, PL LUDWIG, R Department of Electrical and Computer Engineering Worcester Polytechnic Institute Worcester 01609 MA United States

ISBN: (纸本)0780305620

This paper discusses a finite element formulation with an absorbing boundary condition to simulate acoustic scattering phenomena in a general situation, that is, including density as well as sound velocity variations of single and multi-scatterers of arbitrary two dimensional cross sections. In this model, a Galerkin finite element formulation is incorporated with an absorbing boundary operator which explicitly accounts for the open field problem by mapping the Sommerfeld radiation condition from the far field to the near field. By applying the absorbing boundary operator on the artificial boundary of the finite domain, the truncation errors as well as the artifactual reflected power is minimized without compromising the spatsity of the finite element matrix. We compare the numerical results with analytical solutions of cylindrical scatterers of different sizes and at different frequencies. Also, we demonstrate the flexibility of the model by simulating inhomogeneous scatterers and multi-scattering configurations. © 1992 IEEE.

关键词： Boundary conditions

来源：评论

学校读者我要写书评

暂无评论

Assessment of Positioning Errors on V2V Networks Employing Dual Beamforming 88

Assessment of Positioning Errors on V2V Networks Employing D...

引用

88th IEEE Vehicular Technology Conference, VTC-Fall 2018

作者： Kanthasamy, Nivetha Du, Ruixiang Gill, Kuldeep S. Wyglinski, Alexander M. Cowlagi, Raghvendra Department of Electrical and Computer Engineering Worcester Polytechnic Institute WorcesterMA United States Department of Mechanical Engineering Worcester Polytechnic Institute WorcesterMA United States

ISBN: (纸本)9781538663585

In this paper, we present an analysis of Vehicle-to-Vehicle (V2V) Networks employing beamforming at both the transmitter and the receiver when positioning errors are present. Specifically, we will examine the performance of this system setup when the source of the positioning errors are from the Global Positioning System (GPS) measurements as well as from variations in the delays due to the overhead communication channels. To achieve adequate performance, beamforming requires precise location information of the transmitter and the receiver, and when accurate information is unavailable the system performance can potentially deteriorate. This is especially challenging in highly mobile vehicle networking environments where the operating conditions and location information varies rapidly in time. Simulation results are obtained showing Bit Error Rate (BER) values increasing by 99.9% when the exact GPS locations are known by the vehicles when compared to a 6.6m error in GPS location. © 2018 IEEE.

关键词： Global positioning system

来源：评论

学校读者我要写书评

暂无评论

Performance evaluation of the RF receiver for precision positioning system

Performance evaluation of the RF receiver for precision posi...

引用

17th International Technical Meeting of the Satellite Division of the institute of Navigation, ION GNSS 2004

作者： Parikh, Hemish K. Michalson, William R. Duckworth, R. James Electrical and Computer Engineering Department Worcester Polytechnic Institute Worcester Polytechnic Institute ECE Department Worcester Polytechnic Institute WPI Bioengineering Institute Center for Untethered Healthcare

One of the major drivers for developing integrated navigation systems is the vision to provide first responders and healthcare providers, critical information where and when they need it. These integrated wireless devices of the future will assist the user with communications and incident management operations in the field in real time. The most important piece of such a system is clearly a ability to track and locate these wireless devices with high precision in a high-multipath environment. A previous paper presented a novel method for precise geolocation in indoor environments using an orthogonal frequency domain multiplexed (OFDM) signal consisting of many sinusoidal sub-carriers. Unlike the ultra wideband signals that are often proposed for performing precision location in high multipath environments, the proposed signal structure is easily adapted to conform to existing spectral allocations. Further, the signal structure is capable of being used in coded orthogonal frequency domain multiplexing (COFDM) systems for supporting communications and navigation concurrently on the same radio channel. This technique is also well suited for use on ad hoc wireless networks, allowing the precision location of wireless nodes with respect to one another. This OFDM-based technique was first demonstrated using audio frequency signals rather than RF signals and is currently being implemented at RF. The focus of this paper is the design and performance evaluation of the RF front end receiver structure being developed for precision location system using this multi-carrier technique. The effect on the precision of the location estimate due to RF receiver design imperfections will be assessed and design issues for future receiver design improvements will be reviewed.

关键词： Radio receivers

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：