检索结果-内蒙古大学图书馆

作者： Deng, Lei Wang, Chih-Chun Chen, Minghua Zhao, Shizhen Department of Information Engineering Chinese University of Hong Kong Hong Kong Hong Kong School of Electrical and Computer Engineering Purdue University West LafayetteIN47906 United States Google Platform Networking Team Google Inc Mountain ViewCA94043 United States

Most existing wireless networking solutions are best-effort and do not provide any delay guarantee required by important applications, such as mobile multimedia conferencing and real-time control of cyber-physical systems. Recently, Hou and Kumar provided a novel framework for analyzing and designing delay-guaranteed wireless networking solutions. While inspiring, their idle-time-based analysis applies only to flows with a special traffic pattern called the frame-synchronized setting. The problem remains largely open for general traffic patterns. This paper addresses this challenge by proposing a general framework that characterizes and achieves the complete delay-constrained capacity region with general traffic patterns in single-hop downlink access-point wireless networks. We first show that the timely wireless flow problem is fundamentally an infinite-horizon Markov decision process MDP. Then, we judiciously combine different simplification methods to prove that the timely capacity region can be characterized by a finite-size convex polygon. This for the first time allows us to characterize the timely capacity region of wireless flows with general traffic patterns. We then design three scheduling policies to optimize network utility and/or support feasible timely throughput vectors for general traffic patterns. The first policy achieves the optimal network utility and supports any feasible timely throughput vector but suffers from the curse of dimensionality. The second and third policies are inspired by our MDP framework and are of much lower complexity. Simulation results show that both achieve near-optimal performance and outperform other existing alternatives. © 2017 IEEE.

关键词： Markov processes

来源：评论

学校读者我要写书评

暂无评论

Rebuilding the Internet Exchange Point in Uganda

Rebuilding the Internet Exchange Point in Uganda

引用

Irish Signals and Systems Conference (ISSC)

作者： Diarmuid Ó Briain David Denieffe Yvonne Kavanagh Dorothy Okello Department of Electrical and Computer Engineering Makerere University Kampala Uganda Department of Computing & Networking Institute of Technology Carlow Ireland

ISBN: (纸本)9781538622216

Uganda is a land locked country in South East Africa. It is separated from the Indian ocean by Kenya to the east and Tanzania to the south. It is separated from South Atlantic by the Democratic Republic of the Congo to the west. Uganda's connection to the Internet is overland to Mombasa, Kenya where the Seacom cable installed in 2009 connected Mombasa to Europe with a capacity of 640 Gb/s and the World Bank funded Eastern Africa Submarine Cable System (EASSy) undersea fibre optic cable connects Eastern Africa to South Africa and Europe with a capacity of 1.4 Tb/s. [1]. Additionally until recently Uganda was dependent upon a single overland link to Kenya via Uganda Electricity Transmission Company Limited (UETCL) power lines whereas today there are a number of options such as the Seacom cable fibre cable completed in 2015. During the 2010 FIFA World Cup Final a terrorist attack on the Kyandondo Rugby Club in Nakawa, Kampala brought all Internet Service Providers (ISP) in Uganda off-line as the rugby ground sits directly underneath the UETCL power lines bring Internet services from Kenya. This leaves Uganda at significant disadvantage regionally and to-date the technology industry has tended to converge at Mombassa and Nairobi as well as in Dar es Salaam, Tanzania. Recently however as the modern Internet services require Global Service Providers (GSP) to get closer to the end-user so they can avail of lower latency, higher bandwidth applications, the justification for serving all of South East Africa from data centres in Narobi, Mombassa, Dar es Salaam and even from South Africa is becoming less valid. In order to facilitate the deployment of locally hosted content and reduce the country's reliance on international cables, additional capacity was required at the country's primary local interconnection point, the Uganda Internet Exchange Point (UIXP). UIXP is currently developing its infrastructure to support a larger membership encompassing growing demand from both IS

关键词： Routing Servers Protocols Google Europe Web and internet services

来源：评论

学校读者我要写书评

暂无评论

Causes of blindness and vision impairment in 2020 and trends over 30 years, and prevalence of avoidable blindness in relation to VISION 2020: the Right to Sight: an analysis for the Global Burden of Disease Study (vol 2, pg 144, 2021)

引用

LANCET GLOBAL HEALTH 2021年第4期9卷 E408-E408页

作者： Steinmetz, Jaimie D. Vision and Eye Research Institute Anglia Ruskin University Cambridge United Kingdom Biomedical Informatics Seoul National University Hospital Seoul South Korea Institute for Health Metrics and Evaluation University of Washington Seattle WA United States Department of Health Metrics Sciences School of Medicine University of Washington Seattle WA United States Institute of Health Services Research Yonsei University Seoul South Korea Department of Ophthalmology University of Washington Seattle WA United States Department of Mathematics Imperial College London London United Kingdom WHO Collaborating Centre for Public Health Education and Training Imperial College London London United Kingdom Department of Primary Care and Public Health Imperial College London London United Kingdom School of Population and Global Health University of Melbourne Carlton VIC Australia School of Optometry and Vision Science UNSW Sydney NSW Australia Brien Holden Vision Institute Sydney Australia Department of Ophthalmology University of Adelaide Adelaide SA Australia Department of Parasitology and Mycology Jahrom University of Medical Sciences Jahrom Iran Department of Clinical Sciences University of Sharjah Sharjah United Arab Emirates Ophthalmic Research Center Shahid Beheshti University of Medical Sciences Tehran Iran Department of Ophthalmology Shahid Beheshti University of Medical Sciences Tehran Iran Research Institute for Endocrine Sciences Shahid Beheshti University of Medical Sciences Tehran Iran Ophthalmic Epidemiology Research Center Shahid Beheshti University of Medical Sciences Tehran Iran Health Services Management Department Qazvin University of Medical Sciences Qazvin Iran Department of Systems Populations and Leadership University of Michigan Ann Arbor MI United States Department of Medicine Sofia Ismail Memorial Medical Centre Bogura Bangladesh The Fred Hollows Foundation Sydney NSW Australia Berhan Public Health & Eye Care Consultancy Addis A

Hospital El Salvador: a novel paradigm of intensive care in response to COVID-19 in central America. Lancet Glob Health 2021;9: e241?42?In this Comment, the conflict of interest statement should have included the following: ?By virtue of their roles within a public hospital or the Ministry of Health, MB, LC, WH, and XS are government employees. The findings and conclusions in the Comment are only those of the authors.? This correction has been made as of Feb 26, 2021.

关键词：

来源：评论

学校读者我要写书评

暂无评论

Dual core fibers for simultaneously measuring temperature and strain in distributed brillouin sensors 5

Dual core fibers for simultaneously measuring temperature an...

引用

5th Workshop on Specialty Optical Fibers and Their Applications, WSOF 2017

作者： Li, Ming-Jun Stone, Jeffery S. Li, Shenping Zaghloul, Mohamed A. S. Wang, Mohan Chen, Kevin Millione, Giovanni Huang, Yue-Kai Wang, Ting Coring Research and Development Corporation CorningNY14831 United States Department of Electrical and Computer Engineering University of Pittsburgh PittsburghPA15260 United States Optical Networking and Sensing Department NEC Laboratories America Inc. PrincetonNJ08540 United States

We present the design and fabrication of a dual core fiber for separating temperatureand strain effects in distributed Brillouin fiber sensors. Simultaneous measurements oftemperature and strain are demonstrated using... 详细信息

关键词： Time domain analysis

来源：评论

学校读者我要写书评

暂无评论

Forward collision vehicular radar with IEEE 802.11: Feasibility demonstration through measurements

arXiv

引用

arXiv 2017年

作者： Daniels, Robert C. Yeh, Enoch R. Heath, Robert W. Wireless Networking and Communications Group Department of Electrical and Computer Engineering University of Texas at Austin PHAZR Inc.

Increasing safety and automation in transportation systems has led to the proliferation of radar and IEEE 802.11pbased dedicated short range communication (DSRC) in vehicles. Current implementations of vehicular radar devices, however, are expensive, use a substantial amount of bandwidth, and are susceptible to multiple security risks. In this paper, we use the IEEE 802.11 orthogonal frequency division multiplexing (OFDM) communications waveform, as found in IEEE 802.11a/g/p, to perform radar functions. In this paper, we present an approach that determines the mean-normalized channel energy from frequency domain channel estimates and models it as a direct sinusoidal function of target range, enabling closest-target range estimation. In addition, we propose an alternative to vehicular forward collision detection by extending IEEE 802.11 dedicated short-range communications (DSRC) andWiFi technology to radar, extending the foundation of joint communications and radar frameworks. Furthermore, we perform an experimental demonstration near DSRC spectrum using IEEE 802.11 standard compliant sotware defined radios with potentially minimal modification through algorithm processing on frequency-domain channel estimates. The results of this paper show that our solution delivers sufficient accuracy and reliability for vehicular RADAR if we use the largest bandwidth available to IEEE 802.11p (20 MHz). This indicates significant potential for industrial devices with joint vehicular communications and radar capabilities. Copyright © 2017, The Authors. All rights reserved.

关键词： Frequency domain analysis

来源：评论

学校读者我要写书评

暂无评论

Estimates, trends, and drivers of the global burden of type 2 diabetes attributable to PM_2·5 air pollution, 1990–2019: an analysis of data from the Global Burden of Disease Study 2019

引用

The Lancet Planetary Health 2022年第7期6卷 e586-e600页

作者： Burkart, Katrin Causey, Kate Cohen, Aaron J Wozniak, Sarah S Salvi, Devashri Digvijay Abbafati, Cristiana Adekanmbi, Victor Adsuar, Jose C Ahmadi, Keivan Alahdab, Fares Al-Aly, Ziyad Alipour, Vahid Alvis-Guzman, Nelson Amegah, Adeladza Kofi Andrei, Catalina Liliana Andrei, Tudorel Ansari, Fereshteh Arabloo, Jalal Aremu, Olatunde Aripov, Timur Babaee, Ebrahim Banach, MacIej Barnett, Anthony Bärnighausen, Till Winfried Bedi, Neeraj Behzadifar, Masoud Béjot, Yannick Bennett, Derrick A Bensenor, Isabela M Bernstein, Robert S Bhattacharyya, Krittika Bijani, Ali Biondi, Antonio Bohlouli, Somayeh Breitner, Susanne Brenner, Hermann Butt, Zahid A Cámera, Luis Alberto Cantu-Brito, Carlos Carvalho, Felix Cerin, Ester Chattu, Vijay Kumar Chauhan, Bal Govind Choi, Jee-Young Jasmine Chu, Dinh-Toi Dai, Xiaochen Dandona, Lalit Dandona, Rakhi Daryani, Ahmad Davletov, Kairat De Courten, Barbora Demeke, Feleke Mekonnen Denova-Gutiérrez, Edgar Dharmaratne, Samath Dhamminda Dhimal, Meghnath Diaz, Daniel Djalalinia, Shirin Duncan, Bruce B El Sayed Zaki, Maysaa Eskandarieh, Sharareh Fareed, Mohammad Farzadfar, Farshad Fattahi, Nazir Fazlzadeh, Mehdi Fernandes, Eduarda Filip, Irina Fischer, Florian Foigt, Nataliya A Freitas, Marisa Ghashghaee, Ahmad Gill, Paramjit Singh Ginawi, Ibrahim Abdelmageed Gopalani, Sameer Vali Guo, Yuming Gupta, Rajat Das Habtewold, Tesfa Dejenie Hamadeh, Randah R Hamidi, Samer Hankey, Graeme J Hasanpoor, Edris Hassen, Hamid Yimam Hay, Simon I Heibati, Behzad Hole, Michael K Hossain, Naznin Househ, Mowafa Irvani, Seyed Sina Naghibi Jaafari, Jalil Jakovljevic, Mihajlo Jha, Ravi Prakash Jonas, Jost B Jozwiak, Jacek Jerzy Kasaeian, Amir Kaydi, Neda Khader, Yousef Saleh Khafaie, Morteza Abdullatif Khan, Ejaz Ahmad Khan, Junaid Khan, Md Nuruzzaman Khatab, Khaled Khater, Amir M Kim, Yun Jin Kimokoti, Ruth W Kisa, Adnan Kivimäki, Mika Knibbs, Luke D Kosen, Soewarta Koul, Parvaiz A Koyanagi, Ai Defo, Barthelemy Kuate Kugbey, Nuworza Lauriola, Paolo Lee, Paul H Leili, Mostafa Lewycka, Sonia Li, Shanshan Lim, Lee-Ling Li Institute for Health Metrics and Evaluation University of Washington Seattle WA United States Department of Health Metrics Sciences School of Medicine University of Washington Seattle WA United States Division of Plastic and Reconstructive Surgery University of Washington Seattle WA United States Research Insights and Innovation Seattle WA United States Health Effects Institute Boston MA United States School of Public Health Boston University Boston MA United States Department of Juridical and Economic Studies La Sapienza University Rome Italy Department of Population Medicine Cardiff University Cardiff United Kingdom Sport Science Department University of Extremadura Badajoz Spain School of Public Health Imperial College London London United Kingdom Department of Primary Care and Public Health Imperial College London London United Kingdom Mayo Evidence-based Practice Center Mayo Clinic Foundation for Medical Education and Research Rochester MN United States John T. Milliken Department of Internal Medicine Washington University in St. Louis St. Louis MO United States Clinical Epidemiology Center US Department of Veterans Affairs (VA) St Louis MO United States Health Management and Economics Research Center Iran University of Medical Sciences Tehran Iran Department of Health Economics Iran University of Medical Sciences Tehran Iran Preventive Medicine and Public Health Research Center Iran University of Medical Sciences Tehran Iran Pars Advanced and Minimally Invasive Medical Manners Research Center Iran University of Medical Sciences Tehran Iran Department of Community and Family Medicine Iran University of Medical Sciences Tehran Iran Research Group in Hospital Management and Health Policies Universidad de la Costa (University of the Coast) Barranquilla Colombia Research Group in Health Economics University of Cartagena Cartagena Colombia Department of Biomedical Science University of Cape Coast Cape Coast Ghana Cardiology Department Ca

Background: Experimental and epidemiological studies indicate an association between exposure to particulate matter (PM) air pollution and increased risk of type 2 diabetes. In view of the high and increasing prevalence of diabetes, we aimed to quantify the burden of type 2 diabetes attributable to PM_2·5 originating from ambient and household air pollution. Methods: We systematically compiled all relevant cohort and case-control studies assessing the effect of exposure to household and ambient fine particulate matter (PM_2·5) air pollution on type 2 diabetes incidence and mortality. We derived an exposure–response curve from the extracted relative risk estimates using the MR-BRT (meta-regression—Bayesian, regularised, trimmed) tool. The estimated curve was linked to ambient and household PM_2·5 exposures from the Global Burden of Diseases, Injuries, and Risk Factors Study 2019, and estimates of the attributable burden (population attributable fractions and rates per 100 000 population of deaths and disability-adjusted life-years) for 204 countries from 1990 to 2019 were calculated. We also assessed the role of changes in exposure, population size, age, and type 2 diabetes incidence in the observed trend in PM_2·5-attributable type 2 diabetes burden. All estimates are presented with 95% uncertainty intervals. Findings: In 2019, approximately a fifth of the global burden of type 2 diabetes was attributable to PM_2·5 exposure, with an estimated 3·78 (95% uncertainty interval 2·68–4·83) deaths per 100 000 population and 167 (117–223) disability-adjusted life-years (DALYs) per 100 000 population. Approximately 13·4% (9·49–17·5) of deaths and 13·6% (9·73–17·9) of DALYs due to type 2 diabetes were contributed by ambient PM2·5, and 6·50% (4·22–9·53) of deaths and 5·92% (3·81–8·64) of DALYs by household air pollution. High burdens, in terms of numbers as well as rates, were estimated in Asia, sub-Saharan Africa, and South Am

关键词：

来源：评论

学校读者我要写书评

暂无评论

Internet of Things — Propagation modelling for precision agriculture applications

Internet of Things — Propagation modelling for precision ag...

引用

Wireless Telecommunications Symposium, WTS

作者： Jacqueline Stewart Robert Stewart Sean Kennedy Department of Electronics Computer and Software Engineering The Wireless Networking Group Athlone Institute of Technology Athlone County Westmeath Ireland

ISBN: (纸本)9781509036004

The ubiquitous deployment of IEEE 802.11 based Wireless Mesh Networks (WMNs) has facilitated non-real-time applications effectively to date. However the advancement in IEEE 802.15.4 Wireless Sensor Network (WSN) technology has dramatically increased the volume and range of applications available under the umbrella of the Internet of Things (IoTs). Such applications cross the divide of simple environmental data collectors to highly specific multimedia real-time applications demanding high Quality of Service (QoS) guarantees. However delivering QoS guarantees is difficult to achieve when deployed in a hostile environment such as that found in the Precision Agriculture (PA) industry. Difficulties in wireless propagation attenuation delivers an uncertainty to the network design phase. Therefore the motivation of this research is a requirement for real-time characterisation and derivation of suitable propagation models to support network design and deployment planning. In this work, empirical results were collected from a heterogeneous wireless deployment (the real-world ECOMESH test-bed) in a native woodland environment. We derive two empirical models which can be utilised in predicting attenuation network performance in two different scenarios. These models deliver the first phase of a Dynamic Network Management System for maintaining QoS guarantees in heterogeneous wireless networks.

关键词： Wireless sensor networks Biological system modeling Vegetation mapping Vegetation Wireless communication Mathematical model Agriculture

来源：评论

学校读者我要写书评

暂无评论

An analytical framework for modeling a spatially repulsive cellular network

arXiv

引用

arXiv 2017年

作者： Choi, Chang-Sik Oh Woo, Jae Andrews, Jeffrey G. Wireless and Networking and Communication Group Department of Electrical and Computer Engineering The University of Texas at Austin Texas78701 United States

We propose a new cellular network model that captures both deterministic and random aspects of base station deployments. Namely, the base station locations are modeled as the superposition of two independent stationary point processes: a random shifted grid with intensity λg and a Poisson point process (PPP) with intensity λp. Grid and PPP deployments are special cases with λp → 0 and λg → 0, with actual deployments in between these two extremes, as we demonstrate with deployment data. Assuming that each user is associated with the base station that provides the strongest average received signal power, we obtain the probability that a typical user is associated with either a grid or PPP base station. Assuming Rayleigh fading channels, we derive the expression for the coverage probability of the typical user, resulting in the following observations. First, the association and the coverage probability of the typical user are fully characterized as functions of intensity ratio ρλ = λp/λg. Second, the user association is biased towards the base stations located on a grid. Finally, the proposed model predicts the coverage probability of the actual deployment with great accuracy. Copyright © 2017, The Authors. All rights reserved.

关键词： Internet protocols

来源：评论

学校读者我要写书评

暂无评论

An RSSI-based Distributed Real-time Indoor Positioning Framework

An RSSI-based Distributed Real-time Indoor Positioning Frame...

引用

International Conference on Applied System Innovation

作者： Wen-Ching Chen Kuo-Fong Kao Yung-Tsang Chang Chih-Hung Chang Department of Information Networking Technology Hsiuping University of Science and Technology Taichung City Taiwan Department of Computer Science and Communication Engineering PROVIDENCE UNIVERSITY Shalu Dist. Taichung City Taiwan

In recent years, the application of indoor positioning and tracking have become more important, which may be applied to the navigation of large building, personnel tracking, etc. Due to the limitations of GPS, some researchers have utilized the received signal strength indicator (RSSI) in the wireless environment for indoor positioning. There are two major approaches are proposed: fingerprinting and trilateration techniques. In this research, we proposed an RSSI-based Distributed Real-time Indoor Positioning Framework which integrated these two techniques to construct a cost-effective solution in Bluetooth low energy environment.

关键词： RSSI Indoor positioning Trilateration Kalman filter

来源：评论

学校读者我要写书评

暂无评论

Mobile Edge computing empowers Internet of Things

arXiv

引用

arXiv 2017年

作者： Ansari, Nirwan Sun, Xiang Advanced Networking Lab Department of Electrical & Computer Engineering New Jersey Institute of Technology NewarkNJ07102 United States

In this paper, we propose a Mobile Edge Internet of Things (MEIoT) architecture by leveraging the fiber-wireless access technology, the cloudlet concept, and the software defined networking framework. The MEIoT architecture brings computing and storage resources close to Internet of Things (IoT) devices in order to speed up IoT data sharing and analytics. Specifically, the IoT devices (belonging to the same user) are associated to a specific proxy Virtual Machine (VM) in the nearby cloudlet. The proxy VM stores and analyzes the IoT data (generated by its IoT devices) in real-time. Moreover, we introduce the semantic and social IoT technology in the context of MEIoT to solve the interoperability and inefficient access control problem in the IoT system. In addition, we propose two dynamic proxy VM migration methods to minimize the end-to-end delay between proxy VMs and their IoT devices and to minimize the total on-grid energy consumption of the cloudlets, respectively. Performance of the proposed methods is validated via extensive simulations. Copyright © 2017, The Authors. All rights reserved.

关键词： Semantics

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：