检索结果-内蒙古大学图书馆

2013 IEEE International Conference on Automation Science and engineering, CASE 2013

作者： Hu, Hesuan Zhou, Mengchu Liu, Yang School of Electro-mechanical Engineering Xidian University Xi'an Shaanxi 710071 China School of Computer Engineering Nanyang Technological University Singapore 639798 Singapore Key Laboratory of Embedded System and Service Computing Ministry of Education Tongji University Shanghai 201804 China Department of Electrical and Computer Engineering New Jersey Institute of Technology Newark NJ 07102 United States

ISBN: (纸本)9781479915156

Behavior management and performance evaluation are two significant issues in the design and operation of automated manufacturing systems (AMS). The former constrains their dynamics so as to avoid improper behavior and eliminate downtime, while the latter aims to evaluate cycle time. Although abundant research has been conducted on each issue independently, researchers rarely address both in a correlative way. Without accurate and prompt guidance to route parts, it is difficult for an AMS to manage the production process in an optimal manner. In the paradigm of Petri nets, we show that it is crucial to optimize certain local priorities for the sake of cycle time minimization or throughput maximization. Without making radical changes to the system structure, our method can well design some control parameters in order to meet system performance requirement. An algorithm of polynomial complexity is presented to derive supervisory controllers, if existing, to improve system performance. © 2013 IEEE.

关键词： Petri nets

来源：评论

学校读者我要写书评

暂无评论

Maximally permissive distributed control of large scale automated manufacturing systems modeled with Petri nets

Maximally permissive distributed control of large scale auto...

引用

2013 IEEE International Conference on Automation Science and engineering, CASE 2013

ISBN: (纸本)9781479915156

Ensuring nonblockingness remains challenging for automated manufacturing systems (AMS) owing to their discrete event dynamics. Both scalability and maximal permissiveness are essential for the synthesis and implementation of their centralized supervisors. Inspired by the divide and conquer philosophy, this work proposes a partition methodology and distributed control technique for large scale AMS. They are represented as interconnected and overlapping subsystems sharing some common components in terms of buffers. For each subsystem, a local supervisor is designed based on its local behavior and neighboring information only. Generalizing the existing results, we develop a condition under which the control law via decomposition promises the maximal permissiveness. Buffer capacities are well designed for the sake of their decomposition into multiple overlapping subsystems. Theoretical results are developed to characterize the behavior compatibility among local controllers. An experimental study illustrates the effectiveness of the proposed method. © 2013 IEEE.

关键词： Supervisory personnel

来源：评论

学校读者我要写书评

暂无评论

Dynamic monitoring of optimal locations in road network databases

引用

The VLDB Journal 2013年第5期23卷 697-720页

作者： Bin Yao Xiaokui Xiao Feifei Li Yifan Wu Department of Computer Science and Engineering Shanghai Key Laboratory of Scalable Computing and Systems Shanghai Jiao Tong University Shanghai China School of Computer Engineering Nanyang Technological University Singapore Singapore School of Computing University of Utah Salt Lake City USA

Optimal location (OL) queries are a type of spatial queries that are particularly useful for the strategic planning of resources. Given a set of existing facilities and a set of clients, an OL query asks for a location to build a new facility that optimizes a certain cost metric (defined based on the distances between the clients and the facilities). Several techniques have been proposed to address OL queries, assuming that all clients and facilities reside in an $$L_p$$ space. In practice, however, movements between spatial locations are usually confined by the underlying road network, and hence, the actual distance between two locations can differ significantly from their $$L_p$$ distance. Motivated by the deficiency of the existing techniques, this paper presents a comprehensive study on OL queries in road networks. We propose a unified framework that addresses three variants of OL queries that find important applications in practice, and we instantiate the framework with several novel query processing algorithms. We further extend our framework to efficiently monitor the OLs when locations for facilities and/or clients have been updated. Our dynamic update methods lead to efficient answering of continuous optimal location queries. We demonstrate the efficiency of our solutions through extensive experiments with large real data.

关键词：

来源：评论

学校读者我要写书评

暂无评论

Rate adaptation and base station reconfiguration for battery efficient video download

Rate adaptation and base station reconfiguration for battery...

引用

IEEE Conference on Wireless Communications and Networking

作者： Ranjini Guruprasad Sujit Dey Mobile Systems Design Laboratory Department of Electrical and Computer Engineering University of California San Diego USA

ISBN: (纸本)9781467359382

With increasing usage of mobile devices to watch mobile video, the battery consumption of mobile devices will be dominated by video delivery and playback. In this paper, we develop battery efficient video delivery techniques that vary video transmission rate dynamically depending on battery and buffer levels of the mobile device, the channel conditions experienced, and video quality requirements while maximizing battery life and ensuring user experience. The proposed dynamic video rate adaptation techniques enable the base station to adapt the Multi Input Multi Output (MIMO) transceiver configurations to reduce battery current required by MIMO components on the mobile device. The proposed techniques also make the base station stop video transmission opportunistically, thereby eliminating the battery load imposed by the mobile MIMO components. Experiments conducted under various network conditions for various video download profiles show that more than 50% improvement in battery lifetime is possible in comparison to conventional video download techniques not aware of battery.

关键词： Batteries Streaming media Bit error rate MIMO Decoding Mobile handsets Signal to noise ratio

来源：评论

学校读者我要写书评

暂无评论

Index Policies for Demand Response Under Uncertainty

Index Policies for Demand Response Under Uncertainty

引用

IEEE Annual Conference on Decision and Control

作者： Joshua A. Taylor Johanna L. Mathieu Department of Electrical and Computer Engineering at the University of Toronto Canada Power Systems Laboratory at ETH Zurich Switzerland

ISBN: (纸本)9781467357159

Uncertainty is an intrinsic aspect of demand response because electrical loads are subject to many random factors and their capabilities are often not directly measurable until they have been deployed. Demand response algorithms must therefore balance utilizing well-characterized, good loads and learning about poorly characterized but potentially good loads;this is a manifestation of the classical tradeoff between exploration and exploitation. We address this tradeoff in a restless bandit framework, a generalization of the well-known multi-armed bandit problem. The formulation yields index policies, in which loads are ranked by a scalar index and those with the highest are deployed. The policy is particularly appropriate for demand response because the indices have explicit analytical expressions that may be evaluated separately for each load, making them both simple and scalable. We numerically evaluate the performance of the index policy, and discuss implications of the policies in demand response.

关键词： Demand-Responsive Policies LOAD tradeoffs Uncertainty

来源：评论

学校读者我要写书评

暂无评论

Reconstruction of directed acyclic networks of dynamical systems

Reconstruction of directed acyclic networks of dynamical sys...

引用

American Control Conference

作者： Donatello Materassi Murti V. Salapaka Laboratory for Information and Decision Systems Massachusetts Institute of Technology Department of Electrical and Computer Engineering University of Minnesota

ISBN: (纸本)9781479901777

Determining the relation structure of various interconnected entities from multiple time series data is of significant interest to many areas. Knowledge of such a structure can aid in identifying cause and effect relationships, clustering of similar entities, detecting representative elements for an aggregate and determining reduced order models. Current methods tend to treat observations in a static manner by modeling the measured time series as repeated realizations of as many random variables that are independent over time. This amounts to assume static relationships among the measurements, making these techniques ill-suited for detecting propagative and dynamic phenomena that can be fundamental for the understanding of the system. In this paper we extend techniques for the identification of networks of random variables connected through static relations to the case of random processes with dynamic relations. This is achieved by showing that the Wiener filter defines a relationship among jointly stationary stochastic processes that has the properties of a semi-graphoid.

关键词： acyclic network Random variable DYNAMICAL systems Stochastic Processes Wiener filters dynamic phenomenon time series data Reduced order model Mentoring

来源：评论

学校读者我要写书评

暂无评论

Application of Time Series and Artificial Neural Network Models in Short-term Forecasting of PV Power Generation

Application of Time Series and Artificial Neural Network Mod...

引用

International Universities Power engineering Conference

作者： E. G. Kardakos M. C. Alexiadis S. I. Vagropoulos C. K. Simoglou P. N. Biskas A. G. Bakirtzis Power Systems Laboratory Department of Electrical and Computer Engineering Aristotle University of Thessaloniki 54124 Thessaloniki GREECE

ISBN: (纸本)9781479932559

This paper addresses two practical methods for electricity generation forecasting of grid-connected PV plants. The first model is based on seasonal ARIMA time-series analysis and is further improved by incorporating short-term solar radiation forecasts derived from NWP models. The second model adopts artificial neural networks with multiple inputs. Day-ahead and rolling intra-day forecast updates are implemented to evaluate the forecasting errors. All models are compared in terms of the Normalized (with respect to the PV installed capacity) Root Mean Square Error (NRMSE). Simulation results from the application of the forecasting models in different PV plants of the Greek power system are presented.

关键词： Artificial neural networks autoregressive integrated moving average (ARIMA) models day-ahead forecasting photovoltaic plants solar radiation

来源：评论

学校读者我要写书评

暂无评论

A performance comparison of DTN protocols for high delay optical channels

A performance comparison of DTN protocols for high delay opt...

引用

IEEE Wireless Communications and Networking Conference Workshops (WCNCW)

作者： Paul Muri Janise McNair Department of Electrical and Computer Engineering Wireless and Mobile Systems Laboratory University of Florida Gainesville FL USA

Designed for long propagation delay and frequent channel disruptions, delay tolerant networking (DTN) protocols are supporting the latest proposed optical space internetworking communication missions. While previous DTN-based testbeds experimented with bandwidth capacity in megabits, this paper presents a channel emulation testbed that supports multiple gigabit-bandwidth Ethernet clients and servers simultaneously. In addition to capacity, this testbed modeled optical link properties with channel emulation, and provided high flexibility by utilizing virtual LANs and link aggregation connected through a gigabit switch. The testbed emulated propagation delay, asynchronous channel rates, and bit errors, including free-space optical bit errors that varied as a function of time. We emulated an optical flight terminal relaying data between ground stations, and measured the maximum goodput of various DTN configurations while increasing the relay's round trip times. Results showed that for a 200 ms to one second round trip time, BP/TCPCL/TCP transmitted higher goodput than BP/LTP/UDP, and TCP/IP. For round trip times longer than one second, BP/LTP/UDP transmitted higher goodput than BP/TCPCL/TCP, and TCP/IP.

关键词： Protocols Delays Adaptive optics Optical fiber communication Bandwidth IP networks Emulation

来源：评论

学校读者我要写书评

暂无评论

Adaptive Bit Rate capable video caching and scheduling

Adaptive Bit Rate capable video caching and scheduling

引用

IEEE Conference on Wireless Communications and Networking

作者： Hasti Ahlehagh Sujit Dey Mobile Systems Design Laboratory Department of Electrical and Computer Engineering University of California San Diego USA

ISBN: (纸本)9781467359382

Adaptive Bit Rate Streaming (ABR) has become a popular video delivery technique, credited to improving the quality of delivered video on wireless networks. At the same time, recent research has shown video caching in the Radio Access Network (RAN) can be a promising way to increase capacity of the network while reducing video latency and improving video quality of experience. In this work, we investigate the opportunities and challenges of combining the advantages of ABR streaming and RAN caching to maximize the video capacity of wireless networks. Since with ABR, each video is divided into multiple segments, chunks, and each chunk can be requested at different bit rates, the caching requirements are very different and challenging; a cache hit will require not only the presence of a specific video chunk, but also the availability of the desired bit rate. One way to solve this problem is to cache all variants of a video, but this approach may significantly increase storage and backhaul requirements or reduce the number of unique videos that can be cached. In this paper, we introduce a framework consisting of rate adaptation algorithm, video caching and processing within the wireless cloud, with the aim to improve video capacity of the wireless network and satisfy or exceed QoE of each video request. To achieve this goal, we propose a new ABR algorithm, along with an ABR aware Least Recently Used (LRU) caching policy with Processing (ABRLRU-P) to support caching of video chunks with different bit rates. Using our MATLAB statistical simulation framework, we demonstrate a capacity improvement of up to 83% when ABR is used with RAN caching and processing using the ABR-LRU-P policy compared with using no RAN caching and video processing. Further, using ABR along with ABRLRU-P caching policy can improve the capacity by 68% compared with using ABR and a straightforward static LRU caching policy which fetches all video bit rate versions of a video chunk upon a cache miss.

关键词： Streaming media Bit rate Delays Wireless networks Radio access networks Bandwidth

来源：评论

学校读者我要写书评

暂无评论

A Smartphone Localization Algorithm Using RSSI and Inertial Sensor Measurement Fusion

A Smartphone Localization Algorithm Using RSSI and Inertial ...

引用

IEEE Global Communications Conference

作者： William Wei-Liang Li Ronald A. Iltis Moe Z. Win Department of Electrical and Computer Engineering University of California Laboratory for Information and Decision Systems Massachusetts Institute of Technology

ISBN: (纸本)9781479913510

Indoor navigation using the existing wireless infrastructure and mobile devices is a very active research area. The major challenge is to leverage the extensive smartphone sensor suite to achieve location tracking with high accuracy. In this paper, we develop a navigation algorithm which fuses the WiFi received signal strength indicator (RSSI) and smartphone inertial sensor measurements. A sequential Monte Carlo filter is developed for inertial sensor based tracking, and a radiolocation algorithm is developed to infer mobile location based on RSSI measurements. The simulation results show that the proposed algorithm significantly outperforms the extended Kalman filter (EKF), and achieves competitive location accuracy compared with the round trip time (RTT) based ultra-wideband (UWB) system.

关键词： Indoor navigation Smartphone localization Inertial measurement unit (IMU) Particle filter Information fusion Received Signal Strength Indicator Information fusion Indoor navigation Particle filters Smartphone Inertial Location tracking Sensors positioning accuracy Wi-Fi

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：