检索结果-内蒙古大学图书馆

Wireless Telecommunications Symposium, WTS

作者： Antonios Alexiou Christos Bouras Vasileios Kokkinos Andreas Papazois Georgia Tseliou Computer Engineering and Informatics Department University of Patras Greece Research Academic Computer Technology Institute Patras Greece

The 3rd Generation Partnership Project (3GPP) has introduced the evolved Multimedia Broadcast/Multicast Service (e-MBMS) feature for cellular systems as an evolution to the existing MBMS service. To support e-MBMS in Long Term Evolution (LTE) systems, 3GPP recommends the use of Point-to-Multipoint (PTM) transmissions and MBMS over a Single Frequency Network (MBSFN). MBSFN is a new feature where a time-synchronized common waveform is transmitted from multiple cells. In this paper we investigate the provision of MBMS service over a combination of MBSFN and PTM transmission methods. A cost analysis of the MBMS service is presented based on the transmission cost over all the interfaces and nodes of the LTE architecture. We evaluate the performance of this transmission scheme from telecommunication cost perspective and we compare it with other transmission schemes. The performance evaluation has been performed with the aid of a new simulation tool that estimates the cost for the MBMS provision under different network topologies, MBSFN deployments and user distributions.

关键词： Synchronization Topology Equations computer architecture Multimedia communication Algorithms

来源：评论

学校读者我要写书评

暂无评论

Introducing agent evictions to improve application placement in wireless distributed systems

Introducing agent evictions to improve application placement...

引用

41st International Conference on Parallel Processing, ICPP 2012

作者： Tziritas, Nikos Lampsas, Petros Lalis, Spyros Loukopoulos, Thanasis Khan, Samee Ullah Xu, Cheng-Zhong Shenzhen Institutes of Advanced Technology Chinese Academy of Sciences Shenzhen 518067 China Dept. of Informatics and Computer Technology Technological Educational Institute of Lamia Lamia Greece Computer and Communication Engineering Dept. University of Thessaly Volos Greece Department of Electrical and Computer Engineering North Dakota State University Fargo ND 58108-6050 United States Department of Electrical and Computer Engineering Wayne State University Detroit MI 48202 United States Center for Research and Technology Institute of Thessaly Volos Greece

ISBN: (纸本)9780769547961

With the development of mobile code frameworks for embedded systems, an application can be structured as a set of cooperating components (agents) that are placed on the nodes of the system in a flexible way. Reducing the network traffic caused by the application components is a crucial issue for the increase in the lifetime of wireless embedded systems, since it is widely known that the communication cost plays the most significant role in the energy consumption of embedded devices. To this end, most placement algorithms place or move an agent towards the center of gravity of the communication workload. However, if the target node does not have enough capacity, the attempt is usually aborted. In this paper, we introduce eviction-enabled algorithms that allow nodes to free capacity by forcing a locally hosted agent to move to another node, even at a loss, to accept a new and potentially more beneficial agent. To the best of our knowledge, this is the first time that agents are evicted by local hosts to enable beneficial agent migrations and eventually improve the total network cost. In this paper, we provide algorithms tackling the aforementioned problem in a fully distributed manner. We also present and discuss the results of extensive simulations, showing that eviction-enabled algorithms can outperform their counterparts by up to 300%. © 2012 IEEE.

关键词： Mobile agents

来源：评论

学校读者我要写书评

暂无评论

Modeling the Health Status of a Ball Bearing for Predictive Maintenance Purposes

Modeling the Health Status of a Ball Bearing for Predictive ...

引用

International Conference on Control, Decision and Information Technologies (CoDIT)

作者： Elisavet Karapalidou Agisilaos Efraimidis Stavros Vologiannidis Efstathios Antoniou Department of Computer Informatics and Telecommunications Engineering International Hellenic University Terma Magnisias Serres Greece Department of Informatics and Electronics Engineering International Hellenic University Thessaloniki Greece

Modern industries are constantly aiming to maximize utilization and performance of their machine equipment and minimize costly and unscheduled downtime. In the recent years, this was made possible with the advancement of technology and the coming of the fourth industrial revolution, also known as Industry 4.0, which introduced the Internet of Things and Artificial Intelligence systems in industrial applications. This allowed the employment of predictive maintenance methods able to assess the health of the equipment and diagnose possible future failures. In this work, an experimental assembly was constructed comprised by an electrical motor, a reduction gear, an axle, a coupler, a bearing and a vibration sensor attached to the latter. Three types of experiments were conducted for the purpose of producing a labeled dataset based on vibration measurements. Specifically, measurements were made during the bearing's working in normal operating state, one with lack and one with excess amount of grease. A preliminary statistical analysis was performed while a Multilayer Perceptron model was employed to automatically predict the status of the bearing. The dataset is freely available at the Zenodo data repository.

关键词：

来源：评论

学校读者我要写书评

暂无评论

Low power dissipation in BIST schemes for modified Booth multipliers

Low power dissipation in BIST schemes for modified Booth mul...

引用

IEEE International Symposium on Defect and Fault Tolerance in VLSI Systems

作者： D. Bakalis H.T. Vergos D. Nikolos X. Kavousianos G.Ph. Alexiou Department of Computer Engineering & Informatics University of Patras Rio-Patras Greece Computer Technology Institute Patras Greece

ISBN: (纸本)076950325X

Aiming at low power dissipation during testing, in this paper we present a methodology for deriving a novel BIST scheme for modified Booth multipliers. Reduction of the power dissipation is achieved by: (a) introducing a suitable test pattern generator (TPG) built of a 4-bit binary and a 4-bit Gray counter, (b) properly assigning the TPG outputs to the multiplier inputs and (c) significantly reducing the test set length. The achieved reduction of the total power dissipation is from 44.1% to 54.9%, the average reduction per test vector is from 21.4% to 36.5% while the reduction of the peaks is from 15.8% to 34.3%, depending on the implementation of the basic cells and the size of the MBM. The test application time is also reduced by 28.9% while the introduced BIST scheme implementation overhead is very small.

关键词： Power dissipation Built-in self-test Circuit testing Logic testing Costs System testing Circuit faults Packaging Power engineering and energy informatics

来源：评论

学校读者我要写书评

暂无评论

Performance Evaluation of Node Architectures with Color and Direction Constraints in WDM Networks

Performance Evaluation of Node Architectures with Color and ...

引用

2010 IEEE Global Telecommunications Conference GLOBECOM 2010

作者： Konstantinos Manousakis Panagiotis Kokkinos Emmanouel Varvarigos Computer Engineering and Informatics Department University of Patras Greece Research Academic Computer Technology Institute Patras Greece

We consider routing and wavelength assignment (RWA) in a WDM network consisting of optical cross-connect (OXC) nodes that have color and direction constraints. These restricted node architectures have a smaller cost than the more flexible (and best performing) ones usually assumed in the RWA problem. This introduces an interesting tradeoff between the network performance achieved, in terms of network blocking and number of manual interventions required, and the cost of the node architecture used. In the process of comparing the node architectures, we propose an adaptation of an RWA algorithm that accounts for the lack of node flexibility, aiming to achieve using the constrained node architectures, performance similar to that obtained with the fully flexible node architectures. Additionally, we consider different transponder assignment policies and determine their effect on performance.

关键词： Peer to peer computing Optical fiber networks Availability Transponders Fiber optics computer architecture

来源：评论

学校读者我要写书评

暂无评论

Secure mmWave-NOMA Multi-BS Vehicular Communications Using Cooperative Jamming

Secure mmWave-NOMA Multi-BS Vehicular Communications Using C...

引用

2024 IEEE Global Communications Conference, GLOBECOM 2024

作者： Yan, Yiting Ju, Ying Hu, Jiawei Liu, Lei Pei, Qingqi Yau, Kok-Lim Alvin Wu, Celimuge Zhang, Ning Xidian University School of Telecommunications Engineering Xi'an710071 China Universiti Tunku Abdul Rahman School of Internet Engineering and Computer Science Selangor 43200 Malaysia The University of Electro-Communications Graduate School of Informatics and Engineering Tokyo182-8585 Japan University of Windsor Department of Electrical and Computer Engineering WindsorN9B-3P4 Canada

ISBN: (纸本)9798350351255

The fronthaul network architecture is the key to dealing with the massive traffic effectively and providing high-quality service, and the multiple base stations (BSs) deployed by it face the gigantic data transmission, which has given the demand for high-capacity communication and information security in the vehicular network. In this paper, we combine the millimeter wave (mmWave) communication and non-orthogonal multiple access (NOMA) technologies to escalate the communication capacity of multiple vehicle users (VUs), and propose a blockage-based cooperative jamming strategy to solve potential security risks in the vehicular network. In particular, with the help of jam-mers selected by this strategy, transmission security is enhanced simultaneously without escalating the instability of connections caused by the time-varying nature of vehicular networks under the NOMA transmission mechanism when the base station (BS) does not fully understand the channel state information (CSI) of VUs. Then we comprehensively analyze the specific distribution of roadways and the distance distribution of VUs under the NOMA strategy, and derive the performance metrics of the network based on the stochastic geometry method. Numerical results show that the proposed cooperative jamming scheme can effectively improve the secrecy performance of the vehicular network. © 2024 IEEE.

关键词： Jamming

来源：评论

学校读者我要写书评

暂无评论

Customized toolbox in VR Design 22

Customized toolbox in VR Design

引用

Proceedings of the 26th Pan-Hellenic Conference on informatics

作者： Georgia Drampalou Nikolaos Kourniatis Ioannis Voyiatzis Department of Informatics and Computer Engineering University of West Attica Greece Department of Civil Engineering University of West Attica Greece

ISBN: (纸本)9781450398541

Designing in an environment of Virtual Reality is a field that gains ground. Although more and more applications are constantly released, the majority of designers have not yet been introduced into Virtual Reality. A widely used tool for designing is Rhino which has been released by McNeel and Rhino Developer encourages the users to create plug-ins for custom use of the software. In parallel, Meta's developing tools offer their users the chance to customize their own applications. Towards the direction of Virtual Reality integration, both have already released new products for their users. RhinoVR is an open source plug-in for Rhino, while at the same time Meta provides Oculus hardware and platform solutions for users to turn their concept into reality. What is yet to be developed is a model that encourages the customization of a VR design platform, focusing mainly on developing a personalized toolbox for designing.

关键词： plug-in SDK Rhino Developer Oculus Quest 2 VR Design OpenVR API

来源：评论

学校读者我要写书评

暂无评论

Efficient sequential pattern mining with wildcards for keyphrase extraction

引用

Knowledge-Based Systems 2017年 115卷 27-39页

作者： Xie, Fei Wu, Xindong Zhu, Xingquan School of Computer Science and Information Engineering Hefei University of Technology Hefei 230009 China Department of Computer Science and Technology Hefei Normal University Hefei 230601 China School of Computing and Informatics University of Louisiana at Lafayette LA 70503 United States Dept. of Computer & Electrical Eng. and Computer Science Florida Atlantic Univ. Boca Raton FL 33431 United States

A keyphrase (a multi-word unit) in a document denotes one or multiple keywords capturing a main topic of the underlying document. Finding good keyphrases of a document can quickly summarize knowledge for efficient decision making and benefit domains involving intensive text information. To date, existing keyphrase extraction methods cannot be customized to each specific document, mainly because their patterns used to form paraphrases are too restrictive and may not capture flexible keyword relationships inside the text. In this paper, we propose a sequential pattern mining based document-specific keyphrase extraction method. Our key innovation is to use wildcards (or gap constraints) to help extract sequential patterns, so the flexible wildcard constraints within a pattern can capture semantic relationships between words, and the system will have full flexibility to discover different types of sequential patterns as candidates for keyphrase extraction. To achieve the goal, we regard each single document as a sequential dataset, and propose an efficient algorithm to mine sequential patterns with wildcard and one-off conditions that allows important keyphrases to be captured during the mining process. For each extracted keyphrase candidate, we use some statistical pattern features to characterize it, and further collect all keyphrases from the document to form a training set. A supervised learning classifier is trained to identify keyphrases from a test document. Because our pattern mining and pattern characterization processes are customized to each single document, keyphases extracted from our method are highly specific for each document. Experimental results demonstrate that the proposed sequential pattern mining method outperforms existing pattern mining methods in both runtime performance and completeness. Comparisons on keyphrase benchmark datasets also confirm that the proposed document-specific keyphrase extraction method is effective in improving the quality

关键词： Classification Document summarization Keyphrase extraction Sequential pattern mining Wildcards

来源：评论

学校读者我要写书评

暂无评论

Enhancing reliable mobile multicasting with RaptorQ FEC

Enhancing reliable mobile multicasting with RaptorQ FEC

引用

IEEE Symposium on computers and Communications (ISCC)

作者： Christos Bouras Nikolaos Kanakis Vasileios Kokkinos Andreas Papazois Computer Engineering and Informatics Department University of Patras Greece Computer Technology Institute CTI Greece Patras Greece

A crucial point on the successful deployment of multicast services is the enhanced reliability by means of advanced error control schemes. To this direction Third Generation Partnership Project (3GPP) has standardized exclusively for Multimedia Broadcast/Multicast Services (MBMS) the use of a Forward Error Correction (FEC) mechanism on the application layer based on Raptor codes. Since the standardized systematic, fountain Raptor code is now considered obsolete, the emergence of a new variant of Raptor codes, named RaptorQ, provides enhanced capabilities for mobile multicast services. In this paper, we provide a performance comparison of the standardized Raptor Application Layer FEC (AL-FEC) scheme with the very promising RaptorQ FEC code. We examine the enhancements that RaptorQ introduces on the AL-FEC protection robustness, providing a thorough performance analysis in comparison with the current Raptor FEC scheme. Furthermore, in order to verify the improved performance of RaptorQ, we provide several simulation results utilizing the ns-3 environment, considering the application of both the examined AL-FEC schemes over multicast services for next generation mobile networks.

关键词： Encoding Forward error correction Decoding Mobile communication Maintenance engineering Delay Reliability

来源：评论

学校读者我要写书评

暂无评论

Algorithmic aspects of optical network design

Algorithmic aspects of optical network design

引用

International Conference on Optical Network Design and Modeling, ONDM

作者： E. A. Varvarigos K. Christodoulopoulos Computer Engineering and Informatics Department University of Patras Greece Research Academic Computer Technology Institute Patra Greece

Optical network design problems fall in the broad category of network optimization problems. We give a short introduction on network optimization and general algorithmic techniques that can be used to solve complex and difficult network design problems. We apply these techniques to address the static Routing and Wavelength Assignment problem that is related to planning phase of a WDM optical network. We present simulation result to evaluate the performance of the proposed algorithmic solution.

关键词： Algorithm design and analysis Cost function Polynomials Optical fiber networks WDM networks Routing

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：