检索结果-内蒙古大学图书馆

International Symposium on Code Generation and Optimization (CGO)

作者： Gabriel Rodríguez José M. Andión Mahmut T. Kandemir Juan Touriño Dep. Electrónica e Sistemas Universidade da Coruña A Coruña Spain Department of Computer Science and Engineering The Pennsylvania State University University Park PA USA

Complete comprehension of loop codes is desirable for a variety of program optimizations. Compilers perform static code analyses and transformations, such as loop tiling or memory partitioning, by constructing and manipulating formal representations of the source code. Runtime systems observe and characterize application behavior to drive resource management and allocation, including dep.ndence detection and parallelization, or scheduling. However, the source codes of target applications are not always available to the compiler or runtime system in an analyzable form. It becomes necessary to find alternate ways to model application behavior. This paper presents a novel mathematical framework to rebuild loops from their memory access traces. An exploration engine traverses a tree-like solution space, driven by the access strides in the trace. It is guaranteed that the engine will find the minimal affine nest capable of reproducing the observed sequence of accesses by exploring this space in a brute force fashion, but most real traces will not be tractable in this way. Methods for an efficient solution space traversal based on mathematical properties of the equation systems which model the solution space are proposed. The experimental evaluation shows that these strategies achieve efficient loop reconstruction, processing hundreds of gigabytes of trace data in minutes. The proposed approach is capable of correctly and minimally reconstructing 100% of the static control parts in PolyBench/C applications. As a side effect, the trace reconstruction process can be used to efficiently compress trace files. The proposed tool can also be used for dynamic access characterization, predicting over 99% of future memory accesses.

关键词： Indexes Optimization Engines Mathematical model Runtime Frequency modulation Space exploration

来源：评论

学校读者我要写书评

暂无评论

Nonlinear control of three-phase three-level four-wire NPC converter

Nonlinear control of three-phase three-level four-wire NPC c...

引用

IEEE International Conference on Industrial Technology (ICIT)

作者： A. Missanda K. Al-Haddad N. Mendalek Energy Conversion and Power Electronics CRC-ECPE École de Technologie Supérieure Montréal QC Canada Dep. of Electrical Computer & Communication Engineering Notre Dame University Zouk Mosbeh Lebanon

ISBN: (纸本)9781467380768

This paper presents a new approach of input-output feedback linearization control applied to the three-phase three-level four-wire neutral point clamped (NPC) converter. Under the proposed control strategy, the NPC converter demonstrates the capability to achieve simultaneously two tasks. The first task is to operate as a nonpolluting rectifier by regulating and nearly equalizing the two dc capacitor voltages while providing power to the dc loads. It is worthy of note that the voltage imbalance between the upper and lower capacitors and the neutral current represent a well-known problem in the three-level NPC converters. As a second task the NPC converter will behave as a shunt active power filter (SAPF) to compensate current harmonics, unbalances and reactive power produced by a combination of single-phase and three-phase nonlinear loads connected at the point of common coupling on the grid. The multivariable state space model of the NPC converter in the dq0 synchronous reference frame is used to design the nonlinear controller which is based on the input-output feedback linearization. It is shown that the model zero-dynamics is asymptotically stable ensuring the local stability of the internal dynamics. The proposed control strategy applied to the NPC converter is verified by computer simulations. The system stability is confirmed under severe dynamic changes in the operation conditions. The results of conducted simulations validate the viability and effectiveness of the NPC converter to maintain grid side currents balanced and near sinusoidal with unity displacement power factor. The simulation results also confirm the capability of the NPC converter to stabilize the dc voltages while supplying unbalanced dc loads.

关键词： Rectifiers Voltage control Load modeling Harmonic analysis Power harmonic filters Power system stability Capacitors

来源：评论

学校读者我要写书评

暂无评论

LDPC codes and iterative decoding over symbol-tuple error channels

LDPC codes and iterative decoding over symbol-tuple error ch...

引用

International Symposium on Turbo Codes and Related Topics

作者： Kenta Kasai Masanori Hirotomo Masakatu Morii Dep. of Communications and Computer Engineering Tokyo Institute of Technology Tokyo Japan Dept. of Information Science Saga University Saga Japan Dept. of Electrical and Electronic Engineering Kobe University Kobe Japan

This paper deals with symbol-pair error channels. First, we generalize the channels to symbol-tuple error channels whose read length is D. Then, we derive a message passing algorithm for decoding LDPC codes over the generalized channels. Furthermore, we investigate the Hamming distance distributions of LDPC codes in terms of D symbol-tuple metric.

关键词： Parity check codes Decoding Hamming weight Block codes Couplings Error analysis

来源：评论

学校读者我要写书评

暂无评论

Key management protocol with implicit certificates for IoT systems 1

Key management protocol with implicit certificates for IoT s...

引用

1st Workshop on IoT Challenges in Mobile and Industrial Systems, IoT-Sys 2015

作者： Sciancalepore, Savio Capossele, Angelo Piro, Giuseppe Boggia, Gennaro Bianchi, Giuseppe Politecnico di Bari Italy Dep. of Computer Science Sapienza University of Rome Italy Dep. of Electronic Engineering University of Rome 2 Tor Vergata Italy

ISBN: (纸本)9781450335027

This paper proposes a Key Management Protocol for mobile and industrial Internet of Things systems, targeting, at the same time, robust key negotiation, lightweight node authentication, fast re-keying, and efficient protection against replay attacks. The proposed approach pragmatically leverages widely accepted Elliptic Curve Cryptography constructions, specifically the (Elliptic Curve)"Fixed"Diffie Hellman key exchange and the (Elliptic Curve) Qu-Vanstone implicit certificates. Our value added is their suitable integration into a security protocol exchange, designed at layer 2, in the 802.15.4 protocol stack, which permits to i) avoid Elliptic Point multiplications upon rekeying of previously paired devices, and ii) support mutual authentication while securing the protocol exchange. To prove its viability, the proposed Key Management Protocol has been implemented and assessed on severely constrained devices. As expected, but made explicit and quantified by our experimental performance evaluation, the usage of implicit certificates in conjunction with an optimized message exchange yields impressive gains in terms of airtime consumption with respect to state of the art schemes. © 2015 ACM.

关键词： Internet of things

来源：评论

学校读者我要写书评

暂无评论

A coalitional game for femtocell clustering in OFDMA macro-femtocell networks

A coalitional game for femtocell clustering in OFDMA macro-f...

引用

NETWORKS International Telecommunications Network Strategy and Planning Symposium

作者： Katty Rohoden Rebeca Estrada Hadi Otrok Zbigniew Dziong Computer Science and Electronic Department UTPL Loja Ecuador Electrical Engineering Dep. Université du Québec Ecole de Technologie Supérieure Montréal QC Canada Electrical Engineering and Computer Science Faculty Escuela Superior Politécnica del Litoral ESPOL Guayaquil Ecuador

ISBN: (纸本)9781467389921

In this paper, we tackle the problem of resource management in macro-femtocell networks. Dense dep.oyment of femtocells imposes several challenges for a cluster-based resource allocation. Some of those challenges are the trade-off between the level of offloaded traffic from macrocell and bandwidth allocated to femto-tier, the fair distribution of resources, and the mitigation of inter-cluster interference. To overcome these limitations, we propose a coalitional game to form clusters of femtocells that can reduce the resource allocation complexity. Stable clusters are formed based on the core model. Our proposal mainly consists of three components. Namely, a femtocell selection for public users, a coalitional game where cooperative femtocells are rewarded, and a Weighted Water Filling algorithm to allocate resources. Our solution is performed under a rewarding model, which is based on an ideal spectral efficiency and on an effective spectral efficiency. We compare the results of our rewarding model with a non-cooperative model, where femtocells work in closed access mode. Simulation results demonstrate that our proposal improves the femto-tier throughput and the satisfaction of femtocells subscribers.

关键词： Resource management Games Ultrafast electronics Macrocell networks Bandwidth Interference Clustering algorithms

来源：评论

学校读者我要写书评

暂无评论

Model-based security analysis and applications to security economics 3

Model-based security analysis and applications to security e...

引用

3rd International Conference on Model-Driven engineering and Software Development, MODELSWARD 2015

作者： Jürjens, Jan Ahmadian, Amir Shayan Software Engineering Dep. of Computer Science TU Dortmund Dortmund Germany Fraunhofer Institute for Software and Systems Engineering ISST Dortmund Germany

ISBN: (纸本)9789897580833

In this invited presentation, we give an overview on a soundly based approach to Secure Software engineering based on the UML extension UMLsec. More specifically, one main current focus is the automated, formally based analysis of software artefacts against security requirements. This is motivated by the observation that the current state of security engineering in practice is far from satisfactory. The goal is thus to start with the actual industrial engineering methods of security-critical software-based systems, to identify problems which are practically amenable to tool-supported, formally sound analysis methods, and to try to solve these problems using these methods. An important objective is to ensure that these analysis methods can actually be used in practice by keeping the additional overhead in using them bounded: First, they take as input artefacts which are already available in current industrial software development (such as UML models and program source code) and do not have to be constructed just to perform the analysis. Second, the tools should be reasonably easy to use and have a strong emphasis on automation. We also present results from some recent work on applying model-based security analysis to the analysis of economic aspects of securing critical infrastructures. Copyright © 2015 SCITEPRESS - science and Technology Publications.

关键词： Security systems

来源：评论

学校读者我要写书评

暂无评论

Large Scale Assessment of Ka/Q Band Atmospheric Channel Across Europe with ALPHASAT TDP5: The Augmented Network

Large Scale Assessment of Ka/Q Band Atmospheric Channel Acro...

引用

European Conference on Antennas and Propagation

作者： S. Ventouras R. Reeves E. Rumi F. Perez-Fontan F. Machado V. Pastoriza A. Rocha S. Mota F. Jorge A.D. Panagopoulos A.Z. Papafragkakis C.I. Kourogiorgas O. Fiser V. Pek P. Pesice M. Grabner A. Vilhar A. Kelmendi A. Hrovat D. Vanhoenacker-Janvier A. Graziani L. Quibus G. Goussetis STFC Rutherford Appleton Laboratory RAL Space Oxford UK spiros Escola de Enxe?aría de Telecomunicación University of Vigo Vigo Spain Instituto de Telecomunica??es/Dep. Elect. Telec. e Informática IT/DETI Aveiro Portugal School of Electrical and Computer Engineering National Technical University of Athens Athens Greece Institute of Atmospheric Physics ASCR Meteorological Dept. IAP Prague Czech Republic Czech Metrology Institute TESTCOM CMI Prague Czech Republic Department of Communication Systems Jozef Stefan Institute Ljubljana Slovenia ICTEAM Université catholique de Louvain Louvain-la-Neuve Belgium School of Engineering and Physical Sciences Heriot-Watt University Edinburg UK

ISBN: (纸本)9781509037421

The upcoming migration of satellite services to higher bands, namely the Ka- and Q-bands offers many advantages in terms of bandwidth, data rates and system capacity. However, it poses challenges as propagation effects introduced by the various atmospheric phenomena are particularly pronounced in these bands and can become a serious constraint in terms of system reliability and performance. This paper outlines the goals, organization and some first results of an ongoing large propagation campaign consortium formed across Europe under the supervision of the European Space Agency;the campaign, shall ultimately assist in the validation and development of channel models targeting these-bands. Finally, the consideration of diverse climatic conditions and elevation angles along with the evaluation of the frequency and spatio-temporal effects, shall support the development of Fading and Mitigation Techniques and their assessment using real data.

关键词： Europe Atmospheric measurements Satellites Atmospheric modeling Satellite broadcasting Antennas Q measurement

来源：评论

学校读者我要写书评

暂无评论

Implementation of density functional theory method on object-oriented programming (C++) to calculate energy band structure using the projector augmented wave (PAW)

引用

Journal of Physics: Conference Series 2017年第1期853卷

作者： E Alfianto F Rusydi N D Aisyah R N Fadilla H K Dipojono M A Martoprawiro Dep. of Computer Systems Institut Teknologi Adhi Tama Surabaya Jl Arif Rachman Hakim 100 Surabaya Indonesia. Theoretical Physics Research Group Dep. of Physics Fac. of Science and Technology Universitas Airlangga Jl. Mulyorejo Surabaya Indonesia 60115 Laboratory of Computational Material Design Research Group of Engineering Physics Institut Teknologi Bandung Jl Ganesha 10 Bandung Indonesia 40132 Inorganic and Physical Chemistry Division Dep. of Chemistry Institut Teknologi Bandung Jl Ganesha 10 Bandung Indonesia 40132

This study implemented DFT method into the C++ programming language with object-oriented programming rules (expressive software). The use of expressive software results in getting a simple programming structure, which is similar to mathematical formula. This will facilitate the scientific community to develop the software. We validate our software by calculating the energy band structure of Silica, Carbon, and Germanium with FCC structure using the Projector Augmented Wave (PAW) method then compare the results to Quantum Espresso calculation's results. This study shows that the accuracy of the software is 85% compared to Quantum Espresso.

关键词：

来源：评论

学校读者我要写书评

暂无评论

Toward an Access Control Model for IOTCollab

引用

Procedia computer science 2015年 52卷 428-435页

作者： Mehdi Adda Jabril Abdelaziz Hamid Mcheick Rabeb Saad Mathematics Computer Science and Engineering Dep. University of Quebec at Rimouski Rimouski (Qc) Canada Mathematics and Computer Science Dep. University of Quebec at Chicoutimi Chicoutimi (Qc) Canada

The increase in Internet-connected physical devices offers new possibilities and opportunities. This Internet of Things (IoT) fosters the development of new platforms, services and applications that connect the physical world (represented by physical objects) to the virtual world (represented by the Internet). The work presented here proposes a study of role and attribute-based access control models that tackle the security concerns of our already developed data sharing framework. The framework introduced a formal theoretical model, the IOTCollab domain specific language, and an integrated development environment that implements this model. We have extended this framework by completing the formal theoretical model with access control capabilities.

关键词： IOTCollab Internet of Things Security Access Control

来源：评论

学校读者我要写书评

暂无评论

Extensions to the UML profile for MARTE for distributed embedded systems

Extensions to the UML profile for MARTE for distributed embe...

引用

Forum on Specification, Verification and Design Languages, FDL

作者： Emad Ebeid Julio Medina Davide Quaglia Franco Fummi Dep. of Engineering Aarhus University Denmark Dep. of Computer Science and Electronics University of Cantabria Spain Dep. of Computer Science University of Verona Italy

The design of distributed embedded systems is a challenging task that requires raising the level of abstraction to handle the different involved concerns. In particular, standard modeling languages and precise semantics specification are necessary to address the networking-related aspects at a high level of abstraction. The Unified Modeling Language (UML) and its MARTE profile are valid formalisms to model real-time embedded systems but they lack precise modeling elements when addressing applications and platforms forming distributed embedded systems. In this work, we formalize a coherent set of modeling elements for the design and dep.oyment of distributed embedded systems. A novel UML profile for networking is proposed as a semantic and syntactic extension to the UML Profile for MARTE: The Network Profile.

关键词： Unified modeling language Computational modeling Embedded systems Automata Delays Quality of service Mathematical model

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：