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Experimental measurement of growth patterns on fossil corals:Secular variation in ancient Earth-Sun distances

Chinese Science Bulletin 2010年第35期55卷 4010-4017页

作者： ZHANG WeiJia1,3,4,LI ZhengBin2,3 & LEI Yang1 1 Department of Physics,Peking University,Beijing 100871,China 2 Department of Electrical engineering and computer Science,Peking University,Beijing 100871,China 3 State Key laboratory of advanced Optical Communication systems & Networks,Peking University,Beijing 100871,China 4 Committee of Yuanpei Honors Program,Peking University,Beijing 100871,China Department of Physics Peking University Beijing 100871 China State Key Laboratory of Advanced Optical Communication Systems & Networks Peking University Beijing 100871 China Committee of Yuanpei Honors Program Peking University Beijing 100871 China Department of Electrical Engineering and Computer Science Peking University Beijing 100871 China

In recent years,much attention has been given to the increase in the Earth-Sun distance,with the modern rate reported as 5-15 m/cy on the basis of astronomical ***,traditional methods cannot measure the ancient leaving rates,so a myriad of research attempting to provide explanations were met with unmatched *** this paper we consider that the growth patterns on fossils could reflect the ancient Earth-Sun *** mechanical analysis of both the Earth-Sun and Earth-Moon systems,these patterns confirmed an increase in the Earth-Sun *** a large number of well-preserved specimens and new technology available,both the modern and ancient leaving rates could be measured with high precision,and it was found that the Earth has been leaving the Sun over the past 0.53 billion *** Earth's semi-major axis was 146 million kilometers at the beginning of the Phanerozoic Eon,equating to 97.6% of its current *** modern leaving rates are 5-14 m/cy,whereas the ancient rates were much *** results indicate a special expansion with an average expansion coefficient of 0.57H0 and deceleration in the form of Hubble *** the basis of experimental results,the Earth's semi-major axis could be represented by a simple formula that matches fossil measurements.

关键词：地球太阳古代距离生长模式实验石珊瑚量化

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One Day Smart Grid Supersession - Analytics and Integration

One Day Smart Grid Supersession - Analytics and Integration

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IEEE Power and Energy Society General Meeting

作者： W. H. Edwin Liu Stephen McArthur Jay Giri Karen Miu Rob Pratt Jun Wen Bob Uluski Luther Dow Gerard Labut Pacific Gas & Electric Company USA Bechtel Institute for Energy and Environment British Energy Advanced Diagnostics Centre University of Strathclyde UK Power Systems Technology and Strategic Initiatives ALSTOM Grid Redmond WA USA Electrical and Computer Engineering Department Drexel University USA Smart Grid Research and Development Pacific Northwest National Laboratory's (PNNL's) USA Transmission and Interconnection Planning Group Southern California Edison (SCE) Company USA EPRI's Power USA West Coast Operations Quanta Technology USA SmartCurrentssm Program Strategy DTE Energy Detroit MI USA

ISBN: (纸本)9781457710001

The effort of "Smart Grid" is to modernize grid infrastructure and build-in intelligence to power grids and delivery systems, and their interfaces to customer premises. However, the perspectives range from an emphasis on infrastructure to an emphasis on new paradigm-shifting applications. Alternatively, the smart grid can be thought of as the advanced information technologies that enable the desired analytical applications. As a general understanding, we believe that Smart Grid needs to integrate power system analysis, computing and economics to enhance grid reliability, efficiency, and security, and contributes to the climate change strategic goal. In this Supersession, the analytics that empowers smart grid applications is discussed;and the practical implementation and integration challenges will be presented.

关键词： Smart grid Analytical applications System integration Smart grids systems Integration Power system analysis computing information technology DNA Integration integration INFRASTRUCTURE

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Passive scheme with a photon-number-resolving detector for monitoring the untrusted source in a plug-and-play quantum-key-distribution system

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Physical Review A 2010年第4期82卷 042301-042301页

作者： Bingjie Xu Xiang Peng Hong Guo State Key Laboratory of Advanced Optical Communication Systems and Networks (Peking University) School of Electronics Engineering and Computer Science Peking University Beijing 100871 China

A passive scheme with a beam splitter and a photon-number-resolving (PNR) detector is proposed to verify the photon statistics of an untrusted source in a plug-and-play quantum-key-distribution system by applying a three-intensity decoy-state protocol. The practical issues due to statistical fluctuation and detection noise are analyzed. The simulation results show that the scheme can work efficiently when the total number of optical pulses sent from Alice to Bob is above 108, and the dark count rate of the PNR detector is below 0.5 counts/pulse, which is realizable with current techniques. Furthermore, we propose a practical realization of the PNR detector with a variable optical attenuator combined with a threshold detector.

关键词： Photons

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Multi-Objective Virtual Machine Placement in Virtualized Data Center Environments

Multi-Objective Virtual Machine Placement in Virtualized Dat...

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IEEE/ACM Int'l Conference on & Int'l Conference on Cyber, Physical and Social Computing (CPSCom) Green Computing and Communications (GreenCom)

作者： Jing Xu Jose A. B. Fortes Advanced Computing and Information Systems Laboratory Department of Electrical and Computer Engineering University of Florida Gainesville FL USA

Server consolidation using virtualization technology has become increasingly important for improving data center efficiency. It enables one physical server to host multiple independent virtual machines (VMs), and the transparent movement of workloads from one server to another. Fine-grained virtual machine resource allocation and reallocation are possible in order to meet the performance targets of applications running on virtual machines. On the other hand, these capabilities create demands on system management, especially for large-scale data centers. In this paper, a two-level control system is proposed to manage the mappings of workloads to VMs and VMs to physical resources. The focus is on the VM placement problem which is posed as a multi-objective optimization problem of simultaneously minimizing total resource wastage, power consumption and thermal dissipation costs. An improved genetic algorithm with fuzzy multi-objective evaluation is proposed for efficiently searching the large solution space and conveniently combining possibly conflicting objectives. The simulation-based evaluation using power-consumption and thermal-dissipation models based on profiling of a Blade Center, demonstrates the good performance, scalability and robustness of our proposed approach. Compared with four well-known bin-packing algorithms and two single-objective approaches, the solutions obtained from our approach seek good balance among the conflicting objectives while others cannot.

关键词： Servers Optimization Power demand Virtual machining Resource management Memory management Thermal management

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On the Use of Machine Learning to Predict the Time and Resources Consumed by Applications 10

On the Use of Machine Learning to Predict the Time and Resou...

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IEEE/ACM International Symposium on Cluster Computing and the Grid (CCGRID)

作者： Andréa Matsunaga José A.B. Fortes Advanced Computing and Information Systems Laboratory Department of Electrical and Computer Engineering University of Florida Gainesville FL USA

ISBN: (纸本)9780769540399

Most data centers, clouds and grids consist of multiple generations of computing systems, each with different performance profiles, posing a challenge to job schedulers in achieving the best usage of the infrastructure. A useful piece of information for scheduling jobs, typically not available, is the extent to which applications will use available resources once they are executed. This paper comparatively assesses the suitability of several machine learning techniques for predicting spatio temporal utilization of resources by applications. Modern machine learning techniques able to handle large number of attributes are used, taking into account application- and system-specific attributes (e.g., CPU micro architecture, size and speed of memory and storage, input data characteristics and input parameters). The work also extends an existing classification tree algorithm, called Predicting Query Runtime (PQR), to the regression problem by allowing the leaves of the tree to select the best regression method for each collection of data on leaves. The new method (PQR2) yields the best average percentage error, predicting execution time, memory and disk consumption for two bioinformatics applications, BLAST and RAxML, deployed on scenarios that differ in system and usage. In specific scenarios where usage is a non-linear function of system and application attributes, certain configurations of two other machine learning algorithms, Support Vector Machine and k-nearest neighbors, also yield competitive results. In addition, experiments show that the inclusion of system performance and application-specific attributes also improves the performance of machine learning algorithms investigated.

关键词： Machine learning Machine learning algorithms Processor scheduling Regression tree analysis Mesh generation Cloud computing Grid computing Classification tree analysis Classification algorithms Prediction algorithms

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Data transmission model based on multi-channel unidirectional ring network

Data transmission model based on multi-channel unidirectiona...

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2010 International Conference on computer Application and System Modeling, ICCASM 2010

作者： Meng, Baoguo Zhang, Zhenrong Peng, Shuping Zhong, Yucheng Li, Zhengbin He, Yongqi Zhu, Lixin Xu, Anshi Zhang, Yanmei State Key Laboratory of Advanced Optical Communication Systems and Networks Peking University Beijing 100871 China School of Information Engineering China University of Geosciences Beijing 100083 China School of Computer Electronics and Information Guangxi University Nanning 530004 China

ISBN: (纸本)9781424472369

Based on a multi-channel unidirectional ring network test bed, a data transmission model is established and tested. The settings and the implementation of the model are introduced in detail. Finally, the model is tested based on the test bed. The results from both the sending and the receiving transmission platforms show the data transmission model can work effectively. © 2010 IEEE.

关键词： Data transfer

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Studying the impact of synchronization frequency on scheduling tasks with dependencies in heterogeneous systems

Studying the impact of synchronization frequency on scheduli...

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作者： Andronikos, Theodore Ciorba, Florina M. Riakiotakis, Ioannis Papakonstantinou, George Chronopoulos, Anthony T. Department of Informatics Ionian University Corfu Greece Computing Systems Laboratory Department of Electrical and Computer Engineering National Technical University of Athens Greece Center for Advanced Vehicular Systems Mississippi State University MS United States Department of Computer Science University of Texas at San Antonio 6900 N. Loop 1604 West San Antonio TX 78249 United States

In this work, we develop and evaluate a theoretical model, which we then use to study the impact of the synchronization frequency on the performance of dynamic self-scheduling algorithms. These algorithms are used to parallelize loops with data dependencies on heterogeneous systems. The proposed model uses a formula to estimate the parallel time as a function of the synchronization frequency. Inter-node communication has been proven to be the dominant factor for the performance degradation of applications containing loops with data dependencies. The synchronization mechanism therefore requires careful fine-tuning in order to give the best possible performance. The proposed model determines the optimal synchronization frequency that results in the minimum parallel time. We use this model to study the impact of the synchronization frequency on the parallel execution of a computational kernel from image processing. For this kernel, the synchronization frequency giving the minimum parallel time predicted by our theoretical model was very close to the synchronization frequency giving the least parallel time in practice. We validate our model by extensive comparisons of the theoretically predicted parallel time and synchronization frequency against those obtained from practical experiments. The comparisons show that the proposed model is highly accurate, its predictions for the optimal synchronization frequency being within 0.0250% of the experimentally optimal synchronization frequency in the best case, and within 0.1750% of the experimentally optimal synchronization frequency in the worst case. Finally, the comparisons show that the proposed model improves on a previously existing model in heterogeneous systems, whereas it gives similar results in homogeneous systems. © 2010 Elsevier B.V. All rights reserved.

关键词： Synchronization

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Performance evaluation of MB-OFDM ultra-wideband over fiber transmission using a low cost electro-absorption modulator integrated laser

Performance evaluation of MB-OFDM ultra-wideband over fiber ...

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2010 IEEE International Topical Meeting on Microwave Photonics, MWP 2010

作者： Sui, Chengwen Hraimel, Bouchaib Zhang, Xiupu Wu, Ke Liu, Taijun Xu, Tiefeng Nie, Qiuhua Advanced Photonic Systems Laboratory Department of Electrical and Computer Engineering Concordia University Montreal QC H3G1M8 Canada Polygrames Research Center Ecole Polytechnique de Montreal Montreal QC Canada College of Information Science and Engineering Ningbo University Zhejiang 315211 China

ISBN: (纸本)9781424478255

The performance of Multiband-Orthogonal Frequency Division Multiplexing (MB-OFDM) Ultra-WideBand (UWB) signal over single mode fiber system using a low cost Electro-Absorption Modulator (EAM) integrated laser (EML) is studied experimentally. Error Vector Magnitude (EVM) measurement is carried out to evaluate the system performance considering the effect of bias voltage, bias current temperature and optical modulation index of the EML, and fiber length. The experiment results showed that by using an EML, the UWB signal transmission over fiber can be cost effectively implemented. ©2010 IEEE.

关键词： Single mode fibers

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A goal-oriented fuzzy reactive control for mobile robots with automatic rule optimization

A goal-oriented fuzzy reactive control for mobile robots wit...

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2010 IEEE/RSJ International Conference on Intelligent Robots and systems

作者： Anmin Zhu Simon X. Yang School of Computer Science and Software Engineering Shenzhen University China Advanced Robotics and Intelligent Systems ARIS) Laboratory School of Engineering University of Guelph Canada

To realize real-time goal-oriented navigation for a mobile robot in unpredictable environments, a fuzzy reactive system is proposed in this paper. Besides the establishment of the fuzzy logic system, this paper focuses on the the physical meaning of the parameters in the fuzzy system, and proposes a systematic method to automatically suppress redundant fuzzy rules from the rule base. Under the control of the proposed system with automatic redundant fuzzy rule removal, the mobile robot can preferably avoid obstacles autonomously, and generate reasonable trajectories toward the target in various situations. The effectiveness and efficiency of the proposed approach are demonstrated by simulation and experimental studies.

关键词： Mobile robots Robot sensing systems Wheels Fuzzy logic Navigation

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Astronomy and Cosmology

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IEEE SIGNAL PROCESSING MAGAZINE 2010年第1期27卷 13-+页

作者： Leshem, Amir Kamalabadi, Farzad Kuruoglu, Ercan Engin van der Veen, Alle-Jan Center for Engineering Systems Advanced Research Computer Science and Mathematics Division Oak Ridge National Laboratory Oak Ridge TN USA

This special issue is devoted to advanced signal processing techniques used in astronomy and cosmology that enable progress in solving the major problems in observational *** first part of this special issue deals with digital interferometry in the radio and optical domains, while the second part deals with applications of signal processing to cosmology.

关键词： Astronomy Uniform resource locators Biomedical signal processing Acoustic signal processing Dark energy Signal processing algorithms Optical signal processing Optical interferometry Array signal processing Frequency

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