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Minimum-Time Aggregation Scheduling in Duty-Cycled Wireless Sensor Networks

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Journal of computer science & Technology 2011年第6期26卷 962-970页

作者：于博李建中 CCF School of computer science and Technology Harbin Institute of Technology

Aggregation is an important and commonplace operation in wireless sensor networks. Due to wireless interferences aggregation in wireless sensor networks often suffers from packet collisions. In order to solve the collision problem aggregation scheduling is extensively researched in recent years. In many sensor network applications such as real-time monitoring, aggregation time is the most concerned performance. This paper considers the minimum-time aggregation scheduling problem in duty-cycled wireless sensor networks for the first time. We show that this problem is NP-hard and present an approximation algorithm based on connected dominating set. The theoretical analysis shows that the proposed algorithm is a nearly-constant approximation. Simulation shows that the scheduling algorithm has a good performance.

关键词： aggregation duty-cycle scheduling sensor network

Distribution of populations in excited states of electrodeless discharge lamp of Rb atoms

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Chinese science Bulletin 2013年第16期58卷 1876-1881页

作者： TAO ZhiMing WANG YanFei HONG YeLong WANG DongYing ZHANG ShengNan ZHUANG Wei CHEN JingBiao State Key Laboratory of Advanced Optical Communication system and Network Institute of Quantum Electronics School of Electronics Engineering & Computer Science Peking University Department of Physics Bijie University

The intensity of fluorescence spectral lines of Rb atoms in the region of 350-1110nm is measured in eletrodeless discharge lamp. The population ratio between the excited states is calculated according to the spontaneous transition probabilities with rate equations. At the same time, the population density of energy level is also obtained. The results provide the potential applications of electrodeless discharge lamp in atomic filter and optical frequency reference at higher excited states without a pumping laser.

关键词：原子激发态无极灯铷原子种群分布人口密度无极放电灯原子滤光器概率计算

An effective fault prediction model developed using an extreme learning machine with various kernel methods

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Frontiers of Information Technology & Electronic Engineering 2018年第7期19卷 864-888页

作者： Lov KUMAR Anand TIRKEY Santanu-Ku.RATH Department of computer science and Engineering National Institute of Technology Rourkela

system analysts often use software fault prediction models to identify fault-prone modules during the design phase of the software development life cycle. The models help predict faulty modules based on the software metrics that are input to the models. In this study, we consider 20 types of metrics to develop a model using an extreme learning machine associated with various kernel methods. We evaluate the effectiveness of the mode using a proposed framework based on the cost and efficiency in the testing phases. The evaluation process is carried out by considering case studies for 30 object-oriented software systems. Experimental results demonstrate that the application of a fault prediction model is suitable for projects with the percentage of faulty classes below a certain threshold, which depends on the efficiency of fault identification(low: 47.28%; median: 39.24%; high: 25.72%). We consider nine feature selection techniques to remove the irrelevant metrics and to select the best set of source code metrics for fault prediction.

关键词： CK metrics Cost analysis Extreme learning machine Feature selection techniques Object-oriented software

A Survey on Graph Processing Accelerators:Challenges and Opportunities

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Journal of computer science & Technology 2019年第2期34卷 339-371页

作者： Chuang-Yi Gui Long Zheng Bingsheng He Cheng Liu Xin-Yu Chen Xiao-Fei Liao Hai Jin National Engineering Research Center for Big Data Technology and system School of Computer Science and Technology Huazhong University of Science and Technology Wuhan 430074 China Services Computing Technology and system Laboratory School of Computer Science and Technology Huazhong University of Science and Technology Wuhan 430074 China Cluster and Grid Computing Laboratory School of Computer Science and Technology Huazhong University of Science and Technology Wuhan 430074 China School of Computing National University of Singapore Singapore 117418 Singapore institute of Computing Technology Chinese Academy of Sciences Beijing 100190 China

Graph is a well known data structure to represent the associated relationships in a variety of applications,e.g.,data science and machine *** a wealth of existing efforts on developing graph processing systems for improving the performance and/or energy efficiency on traditional architectures,dedicated hardware solutions,also referred to as graph processing accelerators,are essential and emerging to provide the benefits significantly beyond what those pure software solutions can *** this paper,we conduct a systematical survey regarding the design and implementation of graph processing ***,we review the relevant techniques in three core components toward a graph processing accelerator:preprocessing,parallel graph computation,and runtime *** also examine the benchmarks and results in existing studies for evaluating a graph processing ***,we find that there is not an absolute winner for all three aspects in graph acceleration due to the diverse characteristics of graph processing and the complexity of hardware *** finally present and discuss several challenges in details,and further explore the opportunities for the future research.

关键词： graph processing accelerator domain-specific architecture performance energy efficiency

Learning dynamics of kernel-based deep neural networks in manifolds

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science China(Information sciences) 2021年第11期64卷 105-119页

作者： Wei WU Xiaoyuan JING Wencai DU Guoliang CHEN School of computer science Wuhan University institute of Deep-sea science and Engineering Chinese Academy of Sciences School of computer Guangdong University of Petrochemical Technology institute of Data science City University of Macau College of computer science and Software Engineering Shenzhen University

Convolutional neural networks(CNNs) obtain promising results via layered kernel convolution and pooling operations, yet the learning dynamics of the kernel remain obscure. We propose a continuous form to describe kernel-based convolutions through integration in neural manifolds. The status of spatial expression is proposed to analyze the stability of kernel-based CNNs. We divide CNN dynamics into the three stages of unstable vibration, collaborative adjusting, and stabilized fluctuation. According to the system control matrix of the kernel, the kernel-based CNN training proceeds via the unstable and stable status and is verified by numerical experiments.

关键词： learning dynamics kernel-based convolution manifolds control model network stability

Trudinger-Moser Type Inequality Under Lorentz-Sobolev Norms Constraint

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Journal of Partial Differential Equations 2021年第2期34卷 116-128页

作者： ZHU Maochun ZHENG Yifeng School of Mathematical sciences Institute of Applied System AnalysisJiangsu UniversityZhenjiang 212013China

In this paper,we are concerned with a sharp fractional Trudinger-Moser type inequality in bounded intervals of IR under the Lorentz-Sobolev norms *** any 1β***,when q is even,we obtain u∈Н1/2,2(I),^sup||(-△)1/4u||2,q≤1^(∫Ih(u)eβq|u(x)|q')dx≤+∞),for any function h:[0,∞→[0,∞)with lim t→∞h(t)=∞.As for the key tools of proof,we use Green functions for fractional Laplace operators and the rearrangement of a convolution to the rearrangement of the convoluted functions.

关键词： Trudinger-Moser inequality Lorentz-Sobolev space bounded intervals

Accurate and efficient exploit capture and classification

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science China(Information sciences) 2017年第5期60卷 193-209页

作者： Yu DING Tao WEI Hui XUE Yulong ZHANG Chao ZHANG Xinhui HAN institute of computer science and Technology Peking University Eletrical Engineering and computer sciences UC Berkeley

Software exploits, especially zero-day exploits, are major security threats. Every day, security experts discover and collect numerous exploits from honeypots, malware forensics, and underground ***, no easy methods exist to classify these exploits into meaningful categories and to accelerate diagnosis as well as detailed analysis. To address this need, we present Seismo Meter, which recognizes both control-flowhijacking, and data-only attacks by combining approximate control-flow integrity, fast dynamic taint analysis and API sandboxing schemes. Once it detects an exploit incident, Seismo Meter generates a succinct data representation, called an exploit skeleton, to characterize the captured exploit. Seismo Meter then classifies the captured exploits into different exploit families by performing distance computing on the extracted *** evaluate the efficiency of Seismo Meter, we conduct a field test using exploit samples from public exploit databases, such as Metasploit, as well as wild-captured exploits. Our experiments demonstrate that Seismo Meter is a practical system that successfully detects and correctly classifies all these exploit attacks.

关键词： software security exploit classification exploit attack capture control flow integrity JIT security

Cs 728 nm Laser Spectroscopy and Faraday Atomic Filter

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Chinese Physics Letters 2014年第12期31卷 27-30页

作者：刘忠征陶智明蒋招杰陈景标 State Key Laboratory of Advanced Optical Communication system and Network Institute of Quantum Electronics School of Electronics Engineering ~ Computer Science Peking University Beijing 100871 College of science Guizhou University of Engineering Science Bijie 551700

The laser spectroscopy of alkali-metal vapor is widely used in a number of applications, such as the Faraday anomalous dispersion optical fil- ter （FADOF）, the active optical clock, and wavelength ***＇ The Cs electrodeless dis- charge vapor lamp has rich spectra, including 455 nm, 459 nm, 728 nm, 852 nm, 1359 nm, and 1470 nm. The 852 nm laser pumping atoms from 6S1/2 to 6P3/2 have been used in *** 1359nm wave- length transited from 7S1/2 to 6P1/2 of Cs atoms can be used in the field of active optical clocks. The concept of active optical clocks has been proposed since 2005. Due to its good performance in sta- bility, the active optical clock has been extensively in- vestigated theoretically and experimentally in recent years, such as the two-level active optical clock, and three-level active optical clock. When considering the performance of the active optical clock, we hope to reduce the second-order Doppler shift in thermal atomic beam and the light shift induced by the pump- ing laser. To solve this issue, our group has recently proposed a four-level active optical clock, such as K 1252.2nm, Cs 1469nm, Rb 1366.9nm and Rb 728 nm. Moreover, the Rb 728 nm four-level quantum system has potentially a better performance than three long wavelength ones of Rb.

关键词： Laser Spectroscopy Faraday Atomic Filter electrodeless discharge

Reliable and Energy Efficient Protocol for Wireless Sensor Network

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Tsinghua science and Technology 2007年第S1期12卷 95-100页

作者：阚保强蔡理徐勇军 College of science Air Force Engineering University Key Laboratory of computer system and Architecture Institute of Computing TechnologyChinese Academy of Sciences

Low-power design is one of the most important issues in wireless sensor networks (WSNs) , while reliable information transmitting should be ensured as well. Transmitting power (TP) control is a simple method to make the power consumption down, but excessive interferences from potential adjacent operating links and communication reliability between nodes should be considered. In this paper, a reliable and energy efficient protocol is presented, which adopts adaptive rate control based on an optimal TP. A mathematical model considering average interference and network connectivity was used to predict the optimal TP. Then for the optimal TP, active nodes adaptively chose the data rate with the change of bit-error–rate(BER) performance. The efficiency of the new strategy was validated by mathematical analysis and simulations. Compared with 802.11 DCF which uses maximum unified TP and BASIC protocol, it is shown that the higher average throughput can achieve while the energy consumption per useful bit can be reduced according to the results.

关键词： wireless sensor networks reliable communication energy efficient optimal transmitting power adaptive link control