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Dynamic Mechanisms for Evolution of Mountain Rural Settlements and Soil Conservation in Upper Yangtze River Basin

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Wuhan University Journal of Natural Sciences 2007年第4期12卷 710-714页

作者： WANG Qing CHEN Yong School of Environment and Resource Southwest University of Science and Technology Mianyang 621010 Sichuan China Institute of Environment and Regional development Sichuan University Chengdu 610064 Sichuan China

This paper presents the logic relationship between rural settlement reconstruction and soil conservation in the Upper Yangtze River. Firstly, by introducing the concepts of ＂flow＂ and ＂intercepted flow＂, we probe into the dynamic mechanism on interaction between ecological and environmental system, and then point out that the ＂intercepting sites＂ are physical conditions for establishment of human settlements in mountains. Secondly, by using ecological theories, ＂flow＂, ＂source＂, and ＂sink＂, material cycle and energy flow in mountains have been discussed. Thirdly, according to dissipative structure theory and thermodynamic laws, a hypothesis has been proposed that ＂entropy flow＂ is a dynamic force for settlement evolution. Finally, it is argued that a project for soil conservation is set to control and utilize flows so rural settlements can be supported and farmers＇ life improved.

关键词： rural settlement entropy soil conservation project intercepted flow

Domain-specific modeling and verification for C4ISR capability requirements

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Journal of Central South University 2012年第5期19卷 1334-1340页

作者：董庆超王智学陈国友蒋鑫张婷婷 technology of Command and Control Department PLA University of Science and Technology Institute of Sciences PLA University of Science and Technology

An approach was proposed to specify the C4ISR capability of domain-specific modeling *** confine the domain modeling within a standard architecture framework,formally a C4ISR capability meta-ontology was defined according to the meta-model of DoD Architecture *** meta-ontology is used for extending UML Profile so that the domain experts can model the C4ISR domains using the C4ISR capability meta-concepts to define a domain-specific modeling *** domain models can be then checked to guarantee the consistency and completeness through converting the UML models into the Description logic ontology and making use of inference engine Pellet to verify the ontology.

关键词： C4ISR capability meta-ontology domain-specific modeling description logic

High-performance hardware architecture of elliptic curve cryptography processor over GF(2^(163))

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第2期10卷 301-310页

作者： Yong-ping DAN Xue-cheng ZOU Zheng-lin LIU Yu HAN Li-hua YI Department of Electronic Science and technology Huazhong University of Science and Technology Wuhan 430074 China

We propose a novel high-performance hardware architecture of processor for elliptic curve scalar multiplication based on the Lopez-Dahab algorithm over GF（2^163） in polynomial basis representation. The processor can do all the operations using an efficient modular arithmetic logic unit, which includes an addition unit, a square and a carefully designed multiplication unit. In the proposed architecture, multiplication, addition, and square can be performed in parallel by the decomposition of computation. The point addition and point doubling iteration operations can be performed in six multiplications by optimization and solution of data dependency. The implementation results based on Xilinx VirtexⅡ XC2V6000 FPGA show that the proposed design can do random elliptic curve scalar multiplication GF（2^163） in 34.11 μs, occupying 2821 registers and 13 376 LUTs.

关键词： Elliptic curve cryptography (ECC) Scalar multiplication Hardware implementation

High throughput N-modular redundancy for error correction design of memristive stateful logic

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Chinese Physics B 2023年第1期32卷 568-579页

作者：朱熙徐晖杨为平李智炜刘海军刘森王义楠龙泓昌 College of Electronic Science and technology National University of Defense TechnologyChangsha 410073China

Memristive stateful logic is one of the most promising candidates to implement an in-memory computing system that computes within the storage *** can eliminate the costs for the data movement in the traditional von Neumann ***,the instability in the memristors is inevitable due to the limitation of the current fabrication technology,which incurs a great challenge for the reliability of the memristive stateful *** this paper,the implication of device instability on the reliability of the logic event is *** mathematical relationship between logic reliability and redundancy has been *** combining the mathematical relationship with the vector-matrix multiplication in a memristive crossbar array,the logic error correction scheme with high throughput has been ***,a universal design paradigm has been put forward for complex *** the circuit schematic and the flow of the scheme have been ***,a 1-bit full adder(FA)based on the NOR logic and NOT logic is simulated and the mathematical evaluation is *** demonstrates the scheme can improve the reliability of the logic *** compared with other four error corrections,the scheme which can be suitable for all kinds of R–R logics and V–R logics has the best universality and *** with the other two approaches which also need additional complementary metal–oxide semiconductor(CMOS)circuits,it needs fewer transistors and cycles for the error correction.

关键词： memristor stateful logic logic reliability in-memory computing

EDOA: an efficient delay optimization approach for mixed-polarity Reed-Muller logic circuits under the unit delay model

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Frontiers of Computer Science 2019年第5期13卷 1102-1115页

作者： Zhenxue HE Limin XIAO Fei GU Li RUAN Zhisheng HUO Mingzhe LI Mingfa ZHU Longbing ZHANG Rui LIU Xiang WANG College of Information Science and technology Hebei Agricultural University Baoding 071001 China State Key Laboratory of Software development Environment Beihang University Beijing 100083 China School of Computer Science and Engineering Beihang University Beijing 100083 China School of Electronic and Information Engineering Beihang University Beijing 100083 China State Key Laboratory of Computer Architecture Institute of Computing Technology Chinese Academy of Sciences Beijing 100190 China National Engineering Research Center for Science & technology Resources Sharing Service Beijing 100083 China

Delay optimization has recently attracted signif-icant attention. However, few studies have focused on the delay optimization of mixed-polarity Reed-Muller (MPRM) logic circuits. In this paper, we propose an efficient delay op-timization approach (EDOA) for MPRM logic circuits under the unit delay model, which can derive an optimal MPRM logic circuit with minimum delay. First, the simplest MPRM expression with the fewest number of product terms is ob-tained using a novel Reed-Muller expression simplification approach (RMESA) considering don't-care terms. Second, a minimum delay decomposition approach based on a Huffman tree construction algorithm is utilized on the simplest MPRM expression. Experimental results on MCNC benchmark cir-cuits demonstrate that compared to the Berkeley SIS 1.2 and ABC, the EDOA can significantly reduce delay for most cir-cuits. Furthermore, for a few circuits, while reducing delay, the EDOA incurs an area penalty.

关键词： delay optimization mixed-polarity Reed-Muller logic circuits unit delay model don't-care terms,

A Shape Graph logic and A Shape System

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Journal of Computer Science & technology 2013年第6期28卷 1063-1084页

作者：李兆鹏张昱陈意云 CCF School of Computer Science and technology University of Science and Technology of China Software Security Laboratory Suzhou Institute for Advanced StudyUniversity of Science and Technology of China

Analysis and verification of pointer programs are still difficult problems so far. This paper uses a shape graph logic and a shape system to solve these problems in two stages. First, shape graphs at every program point are constructed using an analysis tool. Then, they are used to support the verification of other properties （e.g., orderedness）. Our prototype supports automatic verification of programs manipulating complex data structures such as splay trees, treaps, AVL trees and AA trees, etc. The proposed shape graph logic, as an extension to Hoare logic, uses shape graphs directly as assertions. It can be used in the analysis and verification of programs manipulating mutable data structures. The benefit using shape graphs as assertions is that it is convenient for acquiring the relations between pointers in the verification stage. The proposed shape system requires programmers to provide lightweight shape declarations in recursive structure type declarations. It can help rule out programs that construct shapes deviating from what programmers expect （reflected in shape declarations） in the analysis stage. As a benefit, programmers need not provide specifications （e.g., pre-/post-conditions, loop invariants） about pointers. Moreover, we present a method doing verification in the second stage using traditional Hoare logic rules directly by eliminating aliasing with the aid of shape graphs. Thus, verification conditions could be discharged by general theorem provers.

关键词： shape graph logic program verification shape analysis automated theorem proving loop invariant inference

Nonmonotonic propositional logic

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Frontiers of Computer Science 2021年第3期15卷 215-216页

作者： Wei LI Yuefei SUI Yuhui WANG State Key Laboratory of Software development Environment Beihang UniversityBeijing 100191China Key Laboratory of Intelligent Information Processing Institute of Computing TechnologyChinese Academy of SciencesBeijing 100190China School of Computer and Control Engineering University of Chinese Academy of SciencesBeijing 100049China Information technology Center China Reinsurance(Group)CorporationBeijing 100033China

Propositional logic[1]is basic,based on which other logics are *** deduction system for propositional logic is *** logics are a class of logics which deduction systems are *** ones are default logic[2,3],R-calculus[4]... 详细信息

关键词： default propositional Nonmonotonic

An efficient and fast polarity optimization approach for mixed polarity Reed-Muller logic circuits

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Frontiers of Computer Science 2017年第4期11卷 728-742页

作者： Zhenxue HE Limin XIAO Fei GU Tongsheng XIA Shubin SU Zhisheng HUO Rong ZHANG Longbing ZHANG Li RUAN Xiang WANG State Key Laboratory of Software development Environment Beihang University Beijing 100191 China School of Computer Science and Engineering Beihang University Beijing 100191 China School of Electronic and Information Engineering Beihang University Beijing 100191 China State Key Laboratory of Computer Architecture Institute of Computing Technology Chinese Academy of Sciences Beijing 100190 China National Engineering Research Center for Science & technology Resources Sharing Service Beijing 100191 China

Although the genetic algorithm has been widely used in the polarity optimization of mixed polarity Reed- Muller （MPRM） logic circuits, few studies have taken into account the polarity conversion sequence. In order to im- prove the efficiency of polarity optimization of MPRM logic circuits, we propose an efficient and fast polarity optimiza- tion approach （FPOA） considering the polarity conversion se- quence. The main idea behind the FPOA is that, firstly, the best polarity conversion sequence of the polarity set wait- ing for evaluation is obtained by using the proposed hybrid genetic algorithm （HGA）; secondly, each of polarity in the polarity set is converted according to the best polarity con- version sequence obtained by HGA. Our proposed FPOA is implemented in C and a comparative analysis has been pre- sented for MCNC benchmark circuits. The experimental re- suits show that for the circuits with more variables, the FPOA is highly effective in improving the efficiency of polarity op- timization of MPRM logic circuits compared with the tradi- tional polarity optimization approach which neglects the po- larity conversion sequence and the improved polarity opti- mization approach with heuristic technique.

关键词： genetic algorithm polarity optimization mixed

Numerical analysis of motional mode coupling of sympathetically cooled two-ion crystals

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Chinese Physics B 2021年第7期30卷 234-243页

作者： Li-Jun Du Yan-Song Meng Yu-Ling He Jun Xie China Academy of Space technology(Xi'an) Xi'an 710100China National Key Laboratory of Science and technology on Space Microwave China Academy of Space Technology(Xi'an)Xi'an 710100China China Academy of Space technology Beijing 100094China

A two-ion pair in a linear Paul trap is extensively used in the research of the simplest quantum-logic system;however,there are few quantitative and comprehensive studies on the motional mode coupling of two-ion systems *** study proposes a method to investigate the motional mode coupling of sympathetically cooled two-ion crystals by quantifying three-dimensional(3 D)secular spectra of trapped ions using molecular dynamics *** 3 D resonance peaks of the^(40)Ca^(+)–^(27)Al^(+)pair obtained by using this method were in good agreement with the 3 D in-and out-of-phase modes predicted by the mode coupling theory for two ions in equilibrium and the frequency matching errors were lower than 2%.The obtained and predicted amplitudes of these modes were also qualitatively *** was observed that the strength of the sympathetic interaction of the^(40)Ca^(+)–^(27)Al^(+)pair was primarily determined by its axial in-phase *** addition,the frequencies and amplitudes of the ion pair's resonance modes(in all dimensions)were sensitive to the relative masses of the ion pair,and a decrease in the mass mismatch enhanced the sympathetic cooling *** sympathetic interactions of the^(40)Ca^(+)–^(27)Al^(+)pair were slightly weaker than those of the^(24)Mg^(+)–^(27)Al^(+)pair,but significantly stronger than those of^(9)Be^(+)–^(27)Al^(+).However,the Doppler cooling limit temperature of^(40)Ca^(+)is comparable to that of^(9)Be^(+)but lower than approximately half of that of^(24)Mg^(+).Furthermore,laser cooling systems for^(40)Ca^(+)are more reliable than those for^(24)Mg^(+)and^(9)Be^(+).Therefore,^(40)Ca^(+)is probably the best laser-cooled ion for sympathetic cooling and quantum-logic operations of^(27)Al^(+)and has particularly more notable comprehensive advantages in the development of high reliability,compact,and transportable^(27)Al^(+)optical *** methodology may be extended to multi-ion systems,and it will greatly aid efforts to control the dy

关键词： sympathetic cooling coupled oscillations secular motion radio-frequency ion traps