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A new construction method of LDPC codes for optical transmission systems

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Frontiers of Optoelectronics 2012年第3期5卷 311-316页

作者： Jianguo YUAN Yuexing JIA Wenjuan BI Liang XU Key Laboratory of Optical Fiber Communications Technology Chongqing University of Posts and Telecommunications Chongqing 400065 China

Based on the construction method of system- atically constructed Gallager （SCG）（4, k） code, a new improved construction method of low density parity check （LDPC） code is proposed. Compared with the construction method of SCG（4, k） codes improved before, the proposed construction method has some advantages, such as saving storage space and reducing computation complexity in the hardware implementation. And then LDPC（5929, 5624） code with 5.42% redundancy is constructed by the proposed method. The simulation results and analysis show that the constructed LDPC（5929, 5624） code has better error-correction performance, lower redundancy and lower decoding complexity than those of a classic Reed- Solomon （RS）（255, 239） code. Therefore, LDPC（5929, 5624） code, constructed by the proposed construction method on LDPC codes, can better suitable for optical transmission systems.

关键词： low density parity check (LDPC) codes netcoding gain (NCG) construction method optical transmis-sion systems

construction method of Modern Architecture under the Background of the Times

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Journal of Landscape Research 2021年第5期13卷 15-17,24页

作者： WANG Xiaojian YAN Yuewen School of Architecture and Art Hebei University of EngineeringHandanHebei 056038China Handan Key Laboratory of Architectural Physics and Regional Building Protection Technology HandanHebei 056038China

Taking the development of the times as the background,the historical evolution of modern architecture is combed from the perspective of the initial stage of industrialization to post-industrialization and then to the information *** can be seen that there is a close connection between development and modern architecture in the context of the *** the advancement of science and technology,the construction of buildings has undergone varying degrees of changes due to aesthetics,materials,structure,humanities,and *** these changes are the results of the progress and development of social *** changing people’s social cognition,it also changes the development process of architecture.

关键词： Time background Modern architecture construction method

construction method for Performance Management Curriculum Content System Based on Knowledge Graph

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教育研究前沿（中英文版） 2024年第3期14卷 8-12页

作者： Miaomiao Ma Xia Mu Chongqing Institute of Engineering Chongqing400040China

Performance Management is the core course of human resource management major,but its knowledge points lack multi-dimensional *** are problems such as scattered content and unclear system,and it is urgent to reconstruct the content system of the *** graph technology can integrate massive and scattered information into an organic structure through semantic correlation and *** application of knowledge graph to education and teaching can promote scientific and personalized teaching evaluation and better realize individualized *** paper systematically combs the knowledge points of Performance Management course and forms a comprehensive knowledge *** knowledge point is associated with specific questions to form the problem map of the course,and then the knowledge point is further associated with the ability target to form the ability map of the ***,the knowledge point is associated with teaching materials,question bank and expansion resources to form a systematic teaching database,thereby giving the method of building the content system of Performance Management course based on the knowledge *** research can be further extended to other core management courses to realize the deep integration of knowledge graph and teaching.

关键词： Knowledge Graph construction method Curriculum Content System Performance Management Course

Comparison of construction method for DEM Simulation of Ellipsoidal Particles

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Chinese Journal of Chemical Engineering 2013年第7期21卷 800-807页

作者：陶贺钟文琪金保升 School of Civil construction Zhengzhou Institute of Aeronautical Industry Management Zhengzhou 450000 China School of Energy & Environment -Southeast University Nanjing 210096 China

Discrete element model was developed to simulate the ellipsoidal particles moving in the moving bed. Multi-element model was used to describe a ellipsoidal particle, the contact detection algorithm of ellipsoidal particle was developed, and both contact force and gravity force were considered in the models. The simulation results were validated by our experiment. Three algorithms for representing an ellipsoidal particle were compared in macro and micro aspects. The results show that there exists big difference in the microscopic parameters such as kinetic energy, rotational kinetic energy, deformation, contact force and collision number which leads to the difference of macroscopic parameters. The relative error in the discharge rate and tracer particle position is the largest between 3-tangent-element representation and experimental results. The flow pattern is similar for the 5-element and 3-intersection representations. The only difference is the discharge rate of 5-element representation is larger than the experimental value and that of the 3-intersection representation has the contrary result. Finally the 3-intersection- element reoresentation is chosen in the simulation due to less comouting time than that of the 5-element renresentation.

关键词： ellipsoidal particle multi-element model moving bed discrete element model construction method

Constructing the three-qudit unextendible product bases with strong nonlocality

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Chinese Physics B 2022年第6期31卷 170-182页

作者： Bichen Che Zhao Dou Xiubo Chen Yu Yang Jian Li Yixian Yang Information Security Center State Key Laboratory of Networking and Switching TechnologyBeijing University of Posts and TelecommunicationsBeijing 100876China Information Security Center Beijing University of Posts and TelecommunicationsBeijing 100876China

Unextendible product bases(UPBs)are interesting members of a family of orthogonal product ***,we investigate the construction of 3-qudit UPBs with strong ***,a UPB set in C^(3)■C^(3)■C^(3)of size 19 is presented based on the shift *** mapping the system to a Rubik’s cube,we provide a general method of constructing UPBs in C^(d)■C^(d)■C^(d)of size(d-1)^(3)+2d+5,whose corresponding Rubik’s cube is composed of four ***,for the more general case where the dimensions of parties are different,we extend the classical tile structure to the 3-qudit system and propose the tri-tile *** means of this structure,a C^(4)■C^(4)■C^(5)system of size 38 is obtained based on a C^(3)■C^(3)■C^(4)system of size ***,we generalize this approach to the C^(d1)■C^(d2)■C^(d3)system which also consists of four *** research provides a positive answer to the open question raised in by Halder et al.[***.122040403(2019)],indicating that there do exist UPBs that can exhibit strong quantum nonlocality without entanglement.

关键词： strong nonlocality unextendible product bases tri-tile structure construction method

Local structure-preserving algorithms for partial differential equations

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Science China Mathematics 2008年第11期51卷 2115-2136页

作者： WANG YuShun WANG Bin QIN MengZhao School of Mathematics and Computer Science Nanjing Normal UniversityNanjing 210097China LASG Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China Institute of Computational Mathematics Chinese Academy of SciencesBeijing 100871China

In this paper, we discuss the concept of local structure-preserving algorithms (SPAs) for partial differential equations, which are the natural generalization of the corresponding global SPAs. Local SPAs for the problems with proper boundary conditions are global SPAs, but the inverse is not necessarily valid. The concept of the local SPAs can explain the difference between different SPAs and provide a basic theory for analyzing and constructing high performance SPAs. Furthermore, it enlarges the applicable scopes of SPAs. We also discuss the application and the construction of local SPAs and derive several new SPAs for the nonlinear Klein-Gordon equation.

关键词： SPAs local conservation law construction method discrete Leibnitz rule 65L06 65M06 65M12

Model Test for Dynamic construction Mechanical Effect of Large-Span Loess Tunnel

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Journal of Shanghai Jiaotong university(Science) 2011年第1期16卷 112-117页

作者：何本国朱永全叶朝良张志强 School of Civil Engineering Southwest Jiaotong University School of Civil Engineering Shijiazhuang Tiedao University

It has been a focus of debate for a large time on construction methods for large-span loess *** construction method has much effect on stability of tunnel and construction *** and failure of surrounding rock are quite *** with the large-span loess tunnel of Zhengzhou- Xi'an high-speed passenger rail line in China,large scale model test with geometric proportion 1:20 is applied to study on dynamic mechanical behavior of various construction *** include full-face excavation with support and no support,and benching method with *** is found that pre-deformation and stress accumulation take place ahead of working *** effects of three construction methods are further studied,particularly in terms of tunnel displacement and stress *** is revealed that benching method transfers load to an unexcavated area,limits horizontal deformation,reduces stress concentration effectively,lengthens the distance between location of peak for stress concentration and working face,and consequently increases *** model test results not only supply theoretical foundation for determination of reasonable construction method,but also can act as reference for similar tunnel and underground engineering construction.

关键词： physical model construction method loess tunnel construction mechanics stability

construction and control technology of the main bridge superstructure of Sutong Bridge

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Engineering Sciences 2009年第1期7卷 76-82页

作者： Zhang Hong Luo Chenbin Zhang Yongtao You Xinpeng Huazhong University of Science and Technology Wuhan 430074 China CCCC-Second Harbour Engineering Company Limited Wuhan 430014 China

The Sutong Yangtze River Bridge(short as Sutong Bridge)is now the largest span cable-stayed bridge in the *** construction of the superstructure of the middle bridge covered several stages including erection of the big block girders for the side span,assistant span and tower area,erection of standard girders and closure of the middle *** big block girders were hoisted by a floating crane,and the standard girders were hoisted by a double crane system on the *** pushing assistant method was adopted for the middle span closure ***,key technologies and innovative methods used in the processes of girder erection and cable assemblage in all stages were expatiated *** all-stage self-adaptive geometry control method was used in the construction *** accurately controlling the unstressed dimensions and shape of all structural components in each step,and realization that the control system and the controlled system adapt to each other,the goal was to make control of the final line shape and inner force of the bridge structure *** solutions,including GPS based and total station based dynamic geometry monitoring systems,were used to resolve the measure problem under the wide-range of wind-induced vibrations in the long cantilever ***,research on the wind-induced vibration of the superstructure during the construction period was *** response analysis to the longest single and double cantilever states were carried *** analysis and evaluation of wind resistance safety of the main girders under the longest single cantilever state was made,and corresponding wind resistance measures were *** as-built geometric error and cable force error were controlled in a required design range,and this whole technological achievement can be a benchmark for construction of other large span cable-stayed bridges in the future.

关键词： Sutong Bridge superstructure construction method construction control geometry control wind-resistant measure

Rock mechanical problems and optimization for the long and deep diversion tunnels at Jinping Ⅱ hydropower station

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Journal of Rock Mechanics and Geotechnical Engineering 2011年第4期3卷 314-328页

作者： Shiyong Wu Ge Wang Ertan Hydropower Development Co. Ltd. Chengdu 610051 China

According to site-specific environments such as high water pressures, high in-situ stresses and strong rockbursts, the design scheme of the long and deep diversion tunnels at Jinping II hydropower station was optimized to ensure construction safety. New drainage tunnels were considered. Furthermore, lining structures and grouting pressures were modified during the excavation of tunnels. The construction scheme was updated dynamically based on the complex geological conditions. For instances, the diversion tunnels were first excavated by drilling and blasting method at the first stage of construction, and then by the combination method of tunnel boring machine （TBM） and drilling and blasting, and finally by drilling and blasting method. Through optimized scheme and updated construction scheme, the excavation of diversion tunnel #1 was successfully completed in June, 2011. This paper summarizes the key issues in rock mechanics associated with the construction of the long and deep diversion tunnels at Jinping II hydropower station. The experiences of design and construction obtained from this project could provide reference to similar projects.

关键词： Jinping II hydropower station diversion tunnels optimized design construction method grouting