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construction method of Shape Adjustable Bézier Triangles

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Chinese Journal of Electronics 2019年第3期28卷 610-617页

作者： YAN Lanlan School of Science East China University of Technology

Aiming at the drawback that the shape of Bézier triangles is fixed with respect to the control points,some blending functions with parameter and with similar properties to the bivariate Bernstein polynomials are presented. Few literatures introduce how do the blending functions are derived. This paper aims at providing the general construction method of adjustable Bézier triangles in polynomial space. With the help of degree elevation technique and based on the idea that the adjustable surfaces are defined by the adjustable control points, the shape adjustable Bézier triangles are *** construction process of the blending functions is demonstrated in detail.

关键词： B′ezier triangle Shape adjustment Shape parameter construction method

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

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

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

A Survey of Steel Arch Bridges in China

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Journal of Civil Engineering and Architecture 2011年第9期5卷 799-808页

作者： Baochun Chen Kangming Chen Shozo Nakamura Qiu Zhao College of Civil Engineering Fuzhou University Fuzhou Fujian 350108 China College of Civil and Environmental Engineering Nagasaki University Nagasaki 852-8521 Japan

A review of the current status and progress of steel arch bridges in China is presented in this paper. The existing steel arch bridges in China were analyzed in terms of steel material, span, structure type, main arch rib form and construction method. The comparison with CFST arch bridges and RC arch bridges is also conducted. It is shown that steel arch bridge has gain rapid development in China since 2000, characterized by long main spans. As for the span, most of the steel arch bridges have a span less than 250 m, while when the span exceeds 350 m, steel arch bridges are strongly competitive against CFST or RC arch bridges. Over 80% of the bridges are through and half-through bridge types, and the arch ribs are hingeless structures. The rise-to-span ratios of the arches are mainly between 1：4 and 1： 5. Most of the arches use solid box ribs, and a small portion of arches use truss ribs in which box sections are mostly adopted for the truss members. The cantilever method and scaffolding method are the two main construction methods used, but some other construction methods have also been developed.

关键词： Steel arch bridge survey bridge type rib construction method China