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Experimental and Simulation Analysis of Two-Tone and Three-Tone Photodetector Linearity Characterizing Systems 被引量:1
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作者 费嘉瑞 黄永清 +3 位作者 刘悠欣 刘凯 段晓峰 任晓敏 《Chinese Physics Letters》 SCIE CAS CSCD 2017年第11期110-113,共4页
Two measurement techniques are investigated to characterize photodetector linearity. A model for the two-tone and three-tone photodetector systems is developed to thoroughly investigate the influences of setup compone... Two measurement techniques are investigated to characterize photodetector linearity. A model for the two-tone and three-tone photodetector systems is developed to thoroughly investigate the influences of setup components on the measurement results. We demonstrate that small bias shifts from the quadrature point of the modulator will induce deviation into measurement results of the two-tone system, and the simulation results correspond well to experimental and calculation results. 展开更多
关键词 OIP Experimental and simulation analysis of Two-Tone and Three-Tone Photodetector Linearity Characterizing systems IMD dBm
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Design and Analysis of a Dual Rotor Turbine with a Shroud Using Flow Simulations
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作者 Peter E. Jenkins Abdalfadel Younis Yuxuan Chen 《Journal of Power and Energy Engineering》 2017年第4期25-40,共16页
This paper describes the flow simulation of a dual rotor, three-bladed wind turbine module with a shroud to determine its performance. The parameters that were evaluated are the effects of adding a second rotor, wind ... This paper describes the flow simulation of a dual rotor, three-bladed wind turbine module with a shroud to determine its performance. The parameters that were evaluated are the effects of adding a second rotor, wind speed, distance between the two rotors, the size of the front rotor and the shroud. The results were obtained by using the Solid Works 2015 flow simulation program. Also, the benefits and cost issues for wind generating systems are illustrated. 展开更多
关键词 design and analysis of a DUAL ROTOR TURBINE with a SHROUD USING Flow simulations
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Electromagnetic simulation and experimental analysis of microwave heaters for asphalt pavements 被引量:3
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作者 朱松青 张志胜 史泰龙 《Journal of Southeast University(English Edition)》 EI CAS 2011年第4期410-416,共7页
In order to study the thermoelectric efficiency of microwave heating and reproduction of asphalt pavements and the uniformity of reproduction temperature distribution, a waveguide excitation cavity is designed and app... In order to study the thermoelectric efficiency of microwave heating and reproduction of asphalt pavements and the uniformity of reproduction temperature distribution, a waveguide excitation cavity is designed and applied to the structural design of a microwave heater. The structural sizes of the incentive cavities are determined based on the waveguide transmission line theory. Using IE3D software, electromagnetic simulations are respectively carried out in four different situations, including the distances between the magnetron probes (antennas) and a short-circuit board, different horn electric lengths and aperture sizes, different dielectric properties of the asphalt mixture, and the distances between the asphalt surface and the mouth cavity. The results show that, when the distance between the magnetron probe and the short-circuit board is 32.5 ram, it is the best installation site; reduction of aerial length is the main factor in improving the heating uniformity. When the aggregate is limestone, the best heating effect can be produced. Maximum radiation efficiency can be realized by adjusting the space between the heater radiation port and the asphalt pavement. The experimental results of asphalt mixture heating in four different situations have a substantial agreement with the simulation results, which confirms that the developed microwave heater can achieve better impedance matching, thus improving the quality and efficiency of heating regeneration. 展开更多
关键词 microwave heater excitation cavity structural design electromagnetic simulation temperature distribution experimental analysis
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The Structural Design, Simulation Analysis and Parameter Optimization of the Cheetah Robot's Lumbar Vertebrae
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作者 LUO Qing-sheng KE Zhi-fang +1 位作者 ZHANG Bo-xi LIU Fang-zheng 《Computer Aided Drafting,Design and Manufacturing》 2013年第4期40-44,共5页
The quality of skeleton system for the cheetah robot goes hand in hand with its bionic result of its shape, structure and functions. In view of the skeleton system constitution and structural characteristic of the che... The quality of skeleton system for the cheetah robot goes hand in hand with its bionic result of its shape, structure and functions. In view of the skeleton system constitution and structural characteristic of the cheetah, the team applied structure design, stimulation analysis and parameter optimization to developing the cheetah robot. In addition, after the invention of cheetah robot's anterior lumbar vertebra based on its functional attribute and connectivity attribute, the Solidworks Simulation was utilized to analyze the design, according to which improvement on the lumbar vertebra was made. Plus, the advantages of the CAD and CAE made the high efficiency of design work and high quality of the cheetah robot possible. 展开更多
关键词 cheetah robot structure design stimulation analysis parameter optimization simulation
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Improving landscape Characteristics in Port Said’s El Sallam Garden via Observational and Space Syntax Analysis
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作者 Amr Ali Bayoumi 《Journal of Civil Engineering and Architecture》 2024年第3期101-111,共11页
This paper provides a comprehensive examination of El Sallam Garden in Port Said City,concentrating on its landscape characteristics and potential for design enhancement.This study looks at how space syntax can be use... This paper provides a comprehensive examination of El Sallam Garden in Port Said City,concentrating on its landscape characteristics and potential for design enhancement.This study looks at how space syntax can be used to assess the impact of a tree planting design’s spatial configuration on an urban park’s visual fields.Trees play an important role in determining the spatial characteristics of an outdoor space.According to space syntax theory,an urban area is a collection of connected spaces that can be represented by a matrix of quantitative properties known as syntactic measures.Computer simulations can be used to measure the quantitative properties of these matrices.This study uses space syntax techniques to assess how tree configurations and garden area which can affect the social structures of small-scale gardens in Port Said.It also looks at how these techniques can be used to predict the social structures of four garden zones in El Sallam Garden.The study includes an observational and space syntax study through comparative analysis of four garden zones in El Sallam garden.The results of the study show that the area and planting configurations of the garden had a significant effect on the syntactic social and visual measures of the urban garden.The conclusions and recommendations can be a useful tool for landscape architects,urban planners,and legislators who want to enhance public areas and encourage social interaction in urban settings. 展开更多
关键词 VGA(visibility graph analysis) agent simulation space syntax minimal paths garden landscape design behavioral mapping gate count
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Applying UML and Machine Learning to Enhance System Analysis and Design
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作者 Aparna Gadhi Ragha Madhavi Gondu +2 位作者 Chinna Manikanta Bandaru Keerthana Chit Reddy Olatunde Abiona 《International Journal of Communications, Network and System Sciences》 2023年第5期67-76,共10页
System analysis and design (SAD) is a crucial process in the development of software systems. The impact of modeling techniques and software engineering practices on SAD has been the focus of research for many years. ... System analysis and design (SAD) is a crucial process in the development of software systems. The impact of modeling techniques and software engineering practices on SAD has been the focus of research for many years. Two such techniques that have had a significant impact on SAD are Unified Modeling Language (UML) and machine learning. UML has been used to model the structure and behavior of software systems, while machine learning has been used to automatically learn patterns in data and make predictions. The purpose of this paper is to review the literature on the impact of UML and machine learning on SAD. We summarize the findings from several studies and highlight the key insights related to the benefits and limitations of these techniques for SAD. Our review shows that both UML and machine learning have had a positive impact on SAD, with UML improving communication and documentation, and machine learning improving the accuracy of predictions. However, there are also challenges associated with their use, such as the need for expertise and the difficulty of interpreting machine learning models. Our findings suggest that a combination of UML and machine learning can enhance SAD by leveraging the strengths of each technique. 展开更多
关键词 UML Machine Learning System analysis design IMPLEMENTATION
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High-frequency structure design and RF stability analysis of a 4-vane radio frequency quadrupole with pi-mode stabilizer loops 被引量:1
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作者 Xiao-Wen Zhu Claude Marchand +1 位作者 Olivier Piquet Michel Desmons 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2022年第3期113-125,共13页
Compact accelerator-based neutron source facilities are garnering attention and play an important and expanding role in material and engineering sciences,as well as in neutron science education and training.Neutrons a... Compact accelerator-based neutron source facilities are garnering attention and play an important and expanding role in material and engineering sciences,as well as in neutron science education and training.Neutrons are produced by bombarding a low-energy proton beam onto a beryllium or lithium target.In such an acceleratorbased neutron source,a radio frequency quadrupole(RFQ)is usually utilized to accelerate a high-intensity proton beam to a few MeV.This study mainly covers the highfrequency structure design optimizations of a 4-vane RFQ with pi-mode stabilizer loops(PISLs)and its RF stability analysis.A 176 MHz RFQ accelerator is designed to operate at a 10%duty factor and could accelerate an80 mA proton beam from 65 keV to 2.5 MeV within a length of 5.3 m.The adoption of PISLs ensures high RF stability,eases the operation of the accelerator,and implies less stringent alignment and machining tolerances. 展开更多
关键词 Accelerator-based neutron source 4-vane RFQ accelerator Pi-mode stabilizer loops Perturbative analysis Electromagnetic design Multipacting simulation
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Reliability simulation and analysis of phased-mission system with multiple states 被引量:1
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作者 SU Xujun LYU Xuezhi 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2019年第3期624-632,共9页
Basing on discrete event simulation, a reliability simulation algorithm of the phased-mission system with multiple states is put forth. Firstly, the concepts and main characters of phasedmission system are discussed, ... Basing on discrete event simulation, a reliability simulation algorithm of the phased-mission system with multiple states is put forth. Firstly, the concepts and main characters of phasedmission system are discussed, and an active and standby redundancy (AS) tree structure method to describe the system structure of each mission phase is brought forward. Secondly, the behavior of the phased-mission system with multiple states is discussed with the theory of state chart. Thirdly, basing on the discrete event simulation concept, a simulation algorithm to estimate reliability parameters of the phased-mission system with multiple states is explored. Finally, an example is introduced and analyzed, and the analysis result verifies the algorithms. The simulation algorithm is practical and versatile, for it can model complex behavior of phased-mission system flexibly, and more reliability parameters to understand system operation can be attained. 展开更多
关键词 RELIABILITY phased-mission system DISCRETE EVENT simulation simulation and analysis
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Optimization Design and Performance Analysis of Vehicle Powertrain Mounting System 被引量:5
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作者 Han Zhou Hui Liu +1 位作者 Pu Gao Chang-Le Xiang 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2018年第2期76-88,共13页
The design strategies for powertrain mounting systems play an important role in the reduction of vehicular vibration and noise. As stiffness and damping elements connecting the transmission system and vehicle body, th... The design strategies for powertrain mounting systems play an important role in the reduction of vehicular vibration and noise. As stiffness and damping elements connecting the transmission system and vehicle body, the rubber mount exhibits better vibration isolation performance than the rigid connection. This paper presents a complete design process of the mounting system, including the vibration decoupling, vibration simulation analysis, topology optimization, and experimental verification. Based on the 6?degrees?of?freedom vibration coupling model of the powertrain mounting system, an optimization algorithm is used to extract the best design parameters of each mount, thus rendering the mounting system fully decoupled and the natural frequency well configured, and the optimal parameters are used to design the mounting system. Subsequently, vibration simulation analysis is applied to the mounting system, considering both transmission and road excitations. According to the results of finite element analysis, the topological structure of the metal frame of the front mount is optimized to improve the strength and dynamic characteristics of the mounting system. Finally, the vibration bench test is used to verify the availability of the optimization design with the analysis of acceleration response and vibration transmissibility of the mounting system. The results show that the vibration isolation performance of the mounting system can be improved effectively using the vibration optimal decoupling method, and the structural modification of the metal frame can well promote the dynamic characteristics of the mounting system. 展开更多
关键词 Mounting system Optimization algorithm Vibration simulation analysis Topological structure Acceleration response Vibration transmissibility
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Safety analysis of wheel brake system based on STAMP/STPA and Monte Carlo simulation 被引量:8
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作者 HU Jianbo ZHENG Lei XU Shukui 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2018年第6期1327-1339,共13页
The wheel brake system safety is a complex problem which refers to its technical state, operating environment, human factors, etc., in aircraft landing taxiing process. Usually, professors consider system safety with ... The wheel brake system safety is a complex problem which refers to its technical state, operating environment, human factors, etc., in aircraft landing taxiing process. Usually, professors consider system safety with traditional probability techniques based on the linear chain of events. However, it could not comprehensively analyze system safety problems, especially in operating environment, interaction of subsystems, and human factors. Thus,we consider system safety as a control problem based on the system-theoretic accident model, the processes(STAMP) model and the system theoretic process analysis(STPA) technique to compensate the deficiency of traditional techniques. Meanwhile,system safety simulation is considered as system control simulation, and Monte Carlo methods are used which consider the range of uncertain parameters and operation deviation to quantitatively study system safety influence factors in control simulation. Firstly,we construct the STAMP model and STPA feedback control loop of the wheel brake system based on the system functional requirement. Then four unsafe control actions are identified, and causes of them are analyzed. Finally, we construct the Monte Carlo simulation model to analyze different scenarios under disturbance. The results provide a basis for choosing corresponding process model variables in constructing the context table and show that appropriate brake strategies could prevent hazards in aircraft landing taxiing. 展开更多
关键词 safety analysis landing taxiing system-theoretic accident model and processes(STAMP) model and system theoretic process analysis(STPA)(STAMP/STPA) feedback control loop Monte Carlo simulation
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Dynamical analysis and circuit simulation of a new three-dimensional chaotic system 被引量:1
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作者 王爱元 凌志浩 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第7期96-101,共6页
This paper reports a new three-dimensional autonomous chaotic system. It contains six control parameters and three nonlinear terms. Two cross-product terms are respectively in two equations. And one square term is in ... This paper reports a new three-dimensional autonomous chaotic system. It contains six control parameters and three nonlinear terms. Two cross-product terms are respectively in two equations. And one square term is in the third equation. Basic dynamic properties of the new system are investigated by means of theoretical analysis, numerical simulation, sensitivity to initial, power spectrum, Lyapunov exponent, and Poincar~ diagrams. The dynamic properties affected by variable parameters are also analysed. Finally, the chaotic system is simulated by circuit. The results verify the existence and implementation of the system. 展开更多
关键词 chaotic system dynamical properties circuit simulation nonlinear analysis
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Structural Design and Static Stress Analysis of Dead Pig Vehicle
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作者 ZHANG Tie-min LI Wen-tao LIANG Li 《International Journal of Plant Engineering and Management》 2017年第2期102-113,共12页
Nowadays,in our pig field there has no special device to transport those dead pigs. In normal condition,we need some person to carry out those dead pigs from the pig field.But considering the narrow aisle,manual handl... Nowadays,in our pig field there has no special device to transport those dead pigs. In normal condition,we need some person to carry out those dead pigs from the pig field.But considering the narrow aisle,manual handling is not convenient,on one hand,these measures will increase the labor costs,on the other hand,these measures will increase the labor intensity of workers. In order to carry out those dead pigs from the pig field fast and efficient,to achieve the purpose of health cultivation,in this paper,we designed a dead pig vehicle to handle those dead pigs. The dead pig vehicle consists of chassis,lifting device,driving device,rotating device,power system and control system. The vehicle adopts self-propelled structure,which is equipped with two lead-acid batteries as power. Loading,transportation,unloading and other dead pig handling full operations can finished by only one person. The result of simulation shows that the dead pig vehicle has a good performance and a good stability,it also can satisfy the requirements of the narrow aisle. The results of this research can provide reference for the similar transportation vehicles. 展开更多
关键词 VEHICLE structural design pig field simulation analysis LIVESTOCK
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Workshop on Simulation and Systems Analysis for Rice Production(SARP) held at CNRRI
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作者 ZHU Defeng,CNRRI 《Chinese Rice Research Newsletter》 1995年第4期12-12,共1页
SARP Workshop on risk analysis of agroecological zonation and optimization of crop rotation was held at CNRRI’s research center on 24—27 Oct, 1995. Experts from Philippines, India, China, and IRRI were present in th... SARP Workshop on risk analysis of agroecological zonation and optimization of crop rotation was held at CNRRI’s research center on 24—27 Oct, 1995. Experts from Philippines, India, China, and IRRI were present in the workshop. Participants exchanged the research results on the field of land use, soil erosion. optimization of rice—wheat, rice—peanut, rice—corn cropping system in the different environments, risk analysis of rice based cropping system, nitrogen balance in rice based cropping system with system approach, demonstrated models used in their studies, and discussed the ongoing cooperative research. 展开更多
关键词 simulation held at CNRRI Workshop on simulation and systems analysis for Rice Production SARP
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Design and Kinematic Analysis of a Driving Roller-type No-till Seeding and Hole-forming System
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作者 Liu Hong-xin Gai Guang-wei +1 位作者 Su Hang Wang Deng-yu 《Journal of Northeast Agricultural University(English Edition)》 CAS 2019年第2期60-74,共15页
Conventional no-till seeders should cut or remove crop straw and residue,when in operation and thus present a number of problems,including high performance requirements for the cutting component,high power consumption... Conventional no-till seeders should cut or remove crop straw and residue,when in operation and thus present a number of problems,including high performance requirements for the cutting component,high power consumption,dust raising and interference from intertwined straw.In view of this,in this study,a driving roller dibbling-type no-till seeding and hole-forming(DGR-NT-SHF)system was designed to be capable of penetrating soil and creating holes without requiring any special preparation of the surface covering.The core mechanism of this system consisted of a land wheel-driven driving roller and a duckbill-type roller seeder,which were internally tangent to one another.The rotating roller rolled the straw into a thin layer,and the duckbills extended from the roller and penetrated this thin layer of straw and subsequently formed the holes and planted the seeds.Based on kinematic analysis,a mathematical model was established to depict the relations between the rear angle of the duckbill(α),the front angle of the duckbill(β),the angular velocity of the duckbill-type roller seeder(ω0),the angular velocity of the roller(ω1),and the aperture of the duckbill outlet on the roller(θ).In contrast to a driven roller-type no-till seeding and hole-forming DNR-NT-SHF system,several parameters of the DGR-NT-SHF system were established for planting seeds at a plant spacing that was an integral multiple of 100 mm:the radius of the duckbill-type roller seeder,200 mm;radius of the roller,400 mm;α,23°;andβ,5°.Based on the analysis of the models using the MATLAB Image Processing Module with a relation betweenω1 and the number of outlets on the roller as the constraint,the optimal number of outlets on the roller and theω1/ω0 ratio were determined to be 21 and 4/7,respectively.Kinematic simulation on a digital prototype was performed using computer aided three-dimensional interactive application(CATIA)to observe the motion of the DGR-NT-SHF system,when the duckbills on the duckbill-type roller seeder were open and to determine the locations of the duckbills relative to the outlets.To ensure the duckbills could be successfully opened,the chord length of the outlets was ultimately determined to be 71 mm.The prototype test results showed that the DGR-NT-SHF system met the design requirements and that the operation was straightforward and reliable.In addition,compared to the DNR-NT-SHF system,the DGR-NT-SHF system performed better in penetration and exerted no impact on the duckbills,thus providing an effective technical option for no-till seeding. 展开更多
关键词 NO-TILL SEEDING hole-forming system driving ROLLER kinematic analysis simulation
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Design and Maxwell 3D simulation of small permanent magnetic actuator
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作者 Zhang Guangcai Xu Yajie +2 位作者 Chang Yan Chen Qiaoyan Yang Xiaodong 《Engineering Sciences》 EI 2014年第3期70-76,共7页
According to the magnetic circuit design theory and performance requirements of magnetic field, an H-type permanent magnetic actuator that generates uniform magnetic field larger than 0.4 T in the interested re- gion ... According to the magnetic circuit design theory and performance requirements of magnetic field, an H-type permanent magnetic actuator that generates uniform magnetic field larger than 0.4 T in the interested re- gion has been designed in this paper. The static magnetic field simulation analysis was done by Ansoft' s Max- well three-dimensional (3D) software. The simulation results showed that the magnetic field of this system can meet the requirements, and this permanent magnetic actuator designed in this paper can be used in small nuclear magnetic resonance (NMR) svstem. 展开更多
关键词 NMR PERMANENT MAGNET magnetic circuit design MAXWELL 3D simulation FINITE element analy-sis
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A User Friendly Approach for Design and Economic Analysis of Standalone SPV System
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作者 Sheeraz Kirmani 《Smart Grid and Renewable Energy》 2015年第4期67-74,共8页
This paper presents the use of solar energy for generation of electrical energy through solar pho-tovoltaic (SPV) system to meet the load requirement of a domestic building. Complete design and economic analysis of SP... This paper presents the use of solar energy for generation of electrical energy through solar pho-tovoltaic (SPV) system to meet the load requirement of a domestic building. Complete design and economic analysis of SPV system for different costs of SPV module is done and compared with grid electricity for with and without storage conditions. The results of the study encourage the use of SPV system for a residential building and show that SPV system is an economically viable option to meet the exponentially growing electricity requirement for household applications in India. 展开更多
关键词 HOUSEHOLD ELECTRIFICATION Solar Photovoltaics SPV System design Cost analysis
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Optimum Designing of Gas Distribution Networks of Ilam Province by Using GIS Network and Spatial Analysis
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作者 Hosein Anvari Bakhtiar Feizizadeh Rasool Olyani Nejad 《Open Journal of Geology》 2016年第8期801-811,共11页
Undoubtedly, pipeline transport is considered as significant economical artery of country and national valuable resources, so it is necessary to use latest technologies, major standards and instructions and the best h... Undoubtedly, pipeline transport is considered as significant economical artery of country and national valuable resources, so it is necessary to use latest technologies, major standards and instructions and the best human resources in designing, operation and supervision in construction and also protection of it. Also, all authorities and involved of construction and operation of gas industries installation should observe safety criteria, health and environment and aware of them ever. In fact, in designing of these programs, in addition to technical and economical points, environmental characteristics should be considered in order to their construction has minimum damage to environment. On the other hand, common and traditional approaches of pipeline routing are based on using costly and time-consuming methods. In these methods, it is not easily to use all effective parameters in determining optimum way. According to capability of analysis of network spatial information systems in incorporation of spatial data, for using all effective parameters in routing, this environment is used, therefore weighted overlay analysis (Boleyn, index and fuzzy) and shortest path are modeled for finding optimum path of pipeline in GIS environment. 展开更多
关键词 designing Optimum Path Hierarchical analysis Environmental Parameters Geographical Information System
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Comprehensive evaluation of high-steep slope stability and optimal high-steep slope design by 3D physical modeling 被引量:3
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作者 Xing-ping Lai Peng-fei Shan +2 位作者 Mei-feng Cai Fen-hua Ren Wen-hui Tan 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2015年第1期1-11,共11页
High-steep slope stability and its optimal excavation design in Shuichang open pit iron mine were analyzed based on a large 3D physical simulation technique. An optimal excavation scheme with a relatively steeper slop... High-steep slope stability and its optimal excavation design in Shuichang open pit iron mine were analyzed based on a large 3D physical simulation technique. An optimal excavation scheme with a relatively steeper slope angle was successfully implemented at the northwest wall between Nos. 4 and 5 exploration lines of Shuichang Iron Mine, taking into account the 3D scale effect. The phys-ico-mechanical properties of rock materials were obtained by laboratory tests conducted on sample cores from exploration drilling directly from the iron mine. A porous rock-like composite material was formed for the model, and the mechanical parameters of the material were assessed experimentally;specifically, the effect of water on the sample was quantitatively determined. We adopted an experimental setup using stiff modular applied static loading to carry out a visual excavation of the slope at a random depth. The setup was equipped with acous-tic emission (AE) sensors, and the experiments were monitored by crack optical acquirement, ground penetrating radar, and close-field pho-togrammetry to investigate the mechanisms of rock-mass destabilization in the high-steep slope. For the complex study area, the model re-sults indicated a clear correlation between the model's destabilization resulting from slope excavation and the collected monitoring informa-tion. During the model simulation, the overall angle of the slope increased by 1-6 degrees in different sections. Dramatically, the modeled excavation scheme saved over 80 million tons of rock from extraction, generating enormous economic and ecological benefits. 展开更多
关键词 slope stability analysis EXCAVATION design three-dimensional models physical simulation
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Probabilistic fragility analysis:A tool for assessing design rules of RC buildings 被引量:1
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作者 Nikos D Lagaros 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2008年第1期45-56,共12页
In this work, fragility analysis is performed to assess two groups of reinforced concrete structures. The first group of structures is composed of buildings that implement three common design practices; namely, fully ... In this work, fragility analysis is performed to assess two groups of reinforced concrete structures. The first group of structures is composed of buildings that implement three common design practices; namely, fully infilled, weak ground story and short columns. The three design practices are applied during the design process of a reinforced concrete building. The structures of the second group vary according to the value of the behavioral factors used to define the seismic forces as specified in design procedures. Most seismic design codes belong to the class of prescriptive procedures where if certain constraints are fulfilled, the structure is considered safe. Prescriptive design procedures express the ability of the structure to absorb energy through inelastic deformation using the behavior factor. The basic objective of this work is to assess both groups of structures with reference to the limit-state probability of exceedance. Thus, four limit state fragility curves are developed on the basis of nonlinear static analysis for both groups of structures. Moreover, the 95% confidence intervals of the fragility curves are also calculated, taking into account two types of random variables that influence structural capacity and seismic demand. 展开更多
关键词 probabilistic fragility analysis design practice behavior factor Monte Carlo simulation method
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Novel sensitivity analysis method and dynamics optimization for multiple launch rocket systems 被引量:1
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作者 Tu Tianxiong Wang Guoping +1 位作者 Rui Xiaoting Miao Yunfei 《Journal of Southeast University(English Edition)》 EI CAS 2022年第1期15-19,共5页
This study establishes the launch dynamics method,sensitivity analysis method,and multiobjective dynamic optimization method for the dynamic simulation analysis of the multiple launch rocket system(MLRS)based on the R... This study establishes the launch dynamics method,sensitivity analysis method,and multiobjective dynamic optimization method for the dynamic simulation analysis of the multiple launch rocket system(MLRS)based on the Riccati transfer matrix method for multibody systems(RMSTMM),direct differentiation method(DDM),and genetic algorithm(GA),respectively.Results show that simulation results of the dynamic response agree well with test results.The sensitivity analysis method is highly programming,the matrix order is low,and the calculation time is much shorter than that of the Lagrange method.With the increase of system complexity,the advantage of a high computing speed becomes more evident.Structural parameters that have the greatest influence on the dynamic response include the connection stiffness between the pitching body and the rotating body,the connection stiffness between the rotating body and the vehicle body,and the connection stiffnesses among 14^(#),16^(#),and 17^(#)wheels and the ground,which are the optimization design variables.After optimization,angular velocity variances of the pitching body in the revolving and pitching directions are reduced by 97.84%and 95.22%,respectively. 展开更多
关键词 Riccati transfer matrix method for multibody systems multiple launch rocket system launch dynamics sensitivity analysis optimization design
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