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A Study on Physical Model Test for Cheongpyeong Dam Discharge Recalculation 被引量:1
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作者 Joongu Kang Sungjoong Kim Hongkoo Yeo 《Engineering(科研)》 2014年第11期731-742,共12页
Cheongpyeong Dam was built in 1943 for the purpose of power generation. Since its construction, discharge flow data based on a theoretical formula have been used to the present times and this leads to a problem of acc... Cheongpyeong Dam was built in 1943 for the purpose of power generation. Since its construction, discharge flow data based on a theoretical formula have been used to the present times and this leads to a problem of accurate discharge flow information not being available. In particular, Cheongpyeong Dam has been partially repaired and modified to maintain the dam structure over a long period of time and is not being properly reflected with changes at the downstream of the river caused by river improvement projects and sedimentation in reservoir. With a goal to improve Cheongpyeong Dam discharge flow calculation, this study aimed at verifying discharge capability and discharge flow by damper opening in relation to the previously suggested discharge flow through a hydraulic model test based on an accurate reproduction of the dam structure and surrounding topographies as in the present conditions. In this study, a hydraulic model test was conducted to examine the discharge flow of Cheongpyeong Dam. In addition, a comparative examination was carried out against the existing discharge flow proposed using theoretical equations. As a verification of the discharge flow of Cheongpyeong Dam, discharge flows in all sluices and a single sluice were examined. Then, the impact of sluice interference caused by the dam structure consisting with 24 sluices was investigated. As a result of the examination, it was found that the difference between discharge flow calculated using the existing theoretical equations and discharge flow derived from the hydraulic model test was insignificant. Based on the results of hydraulic model test, a formula to estimate stage-discharge flow at a sluice was derived and suggested. 展开更多
关键词 Cheongpyeong DAM hydraulic model test STAGE-DISCHARGE CURVE Recalculation
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Design and Test of Closed Hydraulic Transmission System of 4WD High-clearance Wheeled Sprayer
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作者 Hengfeng CHEN Xiaobo XU 《Plant Diseases and Pests》 2024年第3期14-20,共7页
In conjunction with the working characteristics of the high-clearance wheeled sprayer and the benefits of the closed hydraulic system,a series of reasonable working parameters should be established,and a hydraulic sys... In conjunction with the working characteristics of the high-clearance wheeled sprayer and the benefits of the closed hydraulic system,a series of reasonable working parameters should be established,and a hydraulic system that fulfills the requisite specifications should be designed.The AMESim software model is employed to construct a closed hydraulic transmission system,and the simulation analysis is then performed according to the data of hydraulic components.According to analysis results,the prototype can be optimized and upgraded,and a verification test is further carried out.The test results demonstrate that the designed closed hydraulic transmission system meets the actual working requirements of the high-clearance wheeled sprayer and provides a stable experimental platform for intelligent control of agricultural machinery. 展开更多
关键词 Closed hydraulic transmission system High-clearance Wheeled sprayer modeling and simulation Verification test
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Modelling Design and Test of Steam Centrifugal Compressor
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作者 秦仁 牛利民 郑群 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 1997年第2期34-38,共5页
This paper discusses the modeling design and accuracy analysis of a single stage steam centrifugal compressor for China′S first seawater desalinization plant, and gives a brief presentation on the closed loop vapou... This paper discusses the modeling design and accuracy analysis of a single stage steam centrifugal compressor for China′S first seawater desalinization plant, and gives a brief presentation on the closed loop vapour test platform designed and constructed for qualification of the compress or for performance and operational reliability, and results of tests run with the compressor. Both tests and actual operation show the modeling design is successful, and the compressor achieved and exceeded what was expected in performance. The seawater desalinization plant has run with excellent performance and reliability for several years for the national seawater desalinization demonstration program. This proves it is practical and practicable to develop and design China′s steam centrifugal compressors in series from air centrifugal compressors by maintaining equal specific volume ratio at both inlet and outlet of the compressor. 展开更多
关键词 STEAM CENTRIFUGAL COMPRESSOR modelLING design STEAM closed circuit test
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Angular Position Controller and Its Design Model Verification for the Electro-Hydraulic Servo Control System 被引量:1
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作者 KARAM M. Elbayomy 《Computer Aided Drafting,Design and Manufacturing》 2007年第1期60-65,共6页
The angular position controller is system (EHSAS) to control the output of the rotary applied to electro-hydraulic servo actuator actuator. It works as a compensator based on the frequency response of the EHSAS. Its... The angular position controller is system (EHSAS) to control the output of the rotary applied to electro-hydraulic servo actuator actuator. It works as a compensator based on the frequency response of the EHSAS. Its design model is verified on the state-space model of EHSAS by using simulation program SIMULINK. Real data used to test the system. Simulation results give a good agreement for the controller and also for the state-space model. 展开更多
关键词 angular position controller electro-hydraulic servo control system design model state-space model SIMULINK
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Life prediction and test period optimization research based on small sample reliability test of hydraulic pumps 被引量:5
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作者 郭锐 Ning Chao +4 位作者 Zhao Jingyi Wang Ping Shi Yu Zhou Jinsheng Luo Jing 《High Technology Letters》 EI CAS 2017年第1期63-70,共8页
Hydraulic pumps belong to reliable long-life hydraulic components. The reliability evaluation includes characters such as long test period,high cost,and high power loss and so on. Based on the principle of energy-savi... Hydraulic pumps belong to reliable long-life hydraulic components. The reliability evaluation includes characters such as long test period,high cost,and high power loss and so on. Based on the principle of energy-saving and power recovery,a small sample hydraulic pump reliability test rig is built,and the service life of hydraulic pump is predicted,and then the sampling period of reliability test is optimized. On the basis of considering the performance degradation mechanism of hydraulic pump,the feature information of degradation distribution of hydraulic pump volumetric efficiency during the test is collected,so an optimal degradation path model of feature information is selected from the aspect of fitting accuracy,and pseudo life data are obtained. Then a small sample reliability test of period constrained optimization search strategy for hydraulic pump is constructed to solve the optimization problem of the test sampling period and tightening end threshold,and it is verified that the accuracy of the minimum sampling period by the non-parametric hypothes is tested. Simulation result shows it could possess instructional significance and referenced value for hydraulic pump reliability life evaluation and the test's research and design. 展开更多
关键词 hydraulic pump small sample test volumetric efficiency degradation path model life span period optimal
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Inverse modelling of aquifer parameters in basaltic rock with the help of pumping test method using MODFLOW software 被引量:1
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作者 Kanak Moharir Chaitanya Pande Sanjay Patil 《Geoscience Frontiers》 SCIE CAS CSCD 2017年第6期1385-1395,共11页
The origin and movement of groundwater are the fundamental questions that address both the temporal and spatial aspects of ground water run and water supply related issues in hydrological systems.As groundwater flows ... The origin and movement of groundwater are the fundamental questions that address both the temporal and spatial aspects of ground water run and water supply related issues in hydrological systems.As groundwater flows through an aquifer,its composition and temperature may variation dependent on the aquifer condition through which it flows.Thus,hydrologic investigations can also provide useful information about the subsurface geology of a region.But because such studies investigate processes that follow under the Earth's shallow,obtaining the information necessary to answer these questions is not continuously easy.Springs,which discharge groundwater table directly,afford to study subsurface hydrogeological processes.The present study of estimation of aquifer factors such as transmissivity(T)and storativity(S)are vital for the evaluation of groundwater resources.There are several methods to estimate the accurate aquifer parameters(i.e.hydrograph analysis,pumping test,etc.).In initial days,these parameters are projected either by means of in-situ test or execution test on aquifer well samples carried in the laboratory.The simultaneous information on the hydraulic behavior of the well(borehole)that provides on this method,the reservoir and the reservoir boundaries,are important for efficient aquifer and well data management and analysis.The most common in-situ test is pumping test performed on wells,which involves the measurement of the fall and increase of groundwater level with respect to time.The alteration in groundwater level(drawdown/recovery)is caused due to pumping of water from the well.Theis(1935)was first to propose method to evaluate aquifer parameters from the pumping test on a bore well in a confined aquifer.It is essential to know the transmissivity(T=Kb,where b is the aquifer thickness;pumping flow rate,Q=TW(dh/dl)flow through an aquifer)and storativity(confined aquifer:S=bS_s,unconfined:S=S_y),for the characterization of the aquifer parameters in an unknown area so as to predict the rate of drawdown of the groundwater table/potentiometric surface throughout the pumping test of an aquifer.The determination of aquifer's parameters is an important basis for groundwater resources evaluation,numerical simulation,development and protection as well as scientific management.For determining aquifer's parameters,pumping test is a main method.A case study shows that these techniques have been fast speed and high correctness.The results of parameter's determination are optimized so that it has important applied value for scientific research and geology engineering preparation. 展开更多
关键词 PUMPING test Hantush method GPS MODFLOW INVERSE modelling hydraulic parameters
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Novel method for operating characteristics test of a hydraulic pump
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作者 王向周 陆叶 郑戍华 《Journal of Beijing Institute of Technology》 EI CAS 2015年第1期74-82,共9页
The traditional testing method of a hydraulic pump requires a large amount of test data from a variety of pump working conditions. The test is usually time-consuming and energy-consu- ming. And the accurate characteri... The traditional testing method of a hydraulic pump requires a large amount of test data from a variety of pump working conditions. The test is usually time-consuming and energy-consu- ming. And the accurate characteristic curves of the pump were hardly obtained due to a limited a- mount and discreteness of the test data. In order to simplify the test procedure and improve the test accuracy, a novel method for measuring hydraulic pump operating characteristic based on multi-ele- ment nonlinear regression (NLMR) modeling is proposed in this paper. The main idea of this model- ing method is establishing a mathematical model to predict the performance parameters of the hy- draulic pump, only a small amount of test data is needed. Consequently, the pump operating charac- teristics in any working conditions are obtained. And the test results of the pump are easily charac- terized in the graphs, charts, tables and so on. The evaluations of the model are carried out and dis- cussed in this paper. The result shows that the test error of the novel method can be controlled to be about 0. 1%. Compared with the traditional test method, the proposed method reduces greatly the test time and the random error of the test data, and improves the efficiency and accuracy of the pump test. 展开更多
关键词 hydraulic pump test model work characteristics
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Exponential System Reliability Test Design Based on Information Fusion
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作者 刘琦 张安扬 《Journal of Donghua University(English Edition)》 EI CAS 2016年第2期323-326,共4页
By analyzing the shortage of reliability test design and thinking over the producer's risk and consumer's risk, the information fusion technology is used to set up a reliability test design model( RTDM). By an... By analyzing the shortage of reliability test design and thinking over the producer's risk and consumer's risk, the information fusion technology is used to set up a reliability test design model( RTDM). By analyzing the demands and constraint conditions of the RTDM and with applications of Bayesian approach and Monte Carlo method( MCM),this paper puts forward the exponential distributed subsystems and the information fusion technology among them. According to the posteriori risk criteria,formulas of producer's risk and consumer's risk were also inferred,and with the help of Matlab software,selection of the optimum test plan was solved. Finally,validity of the model had been proved by a test of series parallel system. 展开更多
关键词 reliability test design information fusion reliability test design model(RTDM) Bayesian approach Monte Carlo method(MCM)
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On the Analysis Method of the Triple Test Cross Design
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作者 Jin Yi(Northeast Agricultural University, Harbin 1 50030, P R C) 《Journal of Northeast Agricultural University(English Edition)》 CAS 1995年第1期66-74,共9页
The analysis method of the triple test cross design has been discussed carefully from the two factor experiment design and the genetic models of additive dominant effect and of epistasis effect.Two points different f... The analysis method of the triple test cross design has been discussed carefully from the two factor experiment design and the genetic models of additive dominant effect and of epistasis effect.Two points different from the previous reports have been concluded: (1)both the degrees of freedom of the orthogonal terms C2 and C3 are m, (2)the denominator in the F test to C2 and C3 is the error mean of square between plots. 展开更多
关键词 Triple test cross design Additive-dominant model Epistasis model Genetic parameter estimate.
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Automatic lifting system design and application of large load powered support test rig
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作者 LIU Xin-ke 《Journal of Coal Science & Engineering(China)》 2012年第4期428-431,共4页
This paper presented a design of an automatic lifting system. It is used for large load powered support and improves the old method wherein powered support lifting depends on manual control. This system applies a high... This paper presented a design of an automatic lifting system. It is used for large load powered support and improves the old method wherein powered support lifting depends on manual control. This system applies a high accuracy gear shunt motor to match the flow for 4 lifting cylinders, and also allocates bypass throttles to realize automatic lifting. Through the dis- placement sensor feedback the height deviation among 4 lifting cylinders during the whole lifting process, when the deviation is up to the sitting value, the corresponding bypass throttle is operated immediately to reduce the deviation, so that the moving platform of the powered support would not be stuck. Through real application, it is shown that this system can realize automatic lifting of powered support; the lifting speed is controlled between 5 and 10 mm/s, and the final aligning accuracy is up to 1 mm. 展开更多
关键词 powered support automatic lift hydraulic system design test rig large load
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Model-Based Control Design Using SLPS "Simulink PSpice Interface" 被引量:1
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作者 Saied Moslehpour Ercan K. Kulcu Hisham Alnajjar 《通讯和计算机(中英文版)》 2010年第5期68-77,共10页
关键词 SIMULINK模型 PSPICE 控制设计 基于模型 SLP 程序接口 仿真模拟器 MATLAB
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An Application of Paraconsistent Annotated Logic for Design Software Testing Strategies
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作者 Marcos Ribeiro do Nascimento Luiz Alberto Vieira Dias Joao Inacio Da Silva Filho 《Journal of Software Engineering and Applications》 2014年第5期371-386,共16页
Nowadays, application model systems for decision-making based on non-classical logic such as Paraconsistent Logic are used successfully in the treatment of uncertainties. The method presented in this paper is based on... Nowadays, application model systems for decision-making based on non-classical logic such as Paraconsistent Logic are used successfully in the treatment of uncertainties. The method presented in this paper is based on the fundamental concepts of Paraconsistent Annotated Logic with annotation of 2 values (PAL2v). In this study, two algorithms based on PAL2v are presented gradually, to extract the effects of the contradiction in signals of information from a database of uncertain knowledge. The Paraconsistent Extractors Algorithms of Contradiction Effect-Para Extrctr is applied to filters of networks of analyses (PANets) of signal information, where uncertain and contradictory signals may be found. Software test case scenarios are subordinated to an application model of Paraconsistent decision-making, which provides an analysis using Paraconsistent Logic in the treatment of uncertainties for design software testing strategies. This quality-quantity criterion to evaluate the software product quality is based on the characteristics of software testability analysis. The Para consistent reasoning application model system presented in this case study, reveals itself to be more efficient than the traditional methods because it has the potential to offer an appropriate treatment to different originally contradicting source information. 展开更多
关键词 Paraconsistent LOGIC design testing STRATEGIES SOFTWARE testABILITY Paraconsistent DECISION MAKING model
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Model Design and Development of a Telescopic Palm Fruit Harvester
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作者 Peter Okechukwu Chikelu 《Modern Mechanical Engineering》 CAS 2023年第1期1-20,共20页
This research paper presents a comprehensive conceptual design approach for the development of a telescopic machine system, which is portable and will provide a safe method of harvesting palm fruits. For this machine ... This research paper presents a comprehensive conceptual design approach for the development of a telescopic machine system, which is portable and will provide a safe method of harvesting palm fruits. For this machine system development, the material for each component of the machine system was first selected, the boom length, maximum boom angle, force and stroke length of each hydraulic cylinder, the hydraulic pump pressure, base weight, permissible weight of the cutting system and power required were then calculated in the design analysis. Furthermore, from the calculated parameters, the model of the system was created using SolidWorks engineering software, the model was developed and tested. The result shows that the cutting time of the system for one bunch of palm fruit was longer when compared to conventional systems. It was concluded that though the machine is maintenance friendly and portable, further improvements in its design are necessary so as to develop a system that will give desirable economic output at a shorter time. 展开更多
关键词 design model TELESCOPIC Palm Fruit Harvester BOOM MAST hydraulic Cylinder Solidworks
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Quantifying Reusability of Object Oriented Design: A Testability Perspective
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作者 Mahfuzul Huda Yagya Dutt Sharma Arya Mahmoodul Hasan Khan 《Journal of Software Engineering and Applications》 2015年第4期175-183,共9页
The quality factor of class diagram is critical because it has a significant influence on overall quality of the product, delivered finally. Testability analysis, when done early in the software creation process, is a... The quality factor of class diagram is critical because it has a significant influence on overall quality of the product, delivered finally. Testability analysis, when done early in the software creation process, is a criterion of critical importance to software quality. Reusability is an important quality factor to testability. Its early measurement in object oriented software especially at design phase, allows a design to be reapplied to a new problem without much extra effort. This research paper proposes a research framework for quantification process and does an extensive review on reusability of object oriented software. A metrics based model “Reusability Quantification of Object Oriented Design” has been proposed by establishing the relationship among design properties and reusability and justifying the correlation with the help of statistical measures. Also, “Reusability Quantification Model” is empirically validated and contextual significance of the study shows the high correlation for model acceptance. This research paper facilitates to software developers and designer, the inclusion of reusability quantification model to access and quantify software reusability for quality product. 展开更多
关键词 REUSABILITY testABILITY OBJECT ORIENTED design design Metrics OBJECT ORIENTED SOFTWARE SOFTWARE Quality model SOFTWARE testing Effort
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Design and Characterization of an Aerosol Test Chamber for Emergency Response Patient Contamination Control Simulation and Research
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作者 Megan L. Steele Emily M. Spatz +4 位作者 George P. Lemmer Jacob M. Denney Jeremy M. Slagley Casey W. Cooper Robert M. Eninger 《Occupational Diseases and Environmental Medicine》 2023年第1期78-96,共19页
Contaminated or infected patients present a risk of cross-contamination for emergency responders, attending medical personnel and medical facilities as they enter a treatment facility. The controlled conditions of an ... Contaminated or infected patients present a risk of cross-contamination for emergency responders, attending medical personnel and medical facilities as they enter a treatment facility. The controlled conditions of an aerosol test chamber are required to examine factors of contamination, decontamination, and cross-contamination. This study presents the design, construction, and a method for characterizing an aerosol test chamber for a full-sized manikin on a standard North Atlantic Treaty Organization litter. The methodology combined air velocity measurements, aerosol particle counts and size distributions, and computational fluid dynamics modeling to describe the chamber’s performance in three dimensions. This detailed characterization facilitates future experimental design by predicting chamber performance for a variety of patient-focused research. 展开更多
关键词 test Chamber Characterization Aerosol Generation Exposure Chamber design Air Velocity Mapping Spatial Variability CFD modeling Patient Decontamination
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Accelerating Life Test Scheme and Modeling Method for Machinegun
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作者 Yong-Hai SHAN Xian-Ming GAO Shi-Qi SHAN Zheng-Gang NIE 《Journal of Mathematics and System Science》 2015年第6期262-268,共7页
There is a pressing need for improving the current whole life shooting method in order to reduce ammunition consumption in the firearms lifetime test. The influencing factors, the characterization parameters and the c... There is a pressing need for improving the current whole life shooting method in order to reduce ammunition consumption in the firearms lifetime test. The influencing factors, the characterization parameters and the correlation analysis result of lifetime were considered. Accelerating life test and measuring scheme for machinegun were designed systematically by applying such theoretical methods as accelerating test, uniform design and lifetime model. As result, it provides a more scientific and reasonable accelerating life test scheme and proposes methods on modeling lifetime, optimizing model and characterizing lifetime. The conclusion can be used in preparing accelerating life test scheme and lifetime model for machinegun. 展开更多
关键词 Machinegun BARREL LIFETIME design test model
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The Test Models' Comparison of College English Assessment
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作者 汪晓琳 《海外英语》 2016年第22期217-218,共2页
With the influence of test model for College English curriculum, test models and English teaching ways cannot be ignored. We should pay more attention to the reorganization of the new assessment system, which can impr... With the influence of test model for College English curriculum, test models and English teaching ways cannot be ignored. We should pay more attention to the reorganization of the new assessment system, which can improve their learning efficiency, stimulate students' learning interest and promote English teaching. 展开更多
关键词 test model curricula design curriculum requirement
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An Efficient Reliability-Based Optimization Method Utilizing High-Dimensional Model Representation and Weight-Point Estimation Method
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作者 Xiaoyi Wang Xinyue Chang +2 位作者 Wenxuan Wang Zijie Qiao Feng Zhang 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第5期1775-1796,共22页
The objective of reliability-based design optimization(RBDO)is to minimize the optimization objective while satisfying the corresponding reliability requirements.However,the nested loop characteristic reduces the effi... The objective of reliability-based design optimization(RBDO)is to minimize the optimization objective while satisfying the corresponding reliability requirements.However,the nested loop characteristic reduces the efficiency of RBDO algorithm,which hinders their application to high-dimensional engineering problems.To address these issues,this paper proposes an efficient decoupled RBDO method combining high dimensional model representation(HDMR)and the weight-point estimation method(WPEM).First,we decouple the RBDO model using HDMR and WPEM.Second,Lagrange interpolation is used to approximate a univariate function.Finally,based on the results of the first two steps,the original nested loop reliability optimization model is completely transformed into a deterministic design optimization model that can be solved by a series of mature constrained optimization methods without any additional calculations.Two numerical examples of a planar 10-bar structure and an aviation hydraulic piping system with 28 design variables are analyzed to illustrate the performance and practicability of the proposed method. 展开更多
关键词 Reliability-based design optimization high-dimensional model decomposition point estimation method Lagrange interpolation aviation hydraulic piping system
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Optimal Design of Equivalent Water Depth Truncated Mooring System Based on Baton Pattern Simulated Annealing Algorithm 被引量:3
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作者 张火明 黄赛花 管卫兵 《China Ocean Engineering》 SCIE EI CSCD 2014年第1期67-80,共14页
The highest similarity degree of static characteristics including both horizontal and vertical restoring force-displacement characteristics of total mooring system, as well as the tension-displacement characteristics ... The highest similarity degree of static characteristics including both horizontal and vertical restoring force-displacement characteristics of total mooring system, as well as the tension-displacement characteristics of the representative single mooring line between the truncated and full depth system are obtained by annealing simulation algorithm for hybrid discrete variables (ASFHDV, in short). A“baton” optimization approach is proposed by utilizing ASFHDV. After each baton of optimization, if a few dimensional variables reach the upper or lower limit, the boundary of certain dimensional variables shall be expanded. In consideration of the experimental requirements, the length of the upper mooring line should not be smaller than 8 m, and the diameter of the anchor chain on the bottom should be larger than 0.03 m. A 100000 t turret mooring FPSO in the water depth of 304 m, with the truncated water depth being 76 m, is taken as an example of equivalent water depth truncated mooring system optimal design and calculation, and is performed to obtain the conformation parameters of the truncated mooring system. The numerical results indicate that the present truncated mooring system design is successful and effective. 展开更多
关键词 hybrid model testing deep sea platforms equivalent water depth truncation FPSO optimization design baton optimization approach
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Investigation on Optimization Design of an Equivalent Water Depth Truncated Mooring System Based on INSGA-Ⅱ 被引量:1
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作者 Huoming Zhang Wenjun Gao Qiang Wang Juan Jiang Zhou Zhao 《Journal of Marine Science and Application》 2012年第2期208-215,共8页
At present,equivalent water depth truncated mooring system optimization design is regarded as the priority of hybrid model testing for deep sea platforms,and will replace the full depth system test in the future.Compa... At present,equivalent water depth truncated mooring system optimization design is regarded as the priority of hybrid model testing for deep sea platforms,and will replace the full depth system test in the future.Compared with the full depth system,the working depth and span are smaller in the truncated one,and the other characteristics maintain more consistency as well.In this paper,an inner turret moored floating production storage & offloading system(FPSO) which works at a water depth of 320m,was selected to be a research example while the truncated water depth was 80m.Furthermore,an improved non-dominated sorting genetic algorithm(INSGA-II) was selected to optimally calculate the equivalent water depth truncated system,considering the stress condition of the total mooring system in both the horizontal and vertical directions,as well as the static characteristic similarity of the representative single mooring line.The results of numerical calculations indicate that the mathematical model is feasible,and the optimization method is fast and effective. 展开更多
关键词 deep sea platforms hybrid model test equivalent water depth truncated mooring system optimization design
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