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Study on the Optimum Moisture Amount Added to Brown Rice once during the Wet Conditioning 被引量:7
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作者 BAI Shi-gang JIA Fu-guo NAN Jing-fu 《Journal of Northeast Agricultural University(English Edition)》 CAS 2005年第2期137-140,共4页
In the experiment, the brown rice whose moisture content was 12.5% was used as raw material. The brown rice was grouped, then moisturized differently and milled. While milling, the energy consumption, the rate of brok... In the experiment, the brown rice whose moisture content was 12.5% was used as raw material. The brown rice was grouped, then moisturized differently and milled. While milling, the energy consumption, the rate of broken rice and the crack rate were tested. It is confirmed that the stress crack owing to the moisture added to the brown rice can be avoided when the moisture amount added once is limited to no more than 1.5%. It is also proved that the energy consumption can be reduced, the yielding rate of rice can be increased and that the quality of rice can be improved. 展开更多
关键词 brown rice rice milling moisture conditioning the optimum moisture amount added once
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SmartMicro Grid Energy System Management Based on Optimum Running Cost for Rural Communities in Rwanda
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作者 Fabien Mukundufite Jean Marie Vianney Bikorimana Alexander Kyaruzi Lugatona 《Energy Engineering》 EI 2024年第7期1805-1821,共17页
The governmental electric utility and the private sector are joining hands to meet the target of electrifying all households by 2024.However,the aforementioned goal is challenged by households that are scattered in re... The governmental electric utility and the private sector are joining hands to meet the target of electrifying all households by 2024.However,the aforementioned goal is challenged by households that are scattered in remote areas.So far,Solar Home Systems(SHS)have mostly been applied to increase electricity access in rural areas.SHSs have continuous constraints to meet electricity demands and cannot run income-generating activities.The current research presents the feasibility study of electrifying Remera village with the smart microgrid as a case study.The renewable energy resources available in Remera are the key sources of electricity in that village.The generation capacity is estimated based on the load profile.The microgrid configurations are simulated with HOMER,and the genetic algorithm is used to analyze the optimum cost.By analyzing the impact of operation and maintenance costs,the results show that the absence of subsidies increases the levelized cost of electricity(COE)five times greater than the electricity price from the public utility.The microgrid made up of PV,diesel generator,and batteries proved to be the most viable solution and ensured continuous power supply to customers.By considering the subsidies,COE reaches 0.186$/kWh,a competitive price with electricity from public utilities in Rwanda. 展开更多
关键词 Load demand load profile optimum running cost power demand satisfaction smart meters and smart micro grid
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Determination of the Series Resistance of a Series Vertical-Junction Silicon (N+/P/P+) Solar Cell under Polychromatic Illumination and Magnetic Field: Effect of Optimum Thickness
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作者 Dibor Faye Babou Dione +1 位作者 Mountaga Boiro Pape Diop 《Journal of Modern Physics》 2024年第10期1543-1554,共12页
By solving the magneto-transport equation for excess minority charge carriers in the base of the series vertical-junction silicon cell, the phenomenological parameters of the cell can be determined from the boundary c... By solving the magneto-transport equation for excess minority charge carriers in the base of the series vertical-junction silicon cell, the phenomenological parameters of the cell can be determined from the boundary conditions. Photocurrent density and photovoltage are determined for each value of applied magnetic field and corresponding optimum thickness, to establish the current-voltage characteristic (Jph(Sf, Sb, z, B, Hop)-Vph(Sf, Sb, z, B, Hop) of the silicon cell under polychromatic illumination. This study will make it possible to reduce the material used (by reducing the optimum thickness), which will help to lower prices. It will also enable us to reduce betting effects (lower series resistance), thereby boosting solar cell efficiency. 展开更多
关键词 Series Vertical Junction Silicon Cell Static Regime Magnetic Field optimum Thickness Series Resistance
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OPTIMUM OF PRESSURE RATIOS OF MULTI-STAGE RECIPROCATING COMPRESSOR WITH PRACTICAL INTER-COOLING 被引量:1
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作者 刘卫华 昂海松 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2002年第2期177-181,共5页
The optimum pressure ratio distribution of a multistage reciprocating compressor is presented based on the assumption, i.e. the inter stage cooling is perfect and there are no pressure losses. The optimization of the... The optimum pressure ratio distribution of a multistage reciprocating compressor is presented based on the assumption, i.e. the inter stage cooling is perfect and there are no pressure losses. The optimization of the two or three stage pressure ratio is analyzed in two cases of constant heat transfer rate for the inter cooler or constant inter stage inlet temperature, based on the minimum of the sum of theoretical compression power at each stage about a multi stage reciprocating compressor. Furthermore, with an example of two stage compressor the influence on the sum of the power of each stage is analyzed when practical pressure ratio deviates from the optimum value. It is obtained that under different cooling conditions the optimum pressure ratio distribution of the multi stage compression is various, and the change of the optimum pressure ratio within a small range has little influence on the sum of the power each stage. For the two stage compression, this range can be represented as ε 1=(0 96~1 06)ε 1j . 展开更多
关键词 inter cooler multi stage compressor pressure ratio optimum
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Analysis and Optimum Design of Differential Inductors Using Distributed Capacitance Model
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作者 菅洪彦 唐长文 +1 位作者 何捷 闵昊 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2005年第6期1077-1082,共6页
A distributed capacitance model for monolithic inductors is developed to predict the equivalently parasitical capacitances of the inductor.The ratio of the self-resonant frequency (f SR) of the differential-driven sym... A distributed capacitance model for monolithic inductors is developed to predict the equivalently parasitical capacitances of the inductor.The ratio of the self-resonant frequency (f SR) of the differential-driven symmetric inductor to the f SR of the single-ended driven inductor is firstly predicted and explained.Compared with a single-ended configuration,experimental data demonstrate that the differential inductor offers a 127% greater maximum quality factor and a broader range of operating frequencies.Two differential inductors with low parasitical capacitance are developed and validated. 展开更多
关键词 distributed capacitance model self-resonant frequency ratio quality factor differential inductor optimum design
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Study on Optimum Fertilization Model of Potato Intercropped with Sugarcane
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作者 江泽普 廖青 +5 位作者 谭裕模 韦广泼 邢颖 汪羽宁 刘斌 梁潘霞 《Agricultural Science & Technology》 CAS 2013年第1期138-143,共6页
[Objective] The paper was to study the effects of different ratios of N, P and K on yield of potato intercropped with sugarcane in Lateritic red earth area of Guangxi, and seek the best N, P and K ratio for nutrition ... [Objective] The paper was to study the effects of different ratios of N, P and K on yield of potato intercropped with sugarcane in Lateritic red earth area of Guangxi, and seek the best N, P and K ratio for nutrition model of potato inter- cropped with sugarcane. [Method]Two field experiments adopted the optimum com- pound design (311-A) were conducted in Long'an County of Guangxi Province in 2011 and 2012, respectively. The polynomial regression models of fertilizer applica- tion and quadratic of three factors were established by SAS statistical analysis soft- ware, and optimum nutrient simulation models of potato were obtained by computer processing. [Result] The combined application of low nitrogen and mid-high potassi- um and phosphorus fertilizer contributed to higher potato yield in experimental condi- tion. The regression model of potato yield (Yll and Y12) and dosage of N(X1), P (X2), K(X3) were established by using SAS statistical analysis software, in 2011 and 2012, respectively. They were Y11 =14 725.28 -415.39X1 +741.99X2 +607.83)(3-447.92X1X2- 144.09X1X3 -405.83X2X3 -267.82X1^2-795.67X2^2 -642.10X3^2, R =0.927 2; and Y12 =14 342.60 -896.25X1 +548.62X2 +925.51 X3 +67.81 X1X2 +531.60X1X3 -99.00X2X3 -904.00X1^2 - 1121.36X2^2-596.64X3^2,R=0.926 6. The regression mathematics model of potato yields preferably fit with actual situation in the locality, and have higher practical value, so it could be used for fertilizer decision and forecast. Using the computer to carry on the optimization, the N, P and K dosage of the best potato yield intercropped with sugarcane was obtained. The dosage of N, P2O5, K2O were 108.8-140.6, 172.5-204.4 and 285.9 kg/hm2, respectively. [Conclusion] The best N, P and K ratio of potato yield intercropped with sugarcane was 1:(1.23-1.68):(2.03-2.63). 展开更多
关键词 INTERCROPPING optimum fertilization model Sugarcane-Potato
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DYNAMICAL OPTIMUM DESIGN OF THE MECHANICAL OSCILLATION SYSTEM IN FLUIDIC GENERATOR
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作者 李福松 陈建军 《兵工学报》 EI CAS CSCD 北大核心 2000年第1期-,共4页
文中通过对射流发电机工作原理、结构特点及作用荷载的分析,建立了射流发电机机械振动系统的动力优化设计数学模型,以结构尺寸为设计变量,使结构重量极小化,满足动力位移、应力响应、基频以及尺寸限等约束条件,利用振型迭加法和复... 文中通过对射流发电机工作原理、结构特点及作用荷载的分析,建立了射流发电机机械振动系统的动力优化设计数学模型,以结构尺寸为设计变量,使结构重量极小化,满足动力位移、应力响应、基频以及尺寸限等约束条件,利用振型迭加法和复合形法求解。优化和试验结果表明:经优化后,既减轻结构重量,又显著地提高了射流发电机的输出功率。 展开更多
关键词 引信 射流技术 电源 有限元法 动力响应 动力优化 DYNAMICAL optimum DESIGN OF THE MECHANICAL
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Optimum Design of Impedance Simulator for Phased Array Antnnas
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作者 吕昕 李世智 《Journal of Beijing Institute of Technology》 EI CAS 1994年第1期63+59-63,共6页
The impedance of a solid state active phased array antenna varing with frequency and beam scanning scanning angle be matched with the solid state active matching network (SSAMN). In order to adjust and measure the rad... The impedance of a solid state active phased array antenna varing with frequency and beam scanning scanning angle be matched with the solid state active matching network (SSAMN). In order to adjust and measure the radar conveniently and Securely, it is necessary for the impedance of the simulator of the phased array antennas to be optimized.Having selected the PIN dilde controlling circuits and the circuit parameters optimized,the simulator circuit is determined through numerical computation The experiment is given in support of the simulation. 展开更多
关键词 phase array antennas impedance inatching simulation optimum design active circuits
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OPTIMUM CUTTING ANALYSIS METHOD OF MEMBRANE STRUCTURE
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作者 邵小方 吴健生 《Transactions of Tianjin University》 EI CAS 1995年第2期189+186-187,189,共4页
By the optimum theory, a new cutting analytical method of the membrane structure is developed. The B-spline curve is applied to make smooth the boundary of the membrane strip. By this method, the cutting accuracy is i... By the optimum theory, a new cutting analytical method of the membrane structure is developed. The B-spline curve is applied to make smooth the boundary of the membrane strip. By this method, the cutting accuracy is improved. Finally, a cutting analysis example of a tension membrane structure is given. 展开更多
关键词 membrane structure cutting analysis optimum theory
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Is There an Optimum Age For Foreign Language Learning?
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作者 兰军 《陕西师范大学学报(哲学社会科学版)》 CSSCI 北大核心 2001年第S2期334-336,共3页
Age is one of the factors which influnce foreign language learning, but not the most important one. Comparision on the effect of foreign language learning between adults and children cannot rely merely on age. So the ... Age is one of the factors which influnce foreign language learning, but not the most important one. Comparision on the effect of foreign language learning between adults and children cannot rely merely on age. So the question of an optimum age for foreign language learning is not a simple one which is only related to age. There are different optimum ages for different aims and demands of learning foreign language. 展开更多
关键词 optimum age FOREIGN LANGUAGE LEARNING ADULT CHILDREN
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Fuzzy Optimum Model of Semi-Structural Decision for Lectotype Optimization of Offshore Platforms 被引量:10
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作者 陈守煜 伏广涛 +1 位作者 王建明 刘刚 《China Ocean Engineering》 SCIE EI 2001年第4期453-466,共14页
In the process of concept design of offshore platforms, it is necessary to select the best from feasible alternatives through comparison and filter. The criterion set, used to evaluate and select the satisfying altern... In the process of concept design of offshore platforms, it is necessary to select the best from feasible alternatives through comparison and filter. The criterion set, used to evaluate and select the satisfying alternative, consists of many qualitative and quantitative factors. Therefore, the selection is a problem of multicriteria and semi-structural decision-making. Different from traditional methods in semi-structural decision-making, a new framework and methodology is presented in this paper for evaluation of offshore platform alternatives, First, the criterion set is established for the evaluation of alternatives. Next, the approach is studied to construct the relative membership degree matrix, in which both qualitative and quantitative factors are consistent with the uniform calculating standard. And then a new weight-assessing method is developed for calculation of the weights based on the relative membership degree matrix. Finally, a multi-hierarchy fuzzy optimum model is adopted to select the satisfying offshore platform alternative. A case study shows that the new framework and methodology are scientific, reasonable and easy to use in practice. 展开更多
关键词 offshore platform lectotype optimization semi-structure relative membership degree matrix weightvector fuzzy optimum
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Limit equilibrium analysis for stability of soil nailed slope and optimum design of soil nailing parameters 被引量:5
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作者 DENG Dong-ping LI Liang ZHAO Lian-heng 《Journal of Central South University》 SCIE EI CAS CSCD 2017年第11期2496-2503,共8页
Reinforcement of slopes using soil nailing can effectively improve slope stability, and it has been widely used in upgrading cut slopes. Based on the assumptions of stresses on the slip surface, a new method for analy... Reinforcement of slopes using soil nailing can effectively improve slope stability, and it has been widely used in upgrading cut slopes. Based on the assumptions of stresses on the slip surface, a new method for analyzing the stability of a slope reinforced with soil nails was established in the limit equilibrium theory framework, by considering that slope sliding occurs owing to shear failure of the slip surface, which subjects to Mohr–Coulomb(M–C) strength criterion. Meanwhile, in order to easily analyze the stability of a soil nailed slope in actual engineering and facilitate optimum design of parameters for soil nailing, factor of safety(FOS) contour curve charts were drawn on the basis of the established linear proportional relationship between the spacing of soil nails and slope height, and the length of soil nails and slope height. Then, by analyzing and verifying the results obtained from classic examples, some conclusions can be got as follows: 1) The results obtained from the current method are close to those obtained from the traditional limit equilibrium methods, and the current method can provide a strict solution for the slope FOS as it satisfies all the static equilibrium conditions of a sliding body, thus confirming the feasibility of the current method; 2) The slope FOS contour curve charts can be used not only to reliably analyze the stability of a soil nailed slope, but also to design optimally the parameters of soil nailing for the slope with a certain safety requirement. 展开更多
关键词 SLOPE STABILITY soil NAILING LIMIT EQUILIBRIUM factor of safety CONTOUR curve optimum design
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Optimum Weight Design of Functionally Graded Material Gears 被引量:7
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作者 JING Shikai ZHANG He +1 位作者 ZHOU Jingtao SONG Guohua 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2015年第6期1186-1193,共8页
Traditional gear weight optimization methods consider gear tooth number, module, face width or other dimension parameters of gear as design variables. However, due to the complicated form and geometric features peculi... Traditional gear weight optimization methods consider gear tooth number, module, face width or other dimension parameters of gear as design variables. However, due to the complicated form and geometric features peculiar to the gear, there will be large amounts of design parameters in gear design, and the influences of gear parameters changing on gear trains, transmission system and the whole equipment have to be taken into account, which increases the complexity of optimization problem. This paper puts forward to apply functionally graded materials(FGMs) to gears and then conduct the optimization. According to the force situation of gears, the material distribution form of FGM gears is determined. Then based on the performance parameters analysis of FGMs and the practical working demands for gears, a multi-objective optimization model is formed. Finally by using the goal driven optimization(GDO) method, the optimal material distribution is achieved, which makes gear weight and the maximum deformation be minimum and the maximum bending stress do not exceed the allowable stress. As an example, the applying of FGM to automotive transmission gear is conducted to illustrate the optimization design process and the result shows that under the condition of keeping the normal working performance of gear, the method achieves in greatly reducing the gear weight. This research proposes a FGM gears design method that is able to largely reduce the weight of gears by optimizing the microscopic material parameters instead of changing the macroscopic dimension parameters of gears, which reduces the complexity of gear weight optimization problem. 展开更多
关键词 GEARS optimum weight design functionally graded materials material distribution additive manufacturing
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Atlas Based Kinematic Optimum Design of the Stewart Parallel Manipulator 被引量:6
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作者 SHAO Zhufeng TANG Xiaoqiang +1 位作者 WANG Liping SUN Dengfeng 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2015年第1期20-28,共9页
Optimum design is a key approach to make full use of potential advantages of a parallel manipulator. The optimum design of multi-parameter parallel manipulators(more than three design parameters), such as Stewart ma... Optimum design is a key approach to make full use of potential advantages of a parallel manipulator. The optimum design of multi-parameter parallel manipulators(more than three design parameters), such as Stewart manipulator, relies on analysis based and algorithm based optimum design methods, which fall to be accurate or intuitive. To solve this problem and achieve both accurate and intuition, atlas based optimum design of a general Stewart parallel manipulator is established, with rational selection of design parameters. Based on the defined spherical usable workspace(SUW), primary kinematic performance indices of the Stewart manipulator involving workspace and condition number are introduced and analyzed. Then, corresponding performance atlases are drawn with the established non-dimensional design space, and impact of joint distribution angles on the manipulator performance is analyzed and illustrated. At last, an example on atlas based optimum design of the Stewart manipulator is accomplished to illustrate the optimum design process, considering the end-effector posture. Deduced atlases can be flexibly applied to both quantitative and qualitative analysis to get the desired optimal design for the Stewart manipulator with respect to related performance requirements. Besides, the established optimum design method can be further applied to other multi-parameter parallel manipulators. 展开更多
关键词 optimum design performance atlas parallel mechanism STEWART
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Optimum Design for Shrink-fit Multi-layer Vessels under Ultrahigh Pressure Using Different Materials 被引量:6
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作者 YUAN Gexia LIU Hongzhao WANG Zhongrnin 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2010年第5期582-589,共8页
Multi-layer pressure vessels are widely used in every field of high pressure technology.For the purpose of enhancing a vessels' load bearing capacity,a beneficial process like shrink-fit is usually employed.However,f... Multi-layer pressure vessels are widely used in every field of high pressure technology.For the purpose of enhancing a vessels' load bearing capacity,a beneficial process like shrink-fit is usually employed.However,few documents on optimum design for multi-layer shrink-fit vessels made of different strength materials can be found,available data are mainly on two-layer vessels.In this paper,an optimum design approach is developed for shrink-fit multi-layer vessels under ultrahigh pressure by using different materials.Maximum shear stress theory is applied as design criteria.The inner and outer radii of a multi-layer vessel,as well as the material of each layer,are assumed to be known.The optimization mathematical model is,thereby,built.Lagrange multipliers method is required to obtain the optimal design formula of wall ratio(ratio of outer to inner radii) of each layer,from which the optimum formulas of shrinkage pressure and radial interference are derived with the superposition principle employed.These formulas are applicable for the optimization design of all multi-layer vessels made of different materials,or same materials.The formulas of the limit working pressure and the contact pressure show that the optimum wall ratio of each layer and limit working pressure are only related to all selected material strength and unrelated to the position of the layer placement in the vessel.However,shrinkage pressure is related to the position of the layer placement in the vessel.Optimization design of an open ended shrink-fit three-layer vessel using different materials and comparisons proved that the optimized multi-layer vessels have outstanding characteristics of small radial interference and are easier for assembly.When the stress of each layer is distributed more evenly and appropriately,the load bearing capability and safety of vessels are enhanced.Therefore,this design is material-saving and cost-effective,and has prospect of engineering application. 展开更多
关键词 multi-layer vessels Lagrange multiplier shrink-fit optimum interference maximum shear stress theory
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Global Optimum-Based Search Differential Evolution 被引量:8
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作者 Yang Yu Shangce Gao +1 位作者 Yirui Wang Yuki Todo 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2019年第2期379-394,共16页
In this paper, a global optimum-based search strategy is proposed to alleviate the situation that the differential evolution(DE) usually sticks into a stagnation, especially on complex problems. It aims to reconstruct... In this paper, a global optimum-based search strategy is proposed to alleviate the situation that the differential evolution(DE) usually sticks into a stagnation, especially on complex problems. It aims to reconstruct the balance between exploration and exploitation, and improve the search efficiency and solution quality of DE. The proposed method is activated by recording the number of recently consecutive unsuccessful global optimum updates. It takes the feedback from the global optimum,which makes the search strategy not only refine the current solution quality, but also have a change to find other promising space with better individuals. This search strategy is incorporated with various DE mutation strategies and DE variations. The experimental results indicate that the proposed method has remarkable performance in enhancing search efficiency and improving solution quality. 展开更多
关键词 Differential evolution(DE) global optimum memetic algorithm
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AN OPTIMUM VEHICULAR PATH ALGORITHM FOR TRAFFIC NETWORK BASED ON HIERARCHICAL SPATIAL REASONING 被引量:4
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作者 Lu Feng Zhou Chenghu Wan Qing 《Geo-Spatial Information Science》 2000年第4期36-42,共7页
Human beings’ intellection is the characteristic of a distinct hierarchy and can be taken to construct a heuristic in the shortest path algorithms.It is detailed in this paper how to utilize the hierarchical reasonin... Human beings’ intellection is the characteristic of a distinct hierarchy and can be taken to construct a heuristic in the shortest path algorithms.It is detailed in this paper how to utilize the hierarchical reasoning on the basis of greedy and directional strategy to establish a spatial heuristic,so as to improve running efficiency and suitability of shortest path algorithm for traffic network.The authors divide urban traffic network into three hierarchies and set forward a new node hierarchy division rule to avoid the unreliable solution of shortest path.It is argued that the shortest path,no matter distance shortest or time shortest,is usually not the favorite of drivers in practice.Some factors difficult to expect or quantify influence the drivers’ choice greatly.It makes the drivers prefer choosing a less shortest,but more reliable or flexible path to travel on.The presented optimum path algorithm,in addition to the improvement of the running efficiency of shortest path algorithms up to several times,reduces the emergence of those factors,conforms to the intellection characteristic of human beings,and is more easily accepted by drivers.Moreover,it does not require the completeness of networks in the lowest hierarchy and the applicability and fault tolerance of the algorithm have improved.The experiment result shows the advantages of the presented algorithm.The authors argued that the algorithm has great potential application for navigation systems of large_scale traffic networks. 展开更多
关键词 optimum PATH algorithm TRAFFIC NETWORK HIERARCHICAL spatial REASONING
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Optimum design and layout of the cooling apparatus for long compaignship blast furnace 被引量:10
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作者 ShusenCheng TianjunYang +3 位作者 QingguoXue HaibinZuo XiaowuGao WeiguoYang 《Journal of University of Science and Technology Beijing》 CSCD 2003年第4期24-28,共5页
Generally, the cooler life can determine the blast furnace life. Theslag-metal skull frozen on the cooler can separate the cooler from the hot gas flow in blastfurnace. The key problem is how to freeze liquid slag-met... Generally, the cooler life can determine the blast furnace life. Theslag-metal skull frozen on the cooler can separate the cooler from the hot gas flow in blastfurnace. The key problem is how to freeze liquid slag-metal on the cooler, and the main measure isto decrease the hot surface temperature of the cooler. The computational technology of heat transferwas practically used for long campaign blast furnace design. The optimum design of the cast ironstave, copper stave, plate-stave combined system and flange stave was given by the computingresults. According to the results, the optimum arrangement of different coolers (cast iron or copperstave, flange stave and plate-stave combined system) on different height of blast furnace wall canbe found through all these temperature fields. 展开更多
关键词 blast furnace COOLER optimum layout COMPUTATIONAL
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Multi-stage optimum design of magazine type automatic tool changer arm 被引量:5
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作者 KIM Jae-Hyun LEE Choon-Man 《Journal of Central South University》 SCIE EI CAS 2012年第1期174-178,共5页
To enhance machining efficiency,tool change time has to be reduced.Thus,for an automatic tool changer attached to a machining center,the tool change time is to be reduced.Also the automatic tool changer is a main part... To enhance machining efficiency,tool change time has to be reduced.Thus,for an automatic tool changer attached to a machining center,the tool change time is to be reduced.Also the automatic tool changer is a main part of the machining center as a driving source.The static attributes of the automatic tool changer using the commercial code,ANSYS Workbench V12,were tried to interpret.And the optimum design of automatic tool changer arm was proposed by performing the multi-stage optimum design.The shape optimization of the automatic tool changer was proposed and the result was verified to obtain acceptable improvements.It is possible to obtain an optimized model in which the maximum deformation,maximum stress,and mass are reduced by 10.46%,12.89% and 9.26%,respectively,compared with those of the initial model.Also,the results between conventional method by the design of experiments and proposed method by the multi-stage optimum design method were compared. 展开更多
关键词 automatic tool changer optimum design structural analysis exchange arm
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Optimum placement and characteristics of velocity-dependent dampers under seismic excitation 被引量:3
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作者 Seyed Amin Mousavi Amir K.Ghorbani-Tanha 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2012年第3期403-414,共12页
In this study, through novel drift-based equations of motion in the frequency domain, optimum placement and characteristics of linear velocity-dependent dampers are investigated. In this study, the sum of the square o... In this study, through novel drift-based equations of motion in the frequency domain, optimum placement and characteristics of linear velocity-dependent dampers are investigated. In this study, the sum of the square of the absolute values of transfer matrix elements for interstory drifts is considered as the optimization index. Optimum placement and characteristics of dampers are simultaneously obtained by minimizing the optimization index through an incremental procedure. In each step of the procedure, a predefined value is considered as the damper characteristic. The optimum story for this increment is selected such that it leads to a minimum value for the optimization index. The procedure is repeated for the next increments until the optimization index meets its target value, which is obtained according to the desired damping ratio for the overall structure. In other words, the desired overall damping ratio is the input to the proposed procedure, and the optimal placement and characteristics of the dampers are its output. It is observed that the optimal placement of a velocitydependent damper depends on the damping coefficient of the added damper, frequency of the excitation, and distribution of the mass, stiffness, and inherent damping of the main structure. 展开更多
关键词 passive control velocity-dependent damper optimum placement optimum damping transfer matrix storydamping coefficient
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