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利用Cole-Cole模型组合得到SIP真参数的联合频谱最优化反演 被引量:7
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作者 张辉 李桐林 《西北地震学报》 CSCD 北大核心 2004年第2期108-112,共5页
利用Cole-Cole模型组合和稀释系数理论,可以描述测量得到的视复电阻率频谱与地下多个电性体SIP真参数之间的正演关系。本文利用此正演关系进行反演试算,并比较了几种Cole-Cole模型反演方案的效果;提出固定极化目标体和围岩体的极化率同... 利用Cole-Cole模型组合和稀释系数理论,可以描述测量得到的视复电阻率频谱与地下多个电性体SIP真参数之间的正演关系。本文利用此正演关系进行反演试算,并比较了几种Cole-Cole模型反演方案的效果;提出固定极化目标体和围岩体的极化率同时反演其它各SIP真参数的反演方案。结果表明在固定极化率为真值时,利用此反演方案可以稳定、准确、快速地得出地下电性体SIP真参数。 展开更多
关键词 Cole-Cole模型组合 最优化联合反演 稀释系数 SIP真参数
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岩矿石标本真电参数的测试方法与测试系统(WXE)的研制 被引量:2
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作者 王庆乙 邱钢 +2 位作者 代丽 王生 徐立忠 《物探与化探》 CAS CSCD 2014年第4期787-792,共6页
现有岩矿标本电参数的测试系统,所测的都是视电参数。本文研究了测试岩矿标本真电参数的方法。它通过测试系统隐含的本底电参数,将实测的视参数转换为真参数。据此,研制了新型岩矿标本真电参数测试系统(WXE)。
关键词 岩矿石标本 标本测定 真参数 极化率 电阻率
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舰载武器系统定型(鉴定)试验中某些参数的真值研究
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作者 陆祯林 《舰船论证参考》 2003年第1期17-22,共6页
本文简术了在舰载武器系统定型(鉴定)试验中为确定一些参数的精度,必须设法获取这此参数的真值,而这些参数(如目标速度及射击参数)的真值不是绝对的、孤立的,它必须与武器系统进行火控解算时所采用的惯性参照系相一致,否则就会... 本文简术了在舰载武器系统定型(鉴定)试验中为确定一些参数的精度,必须设法获取这此参数的真值,而这些参数(如目标速度及射击参数)的真值不是绝对的、孤立的,它必须与武器系统进行火控解算时所采用的惯性参照系相一致,否则就会造成偏差,失去真值的意义。 展开更多
关键词 舰载武器系统 定型试验 参数 矢量 目标运动参数 射击参数
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PARAMETER IDENTIFICATION OF LUGRE FRICTION MODEL FOR FLIGHT SIMULATION SERVO SYSTEM BASED ON ANT COLONY ALGORITHM 被引量:4
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作者 段海滨 王道波 +1 位作者 朱家强 黄向华 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2004年第3期179-183,共5页
In light of the high nonlinearity of LuGre friction model, a novel method based on ant colony algorithm(ACA) for identifying the friction parameters of flight simulation servo system is proposed. ACA is a parallelized... In light of the high nonlinearity of LuGre friction model, a novel method based on ant colony algorithm(ACA) for identifying the friction parameters of flight simulation servo system is proposed. ACA is a parallelized bionic optimization algorithm inspired from the behavior of real ants, and a kind of positive feedback mechanism is adopted in ACA. On the basis of brief introduction of LuGre friction model, a method for identifying the static LuGre friction parameters and the dynamic LuGre friction parameters using ACA is derived. Finally, this new friction parameter identification scheme is applied to a electric-driven flight simulation servo system with high precision. Simulation and application results verify the feasibility and the effectiveness of the scheme. It provides a new way to identify the friction parameters of LuGre model. 展开更多
关键词 parameter identification LuGre friction mo-del flight simulation servo system
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视复电阻率频谱的一种近似反演方法 被引量:18
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作者 罗延钟 方胜 《地球科学》 EI CAS 1986年第1期93-102,共10页
基于稀释系数不随频率变化的假设,导出了复电阻率视频谱与真频谱及柯尔-柯尔频散视参数与真参数之间的近似关系式。通过对理论视频谱进行的反演和计算证明,即使在稀释系数幅值随频率的相对变化达100%的情况下,选用特征频率的稀释系数值... 基于稀释系数不随频率变化的假设,导出了复电阻率视频谱与真频谱及柯尔-柯尔频散视参数与真参数之间的近似关系式。通过对理论视频谱进行的反演和计算证明,即使在稀释系数幅值随频率的相对变化达100%的情况下,选用特征频率的稀释系数值,所导出的视参数与真参数的近似关系式仍有实用价值。从而为频谱激电法资料的反演,计算极化体真参数提供了一种简便而有效的近似方法。 展开更多
关键词 稀释系数 柯尔-柯尔频散 参数 真参数 反演 视频谱
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A New Chaotic Parameters Disturbance Annealing Neural Network for Solving Global Optimization Problems 被引量:15
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作者 MAWei WANGZheng-Ou 《Communications in Theoretical Physics》 SCIE CAS CSCD 2003年第4期385-392,共8页
Since there were few chaotic neural networks applicable to the global optimization, in this paper, we propose a new neural network model ? chaotic parameters disturbance annealing (CPDA) network, which is superior to ... Since there were few chaotic neural networks applicable to the global optimization, in this paper, we propose a new neural network model ? chaotic parameters disturbance annealing (CPDA) network, which is superior to other existing neural networks, genetic algorithms, and simulated annealing algorithms in global optimization. In the present CPDA network, we add some chaotic parameters in the energy function, which make the Hopfield neural network escape from the attraction of a local minimal solution and with the parameter annealing, our model will converge to the global optimal solutions quickly and steadily. The converge ability and other characters are also analyzed in this paper. The benchmark examples show the present CPDA neural network's merits in nonlinear global optimization. 展开更多
关键词 Hopfield neural network global optimization chaotic parameters disturbance simulated annealing
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CCS水电站尾水渠边坡稳定及支护方案研究 被引量:3
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作者 梁成彦 邹红英 李江 《人民黄河》 CAS 北大核心 2019年第7期107-110,115,共5页
CCS水电站尾水渠所在位置属高烈度地震带,地质条件差,深覆盖层,基岩面高程变幅大,且尾水渠距离进出厂房的唯一交通要道非常近,直接导致尾水渠开挖范围受限,形成了高陡边坡稳定问题。该工程非常少见地集多种难点和复杂条件于一身,是疑难... CCS水电站尾水渠所在位置属高烈度地震带,地质条件差,深覆盖层,基岩面高程变幅大,且尾水渠距离进出厂房的唯一交通要道非常近,直接导致尾水渠开挖范围受限,形成了高陡边坡稳定问题。该工程非常少见地集多种难点和复杂条件于一身,是疑难边坡设计的典型案例,为保证工程安全,设计中采用“多参数真值反演分析”手段确定地质参数,并提出地连墙、预应力锚索、冠梁约束型抗滑桩、预应力锚杆、砂浆锚杆等多种措施联合支护的设计理念,保证了道路通畅,避免了另设进厂道路对厂房施工工期的重大延误。目前电站运行良好,尾水边坡各项安全监测数据长期收敛无异常,证明边坡整体设计理念及支护方案是合理性的。 展开更多
关键词 高烈度 深覆盖层 开挖范围受限 参数值反演分析 联合支护 安全监测 CCS水电站
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Effects of expanding zone parameters of vacuum dust suction mouth on flow simulation results 被引量:9
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作者 章易程 杨春朝 +3 位作者 Chris Baker 陈默 邹翔 戴万林 《Journal of Central South University》 SCIE EI CAS 2014年第6期2547-2552,共6页
Based on the parametric analysis of the expanding zone of the vacuum dust suction mouth,the flow in the vacuum dust suction mouth was simulated by computational fluid dynamics(CFD)software,Fluent.The effects of the ex... Based on the parametric analysis of the expanding zone of the vacuum dust suction mouth,the flow in the vacuum dust suction mouth was simulated by computational fluid dynamics(CFD)software,Fluent.The effects of the expanding zone parameters on flow simulation were analyzed.The results show that simulation effects depend on threshold values of the expanding zone parameters of the dust suction mouth,and the threshold values of the expanding zone can be obtained according to the different structures of the vacuum dust suction mouth and be selected as the geometric parameters in calculating,and also corners of the expanding zone make unobvious difference in calculation accuracy and in computational efficiency compared with no corner.The simulation results provide practical guidance to the flow simulation on the dust suction mouth. 展开更多
关键词 dust suction mouth expanding zone threshold analysis computational fluid dynamics
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Quantum Entanglement and Nonlocality Properties of Two-Mode Squeezed Thermal States in a Common-Reservoir Model 被引量:4
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作者 向少华 宋克慧 +1 位作者 文伟 施振刚 《Communications in Theoretical Physics》 SCIE CAS CSCD 2011年第2期232-238,共7页
We study a system consisting of two identical non-interacting single-mode cavity fields coupled to a common vacuum environment and provide general, explicit, and exact solutions to its master equation by means of the ... We study a system consisting of two identical non-interacting single-mode cavity fields coupled to a common vacuum environment and provide general, explicit, and exact solutions to its master equation by means of the characteristic function method. We analyze the entanglement dynamics of two-mode squeezed thermal state in this model and show that its entanglement dynamics is strongly determined by the two-mode squeezing parameter and the purity. In particular, we find that two-mode squeezed thermal state with the squeezing parameter r ≤ -(1/2) In √u is extremely fragile and almost does not survive in a common vacuum environment. We investigate the time evolution of nonlocality for two-mode squeezed thermal state in such an environment. It is found that the evolved state loses its nonlocality in the beginning of the evolution, but after a time, the revival of nonlocality can occur. 展开更多
关键词 keytwo-mode squeezed thermal state ENTANGLEMENT Bell's inequality environmental noise
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Impact of Convective Momentum Transport by Deep Convection on Simulation of Tropical Intraseasonal Oscillation 被引量:1
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作者 LING Jian LI Chongyin 《Journal of Ocean University of China》 SCIE CAS 2014年第5期717-727,共11页
This paper focuses on the impacts of convective momentum transport(CMT) on simulations of the tropical intraseasonal oscillation(TIO) in SAMIL. Two sets of experiments are performed, which give different reality of th... This paper focuses on the impacts of convective momentum transport(CMT) on simulations of the tropical intraseasonal oscillation(TIO) in SAMIL. Two sets of experiments are performed, which give different reality of the Madden-Julian Oscillation(MJO). The Tiedtke cumulus parameterization scheme is used for all experiments. It is found that simulations of the TIO can be influenced by CMT, and the impacts on the simulated TIO depend on the model capability in simulating the MJO. CMT tends to have large influences to the model that can simulate the eastward propagation of the MJO. CMT can further influence the long-term mean of zonal wind and its vertical shear. Zonal wind suffers from easterlies biases at low level and westerlies biases at upper level when CMT is introduced. Such easterlies biases at low level reduce the reality of the simulated tropical intraseasonal oscillation. When CMT is introduced in the model, MJO signals disappear but the model's mean state improves. Therefore, a more appropriate way is needed to introduce CMT to the model to balance the simulated mean state and TIO signals. 展开更多
关键词 Madden-Julian Oscillation(MJO) convective momentum transport(CMT) SAMIL
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Simulation of quasi-dimensional model for diesel engine working process 被引量:1
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作者 齐鲲鹏 冯立岩 +2 位作者 冷先银 田江平 隆武强 《Journal of Central South University》 SCIE EI CAS 2010年第4期868-872,共5页
In order to satisfy the demand of validity and real time operating performance of diesel engine model used in hardware-in-the-loop simulation system,a simplified quasi-dimensional model for diesel engine working proce... In order to satisfy the demand of validity and real time operating performance of diesel engine model used in hardware-in-the-loop simulation system,a simplified quasi-dimensional model for diesel engine working process was proposed,which was based on the phase-divided spray mixing model.The software MATLAB/Simulink was utilized to simulate diesel engine performance parameters.The comparisons between calculated results and experimental data show that the relative error of power and brake specific fuel consumption is less than 2.8%,and the relative error of nitric oxide and soot emissions is less than 9.1%.At the same time,the average computational time for simulation of one working process with the new model is 36 s,which presents good real time operating performance of the model.The simulation results also indicate that the nozzle flow coefficient has great influence on the prediction precision of performance parameters in diesel engine simulation model. 展开更多
关键词 diesel engine phase-divided spray mixing model quasi-dimensional model MATLAB/SIMULINK prediction precision
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Impacts of salinity parameterizations on temperature simulation over and in a hypersaline lake 被引量:2
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作者 文莉娟 NAGABHATLA Nidhi +2 位作者 赵林 李照国 陈世强 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2015年第3期790-801,共12页
In this paper,we introduced parameterizations of the salinity effects(on heat capacity,thermal conductivity,freezing point and saturated vapor pressure) in a lake scheme integrated in the Weather Research and Forecast... In this paper,we introduced parameterizations of the salinity effects(on heat capacity,thermal conductivity,freezing point and saturated vapor pressure) in a lake scheme integrated in the Weather Research and Forecasting model coupled with the Community Land Model(WRF-CLM). This was done to improve temperature simulation over and in a saline lake and to test the contributions of salinity effects on various water properties via sensitivity experiments. The modified lake scheme consists of the lake module in the CLM model,which is the land component of the WRF-CLM model. The Great Salt Lake(GSL) in the USA was selected as the study area. The simulation was performed from September 3,2001 to September 30,2002. Our results show that the modif ied WRF-CLM model that includes the lake scheme considering salinity effects can reasonably simulate temperature over and in the GSL. This model had much greater accuracy than neglecting salinity effects,particularly in a very cold event when that effect alters the freezing point. The salinity effect on saturated vapor pressure can reduce latent heat flux over the lake and make it slightly warmer. The salinity effect on heat capacity can also make lake temperature prone to changes. However,the salinity effect on thermal conductivity was found insignificant in our simulations. 展开更多
关键词 temperature simulation salinity parameterizations WRF-CLM Great Salt Lake
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Modeling and Simulation of Hydraulic Long Transmission Line by Bond Graph
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作者 Dragan Prsie Novak Nedie Ljubisa Dubonjie 《Journal of Mechanics Engineering and Automation》 2013年第4期257-262,共6页
This paper addresses the issue of modeling of the hydraulic long transmission line. In its base, such model is nonlinear with distributed parameters. Since general solution in closed-form for such model in time-domain... This paper addresses the issue of modeling of the hydraulic long transmission line. In its base, such model is nonlinear with distributed parameters. Since general solution in closed-form for such model in time-domain is not available, certain simplifications have to be introduced. The pipeline in the paper has been divided to a cascaded network of n segments so that a model with lumped parameters could be reached. For segment modeling, a standard library of bond graphs element has been used. On the basis of models with lumped parameters, the effect of the number of segments, pipeline length and effective bulk modulus on the dynamics of long transmission line have been analyzed. 展开更多
关键词 Long transmission line lumped parameters n segments bond graph
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Influences of Amazonian White and Black Waters on the Hematological and Biochemical Plasma Features of Arapaima gigas (Osteoglossiformes)
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作者 Cleverson Agner Ramos Jose Carlos Nunes Raulino +5 位作者 Glauber Cruz de Menezes Iracimar Batista do Carmo Elenice Martins Brasil Elizabeth Gusmao Affonso Oscar Tadeu Ferreira da Costa Marisa Narciso Femandes 《Journal of Life Sciences》 2014年第3期252-261,共10页
The Arapaima gigas, despite being an air breather, its gill structure is quite close to water breathers, especially in early stages of development. The effects of Amazonian waters is well notices in other Teleostei ex... The Arapaima gigas, despite being an air breather, its gill structure is quite close to water breathers, especially in early stages of development. The effects of Amazonian waters is well notices in other Teleostei expose to BW (black water), and WW (white water). However, information about hematological adjustments and its implications to ionic regulation patters are scarce. Therefore, our aim was to analyzed A. gigas hematological parameters when exposed to BW and WW providing suitable hematological data concerning about physiological responses in Amazonian waters. Fish were acclimated in three separated ponds containing BW, WW and well water as control (C). Blood samples were taken from the caudal vessel in order to perform measurement assays on levels of hemoglobin, hematocrit, mean corpuscular volume, corpuscular hemoglobin, corpuscular hemoglobin concentration, glucose, cholesterol and protein. Our findings corroborate the hypothesis stating that BW does interfere on fish adaptation specialy in smallfish (-100 g). However in largefish (-1,000 g) neither WW or BW can interfere on plasma profile of analysed fish. Despite black water systems being considered a barrier constraining the dispersion of several species, this seems not to be a problem for this specie which has kept its ion-regulatory mechanisms even in black waters. 展开更多
关键词 Amazon fish blood parameters Amazonian waters Pirarucu.
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Simulation of Spin-3/2 Blume-Capel Model on a Cellular Automaton with Heating and Cooling Algorithm
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作者 N.Seferoglu 《Communications in Theoretical Physics》 SCIE CAS CSCD 2011年第7期168-172,共5页
The spin-3/2 B1ume-Capel model is studied using the heating and cooling algorithms improved from the Creutz cellular automaton (CCA). The calculations are done on various sizes of the simple cubic lattice in the 0 ... The spin-3/2 B1ume-Capel model is studied using the heating and cooling algorithms improved from the Creutz cellular automaton (CCA). The calculations are done on various sizes of the simple cubic lattice in the 0 ≤ D/J ≤ 5 parameter region. The phase diagram of the model and temperature variation of the thermodynamic quantities are obtained. We confirm the existence of a critical end point within the heating calculations. However, in contrast to the heating calculations, we do not obtain the first-order line at low temperature with cooling algorithm calculations. The results are compared with those of other theories. 展开更多
关键词 spin-3/2 Blume-Capel model cellular automaton simple cubic lattice
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Design of increasing controllability of braking vehicle
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作者 Talkachou Dzianis 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2016年第3期272-278,共7页
The operating principle of an antilock braking system (ABS) is it compares current value of angular acceleration with the threshold value. The advantage of such system is that enough it has only the angular velocity... The operating principle of an antilock braking system (ABS) is it compares current value of angular acceleration with the threshold value. The advantage of such system is that enough it has only the angular velocity sensors. The disadvantage is successive overshoot, i. e. successive transition from wheels locking mode to wheels rolling mode. So braking mechanism can’ t realize the maximum possible torque in the current road conditions. The idea of increasing the braking effectiveness is the intensity of rising pressure depends on the road conditions. The problem is the torque produced by braking mechanism, current road conditions and the value of traction coefficient is unknown For evaluation of these parameters built and training three neural networks. A simulator of random road condition's variation was built to test adequacy of the control unites operation in close to real conditions. 展开更多
关键词 antilock braking system (ABS) model of braking vehicle parameter identification simulation experiment
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Parameter matching of hydraulic balancing circuit based on AMESim
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作者 HE Ningning ZHANG Ping +1 位作者 ZHANG Sen SUN Tianyu 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2022年第4期493-500,共8页
In order to improve the stability of the hydraulic balancing circuit,taking a certain type of vehicular radar flip device as the research object,the influence of different wind load,counterbalance valve parameters and... In order to improve the stability of the hydraulic balancing circuit,taking a certain type of vehicular radar flip device as the research object,the influence of different wind load,counterbalance valve parameters and hydraulic pump flow pulsation on the system flip process are simulated and analyzed.Through the force analysis of the flipping device,the total load curve of the flip cylinder is obtained by using MATLAB simulation.The simulation model of balancing circuit and plane flip device are built by AMESim software,and the reasonable parameter matching relationship is obtained by specific simulation analysis.The simulation results show that when the wind load is to the left and decreases,the system runs more stably.When wind load works in the right direction,the load on the piston rod of the hydraulic cylinder decreases but the jitter amplitude increases.At the same time,the stability of the balancing circuit can be effectively improved by properly reducing the damping diameter of the counterbalance valve,setting the pilot ratio to 4∶1 and using the hydraulic pump with small pulsation.The optimized parameter matching relationship can not only meet the requirements of typical system conditions and responses,but also improve the performance of the circuit. 展开更多
关键词 balancing circuit parameter matching AMESIM counterbalance valve SIMULATION
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The research analysis of aerodynamic numerical simulation of grid fin
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作者 武频 马勇刚 陈纯 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2005年第7期741-746,共6页
This paper presents the results of an investigation to use arc-length mesh generation and finite volume TVD scheme to calculate Euler equations for predicting the effect of geometry parameters in reducing the drag for... This paper presents the results of an investigation to use arc-length mesh generation and finite volume TVD scheme to calculate Euler equations for predicting the effect of geometry parameters in reducing the drag force and improving the lift-drag ratio of grid fin in the supersonic flow regime. The effects of frame and web, whose cross section shape and thickness and spacing,on the aerodynamic character of the grid fin were studied. Calculations were made at Mach 2.5 and several angles of attack. The results were validated by comparing the computed aerodynamic coefficients against wind tunnel experimental data. Good agreement was found between computed and experimental results. The computed results suggest that parameters of the grid fin's frame have the greatest effect on the grid fin aerodynamic character, especially on its drag force. It was concluded proper choice of appropriate grid fin geometry parameters could reduce the drag force and improve the lift-drag ratios. 展开更多
关键词 Grid fin Aerodynamic character Numerical simulation
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Ocean Mixing with Lead-Dependent Subgrid Scale Brine Rejection Parameterization in a Climate Model 被引量:1
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作者 Meibing Jin Jennifer Hutchings +1 位作者 Yusuke Kawaguchi Takashi Kikuchi 《Journal of Ocean University of China》 SCIE CAS 2012年第4期473-480,共8页
Sea ice thickness is highly spatially variable and can cause uneven ocean heat and salt flux on subgrid scales in climate models.Previous studies have demonstrated improvements in ocean mixing simulation using paramet... Sea ice thickness is highly spatially variable and can cause uneven ocean heat and salt flux on subgrid scales in climate models.Previous studies have demonstrated improvements in ocean mixing simulation using parameterization schemes that distribute brine rejection directly in the upper ocean mixed layer.In this study,idealized ocean model experiments were conducted to examine modeled ocean mixing errors as a function of the lead fraction in a climate model grid.When the lead is resolved by the grid,the added salt at the sea surface will sink to the base of the mixed layer and then spread horizontally.When averaged at a climate-model grid size,this vertical distribution of added salt is lead-fraction dependent.When the lead is unresolved,the model errors were systematic leading to greater surface salinity and deeper mixed-layer depth(MLD).An empirical function was developed to revise the added-salt-related parameter n from being fixed to lead-fraction dependent.Application of this new scheme in a climate model showed significant improvement in modeled wintertime salinity and MLD as compared to series of CTD data sets in 1997/1998 and 2006/2007.The results showed the most evident improvement in modeled MLD in the Arctic Basin,similar to that using a fixed n=5,as recommended by the previous Arctic regional model study,in which the parameter n obtained is close to 5 due to the small lead fraction in the Arctic Basin in winter. 展开更多
关键词 climate model sea ice brine rejection ocean mixing PARAMETERIZATION
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Simulation and formability analysis of drawing process for automotive B-pillar
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作者 邢忠文 方华松 包军 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2009年第2期209-212,共4页
The numerical simulation on drawing process of automotive B-pillar was carried out on AutoForm software,and dangerous forming areas were discovered.The processing parameters,such as the layout of drawbeads,blank holdi... The numerical simulation on drawing process of automotive B-pillar was carried out on AutoForm software,and dangerous forming areas were discovered.The processing parameters,such as the layout of drawbeads,blank holding force and the shape of blank,were adjusted and optimized according to the simulation results.Results indicate that the quality defects can be forecast and removed,which improves the stability of forming process.The cost of design is decreased and the research cycle is shortened.It is proved that the drawing process and die design of B-pillar forming are feasible in actual production. 展开更多
关键词 draw forming simulation orocessing parameter automotive B-nillar
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