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A New Class of Efficient Schemes for the Cahn-Hilliard-Navier-Stokes Equations
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作者 WANG Lijing WANG Danxia ZHANG Jianwen 《应用数学》 北大核心 2025年第3期607-624,共18页
In this paper,we construct a new class of efficient and high-order schemes for the Cahn-Hilliard-Navier-Stokes equations with periodic boundary conditions.These schemes are based on two types of scalar auxiliary varia... In this paper,we construct a new class of efficient and high-order schemes for the Cahn-Hilliard-Navier-Stokes equations with periodic boundary conditions.These schemes are based on two types of scalar auxiliary variable approaches.By using a new pressure correction method,the accuracy of the pressure has been greatly improved.Furthermore,one only needs to solve a series of fully decoupled linear equations with constant coefficients at each time step.In addition,we prove the unconditional energy stability of the schemes,rigorously.Finally,plenty of numerical simulations are carried out to verify the convergence rates,stability,and effectiveness of the proposed schemes numerically. 展开更多
关键词 Cahn-Hilliard-Navier-Stokes equation Scalar auxiliary variable Pressurecorrection Unconditional energy stability
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協定职业学校课程標准 被引量:2
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《教育与职业》 1924年第0期137-137,共1页
全国教育会联合会组织委员会.续订新学制师范及职业科课程标准.其职业部分.邀与本社合作.经公推朱经农秉文.王企华.黄伯樵.赵师復.杨玉诸君代表本社.加入讨论.举办女子职业学校.业已呈准丹徒县立案.不日移交.其经费由李耆卿君商得齐抚... 全国教育会联合会组织委员会.续订新学制师范及职业科课程标准.其职业部分.邀与本社合作.经公推朱经农秉文.王企华.黄伯樵.赵师復.杨玉诸君代表本社.加入讨论.举办女子职业学校.业已呈准丹徒县立案.不日移交.其经费由李耆卿君商得齐抚万督军慨允)助. 展开更多
关键词 黄伯樵 学校 程標 秉文
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Design of logic process based low-power 512-bit EEPROM for UHF RFID tag chip 被引量:2
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作者 金丽妍 LEE J H KIM Y H 《Journal of Central South University》 SCIE EI CAS 2010年第5期1011-1020,共10页
A 512-bit EEPROM IP was designed by using just logic process based devices.To limit the voltages of the devices within 5.5 V,EEPROM core circuits,control gate(CG) and tunnel gate(TG) driving circuits,DC-DC converters:... A 512-bit EEPROM IP was designed by using just logic process based devices.To limit the voltages of the devices within 5.5 V,EEPROM core circuits,control gate(CG) and tunnel gate(TG) driving circuits,DC-DC converters:positive pumping voltage(VPP=4.75 V) ,negative pumping voltage(VNN=4.75 V) ,and VNNL(=VNN/2) generation circuit were proposed.In addition,switching powers CG high voltage(CG_HV) ,CG low voltage(CG_LV) ,TG high voltage(TG_HV) ,TG low voltage(TG_LV) ,VNNL_CG and VNNL_TG switching circuit were supplied for the CG and TG driving circuit.Furthermore,a sequential pumping scheme and a new ring oscillator with a dual oscillation period were proposed.To reduce a power consumption of EEPROM in the write mode,the reference voltages VREF_VPP for VPP and VREE_VNN for VNN were used by dividing VDD(1.2 V) supply voltage supplied from the analog block in stead of removing the reference voltage generators.A voltage level detector using a capacitive divider as a low-power DC-DC converter design technique was proposed.The result shows that the power dissipation is 0.34μW in the read mode,13.76μW in the program mode,and 13.66μW in the erase mode. 展开更多
关键词 electrically erasable programmable read-only memory (EEPROM) logic process DC-DC converter ring oscillator sequential pumping scheme dual oscillation period radio frequency identification (RFID)
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Design of 512-bit logic process-based single poly EEPROM IP
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作者 金丽妍 JANG Ji-Hye +2 位作者 余忆宁 HA Pan-Bong KIM Young-Hee 《Journal of Central South University》 SCIE EI CAS 2011年第6期2036-2044,共9页
A single poly EEPROM cell circuit sharing the deep N-well of a cell array was designed using the logic process. The proposed cell is written by the FN tunneling scheme and the cell size is 41.26 μm2, about 37% smalle... A single poly EEPROM cell circuit sharing the deep N-well of a cell array was designed using the logic process. The proposed cell is written by the FN tunneling scheme and the cell size is 41.26 μm2, about 37% smaller than the conventional cell. Also, a small-area and low-power 512-bit EEPROM IP was designed using the proposed cells which was used for a 900 MHz passive UHF RFID tag chip. To secure the operation of the cell proposed with 3.3 V devices and the reliability of the used devices, an EEPROM core circuit and a DC-DC converter were proposed. Simulation results for the designed EEPROM IP based on the 0.18μm logic process show that the power consumptions in read mode, program mode and erase mode are 11.82, 25.15, and 24.08 ~tW, respectively, and the EEPROM size is 0.12 mm2. 展开更多
关键词 single poly EEPROM cell Fowler-Nordheim tunneling logic process radio frequency identification small area
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An adaptive waveform-detection threshold joint optimization method for target tracking 被引量:5
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作者 王宏强 夏洪恩 +1 位作者 程永强 王璐璐 《Journal of Central South University》 SCIE EI CAS 2013年第11期3057-3064,共8页
The joint optimization of detection threshold and waveform parameters for target tracking which comes from the idea of cognitive radar is investigated for the modified probabilistic data association(MPDA)filter.The tr... The joint optimization of detection threshold and waveform parameters for target tracking which comes from the idea of cognitive radar is investigated for the modified probabilistic data association(MPDA)filter.The transmitted waveforms and detection threshold are adaptively selected to enhance the tracking performance.The modified Riccati equation is adopted to predict the error covariance which is used as the criterion function,while the optimization problem is solved through the genetic algorithm(GA).The detection probability,false alarm probability and measurement noise covariance are all considered together,which significantly improves the tracking performance of the joint detection and tracking system.Simulation results show that the proposed adaptive waveform-detection threshold joint optimization method outperforms the adaptive threshold method and the fixed parameters method,which will reduce the tracking error.The average reduction of range error between the adaptive joint method and the fixed parameters method is about 0.6 m,while that between the adaptive joint method and the adaptive threshold only method is about 0.3 m.Similar error reduction occurs for the velocity error and acceleration error. 展开更多
关键词 cognitive radar adaptive waveform selection target tracking joint optimization detection-tracking system
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Zonal disintegration mechanism of isotropic rock masses around a deep spherical tunnel
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作者 谷新保 毕靖 许明 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第10期4074-4082,共9页
In order to investigate zonal disintegration mechanism of isotropic rock masses around a deep spherical tunnel, a new mechanical model subjected to dynamic unloading under hydrostatic pressure condition is proposed. T... In order to investigate zonal disintegration mechanism of isotropic rock masses around a deep spherical tunnel, a new mechanical model subjected to dynamic unloading under hydrostatic pressure condition is proposed. The total elastic stress-field distributions is determined using the elastodynamic equation. The effects of unloading rate and dynamic mechanical parameters of isotropic deep rock masses on the zonal disintegration phenomenon of the surrounding rock masses around a deep spherical tunnel as well as the total elastic stress field distributions are considered. The number and size of fractured and non-fractured zones are determined by using the Hoek-Brown criterion. Numerical computation is carried out. It is found from numerical results that the number of fractured zones increases with increasing the disturbance coefficient, in-situ stress, unloading time and unloading rate, and it decreases with increasing parameter geological strength index, the strength parameter and the uniaxial compressive strength of intact rock. 展开更多
关键词 zonal disintegration mechanism isotropic rock mass spherical tunnel dynamic unloading
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A coarse-grained differentiated routing algorithm in multi-protocol label switching traffic engineering
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作者 杜荔 于军相 王晓静 《Journal of Central South University》 SCIE EI CAS 2010年第6期1258-1263,共6页
A new coarse-grained differentiated least interference routing algorithm(CDLI) with DiffServ-Aware was presented.This algorithm is composed of off-line and on-line stages,taking into account both real-time traffic and... A new coarse-grained differentiated least interference routing algorithm(CDLI) with DiffServ-Aware was presented.This algorithm is composed of off-line and on-line stages,taking into account both real-time traffic and best-effort traffic.Off-line stage is to determine the shortest path set disjointed path(DP) database for real-time traffic,and to identify link critical value by traffic profile information of real-time traffic and DP database.On-line stage is at first to select route in the DP database for real-time traffic,if there is no path to meet the needs,the dynamic routing will be operated.On-line routing algorithm chooses the relatively short path for real-time traffic to meet their bandwidth requirements,and for best-effort traffic it chooses a lighter load path.The simulation results show that compared with the dynamic online routing algorithm(DORA) and constrained shortest path first(CSPF) algorithm,the new algorithm can significantly improve network throughput and reduce the average path length of real-time traffic.This guarantees quality of service(QoS) of real-time traffic while improving the utilization of network resources. 展开更多
关键词 multi-protocol label switching (MPLS) traffic engineering constraint-based routing explicit routing
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Multi-objective optimization based optimal setting control for industrial double-stream alumina digestion process 被引量:1
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作者 WANG Xiao-li LU Mei-yu +1 位作者 WEI Si-mi XIE Yong-fang 《Journal of Central South University》 SCIE EI CAS CSCD 2022年第1期173-185,共13页
The operation variables,including feed rate of ore slurry,caustic solution and live steams in the double-stream alumina digestion process,determine the product quality,process costs and the environment pollution.Previ... The operation variables,including feed rate of ore slurry,caustic solution and live steams in the double-stream alumina digestion process,determine the product quality,process costs and the environment pollution.Previously,they were set by the technical workers according to the offline analysis results and an empirical formula,which leads to unstable process indices and high consumption frequently.So,a multi-objective optimization model is built to maintain the balance between resource consumptions and process indices by taking technical indices and energy efficiency as objectives,where the key technical indices are predicted based on the digestion kinetics of diaspore.A multi-objective state transition algorithm(MOSTA)is improved to solve the problem,in which a self-adaptive strategy is applied to dynamically adjust the operator factors of the MOSTA and dynamic infeasible threshold is used to handle constraints to enhance searching efficiency and ability of the algorithm.Then a rule based strategy is designed to make the final decision from the Pareto frontiers.The method is integrated into an optimal control system for the industrial digestion process and tested in the actual production.Results show that the proposed method can achieve the technical target while reducing the energy consumption. 展开更多
关键词 double-stream digestion process optimal setting control multi-objective optimization state transition algorithm rule based decision making
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Target reliability index for serviceability limit state of single piles 被引量:4
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作者 边晓亚 郑俊杰 +1 位作者 徐志军 章荣军 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第1期310-316,共7页
The objective is to develop an approach for the determination of the target reliability index for serviceability limit state(SLS) of single piles. This contributes to conducting the SLS reliability-based design(RBD) o... The objective is to develop an approach for the determination of the target reliability index for serviceability limit state(SLS) of single piles. This contributes to conducting the SLS reliability-based design(RBD) of piles. Based on a two-parameter,hyperbolic curve-fitting equation describing the load-settlement relation of piles, the SLS model factor is defined. Then, taking into account the uncertainties of load-settlement model, load and bearing capacity of piles, the formula for computing the SLS reliability index(βsls) is obtained using the mean value first order second moment(MVFOSM) method. Meanwhile, the limit state function for conducting the SLS reliability analysis by the Monte Carlo simulation(MCS) method is established. These two methods are finally applied to determine the SLS target reliability index. Herein, the limiting tolerable settlement(slt) is treated as a random variable. For illustration, four load test databases from South Africa are compiled again to conduct reliability analysis and present the recommended target reliability indices. The results indicate that the MVFOSM method overestimates βsls compared to that computed by the MCS method. Besides, both factor of safety(FS) and slt are key factors influencing βsls, so the combination of FS and βsls is welcome to be used for the SLS reliability analysis of piles when slt is determined. For smaller slt, pile types and soils conditions have significant influence on the SLS target reliability indices; for larger slt, slt is the major factor having influence on the SLS target reliability indices. This proves that slt is the most key parameter for the determination of the SLS target reliability index. 展开更多
关键词 single pile serviceability limit state target reliability index mean value first order second moment method Monte Carlo simulation
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A new method of characterizing equivalent strain for equal channel angular processing 被引量:1
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作者 赵军 王振华 +3 位作者 孙淑华 赵德利 任利国 傅万堂 《Journal of Central South University》 SCIE EI CAS 2009年第3期349-353,共5页
In order to establish the quantitative relationship between equivalent strain and the performance index of the deformed material within the range of certain passes for equal channel angular processing (ECAP), a new ... In order to establish the quantitative relationship between equivalent strain and the performance index of the deformed material within the range of certain passes for equal channel angular processing (ECAP), a new approach to characterize the equivalent strain was proposed. The results show that there exists better accordance between mechanical property (such as hardness or strength) and equivalent strain after rolling and ECAP in a certain range of deformation amount, and Gauss equation can be satisfied among the equivalent strain and the mechanical properties for ECAP. Through regression analysis on the data of hardness and strength after the deformation, a more generalized expression of equivalent strain for ECAP is proposed as:ε=k0exp[-(k1M-k2)^2], where M is the strength or hardness of the material, k1 is the modified coefficient (k1∈ (0, 1)), ko and k2 are two parameters dependent on the critical strain and mechanical property that reaches saturation state for the material, respectively. In this expression the equivalent strain for ECAP is characterized novelly through the mechanical parameter relating to material property rather than the classical geometry equation. 展开更多
关键词 equal channel angular processing (ECAP) equivalent strain mechanical property characterizing method
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Impact coefficient and reliability of mid-span continuous beam bridge under action of extra heavy vehicle with low speed 被引量:13
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作者 刘波 王有志 +1 位作者 胡朋 袁泉 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第4期1510-1520,共11页
To analyze the dynamic response and reliability of a continuous beam bridge under the action of an extra heavy vehicle, a vehicle–bridge coupled vibration model was established based on the virtual work principle and... To analyze the dynamic response and reliability of a continuous beam bridge under the action of an extra heavy vehicle, a vehicle–bridge coupled vibration model was established based on the virtual work principle and vehicle–bridge displacement compatibility equation, which can accurately simulate the dynamic characteristics of the vehicle and bridge. Results show that deck roughness has an important function in the effect of the vehicle on the bridge. When an extra heavy vehicle passes through the continuous beam bridge at a low speed of 5 km/h, the impact coefficient reaches a high value, which should not be disregarded in bridge safety assessments. Considering that no specific law exists between the impact coefficient and vehicle speed, vehicle speed should not be unduly limited and deck roughness repairing should be paid considerable attention. Deck roughness has a significant influence on the reliability index, which decreases as deck roughness increases. For the continuous beam bridge in this work, the reliability index of each control section is greater than the minimum reliability index. No reinforcement measures are required for over-sized transport. 展开更多
关键词 continuous beam bridge extra heavy vehicle coupled vibration impact coefficient reliability
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Multi-objective optimization of rolling schedule based on cost function for tandem cold mill 被引量:4
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作者 陈树宗 张欣 +3 位作者 彭良贵 张殿华 孙杰 刘印忠 《Journal of Central South University》 SCIE EI CAS 2014年第5期1733-1740,共8页
In terms of tandem cold mill productivity and product quality, a multi-objective optimization model of rolling schedule based on cost fimction was proposed to determine the stand reductions, inter-stand tensions and r... In terms of tandem cold mill productivity and product quality, a multi-objective optimization model of rolling schedule based on cost fimction was proposed to determine the stand reductions, inter-stand tensions and rolling speeds for a specified product. The proposed schedule optimization model consists of several single cost fi.mctions, which take rolling force, motor power, inter-stand tension and stand reduction into consideration. The cost function, which can evaluate how far the rolling parameters are from the ideal values, was minimized using the Nelder-Mead simplex method. The proposed rolling schedule optimization method has been applied successfully to the 5-stand tandem cold mill in Tangsteel, and the results from a case study show that the proposed method is superior to those based on empirical formulae. 展开更多
关键词 tandem cold mill multi-object optimization rolling schedule cost function simplex algorithm
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Automatic salient object segmentation using saliency map and color segmentation 被引量:1
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作者 HAN Sung-ho JUNG Gye-dong +2 位作者 LEE Sangh-yuk HONG Yeong-pyo LEE Sang-hun 《Journal of Central South University》 SCIE EI CAS 2013年第9期2407-2413,共7页
A new method for automatic salient object segmentation is presented.Salient object segmentation is an important research area in the field of object recognition,image retrieval,image editing,scene reconstruction,and 2... A new method for automatic salient object segmentation is presented.Salient object segmentation is an important research area in the field of object recognition,image retrieval,image editing,scene reconstruction,and 2D/3D conversion.In this work,salient object segmentation is performed using saliency map and color segmentation.Edge,color and intensity feature are extracted from mean shift segmentation(MSS)image,and saliency map is created using these features.First average saliency per segment image is calculated using the color information from MSS image and generated saliency map.Then,second average saliency per segment image is calculated by applying same procedure for the first image to the thresholding,labeling,and hole-filling applied image.Thresholding,labeling and hole-filling are applied to the mean image of the generated two images to get the final salient object segmentation.The effectiveness of proposed method is proved by showing 80%,89%and 80%of precision,recall and F-measure values from the generated salient object segmentation image and ground truth image. 展开更多
关键词 salient object visual attention saliency map color segmentation
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Two Efficient Numerical Algorithms for the Thermally Coupled Incompressible MHD Equations
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作者 LIAO Mingliang WANG Danxia 《应用数学》 2025年第4期932-951,共20页
In this work,we construct two efficient fully decoupled,linear,unconditionally stable numerical algorithms for the thermally coupled incompressible magnetohydrodynamic equations.Firstly,in order to obtain the desired ... In this work,we construct two efficient fully decoupled,linear,unconditionally stable numerical algorithms for the thermally coupled incompressible magnetohydrodynamic equations.Firstly,in order to obtain the desired algorithm,we introduce a scalar auxiliary variable(SAV)to get a new equivalent system.Secondly,by combining the pressure-correction method and the explicit-implicit method,we perform semi-discrete numerical algorithms of first and second order,respectively.Then,we prove that the obtained algorithms follow an unconditionally stable law in energy,and we provide a detailed implementation process,which we only need to solve a series of linear differential equations with constant coefficients at each time step.More importantly,with some powerful analysis,we give the order of convergence of the errors.Finally,to illustrate theoretical results,some numerical experiments are given. 展开更多
关键词 Magnetohydrodynamic equation Fully decoupled Unconditionally stability Scalar auxiliary variable Error analysis
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