期刊文献+
共找到31,126篇文章
< 1 2 250 >
每页显示 20 50 100
The height-width ratio limited value for rubber bearing isolated structure computed by uniform design method 被引量:7
1
作者 王铁英 王焕定 +1 位作者 张永山 刘文光 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2007年第1期36-40,共5页
Rubber isolation is the most mature control technology in practical application, and is widely used by short rigid buildings. However, many high isolation buildings have been built around the world in recent years, wh... Rubber isolation is the most mature control technology in practical application, and is widely used by short rigid buildings. However, many high isolation buildings have been built around the world in recent years, which do not follow the existing criterions and codes. Many researchers began to research the special problems caused by larger height-width ratio isolation structures. The overturning effect of high height-width ratio structures with rubber bearing is firstly studied. Considering the main factors, such as the height-width ratio of structures, type of site, the designed basic acceleration of ground motion and the decouple factor in horizon, computing experiment is defined with the Uniform Design Method, which is also known as designing isolation structure. The forces of the bearing under edge of structures based on the position of the rubber bearing are calculated. The result indicates that the rubber bearings will lose its functionality under very high tension and compressing force of earthquake motion in horizon and vertical, when the height-width ratio is over a certain value. Thus, based on the calculation result of isolation structures defined in the uniform design method, regression analysis is conducted, and also the rubber edge force regression formula are gotten, which has higher correlation and smaller standard deviation. This formula can be used to roughly calculate whether the pull force occurs at the edge of the building. By the edge bearings of isolation structure minimum force formula, the height-width ratio limited value of the isolation structure is deducted when rubber bearing has minimum force of zero. 展开更多
关键词 隔离结构 建筑结构 工程设计 非线性动力分析
下载PDF
Investigation of paeonol-geniposide on acute alcoholic liver injury based on uniform design method
2
作者 LIU Ke LIU Yu-long +3 位作者 SUN Min LIU Ling-ling ZHANG Lu-ning YAN Gui-ming 《Journal of Hainan Medical University》 2022年第24期25-31,共7页
Objective:To explore the optimal ratio and compatibility effect of paeonol-geniposide combination on acute alcoholic liver injury by uniform design.Methods:Lieber-DeCarli alcoholic liquid feed was used to induce acute... Objective:To explore the optimal ratio and compatibility effect of paeonol-geniposide combination on acute alcoholic liver injury by uniform design.Methods:Lieber-DeCarli alcoholic liquid feed was used to induce acute alcoholic liver injury in mice.Uniform design was used to select the best dosage combination of paeonol and geniposide,and the related indexes of liver injury and oxidative stress were detected by kit.Serum inflammatory factors were detected by ELISA,and the expressions of p38 MAPK,JNK and NF-κB P65 related proteins in liver were detected by Western-blot.Results:The regression equation suggested that paeonol:geniposide=220:20 was the best ratio of paeonol and geniposide to resist alcoholic liver injury.Compared with the model group,the liver injury indexes and oxidation products of the paeonol+geniposide group decreased significantly,the antioxidant activity of liver tissue increased significantly,and the expression levels of p-p38 MAPK,p-JNK and NF-κB P65 protein decreased significantly.Conclusion:The optimal dosage of paeonolgeniposide was effectively optimized by uniform design and pharmacodynamic analysis.The combination of the two drugs could reduce the alcoholic liver injury by reducing the oxidative stress injury and inflammatory response in the liver tissue of mice,and its effect might be related to the targeting of p38 MAPK/JNK/NF-κB channel. 展开更多
关键词 PAEONOL GENIPOSIDE Alcoholic liver injury uniform design Chinese medicine effective ingredient ratio
下载PDF
A study of arc stability of basic electrode in view of uniform design method
3
作者 孟工戈 金龙浩 杨拓宇 《China Welding》 EI CAS 2007年第3期32-35,共4页
In order to develop a basic electrode with low fume and good usability, a new slag system has been designed after analyzing several basic electrode slag systems. Then in view of uniform design method, arranging the ex... In order to develop a basic electrode with low fume and good usability, a new slag system has been designed after analyzing several basic electrode slag systems. Then in view of uniform design method, arranging the experiment points by it, the influenced laws of the new system coating components on the arc stability had been searched. In the formula, nine coating components were taken as independent variables and they were divided into six levels in all twenty-four experiments. The arc stability was taken as function and taken down the data when welding and then put them into the computer to be processed statistically. The analysis results give the mathematical model and trend diagrams between independent variables and the function. They indicate that the effects of many coating components on the arc stability are in the mutual form. The mutual effects between CaCO3 and BaF2, BaF2 and BaCO3, increases the arc stability separately. While the mutual effects between CaF2 and iron powder, the square item of iron powder itself decreases the arc stability separately. 展开更多
关键词 基本电极 电弧 稳定性 设计
下载PDF
To improve robustness of mechanical properties of semi-solid cast A356 alloy using taguchi design method
4
作者 Yi-wu Xu Hong-yi Zhan +4 位作者 Wei Tong Jin-ping Li Le-peng Zhang De-jiang Li Xiao-qin Zeng 《China Foundry》 SCIE EI CAS CSCD 2024年第2期175-184,共10页
Mechanical properties of semi-solid casting are dependent on multiple processing parameters,and improper processing parameters will not only reduce mean data but also increase variations.The present study investigated... Mechanical properties of semi-solid casting are dependent on multiple processing parameters,and improper processing parameters will not only reduce mean data but also increase variations.The present study investigated the impact of parameters in slurry preparation and heat treatment on the yield strength and ductility of T6 heat-treated A356 Al-Si alloy using rapid slurry forming(RSF)semi-solid casting.The focus was primarily on the robustness of mechanical properties based on Taguchi design method.By analyzing signal-to-noise ratio and minimum value calculated from-3S,the optimum slurry preparation parameters and heat treatment parameters were determined to be no quench,enthalpy exchange material(EEM)temperature of 140℃,EEM-to-melt ratio of 6mass%,stirring time of 18 s,solution heat treated at 520℃ for 2 h,and ageing heat treated at 190℃ for 6 h.In a small batch validation,the-3S yield strength and-3S elongation reach 256.1 MPa and 5.03% respectively,showing a satisfactory robustness.The hardness and microstructure of heat-treated samples with the best and worst properties were characterized to gain insight into the underlying mechanisms affecting the mean value and variations of mechanical properties. 展开更多
关键词 semi-solid casting taguchi design method signal-to-noise ratio mechanical property MICROSTRUCTURE
下载PDF
A Mixed-Variable Experimental Design Method
5
作者 Zili Wan Qi Wang 《Open Journal of Applied Sciences》 2024年第2期343-352,共10页
Mixed-variable problems are inevitable in engineering. However, few researches pay attention to discrete variables. This paper proposed a mixed-variable experimental design method (ODCD): first, the design variables w... Mixed-variable problems are inevitable in engineering. However, few researches pay attention to discrete variables. This paper proposed a mixed-variable experimental design method (ODCD): first, the design variables were divided into discrete variables and continuous variables;then, the DVD method was employed for handling discrete variables, the LHD method was applied for continuous variables, and finally, a Columnwise-Pairwise Algorithm was used for the overall optimization of the design matrix. Experimental results demonstrated that the ODCD method outperforms in terms of the sample space coverage performance. 展开更多
关键词 OPTIMIZATION Experimental design methods Discrete Variable
下载PDF
Exploring Digital Visualization Methods in Urban Public Building Space Design
6
作者 Pan Liang Sharul Azim Sharudin 《Journal of Architectural Research and Development》 2024年第2期55-61,共7页
Digital technology has driven the innovation of architectural design methods and tools,applying digital techniques to allow greater possibilities for more innovative and scientific design of public building spaces.Thi... Digital technology has driven the innovation of architectural design methods and tools,applying digital techniques to allow greater possibilities for more innovative and scientific design of public building spaces.This article first analyzes the characteristics of digital visualization and its advantages in the design of urban public building spaces,including aspects such as visualizing three-dimensional expression,rational analysis of building space,Virtual Reality Experience,and integration of design and construction processes.Subsequently,by introducing digital design methods such as parametric design,algorithmic generation,nonlinear design,and artificial intelligence-assisted design,it explores the methods and implementation approaches of digital visualization in the design of public building spaces.The aim is to offer insights and references for the deeper integration of digital technology into architectural design practices. 展开更多
关键词 Public building Space design Digital visualization methodS
下载PDF
Optimization of H_2O_2 dosage in microwave-H_2O_2 process for sludge pretreatment with uniform design method 被引量:12
7
作者 Qingcong Xiao Hong Yan +3 位作者 Yuansong Wei Yawei Wang Fangang Zeng Xiang Zheng 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2012年第12期2060-2067,共8页
A microwave-H2O2 process for sludge pretreatment exhibited high efficiencies of releasing organics,nitrogen,and phosphorus,but large quantities of H2O2 residues were detected.A uniform design method was thus employed ... A microwave-H2O2 process for sludge pretreatment exhibited high efficiencies of releasing organics,nitrogen,and phosphorus,but large quantities of H2O2 residues were detected.A uniform design method was thus employed in this study to further optimize H2O2 dosage by investigating effects of pH and H2O2 dosage on the amount of H2O2 residue and releases of organics,nitrogen,and phosphorus.A regression model was established with pH and H2O2 dosage as the independent variables,and H2O2 residue and releases of organics,nitrogen,and phosphorus as the dependent variables.In the optimized microwave-H2O2 process,the pH value of the sludge was firstly adjusted to 11.0,then the sludge was heated to 80°C and H2O2 was dosed at a H2O2:mixed liquor suspended solids(MLSS)ratio of 0.2,and the sludge was finally heated to 100°C by microwave irradiation.Compared to the microwave-H2O2 process without optimization,the H2O2 dosage and the utilization rate of H2O2 in the optimized microwave-H2O2 process were reduced by 80% and greatly improved by 3.87 times,respectively,when the H2O2:MLSS dosage ratio was decreased from 1.0 to 0.2,resulting in nearly the same release rate of soluble chemical oxygen demand in the microwave-H2O2 process without optimization at H2O2:MLSS ratio of 0.5. 展开更多
关键词 污泥预处理 微波辐射 H202 均匀设计法 预处理过程 优化 剂量 均匀设计方法
原文传递
Optimizational production of phenyllactic acid by a Lactobacillus buchneri strain via uniform design with overlay sampling methodology 被引量:3
8
作者 Jintao Guan Chaofei Han +3 位作者 Yixin Guan Songhong Zhang Junxian Yun Shanjing Yao 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2019年第2期418-425,共8页
A Lactobacillus buchneri GBS3 strain isolated from the traditional Chinese pickles was used for the production of 3-phenyllactic acid(PLA), an important compound with antimicrobial activities against a wide species of... A Lactobacillus buchneri GBS3 strain isolated from the traditional Chinese pickles was used for the production of 3-phenyllactic acid(PLA), an important compound with antimicrobial activities against a wide species of grampositive and gram-negative bacteria and some fungi. The growth performance of this strain in the de Man, Rogosa and Sharpe(MRS) medium, the production of metabolites of valuable organic acids, and the biosynthesis of PLA using this strain as the whole-cell biocatalyst and phenylpyruvic acid(PPA) as the precursor, were investigated experimentally. The uniform design method with overlay sampling was developed for the optimization of the biotransformation conditions. The results showed that although it produced naturally lactic acid with the maximum concentration of 1.84 g·L^(-1) and PLA with the concentration of 0.015 g·L^(-1) after 66 to 72 h cultivation in MRS broth by fermentation, the present strain displayed an effective utilization ability by transforming PPA to PLA. By the uniform design method with overlay sampling for the design and optimization of transformation conditions, a maximum yield of 10.93 g·L^(-1) PLA with the mole conversion ratio of 83.07% from PPA to PLA was achieved under the optimized condition, i.e., 20 g·L^(-1) glucose, 270 g·L^(-1) cells, 13 g·L^(-1) PPA, pH 8.0 and the reaction time of 15 h, indicating that Lactobacillus buchneri GBS3 was an interesting strain for the biosynthesis of PLA via the microbial transformation. The prediction of PLA yield under different conditions was achieved successfully based on the limited information of only a small number of experiments by the uniform design with overlay sampling. Therefore, the present methodology is effective and helpful for the optimization of the biosynthesis processes of PLA. 展开更多
关键词 Phenyllactic ACID Biotransformati on LACTOBACILLUS Buchneri uniform design OVERLAP Sampling
下载PDF
The Complex System Modeling Method Based on Uniform Design and Neural Network 被引量:1
9
作者 Zhang Yong(Beijing Simulation Center, P.O.Box 142-23, Beijing 100854, P.R. China) 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 1996年第4期27-36,共10页
The Complex System Modeling Method Based on Uniform Design and Neural NetworkZhangYong(BeijingSimulationCent... The Complex System Modeling Method Based on Uniform Design and Neural NetworkZhangYong(BeijingSimulationCenter,P.O.Box142-23,... 展开更多
关键词 MODELING method uniform design NEURAL NETWORK COMPLEX system Simulation.
下载PDF
THE UNIFORM CONVERGENCE OF A DG METHOD FOR A SINGULARLY PERTURBED VOLTERRA INTEGRO-DIFFERENTIAL EQUATION
10
作者 陶霞 谢资清 《Acta Mathematica Scientia》 SCIE CSCD 2023年第5期2159-2178,共20页
The purpose of this work is to implement a discontinuous Galerkin(DG)method with a one-sided flux for a singularly perturbed Volterra integro-differential equation(VIDE)with a smooth kernel.First,the regularity proper... The purpose of this work is to implement a discontinuous Galerkin(DG)method with a one-sided flux for a singularly perturbed Volterra integro-differential equation(VIDE)with a smooth kernel.First,the regularity property and a decomposition of the exact solution of the singularly perturbed VIDE with the initial condition are provided.Then the existence and uniqueness of the DG solution are proven.Then some appropriate projection-type interpolation operators and their corresponding approximation properties are established.Based on the decomposition of the exact solution and the approximation properties of the projection type interpolants,the DG method achieves the uniform convergence in the L2 norm with respect to the singular perturbation parameter e when the space of polynomials with degree p is used.A numerical experiment validates the theoretical results.Furthermore,an ultra-convergence order 2p+1 at the nodes for the one-sided flux,uniform with respect to the singular perturbation parameter e,is observed numerically. 展开更多
关键词 singularly perturbed VIDE DG method Shishkin mesh uniform convergence
下载PDF
Design methods for antimicrobial peptides with improved performance
11
作者 James Mwangi Peter Muiruri Kamau +1 位作者 Rebecca Caroline Thuku Ren Lai 《Zoological Research》 SCIE CSCD 2023年第6期1095-1114,共20页
The recalcitrance of pathogens to traditional antibiotics has made treating and eradicating bacterial infections more difficult.In this regard,developing new antimicrobial agents to combat antibiotic-resistant strains... The recalcitrance of pathogens to traditional antibiotics has made treating and eradicating bacterial infections more difficult.In this regard,developing new antimicrobial agents to combat antibiotic-resistant strains has become a top priority.Antimicrobial peptides(AMPs),a ubiquitous class of naturally occurring compounds with broadspectrum antipathogenic activity,hold significant promise as an effective solution to the current antimicrobial resistance(AMR)crisis.Several AMPs have been identified and evaluated for their therapeutic application,with many already in the drug development pipeline.Their distinct properties,such as high target specificity,potency,and ability to bypass microbial resistance mechanisms,make AMPs a promising alternative to traditional antibiotics.Nonetheless,several challenges,such as high toxicity,lability to proteolytic degradation,low stability,poor pharmacokinetics,and high production costs,continue to hamper their clinical applicability.Therefore,recent research has focused on optimizing the properties of AMPs to improve their performance.By understanding the physicochemical properties of AMPs that correspond to their activity,such as amphipathicity,hydrophobicity,structural conformation,amino acid distribution,and composition,researchers can design AMPs with desired and improved performance.In this review,we highlight some of the key strategies used to optimize the performance of AMPs,including rational design and de novo synthesis.We also discuss the growing role of predictive computational tools,utilizing artificial intelligence and machine learning,in the design and synthesis of highly efficacious lead drug candidates. 展开更多
关键词 Antimicrobial resistance Antimicrobial peptides design methods PEPTIDOMIMETICS Artificial intelligence
下载PDF
Bamboo Fiber Modified Asphalt Mixture Proportion Design and Road Performances Based on Response Surface Method
12
作者 李海滨 SUN Jianmei +3 位作者 WANG Sirui ZHANG Mingming HU Yihong SHENG Yanping 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2023年第1期156-170,共15页
In order to comprehensively utilize the remaining bamboo residue of bamboo products,this paper presents a research on recycling the bamboo fibers from bamboo residue for improving the performance of the asphalt mixtur... In order to comprehensively utilize the remaining bamboo residue of bamboo products,this paper presents a research on recycling the bamboo fibers from bamboo residue for improving the performance of the asphalt mixtures.First of all,the basic performance parameters of sinocalamus affinis fiber,phyllostachys pubescens fiber,green bamboo fiber were tested and analyzed,and the optimal content and length were put forward.Then,the mix ratio design of the bamboo fiber modified asphalt mixture was further designed through the response surface method,and was verified the rationality of the mix ratio.Finally,the mixture specimens were made according to the experimental design mix ratio,and the high temperature,low temperature performance and moisture susceptibility of the bamboo fiber modified mixtures asphalt were tested.The results showed that the high temperature performance,low temperature performance and moisture susceptibility of bamboo fiber modified asphalt mixtures were improved compared with the performance of SBS modified asphalt mixture.When the length of bamboo fiber is 7.25 mm and the content of 0.22%,the road performance of the asphalt mixture was optimal.Consequentially,the decomposition of bamboo residue into bamboo fiber and its application in asphalt pavement can improve the reuse of bamboo waste,with remarkable environmental benefits and great promotion value. 展开更多
关键词 bamboo fiber response surface method asphalt mixture proportion design road performances bamboo waste
原文传递
An Uncertainty Analysis and Reliability-Based Multidisciplinary Design Optimization Method Using Fourth-Moment Saddlepoint Approximation
13
作者 Yongqiang Guo Zhiyuan Lv 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第3期1855-1870,共16页
In uncertainty analysis and reliability-based multidisciplinary design and optimization(RBMDO)of engineering structures,the saddlepoint approximation(SA)method can be utilized to enhance the accuracy and efficiency of... In uncertainty analysis and reliability-based multidisciplinary design and optimization(RBMDO)of engineering structures,the saddlepoint approximation(SA)method can be utilized to enhance the accuracy and efficiency of reliability evaluation.However,the random variables involved in SA should be easy to handle.Additionally,the corresponding saddlepoint equation should not be complicated.Both of them limit the application of SA for engineering problems.The moment method can construct an approximate cumulative distribution function of the performance function based on the first few statistical moments.However,the traditional moment matching method is not very accurate generally.In order to take advantage of the SA method and the moment matching method to enhance the efficiency of design and optimization,a fourth-moment saddlepoint approximation(FMSA)method is introduced into RBMDO.In FMSA,the approximate cumulative generating functions are constructed based on the first four moments of the limit state function.The probability density function and cumulative distribution function are estimated based on this approximate cumulative generating function.Furthermore,the FMSA method is introduced and combined into RBMDO within the framework of sequence optimization and reliability assessment,which is based on the performance measure approach strategy.Two engineering examples are introduced to verify the effectiveness of proposed method. 展开更多
关键词 Reliability-based multidisciplinary design optimization moment method saddlepoint approximate sequence optimization and reliability assessment performance measure approach
下载PDF
Optimum Design of Stair-Climbing Robots Using Taguchi Method
14
作者 A.Arunkumar S.Ramabalan D.Elayaraja 《Intelligent Automation & Soft Computing》 SCIE 2023年第1期1229-1244,共16页
Environmental issues like pollution are major threats to human health.Many systems are developed to reduce pollution.In this paper,an optimal mobile robot design to reduce pollution in Green supply chain management sy... Environmental issues like pollution are major threats to human health.Many systems are developed to reduce pollution.In this paper,an optimal mobile robot design to reduce pollution in Green supply chain management system.Green supply chain management involves as similating environmentally and eco-nomically feasible solutions into the supply chain life-cycle.Smartness,advanced technologies,and advanced networks are becoming pillars of a sustainable supply chain management system.At the same time,there is much change happening in the logistics industry.They are moving towards a new logistics model.In the new model,robotic logistics has a vital role.The reasons for this change are the rapid growth of the e-commerce business and the shortage of workers.The advantages of using robotic logistics are reduction in human errors,faster delivery speed,better customer satisfaction,more safety for workers,and high workforce adaptability.A robot with rocker-bogie suspension is a six-wheeled mobile platform that has a distinctive potential to keep all wheels on the ground continuously.It has been designed to traverse rough and uneven terrain by distributing the load over its wheels equally.However,there is a limitation to achieving high-speed mobility against vertical barriers.In this research,an optimal design of product delivery wheeled robots for a sustainable supply chain system is proposed to ensure higher adaptability and maximum stability during climbing staircases.The design parameters of the proposed robot are optimized using Taguchi Method.The aim is to get a smooth trajectory of the robot’s center-of-mass.The proposed approach realizes a robot with much-improved stability which can climb over heights more than the size of the wheel(i.e.,3 times the radius of wheels).The results reveal that the modified rocker-bogie system not only increases the stair-climbing capability but also thwarts instability due to overturning of a wheel of the robot. 展开更多
关键词 Green supply chain management robotic logistics stair-climbing wheeled mobile robot optimum design rocker-bogie mechanism taguchi method
下载PDF
Design of N-11-Azaartemisinins Potentially Active against Plasmodium falciparum by Combined Molecular Electrostatic Potential, Ligand-Receptor Interaction and Models Built with Supervised Machine Learning Methods
15
作者 Jeferson Stiver Oliveira de Castro José Ciríaco Pinheiro +5 位作者 Sílvia Simone dos Santos de Morais Heriberto Rodrigues Bitencourt Antonio Florêncio de Figueiredo Marcos Antonio Barros dos Santos Fábio dos Santos Gil Ana Cecília Barbosa Pinheiro 《Journal of Biophysical Chemistry》 CAS 2023年第1期1-29,共29页
N-11-azaartemisinins potentially active against Plasmodium falciparum are designed by combining molecular electrostatic potential (MEP), ligand-receptor interaction, and models built with supervised machine learning m... N-11-azaartemisinins potentially active against Plasmodium falciparum are designed by combining molecular electrostatic potential (MEP), ligand-receptor interaction, and models built with supervised machine learning methods (PCA, HCA, KNN, SIMCA, and SDA). The optimization of molecular structures was performed using the B3LYP/6-31G* approach. MEP maps and ligand-receptor interactions were used to investigate key structural features required for biological activities and likely interactions between N-11-azaartemisinins and heme, respectively. The supervised machine learning methods allowed the separation of the investigated compounds into two classes: cha and cla, with the properties ε<sub>LUMO+1</sub> (one level above lowest unoccupied molecular orbital energy), d(C<sub>6</sub>-C<sub>5</sub>) (distance between C<sub>6</sub> and C<sub>5</sub> atoms in ligands), and TSA (total surface area) responsible for the classification. The insights extracted from the investigation developed and the chemical intuition enabled the design of sixteen new N-11-azaartemisinins (prediction set), moreover, models built with supervised machine learning methods were applied to this prediction set. The result of this application showed twelve new promising N-11-azaartemisinins for synthesis and biological evaluation. 展开更多
关键词 Antimalarial design MEP Ligand-Receptor Interaction Supervised Machine Learning methods Models Built with Supervised Machine Learning methods
下载PDF
Current situation and development trend of design methods for subgrade structure of high speed railways
16
作者 Yangsheng Ye Degou Cai +3 位作者 Qianli Zhang Shaowei Wei Hongye Yan Lin Geng 《Railway Sciences》 2023年第3期289-309,共21页
Purpose–This method will become a new development trend in subgrade structure design for high speed railways.Design/methodology/approach–This paper summarizes the structural types and design methods of subgrade bed ... Purpose–This method will become a new development trend in subgrade structure design for high speed railways.Design/methodology/approach–This paper summarizes the structural types and design methods of subgrade bed for high speed railways in China,Japan,France,Germany,the United States and other countries based on the study and analysis of existing literature and combined with the research results and practices of high speed railway subgrade engineering at home and abroad.Findings–It is found that in foreign countries,the layered reinforced structure is generally adopted for the subgrade bed of high speed railways,and the unified double-layer or multi-layer structure is adopted for the surface layer of subgrade bed,while the simple structure is adopted in China;in foreign countries,different inspection parameters are adopted to evaluate the compaction state of fillers according to their respective understanding and practice,while in China,compaction coefficient,subsoil coefficient and dynamic deformation modulus are adopted for such evaluation;in foreign countries,the subgrade top deformation control method,the subgrade bottom deformation control method,the subsurface fill strength control method are mainly adopted in subgrade bed structure design of high speed railways,while in China,dynamic deformation control of subgrade surface and dynamic strain control of subgrade bed bottom layer is adopted in the design.However,the cumulative deformation of subgrade caused by train cyclic vibration load is not considered in the existing design methods.Originality/value–This paper introduces a new subgrade structure design method based on whole-process dynamics analysis that meets subgrade functional requirements and is established on the basis of the existing research at home and abroad on prediction methods for cumulative deformation of subgrade soil. 展开更多
关键词 High speed railway Subgrade engineering Subgrade bed structure design method Existing research Development trend
下载PDF
The Ultimate Anti-Seismic Design Method
17
作者 Ioannis N. Lymperis 《Open Journal of Civil Engineering》 2023年第4期771-801,共31页
The design mechanisms and methods of the invention are intended to minimize problems related to the safety of structures in the event of natural phenomena such as earthquakes, tornadoes, and strong winds. It is achiev... The design mechanisms and methods of the invention are intended to minimize problems related to the safety of structures in the event of natural phenomena such as earthquakes, tornadoes, and strong winds. It is achieved by controlling the deformations of the structure. Damage and deformation are closely related concepts since the control of deformations also controls the damage. The design method of applying artificial compression to the ends of all longitudinal reinforced concrete walls and, at the same time, connecting the ends of the walls to the ground using ground anchors placed at the depths of the boreholes, transfers the inertial stresses of the structure in the ground, which reacts as an external force in the structure’s response to seismic displacements. The wall with the artificial compression acquires dynamic, larger active cross-section and high axial and torsional stiffness, preventing all failures caused by inelastic deformation. By connecting the ends of all walls to the ground, we control the eigenfrequency of the structure and the ground during each seismic loading cycle, preventing inelastic displacements. At the same time, we ensure the strong bearing capacity of the foundation soil and the structure. By designing the walls correctly and placing them in proper locations, we prevent the torsional flexural buckling that occurs in asymmetrical floor plans, and metal and tall structures. Compression of the wall sections at the ends and their anchoring to the ground mitigates the transfer of deformations to the connection nodes, strengthens the wall section in terms of base shear force and shear stress of the sections, and increases the strength of the cross-sections to the tensile at the ends of the walls by introducing counteractive forces. The use of tendons within the ducts prevents longitudinal shear in the overlay concrete, while anchoring the walls to the foundation not only dissipates inertial forces to the ground but also prevents rotation of the walls, thus maintaining the structural integrity of the beams. The prestressing at the bilateral ends of the walls restores the structure to its original position even inelastic displacements by closing the opening of the developing cracks. 展开更多
关键词 ULTIMATE Control-System ANTI-SEISMIC EARTHQUAKES CONSTRUCTION method design
下载PDF
Harmonic balance simulation of the influence of component uniformity and reliability on the performance of a Josephson traveling wave parametric amplifier
18
作者 郑煜臻 熊康林 +1 位作者 冯加贵 杨辉 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第4期339-343,共5页
A Josephson traveling wave parametric amplifier(JTWPA),which is a quantum-limited amplifier with high gain and large bandwidth,is the core device of large-scale measurement and control systems for quantum computing.A ... A Josephson traveling wave parametric amplifier(JTWPA),which is a quantum-limited amplifier with high gain and large bandwidth,is the core device of large-scale measurement and control systems for quantum computing.A typical JTWPA consists of thousands of Josephson junctions connected in series to form a transmission line and hundreds of shunt LC resonators periodically loaded along the line for phase matching.Because the variation of these capacitors and inductors can be detrimental to their high-frequency characteristics,the fabrication of a JTWPA typically necessitates precise processing equipment.To guide the fabrication process and further improve the design for manufacturability,it is necessary to understand how each electronic component affects the amplifier.In this paper,we use the harmonic balance method to conduct a comprehensive study on the impact of nonuniformity and fabrication yield of the electronic components on the performance of a JTWPA.The results provide insightful and scientific guidance for device design and fabrication processes. 展开更多
关键词 Josephson traveling wave parametric amplifier(JTWPA) harmonic balance method YIELDS uniformITY
原文传递
An Efficient Reliability-Based Optimization Method Utilizing High-Dimensional Model Representation and Weight-Point Estimation Method
19
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
下载PDF
Underdetermined direction of arrival estimation with nonuniform linear motion sampling based on a small unmanned aerial vehicle platform
20
作者 Xinwei Wang Xiaopeng Yan +2 位作者 Tai An Qile Chen Dingkun Huang 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第3期352-363,共12页
Uniform linear array(ULA)radars are widely used in the collision-avoidance radar systems of small unmanned aerial vehicles(UAVs).In practice,a ULA's multi-target direction of arrival(DOA)estimation performance suf... Uniform linear array(ULA)radars are widely used in the collision-avoidance radar systems of small unmanned aerial vehicles(UAVs).In practice,a ULA's multi-target direction of arrival(DOA)estimation performance suffers from significant performance degradation owing to the limited number of physical elements.To improve the underdetermined DOA estimation performance of a ULA radar mounted on a small UAV platform,we propose a nonuniform linear motion sampling underdetermined DOA estimation method.Using the motion of the UAV platform,the echo signal is sampled at different positions.Then,according to the concept of difference co-array,a virtual ULA with multiple array elements and a large aperture is synthesized to increase the degrees of freedom(DOFs).Through position analysis of the original and motion arrays,we propose a nonuniform linear motion sampling method based on ULA for determining the optimal DOFs.Under the condition of no increase in the aperture of the physical array,the proposed method obtains a high DOF with fewer sampling runs and greatly improves the underdetermined DOA estimation performance of ULA.The results of numerical simulations conducted herein verify the superior performance of the proposed method. 展开更多
关键词 Unmanned aerial vehicle(UAV) uniform linear array(ULA) Direction of arrival(DOA) Difference co-array Nonuniform linear motion sampling method
下载PDF
上一页 1 2 250 下一页 到第
使用帮助 返回顶部