检索结果-南通市图书馆

Simulation and Experimental Research on Liquid Spreading in a Wire-Sawn Kerf

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Journal of Mechanical Engineering 2023年第6期36卷 247-260页

作者： Lin Lin hui Huang State Key Institute of Manufacturing Engineering Huaqiao UniversityXiamen 361021China

The significance of liquids in abrasive wire sawing has been demonstrated in several ***,the perfor-mance of its spreading behavior is limited by the current development trend,where the wafer has a larger area and the kerf is ***,there are very few studies on the liquid spreading behavior in wire-sawn ***,a 3D CFD(computational fluid dynamics)model is presented in this paper and used to simulate the liquid spreading behavior in a kerf based on a VOF(volume of fluid)method with a CSF(continuum surface force)model,which is used to simulate multiphase flow,and an empirical correlation for characterizing the liquid dynamic contact angle using UDF(user defined functions).Subsequently,parametric simulations are performed on the kerf area,kerf width,liquid viscosity,liquid surface tension,and liquid velocity at the inlet area of the kerf,and verification experi-ments are conducted to determine the validity of the simulation *** the simulation and experimental results,three typical liquid spreading regimes that exhibit different effects on wire sawing in the kerfs are found,and their limiting conditions are identified using non-dimensional ***,a prediction model is pro-posed for the liquid spreading regime based on a set of Weber and Capillary *** wire sawing,an increase in the wafer area does not change the liquid spreading regime in the kerf;however,a reduction in the kerf width sig-nificantly hinders the liquid spreading ***,the spreading regime can be effectively converted to facili-tate wire sawing by adjusting the physical properties and supply conditions of the liquid.

关键词： Spreading regime Kerf CFD Non-dimensional analysis Prediction model

Avoiding Non-Manhattan Obstacles Based on Projection of Spatial Corners in Indoor Environment

在线全文

学校读者我要写书评

暂无评论

IEEE/CAA Journal of Automatica Sinica 2020年第4期7卷 1190-1200页

作者： Luping Wang hui Wei the School of Mechanical Engineering University of Shanghai for Science and TechnologyShanghai 200093China the Laboratory of Algorithms for Cognitive Models Shanghai Key Laboratory of Data ScienceSchool of Computer ScienceFudan UniversityShanghai 201203China

Monocular vision-based navigation is a considerable ability for a home mobile robot. However, due to diverse disturbances, helping robots avoid obstacles, especially nonManhattan obstacles, remains a big challenge. In indoor environments, there are many spatial right-corners that are projected into two dimensional projections with special geometric configurations. These projections, which consist of three lines,might enable us to estimate their position and orientation in 3 D scenes. In this paper, we present a method for home robots to avoid non-Manhattan obstacles in indoor environments from a monocular camera. The approach first detects non-Manhattan obstacles. Through analyzing geometric features and constraints,it is possible to estimate posture differences between orientation of the robot and non-Manhattan obstacles. Finally according to the convergence of posture differences, the robot can adjust its orientation to keep pace with the pose of detected non-Manhattan obstacles, making it possible avoid these obstacles by itself. Based on geometric inferences, the proposed approach requires no prior training or any knowledge of the camera’s internal parameters,making it practical for robots navigation. Furthermore, the method is robust to errors in calibration and image noise. We compared the errors from corners of estimated non-Manhattan obstacles against the ground truth. Furthermore, we evaluate the validity of convergence of differences between the robot orientation and the posture of non-Manhattan obstacles. The experimental results showed that our method is capable of avoiding non-Manhattan obstacles, meeting the requirements for indoor robot navigation.

关键词： Avoiding obstacle monocular vision navigation non-Manhattan obstacle spatial corner

Robust Regression Analysis for Clustered Interval-Censored Failure Time Data

在线全文

学校读者我要写书评

暂无评论

Journal of Systems Science & Complexity 2021年第3期34卷 1156-1174页

作者： LUO Lin ZHAO hui School of Mathematics and Statistics Central China Normal UniversityWuhan 430079China School of Statistics and Mathematics Zhongnan Univer'sity of Economics and LawWuhan 430064China

Clustered interval-censored failure time data often occur in a wide variety of research and application fields such as cancer and AIDS studies. For such data, the failure times of interest are interval-censored and may be correlated for subjects coming from the same cluster. This paper presents a robust semiparametric transformation mixed effect models to analyze such data and use a U-statistic based on rank correlation to estimate the unknown parameters. The large sample properties of the estimator are also established. In addition, the authors illustrate the performance of the proposed estimate with extensive simulations and two real data examples.

关键词： Clustered data interval-censoring random effects rank estimation semiparametric transformation models

Nondeterministic Fuzzy Simulation and Bisimulation

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Electronics 2020年第2期29卷 297-303页

作者： DENG hui LI Zhi School of Electro-Mechanical Engineering Xidian University

As the abstraction and equivalent technologies, simulation and bisimulation have been applied to the simplifications of some classical and uncertain models structures. The studies of the more generalized simulation and bisimulation technologies have not proceeded *** this problem in mind, we introduce the concepts,lemmas, theorems of nondeterministic fuzzy simulation and bisimulation, as well as the relevant proofs. According to the definitions of nondeterministic fuzzy simulation and bisimulation, we propose nondeterministic fuzzy quotients and a series of quotienting algorithms to generate the minimization of nondeterministic fuzzy simulation and bisimulation. By comparison with previous quotienting algorithms, we show that our quotienting algorithms are more generalized. This kind of quotienting algorithms not only suit for Nondeterministic fuzzy Kripke structure(NFKS), but also Fuzzy Kripke structure(FKS)and classical Kripke structure.

关键词： Nondeterministic fuzzy kripke structure(NFKS) Nondeterministic fuzzy simulation Nondeterministic fuzzy bisimulation Nondeterministic fuzzy quotient

Light People:Professor Manijeh Razeghi

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Light(Science & Applications) 2024年第8期13卷 1451-1462页

作者： hui Wang Cun Yu Changchun Institute of Optics Fine Mechanics and PhysicsChinese Academy of SciencesChangchun 130033China

The sense of light is the first sensation the human body *** importance of light is ***,we all know that the light we can see and perceive covers only a small section of the ***,for Light People,we feature a researcher who is committed to exploring different spectral bands of light ranging from deep ultraviolet to terahertz waves and working on quantum semiconductor technology,*** Razeghi of the Northwestern University in the United *** for her quick thinking and witty remarks,*** is passionate about life and always kind to *** a scientist,she does not limit her research to a single focus,instead,she works on the entire process from material selection,device design,processing,and manufacturing,all the way to product *** has a strong passion for education,a commitment unwavered by fame or *** her students,she is both a reliable source of knowledge and a motherly figure with a caring *** firmly believes that all things in nature can give her energy and *** science,she is a true“pioneer”in research and a“miner”of scientific *** advises young scientists to enjoy and love what they do,and turn their research into their *** a female scientist,she calls on all women to realize their true value and ***,let’s hear from Professor Manijeh Razeghi,a true star who radiates energy and light.

关键词： mother instead passion

A Novel Green Supplier Selection Method Based on the Interval Type-2 Fuzzy Prioritized Choquet Bonferroni Means

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

IEEE/CAA Journal of Automatica Sinica 2021年第9期8卷 1549-1566页

作者： Peide Liu hui Gao School of Management Science and Engineering Shandong University of Finance and EconomicsJinan 250014China School of Business Heze UniversityHeze 274015China

In view of the environment competencies,selecting the optimal green supplier is one of the crucial issues for enterprises,and multi-criteria decision-making(MCDM)methodologies can more easily solve this green supplier selection(GSS)*** addition,prioritized aggregation(PA)operator can focus on the prioritization relationship over the criteria,Choquet integral(CI)operator can fully take account of the importance of criteria and the interactions among them,and Bonferroni mean(BM)operator can capture the interrelationships of ***,most existing researches cannot simultaneously consider the interactions,interrelationships and prioritizations over the criteria,which are involved in the GSS ***,the interval type-2 fuzzy set(IT2FS)is a more effective tool to represent the ***,based on the advantages of PA,CI,BM and IT2FS,in this paper,the interval type-2 fuzzy prioritized Choquet normalized weighted BM operators with fuzzy measure and generalized prioritized measure are proposed,and some properties are ***,a novel MCDM approach for GSS based upon the presented operators is developed,and detailed decision steps are ***,the applicability and practicability of the proposed methodology are demonstrated by its application in the shared-bike GSS and by comparisons with other *** advantages of the proposed method are that it can consider interactions,interrelationships and prioritizations over the criteria simultaneously.

关键词： Bonferroni mean operator Choquet integral operator Green supplier selection(GSS) interval type-2 fuzzy set(IT2FS) prioritized aggregation operator

ANALYSIS ON AGRICULTRUAL INFORMATION DEMAND——Case of Jilin Province

在线全文

学校读者我要写书评

暂无评论

Chinese Geographical Science 2005年第3期15卷 281-287页

作者： ZHANG hui-min JIANG hui-ming Northeast Institute of Geography and Agricultural Ecology Chinese Academy of Sciences Changchun 130012 P. R. China Managerial College Jilin Agricultural University Changchun 130118 P. R. China

With the rapid development of agricultural informalization in the world, the demand of agricultural information has been a focus in the international agriculture and information fields. Based on the investigation, this paper presented the four characteristics of the demand of agricultural information in China, includingregionality, seasonality, great potential demand and variation in kind and level. The factors infuencing the demand of agricultural information were analyzed by the Optimized Less Square （OLS） method. The result shows that, of all factors influcing agricultural information demand, the most important one is economy, the second is facility of information pass, and knowledge and education of user, credit of agricultural information service system and production situation follow. Taking Jilin Province as an example, this article also elaborated the agricultural information demand status, and deduced the regression model of agricultural information demand and verified it by the survey in rural Jilin.

关键词： agricultural information demand agricultural information service system Jilin Province

Geological division of gas in the Pingdingshan mine area based on its tectonic dynamics characteristics

在线全文

学校读者我要写书评

暂无评论

International Journal of Mining Science and Technology 2015年第5期25卷 827-833页

作者： Lei Dongji Li hui Meng hui State Key Laboratory Cultivation Base for Gas Geology and Gas Control Henan Polytechnic University Collaborative Innovation Center of Central Plains Economic Region for Coalbed/Shale Gas State Key Laboratory of Coal Resources and Safe Mining China University of Mining & Technology

In this paper,we used tectonic dynamics theories to study the tectonic evolution characteristics of the Pingdingshan mine area,and analyzed the impact of tectonic progressive control on gas *** study results are as follows:the Pingdingshan mine area has been mainly controlled by multiple squeezing and shearing actions of the Qinling orogenic belt since early and middle Yanshan,forming the tectonic control characteristics of master control in two directions,namely NWW trending and NNE trending;the NWW trending structure is dominated by squeezing and shearing,while the NNE trending structure is dominated by *** controlled by the structure,the gas occurrence presents partition and zonation,*** with the western structure,the eastern NWW-NW trending structure of the mine area is more highly developed,resulting in the mine area gas occurrence distribution characteristics are distinct in the east while indistinct in the *** on this,the mine area can be divided into the following two geological dynamic areas:the western half of mine area,namely the Guodishan fault control area,where the NW-SE trending synchronous tension action suffered by the northeast side(footwall) is relatively strong,and compared with the southwest side(hanging wall),its coal and gas outburst seriousness is weak;and the eastern half of mine area,namely the NWW-NW thrust nappe fracture fold control area,which is a serious area of coal and gas outburst,in particular the axial area of the Likou syncline is the intersection compound and combination position of the NW and NE trending structures,a tectonic concentrated area,and the gas pressure and content here are the largest.

关键词： Tectonic evolution Tectonic environment Dynamic division Tectonic division

The Adjacency Graphs of a Class of LFSRs and Their Applications

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Electronics 2019年第6期28卷 1210-1216页

作者： WANG hui FENG Xiutao Academy of Mathematics and Systems Science Chinese Academy of Sciences Science and Technology on Communication Security Laboratory

Nonlinear feedback shift registers（NFSRs）are widely used in communication and cryptography. How to construct more NFSRs with maximal periods, which can generate sequences with maximal periods, i.e., de Brujin sequences, is an attractive problem. Recently many results on constructing de Bruijn sequences from adjacency graphs of Linear feedback shift registers（LFSRs） by means of the cycle joining method have been obtained. In this paper we discuss a class of LFSRs with characteristic polynomial p;（x）, where p（x） is a primitive polynomial of degree n ≥ 2 over the finite field F;. As results, we determine their cycle structures and adjacency graphs, and further construct a class of new de Bruijn sequences from these LFSRs.

关键词： Nonlinear feedback shift register(NFSR) de Bruijn sequence Cycle structure Adjacency graph