检索结果-南通市图书馆

Job shop scheduling problem based on DNA computing

在线全文

学校读者我要写书评

暂无评论

Journal of Systems Engineering and Electronics 2006年第3期17卷 654-659页

作者： Yin Zhixiang Cui jianzhong yang Yan Ma Ying Dept. of Mathematics and Physics Anhui Univ. of Science and Technology Huainan 232001 P.R. China

To solve job shop scheduling problem, a new approach-DNA computing is used in solving job shop scheduling problem. The approach using DNA computing to solve job shop scheduling is divided into three stands. Finally, optimum solutions are obtained by sequencing A small job shop scheduling problem is solved in DNA computing, and the ＂operations＂ of the computation were performed with standard protocols, as ligation, synthesis, electrophoresis etc. This work represents further evidence for the ability of DNA computing to solve NP-complete search problems.

关键词： DNA computing job shop scheduling problem weighted tournament.

Anisotropic Force Ellipsoid Based Multi-axis Motion Optimization of Machine Tools

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Mechanical Engineering 2012年第5期25卷 960-967页

作者： PENG Fangyu YAN Rong CHEN Wei yang jianzhong LI Bin State Key Laboratory of Digital Manufacturing Equipment and Technology Huazhong University of Science and Technology Wuhan 430074 China National NC System Engineering Research Center Huazhong University of Science and Technology Wuhan 430074 China

The existing research of the motion optimization of multi-axis machine tools is mainly based on geometric and kinematic constraints, which aim at obtaining minimum-time trajectories and finding obstacle-free paths. In motion optimization, the stiffness characteristics of the whole machining system, including machine tool and cutter, are not considered. The paper presents a new method to establish a general stiffness model of multi-axis machining system. An analytical stiffness model is established by Jacobi and point transformation matrix method. Based on the stiffness model, feed-direction stiffness index is calculated by the intersection of force ellipsoid and the cutting feed direction at the cutter tip. The stiffness index can help analyze the stiffness performance of the whole machining system in the available workspace. Based on the analysis of the stiffness performance, multi-axis motion optimization along tool paths is accomplished by mixed programming using Matlab and Visual C＋＋. The effectiveness of the motion optimization method is verified by the experimental research about the machining performance of a 7-axis 5-linkage machine tool. The proposed research showed that machining stability and production efficiency can be improved by multi-axis motion optimization based on the anisotropic force ellipsoid of the whole machining system.

关键词： stiffness force ellipsoid multi-axis motion optimization

INVERSE CENTER LOCATION PROBLEM ON A TREE

在线全文

学校读者我要写书评

暂无评论

Journal of Systems Science & Complexity 2008年第4期21卷 651-664页

作者： Xiaoguang yang jianzhong ZHANG Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing 100190 China. United International College Hong Kong Baptist University Zhuhai 519085 China.

This paper discusses the inverse center location problem restricted on a tree with different costs and bound constraints. The authors first show that the problem can be formulated as a series of combinatorial linear programs, then an O（｜V｜^2 log ｜V｜） time algorithm to solve the problem is presented. For the equal cost case, the authors further give an O（｜V｜） time algorithm.

关键词： Center location combinatorial linear program tree two-terminal series parallel graphs.

Task-Oriented Topology System Synthesis of Reconfigurable Legged Mobile Lander Integrating Active and Passive Metamorphoses

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Mechanical Engineering 2023年第3期36卷 89-109页

作者： Youcheng Han Ziyue Li Gaohan Zhu Weizhong Guo jianzhong yang Wei Liu State Key Lab of Mechanical System and Vibration School of Mechanical EngineeringShanghai Jiao Tong UniversityShanghai 200240China Beijing Institute of Spacecraft System Engineering Beijing 100094China

To explore hostile extraterrestrial landforms and construct an engineering prototype,this paper presents the task-oriented topology system synthesis of reconfigurable legged mobile lander(ReLML)with three operation modes from adjusting,landing,to *** with our preceding works,the adjusting mode with three rotations(3R)provides a totally novel exploration approach to geometrically matching and securely arriving at complex terrains dangerous to visit currently;the landing mode is redefined by two rotations one translation(2R1T),identical with the tried-and-tested Apollo and Chang'E landers to enhance survivability via reasonable touchdown buffering motion;roving mode also utilizes 2R1T motion for good motion and force *** reconfigurable mechanism theory is first brought into synthesizing legged mobile lander integrating active and passive metamorphoses,composed of two types of metamorphic joints and metamorphic execution and transmission *** reveal metamorphic principles with multiple finite motions,the finite screw theory is developed to present the procedure from unified mathematical representation,modes and source phase derivations,metamorphic joint and limb design,to final structure *** identify the prototype topology,the 3D optimal selection matrix method is proposed considering three operation modes,five evaluation criteria,and two topological ***,simulation verifies the whole task implementation process to ensure the reasonability of design.

关键词： Legged mobile lander Topology synthesis Active and passive metamorphoses Finite screw Metamorphic joint Reconfigurable mechanism

脓毒症相关凝血功能障碍机制和生物标志物及治疗研究新进展

在线全文

学校读者我要写书评

暂无评论

中国医药 2025年第1期20卷 157-160页

作者：娜孜拉·海热提何勇波杨建中新疆医科大学第一附属医院急诊科乌鲁木齐830011

脓毒症是一种由感染触发的全身炎症反应综合征,也是导致危重症患者死亡的主要因素之一。脓毒症引发的凝血功能障碍不仅是威胁生命的一种并发症,也是脓毒症患者病情恶化的关键因素。因此,深入研究脓毒症凝血功能障碍的机制和相关的生物... 详细信息

脓毒症是一种由感染触发的全身炎症反应综合征,也是导致危重症患者死亡的主要因素之一。脓毒症引发的凝血功能障碍不仅是威胁生命的一种并发症,也是脓毒症患者病情恶化的关键因素。因此,深入研究脓毒症凝血功能障碍的机制和相关的生物标志物,将有助于临床医师更早地识别这些问题,从而改善患者的预后情况,并为临床医师提供新的治疗方向。

关键词：脓毒症凝血功能障碍机制生物标志物治疗

在线全文

学校读者我要写书评

暂无评论

反射性隔热膜在PVC地板上的应用开发

广州化工 2025年第1期53卷 82-85,97页

作者：姚健叶鑫庞磊杨建中舒婷宜宾天亿新材料科技有限公司四川宜宾644000

主要阐述了采用在PVC地板板材表面贴合一层隔热层的实验思路,实现降低板材整体在高强度光照下整体温度的效果,以解决PVC地板无法在高强度光照环境下长时间使用的问题。相关实验已经证明,PVC地板拥有抗菌防霉,耐磨耐压,无甲醛环保等优势... 详细信息

主要阐述了采用在PVC地板板材表面贴合一层隔热层的实验思路,实现降低板材整体在高强度光照下整体温度的效果,以解决PVC地板无法在高强度光照环境下长时间使用的问题。相关实验已经证明,PVC地板拥有抗菌防霉,耐磨耐压,无甲醛环保等优势,以及安装便捷,使用年限长,脚感舒适,皮肤亲和性好等人为体感上的优势。但因其无法耐受长时间高强度光照,有较大的使用局限性,本次实验目的为延长地板在长时间日照条件下的老化时间和使用年限,并从降低光的漫反射以及减少光污染层面达到节能减排的功效,制备出环境友好,使用局限性小的新型PVC地板。

关键词： PVC 隔热层板材节能减排抗老化

Toward Intelligent Machine Tool

在线全文

学校读者我要写书评

暂无评论

Engineering 2019年第4期5卷 679-690页

作者： Jihong Chen Pengcheng Hu Huicheng Zhou jianzhong yang Jiejun Xie Yakun Jiang Zhiqiang Gao Chenglei Zhang National Numerical Control System Engineering Research Center Huazhong University of Science and TechnologyWuhan 430074China

With the development of modern information technology-and particularly of the new generation of artificial intelligence(AI)technology-new opportunities are available for the development of the intelligent machine tool(IMT).Based on the three classical paradigms of intelligent manufacturing as defined by the Chinese Academy of Engineering,the concept,characteristics,and systemic structure of the IMT are presented in this *** stages of machine tool evolution-from the manually operated machine tool(MOMT)to the IMT-are discussed,including the numerical control machine tool(NCMT),the smart machine tool(SMT),and the ***,the four intelligent control principles of the IMT-namely,autonomous sensing and connection,autonomous learning and modeling,autonomous optimization and decision-making,and autonomous control and execution-are presented in *** paper then points out that the essential characteristic of the IMT is to acquire and accumulate knowledge through learning,and presents original key enabling technologies,including the instruction-domain-based analytical approach,theoretical and big-data-based hybrid modeling technology,and the double-code control *** on this research,an intelligent numerical control(INC)system and industrial prototypes of IMTs are *** intelligent practices are conducted,demonstrating that the integration of the new generation of AI technology with advanced manufacturing technology is a feasible and convenient way to advance machine tools toward the IMT.

关键词： Intelligent manufacturing Intelligent machine tool Intelligent numerical controller New-generation artificial intelligence

CPS Modeling of CNC Machine Tool Work Processes Using an Instruction-Domain Based Approach

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

Engineering 2015年第2期1卷 247-260页

作者： Jihong Chen jianzhong yang Huicheng Zhou Hua Xiang Zhihong Zhu Yesong Li Chen-Han Lee Guangda Xu National Numerical Control System Engineering Research Center Huazhong University of Science and Technology

Building cyber-physical system(CPS) models of machine tools is a key technology for intelligent manufacturing. The massive electronic data from a computer numerical control(CNC) system during the work processes of a CNC machine tool is the main source of the big data on which a CPS model is established. In this work-process model, a method based on instruction domain is applied to analyze the electronic big data, and a quantitative description of the numerical control(NC) processes is built according to the G code of the processes. Utilizing the instruction domain, a work-process CPS model is established on the basis of the accurate, real-time mapping of the manufacturing tasks, resources, and status of the CNC machine tool. Using such models, case studies are conducted on intelligent-machining applications, such as the optimization of NC processing parameters and the health assurance of CNC machine tools.

关键词： cyber-physical system (CPS) big data computer numerical control (CNC) machine tool electronic data of work processes instruction domain intelligent machining

Measurement of T wave in magnetocardiography using tunnel magnetoresistance sensor

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 Physics B 2023年第2期32卷 5-10页

作者：陆知宏纪帅杨建中 Department of Precision Instrument Tsinghua UniversityBeijing 100084China Beijing Innovation Center for Future Chips Beijing 100084China State Key Laboratory of Precision Measurement Technology and Instruments Tsinghua UniversityBeijing 100084China

Several critical clinical applications of magnetocardiography(MCG)involve its T *** T wave’s accuracy directly affects the diagnostic accuracy of MCG for ischemic heart disease and *** magnetoresistance(TMR)attracts attention as a new MCG measurement ***,the T waves measured by TMR are often drowned in *** accuracy of T waves needs to be discussed to determine the clinical value of MCG measured by *** study uses an improved empirical mode decomposition(EMD)algorithm and averaging to eliminate the noise in the MCG measured by *** MCG signals measured by TMR are compared with MCG measured by the optically pumped magnetometer(OPM)to judge its *** the MCG measured by OPM as a reference,the relative errors in time and amplitude of the T wave measured by TMR are 3.4%and 1.8%,*** is the first demonstration that TMR can accurately measure the time and amplitude of MCG T *** ability to provide reliable T wave data illustrates the significant clinical application value of TMR in MCG measurement.

关键词： magnetocardiography tunnel magnetoresistance optically pumped magnetometer T wave detection