期刊文献+
共找到51,957篇文章
< 1 2 250 >
每页显示 20 50 100
Design of Fully Automatic Specification Selection System for Resistance Welding Equipment
1
作者 Xiangkun Lu Zengtai Tian +1 位作者 Hao Xu Yue Guo 《Journal of Harbin Institute of Technology(New Series)》 CAS 2024年第1期64-68,共5页
A system for fully automatic selection of welding specifications in resistance welding equipment has been developed to address the problem of workers frequently choosing the wrong specifications during manual welding ... A system for fully automatic selection of welding specifications in resistance welding equipment has been developed to address the problem of workers frequently choosing the wrong specifications during manual welding of multiple parts on a single machine in automobile factories. The system incorporates an automatic recognition system for different workpiece materials using the added machine fixture,visual detection system for nuts and bolts,and secondary graphical confirmation to ensure the correctness of specification calling. This system achieves reliable,fully automatic selection of welding specifications in resistance welding equipment and has shown significant effects in improving welding quality for massproduced workpieces,while solving the problem of specification calling errors that can occur with traditional methods involving process charts and code adjustments. This system is particularly suitable for promoting applications in manual welding of multiple parts on a single machine in automobile factories,ensuring correct specification calling and welding quality. 展开更多
关键词 seat spot welding welding specifications fully automatic
下载PDF
Product Specification Analysis for Modular Product Design Using Big Sales Data
2
作者 Jian Zhang Bingbing Li +1 位作者 Qingjin Peng Peihua Gu 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2023年第1期19-33,共15页
Big data on product sales are an emerging resource for supporting modular product design to meet diversified customers’requirements of product specification combinations.To better facilitate decision-making of modula... Big data on product sales are an emerging resource for supporting modular product design to meet diversified customers’requirements of product specification combinations.To better facilitate decision-making of modular product design,correlations among specifications and components originated from customers’conscious and subconscious preferences can be investigated by using big data on product sales.This study proposes a framework and the associated methods for supporting modular product design decisions based on correlation analysis of product specifications and components using big sales data.The correlations of the product specifications are determined by analyzing the collected product sales data.By building the relations between the product components and specifications,a matrix for measuring the correlation among product components is formed for component clustering.Six rules for supporting the decision making of modular product design are proposed based on the frequency analysis of the specification values per component cluster.A case study of electric vehicles illustrates the application of the proposed method. 展开更多
关键词 Modular product design Customer preference Product specifications Correlation analysis Big sales data Electric vehicle
下载PDF
渐近平均伪轨跟踪性质、弱specification性质和分布混沌 被引量:2
3
作者 王立冬 王翔 刘恒 《大连民族大学学报》 2016年第1期43-46,共4页
证明了有渐近平均伪轨跟踪性质的非平凡紧致动力系统具有一致分布混沌或者按序列分布混沌。此外,在具有渐近平均伪轨跟踪性质系统中的分布混沌在测度中心是一致和稠密的,即有一个不可数的一致分布混沌集是由这样的点组成,它们的轨道闭... 证明了有渐近平均伪轨跟踪性质的非平凡紧致动力系统具有一致分布混沌或者按序列分布混沌。此外,在具有渐近平均伪轨跟踪性质系统中的分布混沌在测度中心是一致和稠密的,即有一个不可数的一致分布混沌集是由这样的点组成,它们的轨道闭包包含测度中心。作为一个推论,具有弱specification性质的系统也有类似的结果。 展开更多
关键词 渐近平均伪轨跟踪 specification性质 分布混沌 按序列分布混沌
下载PDF
关于弱Specification性质的一个注记 被引量:3
4
作者 吴新星 《数学物理学报(A辑)》 CSCD 北大核心 2017年第4期601-606,共6页
该文证明具有弱specification性质的系统在其测度中心的限制系统也具有弱specification性质,并且其逆不真.作为推论得到在未有满射的假设下,弱specification性质蕴含渐近平均跟踪性质.最后证明具有弱specification性质的满射系统是一致... 该文证明具有弱specification性质的系统在其测度中心的限制系统也具有弱specification性质,并且其逆不真.作为推论得到在未有满射的假设下,弱specification性质蕴含渐近平均跟踪性质.最后证明具有弱specification性质的满射系统是一致分布混沌的. 展开更多
关键词 测度中心 specification 渐近平均跟踪性质 分布混沌
下载PDF
弱Specification和逆极限空间上移位映射(英文) 被引量:2
5
作者 顾荣宝 《安徽大学学报(自然科学版)》 CAS 1998年第3期18-22,共5页
对度量空间上连续自映射引进弱Specification概念,研究了它与浑沌和拓扑熵的联系,此外还讨论了逆极限空间上移位映射的弱Specification性质。
关键词 specification 逆极限空间 移位映射 度量空间
下载PDF
连续映射的弱specification性质与混沌
6
作者 乔宗敏 朱夜明 顾荣宝 《合肥工业大学学报(自然科学版)》 CAS CSCD 2004年第9期1066-1069,共4页
specification性质是一种重要的动力性质,对连续的区间映射和树映射,该性质与拓扑混合等价。对紧致度量空间,满足POTP性质的拓扑混合映射具有specification性质。文章对紧致度量空间上连续自映射,研究了弱specification性质与各种混沌... specification性质是一种重要的动力性质,对连续的区间映射和树映射,该性质与拓扑混合等价。对紧致度量空间,满足POTP性质的拓扑混合映射具有specification性质。文章对紧致度量空间上连续自映射,研究了弱specification性质与各种混沌之间的关系,证明了具有弱specification性质的系统是Li-Yorke意义下混沌的,是Ruelle-Takens意义下混沌的,是处处混沌的,并且具有性质P。 展开更多
关键词 连续自映射 specification 混沌
下载PDF
弱Specification性质与不变概率测度
7
作者 乔宗敏 顾荣宝 《安徽大学学报(自然科学版)》 CAS 2004年第5期8-10,共3页
对紧致度量空间上连续自映射,研究了弱Specification性质与不变概率测度之间的关系,证明了具有弱Specification性质的系统一定存在f:X→X的不变概率测度m,使得Suppm=X,并且f:X→X有满测度中心,即M(f)=X.
关键词 specification性质 不变概率测度 连续自映射 紧致度量空间
下载PDF
弱Specification和伪移位不变集(英文)
8
作者 顾荣宝 《安徽大学学报(自然科学版)》 CAS 2002年第3期1-4,共4页
研究了弱Specification性质与紧致度量空间上连续映射的伪移位不变集的联系 ,得到的主要结果是 :设f∶X→X是紧致度量空间连续自映射 ,若f具有弱Specification性质 ,则存在正整数M ,使得fM具有伪移位不变集。
关键词 紧致度量空间 连续映射 specification 伪移位不变集 连续自映射
下载PDF
一些紧致系统的拓扑序列熵和广义specification性质 被引量:2
9
作者 胡超杰 马东魁 《广东工业大学学报》 CAS 2007年第2期24-26,共3页
研究了紧致度量空间上的连续满射f:X→X和逆极限空间上移位映射σf:Xf→Xf的拓扑序列熵的性质和逆极限空间上移位映射的广义spec ification性质.
关键词 移位映射 逆极限空间 拓扑序列熵 广义specification
下载PDF
具有specification性质的连续流
10
作者 张刚 卢占会 朱玉峻 《华北电力大学学报(自然科学版)》 CAS 北大核心 2003年第6期100-103,共4页
研究了具有specification性质连续流的动力性质。主要结论是:(1)具有specmcation性质的连续流是混沌的,且其拓扑熵大于零;(2)specmcation性质在扭扩及逆极限下是不变的。
关键词 混沌 specification性质 连续流 逆极限
下载PDF
基于UML Specification实现软件系统测试自动化
11
作者 高晨红 陈英 刘旸 《测试技术学报》 2004年第z2期141-144,共4页
本文基于软件系统测试理论及面向对象技术,结合一个合理的可以应用于实践的系统软件自动测试工具模型BUS-SUITE,分析基于UML Spec.实现软件系统测试自动化的理论基础、实现流程及关键技术.
关键词 系统测试 测试自动化 软件规格说明书(specification) UML模型
下载PDF
Improvement of the Assay Method for Steviol Glycosides in the JECFA Specifications 被引量:2
12
作者 Atsuko Tada Kyoko Ishizuki +6 位作者 Junichi Iwamura Hirohisa Mikami Yoshiko Hirao Isao Fujita Takeshi Yamazaki Hiroshi Akiyama Yoko Kawamura 《American Journal of Analytical Chemistry》 2013年第4期190-196,共7页
Steviol glycosides are natural sweetener constituents found in the leaves of Stevia rebaudiana Bertoni (Asteraceae). The specifications for steviol glycosides were established by the Joint FAO/WHO Expert Committee on ... Steviol glycosides are natural sweetener constituents found in the leaves of Stevia rebaudiana Bertoni (Asteraceae). The specifications for steviol glycosides were established by the Joint FAO/WHO Expert Committee on Food Additives (JECFA) in 2008, although there was a call in the following year for the modification of this assay method to enable the determination of nine steviol glycosides rather than just seven. In response, based on a proposed method by the Japan Stevia Association, we developed an improved method by changing the HPLC conditions and including the use of an octadecylsilyl column instead of an amino-bonded column to enable the rapid and reliable determination of the nine steviol glycosides by an isocratic HPLC-UV method. With the developed method, the nine steviol glycosides can be separately determined, and identified using individual reference chemicals as standards, unlike the previous identification method, which was based on the relative retention times. In addition, the single stevioside quantification standard was replaced with both stevioside and rebaudioside A quantification standards. Importantly, the validation of the developed method was successful. The limits of quantification for the nine steviol glycosides were between 0.2% and 0.6%. The developed assay method for the nine steviol glycosides was proposed to JECFA and adopted as the revised assay method for the steviol glycosides specifications at its 73rd meeting in 2010. 展开更多
关键词 STEVIOL GLYCOSIDES STEVIOSIDE Rebaudioside A REVERSED-PHASE HPLC JECFA specificationS
下载PDF
PXI Express specification tutorial 被引量:2
13
作者 National Instruments 《国外电子测量技术》 2007年第5期1-5,共5页
IntroductionThe PXI industry standard has quickly gained adoption and grown in prevalence in automated test systems since its release in 1998. PXI is being selected as the platform of choice for thousands of applicati... IntroductionThe PXI industry standard has quickly gained adoption and grown in prevalence in automated test systems since its release in 1998. PXI is being selected as the platform of choice for thousands of applications, from areas such as military and aerospace, consumer electronics, and communications, to process control and industrial automation. One of the key elements driving the rapid adoption of PXI is its use of PCI in the communication backplane. Now, as the commercial PC industry drastically improves the available bus bandwidth by evolving PCI to PCI Express, PXI has the ability to meet even more application needs by integrating PCI Express into the PXI standard. 展开更多
关键词 PXI Express specification tutorial PCI HIGH
下载PDF
具有specification性质的连续流的不变测度
14
作者 张刚 《石家庄师范专科学校学报》 2001年第4期1-4,共4页
具有强 specification性质的连续流 。
关键词 连续流 specification性质 不变测度 Borel概率测度 周期转轨 动力系统
下载PDF
Building tissue niches for stem cell lineage specification
15
作者 Weiwei Wang Sha Jin Kaiming Ye 《医用生物力学》 EI CAS CSCD 北大核心 2013年第S1期84-85,共2页
Introduction The success in lineage-specific differentiation of human embryonic and induced pluripotent stem(hES/iPS)cells raises new hopes for cell-based therapies.It is envisioned that cells differentiated from hES/... Introduction The success in lineage-specific differentiation of human embryonic and induced pluripotent stem(hES/iPS)cells raises new hopes for cell-based therapies.It is envisioned that cells differentiated from hES/iPS cells can be used to replace or repair damaged or diseased cells and tissues in body.This has not yet been possible due to the difficulty in generating biologically functional cells in vitro.While many factors may contribute to these failures,the lack of tissue niches in the current differentiation systems has been viewed in impairing the maturation of these cells.As revealed by studying mice embryo development,organ development requires strict temporal and spatial control at each stage.The stepwise hESC differentiation 展开更多
关键词 embryonic PLURIPOTENT diseased biologically specification DIFFERENTIATED LINEAGE maturation STEPWISE DIFFICULTY
原文传递
The Quality Specifications of Mischmetal Wire and Rod and the Method of Adding Rare Earth in Steel
16
作者 鞠远峰 左生华 +3 位作者 林勤 刘爱生 王群 林东晖 《Journal of Rare Earths》 SCIE EI CAS CSCD 1994年第3期231-233,共3页
TheQualitySpecificationsofMischmetalWireandRodandtheMethodofAddingRareEarthinSteel¥JuYuan-Feng;ZuoSheng-Hua(... TheQualitySpecificationsofMischmetalWireandRodandtheMethodofAddingRareEarthinSteel¥JuYuan-Feng;ZuoSheng-Hua(HubeiCrystalineSi... 展开更多
关键词 mischmetal WIRE and ROD QUALITY specification Adding METHOD
下载PDF
A FORMAL SPECIFICATION LANGUAGE FOR DYNAMIC STRAND SPACE MODEL
17
作者 LIU Dong-xi(刘东喜) +3 位作者 LI Xiao-yong(李晓勇) BAI Ying-cai(白英彩) 《Journal of Shanghai Jiaotong university(Science)》 EI 2002年第1期23-25,35,共4页
Specification language is used to provide enough information for the model of the cryptographic protocol. This paper first extends strand space model to dynamic strand model, and then a formal specification language f... Specification language is used to provide enough information for the model of the cryptographic protocol. This paper first extends strand space model to dynamic strand model, and then a formal specification language for this model is defined by using BNF grammar. Compared with those in literatures, it is simpler because of only concerning the algebraic properties of cryptographic protocols. 展开更多
关键词 DYNAMIC STRAND SPACE CRYPTOGRAPHIC protocols FORMAL specification LANGUAGE
下载PDF
A FORMAL MODEL FOR ANALYZING THE SCR-STYLE REQUIREMENTS SPECIFICATIONS
18
作者 Xu Yu Wu Guoqing +1 位作者 Liu Xiang Chen Xinmeng 《Wuhan University Journal of Natural Sciences》 CAS 1998年第2期142-142,共1页
Based on SCR(Software Cost Reduction), this paper presents a formal mOdel analyzingSCR-style requirements- This model mainly apply state trans1ation rules, semantic computing rules and attributes to define formal seme... Based on SCR(Software Cost Reduction), this paper presents a formal mOdel analyzingSCR-style requirements- This model mainly apply state trans1ation rules, semantic computing rules and attributes to define formal sementics of a tabular notation in the SCR requirements method, and may automatically analyze requirements specifications to be specified by the SCR method. Combining with a simp1eexample, this paper introduces how to analyze consistency and completeness of requirements specifica-tlons. 展开更多
关键词 state TRANSITION RULES SEMANTIC COMPUTING RULES attributes requirements specification
下载PDF
“SPECIFICATION PLUS TRANSFORMATION TO PROGRAM”:A NEW MODEL OF SOFTWARE DEVELOPMENT
19
作者 沈军 程正潮 《Journal of Southeast University(English Edition)》 EI CAS 1995年第2期63-70,共8页
In this paper, a formal specification language and a tool systembased on it are presented. With the tool system, the new model of softwaredevelopment─“specification plus transformation to program” can be im-pleme... In this paper, a formal specification language and a tool systembased on it are presented. With the tool system, the new model of softwaredevelopment─“specification plus transformation to program” can be im-plemented. 展开更多
关键词 SOFTWARE specification SOFTWARE engineering MODULE softwaredevelopment MODEL
下载PDF
Refinement and Transformation from Z Specification to C+ +
20
作者 Zhang Xiaoying(张晓莺) +1 位作者 Chen Jiaxun(陈家训) 《Journal of Donghua University(English Edition)》 EI CAS 2001年第4期97-102,共6页
As a kind of formal specification language, Z has gained a position in the field of software development, but there is still no standard way of transforming Z specification into executable code that is promising in in... As a kind of formal specification language, Z has gained a position in the field of software development, but there is still no standard way of transforming Z specification into executable code that is promising in increasing the quality, reusability and maintainability of software.With the automatic programming model of software engineering, through the analysis for Z specification language, a feasible semi-automatic way of refinement and transformation is proposed, and the correctness of the procedure is also discussed. 展开更多
关键词 Z specification refiinement transformation C + + Class template FUNCTION TEMPLATE
下载PDF
上一页 1 2 250 下一页 到第
使用帮助 返回顶部