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巧用PB的定义条件属性按钮
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作者 李玉玲 《福建电脑》 2006年第6期204-204,共1页
讨论了PowerBuilder数据窗口中的定义条件属性按钮的巧妙应用。通过两个例子说明其应用方法和技巧。
关键词 POWERBUILDER 数据窗口 定义条件属性按钮 数据库
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CAD曲面等值分割方法 被引量:2
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作者 胡靖尘 郑国磊 《计算机辅助设计与图形学学报》 EI CSCD 北大核心 2021年第1期153-160,共8页
CAD曲面分割在工程领域中具有广泛的应用.已有分割方法主要根据单一的面点属性进行分割,不具通用性.为此,提出以自定义条件为核心的面等值分割方法.用户预先根据分割问题及相关面点属性设计一组条件,以此为依据计算界点,并沿界边生长方... CAD曲面分割在工程领域中具有广泛的应用.已有分割方法主要根据单一的面点属性进行分割,不具通用性.为此,提出以自定义条件为核心的面等值分割方法.用户预先根据分割问题及相关面点属性设计一组条件,以此为依据计算界点,并沿界边生长方向依次搜索界点,进而以有序界点样条插值的方式生成界边.通过构造曲面及其子面片的界边,将曲面分割为一组等值面.为保证分割的一般性,提出初始界点和参数域采样单元界点精确计算方法.最后,针对可加工性、法向量和曲率3种面点属性分别设计分割条件并进行实例测试,在可加工区域分割测试中文中方法的平均界点误差比现有方法平均降低96.98%.实验结果表明,所提方法适用于不同的分割问题,且具有较高的分割精度. 展开更多
关键词 面等值分割 定义条件 界点 二分查找
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Poisson Theory of Generalized Birkhoff Systems 被引量:2
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作者 梁景辉 李元成 梅凤翔 《Journal of Beijing Institute of Technology》 EI CAS 2000年第1期5-10,共6页
To study the Poisson theory of the generalized Birkhoff systems, the Lie algebra and the Poisson brackets were used to establish the Poisson theorem. The generalized Poisson condition for the first integral and the ge... To study the Poisson theory of the generalized Birkhoff systems, the Lie algebra and the Poisson brackets were used to establish the Poisson theorem. The generalized Poisson condition for the first integral and the generalized Poisson theorem of the generalized Birkhoff systems are obtained. An example is given to illustrate the application of the result. 展开更多
关键词 analytical mechanics generalized Birkhoff system generalized Poisson condition generalized Poisson theorem
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论说谎者悖论和罗素悖论的辩证矛盾本质 被引量:3
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作者 刘高岑 《河南师范大学学报(哲学社会科学版)》 CSSCI 1998年第2期31-34,共4页
论说谎者悖论和罗素悖论的辩证矛盾本质刘高岑人们公认悖论可以分为两类:语义悖论和逻辑—数学悖论。最典型最深刻的语义悖论是说谎者悖论;而罗素悖论则被认为是逻辑—数学悖论的典型代表。关于这两个悖论,国内主要有三种观点。一种... 论说谎者悖论和罗素悖论的辩证矛盾本质刘高岑人们公认悖论可以分为两类:语义悖论和逻辑—数学悖论。最典型最深刻的语义悖论是说谎者悖论;而罗素悖论则被认为是逻辑—数学悖论的典型代表。关于这两个悖论,国内主要有三种观点。一种观点认为这两个悖论都是“混淆了部分... 展开更多
关键词 说谎者悖论 罗素悖论 知识系统 辩证矛盾 数学悖论 逻辑矛盾 集合的元素 可拓集 康托集 定义条件
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高校人事管理信息系统研制试探 被引量:1
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作者 吴圣龙 顾志香 龚允陈 《扬州大学学报(高教研究版)》 1997年第4期19-20,共2页
关键词 高校人事管理 管理信息系统(MIS) 系统研制 数据库 基本情况 查询与统计 骨干教师 定义条件 字典库 查询统计
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The Necessary and Sufficient Conditions for Two Kinds of Matrix Equtions Having Semipositive Subdefinite Solutions 被引量:1
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作者 何楚宁 《Chinese Quarterly Journal of Mathematics》 CSCD 2002年第4期62-68,共7页
Finding solutions of matrix equations in given set SR n×n is an active research field. Lots of investigation have done for these cases, where S are the sets of general or symmetric matrices and symmetric posit... Finding solutions of matrix equations in given set SR n×n is an active research field. Lots of investigation have done for these cases, where S are the sets of general or symmetric matrices and symmetric positive definite or sysmmetric semiposite definite matrices respectively . Recently, however, attentions are been paying to the situation for S to be the set of general(semi) positive definite matrices(called as semipositive subdefinite matrices below) . In this paper the necessary and sufficient conditions for the following two kinds of matrix equations having semipositive, subdefinite solutions are obtained. General solutions and symmetric solutions of the equations (Ⅰ) and (Ⅱ) have been considered in in detail. 展开更多
关键词 semipositive subdefinite symmetric semipositie definite generalized singualr value decomposition
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浅谈离域π键 被引量:1
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作者 杨先明 《商情》 2007年第3期71-71,共1页
在全国高中学生化学竞赛中经常会遇到如此类型的问题:画出NO3-的结构,NO3-中有离域π键吗?N、O原子之间的键级是多少?要解决此类问题,就必须弄清楚离域π键。由于离域π键较抽象,高中生在学习时感到困难较大,现就如何快速准确理解、掌... 在全国高中学生化学竞赛中经常会遇到如此类型的问题:画出NO3-的结构,NO3-中有离域π键吗?N、O原子之间的键级是多少?要解决此类问题,就必须弄清楚离域π键。由于离域π键较抽象,高中生在学习时感到困难较大,现就如何快速准确理解、掌握和应用离域π键谈谈个人的看法。 展开更多
关键词 定义条件 杂化 π键电子数 键级 应用
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Consistent Criteria for checking Hypotheses
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作者 Laura Eliauri Malkhaz Mumladze Zurab Zerakidze 《Journal of Mathematics and System Science》 2013年第10期514-518,共5页
This paper we study a consistent criterion for checking Hypotheses. Given definition of consistent criterion for checking hypotheses for family probability measures which were defined by Z. Zerakidze (see 5). We pro... This paper we study a consistent criterion for checking Hypotheses. Given definition of consistent criterion for checking hypotheses for family probability measures which were defined by Z. Zerakidze (see 5). We prove the necessary and sufficient conditions are obtained for the existence of consistent criteria of hypotheses. For example we clearly build of a consistent criteria for checking hypotheses. 展开更多
关键词 Consistent criterion ORTHOGONAL SEPARABLE hypotheses.
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Identification of Health and Welfare Parameters for Rabbit Production and Definition of an Evaluation Score
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作者 M. Cerioli R. Brivio +2 位作者 C. Tittarelli G. Grilli A. Lavazza 《Journal of Agricultural Science and Technology(A)》 2011年第4X期500-507,共8页
The knowledge on rabbit welfare may be improved by the use of correct tools for monitoring the different aspects of rabbit industrial farming. Therefore, the aim of this study was to define parameters related to healt... The knowledge on rabbit welfare may be improved by the use of correct tools for monitoring the different aspects of rabbit industrial farming. Therefore, the aim of this study was to define parameters related to health and welfare of animals in industrial farms with intensive husbandry. Health, management, environmental and productive parameters were firstly characterized and then a protocol to assess welfare of rabbits was define. The research was conducted on 8 industrial farms from 2004 to 2007 and around 30 inspections were done in each farm. At each visit, the health conditions were established by: (1) necropsy on animals of different productive category; (2) specific laboratory investigations based on the lesions observed; (3) checking the presence of parasites in environmental faecal samples; (4) bacteriological examination of vaginal, nasal and rectal swabs of rabbit of different age. The immune conditions and the efficacy of vaccinations were measured by determining anti-Myxomatosis and anti-Rabbit Haemorrhagic Disease antibodies using competitive ELISAs, and anti-Encephalitozoon cunicoli antibodies by immunocarbonassay. The environmental conditions were evaluated by measuring air temperature, relative humidity, ammonia concentration and bacterial/fungal count. Finally the productive parameters were also recorded and elaborated. All the entered values were then utilized for defining a score system to establish health and welfare conditions. 展开更多
关键词 RABBIT welfare monitoring health and zootechnical parameters environmental conditions score system.
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Definition of Stationarity Based on Monitoring the Uncertainty at Real Measurement Conditions
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作者 Alois Heiss Woelfel Engineering Group 《Journal of Mechanics Engineering and Automation》 2018年第2期71-81,共11页
In the statistical standard literature the stationarity of a time dependent process generally is defined by the invariance in time of the distribution of the variable, like a SPL (sound pressure level) fluctuating i... In the statistical standard literature the stationarity of a time dependent process generally is defined by the invariance in time of the distribution of the variable, like a SPL (sound pressure level) fluctuating in time. However in reality there cannot exist constant distribution, respectively characteristics, in time in the strict mathematical sense because the time intervals of observation only can be finite due to practical reasons. Hence on every distribution and characteristics based on it a certain, but evaluable uncertainty is imposed. For monitoring these uncertainties the online-measurement technique, i.e. primarily appropriate software, is already available, also for customers. According to this state of the art the following expanded definition of the stationarity is proposed: Stationarity during a quality controlled measurement process becomes established, when the upper confidence limit of the interesting specific characteristic has no positive slope in time and correspondingly the lower confidence limit of the specific characteristic no negative slope and, as a third, a common condition, the interesting specific characteristic has adjusted itself to a constant position in time. From this a systematic criteria scheme is established and in examples applied on different in- and outdoor situations of sound impact. 展开更多
关键词 Stochastic processes stationarity UNCERTAINTY criteria.
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Global Asymptotically Stable of a Generalized Discrete Ricker Competition System
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作者 Yoshihiro Hamaya 《Journal of Mathematics and System Science》 2013年第6期282-288,共7页
The purpose of this article is to investigate the sufficient conditions for the global asymptotic stability of one equilibrium point of a generalized Ricker competition system,……which appears as a model for dynamics... The purpose of this article is to investigate the sufficient conditions for the global asymptotic stability of one equilibrium point of a generalized Ricker competition system,……which appears as a model for dynamics with one extinct species, by applying the technique of average functions and the new principle of competitive exclusion. 展开更多
关键词 Generalized discrete ricker competition systems average functions new principle of competitive exclusion.
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高职酒店管理专业“订单培养”模式研究
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作者 田园 周丽芝 杨华 《林区教学》 2014年第4期15-17,共3页
高等职业教育的培养目标是以就业为导向,以企业需求为目标,以专业技能为培养核心。订单培养是以提高毕业生就业质量为本,以加快推进职业教育培养模式向工学结合、校企合作转变为中心,以双向服务为宗旨,该人才培养模式是校企合作的... 高等职业教育的培养目标是以就业为导向,以企业需求为目标,以专业技能为培养核心。订单培养是以提高毕业生就业质量为本,以加快推进职业教育培养模式向工学结合、校企合作转变为中心,以双向服务为宗旨,该人才培养模式是校企合作的有效载体,为学校走产学研相结合发展之路提供了有效的平台。 展开更多
关键词 定义条件 存在问题 操作实例
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解函数题常见错误剖析
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作者 刘延炳 陈德前 《中学生数理化(初中版)(初三)》 2003年第11期13-16,共4页
函数是初中数学的重要内容,不少同学由于对函数概念和性质理解不透,在解题时常出现错误,现就常见错误予以剖析. 一、忽视函数定义中的条件例1 已知二次函数y=kx2-7x-7的图象和x轴有交点,则k的取值范围是( ).
关键词 函数 解题错误 初中 数学教学 代数 自变量 取值范围 定义条件 隐含条件 函数图象
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A CENTRAL LIMIT THEOREM FOR STRONG NEAR-EPOCH DEPENDENT RANDOM VARIABLES 被引量:2
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作者 LINZHENGYAN QIUJIN 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 2004年第2期263-274,共12页
In this paper, a central limit theorem for strong near-epoch dependent sequences of random variables introduced in [9] is showed. Under the same moments condition,the authors essentially weaken the "size" re... In this paper, a central limit theorem for strong near-epoch dependent sequences of random variables introduced in [9] is showed. Under the same moments condition,the authors essentially weaken the "size" requirement mentioned in other papers about near epoch dependence. 展开更多
关键词 Mixingale MIXING Near-epoch dependent Strong near-epoch dependent Central limit theorem
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Contrastive Analysis of Cooling Performance between a High-level Water Col-lecting Cooling Tower and a Typical Cooling Tower 被引量:10
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作者 WANG Miao WANG Jin +1 位作者 WANG Jiajin SHI Cheng 《Journal of Thermal Science》 SCIE EI CAS CSCD 2018年第1期39-47,共9页
A three-dimensional (3D) numerical model is established and validated for cooling performance optimization between a high-level water collecting natural draft wet cooling tower (HNDWCT) and a usual natural draft w... A three-dimensional (3D) numerical model is established and validated for cooling performance optimization between a high-level water collecting natural draft wet cooling tower (HNDWCT) and a usual natural draft wet cooling tower (UNDWCT) under the actual operation condition at Wanzhou power plant, Chongqing, China. User defined functions (UDFs) of source terms are composed and loaded into the spray, fill and rain zones. Consider- ing the conditions of impact on three kinds of corrugated fills (Double-oblique wave, Two-way wave and S wave) and four kinds of fill height (1.25 m, 1.5 m, 1.75 m and 2 In), numerical simulation of cooling performance are analysed. The results demonstrate that the S wave has the highest cooling efficiency in three fills for both towers, indicating that fill characteristics arc crucial to cooling performance. Moreover, the cooling performance of the HNDWCT is far superior to that of the UNDWCT with fill height increases of 1.75 m and above, because the air mass flow rate in the fill zone of the HNDWCT improves more than that in the UNDWCT, as a result of the rain zone resistance declining sharply for the HNDWCT. In addition, the mass and heat transfer capacity of the HNDWCT is better in the tower centre zone than in the outer zone near the tower wall under a uniform fill layout. This behaviour is inverted for the UNDWCT, perhaps because the high-level collection devices play the role of flow guiding in the inner zone. Therefore, when non-uniform fill layout optimization is applied to the HNDWCT, the inner zone increases in height from 1.75 m to 2 m, the outer zone reduces in height from 1.75 m to 1.5 m, and the outlet water temperature declines approximately 0.4 K compared to that of the uniform layout. 展开更多
关键词 HNDWCT UNDWCT 3D Numerical Model Non-uniform FiB Layout Cooling Performance
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The Riemann Problem with Delta Data for Zero-Pressure Gas Dynamics 被引量:1
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作者 Li WANG 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 2016年第3期441-450,共10页
In this paper, the Riemann problem with delta initial data for the onedimensional system of conservation laws of mass, momentum and energy in zero-pressure gas dynamics is considered. Under the generalized Rankine-Hug... In this paper, the Riemann problem with delta initial data for the onedimensional system of conservation laws of mass, momentum and energy in zero-pressure gas dynamics is considered. Under the generalized Rankine-Hugoniot conditions and the entropy condition, we constructively obtained the global existence of generalized solutions which contains delta-shock. Moreover, the author obtains the stability of generalized solutions by making use of the perturbation of the initial data. 展开更多
关键词 Zero-pressure gas dynamics Generalized Rankine-Hugoniot conditions Delta-shock
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Second order duality for multiobjective programming with cone constraints 被引量:1
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作者 TANG Li Ping YAN Hong YANG Xin Min 《Science China Mathematics》 SCIE CSCD 2016年第7期1285-1306,共22页
We focus on second order duality for a class of multiobjective programming problem subject to cone constraints. Four types of second order duality models are formulated. Weak and strong duality theorems are establishe... We focus on second order duality for a class of multiobjective programming problem subject to cone constraints. Four types of second order duality models are formulated. Weak and strong duality theorems are established in terms of the generalized convexity, respectively. Converse duality theorems, essential parts of duality theory, are presented under appropriate assumptions. Moreover, some deficiencies in the work of Ahmad and Agarwal(2010) are discussed. 展开更多
关键词 multiobjective programming cone constraints second order duality
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