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1.
针对云制造环境下资源语义描述和服务匹配问题,在充分考虑用户个性化需求与制造资源异构性的基础上,分析了云制造资源描述和服务匹配的难点,利用规范化描述的特点,将制造资源描述问题转化为Web语义描述问题,提出一种通用的制造资源语义描述框架。结合4种相似度算法,设计了阀值和权重,提出了基于过滤器的服务匹配策略。实验结果证明了该策略和算法的有效性和可行性。应用这4种相似度算法能够有效缩小匹配的规模,提高了服务的查找效率与准确度。  相似文献   

2.
云制造环境下设计需求与服务匹配模式算法   总被引:1,自引:0,他引:1  
针对云制造环境下设计需求与设计服务的特性,构建含有属性集、关系集和操作集的设计需求与设计服务数据结构。建立一种云制造环境下的设计需求与设计服务输入、分解、组合和输出匹配模式,研究了该模型的原子匹配、扩展匹配和产品匹配。针对匹配过程中输入、分解、组合和输出量化问题,采用语义概念相似度和循环递归设计结构匹配算法实现设计需求与设计服务智能匹配。最后,通过实验验证,表明该模式与算法的有效性和可行性。  相似文献   

3.
交流平台     
<正>BME型固定式高剪切乳化机启东市长江机电有限公司生产的BME型固定式高剪切乳化机采用常压设计,不含机械密封;安装于常压的反应釜,处理量为30 L~20 000 L,能满足不同的生产需要,可配合反应釜使用,也可定制加长;工作温度≤180℃;处理量为10 L/批~20 000L/批;安装位置有偏心、垂直、倾斜等多种安装形式。  相似文献   

4.
1958—2012年郑州市极端气温和极端气温事件年际变化特征   总被引:5,自引:4,他引:1  
为了探究郑州市极端气温和极端气温事件的变化特征及其未来发展趋势,根据1958—2012年郑州市逐日最高、最低气温资料,以百分位阀值法确定了逐年的极端气温阀值,并统计出极端高温和低温天气日数,运用Mann-Kendall非参数秩次相关检验法和小波分析法研究了郑州市过去55年年最低气温、年最高气温、极端高温阀值、极端低温阀值、极端高温天气日数和极端低温天气日数的年际变化特征、突变特征和周期变换特征,并运用了R/S分析进行了预测。结果表明:(1)郑州市年最高气温、极端高温阀值和高温天气日数都呈现减少趋势,而年最低气温、极端低温阀值和低温天气日数都呈增加趋势;(2)郑州市年最高气温、最低气温和年极端低温阀值及极端低温发生日数都发生了明显的突变,并在突变后达到显著水平,而极端低温阀值及极端低温发生日数并未发生明显的突变;(3)周期变化特征上,4种气象要素都存在明显的变化周期,且都是大周期嵌套在小周期的变化特征;(4)从突变特征和周期变化来看,在未来几年,极端高温天气日数将持续增加,极端低温天气日数将持续减少;(5)R/S指数研究表明,最高气温会从减少趋势转化为增加趋势,年最低气温和极端高温天气日数会从增加趋势转化为减少趋势,极端低温天气日数仍会呈现增加趋势。  相似文献   

5.
为了了解当代大学生对奶茶的消费程度、类型、方式等习惯,给消费者及相关产业提出合情合理的消费方式和发展建议,采取市场调研、问卷调查、数据分析等手段进行调查研究。通过调查发现,大学生更加青睐于饮品店所销售的产品,奶茶产品的社交和娱乐属性将会逐渐取代奶茶产品原来的饮料属性,奶茶产品会向个性化、定制化、高端化发展。  相似文献   

6.
<正>立足数据分析市场服务企业精准营销主要业务及服务内容:立足大数据,分析全球农药产业现状及趋势,跟踪全球农药产品流通走向,分析热点产品供求双方购买关系,精确锁定目标市场,结合知识营销模式,为客户量身定制产业投资、项目建设、产品销售解决方案;实时监控行情变化、价格异动、产品更新、科技创新,为企业经营决策提供咨询服务。  相似文献   

7.
农村中小企业不同成长阶段战略管理研究   总被引:1,自引:1,他引:0  
崔太康 《中国农学通报》2011,27(23):184-188
分析了农村中小企业发展过程中战略管理方面存在的问题和由于缺乏应有的战略管理而面临的成长风险。在此基础上,针对农村中小企业的内部条件和外部环境的复杂性与不确定性,综合国内相关研究成果,总结提出了农村中小企业实施战略管理的要点:(1)农村中小企业战略管理要具有灵活性,战略实施时间一般较短,要不断进行战略转型。并依据行业生命周期理论,提出了企业处在不同的成长阶段,匹配以不同的战略措施;(2)战略管理幅度的有限性,大多数农村中小企业产品比较单一,战略管理的幅度一般局限于单个或者几个市场的运作上。农村中小企业战略管理的特性是其自身条件和所处环境决定的。  相似文献   

8.
介绍了"食品工艺学"课程的培养内容、目标和现状,提出了将现代信息技术与思维导图结合的教学改革思路,详述了"思维导图+互联网+互动反馈系统"教学法在"食品工艺学"课程中的实施方法,包括教学设计、课前预习、课堂教学、课后作业和复习与反馈5个阶段,对教学效果和实施要求进行了总结,为食品专业相关课程的教学探索提供参考。  相似文献   

9.
产品本身之外的异杂物,是影响产品品质的一个重要原因,也是占客户反馈和客户索赔百分比最高的因素之一。阐述异杂物类别、危害及来源,为了有效控制产品中的异杂物,针对不同异杂物类别、来源进行分析并有针对性地提出相应预防措施,以便在产品生产过程中使异杂物得到有效控制,提高产品的品质,控制产品的生产成本。  相似文献   

10.
从产业化角度讨论了发展大麦小麦若叶产品的现实意义。通过对收集的19个国内外品牌大麦若叶产品营养成分含量进行最大值、最小值、均值、变异系数等统计分析,评价不同品牌大麦若叶产品的质量稳定性,并分析产生差异的主要原因,讨论小麦苗生产若叶苗粉的可行性。在此基础上,提出提高大麦小麦若叶产品质量与效益的对策建议。  相似文献   

11.
虚拟关节臂式坐标测量机模型的构建与验证   总被引:1,自引:0,他引:1  
关节臂式坐标测量机的测量误差受到众多因素的影响,且由物理构件带来的误差无法被消除。为此,笔者旨在构建一种虚拟关节臂式坐标测量机。首先,采用D-H矩阵建立其运动学模型,其次,利用PC-DMIS测量软件分析测量机数据并对模型的精确性进行检验,最后使用蒙特卡罗法和测量机模型完成仿真测量。通过与实际参数构建的模型、制造商参数构建的模型相对比,可知所构建测量机模型的测量精度能够满足要求。仿真结果表明提出的模型构建与验证方法对坐标测量的应用具有较高的工程价值。  相似文献   

12.
A product ontology screening method which can be used in variant design is proposed. With the support of complete ontology view of product resources, the product functional requirement and structural characteristics are converted to demand constraints, which are used to screen product ontology. For different screening hierarchies and objects, different screening rules such as pattern matching, case matching combined with manual decision and auto matching on the basis of case-based reasoning are adopted. The semi-automatic screening method with human-computer cooperation has impressive effectiveness on the improvements of the accuracy of design schemes and the flexibility and efficiency of design process. Finally, a variant design supporting system for building door and window is developed, which proves the feasibility and effectiveness of the method.  相似文献   

13.
Belt grinding machine with multi axis computer number control(CNC) system can effectively process parts with complex moulding surfaces.In this paper,iso parametric and iso planar tool path planning strategies customized for this kind of machine are proposed.The tool path generation methods are designed based on the analysis of the belt grinding process.By using least square method,optimized cross section normal is computed in the iso planar method.To improve the design efficiency of path planning,reduce experiments and increase economical benefit,the geometric simulation program based on linear grinding model is developed.Experiment on a turbine blade profile shows that the proposed algorithms work satisfyingly.  相似文献   

14.
By analyzing shortages of current MSPCA model, an on line multi variable statistical process monitoring method is proposed, which uses some concepts from online multi scale filtering and can be applied to sensor fault diagnosis. In the method, wavelet decomposition is employed to the signals using edge correction filter in a fixed length data window, and then wavelet denoising is conducted with wavelet threshold filtering. Next, an on line multi scale model is constructed for data combining wavelet transformation and adaptive PCA in the previous data window. This model avoids time waste in direct signal denoising and reduces time cost in multi scale data with conventional PCA, which eventually increases accuracy in fault diagnosis. Experiments on eight vibration signals of 6135D diesel engine under severe leak condition prove the practicability and feasibility of the proposed method.  相似文献   

15.
The vibration is a great obstacle of motorcycle enterprise development. To solve this problem, matching performance technology of the motorcycle is presented in the researches on the general design of the motorcycle. Based on finite element method and vibration theory, matching performance of the motorcycle has been studied, and the international general software MSC. PATRAN/NASTRAN has been used to analyze the best match between the engine and the frame of a type of motorcycle. An effective method has been formed, which can solve the problem of the vibration of the motorcycle essentially, and shorten the development period of motorcycle, reduce the development cost. It has very important theoretical meaning and great value in engineering application for motorcycle enterprise to design products.  相似文献   

16.
A novel method simulating a brushless direct current(DC) motor was presented, based on principles of hybrid system modeling and finite state machine theory. Brushless DC motor control mainly focuses on controlling the on/off condition and power switch duration. Modes of control therefore can be defined by corresponding states, and the states can be combined as a finite state machine. This approach uses the popular Simulink/Stateflow simulation method to control brushless DC motor loops. A three phase brushless DC motor was analyzed to illustrate the process of model building with Simulink/Stateflow. The analysis demonstrates the feasibility and validity of the proposed method.  相似文献   

17.
In view of the complexity of the measuring environment and uncertainty of the a prior knowledge for rocket aviation,a rocket safety control system based on uncertainty reasoning is proposed.The uncertain representation and processing of the knowledge in expert systems are established according to the characteristics of the parameters .Following the characteristics of the decision rules and decision procudure,the reasoning control strategy is studied and the method for conflict resolving strategy and searching strategy is proposed.Then,the uncertain matching rules and the feasibility degree delivering method are expressed,and the decision-making network and the rule-based uncertainty reseaoning model were constructed.Simulation experiments show that this system can acquire the craft launching information quickly and accurately,which greatly improves the reliability and authenticity of safety control decision for rocket aviation,and can control the rocket aviating state effectively.  相似文献   

18.
Based on the analysis of the water pollution spatial distribution characters of Yangtze River in Chongqing,a new method based on the integration of BP neural network and genetic arithmetic(GA) is proposed.For some shortcomings existed in the standard BP neural network,this method has ultimately overcome these shortcomings by combining the GA with BP artificial neural network through altering stimulating function,adding momentum factor to power value for BP algorithm and introducing genetic arithmetic to searching for the knots of the hidden layer,momentum factor and learning level.Using this method can easily overcome the difficulty of measuring the water prediction model's parameters.GIS is used as a tool for data management and spatial analysis,and the prediction result of the model for the water pollution spatial distribution characters of Yangtze River in Chongqing is visualized and explored with the precision of more than 78%.  相似文献   

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