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1.
The sustainability of water resources is one of the major concerns of the world. Industries are finding ways to minimize water costs and to reduce water pollution through efficient use of supplies. One of effective solutions is the use of water pinch technology or process integration techniques. Property integration emerged as the third trend of process integration technique (aside from energy and mass integration) to solve the problem of water network synthesis by considering physical stream properties such as pH or resistivity. Various techniques have been done to solve this property-based problem. In this paper, mixed integer non-linear programming (MINLP) problems with topological constraints is studied. Nowadays, various evolutionary algorithms are also used to solve such MINLP problems. In this study, particle swarm optimization is used to solve the property integration problem. A comparison is made between this algorithm and commercial genetic algorithm (GA) applications. Particle swarm optimization is observed to perform favorably compared to GA.  相似文献   

2.
Manufacturing enterprise today has become a matter of effective and efficient application of information technology and knowledge-based engineering. Several new manufacturing paradigms such as virtual enterprise (or extended enterprise) and mass customization have resulted in a highly distributed and autonomous manufacturing system. On the one hand, this will increase the competitiveness of a firm in terms of quickly meeting dynamic changes in the market; on the other hand, this will also increase the difficulty of integrating different information and knowledge systems residing in each member firm. This integration is also called enterprise application integration (EAI) (here the term application means information systems or software systems for supporting manufacturing or service activities). The methodology for EAI has been studied for at least a decade; but no satisfactory solution has been found from a practical viewpoint. EAI is becoming even more difficult due to the boom in various enterprise information and knowledge systems (and also to ever increasing competition in the technical software market). The study presented in this paper conducted a critical analysis of existing solutions to EAI. We consider EAI as having two generic issues: semantic integration and syntactic integration. The main problem of semantic integration reduces to the general problem of enterprise or business modelling. The main problem of syntactic integration reduces to the general problem of software architecture of enterprise applications which enables interoperability between any two EAs. While the first issue is studied in the manufacturing field, the second issue is studied in the computing engineering field. In this paper, both issues are put together under the context of EAI and studied. The result of the study, together with our experience with one Canadian manufacturing firm, has led to the identification of several issues to be addressed in the future. We also outline possible ways to approach these issues.  相似文献   

3.
一种基于数据集成的EAI解决方案   总被引:8,自引:0,他引:8  
针对企业应用集成(EAI)中数据集成模式的两大局限,提出了一种新型的基于数据集成的EAI解决方案。文章首先给出了该数据集成方案的体系结构,然后对数据集成过程中的若干关键技术进行了研究,提出了功能型集成数据的概念,达到以数据集成实现功能集成的目的;提出了支持数据抽取映射数据集和支持数据传输的传输定义集概念,解决异构数据库的动态数据转换问题;就整个数据集成过程以事务处理的方式保证其完整性和一致性,并给出了程序流程图。最后给出了实际案例,验证了方案的可行性。  相似文献   

4.
Global supply chain practices and their effects have received considerable attention over the last two decades. In the recent past, the need for integration across supply chains has been identified as a key for effective and efficient operations of supply chains. This is observed with the increasing trend of collaborative partnerships among supply chain partners. This paper presents an integrated approach for manufacturing and distribution networks within the supply chain system of a global car company. The paper shows that the integration of manufacturing and distribution networks creates the environment for effective planning of many components and execution/follow-up of those plans. These components include materials, resources, operations/activities, suppliers and customers. The main features of the integration include component integration at individual networks via use of a central warehouse. This integration reduces various interfacing steps between partners and enables representations of relationships (component precedence, parent-component and component-component). The proposed integrated model is numerically tested using past data from one of Japan's auto-makers, based in the emerging economy of Thailand. The paper concludes that the integrated supply network eliminates the need for interfacing of individual networks and enables simultaneous planning of many components as well as forward planning of supply components in global supply chain operations. It also shows that the integrated approach is capable of providing visibility, flexibility, and maintainability for further improvement in the supply network environment.  相似文献   

5.
This paper proposes a new management mode named the persistent integration and innovation management mode to satisfy the requirements by the fast development at oilfields. Taking engineering philosophy as the guidance and technical innovations in petroleum production engineering as the breaking point, the management mode combines long term production practice at oilfields with modern management methods. The management mode integrates intellectuals, techniques, capital, and information and so on to accomplish global optimization of resource configuration. Sets of new techniques, new methods, new technologies and new equipment in petroleum production engineering have been proposed under the guidance of the management mode, achieving great social and economic benefits.  相似文献   

6.
基于元数据的制造资源编码信息集成研究   总被引:1,自引:0,他引:1  
为了解决航空企业制造资源代码不统一带来的诸多问题,开发了代码登记系统.为了实现其与企业系统的集成,本文设计确定了统一编码信息模型和基于元数据的编码信息集成框架,并且通过代码登记系统与某企业ERP系统的编码模块的集成验证了该框架的有效性.  相似文献   

7.
Research on competitive pressure plays an important part in understanding a firm’s behaviour in its changing environment. This paper provides an empirical contribution to the knowledge of the relationship between competitive pressure and internal information integration in this area by focusing on manufacturer internal information integration. The findings show that the degree of manufacturer internal information can be explained by the competitive strength of the largest firm in the industry. From a management perspective, the results indicate the need to regard the competitive landscape as an additional lever of manufacturer internal information sharing.  相似文献   

8.
Because most approximation functions employed in meshfree methods are rational functions with overlapping supports, sufficiently accurate domain integration becomes costly, whereas insufficient accuracy in the domain integration leads to suboptimal convergence. In this paper, we show that it is possible to achieve optimal convergence by enforcing variational consistency between the domain integration and the test functions, and optimal convergence can be achieved with much less computational cost than using higher‐order quadrature rules. In fact, stabilized conforming nodal integration is variationally consistent, whereas Gauss integration and nodal integration are not. In this work the consistency conditions for arbitrary order exactness in the Galerkin approximation are set forth explicitly. The test functions are then constructed to be variationally consistent with the integration scheme up to a desired order. Attempts are also made to correct methods that are variationally inconsistent via modification of test functions, and several variationally consistent methods are derived under a unified framework. It is demonstrated that the solution errors of PDEs due to quadrature inaccuracy can be significantly reduced when the variationally inconsistent methods are corrected with the proposed method, and consequently the optimal convergence rate can be either partially or fully restored. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   

9.
In the view of engineering philosophy, the mining engineering is a dynamic operating process of ferrous material flow, in which the ferrous material flow is processed orderly through a series of continual coordinated procedures. It is also a process of discarding the dross, selecting the essential, and extracting the original metal. The object of management is to fulfill the multi-objective optimization. The proportion of lean ores in iron ore resources is 82% in the world and even 97% in China but their utilization is very low. Aiming at the bottleneck and weakness of China’s resource development, this paper analyzes and plans the mining engineering system as a whole based on the ideas and methods of system theory and engineering philosophical thinking. And the paper proposes the “grade decision-based multi-system integration” engineering management mode, which considers the relationship between engineering and environment and complies with the natural law. In the mode, the mining engineering, including geologic mining, ore blending, concentration and pelleting, can be viewed as a whole and the geological grade, mined ore grade, feed grade, concentrate grade and feed grade of blast furnace can be considered comprehensively. The mode reflected the overall structural optimization idea, realized the analysis, coordination and optimization among the multiple functions and processes, and thus drove the overall efficient and profit optimization throughout the processing flow. The establishment and the application of the “grade decision-based multi-system integration” mode have solved the lean iron ores exploitation problem and supported the “self-sufficiency” resource strategy.  相似文献   

10.
在实际工程结构动力反应分析中,往往由于结构型式十分复杂,常用的两种直接积分方法,即显式积分方法和隐式积分方法,在使用中都存在着一定的局限性,如何将这两种积分方法合理有效地结合起来,是一个十分有意义的研究课题。针对实际工程问题中整体结构计算时间步长的选择往往受局部区域的材料特性、尺寸大小等因素影响的这一现象,提出了一种对结构局部区域进行隐式积分、对其余区域进行显式积分的工程实用的显隐式数值积分方法,这种积分格式相对于显式积分格式而言,能显著提高整体结构的计算速度。最后采用三个数值计算实例对这一方法进行验证。  相似文献   

11.
刘俊  董千里  李毅斌  李俊辉 《包装工程》2013,34(11):117-120
从物流本身发展的角度,探讨了军事应急物流军民融合的 3 个层次:点融合、线融合和面融合,即军事应急物流基本要素融合、基本环节融合和应急物流供应链融合。 研究了各层的运行机制,认为点融合和线融合分别是单个或部分基本要素、基本环节的融合,其运作由军民各自应急物流体系完成;面融合是军民整条应急物流供应链融合,其运作由军民协作共同完成。 最后提出了军事应急物流军民融合实现的 4 条途径。  相似文献   

12.
Abstract

This paper presents an unconditionally stable implicit algorithm for the direct integration of a linear structural dynamic equation of motion. The algorithm is based on two simultaneous difference equations and a weighting factor G for solving displacement at the next time step. Unconditional stability is proven for the weighting factor G in the range from –0.466 to 0.140 in all undamped and damped cases. The unconditionally stable range of G can be extended, from –1.0 to 0.333, for certain types of structure. The amplitude decay and period variation are used as the basic parameters to compare the accuracy of the present algorithm with various other integration methods. A spring‐mass‐dashpot model is applied to illustrate the algorithm for transient and quasi‐static analyses.  相似文献   

13.
面向产品创新知识集成的模型及机制   总被引:1,自引:0,他引:1  
欧光军 《工业工程》2008,11(1):40-43
构建了知识过程与产品创新过程相融合的知识集成模型,具体从知识活动、知识内容和知识主体的角度分析了知识集成的MSSI、SCEI和ITOI模型,分析了该模型的特点;讨论了产品创新知识集成机制.  相似文献   

14.
全生命周期产品和过程模型集成技术研究   总被引:4,自引:0,他引:4       下载免费PDF全文
制造业的产品和过程集成技术体现在各个不同的层面,为此,研究了全生命周期产品和过程模型的集成技术。采用面向对象方法,构建全生命周期虚拟产品模型,对全生命周期的产品信息进行表达,并对全生命周期的涵义进行阐述。虚拟产品模型由实体对象和联系对象组成,它是一个动态模型,在产品全生命周期中不断进化。通过面向对象Petri网模型(OPN),描述产品全生命周期的各种过程。在虚拟产品模型和OPN模型的基础上重点讨论产品模型和过程模型的集成技术,并结合实例进行研究。产品和过程模型集成为产品信息的重用和追溯提供支持。  相似文献   

15.
New theoretical ideas and developments describing the fundamental underlying basis for formulating a general family of time discretization operators for first‐order parabolic systems emanating from the framework of a generalized time weighted philosophy are first presented which can be broadly classified as pertaining to Type 1, Type 2 and Type 3 family of time discretization operators. As a consequence, the evolution including the clear distinction and the bridging of the relationships between time operators termed as integral operators to the so‐called integration operators in time are theoretically developed and demonstrated. The present developments seem to not only provide avenues leading to new algorithms for transient analysis but also provide generalizations and framework to recover a wide variety of existing algorithms. Consequently, under the umbrella of the present framework, a variety of plausible new approaches for generating Nth‐order accurate time discretization operators from approximations introduced to Type 1 integral operators in time are first described followed by the developments systematically leading to Type 2 time discretization operators, and subsequently to a wide class of Type 3 time integration operators including the recovery of a variety of known existing time integration operators which can be uniquely identified by Discrete Numerically Assigned (DNA) algorithmic markers. Of the various developments, of noteworthy mention and emphasis here are a new family of L‐stable Nth‐order Integration Operators (LNInO) of Type 2 for transient computations. Subsequently, some practically useful second‐order forms are specifically illustrated and highlighted. The stability and accuracy characteristics are also described for a variety of generated algorithms applicable for transient heat transfer computations. Although the primary focus is on the theoretical developments encompassing linear operators, some simple numerical examples are finally demonstrated to merely illustrate the salient features of the proposed developments. Copyright © 1999 John Wiley & Sons, Ltd.  相似文献   

16.
This work introduces a time‐adaptive strategy that uses a refinement estimator on the basis of the first Frenet curvature. In dynamics, a time‐adaptive strategy is a mechanism that interactively proposes changes to the time step used in iterative methods of solution. These changes aim to improve the relation between quality of response and computational cost. The method here proposed is suitable for a variety of numerical time integration problems, for example, in the study of bodies subjected to dynamical loads. The motion equation in its space‐discrete form is used as reference to derive the formulation presented in this paper. Our method is contrasted with other ones based on local error estimator and apparent frequencies. We check the performance of our proposal when employed with the central difference, the explicit generalized‐ α and the Chung‐Lee integration methods. The proposed refinement estimator demands low computational resources, being easily applied to several direct integration methods. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   

17.
薛澄岐  王琳琳 《包装工程》2021,42(20):112-124
目的 对人机融合的研究现状进行了梳理和分析,旨在为智能人机系统研究提供理论支撑.方法 从人机交互和人工智能的概念出发,结合多通道信息融合、人机融合认知决策机制、生理测量和人机融合协作模式等研究,对人机融合和智能人机交互的研究现状、研究热点与趋势进行了分析和归纳.结果 智能机器的信息处理逻辑与人类之间的沟通障碍,抑制了人工智能技术对人机资源整合的工效学意义,人机融合的研究促进了人工智能技术与人机交互的精准合作.结论 智能人机系统中,人、机、物理环境的融合不足是当前学界面临的挑战.人机融合研究应以感知识别、多通道信息融合、认知决策为着力点,帮助机器有效学习、理解、预测人类交互意图,探寻人机对话协作模式的影响要素.人机融合的群体智能对未来人机交互发展有着举足轻重的意义,通过多模态生理融合与自适应的可视化表征机理研究建立认知效率和可视化表征的联系,根据生理指标的变化构建意图空间并指导人机融合协作模式的研究.  相似文献   

18.
As promising candidates for energy-storage devices,supercapacitors (SCs) have attracted considerable attention because of their unique features,such as their high power density,outstanding rate capability,excellent cycling performance,and safety.The recent boom in portable electronic devices requires high-performance SCs that are flexible,simplified,thin,and integrated.Tremendous efforts have been directed towards the design and integration of planar microSCs (MSCs) based on different active electrode materials by various methods.This review highlights the recent developments in the device design of flexible planar MSCs and their integration with other electronic devices.The current challenges and future prospects for the development of flexible MSCs are also discussed.  相似文献   

19.
A standardized formal theory of development/evolution, characterization and design of a wide variety of computational algorithms emanating from a generalized time weighted residual philosophy for dynamic analysis is first presented with subsequent emphasis on detailed formulations of a particular class relevant to the so‐called time integration approaches which belong to a much broader classification relevant to time discretized operators. Of fundamental importance in the present exposition is the evolution of the theoretical design and the subsequent characterization encompassing a wide variety of time discretized operators, and the proposed developments are new and significantly different from the way traditional modal type and a wide variety of step‐by‐step time integration approaches with which we are mostly familiar have been developed and described in the research literature and in standard text books over the years. The theoretical ideas and basis towards the evolution of a generalized methodology and formulations emanate under the umbrella and framework and are explained via a generalized time weighted philosophy encompassing single‐field and two‐field forms of representations of the semi‐discretized dynamic equations of motion. Therein, the developments first leading to integral operators in time, and the resulting consequences then systematically leading to and explaining a wide variety of generalized time integration operators of which the family of single‐step time integration operators and various widely recognized and new algorithms are subsets, the associated multi‐step time integration operators and a class of finite element in time integration operators, and their relationships are particularly addressed. The generalized formulations not only encompass and explain a wide variety of time discretized operators and the recovery of various original methods of algorithmic development, but furthermore, naturally inherit features for providing new avenues which have not been explored an/or exploited to‐date and permit time discretized operators to be uniquely characterized by algorithmic markers. The resulting and so‐called discrete numerically assigned [DNA] markers not only serve as a prelude towards providing a standardized formal theory of development of time discretized operators and forum for selecting and identifying time discretized operators, but also permit lucid communication when referring to various time discretized operators. That which constitutes characterization of time discretized operators are the so‐called DNA algorithmic markers which essentially comprise of both (i) the weighted time fields introduced for enacting the time discretization process, and (ii) the corresponding conditions these weighted time fields impose (dictate) upon the approximations (if any) for the dependent field variables in the theoretical development of time integrators and the associated updates of the time discretized operators. Furthermore, a single analysis code which permits a variety of choices to the analyst is now feasible for performing structural dynamics computations on modern computing platforms. Copyright © 2001 John Wiley & Sons, Ltd.  相似文献   

20.
The purpose of this work was to study the packaging supplier and the integration of integrating packaging suppliers into the supply and demand chain (SDC). The packaging industry has been analyzed using a structured market analysis, and the companies studied have been positioned in an integration model for packaging suppliers. In addition, case studies were conducted to study the development of the packaging industry and its integration within the SDC in the Scandinavian region. The analysis shows that there are gaps in the business relations between the packaging companies studied and the SDC. Most of the packaging suppliers were not integrated into the SDC. Valuable information, available in the network, seldom reaches the packaging supplier who holds the knowledge necessary to create and offer innovative packaging solutions. The article provides an empirical exploration into the field of packaging, logistics and SDC integration and an original conceptual framework that could serve as a theoretical framework for future research work applied in the packaging industry and an interesting business model to the increase understanding of packaging supply chain integration. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   

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