JIT purchasing: attribute classification and literature review

To find critical JIT purchasing attributes for manufacturing industry, 56 refereed articles are reviewed. These articles are categorized as conceptual, case and empirical studies. Thirty-four attributes are thus identified. An input-output model is developed to classify these attributes. The inputs to JIT purchasing environment consists of buyer, supplier and joint buyer-supplier actions with 13, six and six attributes, respectively. The interaction between these attributes leads to the JIT purchasing environment. Output of this environment consists of nine attributes. By using the frequency of citation of an attribute as a measure of its importance, consensus is found among conceptual and case studies regarding those attributes of JIT purchasing considered critical. However, many of these attributes have not been investigated empirically, while others have not been rigorously examined. Common supplier evaluation criteria are identified. Benefits and problems with JIT purchasing implementation are discussed. Analysis suggests the need for comprehensive and statistically rigorous empirical studies.     

An approachto the machine layout problem in a cellular manufacturing environment

The model of the machine layout problem MLP in a cellular manufacturing environment attains additional dimensions as it should satisfy the qualitative interconnections between the machines and the location restrictions of an existing factory environment. A new MLP model based on merging pre-emptive goal programming and simulated annealing has been developed for machine layout in cells. This model seeks to find feasible solutions by addressing practical issues of implementation as well as reducing the total travel distances for parts between machines. The new model can also be applied to facility layout problems FLP . The computational work is demonstrated by applying the model to problems of both quantitative and qualitative types, and has produced encouraging results. This model is particularly attractive for layout problems with realistic goals and constraints. To show the performance of the model in handling real-world problems, a practical example has been introduced and solved using the proposed model.     

Development of demand pull type control methods: The design of block action production control methods to reduce throughput time and improve supply chain synchronization

In this paper the implementation of time based manufacturing strategies and pull type control systems in an organization manufacturing electrical switchgear built to customers individual requirements are discussed in detail. The concept of block control to synchronize the production time of all internally and externally sourced components and materials is also introduced in an attempt to simplify production control methods and reduce throughput time. Savings in time and cost are described during a twenty months period of restructuring. Foundations were laid for a second objective which is an attempt to gain some linkage between throughput time reduction and resultant production costs.     

Selecting IT applications in manufacturing: a KBS approach

The use of the right type of Information Technology (IT) applications or manufacturing systems is expected to usher in a competitive advantage. Selection of the right type of IT application is, however, a challenging task. When a company, with a given dominant process structure, emphasizes two or more competitive priorities, such as quality, product flexibility, etc., an unaided manager faces a complex decision problem in choosing from alternative IT applications available in the areas of product design through distribution. In this paper, we present a Knowledge Based System (KBS) that would assist managers with the identification of IT applications that are consistent with both the competitive priorities and the process structure. Validation of the system illustrates that its performance is consistent with the human experts, and it has the potential to facilitate effective and swift decision-making in the selection of appropriate IT applications that best match an organization's manufacturing strategy.     

Lead time adjustment through scrap management

In a discrete parts manufacturing environment, it is necessary to compensate for the decreasing planned batch size resulting from production of scrap (defectives) in the production line, by increasing the planned production volume. This calls for a revision in the initially computed manufacturing lead time (MLT). A survey of the literature reveals that although issues related to product quantity regeneration have been studied in detail, little has been done to assess the impact on manufacturing lead times. This paper discusses the impact of scrap on manufacturing lead time in a shop with an intermittent-flow, bath-oriented, discrete-parts manufacturing environment, producing make-to-stock items.     

Survey of resource allocation methods for distributed manufacturing systems

Distributed manufacturing systems are more flexible in their arrangement and use of their resources. This permits a more dynamic and opportunistic allocation of manufacturing resources to work elements than is possible with today's centralized allocation systems. However, unlike solving the problem from a single solver view, there is no absolute control or tight coordination over how and when to decompose the problem, when to undertake a solution or the procedure for verifying consistency. Such activities will largely be left to the distributed entities to decide either individually or jointly. As a consequence the resulting allocations may suffer and induce myopic behaviour lacking in stability and regularity in the performance of the total system. Thus, the issues connected with solving the problem often move beyond the pure algorithmic focus of computation to include how the problem is decomposed, how or to whom it is assigned, and the organization for solving the subproblems, strategies used for resolving conflicts, the manner in which communication is conducted, etc. These issues, in fact, highlight the holistic nature of the solution and are used here as parameters to compare and contrast the approaches reported in the literature.     

Impact of Information Technology Integration and Lean/Just‐In‐Time Practices on Lead‐Time Performance*

Managers seeking to improve lead‐time performance are challenged by how to balance resources and investments between process improvement achieved through lean/just‐in‐time (JIT) practices and information technology (IT) deployment. However, extant literature provides little guidance on this question. Motivated by both practical importance and lack of academic research, this article examines empirically the relationships among interfirm IT integration, intrafirm IT integration, lean/JIT practices, and lead‐time performance using data from IndustryWeek's Census of Manufacturers ( IndustryWeek, 2006 ). The results provide several new insights on the relationship between IT integration and lean/JIT practices. First, the study confirms that implementing lean/JIT practices significantly reduces lead time. Second, lean/JIT practices mediate the influence of IT integration on lead‐time performance. This suggests that process improvements that result from lean/JIT practices are important contributors to the success of IT integration. Even companies that have experienced success in reducing lead time through lean/JIT practices may benefit from IT integration practices such as those embodied in enterprise resource planning systems. The findings provide managers with empirical evidence and a theoretical framework on the balance between lean/JIT and IT for effecting improvement in lead‐time performance, thus offering practical guidance on this important question. Future research is needed to extend the lean/JIT practices in this study to supply chain practices and explore the relationship between supply chain practices and IT integration.     

基于服务网络与制造网络互动的制造型集群超网络研究

在传统制造业集群基础上发展服务型制造业是当前产业界和学术界关注的热点问题。该文针对集群超网络中服务网络和制造网络如何相互作用的问题,以服务水平和产品附加值为决策变量,从成本与收益的角度,引入偏好系数,建立了多目标最优决策模型,并运用变分不等式理论,得到洽合的服务网络和制造网络的流,发现了超网络的均衡状态。最后,提出了研究服务网络和制造网络互动关系的实际意义,以及今后的研究方向。     

6西格玛：中国企业变革的路径选择

历时近30多年的中国国企改造给人们已展现出一幅亮丽的图景。到2010年初止，国企的产值由过去的90％变成50％左右。研究发现：在这些改制的企业中。有的转制成了私人企业．有的变成了合资企业。其中，业绩较理想的多数还是合资企业。那些成功改制后的合资企业是通过什么样的管理手段和路径使其效率大增？通过大量案例分析发现：6西格玛和与其共生的精益生产等现代生产管理方式是其变革的路径选择。     

智能化办公空间的管线设计

智能化办公空间的管线系统是保障办公环境有效运行的关键 ,建筑师应该了解管线布置的方式、特点及其对建筑空间的影响。本文针对这一问题进行了简要的分析 ,并总结出建筑师在设计中应注意的要点