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1.
Many refinements of Nash equilibrium yield solution correspondences that do not have closed graph in the space of payoffs or information. This has significance for implementation theory, especially under complete information. If a planner is concerned that all equilibria of his mechanism yield a desired outcome, and entertains the possibility that players may have even the slightest uncertainty about payoffs, then the planner should insist on a solution concept with closed graph. We show that this requirement entails substantial restrictions on the set of implementable social choice rules. In particular, when preferences are strict (or more generally, hedonic), while almost any social choice function can be implemented in undominated Nash equilibrium, only monotonic social choice functions can be implemented in the closure of the undominated Nash correspondence.  相似文献   

2.
This paper addresses the integration of the planning decisions concerning inbound logistics in an industrial setting (from the suppliers to the mill) and outbound logistics (from the mill to customers). The goal is to find the minimum cost routing plan, which includes the cost-effective outbound and inbound daily routes (OIRs), consisting of a sequence of deliveries of customer orders, pickup of a full truck-load at a supplier, and its delivery to the mill. This study distinguishes between three planning strategies: opportunistic backhauling planning (OBP), integrated inbound and outbound planning (IIOP) and decoupled planning (DIOP), the latter being the commonly used, particularly in the case of the wood-based panel industry under study. From the point of view of process integration, OBP can be considered as an intermediate stage from DIOP to IIOP. The problem is modelled as a Vehicle Routing Problem with Backhauls, enriched with case-specific rules for visiting the backhaul, split deliveries to customers and the use of a heterogeneous fleet. A new fix-and-optimise matheuristic is proposed for this problem, seeking to obtain good quality solutions within a reasonable computational time. The results from its application to the wood-based panel industry in Portugal show that IIOP can help to reduce total costs in about 2.7%, when compared with DIOP, due to better use of the delivery truck and a reduction of the number of dedicated inbound routes. Regarding OBP, fostering the use of OIRs does not necessarily lead to better routing plans than DIOP, as it depends upon a favourable geographical configuration of the set of customers to be visited in a day, specifically, the relative distance between a linehaul that can be visited last in a route, a neighboring backhaul, and a mill. The paper further provides valuable managerial insights on how the routing plan is impacted by the values of business-related model parameters which are set by the planner with some degree of uncertainty. Results suggest that increasing the maximum length of the route will likely have the largest impact in reducing transportation costs. Moreover, increasing the value of a reward paid for visiting a backhaul can foster the percentage of OIR in the optimal routing plan.  相似文献   

3.
This article describes the first fully integrated material planning system to facilitate the management of a remanufacturing facility. A number of firms are already engaged in this activity. They remanufacture automobile, truck, and other vehicle components, like starters, alternators, transmissions, and so forth. These firms take in used components, disassemble them, and assemble saleable products from the good parts they find. There is considerable uncertainty in the supply of used components, the good parts in those components, and the demand for remanufactured products. Our system is based on material requirements planning logic, something that many firms in the industry are already familiar with. Meetings with experts in the industry were used to set the parameters of the system and evaluate its approach.  相似文献   

4.
This paper looks at the developing scene in the U.K., with gloom at home and turmoil overseas: and with a new government committed to non-intervention in industry; to exposure of labour and of products to market forces and to avoidance of detailed economic planning. It examines the reality of party stances over the general field of government/industry relations and over cuts in public expenditure in both central and local government.Finally it examines the role of the professional planner at times of maximum uncertainty: and concludes that given a clear mind and a cool head the planner may be a unique stabilising influence at the heart of the company's affairs.  相似文献   

5.
Aggregate production planning decisions are inter mediate range decisions that can have a significant impact on both productivity and profitability. In this paper, we examine an interactive computer-based method that provides decision support for the aggregate planner. The proposed approach combines the judgement of the planner with the optimization of subproblems to arrive at an effective solution for multi-family aggregate production planning problems. In the interactive approach, the planner exercises direct control over sensitive workforce levels and production capacities. A network flow sub-problem solver is used to generate optimal production plans and inventory levels given the user-specified production capacities. Decision aids are provided to help the planner achieve a cost-effective solution that is consistent with judgement concerning workforce levels. Computational testing on five test problems indicates that very cost-effective solutions can be obtained. The results of applying the interactive method to a real-world problem are also reported.  相似文献   

6.
MF Cantley 《Omega》1973,1(1):55-77
This paper is about corporate planning, seen primarily but not exclusively from the viewpoint of operational research. The reasons for the rise of interest in corporate planning are examined, as are the contributions which O.R. has made or can make to corporate planning problems. An abstract discussion of these problems concentrates on those posed by increasing “connectedness” in the environment. After comparing the responses of the “commonsense manager”, the model-oriented operational researcher, and the cybernetician, the question is posed: “How can the operational researcher or planner enhance the adaptive capability of his organization?” A case study illustrates one possible form of solution, the “modular” approach; and another, the “zoom-lens” is outlined. The relevance of global system modelling to the widening problems of the corporate planner is also considered, and related to the concepts previously discussed.  相似文献   

7.
Traditional production control systems based on the manufacturing resource planning concept do not sufficiently support the planner in solving capacity problems, ignore capacity constraints and assume that lead times are fixed. This leads to problems on the shop floor, that cannot be resolved in the short term. This paper focuses on solving these capacity problems by improving capacity planning at the material requirements planning MRP level through integration of MRP and finite capacity planning. This results in a planning method for simultaneous capacity and material planning. The planning method is based on a new and more accurate primary process model, giving the planning algorithm more flexibility in solving capacity problems. The algorithm is based on advanced scheduling techniques and uses aggregated information, thus combining speed and accuracy. The algorithm is designed to use the available flexibility: alternative routeings, safety stock, and replanning of production orders and requirements. This paper also discusses such related issues as robustness, memory and the role of the human planner.  相似文献   

8.
Roger Mortimore   《Omega》1973,1(6):711-718
A corporate planning system makes measurement demands on an organisation which it may not have met before. This paper describes these in the context of corporate planning in local government, and discusses some typical examples, especially as far as needs for services and the effects of providing them are concerned. It also deals with the extent to which choices can be measured, and with the constraints that a real-time decision system puts on the planner.  相似文献   

9.
A key point in considering strategic planning is that it is not forecasting. The future is unpredictable and is not a product of the past. This low opinion of forecasting has gained in influence recently. But such an approach creates a dilemma for the strategic planner. He needs to take into account potential future forces--but he can only do this with inadequate means. Forecasting methods, however, can suggest trends and it is possible to reduce the number of possible futures to a manageable number. This is, in effect, creating scenarios. The concept of using alternative scenarios in planning was popularized some 20 years back. The proviso was made that they should not be interpreted as forecasts. The methods have proved highly flexible and include the consensus technique, the iteration-through-synopsis technique, and the cross-impact method. Various studies using one or more of these have been implemented, perhaps the best known being by Meadows and by Mesarovic. These have been based on the so-called 'hard' method, using computers. 'Soft' methods are based more on the mind and use psychology and sociology, the most familiar being the Delphi method. A somewhat more sophisticated version is Cross-Impact Analysis.  相似文献   

10.
Strategic planning is now a large and diverse activity practised in many different kinds of organizations. This article provides an overview of the field with a summary of the five main schools of thought each with its own business philosophy and a range of practical approaches and techniques. These basic styles are concerned with planning as a central control system, a framework for innovation, an organizational change process, a political activity, and a way of exploring the future. Most planning systems have a dominant style or focus and this emphasis needs to be adjusted in response to changes which are occurring continually in the organization and in the external environment. The article is designed to help the senior manager or corporate planner to assess the state of planning in his organization and to see where there are important gaps in the enterprise's capability for planning which might be filled by the launching of new initiatives. The article also offers an agenda of approaches for consideration by the executive who wishes to move his enterprise from a conventional 5-year planning and budgeting system towards a more comprehensive process of managing organizational change and development.  相似文献   

11.
The increasing complexity of socio-economic systems has increased the need for planning while at the same time making planning more difficult. Planning in a changing environment for an uncertain future presents the planner with a dual challenge. He must not only identify the forces behind changing circumstances but must also help wean decision-makers from their dependence on single-line forecasts.  相似文献   

12.
To undertake any kind of realistic planning activity, it is useful to have a long-term environmental forecast which provides the planner with an overall perspective. The planner will be functioning over the next decade in a very dynamic, complex and challenging political, economic, technological and social environment, and will require very effective planning efforts to cope with such changing environment. This article presents an approach and methodology that a planner could use in his/her organization's planning process. To the best of our knowledge, very few organizations—profit and non-profit oriented—undertake a formal long-term environmental forecast. This article might encourage several planners to examine this area of long range planning in their respective organizations. The long- term environmental forecasting approach presented in this article could be applied by planners in all types of organizations—small or large, profit oriented or non-profit oriented, old or new. This article, however, is based on a study which the authors did for a non-profit organization.  相似文献   

13.
Firms can benefit by developing and using aggregate production plans. However, reports of ongoing production planning applications are rare. The complexity of production planning models has been cited as one of the reasons that firms do not develop formal production plans. This study was conducted to determine if a simple model, trial-and-error on a spreadsheet, could be used to produce cost-effective production planning solutions. Results indicate that good solutions can be obtained using this method. Furthermore, solutions tend to improve as the knowledge of the production planner increases and as time spent developing solutions increases. In addition, experience at producing spreadsheet-based solutions can translate into lower cost solutions for more complex problems while using less time for analysis. These findings indicate that spreadsheets can be effective decision aids for developing production planning solutions. By coupling the power and simplicity of a spreadsheet modelling package with the trial-and-error approach to production planning, model complexity should no longer be cited as a reason for not developing and using formal aggregate production plans.  相似文献   

14.
Capacity planning is instrumental in production planning as the variability witnessed in construction projects complicates the planner’s role in achieving a balance between weekly task load and available resources. The purpose of this article is to assess the effects of capacity planning on a project’s time and cost performance and to inform planners on the pitfalls of uninformed capacity planning. A simulation model is developed to test several project scenarios against different capacity planning methods. Cost, time and planning quality measures are developed to track project’s performance throughout the construction period. Results show that the planner’s choice of capacity planning method and the type of project both affect a project’s cost and duration. Interestingly, informed planners who are aware of a project’s characteristics are able to achieve the best balance between weekly load and capacity. They are able to reduce incurred costs wasted on idle resources without significantly affecting the construction period.  相似文献   

15.
One of the basic functions of an MRP system is to issue rescheduling messages that urge the planner tospeed up or slow down open orders. It seems in practice that these messages are not used at all by planners. This is mostly due to the inaccuracy of MRP, that more or less ignores safety time, safety stocks and lotsize flexibility in the calculation of reschedule-in messages. Reschedule-out messages are usually ignored because planners do not see the value of the message. Other reasons for not adhering to rescheduling messages are a lack of maintenance of MRP parameters or simply the wrong use of the MRP function. In the future, MRP rescheduling functionality will be used even less than today, due to the changing role of MRP within the planning framework. With the uprise of finite capacity scheduling packages, MRP is being pushed one level upward in the planning hierarchy. This means that rescheduling functionalities for the short term will become completely obsolete in MRP systems.  相似文献   

16.
Alan H Kvanli 《Omega》1980,8(2):207-218
Financial planners within industrial organizations are often given the impossible task of formulating a multi-year financial plan which is severely over-constrained. As the planner attempts to meet one objective another variable (or ratio of variables) becomes unacceptable and he is faced with the familiar ‘balloon squeezing’ effect. The problem is one of multiple conflicting objectives (goals) hence lends itself very well to a goal programming method of solution. This approach provides a powerful ‘what-if’ device for the financial planner and allows him to arrive at a satisfactory solution by examining the various trade-offs among the conflicting goals. To be an effective and usable tool, the individual goals are not assigned a priority coefficient as is typical of most goal programming applications. Rather, the planner can reflect his priorities in the manner in which he performs the subsequent what-if analyses. Also, a more flexible penalty function is introduced allowing the planner to assign a more realistic set of penalities which vary in severity over a specified range. Methods of implementing this concept are discussed which overcome the problems created by the immense storage requirements and the necessity of assigning the various penalties.  相似文献   

17.
A major complication in the planning of facility systems and in the analysis of their locational configurations is the fluctuating nature of the systems they serve. Locations identified now, based on current conditions, may be undesirable in the future, and those based on future conditions may be undesirable now. This paper proposes a general methodology using multiobjective analysis to plan public-sector facility systems operating in a dynamic environment. A model is developed for the specific case of locating emergency services and an illustrative example is presented.  相似文献   

18.
In recent years there has been a good deal of discussion amongst planning specialists and academics about the gap which exists between the theory of planning as set out in journals and textbooks, and the practice of planning in private and public organizations. Planners are continually complaining about the resistance to planning by top management and operating managers in divisions and departments.In this article the author aims to produce a reconciliation between theory and practice and to discuss what alternative strategies are open to planners in devising planning systems for their organizations.He suggests that the problem has its origin in the fact that corporate planning theory was first developed by management scientists as a total systems approach. Corporate planners have failed to sell an integrated planning system either as programme budgeting or as corporate planning. Research suggests that a management team can only adopt and implement a comprehensive planning system in very special circumstances, e.g. when the organization's survival is threatened, a new management team has been appointed and the staff of the organization are ready to accept radical change.In normal circumstances the planner is wrong to advocate a ‘root and branch’ solution. He must diagnose the planning needs of the organization and his objective must be not merely to establish a particular planning procedure but rather to discover how he can best improve the quality of management decisions.Recent studies on strategy formation indicate that the introduction of a formal planning procedure is only a partial answer to the problem of improving the quality of management decisions.The paper reviews various approaches to planning and considers how they relate to organizations with different strategic problems, with differing organization structures and various management styles.  相似文献   

19.
Strategic planning and decision making in the face of uncertainty have always presented a serious challenge to top management, but the present scale of uncertainty is unprecedented. Decision makers used to be able to rely on the past to predict the trends of the future. Now they are increasingly being forced to make important decisions that depend upon highly uncertain external factors for which the past offers little guidance. In all areas of business and government, there is a vital need to understand and implement procedures that enable decision makers to deal more effectively with uncertainty for planning and allocating their organizations' resources.Because of differences in their social, political and economic environments, European and Japanese managers are today affected by many acute areas of uncertainty— such as industrial democracy, floating exchange rates, changing social and political values, growing environmental awareness, government regulation, technological change, pollution control regulation, energy cost, and raw material availability—earlier than their counterparts in the U.S.A. These uncertainties affect not only private sector manufacturing industries, but also financial and service industries as well as nationalized industries and government organizations.This article shows how ineffective methods of dealing with uncertainty can lead to serious mistakes with costly consequences. The cost of overconfidence and people's natural but futile tendency to ignore or to try to eliminate uncertainty is illustrated by the crises seen recently in the world steel and shipbuilding industries. The article then demonstrates how decision analysis procedures that focus directly on the major decision points in the strategic plan enable executives not only to include uncertainty directly in their strategic planning, but also to increase their understanding of the decision process and their ability to communicate the results to others.  相似文献   

20.
Most planning strategies include a goal development phase, yet very little concrete information is available in the program planning literature to help the planner know what a goal is or should be. Goals play an important role in systems theory and the theory offers a structure for the careful defining of goals. This article identifies the function of goals in systems as being the facilitation of evaluation and control. From this system functional analysis viewpoint, several specific characteristics of goals are derived and discussed.  相似文献   

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