Showing papers on "Cost reduction published in 1991"

Long term cost of ownership: beyond purchase price (chip manufacture)

Abstract: An economic cost of ownership model is developed to estimate the total cost per wafer for a given process operation. The model incorporates fixed and variable costs and process tool specific as well as fab specific cost inputs. While all the variables can affect the final outcome, it is shown that the long-term cost per wafer for a given process is directly proportional to both mechanical throughput yield and defect densities. Wafer cost is also extremely sensitive to throughput, which affects both the fixed and variable cost components. Due to the nonlinear relationship of wafer cost and factors affecting equipment utilization capability, cost reduction through reliability improvement may be effective depending on where the nominal baseline points are located on the curves. Changes in inputs such as initial equipment costs or engineering support hours have less impact on the final cost per wafer since these variables affect only one cost component of the model. >

From a Seed to a Need: the Growth of Shape Memory Applications in Europe.

Abstract: A more systematic marketing research approach has finally revealed good ideas anticipating a market need for the use of shape memory alloys. The success of those new ideas, prototypes and applications are analysed in terms of “the value of the function”, defined as the importance of the function divided by the cost of providing the function. A high importance and/or a low cost of the function are thus the basic requirements for the successful introduction of shape memory applications. Attention is also paid to the way how the 4 P's, product, price, place, promotion (the marketing mix) are applied by the European companies. Those different items will be illustrated on the basis of some small-, medium- and large-scale applications, used in different markets. The “to the point research”, fundamental and applied, on material properties as well as on manufacturing (cost reduction) is being discussed as the key factor to increase the function value.

Inspection Planningfor Deteriorating Structures Based on Sequential Cost Minimization Method

Abstract: The total cost minimization is the optimal criterion of decision making for design and maintenance of structures.In this study, a sequential cost minimization method and its consistent formulation are presented for the inspection planning problem of deteriorating structures. The method aims to find an optimal inspection strategy so that the total expected cost in the period between the present inspection and the next be minimum. The optimization variables are the inspection methods at the present inspection and the interval to the next inspection for the structure. The optimization is repeatedly carried out at every inspection.The optimal inspection methods are selected from the following five methods : 1) no inspection, 2) visual inspection, 3) mechanical inspection, 4) visual and conditional mechanical inspection, and 5) sampling mechanical inspection. The cost evaluation equation is developed for each inspection method, where the following cost items are included : inspection cost, repair cost, risk of member failure, risk of catastrophic failure and loss due to service suspension caused by scheduled and accidental system downs. The selection of suitable inspection interval for the structure is to be achieved by comparison of total expected costs evaluated for possible interval plans.The applicability of the proposed method is demonstrated through the numerical calculations by assuming a structural member set and a structure. Fatigue failure is considered as the deterioration damage of the members. Further, discussion is made on the value of the sequential cost minimization method, comparing with the optimal inspection strategy throughout the life time.

Control Concepts for Active Magnetic Bearings

Abstract: Active Magnetic Bearings (AMB) are becoming increasingly significant for various industrial applications. Examples are turbo-compressors, centrifuges, high speed milling and grinding spindles, vibration isolation, linear guides, magnetically levitated trains, vacuum and space applications. Thanks to the rapid progress and drastic cost reduction in power- and micro-electronics, the number of AMB applications is growing very rapidly. Industrial uses of AMBs leads to new requirements for AMB-actuators, sensor systems, and rotor dynamics. Especially desirable are new and better control concepts to meet demand such as low cost AMB, high stiffness, high performance, high robustness, high damping up to several kHz, vibration isolation, force-free rotation, and unbalance cancellation. This paper surveys various control concepts for AMBs and discusses their advantages and disadvantages. Theoretical and experimental results are presented.

Application of a design-build-team approach to low cost and weight composite fuselage structure

Abstract: Relationships between manufacturing costs and design details must be understood to promote the application of advanced composite technologies to transport fuselage structures. A team approach, integrating the disciplines responsible for aircraft structural design and manufacturing, was developed to perform cost and weight trade studies for a twenty-foot diameter aft fuselage section. Baseline composite design and manufacturing concepts were selected for large quadrant panels in crown, side, and keel areas of the fuselage section. The associated technical issues were also identified. Detailed evaluation of crown panels indicated the potential for large weight savings and costs competitive with aluminum technology in the 1995 timeframe. Different processes and material forms were selected for the various elements that comprise the fuselage structure. Additional cost and weight savings potential was estimated for future advancements.

Lessons learned for composite structures

Abstract: Lessons learned for composite structures are presented in three technology areas: materials, manufacturing, and design. In addition, future challenges for composite structures are presented. Composite materials have long gestation periods from the developmental stage to fully matured production status. Many examples exist of unsuccessful attempts to accelerate this gestation period. Experience has shown that technology transition of a new material system to fully matured production status is time consuming, involves risk, is expensive and should not be undertaken lightly. The future challenges for composite materials require an intensification of the science based approach to material development, extension of the vendor/customer interaction process to include all engineering disciplines of the end user, reduced material costs because they are a significant factor in overall part cost, and improved batch-to-batch pre-preg physical property control. Historical manufacturing lessons learned are presented using current in-service production structure as examples. Most producibility problems for these structures can be traced to their sequential engineering design. This caused an excessive emphasis on design-to-weight and schedule at the expense of design-to-cost. This resulted in expensive performance originated designs, which required costly tooling and led to non-producible parts. Historically these problems have been allowed to persist throughout the production run. The current/future approach for the production of affordable composite structures mandates concurrent engineering design where equal emphasis is placed on product and process design. Design for simplified assembly is also emphasized, since assembly costs account for a major portion of total airframe costs. The future challenge for composite manufacturing is, therefore, to utilize concurrent engineering in conjunction with automated manufacturing techniques to build affordable composite structures. Composite design experience has shown that significant weight savings have been achieved, outstanding fatigue and corrosion resistance have been demonstrated, and in-service performance has been very successful. Currently no structural design show stoppers exist for composite structures. A major lesson learned is that the full scale static test is the key test for composites, since it is the primary structural 'hot spot' indicator. The major durability issue is supportability of thin skinned structure. Impact damage has been identified as the most significant issue for the damage tolerance control of composite structures. However, delaminations induced during assembly operations have demonstrated a significant nuisance value. The future challenges for composite structures are threefold. Firstly, composite airframe weight fraction should increase to 60 percent. At the same time, the cost of composite structures must be reduced by 50 percent to attain the goal of affordability. To support these challenges it is essential to develop lower cost materials and processes.

Power plant operation and maintenance cost reduction through control system improvements

Abstract: Since 1973, operating and maintenance costs for power production plant have increased by 410%, while fuel costs have increased by 445%. Plant automation through improved instrumentation and control systems provides a cost-effective means to contain both operating and maintenance costs, as well as assisting in the more efficient utilisation of fuel by improving plant efficiency, manoeuvrability, reliability and availability.

Health financing in the poor countries : cost recovery or cost reduction?

Abstract: Many donor agencies have tended to view the problem of financing health care services in developing countries as a problem of cost recovery. Policy reforms based on this view have therefore focused on measures, such as user charges and insurance, intended to generate additional revenues to meet recurrent resource needs. However, the potential to actually reduce costs by eliminating waste in health systems has not been given adequate attention. The health care system in Mali represents a case study in the difficulties of providing effective care in poor countries. Households bear most of the burden of health financing, accounting for about 75 percent of total sectoral expenditures in 1986. Revenues from user charges represent only a small fraction of operating expenditures in government health facilities. Changing the present system so that cost recovery becomes a significant proportion of actual expenditures would be extremely difficult. However, realistic possibilities do exist for reducing the costs of pharmaceuticals. With improved drug management practices, Mali would not need additional external aid to make drugs available in its health units and dispensaries. This suggests that the therapy for improving public health services should be based primarily on cost reduction, not simply cost recovery. Such a focus on cost reduction is consistent with the goals of the Bamako Initiative.

An activity-based methodology for operations cost analysis

Abstract: This report describes an activity-based cost estimation method, proposed for the Space Exploration Initiative (SEI), as an alternative to NASA's traditional mass-based cost estimation method. A case study demonstrates how the activity-based cost estimation technique can be used to identify the operations that have a significant impact on costs over the life cycle of the SEI. The case study yielded an operations cost of $101 billion for the 20-year span of the lunar surface operations for the Option 5a program architecture. In addition, the results indicated that the support and training costs for the missions were the greatest contributors to the annual cost estimates. A cost-sensitivity analysis of the cultural and architectural drivers determined that the length of training and the amount of support associated with the ground support personnel for mission activities are the most significant cost contributors.

Balancing reliability and cost to choose the best power subsystem

Abstract: A mathematical model is presented for computing total (spacecraft) subsystem cost including both the basic subsystem cost and the expected cost due to the failure of the subsystem This model is then used to determine power subsystem cost as a function of reliability and redundancy Minimum cost and maximum reliability and/or redundancy are not generally equivalent Two example cases are presented One is a small satellite, and the other is an interplanetary spacecraft

Cost reduction technology for high-efficiency photovoltaics: Research issues and progress

Abstract: An overview is presented of the Department of Energy (DOE) photovoltaic program's research on III-V solar cells directed toward establishing the base of technology necessary to design lower cost production processes and improve the reliability of manufacturing projections. It is shown that cost reduction in the high-efficiency technologies requires a three-pronged attack. First, increasing the efficiency is still the most direct path to lowering the cost of photovoltaic (PV) modules, provided that the additional device sophistication does not add cost. The second prong is to improve the technologies for crystal growth. Production cost factors related to large-area uniformity, yield, process safety, and source utilization efficiency are inseparable from the more esoteric scientific issues such as thermal geometry, reaction chemistry, crystallographic orientation effects, spinodal decomposition, and interdiffusion. Finally, an improved technology and new concepts are needed to eliminate the cost of consuming a crystalline substrate. >

On setup cost reduction in the economic lot-sizing model without speculative motives

Abstract: An important special case of the economic lot-sizing problem is the one in which there are no speculative motives to hold inventory, i. e., the marginal cost of ]n'oducing one unit m some period plus the cost of holding it until some future period is at least the marginal production cost in the latter period. It is already known that this special case can be solved in linear time. In this paper we study the effects of reducing all setup costs by the same amount. It turns out that the optimal solution changes in a very structured way. This fact will be used to develop faster algorithms for several problems that can be reformulated as parametric lot ..,.sizing problems. One result, w07,th a separate mention, is an algorithm for the so called dynamic lot sizing problem with learning eifects in setups. This algorithm has a complexity that is of the same order as the fastest algorithm known so far, but it is valid for a more general class of models than usually considered, economic in reduction cost of algorithms, computational problem; Dynamic programming economic lot-sizing problem; Analysis lot-sizing parametric horizon: setup OR/MS subject classification: complexity: parametric economic /optimal control, applications: Inventory/production, planning lot-sizing model 1) Depart.ment of Mathemal.ics and Computing Science, Eindhoven University of Technology, P.O. [lox 513, 56UO MB Eindhoven, The Netherlands. 2) Economet.ric Tnstitul.e, Erasmns University Rotterdam, P.O. Box 1738, 3000 DR Rotterdam, The Netherlands; currently on leave at the Operations Research Center, Room E 40-16-1, Massach IIsetts Institute of Technology, Cambridge, MA 02139; financial support of the Netherlands Organization for Scientific Research (NWO) is gratefully acknowledged. o Introduction In 1958 Wagner and Whitin published their seminal paper on the "Dynamic Version of the Economic Lot Size Model", in which they showed how to solve the problem considered by a dynamic programming algorithm. It is well-known that the same approach also solves a slightly more general problem to which we will refer as the economic lot-sizing problem (ELS). Recently considerable improvements ha.ve been made with respect to the complexity of solving ELS and some of its special cases (see Aggarwal and Park, 1990, Federgruen and TzuI' , 1989, and Wagelmans, Van Hoesel and Kolen, 1992). Similar improvements can also be made for many extensions of ELS (see Van Hoesel, 1991). An important special case of ELS is the one in which there are no speculative motives to hold inventory, i.e., the marginal cost of producing one unit in some period plus the cost of holding it until some future period is at least the margina.l production cost in the la.tter period. It is already known that this special case can be solved in linear time. In this paper we study the effects of reducing all setup costs by the same amount. It turns out that the optimal solution changes ill a very structured way. This fact will be used to develop faster algorithms for several problems that can be reformulated as parametric lot-sizing problems. One result, worth a separate mention, is all algorithm for the so-called dynamic lot-sizing problem with learning effects in setups. This algorithm has a complexity that is of the same order as the fastest algorithm known so far, but it is valid for a more general class of models than usua.lly considered. The pa.per is orga.nized a.s rollows. In Section 1 we introduce the economic lot-sizing problclll without speculative motives and describe briefly a linear time algorithm to solve it. Section 2 deals with the parametric version of the problem in which all setup costs are reduced by the same amount. We will characterize how the optimal solution changes and present a linear time algorithm to calculate the reduction for which the change actually occurs. In Section 3 we discuss applications of the results of Section 2. Finally, Section 4 contains some concluding remarks. 1 The economic lot-sizing problem without speculative motives In the economic lot sizing problem (ELS) one is asked to satisfy at minimum cost the known demands for a specific commodity in a number of consecutive periods (the planning horizon). It is possible to store units of the commodity

Two level maintenance: How do you get there

Abstract: It is argued that proper partitioning analysis performed early in the conceptual design can rapidly identify and address significant support cost reduction opportunities for weapons systems designers. This is accomplished through design for two-level maintenance. The two-level maintenance requirement is defined and described in terms of its influence on the design process, and techniques are used to minimize weapon system logistics design issues are reported. These techniques and their benefits are described. The author concludes that there are three enabling technologies for meeting a two-level maintenance requirement: the conceptual design must be partitioned for minimum life-cycle costs, adequate built-in testing (BIT) must be designed into the hardware to provide the system maintainer with diagnostics capability to the candidate line-replaceable unit (LRU) level (from the partitioning analysis), and the candidate LRUs must be packaged for replacement in the user's forward operating environment. >

An analysis of setup cost reduction in a two stage system

Abstract: This paper investigates the impact of investing in setup cost reduction in a two stage manufacturing process. Closed form relationships are developed for the cases of investment in primary stage setup cost reduction, investment in finishing stage setup cost reduction, and simultaneous investment in setup cost reduction in both stages. Numerical results are presented which compare each of the models to the basic model. These results indicate that when investment in both stages is feasible, it is most effective to simultaneously invest in setup cost reduction. Failing this, the next best alternative is to invest in setup cost reduction in the finishing stage.

Energy management for rational electricity use-reducing cost and consumption at SECIL's Outao cement plant/Portugal

Abstract: Compania Geral de Cal e Cimento SARL (SECIL) is in the process of implementing a comprehensive and modern energy management project for rational use of electricity. A step in energy management implementation is the reduction of electric energy consumption (kWh/t). The preparation and first results of this new effort is the major topic. Emphasis is placed on extensive electronic energy metering and process data recording. These data are processed and refined to energy information that, in effect, uncovers hidden savings potentials. Energy information and related saving measures are introduced into daily organizational operating procedures and are backed up by a permanent energy management team. More than a 6% per annum electric energy cost reduction has already been achieved. Additionally, a 3 to 6% reduction of specific electric energy is a projected savings objective. >

Delivered Cost: The Impact of Technology

Abstract: How technology is used in logistics practice, and most specifically how it can be used to reduce delivered cost, is examined.

Advantages of process modeling as a key manufacturing tool to improve process efficiency and reduce costs

Abstract: The authors describe the utilization of simulation techniques to achieve significant manufacturing improvements for a typical DoD circuit card manufacturing facility. Although the information presented describes the process flow of printed wire boards through the manufacturing cycle it can be used for improving any process-oriented system. Also included is information on selecting the proper hardware and software for various environments, data requirements, locating and processing this data, setting up and manipulating the various simulation parameters, type of output, proper output analysis, applications to other situations, validation techniques, and actual results showing a 90% reduction of work in process and a 83% reduction in cycle time. The authors describe in detail the approach to use for implementation in any aerospace environment or similar business dealing with small demand requirements of a high product mix. >

Advanced composite structural concepts and material technologies for primary aircraft structures

Abstract: Structural weight savings using advanced composites have been demonstrated for many years. Most military aircraft today use these materials extensively and Europe has taken the lead in their use in commercial aircraft primary structures. A major inhibiter to the use of advanced composites in the United States is cost. Material costs are high and will remain high relative to aluminum. The key therefore lies in the significant reduction in fabrication and assembly costs. The largest cost in most structures today is assembly. As part of the NASA Advanced Composite Technology Program, Lockheed Aeronautical Systems Company has a contract to explore and develop advanced structural and manufacturing concepts using advanced composites for transport aircraft. Wing and fuselage concepts and related trade studies are discussed. These concepts are intended to lower cost and weight through the use of innovative material forms, processes, structural configurations and minimization of parts. The approach to the trade studies and the downselect to the primary wing and fuselage concepts is detailed. The expectations for the development of these concepts is reviewed.

Key issues in space nuclear power challenges for the future

Abstract: The future appears rich in missions that will extend the frontiers of knowledge, human presence in space, and opportunities for profitable commerce. Key to success of these ventures is the availability of plentiful, cost effective electric power and assured, low cost access to space. While forecasts of space power needs are problematic, an assessment of future needs based on terrestrial experience has been made. These needs fall into three broad categories: survival, self sufficiency and industrialization. The cost of delivering payloads to orbital locations from LEO to Mars has been determined and future launch cost reductions projected. From these factors, then, projections of the performance necessary for future solar and nuclear space power options has been made. These goals are largely dependent upon orbital location and energy storage needs. Finally the cost of present space power systems has been determined and projections made for future systems.

Energy requirements for the space frontier

Abstract: The cost of delivering payloads to Mars orbital locations from LEO is determined and future launch cost reductions are projected. The performance necessary for future solar and nuclear space power options is predicted, categorizing the needs as survival, self-sufficiency, and industralization. The cost of present space power systems is determined and projections are made for future systems.

Engineering issues in the design of a recirculating induction accelerator for heavy ion fusion

Abstract: Despite additional complexity, a recirculating induction accelerator system has potential for achieving significant cost reduction over linear induction accelerators. A study is being conducted to evaluate the feasibility and cost of a recirculating induction accelerator for heavy ions. This study has identified the major cost components of the recirculator system, evaluated the engineering feasibility of various accelerator sub-systems and estimated overall system efficiency. System studies have been conducted to evaluate the dependence of system costs and efficiency on various system parameters and configurations. This paper will present the results from some of the system studies along with an evaluation of the engineering feasibility issues for a specific system design. The discussion of engineering feasibility will include evaluation and analysis of technical feasibility as well as cost and efficiency of the accelerating pulse power systems and the beam bending systems. 6 refs., 7 figs., 1 tab.