77 research outputs found

    LINE SEARCH TECHNIQUES FOR THE LOGARITHMIC BARRIER FUNCTION IN QUADRATIC-PROGRAMMING

    Get PDF
    In this paper, we propose a line-search procedure for the logarithmic barrier function in the context of an interior point algorithm for convex quadratic programming. Preliminary testing shows that the proposed procedure is superior to some other linesearch methods developed specifically for the logarithmic barrier function in the literature

    Integrated Production Maintenance And Quality Model For Imperfect Processes

    Get PDF
    In this paper, we develop an integrated model for the joint optimization of the economic production quantity, the economic design of (x) over bar-control chart, and the optimal maintenance level. This is done for a deteriorating process where the incontrol period follows a general probability distribution with increasing hazard rate. In the proposed model, Preventive Maintenance (PM) activities reduce the shift rate to the out-of-control state proportional to the PM level. Compared to the case with no PM, the extra cost of maintenance results in lower quality control cost which may lead to lower overall expected cost. These issues are illustrated using an example of a Weibull shock model with an increasing hazard rate

    LINE SEARCH TECHNIQUES FOR THE LOGARITHMIC BARRIER FUNCTION IN QUADRATIC-PROGRAMMING

    Get PDF
    In this paper, we propose a line-search procedure for the logarithmic barrier function in the context of an interior point algorithm for convex quadratic programming. Preliminary testing shows that the proposed procedure is superior to some other linesearch methods developed specifically for the logarithmic barrier function in the literature

    Integrated Production And Quality Model Under Various Preventive Maintenance Policies

    Get PDF
    In this paper, we investigate the effect of various preventive maintenance policies on the joint optimisation of the economic production quantity (EPQ) and the economic design of control chart. This has been done for a deteriorating process where the incontrol period follows a general probability distribution with increasing hazard rate. In the proposed model, preventive maintenance (PM) activities reduce the shift rate of the system to the out-of-control state proportional to the PM level. For each policy, the model determines the EPQ, the optimal design of the control chart and the optimal preventive maintenance level. The effects of the three PM policies on EPQ and quality costs are illustrated using an example of a Weibull shock model with an increasing hazard rate

    Effect Of Inspection Errors And Preventive Maintenance On A Two-Stage Production Inventory System

    Get PDF
    The effect of imperfect production processes on lot-sizing decisions has received a lot of attention in the literature. These efforts have mostly been confined to single-stage production systems. The issue of imperfect production processes has not been adequately addressed in the context of multistage production/inventory systems. In this paper, we propose a production inventory model that takes into account the effect of imperfect production processes, preventive maintenance and inspection errors. Numerical examples are presented for illustrative purposes

    Lead-Time Reduction In A Stochastic Inventory System With Learning Consideration

    Get PDF
    We develop a continuous review inventory model where lead-time is considered as a controllable variable. Lead-time is decomposed into all its components: set-up time, processing time and non-productive time. These components reflect the setup cost reduction, lot size lead-time interaction and lead-time crashing, respectively. The learning effect in the production process is also included in the processing time component of the lead-time. The finite investment approach for lead-time and set-up cost reduction and their joint optimization, in addition to the lot size lead-time interaction, introduce a realistic direction in lead-time management and control. A numerical example and a sensitivity analysis are presented using the design of experiments to investigate the effect of the model parameters and, in particular, those related to the different lead-time components on the the expected total cost
    corecore