An Inventory Model for Deteriorating Commodity under Stock Dependent Selling Rate

Economic order quantity (EOQ) is one of the most important inventory policy that have to be decided in managing an inventory system. The problem addressed in this paper concerns with the decision of the optimal replenishment time for ordering an EOQ to a supplier. This Model is captured the affect of stock dependent selling rate and varying price. We developed an inventory model under varying of demand-deterioration-price of commodity when the relationship of supplier-grocery-consumer at stochastic environment. The replenishment assumed instantaneous with zero lead time. The commodity will decay of quality according to the original condition with randomize characteristics. First, the model is addressed to solve a problem phenomenon how long is the optimum length of cycle time. Then, an EOQ of commodity to be ordered by will be determined by model. To solve this problem, the first step is developed a mathematical model based on reference’s model, and then solve the model analytically. Finally, an inventory model for deteriorating commodity under stock dependent selling rate and considering selling price was derived by this research. Keywords: deterioration commodity, expected profit, optimal replenishment time stock dependent selling rate

Towards a more appropriate method for determining the optimal scale of production units

In this paper the overall diseconomies experienced beyond certain production unit scale thresholds are investigated. These are due to several costs, including those relating to the consumption of non- renewable resources, which firms have generally not internalised, to the extent that they can operate far beyond the socially optimal scale. Economic instruments such as environmental taxes may induce a shift towards marginally more sustainable production levels for a plant of a given size, but they are not designed to affect the plant size itself. This paper suggests a method for determining a socially optimal scale, by focussing on the factors which determine optimality. The results of applying this method show that establishing the scale of production units at a social optimum rather than a private one implies a significant decrease in scale for most economic activities. Downscaling has significant economic welfare and environmental advantages. Incentives linked to the factors which determine the social optimum are put forward as measures for inducing a shift towards an optimal size for production units.optimal scale, sustainable production, market areas

An Examination of the Implications of Milk Quota Reform on the Viability and Productivity of Dairy Farming in Ireland

End of project reportThe aim of the project was to produce quality, scientific based policy advice on the most efficient means for the transfer of milk quota between dairy farmers. The main objective of the project was to identify milk quota transfer mechanisms that would ensure the viability of the maximum number of farmers in Ireland while still supporting an internationally competitive agricultural sector. During the course of the project the Irish Department of Agriculture introduced a new milk quota transfer scheme. The milk quota exchange scheme was launched in November 2006. At this stage the objectives of the project were altered to be more policy relevant. Rather than exploring the efficiency of various milk quota transfer models, the aim of the project was redirected to explore the efficiency of the scheme as it was operated in Ireland. The rationale for this change was to provide relevant and timely feedback to policy makers on the operation of the new scheme. While the MTR agreement guaranteed the continuation of the EU milk quota regime until 2014/15, it also made provisions for a review of the milk quota system to be conducted in 2008. Clearly any changes to EU milk quota policy would have implications for farmers in Ireland. A second objective of this project was to explore some policy scenarios that may transpire from the milk quota review and to estimate the implications for farmers in Ireland

Buyback and return policies for a book publishing firm = Egy könyvkiadó vállalat visszavásárlási stratégiája

A dolgozat célja egy vállalati gyakorlatból származó eset elemzése. Egy könyvkiadót tekintünk. A kiadó kapcsolatban van kis- és nagykereskedőkkel, valamint a fogyasztók egy csoportjával is vannak kapcsolatai. A könyvkiadók projekt rendszerben működnek. A kiadó azzal a problémával szembesül, hogy hogyan ossza el egy frissen kiadott és nyomtatott könyv példányszámait a kis- és nagykereskedők között, valamint mekkora példányszámot tároljon maga a fogyasztók közvetlen kielégítésére. A kiadóról feltételezzük, hogy visszavásárlási szerződése van a kereskedőkkel. A könyv iránti kereslet nem ismert, de becsülhető. A kis- és nagykereskedők maximalizálják a nyereségüket. = The aim of the paper is to analyze a practical real world problem. A publishing house is given. The publishing firm has contacts to a number of wholesaler / retailer enterprises and direct contact to customers to satisfy the market demand. The book publishers work in a project industry. The publisher faces with the problem how to allocate the stocks of a given, newly published book to the wholesaler and retailer, and to hold some copies to satisfy the customers direct from the publisher. The publisher has a buyback option. The distribution of the demand is unknown, but it can be estimated. The wholesaler / retailer maximize the profits. The problem can be modeled as a one-warehouse and N-retailer supply chain with not identical demand distribution. The model can be transformed in a game theory problem. It is assumed that the demand distribution follows a Poisson distribution

How do markets manage water resources?. An experiment on resource market (de) centralization with endogenous quality.

We test how a monopoly, a duopoly and a public monopoly manage and allocate water resources. Stock depletion for the public monopoly is fastest. However, it reaches the optimal stock level towards the end of the experimental sessions. The private monopoly and duopoly maintain inefficiently high levels of stock throughout the sessions. The average quality to price ratio offered by the public monopoly is substantially higher than that offered by the private monopoly or duopoly. A clear result from the experiments is that a public monopoly offers the highest (average) quality to price ratio and has the fastest rate of stock depletion compared to a private monopoly or duopoly

Decision support for build-to-order supply chain management through multiobjective optimization

This paper aims to identify the gaps in decision-making support based on multiobjective optimization for build-to-order supply chain management (BTOSCM). To this end, it reviews the literature available on modelling build-to-order supply chains (BTO-SC) with the focus on adopting multiobjective optimization (MOO) techniques as a decision support tool. The literature has been classified based on the nature of the decisions in different part of the supply chain, and the key decision areas across a typical BTO-SC are discussed in detail. Available software packages suitable for supporting decision making in BTO supply chains are also identified and their related solutions are outlined. The gap between the modelling and optimization techniques developed in the literature and the decision support needed in practice are highlighted and future research directions to better exploit the decision support capabilities of MOO are proposed

Decision-Making and the Newsvendor Problem – An Experimental Study

This paper investigates repetitive purchase decisions of perishable items in the face of uncertain demand (the newsvendor problem). The experimental design includes: high, or low profit levels; and uniform, or normal demand distributions. The results show that in all cases both learning and convergence occur and are effected by: (1) the mean demand; (2) the order-size of the maximal expected profit; and (3) the demand level of the immediately preceding round. In all cases of the experimental design, the purchase order converges to a value between the mean demand and the quantity for maximizing the expected profit.Inventory, Learning, Behavior, Management, Optimization

Decision support for build-to-order supply chain management through multiobjective optimization

This is the post-print version of the final paper published in International Journal of Production Economics. The published article is available from the link below. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. Copyright @ 2010 Elsevier B.V.This paper aims to identify the gaps in decision-making support based on multiobjective optimization (MOO) for build-to-order supply chain management (BTO-SCM). To this end, it reviews the literature available on modelling build-to-order supply chains (BTO-SC) with the focus on adopting MOO techniques as a decision support tool. The literature has been classified based on the nature of the decisions in different part of the supply chain, and the key decision areas across a typical BTO-SC are discussed in detail. Available software packages suitable for supporting decision making in BTO supply chains are also identified and their related solutions are outlined. The gap between the modelling and optimization techniques developed in the literature and the decision support needed in practice are highlighted. Future research directions to better exploit the decision support capabilities of MOO are proposed. These include: reformulation of the extant optimization models with a MOO perspective, development of decision supports for interfaces not involving manufacturers, development of scenarios around service-based objectives, development of efficient solution tools, considering the interests of each supply chain party as a separate objective to account for fair treatment of their requirements, and applying the existing methodologies on real-life data sets.Brunel Research Initiative and Enterprise Fund (BRIEF

Scope of Innovations, Knowledge Spillovers and Growth

This paper exploits the formalization of a circular product differentiation model of Salop (1979) to propose an endogenous growth quality ladder model in which the knowledge inherent in a given sector can spread variously across the sectors of the economy, ranging from local to global influence. Accordingly, this affects the size of the pool of knowledge in which innovations draw themselves on in order to be produced. Therefore, the law of knowledge accumulation, and thus the growth rate of the economy, depend positively on the expected scope of diffusion of innovations, i.e. on the intensity of knowledge spillovers. This approach generalizes the endogenous growth theory as developed in the seminal models of Grossman & Helpman (1991) and Aghion & Howitt (1992), extending their analysis to the possibility of considering stochastic and partial knowledge spillovers. This framework allows us to mitigate the positive externality of knowledge and thus to apprehend the issue of the funding of research with more parsimony. We characterize the set of steady-state Schumpeterian equilibria as a function of the public tools. We provide an explanation for the fact that research effort can either be suboptimal or over-optimal, depending on the expected scope of knowledge. Accordingly, we find that the optimal public tool dedicated to foster R&D activity depends positively on it.Schumpeterian growth, scope of diffusion of innovations, knowledge spillovers