joint pricing and ordering policy for two echelon imperfect production inventory model with two cycles abstract this study deals with an imperfect epq economic production quantity price dependent inventory model over two types of cycles in the first cycle the retailer sells only good product with actual price and in the second he sells the products with a discount price in the production run time the non conforming items are produced at a random rate and they are reworked after the regular production run time and the reworked items are almost perfect as good as original quality items the retailer starts the second cycle when a certain percent of good items are left to him after the completion of regular production the retailer continues simultaneously two cycles up to which both types of the products are available to him now our objective is to find out optimal ordering lot size and optimal price for which the profit of the integrated model is maximum also we check the best strategy of retailer for the time of starting second cycle a numerical example is provided to illustrate the behavior and application of the model

a deterministic inventory model for deteriorating items with stock dependent demand rate abstract a deterministic inventory model is developed by assuming that the demand rate is stock dependent and the items deteriorate at a constant rate the expression for the average net profit over one production run is derived and its optimization with respect to the decision variables q initial stock and t duration of a production cycle is carried out this leads to two highly nonlinear equations which are solved by using a subroutine neqnf in imsl math library in cyber 180 480a computer system the optimal solution so derived is compared with that for the no deterioration 0 case sensitivity of the optimal solution to changes in parameter values is examined several aspects of the functional form for the demand rate are considered in a separate section finally the salient features of the problem and its solution are discussed in brief

optimal production lot with imperfect production process under permissible delay in payments and complete backlogging abstract the traditional economic production quantity epq model assumes that the production products are all perfect it is not always true in the real production system due to imperfect production process or other factors imperfect quality items may be produced furthermore it is well known that the total production inventory costs can be reduced by reworking the imperfect quality items produced with a relatively smaller additional reworking and holding costs in addition the permissible delay in payments offered by the supplier is widely adopted in the practical business market in this study we explore the effects of the reworking imperfect quality items and trade credit on the epq model with imperfect production processes and complete backlogging a mathematical model which includes the reworking and shortage costs interest earned and interest charged is presented besides an arithmetic geometric mean inequality approach is employed and an algorithm is developed to find the optimal production policy furthermore some numerical examples and sensitivity analysis are provided to demonstrate the proposed model

an eoq model with stock dependent demand shortage inflation and time discounting abstract this paper develops a finite time horizon deterministic economic order quantity eoq inventory model with shortages where the demand rate at any instant depends on the on hand inventory stock level at that instant the effects of inflation and the time value of money are taken into account considering two separate inflation rates namely the internal company inflation rate and the external general economy inflation rate the results are discussed with a numerical example and particular case of the model is discussed in brief a sensitivity analysis of the optimal solution with respect to the parameters of the system is carried out

managing real time demand fluctuation under a supplier retailer coordinated system abstract we have considered a supplier retailer system that operates under an agreed coordinated policy with an imperfect production process and a possibility of having demand fluctuation in this paper a dynamic planning process is proposed to deal with short term demand fluctuations to do this a mathematical model was first developed for a single fluctuation either for increasing or decreasing demand rate the model generates a revised plan after the occurrence of the fluctuation event we also propose a new and efficient heuristic to solve the developed model secondly multiple fluctuations have been considered for which a new occurrence may or may not affect the revised plan of earlier occurrences and we extend the heuristic so that is capable of dealing with multiple demand fluctuations on a real time basis we have generated a good number of random test problems and also solved the model using a genetic algorithm in order to compare the solutions with our heuristic the comparison confirmed the consistent performance of our developed heuristic and also its lower computational time numerical examples and sensitivity analysis have been presented to explain the usefulness of the developed model

an econometric view on the estimation of gravity models and the calculation of trade potentials this paper presents an ar 1 model in the spirit of hausman and taylor zero differences between actual and in sample predicted trade flows large systematic differences between observed and in sample predicted trade flows only indicate model misspecification and econometric problems out of sample predictions make sense if countries of interest are in an early stage of the transformation process the gravity model remains an interesting tool for the calculation of counterfactuals e g the impact of catching up in gdp per capita in the ceec or of the reduction of trade costs via infrastructure investments or tariffs on bilateral trade etc for this line of research the difference between short term and long term influences could provide interesting insights

transaction cost economics the natural progression abstract this manuscript provides the nobel laureate s reflections on transaction cost economics the overview section frames governance as the overarching concept and transaction cost economics as the means by which to breathe operational content into governance and organization the vertical integration section identifies efficiency factors associated with determining when a firm produces a good or service to its own needs rather than outsource a discussion of the rudiments of transaction cost analysis is subsequently provided puzzles and challenges that require pushing the logic of efficient governance to completion are examined and followed by concluding remarks

inventory models with inventory level dependent demand a comprehensive review and unifying theory marketing researchers and practitioners have long recognized the demand of many retail items is proportional to the amount of inventory displayed recently two distinct types of inventory control models reflecting this relationship have appeared in the literature models in which the demand rate of an item is a function of the initial inventory level and those in which it is dependent on the instantaneous inventory level we present a comprehensive overview of this literature and demonstrate the equivalence of the two types of models through the use of a simple periodic review model an alternative approach to sensitivity analysis for inventory models with inventory level dependent demand is also presented

a production inventory model in an imperfect production process abstract the paper develops a model to determine the optimal product reliability and production rate that achieves the biggest total integrated profit for an imperfect manufacturing process the basic assumption of the classical economic manufacturing quantity emq model is that all manufacturing items are of perfect quality the assumption is not true in practice most of the production system produces perfect and imperfect quality items in some cases the imperfect quality non conforming items are reworked at a cost to restore its quality to the original one rework cost may be reduced by improvements in product reliability i e decreasing in product reliability parameter lower value of product reliability parameter results in increase development cost of production and also smaller quantity of nonconforming products the unit production cost is a function of product reliability parameter and production rate as a result higher development cost increases unit production cost the problem of optimal planning work and rework processes belongs to the broad field of production inventory model which deals with all kinds of reuse processes in supply chains these processes aim to recover defective product items in such a way that they meet the quality level of good item the benefits from imperfect quality items are regaining the material and value added on defective items and improving the environment protection in this point of view a model is introduced here to guide a firm industry in addressing variable product reliability factor variable unit production cost and dynamic production rate for time varying demand the paper provides an optimal control formulation of the problem and develops necessary and sufficient conditions for optimality of the dynamic variables in this purpose the euler lagrange method is used to obtain optimal solutions for product reliability parameter and dynamic production rate finally numerical examples are given to illustrate the proposed model

an inventory model for deteriorating items with stock dependent demand rate abstract this paper discusses an inventory model with an inventory level dependent demand rate followed by a constant demand rate for items deteriorating at a constant rate where the terminal condition of zero inventory at the end of the scheduling period has been relaxed sensitivity of the decision variables to changes in the parameter values is examined and the effects of these changes on the optimal policy are discussed in brief

revisiting the effects of regional trade agreements on trade flows with proper specification of the gravity model this paper uses a gravity model to assess ex post regional trade agreements the model includes 130 countries and is estimated with panel data over the period 1962 1996 the introduction of the correct number of dummy variables allows for identification of vinerian trade creation and trade diversion effects while the estimation method takes into account the unobservable characteristics of each pairs of trade partner countries the endogeneity of some of the explanatory variables as well as a potential selection bias in contrast to previous estimates results show that regional agreements have generated a significant increase in trade between members often at the expense of the rest of the world

trips trade and technology transfer a north south model of unintentional technology transfer is developed where the stringency of southern patent protection provides the institutional backdrop for a strategic game in a high tech goods market the appropriability regime is set endogenously and combines elements of imperfect southern patent protection with the protection afforded by market made northern technology masking less stringent protection of northern intellectual property can work much like other strategic trade policies therefore developed countries appear to be right in demanding discussion of intellectual property rights in gatt

tariffs and capacity utilization by monopolistically competitive firms abstract this paper examines the effect of a tariff imposed on a monopolistically competitive mc sector on firm output in a 2 2 2 model with nonhomothetic technology if the mc sector is capital intensive then a tariff will improve the terms of trade lower home firm demand elasticity but raise firm output relative to foreign firms if the mc sector is labor intensive then excess supply for firm output may be decreasing in price so the tariff may worsen the home country s terms of trade home firm demand elasticity falls but firm output rises relative to the partner country these results qualify conclusions based on single sector and single country models

is trade in electrical and electronic products sensitive to ipr protection evidence from china s exports abstractthis article attempts to provide the first empirical evidence on the effect of intellectual property rights iprs on china s export of electrical and electronic products it adopts a gravity model for unbalanced panel data of china s 146 important trading partners over the period of 2002 2012 to eliminate the effects of fdi in determining the linkage between ipr and exports the panel excludes the destination countries and territories that invest in china the results reveal that the level of ipr protection in destination countries has a positive impact on china s flow of exports further analysis on data disaggregated by ipr score demonstrates that a higher level of ipr protection in destination countries and territories is positively linked with china s exports of these items in each of the ipr protection clusters and indicates a strong market power effect by the interplay between r d expenditure and ipr in the destinations finally both market power and market expansion effects are found to

determinants of patent rights a cross national study abstract this paper presents an index of patent rights for 110 countries for the period 1960 1990 the index is used to examine what factors or characteristics of economies determine how strongly patent rights will be protected the evidence does indicate that more developed economies tend to provide stronger protection but the underlying factors which influence patent protection levels are the country s level of research and development r d activity market environment and international integration which are correlated with its level of development the results qualify however that r d activity influences patent protection levels after a nation s research sector reaches a critical size an implication of this is that to raise patent protection levels in weakly protecting countries it is important to foster a significant research base in those countries and thereby create incentives for protecting patent rights

optimal stopping and restarting production times for an eoq model with deteriorating items and time dependent partial backlogging abstract yan and cheng j operational res soc 49 1998 1288 1295 presented a general production inventory model with production rate product demand rate and deterioration rate all considered as functions of the time their model allows for shortages and partial backlogging of the unsatisfied demand at a constant rate in this paper we extend the results of yan and cheng to cover the case where the backlogging rate is a time dependent function and we propose an algorithm for the solution of this problem we also propose some conditions which we believe to be necessary for the validity for some of yan s and cheng s statements the paper closes with numerical examples which cover each one of the cases considered in the paper

foreign patent rights and high tech exports evidence from taiwan this paper conducts a consecutive pooled data analysis from 1989 to 2000 to investigate the relationship between foreign patent rights fprs and the exports of three high tech industries in taiwan the semiconductor the information and the communication equipment industries following smith s model setup empirical results indicate that both market expansion and market power effects do exist in taiwan s case in addition this paper proposes a new hypothesis in which the importing country may exhibit a stronger r d ability than the exporting country a case that has not been considered in earlier empirical work finally a test is made to determine if a trips trade related intellectual property rights agreement has any impact on the fprs exports relationship and no evidence is found of a structural change after the implementation of trips

an inventory model with both stock dependent demand rate and stock dependent holding cost rate abstract in this paper we develop an inventory model under a stock dependent demand rate and stock dependent holding cost rate with relaxed terminal conditions shortages are allowed and partially backlogged in the model the purpose of this study is to determine the optimal order quantity and the ending inventory level such that the total profit per unit time is maximized for the retailer we first establish a proper model for a mathematical formulation then we develop several theoretical results and provide the decision maker with an algorithm to determine the optimal solution finally numerical examples are provided to illustrate the solution procedure and a sensitivity analysis of the optimal solution with respect to major parameters is carried out

valuation of product mix flexibility using real options abstract flexibility in manufacturing operations is becoming increasingly more important to industrial firms due to e g increasing market demand volatility internationalisation of markets and competition and shorter product life cycles defining measuring and evaluating manufacturing flexibility have not been straightforward neither in theory nor in practice the use of real options has shown to be an accessible approach for the valuation of certain types of flexibility when using real options for capital budgeting purposes it is possible to take flexibility options into account in the valuation process in this paper we use real options to evaluate one specific type of manufacturing flexibility i e product mix flexibility we provide both theoretical and practical perspectives based on a real case the main interest of the company under study is to evaluate product mix flexibility with respect to capacity set ups level of automation and multi functionality of resources the case involves multiple products and demand uncertainty wherefore product demands are used as the underlying asset in the real options models thus the contribution of this paper concerns the combination of real case multiple products capacity constraints and set up costs the results of the analysis show that i the value of flexibility decreases when demand volatility increases ii flexible resources add substantial value as compared to dedicated resources and iii the flexibility value of marginal capacity decreases with increasing levels of capacity

intellectual property rights licensing and innovation in an endogenous product cycle model abstract we develop a dynamic general equilibrium model of the product cycle to study the effects of stronger intellectual property rights iprs in the south on the incentives of firms in the north to innovate and to license advanced technologies innovation and licensing are random processes requiring resources stronger iprs increase the licensor s share of rents and reduce the costs of licensing contracts thus the returns to both licensing and innovation would rise while additional resources would be available for r d in consequence innovation and technology transfer would rise however the effect of stronger iprs on relative wages between regions is ambiguous

the antitrust implications of capacity reallocation by a dominant firm when a firm acquires rival firms in one market and moves their capacity to another market should antitrust authorities be concerned we address this question by studying a multi stage game a dominant firm has the opportunity to acquire fringe firms that operate in the same market then the dominant firm has the opportunity to move capacity from that market to a second market the model is motivated by a series of acquisitions in the specialized mobile radio industry aimed at establishing a new cellular carrier we derive necessary and sufficient conditions for the dominant firm to acquire too little capacity relative to the social optimum the results shed light on the consent decree negotiated in us v motorola inc and nextel communications inc 1994

monopoly and the preemption of competitive recycling the paper shows that a monopolistic primary producer of a recycleable material will choose to preempt market entry by competitive recyclers unless the cost of producing virgin ingot is very high compared to the cost of reconditioning used material unlike earlier results it is shown that in the absence of transaction costs on scrap sales competition by independent recyclers fails to reduce price below its full monopoly level moreover if transaction costs are present the mere threat of entry by independent recyclers may raise the price above that level

sleeping quotas pre emptive quota bidding and monopoly power abstract we rationalize the puzzling existence of binding quotas that are not fully utilized our model has its roots in bhagwati 1965 in r baldwin et al eds trade growth and the balance of payments essays in honor of g haberler mit press new york on tariffs quotas equivalence and is related to the io literature on preemption we study the conditions that lead a monopolist facing a quota restricted market to buy the quota licenses itself and the conditions under which they may remain unused the divisibility of the quota is crucial for the monopolist to pre emptively buy the quota furthermore we study the implications of use it orlose it clauses commonly imposed on auctioned quotas

piecewise procurement of a large scale project this paper studies the optimal piecewise procurement of a large scale project in the unique markov perfect equilibrium mpe of the dynamic procurement game it is found that 1 unlike the static setting the procurer s optimal strategy depends on the number of suppliers and more importantly it is nonmonotonic as one more supplier participates in the procurement auction the procurer softens competition in the initial stages by including more cost btypesq while increasing competition in the mature stages 2 this in turn implies that existing suppliers might favor participation of additional suppliers 3 absent scheduling and or resource constraints the procurer prefers to procure the project as one piece if the suppliers technology exhibits constant or increasing returns and no additional suppliers are enticed to bid and 4 the optimal dynamic mechanism can be easily implemented via a sequence of dominant strategy auctions of the vickrey type d 2004 elsevier b v all rights reserved

do national patent laws stimulate domestic innovation in a global patenting environment a cross country analysis of pharmaceutical patent protection 1978 2002 this paper evaluates the effects of patent protection on phar maceutical innovations for 26 countries that established pharmaceutical patent laws during 1978 2002 controlling for country characteristics through matched sampling techniques to establish two proper comparison sets among 92 sampled countries and through country pair fixed effects regressions this study yields robust results national patent protection alone does not stimulate domestic innovation as estimated by changes in citation weighted u s patent awards domestic r d and pharmaceutical industry exports however domestic innovation accelerates in countries with higher levels of economic development educational attainment and economic freedom additionally there appears to be an optimal level of intellectual property rights regulation above which further enhancement reduces innovative activities

managing dynamic competition in many important high technology markets including software development data processing communications aeronautics and defense suppliers learn through experience how to provide better service at lower cost this paper examines how a buyer designs dynamic competition among rival suppliers to exploit learning economies while minimizing the costs of becoming locked in to one producer strategies for controlling dynamic competition include the handicapping of more efficient suppliers in procurement competitions the protection and allocation of intellectual property and the sharing of information among rival suppliers jel c73 d44 l10

strategic entry deterrence in analyzing deterrence of large scale entry two classes of entry barriers may be distinguished an innocent entry barrier is unintentionally erected as a side effect of innocent profit maximization in contrast a strategic entry barrier is purposely erected to reduce the possibility of entry two types of innocent barriers may also be distinguished a postentry absolute advantage has the property that if entry did occur the established firm would be at a profit advantage over the entrant examples are superior technology or product design patents and lower input prices a preentry asymmetry advantage arises from the fundamental preentry asymmetry between established firm and potential entrant before the entrant makes his entry decision the established firm has already committed resources this prior existence gives first move advantages the preentry asymmetry is independent of symmetry or asymmetry in the rules the equilibrium concept of the postentry game that might ensue even if the postentry game will be played according to nash cournot or entrant as leader rules the preentry leadership

trips trade and growth a two country model of endogenous growth is employed to assess the importance of intellectual property rights to trade growth and technology transfer the paper provides theoretical results linking the intellectual property rights regime to trade patterns aggregate r d worldwide growth and aggregate welfare measures failure to provide patent protection for foreign made innovations forces innovators to employ less than the best practice research technologies reduces aggregate r d activities worldwide effectively eliminates technology transfer across countries and reduces worldwide growth copyright 1994 by economics department of the university of pennsylvania and the osaka university institute of social and economic research association

does aid cause trade evidence from an asymmetric gravity model anderson and vanwincoop developed what has become the standard framework for framing and interpreting empirical work using the gravity model their framework relies heavily on an assumption of symmetry among countries for issues related to north south trade this assumption is problematic in this paper we develop an asymmetric extension of the anderson vanwincoop framework appropriate to the analysis of north south trade where northern countries produce differentiated goods and southern countries homogenous ones in addition we use an appropriately extended version of baier and bergtrand and taylor linear expansion thus permitting its estimation using good old ols the result is an empirical model that i is better suited to the analysis of north south trade ii is easy to estimate and compute comparative statics not requiring a customised nls routine and given the way the south is included iii provides a simple explanation of zero trade flows between some country pairs a fact still not fully explained in the literature as an illustration of its use we examine the empirical link between foreign aid and trade

production inventory models for a damageable item with variable demands and inventory costs in an imperfect production process in this paper economic production quantity epq models for breakable or deteriorating item are developed with variable demands being dependent on time or on hand stock here rate of production and holding cost are time dependent unit production cost is a function of both production reliability indicator and production rate set up cost is also partially production rate dependent the production process produces some imperfect quantities which are instantly reworked at a cost to bring back those units to the perfect ones the production process ultimately depends on both time and reliability indicator the models are formulated as optimal control problems and the total profit functions with effect of inflation and time value of money are expressed as finite integrals over the finite planning horizon the problems are solved using euler lagrange function based on variational calculus and newton raphson method to determine the optimal production reliability indicator r and then corresponding production rates and total profits in some cases results of the models for deteriorating item are obtained as particular cases from those of breakable item models similarly results of simple epq models without damageability are deduced as particular cases numerical experiments are performed to illustrate the models both numerically and graphically

a generalized design for bilateral trade flow models abstract this paper suggests a full interaction effects design to analyze bilateral trade flows this is illustrated with an unbalanced panel of bilateral trade between the triad eu15 usa and japan economies and their 57 most important trading partners over the period 1986 1997 our full interaction model finds empirical support for the new trade theory and linder s hypothesis we show that the omission of one or more interaction effects can result in biased estimates and misleading inference

are weak patent rights a barrier to u s exports abstract this paper assesses whether how and to what extent u s exports are sensitive to national differences in patent rights i estimate bilateral trade equations that account for trade distortions related to patent rights using data on state to country manufacturing exports in 1992 i find that weak patent rights are a barrier to u s exports but only to countries that pose a strong threat of imitation e g china the stronger patent rights required under the wto agreement increase u s exports to these high threat markets alternatively strengthening patent rights in countries that pose a weak threat of imitation reinforces monopoly power and reduces u s exports to these markets

an optimal replenishment policy for non instantaneous deteriorating items with stock dependent demand and partial backlogging abstract in this study we consider a problem of determining the optimal replenishment policy for non instantaneous deteriorating items with stock dependent demand in the model shortages are allowed and the backlogging rate is variable and dependent on the waiting time for the next replenishment the necessary and sufficient conditions of the existence and uniqueness of the optimal solution are shown as the special cases the results for the models with instantaneous or non instantaneous deterioration rate and with or without shortages are derived further we analytically identify the best circumstance among these special cases based on the minimum total relevant cost per unit time sensitivity analysis of the optimal solution with respect to major parameters is carried out finally four numerical examples are presented to demonstrate the developed model and the solution procedure

an imperfect production process in a volume flexible inventory model abstract this paper hypothesizes an imperfect production inventory system where the items produced are a mixture of perfect and imperfect quality some of the imperfect quality items can be sold at a reduced selling price the unit production cost is taken to be a function of the finite production rate which is treated as a decision variable the mathematical expression for the expected profit function is derived and it is maximized subject to different constraints of the system using interior penalty function method for constrained optimization the algorithm of which is given the solution procedure is illustrated with the help of numerical examples the sensitivity of each variable to changes in the values of the parameters of the system is examined lastly various issues conforming the system are discussed

preemptive patenting and the persistence of monopoly this article takes a different tack and inquires whether institutions such as the patent system create opportunities for firms with monopoly power to maintain their monopoly power the results apply to other situations such as brand identification spatial location and capacity expansion which share the characteristic that early or preemptive actions may lower the returns to potential competitors

inventory models with the demand rate dependent on stock and shortage levels this paper investigates an inventory system in which the demand rate during stockout periods differs from that during the in stock period by a given amount the previous analysis conducted in this area formulated the model as a cost minimization model this type of formulation will intentionally try to decrease demand by increasing the stockout period in order to decrease costs this paper appropriately considers the model as a profit maximization model and develops a closed form solution the model is then further generalized to incorporate the effect of stock level dependent demand rates and considers initial stock dependent demand as well as instantaneous stock dependent demand rates

effects of inflation and time value of money on an inventory model with linear time dependent demand rate and shortages abstract in the present paper an attempt has been made to investigate the effects of inflation and time value of money on an inventory model with linear time dependent demand rate shortages are allowed in this model the model developed in this article is a finite horizon t si policy inventory model to the best of the authors knowledge such type of inventory model has not been considered earlier a numerical example has also been given to illustrate the developed model

how trade related are intellectual property rights abstract there is little empirical evidence about whether differing international levels of patent protection influence trade flows if a nation strengthens its patent laws it could experience higher or lower imports we specify an empirical model in which deviations of bilateral sectoral imports from anticipated levels are related to income trade barriers and patent laws patent regulations in the importing country are corrected for endogeneity through the use of instrumental variables the results of the final equations indicate that increasing patent protection has a positive impact on bilateral manufacturing imports into both small and large developing economies

demand promotion by upgradation under stock dependent demand situation a model the idea of demand promotion by upgrading the existing system of the selling centre has been modelled in this article the consumption rate is assumed to be dependent on the stock level the problem has been reduced to a maximizing problem the algorithmic approach for solving this maximizing problem is also provided objective is to maximize the net profit over a prescribed time an increasing convex upgradation cost is considered exponential upgradation cost has been considered for the numerical examples

the impact of patent rights on international trade evidence from canada the extent to which canadian manufacturing exports are sensitive to national differences in patent rights are examined the conclusion is that overall canadians tend to export more to those countries where their patent rights are highly safeguarded stronger patent protection induces canadians to export relatively more to high income countries than to low income countries in addition the effect of stronger patent rights is to increase exports to those countries that pose a strong threat of imitation and to reduce exports to those countries that pose the weakest threat of imitation jel classification f13 o34 impact de la propriete des brevets sur le commerce international resultats pour le canada ce memoire examine jusqu a quel point les exportations manufacturieres canadiennes sont sensibles aux differences dans la propriete des brevets entre pays l etude conclut que les canadiens tendent a exporter davantage vers les pays ou la propriete des brevets est hautement protegee il appert que la plus forte protection de la propriete des brevets tend a faire que les canadiens exportent relativement plus vers les pays a hauts revenus que vers ceux a plus faibles revenus de plus il appert que l effet de la plus forte protection des brevets est d accroitre les exportations vers les pays qui posent une forte menace d imitation et de reduire les exportations vers les pays qui posent la plus faible menace d imitation

a two echelon inventory distribution system with power demand pattern and backorders abstract this paper addresses the implications of considering power demand pattern and backorders in the one warehouse n retailer problem specifically we assume that items at the retailers are withdrawn from the inventory following a power pattern the objective function consists of the sum of ordering holding and backordering costs at all installations this objective function depends on the class of inventory policies that we choose for the formulation of the problem in general obtaining the cost function is an arduous task since the average inventory at the warehouse could be difficult to determine however if we apply single cycle policies the computation of the total average cost becomes possible under these assumptions we show that the one warehouse n retailer system with power demand pattern and backorders can be formulated as a mixed non linear programming problem

an optimal procurement policy for items with an inventory level dependent demand rate and fixed lifetime abstract this paper investigates an optimal procurement policy for items with an inventory level dependent demand rate and fixed lifetime the demand rate is assumed to be a function of current inventory level and each unit has its fixed expiry date so any units which remain unused by their expiry date are considered outdated and must be disposed of for the system presented a mathematical model and solution methodology were developed sensitivity of the decision variables to changes in the parameter values is examined and future research needs are discussed in brief

optimal and heuristic inventory replenishment models for deteriorating items with exponential time varying demand abstract in this paper we present optimal and heuristic procedures for the inventory replenishment problem in which items are deteriorating at a constant rate the demand rates are changing exponentially with time over a known and finite planning horizon we have developed an iterative numerical procedure to find the optimal replenishment schedule the first two heuristics are based on the economic order interval approximation the third heuristic restricts all the replenishment cycles over the planning horizon to be equal over the planning horizon the last three heuristics are extended versions of the silver meal heuristic the least cost approach and the least unit cost heuristic which were used in the inventory literature for the case of discrete time varying demand without deterioration we further assess the cost and computation time effectiveness of the six heuristics the results of a sample of 1440 problems show that the extended least cost approach is the most cost effective

heuristics for impulse replenishment with continuous periodic demand abstract we present a model where the demand appears at continuous time and all demand must be met the demand function is periodic with active and passive periods linear increasing and decreasing demand rates respectively the inventory is replenished at discrete time this paper is concerned with the problem of how to determine the replenishment schedule that minimizes the total production and holding cost over a long time horizon we show that there is no forecast horizon in our model even if the demand rate is constant there exists approximate forecast horizon for such case we obtain an explicit formula for the minimal sets of rational initial decisions for the periodic demand rate case we formulate some necessary conditions for optimal schedules two heuristics are also proposed the first is an improved version of the silver meal heuristic and the second is based on turnpike policies

how do foreign patent rights affect u s exports affiliate sales and licenses abstract this paper analyzes how foreign patent rights fprs affect us exports affiliate sales and licenses our approach is distinctive in three ways we apply ownership location and internalization concepts to link fprs with servicing decisions we account for the simultaneity of servicing decisions we estimate the relative effects of fprs on exports affiliate sales and licenses empirical findings show strong fprs increase us affiliate sales and licenses particularly across countries with strong imitative abilities further fprs have a larger effect on us knowledge transferred outside the country and firm relative to knowledge located inside the country and internalized inside the firm

optimal production inventory policy for an integrated multi stage supply chain with time varying demand abstract an integrated multi stage supply chain with time varying demand over a finite planning horizon is considered in this paper the objective is to devise the optimal production inventory policy to minimize the total operational cost the model is formulated as a mixed integer nonlinear programming problem the problem is represented as a weighted directed acyclic graph the global minimum total operational cost is computed in polynomial time by the developed algorithm two numerical examples of a seasonal product and a product over its life cycle are studied to illustrate the results a sensitivity analysis of the system parameters is conducted to assist the supply chain decision makers

a production inventory model for a deteriorating item with trended demand and shortages abstract a production inventory model is developed for a deteriorating item over a finite planning horizon with a linear time varying demand finite production rate and shortages the resulting nonlinear constrained minimization problem is numerically solved by using the box complex algorithm the optimal number of production cycles that minimizes the average system cost is determined sensitivity analysis of the optimal solution is carried out

has distance died evidence from a panel gravity model the estimated coefficient of distance on the volume of trade is generally found to increase rather than decrease through time using the traditional gravity model of trade this distance puzzle proved robust to several ad hoc versions of the model using data for 1962 96 for a large sample of 130 countries the introduction of an augmented barrier to trade function removes the paradox yielding a decline in the estimate of the elasticity of trade to distance of about 11 percent over the 35 year period for the whole sample however the death of distance is shown to be largely confined to bilateral trade between rich countries with poor countries becoming marginalized

the economics of governance the economics of governance is an effort to implement the study of good order and workable arrangements where good order includes both spontaneous order in the market which is a venerated tradition in economics adam smith 1776 friedrich hayek 1945 kenneth a arrow and gerard debreu 1954 and intentional order of a conscious deliberate purposeful kind chester irving barnard 1938 p 9 also i interpret workable arrangements to mean feasible modes of organization all of which are flawed in comparison with a hypothetical ideal avinash dixit 1996 pp 4 9 the object is to work out the efficiency logic for managing transactions by alternative modes of governance principally spot markets various long term contracts hybrids and hierarchies interest among social scientists economists included in the study and practice of good order and workable arrangements has been steadily growing in contrast with the orthodox lens of choice prices and output supply and demand the economics of governance is a lens of contract construction broadly in the spirit of james buchanan s 2001 p 29 observation that mutuality of advantage from voluntary exchange is the most fundamental of all understandings in economics the economics of governance as herein described is principally an exercise in bilateral private ordering by which i mean that the immediate parties to an exchange are actively involved in the provision of good order and workable arrangements to be sure the need for private ordering varies with the rules of the game as provided by the state distinctions between lawlessness where the state provides limited or unreliable protection for property and contract dixit 2004 and lawfulness where the state undertakes to protect property and enforce contracts in a principled way are pertinent the first of these applies mainly to primitive and transition economies the second is commonly associated with western democracies recourse to private ordering under conditions of lawlessness is altogether understandable given the absence of state support the walter a haas school of business university of california berkeley ca 94720 1900 the paper has benefited from workshop presentations at the university of california berkeley the university of valencia insead fountainebleau and the 2004 annual conference of the international society for new institutional economics an abbreviated version was also given as the horst claus recktenwald lecture at nuremburg on 4 november 2004 comments and suggestions from fred balderston ernesto dalbo avinash dixit robert gibbons witold henisz ian larkin steven tadelis and dean williamson are especially acknowledged 1 lon fuller s 1954 p 477 definition of eunomics as the science theory or study of good order and workable arrangements is very much in the spirit of what i refer to as governance 2 one of the immediate ramifications of insistently comparing feasible alternatives all of which are flawed is that the purported inefficiencies that are ascribed to failures to achieve first best optimality are not dispositive but invite the query as compared with what i return to this issue in section iv 3 excluding corporate governance the numbers of articles that used the word governance during the period 1998 2000 as compared with the period 1977 1979 in selected economics business management sociology organization and political science journals were 60 vs 1 76 vs 4 79 vs 18 and 60 vs 25 where the journals surveyed were the american economic review journal of political economy quarterly journal of economics rand journal of economics and journal of economic perspectives in economics strategic management journal management science academy of management journal and academy of management review in business management administrative science quarterly organization science american journal of sociology american sociological review and annual review of sociology in sociology organization and american political science review political science quarterly journal of politics and political research quarterly in political science combining these four categories articles using the word governance increased from 48 to 275 over this 20 year interval dixit 2004 pp 149 50 reports that the number of web pages that turn up under the search for governance is huge

effects of inflation and the time value of money on order quantity and allowable shortage abstract this paper investigates the effects of inflation and time value of money on the optimal ordering quantities and the maximum allowable shortage in a finite replenishment inventory system the present value of total cost incurred in this inventory system is developed first then an optimal order quantity and maximum allowable shortage are obtained by using a search procedure the effect of inflation and time value of money was investigated under given sets of values of inflation and discount rates this study shows that the optimal order quantity and maximum allowable shortage vary with the change in difference between inflation and time discount computational results indicate that this effect on the system becomes more significant with the increase of the difference between inflation rate and time discount rate