The future has always caught the attention of the human being. The thirst of exploring the future and to know the unknown has driven the human being toward innovativeness. Companies are expanding their operations worldwide since the past few decades. Profit growth coupled with an effective strategy has become the primary need of global companies. Research in this area has given rise to optimization of the supply chain for higher profitability. Considering the overall strategy the company needs to plan production well in advance. The operational planning comes in picture at this moment. In order to reduce excessive inventory at each stage of the production; one should know the demand of the next stage and preferably the end customer demand. The process of sales forecasting is undertaken to predict demand at different stages. It is a complex managerial function and hence needed to be undertaken by a scientific way. The sales forecasting the function includes process of forecasting, administration, hardware, software, users and developers of forecast. Historically sales forecasting has been considered as a side activity by most of the companies. Sales forecasting has not been considered as an important function of marketing and finance. Very few companies have seen sales forecasting by a scientific management point of view. Less research has been reported in sales forecasting in comparison to other managerial functions. Planning based on sales forecasting; may be part of a selected strategy for growth and profitability. These facts have attracted us to study sales forecasting as a managerial function. The purpose of this study is to describe and analyze the sales forecasting process, sales forecasting system, sales forecasting methods and techniques. Further proposing possibilities of improvements in existing forecasting process is also purpose of this study. We have selected three manufacturing companies for this study based on purposive sampling. Considering research interest in phenomenon study; we have selected a qualitative research strategy for this study. We have selected a case study method for our research as it is the most appropriate tool to study the relation between theory and phenomenon. For this research, we have collected the data by semistructured interviews based on a pre formed questionnaire. The questionnaire has been prepared with respect to our research purpose and open ended questions were used to gather extensive data. The data gathered during interviews, have been analyzed by the use of ‘Flow model’ suggested by Miles and Huberman (1994). Results from this study shows that there is a need to see ‘sales forecasting’ as a management function rather than a computer activity. To achieve the best information integration throughout the supply chain, increased information visibility is needed. To achieve accuracy in both forecasting and planning; collaborative forecasting may be used. Forecasting software needs to have a suite of methods towards product specific forecasting. The need of customized softwares has also been indicated by this study. The need to measure performance of forecasting by means of accuracy, cost and customer relationship has been concluded.

I denna undersökning studeras ett reservdelsflöde inom eftermarknad ur ett organisatorisktperspektiv. Reservdelen glidskenan på Atlas Copcos borriggar fungerar som fallstudieobjekt. Glidskenan är en tunn stålprofil, som mäter mellan två och åtta meter och skyddar matarbalkarna på ovan- och underjordsborriggar mot slitage. Vår uppdragsgivare Atlas Copcos Shared Distributionscenter (i fortsättningen DC) upplever problem i flödet av glidskenor. Glidskenan är skrymmande och svår att hantera, förpacka och transportera och flödet flyter inte effektivt. De upplevda problemen har varit kända i över 12 år och förbättringsansatser har runnit ut i sanden. Genom kartläggning av hur flödet flyter idag och hur organisationen runt flödet agerar har tre teman presenterats och analyserats. Dessa tre teman förklarar de bakomliggande organisatoriska aspekterna som påverkar glidskenans flöde och varför de upplevda problemen inte blir åtgärdade. Studien lyfter fram vikten av samarbete mellan de olika organisatoriska funktionerna och individerna i organisationen. Om samarbetet dem emellan fungerar kan synergieffekter erhållas, men ett bristande samarbete kan också hämma organisationens potential. Det första temat behandlar att kunskap finns inom organisationen, men att den inte sprids mellan medarbetarna. Med utgångspunkt i studiens andra tema konstaterar vi att medarbetarnas olika syn på glidskenan utgör en barriär för kunskapsspridning. Olika syn hämmar även medarbetarnas engagemang och intresse för att hitta förbättringar inom glidskenans flöde. I studiens tredje tema, avstånd, ser vi att organisationens fysiska men framförallt mentala avstånd hindrar organisationsmedlemmarna att känna en vi-samhet. Utan denna vi-samhet finns inga incitament till samarbete för att effektivisera glidskenans flöde. / In this research a spare part flow within aftermarket has been studied through an organizational perspective. The slide-bar is a spare part in Atlas Copco Rock Drills assortment and forms a case study for our research. The slide bar is a thin steel profile which measures between two and eight centimetres. They are placed on the feeders of surface- and underground drilling rigs as a protection from wear and tear. Atlas Copco Shared Distribution Center (DC) has given us a case as a background for our research. The slide bars are bulky to handle, wrap and transport and for DC the flow appears to be ineffective and expensive. DC are experiencing problems within the material flow of slide bars and is puzzled why no improvement has been done, although the problems has been known to DC for over twelve years. Projects to improve the flow has been initiated but gone down the drains.

Over the last twenty years we have seen an increasing use of in-work tax subsidies to encourage labor supply among low-income groups. In Sweden, a non-targeted earned income tax credit was introduced in 2007, and was reinforced in 2008, 2009 and 2010. The stated motive of the reform was to boost employment; in particular to provide incentives for individuals to go from unemployment to, at least, part-time work. In this paper we try to analyze the extensive margin labor supply effects of the Swedish earned income tax credit reform up to 2008. For identification we exploit the fact that the size of the tax credit, as well as the resulting average tax rate, is a function of the municipality of residence and income if working. However, throughout the analysis we find placebo effects that are similar in size to the estimated reform effects. In addition, the results are sensitive with respect to how we define employment, which is especially true when we analyze different subgroups such as men and women, married and singles. Our conclusion is that the identifying variation is too small and potentially endogenous and that it is therefore not possible to use this variation to perform a quasi-experimental evaluation of the Swedish EITC-reform.

Integrated robust planning systems that cover all levels of SC hierarchy have become increasingly important. Strategic, tactical, and operational SC plans should not be generated in isolation to avoid infeasible and conflicting decisions. On the other hand, enterprise planning systems contain over millions of records that are processed in each planning iteration. In such enterprises, the ability to generate robust plans is vital to their success because such plans can save the enterprise resources that may otherwise have to be reserved for likely SC plan changes. A robust SC plan is valid in all circumstances and does not need many corrections in the case of interruption, error, or disturbance. Such a reliable plan is proactive as well as reactive. Proactivity can be achieved by forecasting the future events and taking them into account in planning. Reactivity is a matter of agility, the capability of keeping track of system behaviour and capturing alarming signals from its environment, and the ability to respond quickly to the occurrence of an unforeseen event. Modeling such a system behaviour and providing solutions after such an event is extremely important for a SC. This study focuses on integrated supply chain planning with stochastic dynamic considerations. An integrated tactical-operational model is developed and then segregated into two sub-models which are solved iteratively. A SC is a stochastic dynamic system whose state changes over time often in an unpredictable manner. As a result, the customer demand is treated as an uncertain parameter and is handled by exploiting scenario-based stochastic programming. The increase in the number of scenarios makes it difficult to obtain quick and good solutions. As such, a Branch and Fix algorithm is developed to segregate the stochastic model into isolated islands so as to make the computationally intractable problem solvable. However not all the practitioners, planners, and managers are risk neutral. Some of them may be concerned about the risky extreme scenarios. In view of this, the robust optimization approach is also adopted in this thesis. Both the solution robustness and model robustness are taken into account in the tactical model. Futhermore, the dynamic behaviour of a SC system is handled with the concept of Model Predictive Control (MPC).

Standard models in urban economics assume that the boundary of an urban area will expand as long as the present value of land for urban uses is greater than the present value of land for rural uses. Under this assumption, the boundary of the urban area is endogenously determined by the rent paid to rural landowners. But this assumption is not realistic. The physical expansion of many major urban areas in the United States is impeded by an exogenous boundary. For example, geographic growth of the three most populated metropolitan areas in the country is limited by an ocean or a Great Lake. In this thesis, we argue that such exogenous boundaries affect land prices throughout the urban area because inter-city migration is costly and these boundaries effectively constrain the supply of land. Specifically, we develop a theoretical model in support of this conclusion and show that prices are highest in cities with the most restrictive exogenous boundaries, ceteris paribus. This argument implies that researchers who do not control for exogenous boundaries could be introducing a systematic bias in their findings if they use land prices or rents to measure the value of public amenities in urban areas or the relative desirability of different cities.

This thesis aims to evaluate measurement techniques for delivery precision at Holmen Paper (HP). Delivery precision is an important KPI for a business, because it gives an indication of how well the company’s  supply chain is performing. At HP, the Operation and Logistics division, wants to use the result  to  assess  that  if  they  are  doing  a  good  job  planning  HP’s  production  and  transportation.   The purpose of the thesis: “The  purpose  of  the  thesis  is  to  determine  how  the  KPI  delivery  precision ought to be measured for  various  order  types  in  Holmen  Paper’s  supply  chain.” A great deal of literature was initially reviewed on the subject of delivery precision, and different sources suggested alternative ways in which it may be determined. To understand the logistics and information flow, two flow-charts where constructed. This was done in order to obtain a holistic overview  of  HP’s  order-delivery process, and furthermore, to see where the required data could be retrieved from the system. After evaluating the supply chain, it was concluded   that   the   SCOR   models’   pre-defined Key Performance Indicator Perfect Order Fulfillment (POF) and Perfect Order Index (POI), were the best way to measure the delivery precision. Both theories are well known in the logistics sector and both are built upon lower level metrics. The metrics measure if an order is delivered satisfactorily to a customer, according the parameters of time, quantity, quality and documentation. The thesis, however, rejected the parameter of documentation in dialogue with HP (and because the parameter has little to do with the operators work at Operation and Logistics). Data  was  collected  from  HP’s  database  in  an  attempt  to  measure  the  delivery  precision  according  to   both the theories. However, it was concluded that the calculated value was unreliable. This was mainly due to fact that the data required did not exist, and the data that did exist was not reliable. The data was seen as unreliable because there was no information of when the data was collected along the supply chain. Therefore, the thesis presents a model that will help HP implement the KPI delivery precision in the future. At the completion of the study, it was concluded that HP, initially, needs to implement a system to save data regarding the reason and source of order modifications. Additionally, it is suggested that HP should try to measure the delivery precision as close to the customer as possible. Currently, the data required to do this does not exist. To obtain this data, HP needs to implement some sort of receipt when the customer receives the goods.

We consider three problems on inventory, transportation and location in a supply chain. In Chapter 2, we study Multilevel Rationing (MR) and Strict Priority (SP) stock allocation policies for a centralized single product multi-class M/G/1 make-to-stock queueing systems. To obtain the total cost of the system under these policies, we introduce a new method called “customer composition”. Using this method, we focus on the proportion of customers of each class out of the total number of customers in the queue since the number of customers in M/G/1 queues is invariant for any non-idling and non-anticipating policy. We consider a series of two-priority M/G/1 queues with an exceptional service time in each busy period to characterize the customer composition. We derive closed form expressions for the costs of SP and MR policies using these results. In Chapter 3, we consider a two-echelon inventory system with a congested centralized production facility and several Distribution Centers (DCs). We assume that the production and transportation times are stochastic that are generally distributed, and customers arrive to each DC according to an independent Poisson process. Inventory at DCs is managed using the one-for-one replenishment policy. We use the customer composition approach to characterize the total inventory carrying and backlog costs of the system under the FCFS, SP and MR allocation policies at the warehouse. For the special case of exponentially distributed production and transportation times, we use the unit-flow method and derive closed form expressions for the optimal cost and base-stock level of the DCs. We numerically demonstrate that prioritization using either the SP or the MR policy could be very beneficial in comparison with the FCFS policy. In Chapter 4, we study a two-echelon supply chain with a set of suppliers, a set of retailers and a set of capacitated cross-docks which are to be established. The demand of the retailers could be satisfied from the suppliers through the cross-docks. The objective is to determine the number and location of cross-docks, the assignment of retailers to suppliers so that the total cost of pipeline and retailers’ inventory, transportation, and facility location is minimized. We formulate the problem as a non-linear mixed integer programming and derive several structural results for special cases of the problem. To solve the general problem, we show that it can be written as a cutting stock problem and develop a column generation algorithm to solve it. We investigate the efficiency of the proposed algorithm numerically.

No description available.

We consider three problems on inventory, transportation and location in a supply chain. In Chapter 2, we study Multilevel Rationing (MR) and Strict Priority (SP) stock allocation policies for a centralized single product multi-class M/G/1 make-to-stock queueing systems. To obtain the total cost of the system under these policies, we introduce a new method called “customer composition”. Using this method, we focus on the proportion of customers of each class out of the total number of customers in the queue since the number of customers in M/G/1 queues is invariant for any non-idling and non-anticipating policy. We consider a series of two-priority M/G/1 queues with an exceptional service time in each busy period to characterize the customer composition. We derive closed form expressions for the costs of SP and MR policies using these results. In Chapter 3, we consider a two-echelon inventory system with a congested centralized production facility and several Distribution Centers (DCs). We assume that the production and transportation times are stochastic that are generally distributed, and customers arrive to each DC according to an independent Poisson process. Inventory at DCs is managed using the one-for-one replenishment policy. We use the customer composition approach to characterize the total inventory carrying and backlog costs of the system under the FCFS, SP and MR allocation policies at the warehouse. For the special case of exponentially distributed production and transportation times, we use the unit-flow method and derive closed form expressions for the optimal cost and base-stock level of the DCs. We numerically demonstrate that prioritization using either the SP or the MR policy could be very beneficial in comparison with the FCFS policy. In Chapter 4, we study a two-echelon supply chain with a set of suppliers, a set of retailers and a set of capacitated cross-docks which are to be established. The demand of the retailers could be satisfied from the suppliers through the cross-docks. The objective is to determine the number and location of cross-docks, the assignment of retailers to suppliers so that the total cost of pipeline and retailers’ inventory, transportation, and facility location is minimized. We formulate the problem as a non-linear mixed integer programming and derive several structural results for special cases of the problem. To solve the general problem, we show that it can be written as a cutting stock problem and develop a column generation algorithm to solve it. We investigate the efficiency of the proposed algorithm numerically.

Integrated robust planning systems that cover all levels of SC hierarchy have become increasingly important. Strategic, tactical, and operational SC plans should not be generated in isolation to avoid infeasible and conflicting decisions. On the other hand, enterprise planning systems contain over millions of records that are processed in each planning iteration. In such enterprises, the ability to generate robust plans is vital to their success because such plans can save the enterprise resources that may otherwise have to be reserved for likely SC plan changes. A robust SC plan is valid in all circumstances and does not need many corrections in the case of interruption, error, or disturbance. Such a reliable plan is proactive as well as reactive. Proactivity can be achieved by forecasting the future events and taking them into account in planning. Reactivity is a matter of agility, the capability of keeping track of system behaviour and capturing alarming signals from its environment, and the ability to respond quickly to the occurrence of an unforeseen event. Modeling such a system behaviour and providing solutions after such an event is extremely important for a SC. This study focuses on integrated supply chain planning with stochastic dynamic considerations. An integrated tactical-operational model is developed and then segregated into two sub-models which are solved iteratively. A SC is a stochastic dynamic system whose state changes over time often in an unpredictable manner. As a result, the customer demand is treated as an uncertain parameter and is handled by exploiting scenario-based stochastic programming. The increase in the number of scenarios makes it difficult to obtain quick and good solutions. As such, a Branch and Fix algorithm is developed to segregate the stochastic model into isolated islands so as to make the computationally intractable problem solvable. However not all the practitioners, planners, and managers are risk neutral. Some of them may be concerned about the risky extreme scenarios. In view of this, the robust optimization approach is also adopted in this thesis. Both the solution robustness and model robustness are taken into account in the tactical model. Futhermore, the dynamic behaviour of a SC system is handled with the concept of Model Predictive Control (MPC).