Inventory management and production control problem of a dealer operating in a decentralized spare parts network is analyzed in this dissertation. Spare parts network is assumed to be formed of two dealers and the problem of a dealer is considered under the assumption that the other dealer has a known policy. These dealers collaborate through inventory and service pooling. Furthermore, the dealers collaborate through sharing information on the net inventory status. Upon demand arrival, a dealer may request a part from the other dealer, in which case a payment is made. Under this competitive and collaborative environment, the optimal operating policy of an individual dealer is characterized under full information. Through computational analysis, the conditions under which the dealer under consideration is most profitable are identified. Finally, by comparing dierent pooling strategies and several information availability levels, the benefit of information sharing is quantified.

Master’s thesis deals with the consolidation of financial statements and analysis of financial condition of group subjected to consolidated financial statements. Fundamental thesis goal is an assesment of financial position selected group of companies by methods of financial analysis and specialized models. It leads to finding potential weaknesses and creation of proposals leading to eliminate discovered weaknesses and improving the financial situation of group.

Stora koncerner med verksamhet i flera företag och inte sällan i flera länder kan gynnas av att styra hela koncernens ekonomi från en gemensam enhet. Moderbolaget har olika stor insyn i dotterbolagens verksamheter beroende på koncernens storlek och organisationsstruktur och därmed kan centralisering av likviditetsstyrningen ske på olika sätt. Syftet med uppsatsen är att ur ett ledarskapsperspektiv studera hur centraliserad likviditetsstyrning utförs samt hur det kan påverka koncerner. För att uppnå syftet har kvalitativa intervjuer genomförts med ekonomicheferna i fyra koncerner. Studien har därmed gjorts ur ett ledarskapsperspektiv och personliga intervjuer har gjorts för att få en djupare förståelse för hur koncernerna väljer att centralisera sin likviditetsstyrning samt vilken påverkan det har. Koncernerna som intervjuats har i hög grad centraliserad likviditetsstyrning och de viktigaste besluten fattas i huvudsak från en och samma enhet, resultatet av intervjuerna visar att centraliserad likviditetsstyrning skapar ökad översikt och kontroll. Ekonomicheferna anser sig ha god insyn i dotterbolagens verksamheter och kan därmed fatta de beslut som är de bästa för koncernen.  För att få en ökad förståelse för hur cash pooling kan användas som instrument för att centralisera likviditetsstyrningen intervjuades även två banker. Cash pooling ger en översiktlig bild över koncernens likviditet genom interna överföringar mellan konton med intern ränta. Därmed används det befintliga kapitalet på ett effektivt sätt innan externa lån behöver tas. Tre av koncernerna använder sig av cash pooling och de anser att det skapar en överskådlighet över koncernens likviditet samt en ökad effektivitet eftersom antalet externa banklån reduceras. Bankerna är eniga och menar att cash pooling skapar en samlad bild över koncernens likviditet. Utöver cash pooling tar studien även upp begrepp som centralisering, cash management och treasury management, vilka även de kan ses som sätt att effektivisera likviditetsstyrningen i en koncern. / Business groups with companies active in several countries can benefit from managing the entire group’s economy from one single entity. The parent company’s transparency of its subsidiaries is depending on the size and the organizational structure of the concern. Therefore, centralization of the liquidity can be done in several ways. The purpose of the study aims to clarify how centralization of the liquidity can be performed and what consequences it gives the concern. The study has been conducted through the leaders’ perspectives of the business groups. Interviews have been carried out with the financial chiefs of four business groups, in order to get a deeper knowledge of how the liquidity is centralized and what effects it brings. The business groups have in a great extent centralized their liquidity to one entity where the most important decisions are made. The financial chiefs consider themselves to have the right knowledge to make decisions with the concern’s best interest in mind. To get a deeper knowledge about centralization of liquidity from the perspectives of the banks, and also to get awareness of cash pooling and how it is used, the decision of interviewing two banks as well, was made. Cash pooling is an instrument for optimizing the liquidity within business groups and thereby enabling an effective management of cash, and reducing the need for external borrowings. Three out of the four concerns interviewed are users of cash pooling and they all consider it an effective instrument that creates transparency and control over the liquidity. The banks agree and say that it gives a more composed picture of the liquidity of the concern, which simplifies the contact with the bank. In addition to cash pooling, the study also discusses cash management and treasury management. In conclusion, it is clear to say that there are considerable advantages, such as a greater transparency and control, when a corporate group is centralizing its liquidity. It also creates legitimacy against banks.

Au cours des vingt dernières années, le secteur des services est devenu le secteur le plus important en nombre d'actifs occupés dans l’économie mondiale, en particulier dans les pays développés. Par ailleurs, la concurrence et la coopération dans le secteur des services sont devenues de plus en plus populaires dans le contexte de la mondialisation économique. Comment collaborer avec un accord gagnant-gagnant apporte une source fertile de problèmes de management des opérations dans le domaine des services. Dans cette thèse, nous étudions des stratégies de collaboration dans des systèmes de services homogènes. Nous nous concentrons en particulier sur les stratégies de pooling des ressources de service.Dans les deux premières parties, nous étudions le problème de partage des coûts entre les fournisseurs de services indépendants avec des temps de service qui suivent une distribution générale et en tenant compte de l'abandon des clients. Nous modélisons à la fois chaque fournisseur de services et la coalition coopérative comme des files d'attente avec serveur unique, et spécialisons les stratégies de pooling avec les capacités de services fixes et modifiables. Dans la dernière partie, nous abordons le problème de pooling dans le cadre multiserveur pour évaluer la qualité de l'hypothèse "superserveur". Nous étudions numériquement l'impact de la variabilité de la durée de service et l'abandon des clients sur les jeux de mise en commun des ressources. Nous comparons aussi les partages des coûts entre le système de "super-serveur" et multiserveur. / In past twenty years, the service sector has emerged as the primary sector in the world economy, especially in developed countries. Competition and cooperation in service industries have become more and more popular in the context of economic globalization. How to operate the collaboration with a win-win agreement brings a fertile source of operations management issues in service science. In this thesis, we study collaborations between homogeneous service systems in terms of resource pooling strategies.In the first two parts, we investigate the cost-sharing problem among independent service providers with general service times and accounting for the customer abandonment. We model both the service provider and the cooperative coalition as single server queues, and specialize the capacity pooling strategies with the fixed and optimized service capacities.Finally, we address the service pooling problem in the multi-serverpooling setting to assess the quality of the "super-server" assumption.We numerically investigate the impact of service duration variability and customer abandonment on the pooling game. We compare between cost-sharing results of the two resource pooling concepts, with or without the "super-server" assumptions.

Background and Aims The accurate differentiation between a delayed pharyngeal swallow (sensory impairment) and premature spillage secondary to poor oro-lingual control (motor impairment) is essential to effective dysphagia management. However both physiologic abnormalities result in an identical radiographic sign, that of pre-swallow pooling of the bolus in the pharynx. The dysphagia literature does not provide satisfactory guidelines for making this distinction on videofluoroscopy. The purpose of this study was to assess the validity of a three-part rating scale for differentiating between these two impairments. Methods Videofluoroscopy was used to evaluate the swallowing of 29 participants presenting with dysphagia following stroke. Sensory thresholds for these participants were established by electrical stimulation of the anterior faucial pillars. The videofluoroscopic swallowing studies were analysed using the three-part rating scale and results from this were compared to sensory thresholds using Pearson's product moment correlation. Results There was no significant correlation between the three-part criteria and sensory thresholds. Inter-rater reliability for some measures was poor. Conclusions The three-part criteria was not shown to be a valid measure for differentiating between delayed pharyngeal swallow and premature spillage secondary to poor oro-lingual control. Possible explanations for these findings are discussed, including the relevance of faucial pillar sensation to swallowing.

The purpose of this thesis is to efficiently solve real life problems. We study LPs. We study an NLP and an MINLP based on what is known as the generalised pooling problem (GPP), and we study an MIP that we call the cattle mating problem. These problems are often very large or otherwise difficult to solve by direct methods, and are best solved by decomposition methods. During the thesis we introduce algorithms that exploit the structure of the problems to decompose them. We are able to solve row-linked, column-linked and general LPs efficiently by modifying the tableau simplex method, and suggest how this work could be applied to the revised simplex method. We modify an existing sequential linear programming solver that is currently used by Format International to solve GPPs, and show the modified solver takes less time and is at least as likely to find the global minimum as the old solver. We solve multifactory versions of the GPP by augmented Lagrangian decomposition, and show this is more efficient than solving the problems directly. We introduce a decomposition algorithm to solve a MINLP version of the GPP by decomposing it into NLP and ILP subproblems. This is able to solve large problems that could not be solved directly. We introduce an efficient decomposition algorithm to solve the MIP cattle mating problem, which has been adopted for use by the Irish Cattle Breeding Federation. Most of the solve methods we introduce are designed only to find local minima. However, for the multifactory version of the GPP we introduce two methods that give a good chance of finding the global minimum, both of which succeed in finding the global minimum on test problems.

Cette recherche vise à mieux connaitre les facteurs psychologiques d’installation des troubles du comportement alimentaire restrictif précoce. Après une présentation des différents enjeux psychologiques compris dans la relation parents/nourrisson, l’étude approfondie des interactions parents/nourrisson au moment de l’alimentation et une revue de la question dans la littérature internationale, trois facteurs d’installation des troubles du comportement alimentaire précoce peuvent être dégagés. Le premier est représenté par le partage d’expériences affectives compris dans la dynamique interactive parents/nourrisson. Le second est représenté par la co-excitation parents/nourrisson comprise dans la mutualisation des investissements libidinaux. Le troisième est représenté par la co-emprise parent/nourrisson comprise dans la mutualisation des investissements libidinaux. L’hypothèse de cette recherche est que le trouble du comportement alimentaire précoce dépend du niveau de co-excitation et de co-emprise parents/nourrisson associé à la mutualisation des investissements libidinaux parents/nourrisson. Du point de vue méthodologique, cette recherche s’appuie sur six études de cas présentées selon les paradigmes de la psychanalyse et de l’observation du nourrisson à partir de la classification de l’école de Washington. / This research aims at better knowing the psychological factors of settlement of the disorders of early restrictive eating behavior. After a presentation of the various psychological stakes included in the parents/infant relationship, the thorough study of the parents/infant interactions during feeding time and a review of this issue in the international literature, three factors of settlement of the disorders of early eating behavior can be released. The first is represented by the sharing of emotional experiments included in the parents/infant interactive dynamics. The second is represented by the parents/infant co-excitation included in the pooling of the libidinous investments. The third is represented by the parents/infant co-influence included in this pooling of the libidinous investments. The assumption of this research is that the disorder of early eating behavior depends on the level of parents/infant co-excitation and co-influence together with the pooling of the libidinous investments parents/infant. From the methodological point of view, this research is based on six case studies presented according to the paradigms of the psychoanalysis and of the observation of the infant as based on the school of Washington’s classification.

We study risk pooling via unidirectional lateral transshipments between two locations under local decision-making. Unidirectional transshipments can be applicable when cost structures and/or capabilities differ between locations, and it is also a common practice in dual channel supply chains with online and offline sales channels. We show that such a system cannot be coordinated only with varying transshipment prices. The transshipment receiver orders more and the transshipment giver orders less than the respective optimal centralised order quantities. In order to remove this discrepancy, we suggest horizontal coordinationmechanisms by introducing a leftover subsidy for the location providing the transshipments or a shortage subsidy for the location receiving transshipments as well as a combination of shortage and leftover subsidy. Further, we evaluate the impact of network structure by comparing the equilibrium order quantities and profits under the uni- and bidirectional systems as well as a system without transshipments. Since demand correlation is a critical aspect in risk pooling we provide a detailed numerical study to discuss its impact on our findings.

La logistique urbaine, considérée comme la dernière étape de la supply chain, recouvre toute prestation concourant à une gestion optimisée des flux de marchandises en milieu urbain. Le transport de marchandises a des effets négatifs importants dans les zones urbaines en termes de congestion, d'émissions nocives et de consommation d'espace. Pour atténuer ces effets, une collaboration entre les différents acteurs de la logistique urbaine a souvent été initiée dans de nombreuses villes. La collaboration dans les projets de logistique urbaine est difficile, elle nécessite de réunir de nombreuse parties prenantes dont les intérêts sont souvent divergents. Ces dernières années, la mutualisation logistique est apparue comme une stratégie qui mène à une collaboration systématique entre acteurs. Cependant, elle a peu été étudiée dans le contexte urbain L’objectif de cette thèse est de proposer une réflexion sur la conception d’une logistique urbaine innovante grâce à la mutualisation. Pour cela, nous avons effectué un état de l’art systématique afin d’identifier les différents champs de la logistique urbaine. Selon les résultats de cette revue de la littérature, nous avons constaté une absence d'analyse sur les aspects opérationnels de la mutualisation. Afin de remédier à ce manque, nous avons proposé un cadre général qui aide à identifier toutes les mesures nécessaires en vue d'une mutualisation efficace. Nous avons développé un nouveau concept, appelé « typologie des flux » permettant d’analyser différentes possibilités de mutualisation en logistique urbaine et ensuite d’identifier les contraintes potentielles liées à la mutualisation. Nous avons quantifié les effets de ces contraintes sur l'efficacité de la mutualisation utilisant un cas réel issu de la littérature. Enfin, nous avons mobilisé notre typologie des flux et les résultats de notre analyses expérimentales afin de classifier les facteurs clés permettant d’aborder la viabilité de la mutualisation à long terme. / City logistics, considered as the last step of supply chain management, aims to optimally plan, manage and control the freight movements within a logistical network in urban areas. Freight transportation causes significant negative impacts on the quality of living in urban areas in terms of congestion, emissions and space consumption. Collaboration has been introduced to alleviate these negative impacts; however, collaboration in city logistics projects is challenging, since additional efforts of planning and control of collaboration are significant. In recent years, pooling has emerged as a collaborative strategy that leads towards systematic collaboration between stakeholders involved while they are well-informed about the processes and have direct influence on decision making.The aim of this thesis is to study possible forms of pooling in the context of city logistics in order to analyse conditions for an efficient pooling implementation. To this end, we have conducted a comprehensive literature review on city logistics in order to analyse and classify its different aspects. Surveying the literature also conducted to identify a lack of systematic analysis on pooling in city logistics. In order to overcome this research gap, we have proposed a general stepwise framework that aids to identify all necessary steps toward an efficient pooling implementation. Furthermore, we have introduced a novel concept, called ‘typology of flow’, to analyse different possibilities of logistics pooling at a first step and to identify potential constraints before pooling implementation at a second step. We have quantified the impacts of these constraints on the efficiency of pooling using a real case raised from the literature. At the end, we have used our proposed framework, novel concept of typology of flow and results obtained from our experimental analysis in order to classify important factors for city logistics pooling viability in long term.

In this paper, we study the stochastic transportation-inventory network design problem involving one supplier and multiple retailers. Each retailer faces some uncertain demand. Due to this uncertainty, some amount of safety stock must be maintained to achieve suitable service levels. However, risk-pooling benefits may be achieved by allowing some retailers to serve as distribution centers (and therefore inventory storage locations) for other retailers. The problem is to determine which retailers should serve as distribution centers and how to allocate the other retailers to the distribution centers. Shen et al. (2000) and Daskin et al. (2001) formulated this problem as a set-covering integer-programming model. The pricing subproblem that arises from the column generation algorithm gives rise to a new class of submodular function minimization problem. They only provided efficient algorithms for two special cases, and assort to ellipsoid method to solve the general pricing problem, which run in O(n⁷ log(n)) time, where n is the number of retailers. In this paper, we show that by exploiting the special structures of the pricing problem, we can solve it in O(n² log n) time. Our approach implicitly utilizes the fact that the set of all lines in 2-D plane has low VC-dimension. Computational results show that moderate size transportation-inventory network design problem can be solved efficiently via this approach. / Singapore-MIT Alliance (SMA)