Thesis (M. Soc. Sc.)--University of Hong Kong, 1985.

This study is based on the strategic and logistical challenges of having a complex distribution network, which can make it difficult to get a holistic view over the distribution costs. The costs are often aggregated for many products, which makes it challenging to use as decision support on a product level. Many companies lack a tool to handle this complexity, since the costs and profitability varies between the channels and intermediaries used. This makes it problematic to determine the profitability on a product level. In the different parts of the distribution chain, there are elements that drive the costs for each activity, called activity drivers. When these activity drivers have been identified, they can be used to allocate the distribution costs to the different products. The aim of this study is to develop a tool that can be used to categorize distribution costs and to determine which activity drivers that result in the fairest cost allocation. The fairest cost allocation is a complex expression, and is briefly defined as the allocation key that result in a costs allocation that represent each products level of resource consumption. This means that products that have consumed a large amount of resources should carry a larger part of the costs compared to the products that have consumed a smaller amount of resources. Sometimes it is not obvious which allocation key that represents the reality in the fairest way, and in that case, the allocated costs are compared to the products sales values. The sales value often differs between the products. The determined allocation key is the one that result in the most even allocation when comparing the allocated cost to the sales values. The case company Swedish Orphan Biovitrum (Sobi) is located in Stockholm, Sweden. They find it difficult to get a view over the costs for the different parts of the distribution chain, and to allocate the costs fair between the products. This study have investigated the distribution from Sobi’s central warehouse in the Netherlands to the end customers in France, Germany, Italy, Spain, the United Kingdom via the local storages in each country, as well as Sweden and Estonia. This was done by categorizing the costs for each activity in the invoices from the local storages, into different cost categories. After this, the costs were allocated with different allocation keys that thereafter were compared, to find the most fair allocation key per category. In the end of this study, the lessons learned and methods used have been written down, and an allocation tool has been developed. Any company that wants to make strategic decisions on a product level can use this tool. Throughout the study, the five steps that make up the allocation tool have been followed. The tool is divided into the following steps; determination of cost categories, choice of activities, selection of activity drivers, categorization of costs and analyzing activity drivers. When choosing allocation key, it is essential to find the balance between an even allocation of the costs between the products, and to make sure that the allocation represent each products level of resource consumption. If the allocation is unfair, it can make products look unprofitable, even though they actually are profitable and necessary in reality. The difficulties to find a balance show the complexity in the determination of the most fair allocation key, since it is not always obvious. If the cost categories had been divided into smaller categories with more similar activity drivers, the dilemma of choosing allocation key might have been solved. However, it is important to bear in mind that when using more cost categories, the categorization and allocation becomes more time consuming. The tool has been created as a result of this study, and is based on a complex situation, which means that assumptions and simplifications have been made to be able to draw general conclusions. It is important to bare these simplifications in mind, when applying the tool to other situations than the one investigated in this study. The allocation tool can be used to draw strategic conclusions on a product level, since it makes it possible to be aware of the profitability of the products and, if necessary, exclude unprofitable products from the product assortment.

Theoretical considerations and empirical results show that the one-dimensional quality of non-uniform random numbers is bad and the discrepancy is high when they are generated by the ratio of uniforms method combined with linear congruential generators. This observation motivates the suggestion to replace the ratio of uniforms method by transformed rejection (also called exact approximation or almost exact inversion), as the above problem does not occur for this method. Using the function $G(x) =\left( \frac(a)(1-x)+b\right)x $ with appropriate $a$ and $b$ as approximation of the inverse distribution function the transformed rejection method can be used for the same distributions as the ratio of uniforms method. The resulting algorithms for the normal, the exponential and the t-distribution are short and easy to implement. Looking at the number of uniform deviates required, at the code length and at the speed the suggested algorithms are superior to the ratio of uniforms method and compare well with other algorithms suggested in literature. (author's abstract) / Series: Preprint Series / Department of Applied Statistics and Data Processing

published_or_final_version / Urban Studies / Master / Master of Social Sciences

Η παρούσα μεταπτυχιακή διατριβή διαπραγματεύεται τη μελέτη της κατανομής Pareto, την εκτίμηση και την σύγκριση των εκτιμητών των παραμέτρων της καθώς και την εκτίμηση της συνάρτησης επιβίωσης της δεδομένου ότι η κατανομή Pareto χρησιμοποιείται ως μοντέλο για την εκτίμηση μεγάλων εισοδημάτων. Στο Κεφάλαιο 1, παραθέτουμε μερικούς βασικούς ορισμούς και θεωρήματα της Μαθηματικής Στατιστικής όπου είναι αναγκαία για την ανάπτυξη της εργασίας μας. Στο Κεφάλαιο 2, αναφερόμαστε στη κατανομή Pareto, στα γενικά χαρακτηριστικά της και τη συσχέτισή της με άλλες γνωστές κατανομές. Στο Κεφάλαιο 3, μελετάμε τους εκτιμητές των παραμέτρων της κατανομή Pareto ως προς το τετραγωνικό σφάλμα κάνοντας και κάποιες συγκρίσεις μεταξύ των εκτιμητών. Στο Κεφάλαιο 4, μελετάμε τους εκτιμητές Bayes των παραμέτρων της κατανομή Pareto με συνάρτηση σφάλματος LINEX και τους συγκρίνουμε με τους εκτιμητές Bayes με τετραγωνικό σφάλμα. Στο Κεφάλαιο 5, εκτιμάμε της συνάρτηση επιβίωσης και μελετάμε τους αμερόληπτους εκτιμητές ελάχιστης διασποράς της πυκνότητας πιθανότητας και της συνάρτησης κατανομής συγκρινόντας τους, στη συνέχεια, με τους αντίστοιχους εκτιμητές μέγιστης πιθανοφάνειας. Στο Κεφάλαιο 6, παρουσιάζουμε ένα παράδειγμα για την καλύτερη κατανόηση των εκτιμήσεων μας. / We make an estimation for the Pareto distribution, we estimate the parameters of it and we make comparisons with each other.

The thesis examines the establishment size distribution over time and across groups of regions, using data on Swedish establishments during period 1994-2009. The size distribution of establishments is highly skewed and approximates the Pareto distribution. The shape of size distribution is invariant over time and across groups of regions. The distribution of total number of establishments and incumbent distribution are found to rise from the same distribution. Moreover, the invariance of establishment size distribution is highly determined by the invariance of distribution of incumbents, entry and exit distributions. Larger establishments have more chances to survive and higher probability to remain in current size group comparing to smaller ones, whereas higher probabilities of growth would be attached to smaller establishments.

No description available.

Unconventional oil and gas, which is of major interest in petroleum industry, often occur in reservoirs with transversely isotropic rock properties such as shales. Overlooking transverse isotropy may result in deviation in stress distribution around wellbore and inaccurate estimation of fracture initiation pressure which may jeopardize safe drilling and efficient fracturing treatment. In this work, to help understand the behavior of transversely isotropic reservoirs during drilling and fracturing, the principle of generalized plane-strain finite element formulation of anisotropic poroelastic problems is explained and a finite element model is developed from a plane-strain isotropic poroelastic model. Two numerical examples are simulated and the finite element results are compared with a closed form solution and another FE program. The validity of the developed finite element model is demonstrated. Using the validated finite element model, sensitivity analysis is carried out to evaluate the effects of transverse isotropy ratios, well azimuth, and rock bedding dip on pore pressure and stress distribution around a horizontal well. The results show that their effect cannot be neglected. The short term pore pressure distribution is sensitive to Young’ modulus ratio, while the long term pore pressure distribution is only sensitive to permeability ratio. The total stress distribution generally is not sensitive to transverse isotropy ratios. The effective stress and fracture initiation are very sensitive to Young’ modulus ratio. As the well rotates from minimum horizontal in-situ stress to maximum horizontal in-situ stress, the pore pressure and stress distributions tend to be more unevenly distributed around the wellbore, making the wellbore easier to fracture. The pore pressure and stress distributions tend to "rotate" in correspondence with the rock bedding plane. The fracture initiation potential and position will alter when rock bedding orientation varies.

Assignment (MComm)--University of Stellenbosch, 2007. / Bibliography. Also available via the Internet.

Thèse (M.Ress.Renouv.) -- Université du Québec à Chicoutimi, 2005. / Bibliogr.: f. 79-85. Document électronique également accessible en format PDF. CaQCU