L’industrie forestière est un secteur qui, même s’il est en déclin, se trouve au cœur du débat sur la mondialisation et le développement durable. Pour de nombreux pays tels que le Canada, la Suède et le Chili, les objectifs sont de maintenir un secteur florissant sans nuire à l’environnement et en réalisant le caractère fini des ressources. Il devient important d’être compétitif et d’exploiter de manière efficace les territoires forestiers, de la récolte jusqu’à la fabrication des produits aux usines, en passant par le transport, dont les coûts augmentent rapidement. L’objectif de ce mémoire est de développer un modèle de planification tactique/opérationnelle qui permet d’ordonnancer les activités pour une année de récolte de façon à satisfaire les demandes des usines, sans perdre de vue le transport des quantités récoltées et la gestion des inventaires en usine. L’année se divise en 26 périodes de deux semaines. Nous cherchons à obtenir les horaires et l’affectation des équipes de récolte aux blocs de coupe pour une année. Le modèle mathématique développé est un problème linéaire mixte en nombres entiers dont la structure est basée sur chaque étape de la chaine d’approvisionnement forestière. Nous choisissons de le résoudre par une méthode exacte, le branch-and-bound. Nous avons pu évaluer combien la résolution directe de notre problème de planification était difficile pour les instances avec un grand nombre de périodes. Cependant l’approche des horizons roulants s’est avérée fructueuse. Grâce à elle en une journée, il est possible de planifier les activités de récolte des blocs pour l’année entière (26 périodes). / Forest industry is a sector located at the heart of the debate on globalisation and sustainable development, even if it is in decline. For many countries like Canada, Sweden and Chile, the objectives are to maintain a flourishing sector without damaging the environment and to realize the finite nature of resources. It is important to be competitive and to operate effectively on forest territories, from harvesting to manufacturing products, through transport, in a context where costs increase rapidly. This master’s thesis is developing a tactical operational planning model to organize activities for a year to meet requests for factories, without losing sight of the transport of harvested quantities and inventory management factory. The year is divided into 26 periods of two weeks. We seek harvest teams schedules and assignment to harvest areas (units) for a year. The problem is formulated as a mixed integer programming model, whose structure is based on each stage of the forest supply chain. We choose to solve it by an exact method, branch-and-bound. We were able to assess how the direct resolution of our planning problem was difficult for instances with a large number of periods. However the rolling horizon approach has proved successful. In a day, we obtained the harvest activities planning for 26 periods.

The work presented in this dissertation has been focused on exploiting the branch-and-price (BNP) method for the solution of various stochastic mixed integer programming problems (MIPs). In particular, we address the stochastic generalized assignment problem (SGAP), a hospital staff scheduling problem (HSSP), a stochastic hospital staff scheduling problem (SHSSP), and a stochastic short-term personnel planning problem (SSTPP). The BNP method has been developed in concert with the dual stabilization technique and other enhancements of this method for each of these problems. In view of an excessive number of scenarios that arise for these problems, we also implement the Monte Carlo method within the BNP scheme. The superiority of the BNP-based method over the branch-and-cut (BNC) method is demonstrated for all of these problems. The first problem that we address is the SGAP for which the processing time of a job on a machine is assumed to be stochastic. Even though the generalized assignment problem (GAP) has been solved using the BNP method, yet no study has been reported in the literature on the use of the BNP method for the solution of the SGAP. Our work has been motivated by the desire to fill this gap. We begin by showing that it is better to solve the SGAP as a stochastic program in contrast to solving it by using the expected values of the times required to process the jobs on the machines. Then, we show that the stochastic model of the SGAP is a complete recourse model — a useful property which permits the first stage decisions to produce feasible solutions for the recourse problems. We develop three BNP-based methods for the solution of the SGAP. The first of these is BNP-SGAP, which is a combination of branch-and-bound and column generation methods. The pricing problem of BNP-SGAP is separable with regard to each machine, and it is a multiple-constraint knapsack problem. The second method is BNP-SGAP implemented in concert with the dual stabilization technique (DST), and it is designated as BNPDST-SGAP. We have introduced a new DST by modifying the Boxstep method of Pigatti et al. [76]. We have shown that our method performs better than the method of Pigatti et al. [76] resulting in over two-fold savings in cpu times on average. The third method that we develop for the solution of the SGAP is BNPDST-SGAP implemented with an advanced start to obtain an initial feasible solution. We use a greedy heuristic to obtain this solution, and this heuristic is a modification of a similar method used for the knapsack problem. It relies on the information available at a node of the underlying branch-and-bound tree. We have shown that this procedure obtains an initial feasible solution, if it exists at that node. We designate this method as BNPDSTKP-SGAP. We have also developed a BNC method to solve the SGAP using CPLEX 9.0. We have compared the performances of the BNP and BNC methods on various problem instances obtained by varying the number of machines, the ratio of the number of machines to the number of jobs, the machine capacity, and the penalty cost per unit of extra resource required at each machine. Our results show that all BNP-based methods perform better than the BNC method, with the best performance obtained for BNPDSTKP-SGAP. An issue with the use of the scenario-based methods that we have employed for the solution of the SGAP is that the number of scenarios generally grows exponentially in problem parameters, which gives rise to a large-size problem. To overcome the complexity caused by the presence of a large number of scenarios for the solution of the SGAP, we introduce the use of the Monte Carlo method (MCM) within the BNP scheme. We designate this method as BNPDSTKP-SGAP with MCM. It affords the use of a small subset of scenarios at a time to estimate the "true" optimal objective function value. Replications of the subsets of scenarios are carried out until the objective function value satisfies a stopping criterion. We have established theoretical results for the use of the MCM. These pertain to determining unbiased estimates of: (i) lower and upper bounds of the "true" optimal objective function value, (ii) the "true" optimal solution, and (iii) the optimality gap. We have also provided the 100(1-ï ¡) confidence interval on the optimality gap. Our experimental investigation has shown the efficacy of using this method. It obtains almost optimal solutions, with the objective function value lying within 5% of the "true" optimal objective function value, while giving almost ten-fold savings in cpu time. Our experimentation has also revealed that an increment in the number of scenarios in each replication makes a greater impact on the quality of the solution obtained than an increment in the number of replications. We have also observed the impact of a change in the variance of a processing time distribution on cpu time. As expected, the optimal objective function value increases with increment in processing time variability. Also, by comparing the results with the expected value solution, it is observed that the greater the variability in the data, the better it is to use the stochastic program. The second problem that we study is the hospital staff scheduling problem. We address the following three versions of this problem: HSSP (General): Implementation of schedule incorporating the four principal elements, namely, surgeons, operations, operating rooms, and operation times; HSSP (Priority): Inclusion of priority for some surgeons over the other surgeons regarding the use of the facility in HSSP (General); HSSP (Pre-arranged): Implementation of a completely pre-fixed schedule for some surgeons. The consideration of priority among the surgeons mimics the reality. Our BNP method for the solution of these problems is similar to that for the SGAP except for the following: (i) a feasible solution at a node is obtained with no additional assignment, i.e., it consists of the assignments made in the preceding nodes of that node in the branch-and-bound tree; (ii) the columns with positive reduced cost are candidates for augmentation in the CGM; and (iii) a new branching variable selection strategy is introduced, which selects a fractional variable as a branching variable by fixing a value of which we enforce the largest number of variables to either 0 or 1. The priority problem is separable in surgeons. The results of our experimentation have shown the efficacy of using the BNP-based method for the solution of each HSSP as it takes advantage of the inherent structure of each of these problems. We have also compared their performances with that of the BNC method developed using CPLEX. For the formulations HSSP (General), HSSP (Priority), and HSSP (Pre-arranged), the BNP method gives better results for 22 out of 30, 29 out of 34, and 20 out 32 experiments over the BNC method, respectively. Furthermore, while the BNC method fails to obtain an optimal solution for 15 experiments, the BNP method obtains optimal solutions for all 96 experiments conducted. Thus, the BNP method consistently outperforms the BNC method for all of these problems. The third problem that we have investigated in this study is the stochastic version of the HSSP, designated as the Stochastic HSSP (SHSSP), in which the operation times are assumed to be stochastic. We have introduced a formulation for this formulation, designated as SHSSP2 (General), which allows for overlapping of schedules for surgeons and operating rooms, and also, allows for an assignment of a surgeon to perform an operation that takes less than a pre-arranged operation time, but all incurring appropriate penalty costs. A comparison of the solution of SHSSP2 (General) and its value with those obtained by using expected values (the corresponding problem is designated as Expected-SHSSP2 (General)) reveals that Expected-SHSSP2 (General) may end up with inferior and infeasible schedules. We show that the recourse model for SHSSP2 (General) is a relatively complete recourse model. Consequently, we use the Monte Carlo method (MCM) to reduce the complexity of solving SHSSP2 (General) by considering fewer scenarios. We employ the branch-and-cut (BNC) method in concert with the MCM for solving SHSSP2 (General). The solution obtained is evaluated using tolerance ratio, closeness to optimality, length of confidence interval, and cpu time. The MCM substantially reduces computational effort while producing almost optimal solutions and small confidence intervals. We have also considered a special case of SHSSP2 (General), which considers no overlapping schedules for surgeons and operating rooms and assigns exactly the same operation time for each assignment under each scenario, and designate it as SHSSP2 (Special). With this, we consider another formulation that relies on the longest operation time among all scenarios for each assignment of a surgeon to an operation in order to avoid scheduling conflicts, and we designate this problem as SHSSP (Longest). We show SHSSP (Longest) to be equivalent to deterministic HSSP, designated as HSSP (Equivalent), and we further prove it to be equivalent to SHSSP (General) in terms of the optimal objective function value and the optimal assignments of operations to surgeons. The schedule produced by HSSP (Equivalent) does not allow any overlap among the operations performed in an operating room. That is, a new operation cannot be performed if a previous operation scheduled in that room takes longer than expected. However, the schedule generated by HSSP (Equivalent) may turn out to be a conservative one, and may end up with voids due to unused resources in case an operation in an operating room is completed earlier than the longest time allowed. Nevertheless, the schedule is still a feasible one. In such a case, the schedule can be left-shifted, if possible, because the scenarios are now revealed. Moreover, such voids could be used to perform other procedures (e.g., emergency operations) that have not been considered within the scope of the SHSSP addressed here. Besides, such a schedule can provide useful guidelines to plan for resources ahead of time. The fourth problem that we have addressed in this dissertation is the stochastic short-term personnel planning problem, designated as Stochastic STPP (SSTPP). This problem arises due to the need for finding appropriate temporary contractors (workers) to perform requisite jobs. We incorporate uncertainty in processing time or amount of resource required by a contractor to perform a job. Contrary to the SGAP, the recourse model for this problem is not a relatively complete recourse model. As a result, we cannot employ a MCM method for the solution of this problem as it may give rise to an infeasible solution. The BNP method for the SSTPP employs the DST and the advanced start procedure developed for the SGAP, and due to extra constraints and presence of binary decision variables, we use the branching variable selection strategy developed for the HSSP models. Because of the distinctive properties of the SSTPP, we have introduced a new node selection strategy. We have compared the performances of the BNC-based and BNP-based methods based on the cpu time required. The BNP method outperforms the BNC method in 75% of the experiments conducted, and the BNP method is found to be quite stable with smaller variance in cpu times than those for the BNC method. It affords solution of difficult problems in smaller cpu times than those required for the BNC method. / Ph. D.

An essential blend between competencies, personality and skill is sought after for successful branch managers in today’s banking world in order to achieve a high level of quality, on-time delivery, as well as customer and employee satisfaction and loyalty. In this study the predictive relationship between competencies (as a portrayal of personality and abilities) and work performance was investigated among the branch managers. The scores on the essential Universal Competency Framework competencies, the Person- Job Match and performance data for three years were used to conduct correlation and regression analyses. The study was conducted among 95 branch managers at a banking institution in South Africa. A theoretical relationship was determined, and this was supported by the significant relationship that was evident between the identified essential competencies of the branch managers and their work performance. The regression model summary indicated significance when using all essential competencies combined against the overall criterion score. / Industrial & Organisational Psychology / M.A. (Industrial and Organisational Psychology)

Central to the study of Life is knowledge both about the underlying relationships among living things and the processes that have molded them into their diverse forms. Phylogenetics provides a powerful toolkit for investigating both aspects. Bayesian phylogenetics has gained much popularity, due to its readily interpretable notion of probability. However, the posterior probability of a phylogeny, as well as any dependent biological inferences, is conditioned on the assumed model of evolution and its priors, necessitating care in model formulation. In Chapter 1, I outline the Bayesian perspective of phylogenetic inference and provide my view on its most outstanding questions. I then present results from three studies that aim to (i) improve the accuracy of Bayesian phylogenetic inference and (ii) assess when the model assumed in a Bayesian analysis is insufficient to produce an accurate phylogenetic estimate. As phylogenetic data sets increase in size, they must also accommodate a greater diversity of underlying evolutionary processes. Partitioned models represent one way of accounting for this heterogeneity. In Chapter 2, I describe a simulation study to investigate whether support for partitioning of empirical data sets represents a real signal of heterogeneity or whether it is merely a statistical artifact. The results suggest that empirical data are extremely heterogeneous. The incorporation of heterogeneity into inferential models is important for accurate phylogenetic inference. Bayesian phylogenetic estimates of branch lengths are often wildly unreasonable. However, branch lengths are important input for many other analyses. In Chapter 3, I study the occurrence of this phenomenon, identify the data sets most likely to be affected, demonstrate the causes of the bias, and suggest several solutions to avoid inaccurate inferences. Phylogeneticists rarely assess absolute fit between an assumed model of evolution and the data being analyzed. While an approach to assessing fit in a Bayesian framework has been proposed, it sometimes performs quite poorly in predicting a model’s phylogenetic utility. In Chapter 4, I propose and evaluate new test statistics for assessing phylogenetic model adequacy, which directly evaluate a model’s phylogenetic performance. / text

Darbe apžvelgiama trimačio pakavimo problemos tipologija. Nagrinėjama trimečio konteinerių pakavimo problema ir jos sprendimo būdai. Pateikiama šakos ir ribos, bei tabu paieškos algoritmų formulavimas ir jų rezultatų analizė. / The paper gives an overview of three-dimensional packing problem typology. There are investigating issue of container packing problem and its solutions. Branch and bound, TSpack algorithms formulation and analysis of their results.

Les succursales implantées dans un pays étranger sont plus autonomes que leurs consoeurs situées dans le même pays que la maison mère. Elles évoluent dans un environnement juridique différent et par conséquent les liens avec la maison mère sont distendus. Le tribunal de l’Etat d’accueil de la succursale est compétent et les lois de ce pays sont applicables. Toutefois, les lois du pays d’accueil ne sont pas les seules à être applicables. L’absence de personnalité juridique des succursales aura pour conséquence la sollicitation des lois de la maison mère. La cohabitation entre territorialité et extraterritorialité des lois peut donner lieu soit à des conflits soit à des situations de fraude. En l’absence de coopération entre Etats, les succursales qui sont des formes de rayonnement extérieur de la société deviennent des instruments pour pratiquer non seulement le forum shopping mais aussi le law shopping et le tax shopping. / The branches implanted in foreign countries are more autonomous than branches situated in some country as the parent Company. They evolve in a different legal environment and consequently the links with the parent Company are distended. The Court of the State of reception of the branch is competent and laws of this Country are applicable. But the laws of the host country are not the only ones to be applicable. The cohabitation between territoriality and extraterritoriality of the laws can give rise either to conflicts or the situations of fraud. In the absence of cooperation between States the branches witch are forms of brilliance exterior of the Company are transformed into instruments to have a practice not only forum shopping but also law shopping and tax shopping.

On étudie les fonctions multivaluées vers un espace de Hilbert. Après avoir introduit unebonne notion de p énergie, on donne une définition possible d’espace de Sobolev et on prouveun théorème d’existence des p minimiseurs. Puis on considère les fonctions bivaluées de deuxvariables, stationnaires pour les déformations au départ et à l’arrivée. On démontre qu’ellessont localement lipschitziennes et on utilise cette régularité pour montrer la convergence fortedans W1,2 vers leur unique éclatement en un point. L’ensemble de branchement d’une tellefonction est la réunion localement finie de courbes analytiques qui se rencontrent en faisantdes angles égaux. Nous donnons aussi un exemple de fonction discontinue et stationnaireseulement pour les déformations au départ.Dans un deuxième temps, on prouve qu’il n’existe pas de rétraction uniformément continuede l’espace des champs vectoriels continus vers le sous-espace de ceux dont la divergence estnulle en un sens distributionnel. On généralise ce résultat en toute codimension en utilisant lanotion de m charge et à tout ensemble X ⊂ Rn vérifiant une hypothèse géométrique mineure. / We study multiple valued functions with values in a Hilbert space. We introduce a possibledefinition of Sobolev spaces and the rightful notion of p energy. We prove the existence of pminimizers. Then we consider two-valued real functions of two variables which are stationarywith respect to both domain and range transformations. We prove their local Lipschitzcontinuity and use it to establish strong convergence in W1,2 to their unique blow-up at anypoint. We claim that the branch set of any such function consists of finitely many real analyticcurves meeting at nod points with equal angles. We also provide an example showing thatstationarity with respect to domain transformations only does not imply continuity.In a second part, we prove that there does not exist a uniformly continuous retractionfrom the space of continuous vector fields onto the subspace of vector fields whose divergencevanishes in the distributional sense. We then generalise this result using the concept of mcharges on any subset X _ Rn satisfying a mild geometric condition, there is no uniformlycontinuous representation operator for mcharges in X.

The aim of this thesis is to present the top management of 3M Czech Republic with a comprehensive solution to their CSR implementation task. The thesis starts by giving the reader an insight into the today's forms of business ownership including corporations and by covering the issue of governance explains why corporations need a solution like CSR. Subsequently, the theoretical foundations of CSR are presented, followed by an explanation of the actual business tool. Additionally, a generic implementation roadmap is devised together with key success factors of this process identified. Based on this generic roadmap, a tailored solution for 3M Czech Republic including specific recommendations on measures and key performance indicators is developed.

Asymptotic Giant Branch (AGB) stars are stars with low- to intermediate mass in a late stage in their stellar evolution. An important feature of stellar evolution is the ongoing nucleosynthesis, the creation of heavier elements. Unlike main sequence stars, the AGB stars have a thick convective envelope which makes it possible to dredge-up the heavier fused elements from the stellar core to its surface. AGB stars are also pulsating variable stars, meaning the interior expands and contracts, causing the brightness to fluctuate. These pulsations will also play a major role in the mass loss observed in these stars. The mass loss is caused by stellar winds that accelerate gas and dust from the surface of these stars and thereby chemical enrich the interstellar medium. It is important to understand the properties of these pulsations since they play a key role in how stellar winds are produced and then enrich the galaxy with heavier synthesized elements. These pulsation periods can be observed with their corresponding Light-Curves, where the periodic motion of the brightness can be clearly seen. The main goal with this project is to calculate these pulsation periods for different AGB stars and compare these values with the periods listed in the General Catalogue of Variable Stars (GCVS). The comparison between these values gives a better understanding of methods of determining these periods and the uncertainties that follow. / Asymptotiska jättegrenen är en del av slutstadiet för låg- till medelmassiva stjärnor (AGB stjärnor). Ett viktigt kännetecken hos stjärnutvecklingen är den pågående nukleosyntesen, sammanslagningen av tyngre ämnen i stjärnans inre. Till skillnad mot stjärnor på huvudserien har AGB stjärnor ett tjockt konvektivt lager som gör det möjligt att dra upp dessa nybildade ämnen till stjärnans yta. AGB stjärnor är pulserande variabla stjärnor där variationer i stjärnans radie gör att ljusstyrkan varierar. Dessa pulsationer kommer även att spela en viktig roll för den massförlust som observeras hos dessa stjärnor. Massförlusten orsakas av stjärnvindar som accelererar gas och stoft från stjärnans yta och därmed kemiskt berikar det interstellära mediet. Det är viktigt att förstå dessa pulsationer eftersom de är en viktig komponent för hur stjärnvindar uppstår och sedan berikar galaxer med tyngre ämnen. Dessa pulsationsperioder kan studeras genom att observera stjärnornas ljuskurvor, där man tydligt ser det periodiska beteendet hos ljusstyrkan. Det huvudsakliga målet med detta projekt är att beräkna dessa perioder för olika AGB stjärnor och att sedan jämföra dem med värden från General Catalogue of Variable Stars (GCVS). Jämförelsen mellan dessa värden ger en bättre förståelse för metoderna som används för att bestämma dessa perioder och hur osäkra dessa värden är.

Thesis advisor: Philip G. Altbach / Thesis advisor: Karen D. Arnold / Over 200 international branch campuses (IBCs) currently exist globally and the number continues to rise (Lawton & Katsomitros, 2012). This study examines the strategy, structure, and motivation behind a single American IBC--Texas A&M University at Qatar (TAMUQ). Drawing from organizational theory and international higher education literature, this research reveals important considerations for institutions developing or currently operating IBCs. Findings stemmed from 27 in-depth qualitative interviews with faculty and administrators from the branch campus in Qatar, the main campus in Texas, and the host country sponsor. Multiple factors contributed to Texas A&M being poised and ready to accept the opportunity to open an international branch campus: an invitation from a host country sponsor willing to cover all expenses, existing international ambitions, and strong support from the central administration. The inception period leading up to the opening of the branch campus proved crucial for success. University administrators wisely developed buy-in among campus constituencies, negotiated important contract stipulations with the host country, ensured that the institution's existing structure could reasonably support such an endeavor, and assessed whether Qatar was a good fit. The early years of TAMUQ resembled a startup organization. The pioneering team of faculty and staff brought an entrepreneurial spirit necessary to build the institution, but they operated largely independent from the home campus in Texas. A later push for greater ties with the main campus was difficult but important for progress. Since TAMUQ is a derivative of the main campus, administrators had to consider the degree to which they would replicate and adapt various institutional elements. Academically, the curriculum is only modified slightly, but course content and pedagogy are adapted more heavily in response to the unique needs of the student population. Hiring faculty with experience teaching on the main campus is considered an important way to maintain quality, yet administrators consistently struggle to recruit faculty. Unlike other IBCs, TAMUQ has developed a robust research program through the financial support of the host country sponsor. / Thesis (PhD) — Boston College, 2014. / Submitted to: Boston College. Lynch School of Education. / Discipline: Educational Leadership and Higher Education.