This study examines the significance of quality when included in the specification of a hospital cost function. Also, this research estimates a value for scale economies in order to determine if the average hospital experiences increasing returns to scale in the production of hospital care, verifying such findings in previous econometric studies. Furthermore, two functional forms are compared: the Cobb-Douglas and the translog. The results of this study demonstrate that quality has a significant impact on costs. This relationship is positive meaning increasing quality will also increase the cost of producing hospital care. The results for scale economies demonstrate that the average hospital experiences increasing returns to scale in the production of hospital care, which is consistent with previous research. Lastly, based on an F-test, this study is able to accept the translog as the appropriate functional form. / Master of Arts

Στην παρούσα εργασία ασχοληθήκαμε με την εκτίμηση συναρτήσεων κόστους επένδυσης για εργοστάσια παραγωγής ενέργειας από βιοαέριο στην Ευρώπη καθώς και με τη συνοπτική παρουσίαση της τεχνολογίας βιοαερίου. / In the present paper cost functions for biogas energy plants in Europe are estimated. Additionaly biogas technologies are briefly presented in order for the Greek investors to be familiarised with the advantages of using biogas.

The logging industry of the Amazon is a topic that has received little attention in the literature, beyond specific single firm case studies. This has not allowed estimation of cost and production functions that can be used to predict changes in the industry in response to external market factors or government policies. Cost functions and rents are very important to characterize the dynamics of industry behavior, as well as providing important information for future policies. This study relies on a survey of 527 firms to estimate harvest, transportation, and milling cost functions for the logging industry in the Brazilian Amazon, finding variables such as labor cost, distance from the forest to the sawmill, equipment and frontier type to significantly affect the total and marginal cost of each activity. Rents are also estimated for different sampled milling centers, and a cost minimizing mathematical programming model is presented that explains the advance of the logging frontier in Brazil. / Master of Science

We present a utility accrual real-time scheduling algorithm called CIC-VCUA, for tasks whose execution times are functions of their starting times. We model such variable execution times employing variable cost functions (or VCFs). The algorithm considers application activities that are subject to time/utility function time constraints (or TUFs), execution times described using VCFs, and concurrent, mutually exclusive sharing of non-CPU resources. We consider the multi-criteria scheduling objective of (1) assuring that the maximum interval between any two consecutive, successful completions of jobs of a task must not exceed a specified upper bound, and (2) maximizing the system's total accrued utility, while satisfying mutual exclusion resource constraints. Since the scheduling problem is intractable, CIC-VCUA statically computes worst-case sojourn times of tasks, selects tasks for execution based on their potential utility density, and completes them at specific times, in polynomial-time. We establish that CIC-VCUA achieves optimal timeliness during under-loads. Further, we identify the conditions under which timeliness assurances hold. Our simulation experiments illustrate CIC-VCUA's effectiveness and superiority. / Master of Science

Cost automata are traditional finite state automata enriched with a finite set of counters that can be manipulated on each transition. Based on the evolution of counter values, a cost automaton defines a function from the set of structures under consideration to the natural numbers extended with infinity, modulo a boundedness relation that ignores exact values but preserves boundedness properties. Historically, variants of cost automata have been used to solve problems in language theory such as the star height problem. They also have a rich theory in their own right as part of the theory of regular cost functions, which was introduced by Colcombet as an extension to the theory of regular languages. It subsumes the classical theory since a language can be associated with the function that maps every structure in the language to 0 and everything else to infinity; it is a strict extension since cost functions can count some behaviour within the input. Regular cost functions have been previously studied over finite words and trees. This thesis extends the theory to infinite trees, where classical parity automata are enriched with a finite set of counters. Weak cost automata, which have priorities {0,1} or {1,2} and an additional restriction on the structure of the transition function, are shown to be equivalent to a weak cost monadic logic. A new notion of quasi-weak cost automata is also studied and shown to arise naturally in this cost setting. Moreover, a decision procedure is given to determine whether or not functions definable using weak or quasi-weak cost automata are equivalent up to the boundedness relation, which also proves the decidability of the weak cost monadic logic over infinite trees. The semantics of these cost automata over infinite trees are defined in terms of cost-parity games which are two-player infinite games where one player seeks to minimize the counter values and satisfy the parity condition, and the other player seeks to maximize the counter values or sabotage the parity condition. The main contributions and key technical results involve proving that certain cost-parity games admit positional or finite-memory strategies. These results also help settle the decidability of some special cases of long-standing open problems in the classical theory. In particular, it is shown that it is decidable whether a regular language of infinite trees is recognizable using a nondeterministic co-Büchi automaton. Likewise, given a Büchi or co-Büchi automaton as input, it is decidable whether or not there is a weak automaton recognizing the same language.

This study presents a conceptual design process for one-way reinforced concrete slabs cast over Textile Reinforced Concrete (TRC) Stay-in-Place (SiP) formwork elements, aiming at the minimization of the composite slab cost satisfying Ultimate Limit State (ULS) and Serviceability Limit State (SLS) design criteria. The thin-walled TRC element is considered to participate in the structural behaviour of the composite slab. This distinct function of the TRC element (as formwork and as a part of a composite element) distinguishes the design procedure into two States: a Temporary and a Permanent one. Design parameters such as the type of the textile reinforcement (material), the geometry of the TRC cross-section, the flexural strength of the fine-grained concrete in the TRC element and the compressive strength of the cast in-situ concrete are considered as the main optimization variables.

In this thesis I offer new results on how we can acquire, reward, and use accurate predictions of future events. Some of these results are entirely theoretical, improving our understanding of strictly proper scoring rules (Chapter 3), and expanding strict properness to include cost functions (Chapter 4). Others are more practical, like developing a practical cost function for the [0, 1] interval (Chapter 5), exploring how to design simple and informative prediction markets (Chapter 6), and using predictions to make decisions (Chapter 7). / Engineering and Applied Sciences

This thesis is devoted to the development of extensions of dynamic programming to the study of decision trees. The considered extensions allow us to make multi-stage optimization of decision trees relative to a sequence of cost functions, to count the number of optimal trees, and to study relationships: cost vs cost and cost vs uncertainty for decision trees by construction of the set of Pareto-optimal points for the corresponding bi-criteria optimization problem. The applications include study of totally optimal (simultaneously optimal relative to a number of cost functions) decision trees for Boolean functions, improvement of bounds on complexity of decision trees for diagnosis of circuits, study of time and memory trade-off for corner point detection, study of decision rules derived from decision trees, creation of new procedure (multi-pruning) for construction of classifiers, and comparison of heuristics for decision tree construction. Part of these extensions (multi-stage optimization) was generalized to well-known combinatorial optimization problems: matrix chain multiplication, binary search trees, global sequence alignment, and optimal paths in directed graphs.

This study presents a conceptual design process for one-way reinforced concrete slabs cast over Textile Reinforced Concrete (TRC) Stay-in-Place (SiP) formwork elements, aiming at the minimization of the composite slab cost satisfying Ultimate Limit State (ULS) and Serviceability Limit State (SLS) design criteria. The thin-walled TRC element is considered to participate in the structural behaviour of the composite slab. This distinct function of the TRC element (as formwork and as a part of a composite element) distinguishes the design procedure into two States: a Temporary and a Permanent one. Design parameters such as the type of the textile reinforcement (material), the geometry of the TRC cross-section, the flexural strength of the fine-grained concrete in the TRC element and the compressive strength of the cast in-situ concrete are considered as the main optimization variables.

Embedded real time applications are often subject to time and energy constraints. Real time applications are usually characterized by logically separable set of tasks with precedence constraints. The computational effort behind each of the task in the system is responsible for a physical functionality of the embedded system. In this work we mainly define theoretical models for relating the quality of the physical func- tionality to the computational load of the tasks and develop optimization problems to maximize the quality of the system subject to various constraints like time and energy. Specifically, the novelties in this work are three fold. This work deals with maximizing the final output quality of a set of precedence constrained tasks whose quality can be expressed with appropriate cost functions. We have developed heuristic scheduling algorithms for maximizing the quality of final output of embedded applications. This work also dealswith the fact that the quality of output of a task in the system has noticeable effect on quality of output of the other dependent tasks in the system. Finally run time characteristics of the tasks are also modeled by simulating a distribution of run times for the tasks, which provides for averaged quality of output for the system rather than un-sampled quality based on arbitrary run times. Many real-time tasks fall into the IRIS (Increased Reward with Increased Service) category. Such tasks can be prematurely terminated at the cost of poorer quality output. In this work, we study the scheduling of IRIS tasks on multiprocessors. IRIS tasks may be dependent, with one task feeding other tasks in a Task Precedence Graph (TPG). Task output quality depends on the quality of the input data as well as on the execution time that is allowed. We study the allocation/scheduling of IRIS TPGs on multiprocessors to maximize output quality. The heuristics developed can effectively reclaim resources when tasks finish earlier than their estimated worst-case execution time. Dynamic voltage scaling is used to manage energy consumption and keep it within specified bounds.