本文將設定一 Translog 多產品成本函數模型，以估計台灣旅行業之規模 經濟 (Economies of Scale) 及多樣化經濟 (Economies of Scope)程度 。在 Translog 多產品成本函數模型中，係以廠商所經營之四項業務，包 括來華觀光、出國旅遊、國民旅遊及代辦業務等，當作四種不同的產品， 而要素投入則為勞動與資本租賃。實證結果顯示，台灣旅行業普遍存在規 模經濟的現象。此結果可能導致：第一，所謂``靠行''的形成；第二，規 模較小的廠商可能根據本身的競爭優勢與經營特色而採取市場區隔化策略 ，以服務某特定之顧客群；第三，現有旅行業廠商之間的合併，或是來自 產業外的廠商藉購併進入旅行業市場，以從事多角化經營。另外，就產品 生產效率而言，我們以多樣化經濟存在與否認為，來華觀光與出國觀光之 間、來華觀光與國民旅遊之間，以及出國觀光與國民旅遊之間，因其業務 關聯性不大，而無法發揮資源共用共享的效果，因此不適合聯合生產。而 出國觀光與代辦業務之間，因業務關聯性大，因此若能聯合生產，則必然 能夠產生綜效。至於來華觀光與代辦業務之間，以及國民旅遊與代辦業務 之間，雖無明顯之證據顯示其具有聯合生產之優勢，但若存在閒置產能， 或是因某種業務之專業性不高，致使人力資源之轉換成本不大時，亦不排 除聯合生產之可能。

<p>In this dissertation I study substantially the effects of disembodied technical change on the total factor productivity and inputs demand in U.S. Apparel industry during 1958-1996. A time series input-output data set over the sector employs to estimate an error corrected model of a four-factor transcendental logarithmic cost function. The empirical results indicate technical impact on the total factor productivity at the rate of 9% on average. Technical progress has in addition a biased effect on factor augmenting in the sector.</p>

In this dissertation I study substantially the effects of disembodied technical change on the total factor productivity and inputs demand in U.S. Apparel industry during 1958-1996. A time series input-output data set over the sector employs to estimate an error corrected model of a four-factor transcendental logarithmic cost function. The empirical results indicate technical impact on the total factor productivity at the rate of 9% on average. Technical progress has in addition a biased effect on factor augmenting in the sector.

The main area of emphasis in this study is to investigate the methods and technology for aerodynamic configuration sizing of missiles and to develop a software platform in MATLAB&reg / environment as a design tool which has an ability of optimizing the external configuration of missiles for a set of flight requirements specified by the user through a graphical user interface. A genetic algorithm based optimization tool is prepared by MATLAB is expected to help the designer to find out the best external geometry candidates in the conceptual design stage. Missile DATCOM software package is employed to predict the aerodynamic coefficients needed in finding the performance merits of a missile for each external geometry candidate by integrating its dynamic equations of motion. Numerous external geometry candidates are rapidly eliminated according to objectives and constraints specified by designers, which provide necessary information in preliminary design. In this elimination, the external geometry candidates are graded according to their flight performances in order to discover an optimum solution. In the conceptual design, the most important performance objectives related to the external geometry of a missile are range, speed, maneuverability, and control effectiveness. These objectives are directly related to the equations of motion of the missile, concluding that the speed and flight range are related to the total mass and the drag-to-lift ratio acting on missile. Also, maneuverability depends on the normal force acting on missile body and mass whereas the control effectiveness is affected by pitching moment and mass moment of inertia of missile. All of the flight performance data are obtained by running a two degree-of-freedom simulation. In order to solve the resulting multi-objective optimization problem with a set of constraint of linear and nonlinear nature and in equality and inequality forms, genetic-algorithm-based methods are applied. Hybrid encoding methods in which the integer configuration variables (i.e., nose shape and control type) and real-valued geometrical dimension (i.e., diameter, length) parameters are encoded in the same individual chromosome. An external configuration design tool (EXCON) is developed as a synthesis and external sizing tool for the subsonic cruise missiles. A graphical user interface (GUI), a flight simulator and optimization modules are embedded into the tool. A numerical example, the re-configuration problem of an anti-ship cruise missile Harpoon, is presented to demonstrate the accuracy and feasibility of the conceptual design tool. The optimum external geometries found for different penalty weights of penalty terms in the cost function are compared according to their constraint violations and launch mass values. By means of using EXCON, the launch mass original baseline Harpoon is reduced by approximately 30% without deteriorating the other flight performance characteristics of the original Harpoon.

Σκοπός της εργασίας αυτής είναι η τεχνοοικονομική σύγκριση των δυο αρχιτεκτονικών, ADSL και οπτικών δικτύων και η εξαγωγή συμπερασμάτων για τα σχετικά κόστη και δυνατότητες που αφορούν τις αρχιτεκτονικές αυτές. Οι τελευταίες τεχνολογίες καθώς και οι αυξημένες απαιτήσεις σε χωρητικότητα και ταχύτητα, οδήγησαν σε λύσεις που συνδυάζουν διαφορετικά είδη τεχνολογιών, κυρίως υβριδικές τεχνολογίες, που προσφέρουν τεράστιες δυνατότητες με περιορισμένο κόστος ανά bit. Για τις απαιτήσεις της εποχής η τεχνολογία FTTx (Fiber To The x) και οι διάφορες παραλλαγές της, αποτελούν πολύ υποσχόμενες τεχνολογίες πρόσβασης που προσφέρονται ως βάσεις για τη δημιουργία μεγάλων και αξιόπιστων δικτύων που μπορούν να εξυπηρετήσουν μεγάλο αριθμό πελατών. Ωστόσο, οι πλέον υποσχόμενες τεχνολογίες είναι οι τεχνολογίες FTTx, οι οποίες υλοποιούνται αποκλειστικά με οπτικές ίνες. Όπως θα δούμε σε ήδη υπαρκτά δίκτυα, τα δίκτυα αναμορφώνονται και εξελίσσονται από παλαιότερες τεχνολογίες, αναβαθμίζονται σταδιακά, χωρίς να σημαίνει ότι οι παλαιότερη τεχνολογία μένει σε αχρηστία αμέσως μετά τις αναβαθμίσεις. Γίνονται αναφορές σε περιπτωσιολογικές μελέτες που πρέπει να γίνουν ώστε να είναι όσο το δυνατό πιο εύχρηστο και προσπελάσιμο ένα δίκτυο ενός μητροπολιτικού κέντρου. Η εργασία αυτή ολοκληρώνεται με συναρτήσεις κόστους, για την ολοκλήρωση ενός τέτοιου δικτύου, που εξάγονται υλοποιούνται με χρήση του εργαλείου Matlab. / The primary objective of this work is the techno economic comparison between ADSL and optic fiber networks, the export of conclusions on the relative costs and the capabilities that concern these architectures. The secondary objective is understanding the process of constructing an optical fiber nework. The latest technologic improvements as well as the increased requirements in speed and capacity, lead to solutions that combine different technologies types mainly hybrid technologies, which offer enormous possibilities with limited cost per bit. For present day requirements FTTx (Fiber the The x) can serve a large share of customers as base for creating bigger and more reliable networks. However, this promising technology is exclusively for only optical fiber based FTTx. As it will be shown through examples of already founded networks, they can be reformed and evolved from older technologies, can be progressively upgraded to mach the bandwidth and user capacity of future networks Case studies are performed in order to determine the best case of optical network that should satisfy consumers and telecommuters. This thesis is completed with the research of total cost functions which are imported in Matlab. The cost reports are exported and compared in the form of graphic cost charts.

The EU has been promoting unbundling of the transmission grid from other stages of the electricity supply chain with the aim of fostering competition in the upstream stage of electricity generation. At presence, ownership unbundling is the predominant form of unbundling in Europe. However, the benefits of increased competition from ownership unbundling of the transmission grid may come at the cost of lost vertical synergies between the formerly integrated stages of electricity supply. The policy debate generally neglects such potential costs of unbundling, yet concentrates on its benefits. Therefore European cross-country evidence may shed some light on this issue. This study helps fill this void by empirically estimating the magnitude of economies of vertical integration (EVI) between electricity generation and transmission based on a quadratic cost function. For this purpose we employ novel firm-level panel data of major European electricity utilities. Our results confirm the presence of substantial EVI, which put the policy measure of transmission ownership unbundling into question. (authors' abstract) / Series: Department of Economics Working Paper Series

Submitted by Marilene Donadel (marilene.donadel@unioeste.br) on 2018-10-23T17:20:41Z No. of bitstreams: 1 Wagner_Franca_2018.pdf: 1672761 bytes, checksum: cbabb751327c3b80926b9fbde714a9e3 (MD5) / Made available in DSpace on 2018-10-23T17:20:41Z (GMT). No. of bitstreams: 1 Wagner_Franca_2018.pdf: 1672761 bytes, checksum: cbabb751327c3b80926b9fbde714a9e3 (MD5) Previous issue date: 2018-05-14 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / The global primary energy mix is mostly composed by nonrenewable resources and the use of which uses contributes to increase the greenhouse gas emissions. The consumption of oil and coal, responsible for attending 60% of the total energy demand between 1970 and 2015, is more likely to enhance the air pollution than the consumption of natural gas. Besides, some authors announce the impossibility of sustaining the demand of oil with conventional type only at around 2050, because of technical and economic constraints over the reserves. Technology has been playing a roll giving more flexibility to the interfuel substitution among fossil fuels, in many applications. That gives the opportunity to increase the share of natural gas in the primary mix, while reducing the consumptions of the other two. Moreover, the reserves of natural gas are larger in comparison with the ones of oil, allowing it to alleviate the pressure over the latter. From those perspectives, increasing the use of natural gas would contribute to reduce the negative environment externality and the extension of a possible shock to be unleashed in the energy supply. The objective of this dissertation is to seek for a substitutability between natural gas and the others fossil fuels in the primary energy demand, using the Morishima Elasticity of Substitution, between 1970 and 2015. The model started with a Translog cost function to obtain the input demand equations of each fuel and their cost share functions, applying Shephard’s lemma. The parameters of the econometric regression were estimated by the Seemingly Unrelated Regressions method, as means to measure the price elasticity, the Allen Elasticity of Substitution and the Morishima Elasticity of Substitution. The model was applied to the United States due to their significance in the global context of energy. The results showed that a single conclusion for the period as a whole is statistically insignificant. Based on own-price elasticities, there were clearly three structural brakes, statistically significant, which divided the time series in four intervals. In the interval 1970-1981, the natural gas had a complementary relation with oil and both were substitutes for coal. In the intervals 1982-1995 and 1996-2008, there was substitutability among natural gas and oil, although limited. In the most recent interval, all of the fuels were complements to each other. Putting together the elasticities of substitution and the price elasticities analysis, we conclude that factors exogenous to the free market relations, such as government interventions, were determinants to demand decisions. The lack of a continuous and consistent relation of substitution between natural gas and the other two fossil fuels, warns that the concerns presented in this work may have being neglected and a transition from a polluted and finite mix to another cleaner and renewable, bridged by natural gas, is not occurring in the world’s largest economy. / A matriz mundial de energia primária é composta predominantemente por recursos não renováveis e cujo consumo contribui para a intensificação do efeito estufa. O consumo do petróleo e do carvão, combustíveis que supriram mais de 60% da demanda total de energia entre 1970 e 2015, é mais intensivo na geração de poluentes do que o consumo do gás natural. Além disso, alguns autores datam para próximo de 2050 a impossibilidade de sustentar a demanda de petróleo, pelo esgotamento técnico e econômico das reservas do tipo convencional. A tecnologia vem dando flexibilidade para que haja a substituição dentre os combustíveis fósseis, em várias aplicações. Isso gera a oportunidade de aumentar o consumo do menos poluidor, o gás natural, em substituição aos outros dois. O gás natural também possui reservas relativamente maiores do que as do petróleo, o que permite a ele aliviar parte da pressão colocada sobre este último. Por estas perspectivas, aumentar a participação do gás natural contribui para a mitigação da externalidade ambiental e reduz a magnitude de uma possível crise causada por um choque de oferta. O objetivo geral desta dissertação é responder se há uma relação de substituição entre o gás natural e os outros combustíveis fósseis na demanda de energia primária, pela Elasticidade de Substituição de Morishima, no período entre 1970 e 2015. O modelo partiu de uma função de custos do tipo Translog para chegar às equações de demanda condicionada de cada combustível e às equações de participação de custo, aplicando o lema de Shepard. Os parâmetros da regressão econométrica foram estimados pelo método Seemingly Unrelated Regressions e usados para os cálculos das elasticidades da demanda aos preços, de substituição de Allen e de substituição de Morishima. O modelo foi aplicado aos Estados Unidos, dada a significância deste país no contexto mundial de energia. Os resultados mostraram que uma única conclusão para todo o período é estatisticamente insignificante. Com base nas elasticidades aos próprios preços, foi possível identificar três quebras estruturais, estatisticamente significativas, dividindo o período em quatro intervalos. No intervalo 1970-1981, o gás natural se mostrou complementar ao petróleo e, estes dois, substitutos ao carvão. Nos intervalos 1982-1995 e 1996-2008 foi identificada uma relação de substituibilidade entre o gás natural e o petróleo, apesar de limitada. No mais recente, todos os combustíveis tiveram relações de complementariedade. Aliando estas às interpretações das elasticidades-preço, concluiu-se que fatores externos ao mercado, como interferências de governo, foram mais determinantes para as decisões de demanda. Não ter sido possível encontrar uma relação de substituição entre o gás natural e os outros dois fósseis, de forma contínua e consistente, deixa o alerta de que as preocupações levantadas podem estar sendo negligenciadas e que a transição de uma matriz predominantemente suja e finita para outra mais limpa e renovável, mediada pelo gás natural, não está em curso na maior economia do mundo.

No description available.

There has been a huge surge in the Internet of Things (IoT) applications in recent years. The sensor nodes in the IoT network generate data continuously that directly affects the longevity of the network. Even though the potential of IoT applications are immense, there are numerous challenges like security, privacy, load balancing, storage, heterogeneity of devices, and energy optimization that have to be addressed. Of those, the energy utilization of the network is of importance and has to be optimized. Several factors like residual energy, temperature, the load of Cluster Head (CH), number of alive nodes, and cost function affect the energy consumption of sensor nodes. In this paper, a hybrid Whale Optimization Algorithm-Moth Flame Optimization (MFO) is designed to select optimal CH, which in turn optimizes the aforementioned factors. The performance of the proposed work is then evaluated with existing algorithms with respect to the energy-specific factors. The results obtained prove that the proposed method outperforms existing approaches.

Integrating sophisticated statistical methods into database management systems is gaining more and more attention in research and industry. One important statistical method is time series forecasting, which is crucial for decision management in many domains. In this context, previous work addressed the processing of ad-hoc and recurring forecast queries. In contrast, we focus on subscription-based forecast queries that arise when an application (subscriber) continuously requires forecast values for further processing. Forecast queries exhibit the unique characteristic that the underlying forecast model is updated with each new actual value and better forecast values might be available. However, (re-)sending new forecast values to the subscriber for every new value is infeasible because this can cause significant overhead at the subscriber side. The subscriber therefore wishes to be notified only when forecast values have changed relevant to the application. In this paper, we reduce the costs of the subscriber by optimizing the notifications sent to the subscriber, i.e., by balancing the number of notifications and the notification length. We introduce a generic cost model to capture arbitrary subscriber cost functions and discuss different optimization approaches that reduce the subscriber costs while ensuring constrained forecast values deviations. Our experimental evaluation on real datasets shows the validity of our approach with low computational costs.