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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
511

Uma comparação entre a PPP e o enfoque da produtividade na taxa de câmbio de longo prazo

Rebelo, Helene Albuquerque 23 October 2014 (has links)
Made available in DSpace on 2016-03-15T19:26:16Z (GMT). No. of bitstreams: 1 Helene Albuquerque Rebelo 1.pdf: 1046658 bytes, checksum: 341e6608b9c7f265ac5e1303f07c7667 (MD5) Previous issue date: 2014-10-23 / Fundo Mackenzie de Pesquisa / The dissertation examines the behavior of the exchange rate in the long term from the perspective of the classical model of purchasing power parity theory (PPP), developed empirically by Cassel and the alternative model proposed by Basso originating from the Marxist benchmark, which emphasizes prices and productivities to determine the exchange rate. The exchange rate behavior is examined for three countries over the 1977-2006 period, with annual frequency. To test the models, it was used the consumer price index (CPI), the GDP, the value-added price index and gross producer price index (EU KLEMS database). The essay uses the causality tests of Johansen, the Dickey-Fuller and Phillips-Perron unit root tests, the VAR (vector autoregression) and VEC (vector error correction) models and performing a projection with the Model Confidence Set. It is ascertained that PPP was not supported for any of the 12 models generated. In Basso s approach, the 48 models generated, cointegration was found in only four models, therefore it is not possible to generalize the new model. / A dissertação examina o comportamento da taxa de câmbio no longo prazo sobre a perspectiva do modelo clássico da paridade do poder de compra (PPC) ou purchasing power parity theory (PPP), desenvolvido empiricamente por Cassel e do modelo alternativo proposto por Basso oriundo do referencial marxista, enfatizando preços e produtividades para determinar a taxa de câmbio. Examina-se o comportamento da taxa de câmbio para três países no período de 1977 a 2006, com frequência anual. Para testar os modelos, foram empregados o índice de preço ao consumidor (IPC), o deflator do PIB, o deflator dos valores agregados e o deflator de produção total (base de dados EU KLEMS). O trabalho utiliza o teste de causalidade de Johansen, os testes de raiz unitária de Dickey e Fuller e Phillips-Perron, os modelos de VAR (vetores autorregressivos) e VEC (vetores autorregressivos com correção de erro) e é feito projeção com Model Confidence Set. Constata-se que a PPP não foi corroborada para nenhum dos 12 modelos gerados. Na abordagem de Basso, dos 48 modelos gerados, encontrou-se cointegração apenas em quatro, portanto, não é possível generalizar o novo modelo.
512

Implementation and Performance Comparison of Some Heuristic Algorithms for Block Sorting

Turlapaty, Sandhya 01 January 2018 (has links)
An implementation framework has been developed in this thesis for a well-known APX-hard combinatorial optimization problem known as Block Sorting. The motivation for the study of this problem comes from applications such as computational biology and optical character recognition. While existing Block Sorting research has been theoretically focused on the development and analysis of several approximation algorithms for Block Sorting, little or no work has been carried out thus far on the implementation of the proposed approximation algorithms. The conceptualization of an implementation framework and illustrating its use by experimenting with the existing approximation algorithms will provide means for discovering newer approaches to handling this important problem. As the main contribution, the research in this thesis provides a new greedy algorithm for Block Sorting in which each block move either reduces the number of blocks by two or three blocks, or reduces by one the number of reversals or inversions in the orig- inal permutation. Experimental results for all algorithms are also provided along with a comparison of their performance using the number of block moves and approximation ratios as performance metrics when sorting permutations of a given order, and as the order of permutations is varied. Preliminary results from the experimentation were shared at the 2017 IEEE 17th International Conference on Bioinformatics and Bioengineering (BIBE) [1]. To the best of our knowledge, this is the first work that has been focused on the implementation and experimental performance analysis of any algorithm for Block Sorting. We believe the results presented in this thesis will be useful for researchers and practitioners working in this area.
513

A holistic approach to green networking in wireless networks : collaboration among autonomic systems as a mean towards efficient resource-sharing / Une approche holistique pour les réseaux sans fil économes en énergie

Peres, Martin 19 December 2014 (has links)
Les vingt dernières années ont vu l’émergence de systèmes sans fil dans la vie de tous les jours. Ils ont rendu possible la création de technologies telles que les téléphones portables, le WiFi ou l’internet mobile qui sont maintenant tenus pour acquis dans la société actuelle. L’impact environnemental des technologies de l’information et des communications connaît une croissance exponentielle et a atteint l’impact de l’industrie du transport aérien. L’initiative d’informatique verte a été lancée en réponse à cette observation pour réduire de 15 à 30% les émissions de gaz à effet de serre en 2020 comparé aux prédictions faites en 2002 afin de garder le réchauffement climatique inférieur à 2°C. Dans cette thèse, nous avons étudié des techniques d’économie d’énergie dans les réseaux sans fil et comment elles interagissent entre elles afin de donner une vue holistique des réseaux verts. Nous prenons également en compte l’usage du spectre radio fréquence qui est le moyen le plus utilisé pour les communications entre systèmes sans fil et qui devient une ressource rare à cause du besoin grandissant de notre société pour de la bande passante en mobilité. Cette thèse suit les couches réseaux avant de remonter les piles matérielleset logicielles. Des contributions ont été apportées à la plupart des couches afin de proposer un réseau sans fil autonome où les noeuds peuvent collaborer pour améliorer les performances du réseau, réduire de façon globale l’utilisation du spectre radio tout en limitant la consommation énergétique du réseau. / The last twenty years saw the emergence of wireless systems in everyday’s life. They made possible technologies such as mobile phones, WiFi or mobile Internet which are now taken for granted in today’s society. The environmental impact of Information and Communications Technology (ICT) has been raising exponentially to equate the impact of the airline industry. The green computing initiative has been created in response to this observation in order to meet the 15%-30% reduction in green-house gases by 2020 compared to estimations made in 2002 to keep the global temperature increasebelow 2°C. In this thesis, we studied power-saving techniques in wireless networks and how they interact with each others to provide a holistic view of green networking. We also take into account the radio frequency resource which is the most commonly usedcommunication medium for wireless systems and is becoming a scarce resource due to our society’s ever-increasing need for mobile bandwidth. This thesis goes down the network stacks before going up the hardware and software stack. Contributions have been madeat most layers in order to propose an autonomic wireless network where nodes can work collaboratively to improve the network’s performance, globally reduce the radio frequency spectrum usage while also increasing their battery life.
514

反向策略投資台灣股市之可行性研究 / The feasibility of contrarian in Taiwan stock market

謝佳如, Shieh, Jia-Ru Unknown Date (has links)
在國內外實證文獻中,已有許多學者研究市場過度反應的現象,但由採取的研究方法不盡相同,故結論也有所差異.本研究是希望能對台灣股市的個別股票報酬率作一較完整的檢視,先瞭解股票報酬率前後期的相關情形,試圖找出一些一致性,再提出股市交易的策略,並比較策略的獲利性。 將樣本分成對稱與不對稱的形成期及檢定期,採Spearman等級相關係數法先對台灣股市同一股票的報酬率在不同期間(形成期及檢定期)的表現是否有相關作一檢視,接著檢定此相關係數時間序列是否具有隨機的特質,而後將證券交易稅及手續費納入考慮後,比較三種投資策略-買入持有輸家、中間、贏家的獲利性、風險及績效表現。 本文的實證結果:由單位風險報酬率來看,投資股市應以買入有長期的策略才會有較好的績效表現,而買入持有短期的績效是最差的。以不同的樣本期間討論台灣股市是否有價格反彈,結果並不相同。在1980年-1998年的Spearman等級相關係數多為正值,表示市場在288天以下多沒有價格反彈,且以連檢定的結果多為顯著,以Jensen α檢定之,贏家投資策略能獲得超額報酬。在1990年-1998年不論是重覆取樣、未重覆取樣,Spearman等級相關係數,多為負值,表示市場應存有價格反彈的現象,且以連檢定的結果多為顯著,但以Jensen α檢定之,輸家卻無法獲得超額報酬。可能是因為考慮了交易稅與手續費,而影響了投資策略的獲利性。 / There have been many articles discussing overreaction. Because of the difference of methods and samples, the conclusions are different. This thesis tries to make a more complete examination of Taiwan Stock Market. We divide sample period to be formation period and test period which are symmetric and asymmetric. Besides that, we adopt overlapping and nonoverlapping sampling. The sample period is 1980 January 1 to 1998 January 22. Three investment strategies are buying and holding loser portfolio、middle portfolio and winner portfolio. We use Spearman rank correlation to discuss whether the return of Taiwan Stock Market has correlation between formation period and test period. Then we adopt one of nonparameter statitics analysis-run test to examine whether the time series of Spearman rank correlation is a random walk. Following are our summaries: 1.The longer period we hold the stock,the better return we acquire. 2.In the first sample (1980 Jan 1 to 1998 Jan 22), Spearman rank correlation. is almost positive, and the hypothesis of run test is significant. We imply buying and holding the winner portfolio is the best strategy. We can prove this by using Jense α. In this case, buying and holding winner can get excess return. 3.In the second sample(1990 Nov 1 to 1998 Jan 22), Spearman rank correlaion is almost negative, and the hypothesis of run test is signficant. We imply buying and holding the loser portfolio is the best strategy. But we can not prove the by using Jense α. As we can not acqure excess return by buying and holding loser portfolio.
515

Evaluation of infiltration, run-off and sediment mobilisation using rainfall simulations in the Riebeek-Kasteel Area, Western Cape - South Africa

Joseph Twahirwa January 2010 (has links)
<p>The project was conducted on a small-scale catchment at Goedertrou in the Riebeek- Kasteel district. The focus of this study was to address some of the hydrological processes active in the research catchment, namely infiltration, run-off and sediment mobilisation on different soil types. It was done to investigate the origin of Berg River pollutants. To answer the overall question about what influence the natural salt load of the Berg River, a number of subprojects have been identified, one of which is to understand the hydrological processes in the soil mantle and vadose zone. Hence, the study aimed to answer the research questions mentioned and discussed in section 1.3 of Chapter 1. Considering the results, it could be suggested that decayed root systems from the rows of plants, soil cracks, small channels and openings created by small animals, as well as slope orientation and, therefore, soil composition, all played a major role in influencing the ability of the soil to absorb the simulated rainfall. In this study, the factors that influenced run-off are micro topography, soil moisture, root system, animal activities in soil profile, soil crack dimensions and the hydraulic conductivity. The main factors that played a major role to influence sediments mobilisation are strongly believed to be the micro topography within the ring, slope gradient and length, vegetation cover and rainfall-simulation intensity. After using different techniques, the results show that farmers must be aware that with storm rainfall, particles smaller than 65 &mu / m are subject to mobilisation. It is important to let land-users know that they need proper and appropriate methods for land-use.</p>
516

Movilización de metales pesados en residuos y suelos industriales afectados por la hidrometalurgia del cinc.

Solano Marín, Antonia Mª 19 December 2005 (has links)
Entre las actividades potencialmente contaminantes del suelo se encuentra la industria de obtención de cinc, que, a lo largo de la historia, ha generado cantidades importantes de residuos con elevados contenidos de metales pesados depositados en las inmediaciones de sus instalaciones hasta épocas recientes. Después de la promulgación del RD 9/2005, dicha contaminación y el riesgo que conlleva deberán ser evaluados en los diferentes emplazamientos. El objetivo de esta tesis es el estudio de la movilización natural y forzada de plomo, cadmio y arsénico bajo distintas condiciones medioambientales en residuos procedentes de la hidrometalurgia del cinc y en suelos industriales contaminados por los productos de alteración de dichos residuos, así como la relación que existe entre la movilización y las características químicas y mineralógicas de los mismos, ya que el conocimiento de estos materiales y de las condiciones de movilización de los metales estudiados puede ayudar al estudio metodológico de evaluación de la contaminación así como al análisis de riesgos que permita la toma de decisiones ante la posible recuperación de tales terrenos. / Among the industries that mar be considered potential contaminators of the soil is that dedicated to obtaining zinc, which, during its time, has generated substantial quantities ofheavy metal-containing wastes which, until recently, were simply dumped in the irnmediate environs. Following the Spanish law RD 9/2005, the resulting contamination and any associated risks have to be evaluated. The object ofthis thesis was to study the natural and forced mobilization oflead, cadmium and arsenic in a variety of environmental conditions in wastes resulting from the zinc hydrometallurgy indus1ry and in soils contaminated by fue alteration products of these wastes, together with fue relation between such mobilization and fue chemical and mineralogical characteristics of the same. Knowledge of these material s and of the metal mobilization conditions studied will help in the methodological study of contamination evaluation and in the analysis of risks. The findings will, it is hoped, help in the making decisions that need to be taken to recover the affected soils.
517

Hur korrelerar GIH:s Pyramidtest med VO2max på rullband för elitorienterare?

Edlund, Elin, Wiik, Robert January 2011 (has links)
Syfte och frågeställningar Syftet med studien var att undersöka för elitorienterare resultaten vid och korrelationen mellan ett så kallat 5 minuters pyramidtest (5MPT) och ett maximalt test för bestämning av maximalt syreupptag (VO2max) på rullband. Frågorna vi ställde oss var: Vilken korrelation föreligger mellan 5MPT och ett bestämt VO2max på rullband hos elitorienterare? Hur ser en jämförelse ut mellan uppmätt samt beräknat VO2max? Vilken är reliabiliteten för 5MPT? Hur ser ekvationen ut för att beskriva sambandet mellan dessa två olika maxtester? Metod I valideringsstudien deltog 16 elitorienterare (6 kvinnor och 10 män) i åldrarna 17 till 37 år. De två testerna som genomfördes var 5MPT och bestämning av VO2max på rullband. 5MPT är ett skytteltest som är fem minuter långt, där testpersonen (tp) tar sig fram och tillbaka mellan två stolpar (sträcka 5.5 m) där en vertikal trappa (formad likt en pyramid) passeras under varje vända. Antalet vändor, skattad ansträngning samt hjärtfrekvens (HF) registrerades. Utvecklad power (effekt) erhölls genom produkten av vikt, gravitation, antal vändor, höjd på högsta plinten (0,62 m) dividerat med total duration i 5MPT. Testet för att bestämma VO2max utfördes med löpning på ett motordrivet rullband. Under den första minuten av testet sprang tp på en hastighet av 8km/h (kvinnor) respektive10km/h (män) utan lutning. För varje minut ökades hastigheten med 1km/h. Lutningen höjdes med en grad efter minut ett och därefter med 0,5 grader/minut. Testet pågick till dess tp nått sin VO2max. Var 15:e sekund registrerades tp:s HF, VO2 (l/min), VCO2 (l/min), VO2 (ml/kg/min) och respiratorisk kvot (RER) med hjälp av ett datoriserat syreupptagningssystem. Resultat Korrelationen var signifikant och hög (r = 0,89, p&lt;0,0001) mellan utvecklad power på 5MPT och VO2max (l/min) och även mellan antalet vändor på 5MPT och VO2max (l/min) (r = 0,89, p&lt;0,0001) på detta material av elitorienterare. Följande formler, baserade på resultaten från elitorienterarna, kan användas för att predicera VO2max efter genomfört 5MPT: VO2max  (l/min) = (5MPTPOWER – 50,914) / 25,795 VO2max (l/min) = (5MPTVÄNDOR – 74,447) / 9,7668 Slutsats 5MPT uppvisar en stark korrelation med bestämd VO2max sett till power och/eller antalet genomförda vändor. Beräkningsformler för prediktion av VO2max har varit möjligt att beskriva. Se resultatdelen för andra resultat och samband mellan 5MPT och VO2max. / Abstract Aim The aim of this study was to investigate for elite orienteers the results in and the correlation between a so called 5-minutes-pyramid test (5MPT) and a specific maximum oxygen uptake test (VO2max) on a treadmill. The questions we asked ourselves were: Which correlation exists between 5MPT and a specific VO2max on the treadmill for elite orienteers? How would a comparison look like between measured and estimated VO2max? What is the reliability for the 5MPT? How would an equation look like that describe the correlation above? Method In the validity the study 16 elite orienteers (6 women and 10 men) aged 17 to 37 years participated. The two tests that have been carried out were the 5MPT and determined VO2max during running on a treadmill. The 5MPT is a 5-minute-shuttle test, in which the participant moves back and forth in a short interval (5.5 m) over boxes (highest height: 0.62) formed like a pyramid. Power in the pyramid test (5MPTPOWER) was calculated as the product of numbers of laps, body weight, gravity and highest box level divided by time. To determine VO2max the method running on a treadmill was performed. During the first minute the running speed was 8km/h (women)/10 km/h (men) without elevation. Each minute the velocity increased with 1 km/h. The elevation increased with 1 degree after the first minute and thereafter with 0,5 degrees/minute.  The test was finished when the participant had reached her VO2max. Every 15 second the participants heart rate, VO2 (l/min), VCO2 (l/min), VO2 (ml/kg/min) and RER, was registered by means of an online system. Results The correlation between the developed power of the 5MPT and measured VO2max (l/min) was high (r = 0.89, p&lt;0,0001) and also between the number of laps in the 5MPT and measured VO2max (l/min) (r = 0.89, p &lt; 0,0001). The following formulas can be used to predict VO2max after completed 5MPT: VO2max  (l/min) = (5MPTPOWER – 50,914) / 25,795 VO2max (l/min) = (5MPTLAPS – 74,447) / 9,7668 Conclusions 5MPT show a strong correlation with VO2max determined in terms of power and/or the number of completed laps. Calculated formulas for prediction of VO2max have been possible to describe. See results section for other results and relationships between 5MPT and VO2max. / Maximal Aerobic Power versus Performance in Two Aerobic Endurance Tests among Young and Old Adults.Andersson E, Lundahl N, Wecke L, Lindblom I, Nilsson, J.
518

"What Are Marines For?" The United States Marine Corps in the Civil War Era

Krivdo, Michael Edward 2011 May 1900 (has links)
This dissertation provides analysis on several areas of study related to the history of the United States Marine Corps in the Civil War Era. One element scrutinizes the efforts of Commandant Archibald Henderson to transform the Corps into a more nimble and professional organization. Henderson's initiatives are placed within the framework of the several fundamental changes that the U.S. Navy was undergoing as it worked to experiment with, acquire, and incorporate new naval technologies into its own operational concept. Analysis of the strengths and weaknesses of Henderson's programs are provided and comparisons drawn with those priorities established by his successor, Commandant John Harris. In addition, the operations undertaken by the Corps during the Civil War are evaluated in terms of their relative benefit for the national military establishment as a whole. The Corps organization and operational concept is scrutinized and compared with that of similar military structures. In particular, the relationship between the U.S. Marine Corps and the Confederate States Marine Corps are compared. In the process, the South's Corps, born in part out of that of the North's, exhibited many distinct advantages that the USMC solidly resisted adopting during the war years. The influence of key leaders, both military and civilian, reveals many problems that continued to negatively affect the Corps' ability to meet operational requirements as defined by senior naval and Army commanders. Yet despite these issues, the Corps' Civil War experiences served as a crucible for forging a new generation of leaders who earnestly fought for reforms and increased professionalization of the unit. Although the Corps suffered from several problems related to lack of institutional vision and leadership failings of some senior officers, at a small unit level the officers and Marines performed their duties in a competent, enthusiastic, and courageous manner. Therefore, Marines continued to be in great demand by naval commanders at all levels, who actively sought their service in a variety of operation.
519

Model-Based Run-time Verification of Software Components by Integrating OCL into Treaty / Modellbasierte Verifikation von Softwarekomponenten zur Laufzeit am Beispiel der Treaty-OCL-Integration.

Wilke, Claas 22 April 2010 (has links) (PDF)
Model Driven Development is used to improve software quality and efficiency by automatically transforming abstract and formal models into software implementations. This is particularly sensible if the model’s integrity can be proven formally and is preserved during the model’s transformation. A standard to specify software model integrity is the Object Constraint Language (OCL). Another topic of research is the dynamic development of software components, enabling software system composition at component run-time. As a consequence, the system’s verification must be realized during system run-time (and not during transformation or compile time). Many established verification techniques cannot be used for run-time verification. A method to enable model-based run-time verification will be developed during this work. How OCL constraints can be transformed into executable software artifacts and how they can be used in the component-based system Treaty will be the major task of this diploma thesis. / Modellgetriebene Entwicklung dient der Verbesserung von Qualität und Effizienz in der Software-Entwicklung durch Automatisierung der notwendigen Transformationen von abstrakten bzw. formalen Modellen bis zur Implementierung. Dies ist insbesondere dann sinnvoll, wenn die Integrität der ursprünglichen Modelle formal bewiesen werden kann und durch die Transformation gewährleistet wird. Ein Standard zur Spezifikation der Integrität von Softwaremodellen ist die Object Constraint Language (OCL). Eine weitere Forschungsrichtung im Software-Engineering ist die Entwicklung von dynamischen Komponenten-Modellen, die die Komposition von Softwaresystemen im laufenden Betrieb ermöglichen. Dies bedeutet, dass die Systemverifikation im laufenden Betrieb realisiert werden muss. Die meisten der etablierten Verifikationstechniken sind dazu nicht geeignet. In der Diplomarbeit soll ausgehend von diesem Stand der Technik eine Methode zur modellbasierten Verifikation zur Laufzeit entwickelt werden. Insbesondere soll untersucht werden, wie OCL-Constraints zur Laufzeit in ausführbare Software-Artefakte übersetzt und in dem komponentenbasierten System Treaty verwendet werden können.
520

CUSUM tests based on grouped observations

Eger, Karl-Heinz, Tsoy, Evgeni Borisovich 08 November 2009 (has links) (PDF)
This paper deals with CUSUM tests based on grouped or classified observations. The computation of average run length is reduced to that of solving of a system of simultaneous linear equations. Moreover a corresponding approximation based on the Wald approximations for characteristics of sequential likelihood ratio tests is presented. The effect of grouping is investigated with a CUSUM test for the mean of a normal distribution based on F-optimal grouping schemes. The considered example demonstrates that hight efficient CUSUM tests can be obtained for F-optimal grouping schemes already with a small number of groups.

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