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An 18-month study (July 2009 – December 2010) was conducted to determine the influence of four dams located in series along the Perak River, in Malaysia: Temengor, Bersia, Kenering and Chenderoh dams. The framework for investigation centered around the Serial Discontinuity Concept (SDC) and the Cascading Reservoir Continuum Concept (CRCC). In addition to reservoir, tailwater and riverine reach characteristics, the interacting influences of tributary streams and watersheds were addressed. Variables included in-situ environmental physical parameters, nutrients, seston concentration and transport, and fish assemblage characteristics. In-situ variables, water and seston samples, were recorded/collected monthly from all four reservoirs, their associated riverine sections, and their primary tributaries. Fish samples were collected by using experimental gill nets in reservoirs. Fish were enumerated taxonomically and total length and weight were measured for the bony-lipped barb, Osteochilus hasselti (Valenciennes, 1842). Hypotheses were tested using analyses of variance with permutations. Relationships were determined using correlation, and multivariate and regression analyses. The integrated influences of discontinuity and cascading on nutrient and seston transport dynamics and fish assemblages (except for relative condition and biomass of O. hasselti) were operative in dynamic juxtaposition along the river’s continuum, and depended on distance between dams and presence and size of tributary streams. However, principal tributaries along the four serial dams in the Perak River appeared to have little spatial influence on their respective system’s nutrient and seston dynamics due to dilution effects of mainstem discharges. Among all tributaries, only the Rui River depicted reversal of the serial discontinuity trend in its system. Even so, its influence on its system was limited. Effects of ecosystem fragmentation along the river’s continuum on in-situ, nutrients and seston transport dynamics, and fish assemblages existed, but not necessarily in line with the SDC nor in line with the CRCC. The dynamics of in-situ, nutrient, seston and fish assemblage parameters were more associated with land use, reservoir surface area and dam discharge. Results from this study generated a hypothesis that submerged woody vegetation in the reservoirs may augment and compensate lost nutrients, thereby minimizing functional impacts of serially-arranged dams.

A new approach to the evaluation of the reliability of electrical systems is presented. In this approach a Graph Trace Analysis based approach is applied to integrated system models and reliability analysis. The analysis zones are extended from the traditional power system functional zones. The systems are modeled using containers with iterators, where the iterators manage graph edges and are used to process through the topology of the graph. The analysis provides a means of computationally handling dependent outages and cascading failures. The effects of adverse weather, time-varying loads, equipment age, installation environment, operation conditions are considered. Sequential Monte Carlo simulation is used to evaluate the reliability changes for different system configurations, including distributed generation and transmission lines. Historical weather records and loading are used to update the component failure rates on-the-fly. Simulation results are compared against historical reliability field measurements. Given a large and complex plant to operate, a real-time understanding of the networks and their situational reliability is important to operational decision support. This dissertation also introduces using an Integrated System Model in helping operators to minimize real-time problems. A real-time simulation architecture is described, which predicts where problems may occur, how serious they may be, and what is the possible root cause. / Ph. D.

In 1998 the UN Guiding Principles on Internal Displacement were developed following years of crises faced by the millions of people experiencing forced displacement, especially those internally displaced. These Principles were widely considered to be precedent setting, both historically and normatively. However, the examination of the construction of the international norms that underpin the Principles indicates that there are important epistemological weaknesses in widely used constructivist frameworks that understand normative shifts in international relations. They are critiqued as being impedingly linear, temporally compressed and analytically obstructive in its agent-centric view of norm cascading. This research aims to address some of these gaps with an enhanced life-cycle model using cluster genealogies and the processes of replication and particularization. The reformulated framework is tested for robustness and feasibility using two preliminary cases – UNSC Resolution 1325 and the Chemical Weapons Convention. It is then used to conduct an in-depth original analysis of the development of the 1998 UN Guiding Principles. The findings in the case of the Guiding Principles show, for example, that though the acceptance of the IDP definition was a big leap, the replication and particularization of human rights limits the humanitarian scope of the Guiding Principles, and also brings into question existing humanitarian protection of IDPs under the Geneva Conventions. Meanwhile, rooting them in ‘sovereignty as responsibility’ has not shifted the community of states’ intersubjective take on sovereignty, but it has added to the existing normative tension – individual vs. state – that underpins the very understanding of sovereignty.

Substations are joints in the power system that represent nodes that are vital to stable and reliable operation of the power system. They contrast the rest of the power system in that they are a dense combination of critical components causing all of them to be simultaneously vulnerable to one isolated incident: weather, attack, or other common failure modes. Undoubtedly, the loss of these vital links will have a severe impact to the to the power grid to varying degrees. This work creates a cascading model based on protection system misoperations to estimate system risk from loss-of-substation events in order to assess each substation's criticality. A continuation power flow method is utilized for estimating voltage collapse during cascades. Transient stability is included through the use of a supervised machine learning algorithm called random forests. These forests allow for fast, robust and accurate prediction of transient stability during loss-of-substation initiated cascades. Substation risk indices are incorporated into a preventative optimal power flow (OPF) to reduce the risk of critical substations. This risk-based dispatch represents an easily scalable, robust algorithm for reducing risk associated with substation losses. This new dispatch allows operators to operate at a higher cost operating point for short periods in which substations may likely be lost, such as large weather events, likely attacks, etc. and significantly reduce system risk associated with those losses. System risk is then studied considering the interaction of a power grid utility trying to protect their critical substations under a constrained budget and a potential attacker with insider information on critical substations. This is studied under a zero-sum game theoretic framework in which the utility is trying to confuse the attacker. A model is then developed to analyze how a utility may create a robust strategy of protection that cannot be heavily exploited while taking advantage of any mistakes potential attackers may make. / Ph. D.

Esta dissertação de mestrado investiga os formatos de modulação óptica alternativos ao tradicional formato binário de intensidade (NRZ - Non-return-to-zero), ditos avançados, como tecnologia chave para atender às exigências do mercado atual de telecomunicações por transporte de grande volume de dados e alta largura de banda, associados com a redução do custo da informação transmitida por bit. Os formatos avançados de modulação óptica fazem parte das tecnologias que estão sendo investigadas intensamente com o objetivo de superar os desafios impostos pela nova geração de sistemas ópticos com taxas a partir de 40 Gb/s. Este trabalho focaliza o estudo dessa tecnologia, apresentando uma visão geral dos formatos mais discutidos atualmente, suas características e tecnologias de implementação. Foram realizadas simulações utilizando o software comercial Optisystem versão 7.0 da empresa canadense Optiwave Systems Inc., para analisar o desempenho de alguns formatos de modulação de intensidade e de fase com respeito à sensibilidade do receptor, resistência ao cascateamento de filtragem óptica e a efeitos dispersivos e não-lineares. Procurou-se avaliar os formatos em enlaces reais, com características necessárias à sua possível utilização. Também é feita uma breve consideração dos custos associados aos formatos de modulação analisados neste trabalho. Dentre os formatos analisados, os RZ (Return-to zero) apresentaram maior sensibilidade do receptor e melhor tolerância aos efeitos não-lineares que os seus equivalentes NRZ, porém baixa tolerância aos efeitos dispersivos e ao cascateamento de filtragem óptica. O formato duobinário mostrou fraco desempenho de sensibilidade, mas provou ser o mais tolerante à dispersão cromática e à concatenação de filtragem óptica. Os formatos de modulação de fase mostraram ser bem resistentes aos efeitos não-lineares e aos efeitos dispersivos. / This MSc thesis investigates optical modulation formats as an alternative to the use of the traditional intensity binary format NRZ (Non-return-to-zero). Those formats, classified as advanced, represent one of the key technologies aimed to enable the high data volume and broadband, demanded by the present telecommunication market, with cost reduction of transmitted information per bit. Those technologies have been intensevely studied with purpose of overcoming the challenges imposed by the new generation of optical systems, with bit rates from 40 Gb/s. This work focuses on the study of modulation formats most discussed currently, presenting an overview of their main characteristics and implementation techniques. The performance of some intensity and phase formats, in terms of receiver sensitivity, optical filtering cascading, dispersion and nonlinear effects robustness, have been theoretically analyzed from simulations carried out with the commercial software Optisystem v. 7.0, of the Canadian company Optiwave Systems Inc. The analysis has been applied to real optical links, with characteristics that, potentially, demand their use. A cost analysis, based on estimated values associated to devices required for implementing the formats investigated in this work, is also presented. Among the formats studied, those based on RZ (Return-to zero) presented the highest receiver sensitivity and best tolerance to nonlinear effects, in comparison to their equivalent formats, based on NRZ. However, they are less tolerant to dispersive effects and optical filtering cascading. The duobinary format (DB) has shown a weak performance in terms of sensitivity, though has been proved to be the most tolerant to chromatic dispersion and filtering cascading effects. Among all formats, the phase modulation ones presented the highest resistance against nonlinear and dispersive effects.

於歷史事件中我們知道電力網路中些許的傷害會導致大停電事件的發生，而電力網路的安全是學者們一直以來關心的議題，複雜網路發展至今，已有不少研究人員利用複雜網路的方法來分析電力網路，本論文即利用複雜網路的分析方法，分析台灣電力網路脆弱性，並提出一新穎的保護策略。 文章中引用三種分析方法分析台灣電力網路的脆弱性，第一為根據網路效率(efficiency of complex network)，第二為根據靜態負載的連鎖性失效(static load cascading failure)，第三為根據動態負載的連鎖性失效(dynamic load cascading failure)，三種脆弱性分析的方法得到結果的交集處，在文中被認為是電力網路中最具風險的變電站。根據靜態負載的連鎖性失效的結果，我們在不改變網路結構和整體網路的負載量之下，提出一新穎的安全策略，試圖降低靜態負載時連鎖性失效帶來的傷害，並分析此安全策應用至ER隨機網路(ER random network)、BA無尺度網路(BA scale-free network)和台灣電力網路，且量化其結果。 三種脆弱分析的結果皆有共通的部份，表示台灣電力網路在拓樸分析下並不堅固，其結果顯示此安全策略是有效的。本篇論文分析的網路均是無權重也無方向性的網路，如此，未來在網路脆弱性與安全策略的研究還有進一步的研究空間。 / From blackout events in history, we know the damage of a few substations or transmission lines can lead to a big blackout, and the robustness of power grids are always a great concern. Recently the topological analyses of power grid network have developed rapidly and its achievements have become a center of attention. This thesis aims to investigate the vulnerability of Taiwan’s power grid through topological analyses and propose a novel protection strategy. This thesis introduces three methods to investigate the vulnerability of Taiwan’s power grid. The first method is based on efficiency of complex network. The second method is based on static load cascading failure. The third method is based on dynamic load cascading failure. The common results of the three results are considered the high risks in Taiwan’s power grid. According to the static load cascading failure, we propose a protection strategy against cascading failure without changing the structure of network and the whole load of the network, and then demonstrate the effectiveness of this strategy on an ER random network, a BA scale-free network and Taiwan’s power grid numerically. The three methods having the common results, one may say Taiwan’s power grid isn’t robust under the topological analyses, and our protection strategy may be useful for decreasing the damage after cascading failure.

現實社會中，有時會發生大規模的停電事件，一經調查後才瞭解，只是因為一根電纜線、一根高壓電塔或是一個變電站故障導致，令人好奇電力系統的運作模式。因此藉由拓蹼網路的特性去研究電力系統的安全性及穩定性，一直受到人們的關注和討論。本篇論文利用動態負載去模擬現實中的電流，並藉由連鎖性失效的攻擊策略對於網路效率的影響，去判斷其網路的脆弱性分析。 本論文利用網路效率的(efficiency)影響來作為網路脆弱性(vulnerability)的分析，藉由在靜態負載中連鎖性失效的模型(static load cascading failure model)和動態負載中連鎖性失效的模型(dynamic load cascading failure model)來判斷及討論，其中動態負載為不同發電量及消耗量的狀況，藉此觀察台灣的電力網路系統在狀況下的結果。 此外以攻擊方來思考，單一攻擊、多重攻擊和策略性的多重攻擊的狀況底下，網路效率的變化，並將此運用在台灣電力網路系統上，發現台灣電力網路相當脆弱。 / In the real world, sometimes there will be black out (power shortage) happening in large scale areas. After investigating, we found out that it was cause by either a broken transmission line, a high-voltage tower or a substation. We are very interesting to know how the operation scheme of power system works. Therefore, we study the safety and the stability in power system by the characteristics of topology network. This subject is always concerned and discussed by the society. The thesis use dynamic load to simulate current in real world. We foc us effect on network efficiency by the strategy of cascading failure, analyze the vulnerability of network. The thesis use the variation of network efficiency as index to analyze network. According to determining and discussing by static load cascading failure model and dynamic load cascading failure model, dynamic load is the situation in different amount of generating and consumption of electrical energy. We used the data to observe the result of Taiwan power system under the situation. In addition to, changing of internet efficiency by single attack, multi-attack and strategic multi-attack in attacker method of thinking. We found that Taiwan power system is weak after we used the statistics on it.

這篇論文主要可以分成兩個部分。第一部分，我們整理了關於複雜網路的初步研討。最重要的特性有：小世界網路、無尺度度分布。並且介紹了三種模型：BA 模型、EBA模型，以及W-S small world model。接著對於一份實際的社會網路資料—台灣業餘桌球選手對戰網路，做網路的結構分析，試驗其是否具有上述的兩種特性。透過兩種可以模擬出無尺度度分布特性的模型：BA以及EBA模型。我們藉由這兩種模型模擬的結果，以及和競賽網路的比較，試者去闡述模型與理論間為何有些相似，卻又如此不同。並討論了賽制設計對於結構的影響。 在第二部分裡，我們回顧了一些對於網路的拓樸性效率以及可靠度效率的研討，並且討論了兩種不同負載定義下的連鎖故障行為。最後我們使用其中三種方法：拓樸性效率脆弱性、參與中間度(betweenness)過載引發的連鎖性故障行為，以及電力網路的動態電流變化造成的連鎖性故障，對於一個假想的電網做傳輸線的弱點排序。其中由動態電流過載(transient dynamic overload)造成的連鎖性故障可以視為一個簡化後的電力動態網路模型，藉由這三者間排序的不同，我們可以看到複雜網路分析以及基於電力網路傳輸特性所模擬的結果差異。 / This thesis can be divided into two parts. In the first part, we review some basic properties of the complex networks. The most important features are: small world networks and scale-free degree distribution. Then, we introduce three complex models : BA model, EBA model, and W-S small world model. Next, we analyze a real data—CTTC network to test if it has the features we have mentioned above. By the EBA and BA model simulations, we try to illustrate why there are some similarities between the simulations and real data, but they are still so different in most of aspects. In the second part, we review the definitions of the topology and reliable efficiency of a network structure. Next, we discuss two cascading failure model based on different definitions of load of a transmission line in a power grid. Finally, we use three different ways: topology efficiency vulnerability, cascading failure triggered by betweenness overload, and cascading failure triggered by the transient dynamics overload to test the vulnerability of edges in an assuming power grid. The cascading failure triggered by the transient dynamic overload can be viewed as a simplified power flow model. We sort the most vulnerable edges in three different ways. By this, we can observe the difference of the vulnerability analysis based on the complex network and the characteristic of the power transmission..

Submitted by Alexandra Cisotto Belline (alexandrabelline@yahoo.com.br) on 2016-06-14T19:42:18Z No. of bitstreams: 1 Dissertação Alexandra Versão Entregue 14 06 2016.pdf: 8341218 bytes, checksum: 387a098a147e1b777b282c181b5bbe1c (MD5) / Rejected by Joana Martorini (joana.martorini@fgv.br), reason: Seu trabalho foi rejeitado devendo fazer alterações on 2016-06-14T20:01:27Z (GMT) / Submitted by Alexandra Cisotto Belline (alexandrabelline@yahoo.com.br) on 2016-06-15T19:08:39Z No. of bitstreams: 1 Dissertação Alexandra Versão Entregue 14 06 2016.pdf: 8341218 bytes, checksum: 387a098a147e1b777b282c181b5bbe1c (MD5) / Rejected by Joana Martorini (joana.martorini@fgv.br), reason: Trabalho rejeitado. on 2016-06-15T19:24:58Z (GMT) / Submitted by Alexandra Cisotto Belline (alexandrabelline@yahoo.com.br) on 2016-06-15T21:22:31Z No. of bitstreams: 1 Dissertação Alexandra Versão Entregue 15 06 2016.pdf: 8349846 bytes, checksum: 06c7baecfb96c1fde4d0888192b79639 (MD5) / Rejected by Renata de Souza Nascimento (renata.souza@fgv.br), reason: Trabalho rejeitado. Arrumar a numeração das páginas, conforme informado por telefone. Att. on 2016-06-15T21:51:14Z (GMT) / Submitted by Alexandra Cisotto Belline (alexandrabelline@yahoo.com.br) on 2016-06-15T22:46:58Z No. of bitstreams: 1 Dissertação Alexandra Versão Entregue 15 06 2016 V2.pdf: 8347795 bytes, checksum: 78b9bb6d1a74cee3c4b50a58f24ea70e (MD5) / Approved for entry into archive by Renata de Souza Nascimento (renata.souza@fgv.br) on 2016-06-15T22:58:02Z (GMT) No. of bitstreams: 1 Dissertação Alexandra Versão Entregue 15 06 2016 V2.pdf: 8347795 bytes, checksum: 78b9bb6d1a74cee3c4b50a58f24ea70e (MD5) / Made available in DSpace on 2016-06-16T12:16:07Z (GMT). No. of bitstreams: 1 Dissertação Alexandra Versão Entregue 15 06 2016 V2.pdf: 8347795 bytes, checksum: 78b9bb6d1a74cee3c4b50a58f24ea70e (MD5) Previous issue date: 2016-05-09 / Since the mid-1990s the Brazilian business environment has experienced a significant increase in the sophistication of modeling corporate structures for large enterprises, a type of knowledge, however, mostly restricted to participants in these ventures and its legal and financial counsel. In the case of the corporate structure of Brazil Telecom, however, it was possible to access all documents and information in order to study this structure, due to the massive litigation involving this company for almost ten years , where most part of the documents analyzed in this dissertation were found. This material is precious because the case of Brazil Telecom - known as one of the major in Brazilian corporate law - has a very important peculiarity: the group was managed by a minority shareholder, Opportunity group, which exercised power control during those ten years, despite its diminished equity interest and strong opposition suffered from major shareholders for most of the time in which that power was exercised. The aim of this study is to reveal the legal techniques that allowed the exercise of this power, as well as to seek to understand why, in spite of so much opposition from other shareholders and the massive litigation, it took years for the Opportunity to be definitely removed from the administration and the exercise of controlling power of Brazil Telecom. / Desde meados dos anos 1990 o ambiente de negócios brasileiro tem passado por um relevante incremento na sofisticação da modelagem de estruturas societárias para grandes empreendimentos, um tipo de conhecimento que, porém, fica na maior parte restrito aos participantes desses empreendimentos e seus assessores jurídicos e financeiros. No caso da estruturação societária da Brasil Telecom, entretanto, foi possível ter acesso a todos os documentos e informações necessários ao estudo dessa estrutura, devido à enorme quantidade de litígios judiciais em que essa companhia esteve envolvida por quase dez anos, nos quais se pode obter a maior parte dos documentos analisados neste trabalho. Esse material é precioso, pois o caso da Brasil Telecom, conhecido como um dos maiores do direito societário brasileiro, tem uma peculiaridade muito importante: o grupo era gerido por um acionista minoritário, o grupo Opportunity, que exerceu poder de controle durante esses dez anos, apesar de sua diminuta participação societária e da forte oposição que sofreu dos acionistas majoritários por quase todo o tempo em que exerceu esse poder. O objetivo desse trabalho é revelar as técnicas jurídicas que permitiram o exercício desse poder, bem como buscar entender por que, apesar de tanta oposição dos demais acionistas e da enorme litigiosidade, anos transcorreram até que o Opportunity fosse definitivamente afastado da administração e do exercício do poder de controle da Brasil Telecom.