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Comparative analysis on approximation algorithms for the resource constrained project scheduling problem

Coelho, José; Valadares, Luis Tavares
Fonte: EURO Working Group on Project Management and Scheduling Publicador: EURO Working Group on Project Management and Scheduling
Tipo: Artigo de Revista Científica
Publicado em /04/2002 ENG
Relevância na Pesquisa
65.79%
Project Management and Scheduling - PMS. Valência, 3-5 Abril de 2002; In Resource Constrained Project Scheduling Problem (RCPSP) exact algorithms can only solve small instances, and several approximation algorithms have been proposed that can solve large instances with a quasi-optimal solution. So far there is no comparative analysis of several algorithms running on the same machine, with equal time limit and large instances; this is our main goal. A new performance indicator is proposed that is not affected by the presence of simple problems in the instance set. The instance set was built by assembling the main sets in the literature and also JobShop and FlowShop instances transformed to RCPSP. In this work 30 meta-heuristics were implemented, obtaining a total of 159.364.665 solutions evaluated of RCPSP.

Modelagem ambiental e análise qualitativa comparativa de políticas de implantação de gás natural veicular em ônibus; Environmental Modelling and Qualitative Comparative Analysis of public policies that implemented compressed natural gas on buses

Brito, Thiago Luis Felipe
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 10/02/2015 PT
Relevância na Pesquisa
65.82%
Esta dissertação desenvolveu duas análises de natureza diferente, mas complementares, uma vez que são unidas por uma mesma questão. Esta questão diz respeito à utilização do gás natural veicular em substituição ao óleo diesel em ônibus urbanos. O autor argumenta que, devido a suas características técnicas, o gás natural pode contribuir para a promoção de um transporte mais sustentável, mesmo que o gás natural seja um combustível igualmente não renovável, como o óleo diesel. Na primeira análise desenvolvida, utiliza-se uma metodologia bottom-up para demonstrar os ganhos ambientais que podem ser alcançados ao se substituir o óleo diesel por gás natural em ônibus urbanos. Adota-se a cidade de São Paulo como estudo de caso. Esses ganhos ambientais manifestam-se tanto na redução das emissões de poluentes locais, como material particulado, monóxido de carbono e óxidos de enxofre, conduzindo a melhoras importantes na qualidade de vida das pessoas que sofrem os efeitos nocivos dessas emissões (usuários ou não do transporte público urbano), como, também, no declínio das emissões de gases de efeito estufa, especialmente o dióxido de carbono, levando a benefícios ambientais globais. Os resultados amparam o uso do gás natural em ônibus como uma estratégia de maior sustentabilidade no plano ambiental. Já...

Comparative analysis of synchronization algorithms based on PLL, RDFT and Kalman Filter

Pádua, M. S.; Deckmann, S. M.; Sperandio, G. S.; Marafão, F. P.; Colón, D.
Fonte: Universidade Estadual Paulista Publicador: Universidade Estadual Paulista
Tipo: Conferência ou Objeto de Conferência Formato: 964-970
ENG
Relevância na Pesquisa
65.79%
This paper discusses the main characteristics and presents a comparative analysis of three synchronization algorithms based respectively, on a Phase-Locked Loop, a Kalman Filter and a Discrete Fourier Transform. It will be described the single and three-phase models of the first two methods and the single-phase model of the third one. Details on how to modify the filtering properties or dynamic response of each algorithm will be discussed in terms of their design parameters. In order to compare the different algorithms, these parameters will be set for maximum filter capability. Then, the dynamic response, during input amplitude and frequency deviations will be observed, as well as during the initialization procedure. So, advantages and disadvantages of all considered algorithms will be discussed. ©2007 IEEE.

Comparative analysis between experimental characterization results and numerical fdtd modeling of self-assembled photonic crystals

Silva, A. O.; Bertholdo, R.; Schiavetto, M. G.; Borges, B. V.; Ribeiro, S. J L; Messaddeq, Y.; Romero, M. A.
Fonte: Universidade Estadual Paulista Publicador: Universidade Estadual Paulista
Tipo: Artigo de Revista Científica Formato: 329-342
ENG
Relevância na Pesquisa
65.79%
This paper presents a comparative analysis between the experimental characterization and the numerical simulation results for a three-dimensional FCC photonic crystal (PhC) based on a self-assembly synthesis of monodispersive latex spheres. Specifically, experimental optical characterization, by means of reflectance measurements under variable angles over the lattice plane family [1,1, 1], are compared to theoretical calculations based on the Finite Di®erence Time Domain (FDTD) method, in order to investigate the correlation between theoretical predictions and experimental data. The goal is to highlight the influence of crystal defects on the achieved performance.

Comparative analysis of current and voltage-controlled photovoltaic Maximum Power Point tracking

De Assis Sobreira, Pedro; Villalva, Marcelo Gradella; Barbosa, Pedro Gomes; Braga, Henrique Antônio Carvalho; Gazoli, Jonas Rafael; Ruppert, Ernesto; Ferreira, André Augusto
Fonte: Universidade Estadual Paulista Publicador: Universidade Estadual Paulista
Tipo: Conferência ou Objeto de Conferência Formato: 858-863
ENG
Relevância na Pesquisa
65.79%
Maximum Power Point tracking (MPPT) in photovoltaic (PV) systems may be achieved by controlling either the voltage or current of the PV device. There is no consensus in the technical literature about how is the best choice. This paper provides a comparative analysis performance among current and voltage control using two different MPPT strategies: the perturb and observe (P&O) and the incremental conductance techniques. © 2011 IEEE.

Comparative analysis of strut-and-tie models using Smooth Evolutionary Structural Optimization

Almeida, Valério S.; Simonetti, Hélio Luiz; Oliveira Neto, Luttgardes de
Fonte: Universidade Estadual Paulista Publicador: Universidade Estadual Paulista
Tipo: Artigo de Revista Científica Formato: 1665-1675
ENG
Relevância na Pesquisa
65.83%
The strut-and-tie models are widely used in certain types of structural elements in reinforced concrete and in regions with complexity of the stress state, called regions D, where the distribution of deformations in the cross section is not linear. This paper introduces a numerical technique to determine the strut-and-tie models using a variant of the classical Evolutionary Structural Optimization, which is called Smooth Evolutionary Structural Optimization. The basic idea of this technique is to identify the numerical flow of stresses generated in the structure, setting out in more technical and rational members of strut-and-tie, and to quantify their value for future structural design. This paper presents an index performance based on the evolutionary topology optimization method for automatically generating optimal strut-and-tie models in reinforced concrete structures with stress constraints. In the proposed approach, the element with the lowest Von Mises stress is calculated for element removal, while a performance index is used to monitor the evolutionary optimization process. Thus, a comparative analysis of the strut-and-tie models for beams is proposed with the presentation of examples from the literature that demonstrates the efficiency of this formulation. © 2013 Elsevier Ltd.

Comparative analysis of multicriteria decision making methods

Mota, Pedro Jorge Gomes
Fonte: Faculdade de Ciências e Tecnologia Publicador: Faculdade de Ciências e Tecnologia
Tipo: Dissertação de Mestrado
Publicado em //2013 ENG
Relevância na Pesquisa
65.86%
Dissertação para obtenção do Grau de Mestre em Engenharia Electrotécnica e de Computadores; The main objective of this dissertation is to perform a Comparative Analysis of different Multicriteria Decision Making Methods applied to real-world problems, in order to produce relevant information to enable the incorporation of those methods on computational platforms. The current document presents a simple case study concerning a decision support application targeted for a real problem regarding retrofitting alternatives of a building with energy efficiency impact. The application process was started with the selection of two Multicriteria Decision Making Methods guided by a preexisting framework, and resulted in the choice of AHP and PROMETHEE II methodologies. These two methods were then combined with three different decision maker profiles (Conservative, Moderate and Aggressive) created by means of risk assessment profiling techniques for portfolio allocation. Afterwards, the chosen decision criteria were disposed in a Risk Pyramid according to their inherent level of risk regarding project evaluation. A match was then performed between the decision maker profiles and each criterion, so as to define a proper set of weights for the decision criteria and preference functions...

Comparative analysis of the primate X-inactivation center region and reconstruction of the ancestral primate XIST locus

Horvath, Julie E.; Sheedy, Christina B.; Merrett, Stephanie L.; Diallo, Abdoulaye Banire; Swofford, David L.; NISC Comparative Sequencing Program, ; Green, Eric D.; Willard, Huntington F.
Fonte: Cold Spring Harbor Laboratory Press Publicador: Cold Spring Harbor Laboratory Press
Tipo: Artigo de Revista Científica
Publicado em /06/2011 EN
Relevância na Pesquisa
55.88%
Here we provide a detailed comparative analysis across the candidate X-Inactivation Center (XIC) region and the XIST locus in the genomes of six primates and three mammalian outgroup species. Since lemurs and other strepsirrhine primates represent the sister lineage to all other primates, this analysis focuses on lemurs to reconstruct the ancestral primate sequences and to gain insight into the evolution of this region and the genes within it. This comparative evolutionary genomics approach reveals significant expansion in genomic size across the XIC region in higher primates, with minimal size alterations across the XIST locus itself. Reconstructed primate ancestral XIC sequences show that the most dramatic changes during the past 80 million years occurred between the ancestral primate and the lineage leading to Old World monkeys. In contrast, the XIST locus compared between human and the primate ancestor does not indicate any dramatic changes to exons or XIST-specific repeats; rather, evolution of this locus reflects small incremental changes in overall sequence identity and short repeat insertions. While this comparative analysis reinforces that the region around XIST has been subject to significant genomic change, even among primates...

Theories of Comparative Analysis

Weld, Daniel S.
Fonte: MIT - Massachusetts Institute of Technology Publicador: MIT - Massachusetts Institute of Technology
Formato: 181 p.; 22159466 bytes; 8248976 bytes; application/postscript; application/pdf
EN_US
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55.94%
Comparative analysis is the problem of predicting how a system will react to perturbations in its parameters, and why. For example, comparative analysis could be asked to explain why the period of an oscillating spring/block system would increase if the mass of the block were larger. This thesis formalizes the task of comparative analysis and presents two solution techniques: differential qualitative (DQ) analysis and exaggeration. Both techniques solve many comparative analysis problems, providing explanations suitable for use by design systems, automated diagnosis, intelligent tutoring systems, and explanation based generalization. This thesis explains the theoretical basis for each technique, describes how they are implemented, and discusses the difference between the two. DQ analysis is sound; it never generates an incorrect answer to a comparative analysis question. Although exaggeration does occasionally produce misleading answers, it solves a larger class of problems than DQ analysis and frequently results in simpler explanations.

Regulatory Frameworks for Water Resources Management : A Comparative Study

Salman, Salman M. A.; Bradlow, Daniel
Fonte: Washington, DC: World Bank Publicador: Washington, DC: World Bank
EN_US
Relevância na Pesquisa
55.83%
Water is a scarce and finite resource with no substitute, and upon which the very existence of life on earth depends. The challenges facing water resources are daunting. The Millennium Development Goals aim, inter alia, at reducing by half, by 2015, the proportion of people without sustainable access to safe drinking water and sanitation. Although progress thus far is not encouraging, it is hoped that necessary actions will be taken to achieve this goal during the remaining period. Such actions include financial, institutional, and legal measures. Indeed, without the appropriate legal framework, the ability of the state to regulate, control, and allocate its water resources is hampered; its role in ensuring their efficient and proper use is hindered; and its right to protect those resources is challenged. This study of the regulatory frameworks for water resources management examines water legislation in sixteen jurisdictions, and highlights, in a comparative manner, the key elements needed for an effective regulatory framework. Chapter 1 traces the relevance and importance assigned to water legislation by the different international conferences and forums...

Population, Energy and Environment Program : Comparative Analysis on the Distribution of Oil Rents

World Bank
Fonte: Washington, DC Publicador: Washington, DC
EN_US
Relevância na Pesquisa
65.81%
The issue of administering the distribution of oil rents is the subject of increased debate among oil companies, civil society, development agencies, and governments, which tacit agreement suggests that regions where oil and gas production takes place, in particular the communities, ought to receive "indemnifications" due to damages, and losses derived from the use of land for oil production operations. Such debate sparked the need for an analysis in the context of the tripartite dialogues of the Population, Energy and Environment Program (PEA), a joint initiative by the Bank, and the Latin American Organization for Energy (OLADE). This study presents PEAs comparative analysis of oil rent distribution in Bolivia, Colombia, Ecuador, and Peru, reviews the collection of rents as it relates to taxation of revenues derived from oil, and gas operations, and, examines the distribution, and disbursement of rents, giving special emphasis on the evaluation of the share of revenues, that could directly benefit the indigenous peoples. Recommendations suggest the development of a tax mechanism that distributes revenues equitably among governments...

Evolution and comparative analysis of the MHC Class III inflammatory region

Deakin, Janine; Papenfuss, Anthony T; Belov, Katherine; Cross, Joe; Coggill, P; Palmer, Sophie; Sims, S; Speed, Terence P; Beck, Stephan; Graves, Jennifer
Fonte: Universidade Nacional da Austrália Publicador: Universidade Nacional da Austrália
Tipo: Journal article; Published Version Formato: 14 pages
Relevância na Pesquisa
55.85%
BACKGROUND: The Major Histocompatibility Complex (MHC) is essential for immune function. Historically, it has been subdivided into three regions (Class I, II, and III), but a cluster of functionally related genes within the Class III region has also been referred to as the Class IV region or "inflammatory region". This group of genes is involved in the inflammatory response, and includes members of the tumour necrosis family. Here we report the sequencing, annotation and comparative analysis of a tammar wallaby BAC containing the inflammatory region. We also discuss the extent of sequence conservation across the entire region and identify elements conserved in evolution. RESULTS: Fourteen Class III genes from the tammar wallaby inflammatory region were characterised and compared to their orthologues in other vertebrates. The organisation and sequence of genes in the inflammatory region of both the wallaby and South American opossum are highly conserved compared to known genes from eutherian ("placental") mammals. Some minor differences separate the two marsupial species. Eight genes within the inflammatory region have remained tightly clustered for at least 360 million years, predating the divergence of the amphibian lineage. Analysis of sequence conservation identified 354 elements that are conserved. These range in size from 7 to 431 bases and cover 15.6% of the inflammatory region...

An example of qualitative comparative analysis in nursing research

Donnelly, F.; Wiechula, R.
Fonte: RCN Publishing Co Publicador: RCN Publishing Co
Tipo: Artigo de Revista Científica
Publicado em //2013 EN
Relevância na Pesquisa
65.83%
AIM To describe an example of qualitative comparative analysis (QCA) in a study about the role of clinical placement, nursing education and patient outcomes. BACKGROUND Clinical placement is often considered an essential aspect of nursing education and an invaluable way to prepare students for the reality of nursing. However, many questions about the role of clinical placement remain unanswered, such as duration, style and learning outcomes. QCA is a novel approach to data analysis, which has been used for some time in social science research, and may be useful in tackling such questions. DATA SOURCES Participants (n=16) involved in a case study using questionnaire, in-depth interview and document analysis. REVIEW METHODS Few examples of QCA exist in nursing-related research. Examination of approaches to social sciences and educational research, and the conditions that influence nursing education and clinical placement were conducted via a number of online database searches. DISCUSSION The paper presents an example of how QCA was used to consider whether there is any causal relationship between certain features of clinical placement, such as duration, level of preparation, level of benefit, and the capacity of recently graduated registered nurses to provide a range of nursing interventions for pneumonia...

A comparative analysis reveals weak relationships between ecological factors and beta diversity of stream insect metacommunities at two spatial levels

Heino, Jani; Melo, Adriano S.; Bini, Luis Mauricio; Altermatt, Florian; Al-Shami, Salman A.; Angeler, David G.; Bonada, Nuria; Brand, Cecilia; Callisto, Marcos; Cottenie, Karl; Dangles, Olivier; Dudgeon, David; Encalada, Andrea; Goethe, Emma; Groenroos, M
Fonte: Wiley-Blackwell Publicador: Wiley-Blackwell
Tipo: Artigo de Revista Científica Formato: 1235-1248
ENG
Relevância na Pesquisa
65.81%
Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq); Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES); Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP); Processo FAPESP: 2013/50424-1; The hypotheses that beta diversity should increase with decreasing latitude and increase with spatial extent of a region have rarely been tested based on a comparative analysis of multiple datasets, and no such study has focused on stream insects. We first assessed how well variability in beta diversity of stream insect metacommunities is predicted by insect group, latitude, spatial extent, altitudinal range, and dataset properties across multiple drainage basins throughout the world. Second, we assessed the relative roles of environmental and spatial factors in driving variation in assemblage composition within each drainage basin. Our analyses were based on a dataset of 95 stream insect metacommunities from 31 drainage basins distributed around the world. We used dissimilarity-based indices to quantify beta diversity for each metacommunity and, subsequently, regressed beta diversity on insect group, latitude, spatial extent, altitudinal range, and dataset properties (e.g., number of sites and percentage of presences). Within each metacommunity...

Reducing complexity in qualitative comparative analysis (QCA): remote and proximate factors and the consolidation of democracy

SCHNEIDER, Carsten Q.; WAGEMANN, Claudius
Fonte: Instituto Universitário Europeu Publicador: Instituto Universitário Europeu
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
55.86%
Comparative methods based on set theoretic relationships such as 'fuzzy set Qualitative Comparative Analysis' (fs/QCA) represent a useful tool for dealing with complex causal hypotheses in terms of necessary and sufficient conditions under the constraint of a medium-sized number of cases. However, real-world research situations might make the application of fs/QCA difficult in two respects - namely, the complexity of the results and the phenomenon of limited diversity. We suggest a two-step approach as one possibility to mitigate these problems. After introducing the difference between remote and proximate factors, the application of a two-step fs/QCA approach is demonstrated analyzing the causes of the consolidation of democracy. We find that different paths lead to consolidation, but all are characterized by a fit of the institutional mix chosen to the societal context in terms of power dispersion. Hence, we demonstrate that the application of fs/QCA in a two-step manner helps to formulate and test equifinal and conjunctural hypotheses in medium-size N comparative analyses, and thus to contribute to an enhanced understanding of social phenomena.

Tiger Economies Under Threat : A Comparative Analysis of Malaysia's Industrial Prospects and Policy Options

Yusuf, Shahid; Nabeshima, Kaoru
Fonte: World Bank Publicador: World Bank
Tipo: Publications & Research :: Publication; Publications & Research :: Publication
ENGLISH
Relevância na Pesquisa
65.9%
The Southeast Asian Tigers feel threatened. Even though their growth rates have remained above the average for the world and also above the average for developing countries, their economic performance falls short of that in the first half of the 1990s. The underlying worry is that it presages the beginning of a downward trend, the harbingers of which are lower rates of investment, persistently low rates of total factor productivity, and low levels of innovativeness. The Southeast Asian Tigers' worries motivate three questions, which this book attempts to answer. First, are the Tigers rightly threatened by a creeping economic sclerosis or what some observers are calling the middle-income trap? Second, if the threat is real, what are the underlying causes? Third, are there ways of neutralizing the problems and at least maintaining if not raising the growth rates of the recent past? This book will respond to these questions by means of a comparative analysis of the Tiger economies that is centered on Malaysia. This analysis draws on a comprehensive set of techniques and indicators to assess competitive pressures...

A comparative analysis reveals weak relationships between ecological factors and beta diversity of stream insect metacommunities at two spatial levels

Heino, Jani; Melo, Adriano S.; Bini, Luis Mauricio; Altermatt, Florian; Al-Shami, Salman A.; Angeler, David G.; Bonada, Nuria; Brand, Cecilia; Callisto, Marcos; Cottenie, Karl; Dangles, Olivier; Dudgeon, David; Encalada, Andrea; Gothe, Emma; Gronroos, Mir
Fonte: brasil; Programa de Pós-Graduação em Ecologia e Evolução Publicador: brasil; Programa de Pós-Graduação em Ecologia e Evolução
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
65.81%
v. 5, p. 1235-1248, mar., 2015; The hypotheses that beta diversity should increase with decreasing latitude and increase with spatial extent of a region have rarely been tested based on a comparative analysis of multiple datasets, and no such study has focused on stream insects. We first assessed how well variability in beta diversity of stream insect metacommunities is predicted by insect group, latitude, spatial extent, altitudinal range, and dataset properties across multiple drainage basins throughout the world. Second, we assessed the relative roles of environmental and spatial factors in driving variation in assemblage composition within each drainage basin. Our analyses were based on a dataset of 95 stream insect metacommunities from 31 drainage basins distributed around the world. We used dissimilaritybased indices to quantify beta diversity for each metacommunity and, subsequently, regressed beta diversity on insect group, latitude, spatial extent, altitudinal range, and dataset properties (e.g., number of sites and percentage of presences). Within each metacommunity, we used a combination of spatial eigenfunction analyses and partial redundancy analysis to partition variation in assemblage structure into environmental...

Human capital in the knowledge-based society: comparative analysis: Romania-Portugal

Martins, Dora; Dindire, Laura-Maria
Fonte: Constantin Brancoveanu University Publicador: Constantin Brancoveanu University
Tipo: Artigo de Revista Científica
Publicado em //2013 ENG
Relevância na Pesquisa
65.87%
The current economic crisis has rushed even more the economists’ concerns to identify new directions for the sustainable development of the society. In this context, the human capital is crystallised as the key variable of the creative economy and of the knowledge-based society. As such, we have directed the research underlying this paper to identifying the most eloquent indicators of human capital to meet the demands of the knowledge-based society and sustainable development as well as towards achieving a comprehensive analysis of the human capital in the EU countries, respectively of a comparative analysis: Romania - Portugal. To carry out this paper, the methodology used is based on the interdisciplinary triangulation involving approaches from the perspective of human resource management, economy and economic statistics. The research techniques used consist of the content analysis and investigation of secondary data of international organisations accredited in the field of this research, such as: the United Nation Development Programme - Human Development Reports, World Bank - World Development Reports, International Labour Organisation, Eurostat, European Commission’s Eurobarometer surveys and reports on human capital. The research results emphasise both similarities and differences between the two countries under the comparative analysis and the main directions in which one has to invest for the development of human capital.

The Comparative Study of Disaster: A Social Organizational Approach

Dynes, Russell R.
Fonte: Disaster Research Center Publicador: Disaster Research Center
Tipo: Outros Formato: 585147 bytes; application/pdf
EN_US
Relevância na Pesquisa
55.85%
Disasters can provide an exceptional opportunity for the comparative analysis of social systems, Disaster events are particularly useful for comparative purposes since they activate a variety of structures and processes with which the social system attempts to cope. In addition, disaster events allow for the observation of complex intergroup and interinstitutional relationships which in "normal times" usually emerge more slowly and segmentally. Such complexity is often slighted in most other comparative research since methodologies are used which place a premium on precision and abstraction rather than on the real complexities of social interrelationships. Disaster events are also useful for comparative purposes not only in understanding the more immediate adaptation of social systems but also because they are significant in understanding long-range social change.

From arrest to sentencing: A comparative analysis of the criminal justice system processing for rape crimes

Vargas,Joana Domingues
Fonte: Dados Publicador: Dados
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2008 EN
Relevância na Pesquisa
55.83%
The current article is intended to demonstrate the advantages of prioritizing an analysis of court caseload processing for a given type of crime and proceeding to a comparison of the results obtained from empirical studies in different countries. The article draws on a study I performed on rape cases tried by the court system in Campinas, São Paulo State, and the study by Gary LaFree on rape cases in the United States, based on data in Indianapolis, Indiana. The comparative analysis of determinants of victims' and law enforcement agencies' decisions concerning the pursuit of legal action proved to be productive, even when comparing two different systems of justice. This allowed greater knowledge of how the Brazilian criminal justice system operates, both in its capacity to identify, try, and punish sex offenders, and in terms of the importance it ascribes to formal legal rules in trying rape cases, in comparison to the American criminal justice system.