Less Is More: A Comprehensive Framework for the Number of Components of Ensemble Classifiers

The number of component classifiers chosen for an ensemble greatly impacts the prediction ability. In this paper, we use a geometric framework for a priori determining the ensemble size, which is applicable to most of existing batch and online ensemble classifiers. There are only a limited number of studies on the ensemble size examining Majority Voting (MV) and Weighted Majority Voting (WMV). Almost all of them are designed for batch-mode, hardly addressing online environments. Big data dimensions and resource limitations, in terms of time and memory, make determination of ensemble size crucial, especially for online environments. For the MV aggregation rule, our framework proves that the more strong components we add to the ensemble, the more accurate predictions we can achieve. For the WMV aggregation rule, our framework proves the existence of an ideal number of components, which is equal to the number of class labels, with the premise that components are completely independent of each other and strong enough. While giving the exact definition for a strong and independent classifier in the context of an ensemble is a challenging task, our proposed geometric framework provides a theoretical explanation of diversity and its impact on the accuracy of predictions. We conduct a series of experimental evaluations to show the practical value of our theorems and existing challenges.Comment: This is an extended version of the work presented as a short paper at the Conference on Information and Knowledge Management (CIKM), 201

GOOWE: Geometrically Optimum and Online-Weighted Ensemble Classifier for Evolving Data Streams

Designing adaptive classifiers for an evolving data stream is a challenging task due to the data size and its dynamically changing nature. Combining individual classifiers in an online setting, the ensemble approach, is a well-known solution. It is possible that a subset of classifiers in the ensemble outperforms others in a time-varying fashion. However, optimum weight assignment for component classifiers is a problem which is not yet fully addressed in online evolving environments. We propose a novel data stream ensemble classifier, called Geometrically Optimum and Online-Weighted Ensemble (GOOWE), which assigns optimum weights to the component classifiers using a sliding window containing the most recent data instances. We map vote scores of individual classifiers and true class labels into a spatial environment. Based on the Euclidean distance between vote scores and ideal-points, and using the linear least squares (LSQ) solution, we present a novel, dynamic, and online weighting approach. While LSQ is used for batch mode ensemble classifiers, it is the first time that we adapt and use it for online environments by providing a spatial modeling of online ensembles. In order to show the robustness of the proposed algorithm, we use real-world datasets and synthetic data generators using the MOA libraries. First, we analyze the impact of our weighting system on prediction accuracy through two scenarios. Second, we compare GOOWE with 8 state-of-the-art ensemble classifiers in a comprehensive experimental environment. Our experiments show that GOOWE provides improved reactions to different types of concept drift compared to our baselines. The statistical tests indicate a significant improvement in accuracy, with conservative time and memory requirements.Comment: 33 Pages, Accepted for publication in The ACM Transactions on Knowledge Discovery from Data (TKDD) in August 201

Survey of the diagenesis process and effect these process on reservoir quality of the Kangan formation in South Pars Field

Kangan and Upper Dalan formations are forming reservoir sequence of the South Pars field. Litology of the kangan formation is carbonate and (limestone and dolomite with anhydrite intervals), so digenetic processes were very active in this formation and these processes have changeed the reservoir quality. Importances of the digenetic process are including dissolution, calcite cements, dolomitization, anhydritization, physical and chemical compaction and fracturing

Quality of Romantic Attachment, Forgiveness, and Altruism in Parents of Children with Special Needs and Parents of Regular School Children

The aim of the current study was to investigate the relationship between forgiveness, quality of romantic attachment with altruism in parents of children with special needs and regular school children. In this study, 275 individuals (144 parents of regular school children using cluster sampling and 131 parents of children with special needs using available sampling[procedure) were selected. In this study Enright forgiveness inventory (Enright, 1977), Adult Attachment Inventory (Hazen& Shaver, 1987), and altruism (Ashton & et al., 1998); were used. Analysis of data was performed by using multiple regression analysis. Results of the analysis revealed that in parents of regular school children there was a significant negative correlation between insecure attachment to spouse and cognitive, emotional and behavioral domain of forgiveness. Whereas in parents of exceptional children there was a significant negative correlation between insecure attachment to spouse and cognitive and behavioral dimensions of forgiveness. Multiple regression analysis revealed that in mothers of children with special needs and regular school children quality of attachment to the spouse was a significant variable in determining the forgiveness (cognitive, behavioral and emotional dimension of forgiveness). The quality of attachment is a significant variable in determining the magnitude of forgiveness

Immunomodulatory effects of human umbilical cord wharton's Jelly-Derived mesenchymal stem cells on differentiation, maturation and endocytosis of monocyte-derived dendritic cells

The Wharton's jelly of the umbilical cord is believed to be a source of mesenchymal stem cells (MSCs) which can be therapeutically applied in degenerative diseases. In this study, we investigated the immunomodulatory effect of umbilical cord derivedmesenchymal stem cells (UC-MSCs) and bone marrow-derived-mesenchymal stem cells (BM-MSCs) on differentiation, maturation, and endocytosis of monocyte-derived dendritic cells in a transwell culture system under laboratory conditions. Monocytes were differentiated into immature dendritic cells (iDCs) in the presence of GM-CSF and IL-4 for 6 days and then differentiated into mature dendritic cells (mDCs) in the presence of TNF-for 2 days. In every stage of differentiation, immature and mature dendritic cells were separately cocultured with UC-MSCs and BM-MSCs. The findings showed that UC-MSCs and BM-MSCs inhibited strongly differentiation and maturation of dendritic cells at higher dilution ratios (1:1). The BM-MSCs and UC-MSCs showed more inhibitory effect on CD1a, CD83, CD86 expression, and dendritic cell endocytic activity, respectively. On the other hand, these cells severely up-regulated CD14 marker expression. We concluded that UC-MSCs and BM-MSCs could inhibit differentiation, maturation and endocytosis in monocyte-derived DCs through the secreted factors and free of any cellcell contacts under laboratory conditions. As DCs are believed to be the main antigen presenting cells for naive T cells in triggering immune responses, it would be logical that their inhibitory effect on differentiation, maturation and function can decrease or modulate immune and inflammatory responses. Copyright © Spring 2013, Iran J Allergy Asthma Immunol. All rights reserved

Appraisal of intra-reservoir barriers in the Permo-Triassic successions of the Central Persian Gulf, Offshore Iran

Owing to their tightness, intra reservoir barriers have the potential to prevent homogenization of reservoir fluids and so cause compartmentalization. Identification of these barriers is an important step during reservoir evaluation. In order to achieve this, three main approaches: i) detailed petrographic and core analysis, ii) petrophysical studies (flow unit concept) and iii) geochemical analysis (strontium residual salt analysis) were applied systematically in the Permo-Triassic carbonate reservoirs (Dalan and Kangan formations) of a supergiant gas reservoir located in the Central Persian Gulf. Integration of these approaches has led to a fullclarification of the intra reservoir barriers. Petrographic examinations revealed the potential stratigraphic barriers to fluids flow created by various depositional/ diagenetic characteristics. Petrophysical data such as poroperm values, pore throat size distribution and scanning electron microscopy (SEM) analysis were used to differentiate the reservoir flow units from non-reservoir rock. According to different trends in 87Sr/86Sr ratios of residual salts, the existence of flow barriers was evaluated and proved. Finally, by integrating these approaches, three intra reservoir barriers were introduced in the studied reservoir interval. These intra reservoir barriers are depositional and diagenetic in nature and are located in stratal positions with sequence stratigraphic significance. The possibility of reservoir compartmentalization was evaluated in the studied wells, and then their existence was predicted at the adjacent fields. As shown in this study, integration of petrographic examinations with flow unit determination in a sequence stratigraphic framework has the potential for recognizing intra reservoir barriers and predicting compartmentalization of the studied Permo-Triassic reservoirs

Myocardial Defect Detection Using PET-CT: Phantom Studies

It is expected that both noise and activity distribution can have impact on the detectability of a myocardial defect in a cardiac PET study. In this work, we performed phantom studies to investigate the detectability of a defect in the myocardium for different noise levels and activity distributions. We evaluated the performance of three reconstruction schemes: Filtered Back-Projection (FBP), Ordinary Poisson Ordered Subset Expectation Maximization (OP–OSEM), and Point Spread Function corrected OSEM (PSF–OSEM). We used the Channelized Hotelling Observer (CHO) for the task of myocardial defect detection. We found that the detectability of a myocardial defect is almost entirely dependent on the noise level and the contrast between the defect and its surroundings

The generalized hyers-ulam stability of sextic functional equation in various matrix spaces

Using the fixed point method, we prove the generalized Hyers-Ulam stability of the followinggeneralized sextic functional equation Df (x, y):= f (mx+ y) +f (mx− y) +f(x+ my) +f(x− my)− (m4+ m2) [f(x+ y+f(x− y)] −2(m6− m4− m2+ 1) [f(x) + f(y)]in matrix fuzzy normed spaces. Furthermore, using the fixed point method, we also prove theHyers-Ulam stability of the above functional equation in matrix random normed spaces.Keywords: Hyers-Ulam stability; fixed point method; matrix fuzzy normed space; matrixrandom normed spaces; sextic functional equation

The role of mega-events in sustainable urban transformation and urban quality promotion

Tese de Doutoramento (Programa Doutoral em Engenharia Civil)This thesis developed a sustainable urban sport mega-event model for host cities providing a complete process from urban planning, management to the event organization. The proposed model is assembled through the reviewing of sport mega-events' impacts on host cities. The literature review previously undertaken explored sport mega-events' impacts and their relation with urban sustainability based on physical, environmental, economic and sociocultural dimensions. The research examines the alignment of event planning and implementation actions within a set of urban sustainable development objectives selected from a group of 63 indicators on a range of outcomes and impacts of the most recent sport mega-events. This thesis evaluated the role of mega-events in sustainable urban transformation and urban quality promotion in Rio de Janeiro, with the main objective of exploring if 2016 Olympics succeeded in transforming the city in a sustainable way through hosting sport mega-events. The impacts were then assessed through a survey given to Brazilian experts about the Olympics in the city of Rio de Janeiro. The survey indicates the same results as the literature review about the sport mega event impacts in developing countries. The experts' opinions pointed out that the huge expenditures on large-scale projects and sport infrastructures that are so different from daily requirements do not meet the needs of the majority of Rio's inhabitants. The statistical quantitative analysis of impacts intensity highlighted that this sport mega-event had much larger negative than positive impacts, in all four dimensions, especially in the environmental dimension. In order to gain a deeper understanding of the role of hosting the mega-events in urban transformations and quality promotion, an in-depth investigation especially in physical and environmental dimensions was undertaken for the case study of Rio de Janeiro. All these research techniques, literature review, modeling, assemblage of indicators, survey of experts and case study analysis of four Olympic zones, were relevant in detecting the challenges that a host city may face. Overall, the three fold evaluation including the survey on expert's views, sustainability assessment through impact indicators and also the evidence from the Olympic zones (Barra, Deodoro, Maracanã and Copacabana) validates the standpoint that there is little improvement in terms of sustainable urban transformation. This thesis also discussed the relationship between impact indicators and urban sustainability. A slight alignment was found in terms of eventrelated transport expansion in the city and green spaces improvement, especially in the Deodoro zone. Therefore, management system in cities of the developing countries often does not benefit from event-related transformation. In this way, effective governance of hosting a sport mega-event is necessary to drive sustainable development. The application of the proposed model helps to improve event planning, management and organization processes in order to achieve a more sustainable urban development in the host cities, especially in developing countries.Esta tese desenvolveu um modelo de megaevento desportivo urbano sustentável para as cidades anfitriãs, compreendendo todo o processo desde o planeamento urbano até à organização do evento. O modelo proposto foi construído com base na revisão bibliográfica sobre os impactos dos megaeventos desportivos nas cidades anfitriãs. A revisão da literatura realizada explorou os impactos dos megaeventos desportivos e sua relação com a sustentabilidade urbana, a partir de dimensões físicas, ambientais, económicas e socioculturais. A investigação analisou a implementação das ações de planeamento com a realização dos eventos, integrada em um conjunto de objetivos de desenvolvimento urbano sustentável selecionados a partir de um grupo de 63 indicadores relativos a resultados e impactos dos megaeventos desportivos mais recentes. Esta tese avaliou o papel dos megaeventos na transformação urbana sustentável e na promoção da qualidade urbana no Rio de Janeiro, com o objetivo de analisar se as Olimpíadas de 2016 conseguiram transformar a cidade de forma sustentável por meio da realização desse megaevento desportivo. Os impactos foram então avaliados por meio de um inquérito a especialistas brasileiros sobre as Olimpíadas na cidade do Rio de Janeiro. Os resultados deste inquérito são semelhantes aos obtidos na revisão da literatura sobre os impactos de mega eventos desportivo nos países em desenvolvimento. As opiniões dos especialistas realçam que apesar das despesas elevadas em projetos de grande escala e infraestruturas desportivas, estas não respondem às necessidades diárias da maioria dos habitantes do Rio de Janeiro. A análise estatística quantitativa da intensidade dos impactos destaca que este megaevento desportivo teve muito mais impactos negativos do que positivos, nas quatro dimensões, especialmente na ambiental. A fim de obter uma compreensão aprofundada do papel dos megaeventos nas transformações urbanas e na promoção da qualidade urbana, realizou-se uma investigação detalhada, especialmente nas dimensões física e ambiental, para o estudo de caso do Rio de Janeiro. Todas estas técnicas de análise, revisão da literatura, modelação, seleção de indicadores, auscultação da opinião de especialistas e análise de estudo de caso das quatro zonas olímpicas, foram relevantes na determinação dos desafios que uma cidade-anfitriã pode enfrentar. A avaliação tríplice, incluindo a perspetiva dos especialistas, a avaliação da sustentabilidade por meio de indicadores de impacto e também a análise detalhada das zonas olímpicas (Barra, Deodoro, Maracanã e Copacabana), valida a hipótese da ocorrência de pequenas melhorias de transformação urbana sustentável. Esta tese também analisa a relação entre indicadores de impacto e sustentabilidade urbana. Foi encontrada uma correlação, ainda que fraca, entre o megaevento e a expansão do sistema de transporte na cidade e o acréscimo de espaços verdes, especialmente na zona de Deodoro. Em suma, os sistemas de planeamento e gestão urbana das cidades anfitriãs dos países em desenvolvimento, não beneficiam muitas vezes da transformação relacionada com o megaevento. Neste contexto, a relevância da governança é determinante para impulsionar o desenvolvimento sustentável. A aplicação do modelo proposto permite melhorar os processos de planeamento, gestão e organização de megaeventos, especialmente nos países em desenvolvimento

PERFORMANCE EVALUATION OF TWO NEW SEISMIC RESISTANT DIAGRID FRAMING SYSTEMS

The diagrid system offers a visually appealing and structurally efficient structural system for gravity load bearing. The architectural elegancy and high structural redundancy of the diagrid structure makes it a desirable choice for tall building design. However diagrid structure is prone to high inelastic deformation demand during strong earthquakes. To address this issue of limited ductility and energy dissipation capacity in conventional diagrid framing, two new types of seismic resistant diagrid structural systems termed highly energy-dissipative ductile (HED) diagrid and hybrid diagrid framing systems are proposed in this research and their seismic performance is assessed. The proposed HED diagrid framing system provides a competitive design option in high seismic regions with its high ductility and improved energy dissipation capacity enabled by incorporating replaceable shear links interconnecting the diagonal members at their nodes. A parametric study has been conducted to investigate the effect of different design parameters on the seismic performance of this system. A new type of composite brace comprised of glass fiber reinforced polymer (GFRP)-tube confined concrete, steel core and post-tensioned tendons, is developed for self-centering diagrid members. The hysteretic behavior of a self-centering chevron assembly comprised of two inclined composite braces is subsequently examined. Constitutive modeling of GFRP-tube confined concrete with high confinement volumetric ratio is conducted with experimental data calibration under monotonic and cyclic compression. The constitutive model is implemented into a finite element analysis platform OpenSees to enable nonlinear analysis of complex structures utilizing this type of confined concrete elements. The self-centering chevrons are implemented in the lower stories of the hybrid diagrid framing system to form base diagonals with large stiffness, enhanced ductility and energy dissipation capability and enable a rocking behavior for the diagrid system. The structural characteristics and seismic behavior of these two new seismic resistant systems are demonstrated with a prototype 21-story building subjected to nonlinear static and dynamic analysis. The findings from nonlinear time history analysis verify that satisfactory seismic performance can be achieved by these structural systems subjected to design basis earthquakes in California, specifically showing re-centering behavior while all main structural elements remain elastic in both systems