This dissertation considers graph theoretic generalizations of the maximum clique problem. Models that were originally proposed in social network analysis literature, are investigated from a mathematical programming perspective for the first time. A social network is usually represented by a graph, and cliques were the first models of "tightly knit groups" in social networks, referred to as cohesive subgroups. Cliques are idealized models and their overly restrictive nature motivated the development of clique relaxations that relax different aspects of a clique. Identifying large cohesive subgroups in social networks has traditionally been used in criminal network analysis to study organized crimes such as terrorism, narcotics and money laundering. More recent applications are in clustering and data mining wireless networks, biological networks as well as graph models of databases and the internet. This research has the potential to impact homeland security, bioinformatics, internet research and telecommunication industry among others. The focus of this dissertation is a degree-based relaxation called k-plex. A distance-based relaxation called k-clique and a diameter-based relaxation called k-club are also investigated in this dissertation. We present the first systematic study of the complexity aspects of these problems and application of mathematical programming techniques in solving them. Graph theoretic properties of the models are identified and used in the development of theory and algorithms. Optimization problems associated with the three models are formulated as binary integer programs and the properties of the associated polytopes are investigated. Facets and valid inequalities are identified based on combinatorial arguments. A branch-and-cut framework is designed and implemented to solve the optimization problems exactly. Specialized preprocessing techniques are developed that, in conjunction with the branch-and-cut algorithm, optimally solve the problems on real-life power law graphs, which is a general class of graphs that include social and biological networks. Computational experiments are performed to study the effectiveness of the proposed solution procedures on benchmark instances and real-life instances. The relationship of these models to the classical maximum clique problem is studied, leading to several interesting observations including a new compact integer programming formulation. We also prove new continuous non-linear formulations for the classical maximum independent set problem which maximize continuous functions over the unit hypercube, and characterize its local and global maxima. Finally, clustering and network design extensions of the clique relaxation models are explored.

This thesis begins with the economic globalization, and uses secondary data analysis to explore the labor structural change and employment conditions in Taiwan under globalization. Then, using the social exclusion theory, through qualitative in-depth interview methods, this study explores the unemployment and re-employment experiences of the long-term unemployed and the marginally employed, as well as the economic, psychological, and social network exclusion in the process of employment to unemployment. This study also discusses the roles of government employment policies, familial and social relationship networks. Finally, policy suggestions are proposed according to related research discoveries. The study finds that: first, in terms of unemployment and re-employment experience, most laborers regard unemployment with a passive and external attribution attitude; this negatively influences emotions, interpersonal relationships, and later re-employment. While unable to return to the original career, unemployed laborers develop different life choices. Those who return to the labor market the earliest return because they succumb to economic pressure, becoming marginal workers who are willing to do any work, and the other kind are those who are continuously accumulate capital and convert it into employment resource; these are the active workers. On the other hand, there are two types of people who remain unemployed. One is the type that becomes waiting unemployed because they are unwilling to budge on employment conditions, and the other is the type that is limited by their own employment abilities and become helplessly unemployed. Additionally, unemployed people with different identities also have different life choices at their inability to return to their original careers. Secondly, from labor market exclusion to social exclusion: 1.Labor market exclusion and economic exclusion: unemployment results in decreased income, which further impairs daily living needs, basic medical care, and educational services, as well as stops one from participating in entertainment and leisure activities; these impact basic life opportunities and makes one feel more and more exclusion. 2. Labor market exclusion and psychological exclusion: emotional changes during unemployment are primarily affected by decreased income, but it is also affected by personal expectations of future re-employment. For the involuntarily unemployed, they feel a greater sense of lack of control and impotence over their lives. 3. Labor market exclusion and social relationship exclusion: as a result of lack of self esteem or economic considerations, the unemployed have significantly less social interaction, in a singularized network structure, which would provide relatively smaller economic or re-employment support. 4. Social networks have a positive influence on alleviating the multifaceted exclusion caused by unemployment, but the majority of unemployment laborers have significantly insufficient social network functions. Those who are unemployed with weak formal and informal social networks would fall into social exclusion, have a bleak outlook on the future and believe that there is no chance to extricate oneself from the various unfavorable situations caused by unemployment. ¡@¡@The end of the thesis also discusses some related issues, such as the unemployment issue (unemployment conceptualization? Who are the unemployed? Work or retire?), social exclusion issues (applicability of social exclusion theories? what is the role of the country in labor market exclusion? Does the employment policy cause social cohesion or social exclusion?), social structures, and individual action interactions. Finally, from labor market intervention, construction to social network, and proposes related policy suggestions to reverse social exclusion.

The invention of Internet affects human life style and also creates many innovations and applications of business models. Social Network Service, SNS, is an innovative application and business model in recently years. It changes the development and communication of current social network and gathers high-traffic viewers to create more business opportunities. However, what¡¦s value attracted users to use SNS. This study focuses the usages of SNS from the users of Taiwan area by empirical research. From the customer point of view, satisfaction and word-of-mouth could be relative to and affected by utilitarian value and hedonic value. Therefore, this study builds an applicable integrated model and uses Structural Equation Modeling, SEM, to analyze and approve the relations of constructs. The following is the conclusions of this study. (1) The theory of this study confirms fit indices in SEM, and cause and effect of each construct is very obvious to support it. (2) Utilitarian value can be measured by factors of sociality, convenience, and information availability; hedonic value can be measured by factors of adventure, escapism, and affiliation. (3) Utilitarian value and hedonic value affect customer satisfaction; customer satisfaction affects word-of-mouth. (4) Utilitarian value and hedonic value positively affect word-of-mouth, but providing a good customer satisfaction can enhance word-of-mouth. (5) Influence of hedonic value is higher than that of utilitarian value relative to customer satisfaction and word-of-mouth. It shows that the users prefer hedonic value in SNS. Therefore, this study can be the reference of business administration and academic research.

<p>The aim writing this thesis was to get an understanding about how Erasmus exchange students find their way in their new environment. Furthermore, to see what kind of resources are available for them and which they eventually use if they have a problem or just to make themselves feel more comfortable. The students' ages are between 20 and 23.</p><p>The thesis analyzes the strategies the exchange students are using. In detail, where they meet people and what is supporting them. It also analyzes resources the students are relying on and the satisfaction with the students' life at Växjö University.</p><p>The data were collected with eleven interviews. With the interviews was also handed out a questionnaire to the interviewed student.</p><p>The result shows that the living situation is a coefficient when it comes to socializing, in this case living in a corridor. Also, going out to the students' pub and attending Växjö International Students (VIS) activities. Erasmus exchange students tend to rely on resources in the home country which are the family or friends or they are likely to rely on other students from the same country or foreign students as well. The overall satisfaction of the students' life is on the upper third of the certailnly measurement.</p>

The number of children diagnosed with an autism spectrum disorder (ASD) who are being served in the public school system has increased dramatically in recent years. During an increased focus on inclusion within education, research shows that students with ASD educated in the general education classroom generally do not have as many friends as their peers without ASD. However, some students with ASD are found to have more friends than other students with ASD. Therefore, additional research must explore potential factors that may be influencing the success with which students with ASD form friendships within the general education classroom. Using a multiple case study ecological approach, this study examines child, peer, and general education teacher factors related to the friendship patterns of three male students with ASD in fourth or fifth grade general education classrooms. Results from this study indicate that consistent with previous research, some students with ASD are found to be more socially embedded within the social network of the general education classroom and report greater levels of social satisfaction than other students with ASD. Findings suggest that for the three participants within this study, having two solid friendships, regardless of the social status of the friends of the student with ASD, may be related to a higher level of social network status and lower levels of self-reported loneliness for students with ASD. Factors that were found to be important for the three target students in this study included quality of social skills, quality of friendship, understanding of the construct of friendship, and general education teacher experience level. Factors that were found to be less important for the three target students in this study included peer attitudes towards children with disabilities, teacher attitudes towards inclusion of students with autism, teacher knowledge of autism, and teacher knowledge and use of evidence-based practices. Possible explanations for these findings, as well as limitations, directions for future research, and implications are discussed.

Med denna uppsats har vi velat ta reda på hur singlar över 30 år upplever sitt singelskap samt hur de förhåller sig till att inleda partnerskap och att skaffa barn. Singel är ett begrepp som inrymmer många olika aspekter och perspektiv. Genom individuella intervjuer har vi tagit del av 4 kvinnliga singlar och 4 manliga singlars egna upplevelser, alla är över 30 år och bosatta i mellan Sverige. Vi har analyserat det empiriska materialet vi fått fram med hjälp av vår teoretiska utgångspunkt som berör modernitetens samhälle där individen skapar sin självidentitet och livsstil utifrån sin kontext. Singlarna har givit oss en bild av deras liv och deras inställning till den norm om parrelationer och att skaffa barn som finns i vårt samhälle. Det empiriska materialet vi fått tillgång till har tolkats och analyserats med hjälp av Grounded theory. Vårt resultat visar på individens strävan efter känslan av frihet och oberoende. Singlarna är nöjda över sin livsstil men uppger att det kan finnas en saknad av någon ibland. En ambivalens uppstår mellan deras känsla av frihet till den ensamhet de kan uppleva. Upplevelsen av singelskapet och synen på partnerskap och barn mellan män och kvinnor visar sig inte vara så olik. / In this paper we wanted to find out how singles over 30 years experience their position as singles and how they relate to initiate partnership and having children. Single is a term that covers a number of aspects and perspectives. Through individual interviews, we’ve taken note of 4 female and 4 male singles own experience, they’re all over 30 years old and live in central Sweden. We’ve analyzed the empirical material based on the knowledge from our theoretical basis on the modern society that reviles how the individuals creates their own identity and lifestyle. The singles have given us an understanding of their lifestyle and their attitude to the norm of intimate relationships and having children in our society. The empirical material we had access to has been interpreted and analyzed using the Grounded theory. Our results indicate that the experience of freedom and independence is a requisite to the individuals. The singles are pleased with their lifestyle but state that they, at times, yearn the intimacy from a relationship. A feeling of ambivalence occurs when their need for freedom collides with the loneliness they occasionally experience. The experience of solitude and views on partnership and having children between men and women turned out not to be very different.

Optimization is a mathematical technique that concerns the finding of maxima or minima of functions in some feasible region. There is no business or industry which is not involved in solving optimization problems. A variety of optimization techniques compete for the best solution. Particle Swarm Optimization (PSO) is a relatively new, modern, and powerful method of optimization that has been empirically shown to perform well on many of these optimization problems. It is widely used to find the global optimum solution in a complex search space. This thesis aims at providing a review and discussion of the most established results on PSO algorithm as well as exposing the most active research topics that can give initiative for future work and help the practitioner improve better result with little effort. This paper introduces a theoretical idea and detailed explanation of the PSO algorithm, the advantages and disadvantages, the effects and judicious selection of the various parameters. Moreover, this thesis discusses a study of boundary conditions with the invisible wall technique, controlling the convergence behaviors of PSO, discrete-valued problems, multi-objective PSO, and applications of PSO. Finally, this paper presents some kinds of improved versions as well as recent progress in the development of the PSO, and the future research issues are also given.

With the exponential growth of Facebook users worldwide, this platform for social network online has become a powerful tool to connect individuals and share information with each other. This study explores the phenomenal trend of utilizing a Facebook application called Causes to help users organize into online communities for a specific cause and mobilize their resources for disaster relief during the Haiti earthquake disaster. Two separate samples of 100 joiners each from the American Red Cross (ARC) Cause on Facebook were randomly selected before and after the Haiti earthquake disaster to examine the differences of the composition (i.e., attributes) and structure (i.e., relational ties) of each social network. The social network analysis performed for this thesis research intends to fill the gap of historical research literature on recruitment to activism and support provision following a disaster in the digital age of the 21 st century. The results of this study show how understanding the membership size of online communities, salient identity for the cause through organizational affiliations, interpersonal ties among the joiners, density of the network as well as gender diversity can be crucial recruitment factors to leverage for disaster relief efforts. The findings reveal a beneficial partnership between disaster relief organizations and online social networks in mobilizing their resources for a speedy response to disasters.

From 1961 to 1971 the United States and the Republic of South Vietnam used chemicals to defoliate the coastal and upload forest areas of Viet Nam. The most notorious of these chemicals was named Agent Orange, a weaponized herbicide made up of two chemicals that, when combined, produced a toxic byproduct called TCDD-dioxin. Studied suggest that TCDD-dioxin causes significant human health problems in exposed American and Vietnamese veterans, and possibly their children (Agency, U.S. Environmental Protection, 2011). In the years since the end of the Vietnam War, volumes of discourse about Agent Orange has been generated, much of which is now digitally archived and machine-readable, providing rich sites of study ideal for “big data” text mining, extraction and computation. This study uses a combination of tools and text mining scripts developed in Python to study the descriptive phrases four discourse communities used across 45 years of discourse to talk about key issues in the debates over Agent Orange. Findings suggests these stakeholders describe and frame in significantly different ways, with Congress focused on taking action, the New York Times article and editorial corpus focused on controversy, and the Vietnamese News Agency focused on victimization. Findings also suggest that while new tools and methods make lighter work of mining large sets of corpora, a mixed-methods approach yields the most reliable insights. Though fully automated text analysis is still a distant reality, this method was designed to study potential effects of rhetoric on public policy and advocacy initiatives across large corpora of texts and spans of time.

In the fast growing online social networks, one of the most commonly observed phenomena is the diffusion of information contents, behaviors or products through network members’ interactions. In this thesis, I study the diffusion phenomenon by examining the individual-level adoption decision, both theoretically and empirically. In the three essays, I study the effects of the strength of the interpersonal tie and the social network characteristics on a potential adopter’s decision-making, and investigate the measurement of network members’ influences. / text