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Galaxy clustering encodes information about the values of cosmological parameters and also about the physical processes behind galaxy formation and evolution. The GALFORM semi-analytical model is the theoretical approach we used to model galaxy formation. We start by studying the luminosity dependence of galaxy clustering which is measured accurately in the local Universe. We have compared the clustering predictions of three publicly available galaxy formation models with clustering measurements from the 2dFGRS and found that two new processes need to be included in order to understand the observed clustering. We then study the distribution of cold gas in dark matter haloes central to the processes of galaxy formation. We present the cold gas mass function and its evolution with redshift. We have found that the clustering predicted by the semi-analytic models agrees well with the HIPASS measurements of Meyer et al. (2007). We have calculated effective volume for redshift surveys planned with Square Kilometre Array (SKA) and compared with that of the optical Euclid mission. Finally, we study the clustering of faint extragalactic sources which are one of the foregrounds in PLANCK maps. We predict the clustering of faint extragalactic sources using a hybrid GRASIL+GALFORM+N-body model. We have compared the hybrid scheme with analytic clustering estimates. On large scales the two approaches agree, but for multipoles with l>500 the results differ significantly, with the hybrid approach being the more accurate.

The central aim of this thesis is to investigate how a collaborative partnership approach as presented in contemporary planning theories can be applied to, and improve, a process of integrated waterside revitalisation. The emergence of a new model of governance, bringing together governmental and non-governmental forces to achieve the policy goal, calls for a novel form of partnership driven by interdependence and networking between a range of actors. Although this approach is often described as 'collaborative planning', there is widespread acknowledgement that the 'new' practice has operational difficulties. Collaborative planning has raised issues about how common values can be forged and applied in a real-life context, especially in the face of political inequality. This thesis draws on the results of a research project investigating a concrete example of collaborative partnerships, the Mersey Basin Campaign in the North West of England. The Campaign is a government-sponsored 25-year initiative that aims to improve water quality and the waterside environments of the Mersey Basin, a heavily urbanised area containing the two conurbations of Merseyside and Greater Manchester. In carrying out the study, six detailed case studies within the Campaign's activities have been investigated; about 40 semi-structured interviews have been undertaken, and over 25 meetings and field works have been observed. The study investigated the establishment and operation of a particular collaborative partnership according to a four-stage life cycle of partnerships. By exploring the six cases of collaborative practice through the views of practitioners, the research has shown how collaborative efforts can be made in a real-life context. The results showed that waterside sustainability issues were essential to tackling a river basin ecosystem management by creating a win-win strategy for wider stakeholders. The sustainability issue however, was not a top priority for all key stakeholders in deciding whether or not to put their money, time and efforts into the partnership. The research showed that funding availability is the best way to attract reluctant stakeholders, although partner organisations seemed not to be interested in implementing the tasks of the partnership once the initial excitement of funding availability had died away. There is, therefore, the partnerships need to develop an understanding of the collaborative approach among stakeholders and to change their attitudes towards a collaborative form of planning practice. Collaborative partnerships need different implementation processes to tackle different problems in the face of the complexity of waterside agendas; some planning processes require continuity of leadership, whilst others need bottom-up approaches. In this context, the study identified three key aspects of integrated waterside revitalisation; consensus building, facilitation, and open participation. It also developed a mechanism of collaborative partnership service delivery in coordinating a top-down approach and a bottom-up approach. The study has shown that the role of representatives linking their parent organisations to the partnership is fundamental for effective service delivery. It has been seen that once the representatives have shared ownership of the partnership, they act as a catalyst to stimulate and motivate action from their parent organisations.

One of the most exciting tools that has entered our life in recent years is machine learning. The family of cognitive learning algorithms has already proved to bring convenience in many aspects considerably in our daily life. However, it is still unclear how machine learning can be utilized and create incremental value over existing information technologies and algorithms. This dissertation examines value creation with machine learning and compares its value to other competing systems. In the first two essays, we begin with an examination of the forecasting accuracy of machine learning algorithms compared to other traditional econometric models in predicting daily demand cases at a theme park. In the first essay (Chapter 2), we find improvements in machine learning algorithms' prediction accuracy in nonlinear and non-stationary daily demand forecasting. In the second essay (Chapter 3), we create a deep-learning neural network using a Human-in-the-Loop (HITL) approach. This chapter shows that the HITL approach outperforms prior approaches in prediction accuracy & consistency and in (in)direct economic benefits over other benchmarks. These results indicate that human expertise complements, rather than substitutes, machine learning. Also, the HITL approach performs better in demand prediction with sudden changes, bringing considerable advantages to business practices. In Chapter 4, we show the existence of price dispersion online. We leverage a machine learning application to measure information asymmetry in this research context. The analysis finds robust evidence of value creation with machine learning. The last chapter discusses implications and limitations for academia and practice for future machine learning applications, investments, and value creation research.

The purpose of this study is to suggest the necessity of and alternative strategies for senior-friendly pastoral care to achieve sustained church growth amid the growing phenomenon of aging in Korean society. The recent aging of Korean society also has effects on changes in church members. As the ratio of senior members becomes increasingly high, pastoral alternative strategies for coping with it has also been urgently needed. The problem is that although this social phenomenon was already foreseen several years ago, there are insufficient practical strategies for pastoral care to deal with it. The researcher first conducts biblical, theological, historical, and sociological investigations into the necessity and value of senior ministry through literature review. Further, the strengths and weaknesses of senior ministries in six churches, which serve as models of senior ministry among mid-sized churches in large cities, are compared and analyzed through case study research. From this, the reasons why the methodology of senior-friendly ministry should be emphasized across pastoral care for seniors (worship, education, mission & evangelism, service & outreach, and fellowship) are revealed, and the senior ministry at Shinlim Central Church, which achieved church growth through the strategic application of senior-friendly ministries developed from this perspective, is introduced. The evaluation of the ministries is verified through a questionnaire survey of participants. This study offers practical methods for pastoral care in preparation for the aging of church members, thereby proposing one ministry strategy for more efficient pastoral care for seniors.

This study aims to comprehend the contextual backgrounds, communicative behaviors, and cultural consequences of South Korean adolescents who are sent to the United States for the purpose of education. Globalization, the recent economic affluence of Koreans, and a long tradition of `education fever,' has created a new trend of sending young children and adolescents alone to the United States in order to learn English. Three different levels of socio-cultural and historical backgrounds are provided in order to explain this phenomenon: the modern Korean perspective on education, the contemporary world of globalization, and Korean developmentalism. This study is composed of four basic research questions: (1) Why are these young adolescents sent to the United States by their parents?, (2) How do they live in the United States where everything is strange to them?, (3) how do they attempt to use new com techs to cope? (4) How successful are they at coping? and (4) How will their cultural identity be shaped? Based on these questions, this study conducts a series of in-depth interviews with young sojourners in Oklahoma City, Boston, and Dallas. The qualitative study, which is largely guided by grounded theory and phenomenology, divides into two main sections: the first section provides contextual background about their everyday lives in the United States. The second section mainly focuses on their communicative behavior and their use of new communication technologies. Findings of this research show that many of these young sojourners are suffering quite traumatically by living without parents and proper peer relationships. Social media have proven to not be adequate replacements for these young people and their normative social and psychological development. Being completely isolated in the US context, these young people spend much time alone in their private space using the Internet and consuming Korean media content. Cultural consequences in relation to their identity formation reflect the complex nature of the globalized world and the limitations of social media to satisfy the social needs of young people. This study is eventually expected to provide a ground for a refutation of the functionalist tradition of intercultural communication research and to develop new perspectives on internationally relocated populations in the age of globalization and advanced technology.

The demands of Internet applications have grown significantly in terms of required resources and types of services. Overlay networks have emerged to accommodate such applications by implementing more services on top of IP (Internet Protocol). However, while overlay networks are successful in circumventing limitations of IP, the task of building and maintaining an overlay network is still challenging. In an overlay network, participating hosts are virtually fully-connected through the underlying Internet. However, since the quality of overlay connections varies, the performance of the overlay network is dependent on which connections are chosen to be utilized. Therefore, maintaining a “good” overlay network topology is crucial in achieving high performance. To demonstrate how much performance gain can be achieved through topology changes, a distributed algorithm to build an overlay multicast tree is proposed for streaming media distribution. The algorithm finds an optimal tree such that the average bandwidth of receivers is maximized under an abstract network model. However, increasing bandwidth does not necessarily lead to a better overlay topology; in overlay networks, interference between overlay connections should be taken into account. Since such interference occurs when different overlay connections pass through a congested link simultaneously, detecting congestion shared by multiple overlay connections is necessary to avoid bottlenecks. For shared congestion detection, a novel technique called DCW (Delay Correlation with Wavelet denoising) is proposed. Previous techniques to detect shared congestion have limitations in applying to overlay networks; they assume a common source or destination node, drop-tail queueing, or a single point of congestion. However, DCW is applicable to any pair of paths on the Internet without such limitations. It employs a signal processing method, wavelet denoising, to separate queueing delay caused by network congestion from various other delay variations. The proposed technique is evaluated through both simulations and Internet experiments. They show that for paths with a common synchronization point, DCW provides faster convergence and higher accuracy while using fewer packets than previous techniques. Furthermore, DCW is robust and accurate without a synchronization point; more specifically, it can tolerate a synchronization offset of up to one second between two packet flows. Because DCW is designed to detect shared congestion between a pair of paths, there is a concern about scalability when it is used in a large-scale overlay network. To cluster N paths, a straightforward approach of using pairwise tests would require O(N2 ) time complexity. To address this issue, a scalable approach to cluster Internet paths using multidimensional indexing is presented. By storing per-path data in a multidimensional space indexed using a tree-like structure, the computational complexity of clustering is reducible to O(N log N). The indexing overhead can be further improved by reducing dimensionality of the space through the wavelet transform. Computation cost is kept low by using the same wavelet transform for both denoising in DCW and dimensionality reduction. The proposed approach is evaluated using simulations and found to be effective for large N. The tradeoff between indexing overhead and clustering accuracy is shown empirically. As a case study, an algorithm that improves overlay multicast topology is designed. Because overlay multicast forwards data without support from routers, data may be delivered multiple times over the same physical link, causing a bottleneck. This problem is more serious for applications demanding high bandwidth such as multimedia distribution. Although such bottlenecks can be removed by overlay topology changes, a na¨ıve approach may create bottlenecks in other parts of the network. The proposed algorithm removes all bottlenecks caused by the redundant data delivery of overlay multicast, detecting such bottlenecks using DCW. In a case where the source rate is constant and the available bandwidth of each link is not less than the rate, the algorithm guarantees that every node receives at the full source rate. Simulation results show that even in a network with a dense receiver population, the algorithm finds a tree that satisfies all the receiving nodes while other heuristic-based approaches often fail. A similar approach to finding bottlenecks and removing them through topology changes is applicable to other types of overlay networks. This research will enable bandwidth-demanding applications to build more efficient overlay networks to achieve higher throughput.