Dynamic Time-domain Duplexing for Self-backhauled Millimeter Wave Cellular Networks

Millimeter wave (mmW) bands between 30 and 300 GHz have attracted considerable attention for next-generation cellular networks due to vast quantities of available spectrum and the possibility of very high-dimensional antenna ar-rays. However, a key issue in these systems is range: mmW signals are extremely vulnerable to shadowing and poor high-frequency propagation. Multi-hop relaying is therefore a natural technology for such systems to improve cell range and cell edge rates without the addition of wired access points. This paper studies the problem of scheduling for a simple infrastructure cellular relay system where communication between wired base stations and User Equipment follow a hierarchical tree structure through fixed relay nodes. Such a systems builds naturally on existing cellular mmW backhaul by adding mmW in the access links. A key feature of the proposed system is that TDD duplexing selections can be made on a link-by-link basis due to directional isolation from other links. We devise an efficient, greedy algorithm for centralized scheduling that maximizes network utility by jointly optimizing the duplexing schedule and resources allocation for dense, relay-enhanced OFDMA/TDD mmW networks. The proposed algorithm can dynamically adapt to loading, channel conditions and traffic demands. Significant throughput gains and improved resource utilization offered by our algorithm over the static, globally-synchronized TDD patterns are demonstrated through simulations based on empirically-derived channel models at 28 GHz.Comment: IEEE Workshop on Next Generation Backhaul/Fronthaul Networks - BackNets 201

Web Service Testing and Usability for Mobile Learning

Based on the summary of recent renowned publications, Mobile Learning (ML) has become an emerging technology, as well as a new technique that can enhance the quality of learning. Due to the increasing importance of ML, the investigation of such impacts on the e-Science community is amongst the hot topics, which also relate to part of these research areas: Grid Infrastructure, Wireless Communication, Virtual Research Organization and Semantic Web. The above examples contribute to the demonstrations of how Mobile Learning can be applied into e-Science applications, including usability. However, there are few papers addressing testing and quality engineering issues – the core component for software engineering. Therefore, the major purpose of this paper is to present how Web Service Testing for Mobile Learning can be carried out, in addition to re-investigating the influences of the usability issue with both quantitative and qualitative research methods. Out of many mobile technologies available, the Pocket PC and Tablet PC have been chosen as the equipment; and the OMII Web Service, the 64-bit .NET e-portal and the GPS-PDA are the software tools to be used for Web Service testing

Undesirable Outputs’ Presence in Centralized Resource Allocation Model

Data envelopment analysis (DEA) is a common nonparametric technique to measure the relative efficiency scores of the individual homogenous decision making units (DMUs). One aspect of the DEA literature has recently been introduced as a centralized resource allocation (CRA) which aims at optimizing the combined resource consumption by all DMUs in an organization rather than considering the consumption individually through DMUs. Conventional DEA models and CRA model have been basically formulated on desirable inputs and outputs. The objective of this paper is to present new CRA models to assess the overall efficiency of a system consisting of DMUs by using directional distance function when DMUs produce desirable and undesirable outputs. This paper initially reviewed a couple of DEA approaches for measuring the efficiency scores of DMUs when some outputs are undesirable. Then, based upon these theoretical foundations, we develop the CRA model when undesirable outputs are considered in the evaluation. Finally, we apply a short numerical illustration to show how our proposed model can be applied

Federated Embedded Systems – a review of the literature in related fields

This report is concerned with the vision of smart interconnected objects, a vision that has attracted much attention lately. In this paper, embedded, interconnected, open, and heterogeneous control systems are in focus, formally referred to as Federated Embedded Systems. To place FES into a context, a review of some related research directions is presented. This review includes such concepts as systems of systems, cyber-physical systems, ubiquitous computing, internet of things, and multi-agent systems. Interestingly, the reviewed fields seem to overlap with each other in an increasing number of ways

The Economics of Water Resource Allocation: Valuation Methods and Policy Implications

In this chapter a ‘watershed economics approach’ that could be applied in Cyprus is proposed which is composed of two important stages. In Stage I economic valuation techniques are used to establish the economic value of the competing demands for surface and groundwater, incorporating where necessary an analysis of water quality. The valuation exercise allows the objective balancing of demands based upon the equi-marginal principle to achieve economic efficiency. In Stage II a policy impact analysis is proposed which addresses issues of social equity and the value of water for environmental/ecological purposes. The analysis is undertaken within the confines of the watershed; the most natural unit for the analysis of water allocation and scarcity since it determines the hydrological links between competing users and thus the impacts of one user upon another. The methodology is encapsulated by a case study of the Kouris watershed in Cyprus

Great Idea, Now What? Three Essays Examining The Relationship Between Organization Design And Commercialization Of Knowledge

Innovation is a key driver of a firm’s overall performance. Within an organization, innovation involves multiple actors transforming a firm’s knowledge into a final market offering. How an organization is designed can shape this transformation by influencing actors’ behaviors and interactions. However, despite prior studies, our understanding of the relationship between organization design and innovation is somewhat limited. In this dissertation, I offer a framework in which I conceptualize innovation as a process consisting of upstream tasks around invention, and downstream tasks around product development and commercialization. This enables me to combine both knowledge- and incentives- based views of the firm to develop a more complete theoretical understanding of the relationship between organization design and innovation. The design attribute I focus upon is the degree of organizational centralization. On the one hand, more centralized designs are associated with enhanced intra-organizational knowledge flows, which can enhance innovation. On the other hand, more decentralized designs are associated with higher observability of effort and facilitate the more effective use of incentives, which can increase innovation efforts. I empirically examine this trade-off in the context of the pharmaceutical industry. I use a unique dataset of firms’ patents, clinical trials, sales and organization structures supplemented by 61 interviews with senior managers from 28 of my sample firms. I find that greater decentralization while yielding higher numbers of inventions is associated with less original inventions, and fewer inventions progressing through the earlier stages of development. However, greater decentralization is associated with more inventions progressing through the later stages of development and greater sales of new products as a proportion of total sales. Further, I find that firms with decentralized Research & Development units are associated with a higher proportion of externally sourced inventions primarily driven by licensing. This dissertation contributes to the organization design and innovation literatures by highlighting where (in the organization) and when (in the innovation process) design choices can impact both how firms innovate as well as their innovation outcomes

Does Local School Control Raise Student Outcomes?: Evidence on the Roles of School Autonomy and Parental Participation

School autonomy and parental participation have been frequently proposed as ways of making schools more productive. Less clear is how governments can foster decentralized decision-making by local schools. This paper shows that across eight Latin-American countries, most of the variation in local control over school decisions exists within and not between countries. That implies that the exercise of local authority to manage schools is largely a local choice only modestly influenced by constitutional stipulations regarding jurisdiction over school personnel, curriculum and facilities. As a consequence, estimated impacts of local school autonomy, parental participation or school supplies on student performance must account for the endogeneity of local efforts to manage schools. Empirical tests confirm that local managerial effort by the principal and the parents and the adequacy of school supplies are strongly influenced by parental human capital and the size and remoteness of the community, and that these effects are only partially moderated by central policies regarding the locus of control over the schools. Correcting for endogeneity, parental participation and adequacy school supplies have strong positive effects on 4th grade test performance, but school autonomy has no discernable impact on school outcomes.autonomy; achievement; education; parental participaton; school inputs; test scores; Latin America

Economics of Water Quality Protection from Nonpoint Sources: Theory and Practice

Water quality is a major environmental issue. Pollution from nonpoint sources is the single largest remaining source of water quality impairments in the United States. Agriculture is a major source of several nonpoint-source pollutants, including nutrients, sediment, pesticides, and salts. Agricultural nonpoint pollution reduction policies can be designed to induce producers to change their production practices in ways that improve the environmental and related economic consequences of production. The information necessary to design economically efficient pollution control policies is almost always lacking. Instead, policies can be designed to achieve specific environmental or other similarly related goals at least cost, given transaction costs and any other political, legal, or informational constraints that may exist. This report outlines the economic characteristics of five instruments that can be used to reduce agricultural nonpoint source pollution (economic incentives, standards, education, liability, and research) and discusses empirical research related to the use of these instruments.water quality, nonpoint-source pollution, economic incentives, standards, education, liability, research, Environmental Economics and Policy,

Change and Transformation in Asian Industrial Relations

Authors argue that industrial relations systems change due to shifts in the constraints facing those systems, and that the most salient constraints facing IR systems in Asia have shifted from those of maintaining labor peace and stability in the early stages of industrialization, to those of increasing both numerical and functional flexibility in the 1980s and 1990s. The evidence to sustain the argument is drawn from seven “representative” Asian IR systems: Japan, South Korea, Singapore, Malaysia, the Philippines, India, and China. They also distinguish between systems that have smoothly adapted (Singapore, Malaysia, and the Philippines) and systems that have fundamentally transformed (China and South Korea), and hypothesize about the reasons for this difference