Analysis of probability of non-zero secrecy capacity for multi-hop networks in presence of hardware impairments over Nakagami-m fading channels

In this paper, we evaluate probability of non-zero secrecy capacity of multi-hop relay networks over Nakagamim fading channels in presence of hardware impairments. In the considered protocol, a source attempts to transmit its data to a destination by using multi-hop randomize-and-forward (RF) strategy. The data transmitted by the source and relays are overheard by an eavesdropper. For performance evaluation, we derive exact expressions of probability of non-zero secrecy capacity (PoNSC), which are expressed by sums of infinite series of exponential functions and exponential integral functions. We then perform Monte Carlo simulations to verify the theoretical analysis.Web of Science25478277

Analysis of Probability of Non-zero Secrecy Capacity for Multi-hop Networks in Presence of Hardware Impairments over Nakagami-m Fading Channels

In this paper, we evaluate probability of non-zero secrecy capacity of multi-hop relay networks over Nakagami-m fading channels in presence of hardware impairments. In the considered protocol, a source attempts to transmit its data to a destination by using multi-hop randomize-and-forward (RF) strategy. The data transmitted by the source and relays are overheard by an eavesdropper. For performance evaluation, we derive exact expressions of probability of non-zero secrecy capacity (PoNSC), which are expressed by sums of infinite series of exponential functions and exponential integral functions. We then perform Monte Carlo simulations to verify the theoretical analysis

Supply assurance in the nuclear fuel cycle

Errata sheet inserted.The economic, technical and political issues which bear on the security of nuclear fuel supply internationally are addressed. The structure of international markets for nuclear fuel is delineated; this includes an analysis of the political constraints on fuel availability, especially the connection to supplier nonproliferation policies. The historical development of nuclear fuel assurance problems is explored and an assessment is made of future trends in supply and demand and in the political context in which fuel trade will take place in the future. Finally, key events and policies which will affect future assurance are identified.U.S. Dept. of Energy Contract no. 426365-S

Smart Wireless Sensor Networks

The recent development of communication and sensor technology results in the growth of a new attractive and challenging area - wireless sensor networks (WSNs). A wireless sensor network which consists of a large number of sensor nodes is deployed in environmental fields to serve various applications. Facilitated with the ability of wireless communication and intelligent computation, these nodes become smart sensors which do not only perceive ambient physical parameters but also be able to process information, cooperate with each other and self-organize into the network. These new features assist the sensor nodes as well as the network to operate more efficiently in terms of both data acquisition and energy consumption. Special purposes of the applications require design and operation of WSNs different from conventional networks such as the internet. The network design must take into account of the objectives of specific applications. The nature of deployed environment must be considered. The limited of sensor nodes� resources such as memory, computational ability, communication bandwidth and energy source are the challenges in network design. A smart wireless sensor network must be able to deal with these constraints as well as to guarantee the connectivity, coverage, reliability and security of network's operation for a maximized lifetime. This book discusses various aspects of designing such smart wireless sensor networks. Main topics includes: design methodologies, network protocols and algorithms, quality of service management, coverage optimization, time synchronization and security techniques for sensor networks

Logistics horizontal collaboration:an agent-based simulation approach to model collaboration dynamics

Underutilized capacity, long shipping lead time, high cost and lack of sufficient scale are examples of logistics inefficiencies that have troubled many supply chain operations. Logistics horizontal collaboration (LHC) is believed to be an innovative approach to tackle the increasing logistics challenges. This kind of collaborative logistics is quickly gaining momentum in practice but relevant contributions in literature are scarce. So far it remains unclear how LHC could be structured and operated given the limited understanding of the various characteristics and forms of LHC between companies. Furthermore, the explicit impact of LHC on the participating partners, as well as on the supply chain system is understudied. Very few studies have explored the process of collaboration and how it links to performance behaviours. Case studies and Agent-Based Simulation are employed in this thesis to study the research gaps identified above. Case studies are initially conducted to examine the key elements which can support the design of LHC, and to make a classification of models for collaboration. These are followed by Agent-Based Simulation to model a typical collaboration process and work out what benefits would emerge if participating in horizontal collaboration and how the collaboration can produce the impacts on the supply chain operations for individuals and the system as a whole. The case studies suggest that “collaboration structures”, “collaboration objectives”, “collaboration intensity”, and “collaboration modes” are the four key elements critical to the design of a LHC project. Each element represents an important aspect of the collaboration and exhibits different characteristics and forms. Based on these key elements, several typologies are derived which together provide a comprehensive view to explain the different types of LHC in practice. The simulation modelling demonstrates that LHC can significantly benefit the logistics efficiency in terms of capacity utilization and customer service in the sense of order fill-rate, and such beneficial effects are consistently observed in different supply chain environments. In particular, LHC can produce better logistics performance in a relationship-based supply chain network where downstream customers can support upstream shippers with more stable and predictable demand. On the other hand, information sharing in the collaboration, for the most part, does not facilitate the higher collaboration gains for partners. Specifically, sharing either the demand or supply information in the horizontal collaboration is not helpful in increasing collaboration gains. Hence there is a difference for the value of information sharing in the context of horizontal collaboration as opposed to vertical collaboration, the latter of which is often justified as providing more beneficial gains. The research findings provide insights for practitioners and scholars about how to develop a type of collaboration project or study, as well as enabling a better understanding of the dynamic collaboration effects

The experiences of Canadian children of prisoners

Long hidden from academic scrutiny, children of prisoners have recently become the subjects of much academic study, through a variety of disciplines and methods. However many issues within this topic remain under-examined. This study aimed to explore two such issues: the self-reported experiences of children of prisoners, and children in the Canadian context. This thesis analyses the results of qualitative interviews with children aged 6-17 who currently have a parent in prison (N=22). Employing a ‘sociology of childhood’ framework, this project seeks to centre the voice of children themselves, privileging their own views and meaning-making. These data are supplemented with other findings to provide context to children’s narratives, including: interviews with these children’s caregivers in the community (N=12); interviews with a variety of key informants; observations gathered during extensive recruitment efforts with families of prisoners; and reviews of existing policy documents and service provision specific to parental incarceration. The thesis begins with a review of the existing literature, followed by a description of the methods used in the present study. The analysis then begins in Chapter 4 with a discussion of the context of these children’s lives, with a particular focus on poverty. Moving to the data from children themselves, Chapters 5 and 6 explore children’s inner lives and immediate relationships, specifically their emotions about parental incarceration and relationships with their parents. Chapters 7 and 8 pull back to reveal children’s interactions with their communities, and Chapter 9 widens the lens further to explore their experiences within the social policy context. Through a variety of empirical findings and by telling the story of parental incarceration in Canada from a critical and child-centred perspective, this thesis contributes to the scholarly understanding of parental incarceration

Characteristics of Web-based textual communications

Ankara : The Department of Computer Engineering and the Graduate School of Engineering and Science of Bilkent University 2012.Thesis (Ph. D.) -- Bilkent University, 2012.Includes bibliographical references.In this thesis, we analyze different aspects of Web-based textual communications and argue that all such communications share some common properties. In order to provide practical evidence for the validity of this argument, we focus on two common properties by examining these properties on various types of Web-based textual communications data. These properties are: All Web-based communications contain features attributable to their author and reciever; and all Web-based communications exhibit similar heavy tailed distributional properties. In order to provide practical proof for the validity of our claims, we provide three practical, real life research problems and exploit the proposed common properties of Web-based textual communications to find practical solutions to these problems. In this work, we first provide a feature-based result caching framework for real life search engines. To this end, we mined attributes from user queries in order to classify queries and estimate a quality metric for giving admission and eviction decisions for the query result cache. Second, we analyzed messages of an online chat server in order to predict user and mesage attributes. Our results show that several user- and message-based attributes can be predicted with significant occuracy using both chat message- and writing-style based features of the chat users. Third, we provide a parallel framework for in-memory construction of term partitioned inverted indexes. In this work, in order to minimize the total communication time between processors, we provide a bucketing scheme that is based on term-based distributional properties of Web page contents.Küçükyılmaz, TayfunPh.D