Syftet med studien var att undersöka hur litteraturen samt personer som arbetar med barn beskriver ärenden som innehåller en problembild som anknyter till Munchausen by proxy (MBP). MBP är en form av barnmisshandel där förövaren hittar på, framkallar eller överdriver symtom hos barnet. Materialet består av data från en litteraturstudie samt intervjuer med två personer. Metoden som använts för analys av materialet är meningskategorisering. Resultaten kopplades till de teoretiska begreppen anknytning och projektion. Studien visade att vissa beteenden hos föräldern är karaktäristiska då MBP förekommer. Det vanligast förekommande verkar vara förälderns benägenhet att söka vård för barnet samt den ihärdighet med vilken vården krävs. Vidare visar resultatet att samspelet mellan förälder och barn påverkas av att MBP förekommer. Förövaren kan agera som hon gör pga. bristande empati eller ilska. Barnets självuppfattning påverkas av samspelet mellan förälder och barn. Vissa orsaker till MBP kan relateras till föräldrarollen. Resultatet visar att framgångsrik behandling av förövare kräver ett erkännande av misshandeln. Resultatet visar på de starka känslor MBP väcker hos personer som arbetar med det. Det kan bero på föreställningar om förövarna som personalen har. Förövarna framställer sig som engagerade föräldrar och personalen känner sig lurad när MBP upptäcks.

Ett problem i välfärdsforskningen är att äldre individer ofta exkluderas från levnadsnivåundersökningarna genom en övre åldersgräns, alternativt inkluderas men utan att särskild hänsyn tas till de metodproblem som uppstår då respondenterna är äldre. Detta resulterar i bristande kunskap om de äldres levnadsförhållanden, hälsa och behov. Uppsatsens syfte är att belysa undersökningsdesignens betydelse för resultatet i levnadsnivåundersökningar av de allra äldsta. Tre för äldrestudier viktiga metodkomponenter diskuteras och analyseras: betydelsen av bortfall, exkluderingen av institutionsboende och användningen av indirekta intervjuer. Som underlag används datamaterial från Undersökningen om äldres levnadsvillkor (SWEOLD) från tre intervjuår, 1992, 2002 och 2004. SWEOLD är en nationellt representativ intervjubaserad levnadsnivåundersökning av de allra äldsta i Sverige. Genom jämförelser av olika undersökningsgruppers kön- och åldersstrukturer, relativa dödsrisker samt skillnader i olika hälso- och välfärdsmått analyseras och diskuteras effekten av olika undersökningsdesigner på resultaten. Resultaten av analyserna visar att om SWEOLD-studien antingen exkluderat institutionsboende eller valt bort att använda indirekta intervjuer skulle ca 20 procent av de äldre inte ha intervjuats, utöver bortfallet. Dessa grupper skiljer sig från svarandegruppen avseende ålders- och könsfördelning samt genom 3 gånger så hög relativ dödsrisk. Därmed skulle fler kvinnor, fler äldre och fler sjuka inte ha intervjuats och resultatet hade varit att andelen med problem inom områden som personlig omvårdnad (ADL), fysisk mobilitet och psykisk hälsa hade underskattats.

Partially restricting access to objects enables system designers to finely control the security of their systems. We propose a novel approach that allows granting partial access at method granularity on arbitrary objects to remote clients, using proxy objects. Our initial approach considers methods to be either safe (may be invoked by anyone) or unsafe (may be invoked only by trusted users). We next generalize this approach by supporting Role-Based Access Control (RBAC) for methods in objects. In our approach, a policy implementer annotates methods, interfaces, and classes with roles. Our system automatically creates proxy objects for each role, which contain only methods to which that role is authorized. This thesis explains the method annotation process, the semantics of annotations, how we derive proxy objects based on annotations, and how clients invoke methods via proxy objects. We present the advantages to our approach, and distinguish it from existing approaches to method-granularity access control. We provide detailed semantics of our system, in First Order Logic, to describe its operation. We have implemented our system in the Java programming language and evaluated its performance and usability. Proxy objects have minimal overhead: creation of a proxy object takes an order of magnitude less time than retrieving a reference to a remote object. Deriving the interface---a one-time cost---is on the same order as retrieval. We present empirical evidence of the effectiveness of our approach by discussing its application to software projects that range from thousands to hundreds of thousands of lines of code; even large software projects can be annotated in less than a day.

Social Cognitive Theory (SCT: Bandura, 1997) has been used successfully in understanding exercise adherence. To date, the majority of the exercise research has focused on situations of personal agency (i. e. , self as agent: e. g. , McAuley & Blissmer, 2000). However, there are a number of exercise situations in which people look to others to help them manage their exercise participation by enlisting a <i>proxy-agent</i> (Bandura, 1997). While using assistance from a proxy can promote the development of self-regulatory skills, Bandura (1997) cautions that reliance on a proxy actually reduces mastery experiences which can result in an inability to self-regulate one?s behaviour. Although research examined proxy-agency in exercise (e. g. , Bray et al. , 2001), the issue of reliance on the proxy at the expense of the participant?s ability to adjust to exercise without that agent has not been investigated. This potential dilemma of proxy-agency in exercise was at the core of this dissertation and was investigated in a series of three studies. Study 1 investigated whether those who differed in preferred level of proxy-contact also differed in their social-cognitions both within and outside a proxy-led exercise context. In addition, the relationships between proxy-efficacy, reliance and self-efficacy were examined. Results indicated that participants who preferred regular contact with an exercise proxy had lower self-regulatory efficacy, lower task efficacy, and weaker intentions in a proxy-led exercise context. Further, high-contact participants were shown to be less efficacious in dealing with the behavioural challenge of sudden class elimination. It was also demonstrated that higher reliance on the instructor was associated with lower self-efficacy and higher proxy-efficacy. Study 2 served to extend the findings of Study 1 through the examination of behavioural differences characteristic of differential levels of preferred proxy contact and the reasons for use of proxy-agency. It was found that exercise class participants preferring high contact with a proxy found exercising independently more difficult than did their low contact counterparts. It was also found that when faced with class elimination, those preferring high contact chose a self-managed activity alternative less frequently than did those preferring low contact. High contact participants also reported feeling less confident, less satisfied and perceived their alternative activity as more difficult than did those preferring low contact. In examining the reasons for preferring high proxy-contact, results indicated that a preference for high contact was associated with having had less experience exercising independently and allotting more responsibility for in-class participation to the class instructor as compared to preferring low proxy-contact. Study 3 used Lent and Lopez?s (2002) tripartite model of efficacy beliefs to examine the associations between relational efficacies (i. e. , other-efficacy and relation inferred self-efficacy (RISE) beliefs, proxy-efficacy) and various social cognitions relevant to proxy-agency. Results revealed that relational efficacies were distinct yet related constructs which additively predicted self-regulatory efficacy, satisfaction, intended intensity and reliance. Relational efficacies were also shown to make unique contributions to the predictions of the relevant social-cognitions. It was also demonstrated that RISE beliefs were associated with the attributions participants made. Specifically, higher RISE beliefs was associated with making more internal, personally controllable and stable attributions. These results represent the initial examination of relational efficacy beliefs in the exercise literature and provide additional evidence of the proxy-agency dilemma in exercise. Taken together, the present series of studies both support theorizing by Bandura on the dilemma of proxy-agency and represent an extension of the existing literature of proxy-agency in exercise. Results suggest that seemingly healthy, regularly exercising adults who choose to employ proxy-agency may be at risk for nonadherence in situations of behavioural challenge. The current findings have important implications for exercise leaders and interventionists as they must be aware of the balance between helping and hindering.

Partially restricting access to objects enables system designers to finely control the security of their systems. We propose a novel approach that allows granting partial access at method granularity on arbitrary objects to remote clients, using proxy objects. Our initial approach considers methods to be either safe (may be invoked by anyone) or unsafe (may be invoked only by trusted users). We next generalize this approach by supporting Role-Based Access Control (RBAC) for methods in objects. In our approach, a policy implementer annotates methods, interfaces, and classes with roles. Our system automatically creates proxy objects for each role, which contain only methods to which that role is authorized. This thesis explains the method annotation process, the semantics of annotations, how we derive proxy objects based on annotations, and how clients invoke methods via proxy objects. We present the advantages to our approach, and distinguish it from existing approaches to method-granularity access control. We provide detailed semantics of our system, in First Order Logic, to describe its operation. We have implemented our system in the Java programming language and evaluated its performance and usability. Proxy objects have minimal overhead: creation of a proxy object takes an order of magnitude less time than retrieving a reference to a remote object. Deriving the interface---a one-time cost---is on the same order as retrieval. We present empirical evidence of the effectiveness of our approach by discussing its application to software projects that range from thousands to hundreds of thousands of lines of code; even large software projects can be annotated in less than a day.

Web pages take noticeably longer to load when accessing the Internet using high-latency wide-area wireless networks like 3G. This delay can result in lower user satisfaction and lost revenue for web site operators. By locating a just-in-time prefetching push proxy in the Internet service provider's mobile network core and routing mobile client web requests through it, web page load times can be perceivably reduced. Our analysis and experimental results demonstrate that the use of a push proxy results in a much smaller dependency on the mobile-client-to-network latency than seen in environments where no proxy is used; in particular, only one full round trip from client to server is necessary regardless of the number of resources referenced by a web page. In addition, we find that the ideal location for a push proxy is close to the servers that the mobile client accesses, minimizing the latency between the proxy and the servers that the mobile client accesses through it; this is in contrast to traditional prefetching proxies that do not push prefetched items to the client, which are best deployed halfway between the client and the server.

The forwarding delay and throughput of a proxy server play significant role in the overall network performance. It is widely known that the forwarding delay of proxy¡¦s application layer is much larger than that of lower layers. This is because for a general purpose operating system, the receiving or sending data in application layer needs to move data through the TCP/IP stack and also cross the user/kernel protection boundaries. TCP Splice can forward data directly in TCP layer without going up to the application layer. This can be achieved by modifying the packet headers of one TCP connection from the original server to the proxy so that the TCP connection can be seamlessly connected to another TCP connection from the proxy to the client. To maintain the caching ability of proxy, TCP Tap can duplicate packets before they are forwarded by TCP Splice. The duplicated packets are copied into a tap buffer, so the application layer can read data from the tap buffer. We fully utilize the original TCP receive queue as the tap buffer and allow application layer to read data as usual. We chose Linux as the platform for experiment. The TCP Splice and Tap are implemented as Linux modules. Finally, we develop an HTTP proxy to test and verify our implementation. It is shown that the performance of proxy in terms of lower forwarding delay, higher throughput, and increased CPU utilization, can be improved significantly.

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Selenium (Se) is an essential trace element, which, with multiple oxidation states and six stable isotopes, has the potential to be a powerful paleo-environmental proxy. In this study, Se concentrations and isotopic compositions were analyzed in a suite of about 120 samples of fine-grained marine sedimentary rocks and sediments spanning the entire Phanerozoic. While the selenium concentrations vary greatly (0.22 to 72 ppm), the δ82/76Se values fall in a fairly narrow range from -1 to +1 , with the exception of laminated black shales from the New Albany Shale formation (Devonian), which have δ82/76Se values of up to +2.20 . Black Sea sediments (Holocene) and sedimentary rocks from the Alum Shale formation (Late Cambrian) have Se/TOC ratios and δ82/76Se values close to those found in modern marine plankton (1.72x10-6±1.55x10-7 mol/mol and 0.42±0.22 ). (Note: TOC = total organic carbon.) For the other sedimentary sequences, the Se/TOC ratios indicate enrichment in selenium relative to marine plankton. Additional input of isotopically light terrigenous Se (δ82/76Se ≈ -0.42 ) may explain the Se data measured in recent Arabian Sea sediments (Pleistocene). The very high Se concentrations in sedimentary sequences that include the Cenomanian-Turonian Ocean Anoxic Event (OAE) 2 possibly reflect a significantly enhanced input of volcanogenic Se to the oceans. As the latter has an isotopic composition (δ82/76Se ≈ 0 ) not greatly different from marine plankton, the volcanogenic source does not impart a distinct signature to the sedimentary Se isotope record. The lowest δ82/76Se values are observed in the OAE2 samples from Demerara Rise and Cape Verde Basin cores (δ82/76Se = -0.95 to 1.16 ) and are likely due to fractionation associated with microbial or chemical reduction of Se oxyanions in the euxinic water column. In contrast, a limiting availability of seawater Se during periods of increased organic matter burial is thought to be responsible for the elevated δ82/76Se values and low Se/TOC ratios in the black shales of the New Albany Shale formation. Overall, our results suggest that Se data may provide useful information on paleodepositional conditions, when included in a multi-proxy approach.

Significant portion of today’s internet traffic emerge from multimedia services. When coupled with growth in number of users accessing these services, there is tremendous increase in network traffic. CDNs aid in handling this traffic and offer reliable services by distributing content across different locations. The concept of virtualization transformed traditional data centers into flexible cloud infrastructure. With the advent of cloud computing technology, multimedia providers have scope for establishing CDN using network operator’s cloud environment. However, the main challenge while establishing such CDN is implementing a cost efficient and dynamic mechanism which guarantees good service quality to users. This thesis aims to develop, implement and assess the performance of a model that coordinates deployment of virtual servers in the cloud. A solution which dynamically spawns and releases virtual servers according to variations in user demand has been proposed. Cost-based heuristic algorithm is presented for deciding the placement of virtual servers in OpenStack based federated clouds. Further, the proposed model is implemented on XIFI cloud and its performance is measured. Results of the performance study indicate that virtual CDNs offer reliable and prompt services. With virtual CDNs, multimedia providers can regulate expenses and have greater level of flexibility for customizing the virtual servers deployed at different locations.