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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
81

”Säg inget till någon” : Skolsköterskans erfarenhet av attarbeta utifrån sekretess med elever itonåren. / ”Don't tell anyone” : The school nurse experience of workingon the basis of professional secrecy with adolscents

Artursson, Anna-Lena, Dolk, Marie January 2020 (has links)
Bakgrund: Skolsköterskans arbete omfattas av sekretess som är till för att skydda elevens integritet. Skolsköterskan behöver hantera sekretessen och bevara elevens integritet, samtidigt som arbetet kräver samverkan för att eleven ska få rätt stöd. Syfte: Studiens syfte var att belysa skolsköterskans erfarenheter av att arbeta utifrån sekretess med elever i tonåren. Metod: Kvalitativ metod med induktiv ansats. Semistrukturerade intervjuer med tre fokusgrupper analyserades enligt kvalitativ innehållsanalys. Resultat: Studien resulterade i tre huvudkategorier: hantera komplexa situationer och dilemman, avsätta tid för kommunikation och främja delaktighet, och finna stöd i situationen. Utöver kategorierna framkom temat viljan att göra gott och inte skada. Konklusion: Att arbeta utifrån sekretess innebär att skolsköterskan balanserar mellan att elevens självbestämmande och integritet bevaras och samtidigt samverka med andra. Det är en utmanande uppgift där den etiska principen viljan att göra gott och inte skada blir grundläggande för de beslut som tas. / Background: The school nurse's work is covered by professional secrecy in order to protect the student's integrity. School nurses need to manage the professional secrecy and maintain the adolscents integrity, while at the same time the work requires collaboration in order to receive the right support. Purpose: The aim of the study was to illuminate school nurse experience of working on the basis of professional secrecy with adolscents. Method: Qualitative method with an inductive approach. The result was achieved using a qualitative content analysis. Semi-structured interviews with three focus groups were conducted. Result: The study resulted in three main categories: dealing with complex situations and dilemmas, set aside time for communication and promote participation and find support in the situation. Besides the categories, a theme emerged: do good and no harm. Conclusion: Working on the basis of professional secrecy means the school nurse must balance the student's to self-determination and integrity while collaborating with others. It is a challenging task where the ethical principle wants to do good and not harm becomes fundamental to the decisions that are made.
82

Physical Layer Security With Active Jamming Using NOMA.

Polisetti, Mounika January 2021 (has links)
This paper is persuaded to understand the physical layer security in wireless commu-nications utilizing NOMA (Non Orthogonal Multiple Access) concepts in the presence of an eavesdropper. Physical layer security maintains the confidentiality and secrecyof the system against eavesdroppers. We use the power domain in this paper, where NOMA allows many users to share resources side by side. Power allocation concern-ing channel condition is taken into consideration where user whose channel condition is weak is allocated with eminent power to directly decode the signal, whereas theuser with better channel condition applies successive interference cancellation (SIC)to decode the signal. Here, the base station communicates with the users and sends data signals while the eavesdropper secretly eavesdrops on the confidential informa-tion simultaneously. In this thesis, to improve the physical layer security, jamming method was usedwhere users are assumed to be in full duplex, send jamming signals to degrade the performance of the eavesdropper. Analytic expressions of CDF, PDF, outage proba-bility and secrecy capacity are obtained from analyzing the NOMA jamming scheme. The numerical results are evaluated with the simulations results and analysed theeffect of jamming on improving the performance of the NOMA system in presenceof an eavesdropper.
83

La protection du renseignement britannique, américain et allemand pendant la Seconde Guerre mondiale. / The Protection of British, American and German Intelligence during World War II

De Witte Parra, Mona 09 December 2016 (has links)
Cette thèse est consacrée à l’étude de la protection des sources de renseignement britanniques pendant la Seconde Guerre mondiale, en enrichissant cette analyse grâce à des éléments de comparaison avec les pratiques privilégiées aux États-Unis et en Allemagne. Dans ces trois pays, des approches très différentes sont adoptées afin de s’assurer de la durabilité des sources et de pouvoir continuer à exploiter ces données précieuses, témoignant d’appréhensions variées de l’impératif de préserver ces sources et de politiques diverses à l’égard du choix complexe entre utilisation d’un renseignement et préservation de son origine, entre exploitation à court terme et bienfaits sur une échéance plus longue dans un contexte de guerre. En s’appuyant sur de nombreux documents d’archives civils et militaires des trois pays, cette étude présente leurs attitudes divergentes et permet de faire la lumière sur les véritables performances des services de renseignement des trois pays. Il est nécessaire de s’interroger sur le bien-fondé de la réputation de secret qui semble caractériser les agences britanniques, par opposition à leurs homologues américains, et sur le véritable succès des services allemands dans un pays marqué par de profondes divisions.Cette recherche détaille la coopération équivoque entre le Royaume-Uni et les États-Unis, qui a posé quelques-uns des premiers jalons de la « special relationship », la « relation spéciale » entre les deux pays, toute d’ambiguïté. Cette association est le théâtre de l’inversion du rapport de forces des deux puissances dans ce domaine comme dans bien d’autres. De plus, l’analyse des échanges des agences britanniques avec leurs homologues français et soviétiques permet d’adopter une nouvelle perspective dans l’étude de leurs relations internationales et de ces alliances complexes aux contours fluctuants. / This thesis investigates the protection of British intelligence sources during World War Two, and includes a comparison with American and German practices. In these three countries, intelligence officers adopted very different approaches to preserve these sources and to ensure that the latter could be used in the long term. Each country had a different perception of the balance between the immediate use of intelligence and the protection of its sources, between the short-term benefits and long-term preservation of these assets in the context of the war. Drawing on a vast amount of archival material, both civilian and military, this research presents these three countries’ various approaches and uses this analysis to reflect on their concrete achievements. This study interrogates the preconceived ideas about these countries’ intelligence practices, in particular the reputation of secrecy of the British agencies, as opposed to the lack of discretion of their American counterparts. Moreover, this thesis emphasises the particular situation of German secret services in a very divided country.The ambiguous cooperation between Britain and the United States during the Second World War helped pave the way for their « special relationship ». During the war, the balance of power between the two nations shifted dramatically, in the intelligence field as in many others. Moreover, the analysis of the exchanges between the British intelligence officers and their French and Soviet colleagues opens new research avenues in the study of their international relations and on these complex and fluctuating alliances.
84

Secure and efficient wireless communications in SWIPT-enabled cooperative networks

Hayajneh, Maymoona 14 April 2022 (has links)
Wireless communications has gone through tremendous growth in the past decades. There has been a shift in wireless network research from spectral efficiency and quality of service (QoS) constraints to energy efficiency and green communications to reduce power consumption. Green energy resources such as solar, wind, thermal and mechan- ical vibrations can be employed to increase the energy efficiency of energy-constrained networks such as wireless sensor networks. Converting the available energy in the sur- rounding area into electricity, energy harvesting (EH), has been the subject of recent research. EH from radio frequency (RF) signals can be utilized to prolong the lifetime of devices in energy-constrained systems. Wireless power transmission (WPT) for EH is a promising solution to provide a reliable source of energy for devices which are di cult to service due to mobility and/or hard to reach locations. The integration of relaying into conventional wireless networks is promising to increase the coverage area and reduce power consumption. However, the extra power consumed to relay signals may be a problem that can be mitigated by WPT. WPT has made it possible for relays to power themselves by capturing ambient energy wirelessly. The received signal at the relay can be utilized to both forward information and harvest energy. This dissertation focuses on practical energy harvesting schemes in wireless com- munication networks. Further, the broadcast nature of wireless systems makes wire- less transmissions more vulnerable to eavesdropping compared to wired signals. The goal of this work is to develop EH schemes that are capable of supplying sustainable energy to the relays and overcoming the secrecy hazards from potential eavesdroppers. Power splitting (PS) and time switching (TS) are studied in communication networks to prolong the lifetime of an energy-constrained relay. First, a dual hop system with an amplify and forward (AF) relay employing wireless information and power transfer (WIPT) via power splitting is studied. Optimal transmit antenna selection that max- imizes the end-to-end signal to noise ratio (SNR) at the destination is considered and the outage probability is derived. It is shown that the outage probability increases with the number of transmit antennas but this also increases the system complexity. Since the spectral efficiency with two-way relaying is higher than with one-way relaying, a two-way EH-based relay network with an eavesdropper is investigated. The secrecy capacity at the users is derived for two diversity combining cases at the eavesdropper, selection combining (SC) and maximal ratio combining (MRC). A friendly jammer is introduced to increase the secrecy capacity of the users by reducing the received signal to noise ratio at the eavesdropper since the signal of the jammer is considered as noise at the eavesdropper. The corresponding optimization problem is reformulated using the single condensation method (SCM) and geometric programming (GP) into a convex optimization problem. Then, GP is used to jointly optimize the power splitting factor of the relay and transmit powers of the two users and jammer to maximize the secrecy capacity of the system. Imperfect cancellation of the jamming signal at the relay is assumed. It is shown that increasing the power allocated to the jammer decreases the secrecy capacity at the users. However, when perfect jamming signal cancellation is assumed, increasing the power allocated to the jammer increases the secrecy capacity at the users. The secrecy capacity is also shown to be greater with a jammer than without a jammer. Channel state information uncertainty at the eavesdropper is also considered as an extra noise source. TS at the relay of a two-way EH-based relay network was also considered. GP is used to jointly optimize the time switching ratio of the relay and transmit powers of the two users and jammer to maximize the secrecy capacity of the system. It is shown that PS two-way relaying achieves a better secrecy capacity than TS two-way relaying. / Graduate
85

Secrecy Capacity of Cooperative Transmission with Opportunistic Relaying Scheme

Pasumarthi, Dhathri Pravallika January 2022 (has links)
The usage of wireless communication has increased over the past few years. Most wired communications are replaced by wireless communication for ease of use. Wireless communication transfers confidential information like personal information and credentials between two entities. We can't probably say that it is safe to send this information via wireless communication. As more data is sent, more attacks happen to steal the data. Hence, it is necessary to implement secure methods to transfer the data between source and receiver. In this communication channel, we use secrecy capacity as a parameter to measure how data is sent securely between source and destination. Generally, to achieve high system performance, the information is sent with low power, but this reduces the signal efficiency at the receiver. So, in this thesis, we have implemented cooperative transmission to increase the efficiency of low power signals by adding the relays between source and destination. This thesis consists of two relays. The relay that obtains the maximum signal-to-noise ratio is selected for the primary communication link. The other relay sends the signal to the eavesdropper to confuse the eavesdropper. In this thesis, we have derived the mathematical expression for SNR at receiver eavesdropper, and also we have derived a word for outage probability and secrecy capacity. Then, we simulated the Matlab code to obtain results on how the secrecy capacity affects by changing the various parameters like path loss exponent and fading severity parameter and suggests which environment is better to maintain high secrecy capacity. We also analysed the system performance and secrecy capacity in the presence of eavesdropper as well.
86

Anmälningsplikten till Socialtjänsten - En studie om skolpersonalens upplevelser av att göra en orosanmälan

Sternemar, Josefine, Mathisson, Denize January 2019 (has links)
Studien belyser den komplexa problematik som omsluter anmälningsplikten för skolpersonal vid misstanke eller kännedom om att ett barn far illa. Tidigare forskning pekar på att underrapportering är ett problem i de svenska skolorna, men samtidigt menar forskare på att anmälningsfrekvensen inte är intressant att undersöka om man inte också undersöker den problematik som lagstiftningen genererar. Studiens frågeställningar är därav utformade för att ta reda på hur skolpersonal upplever anmälningsplikten till Socialtjänsten enligt 14 kapitlet 1 § SoL, och hur deras syn på anmälningsplikten påverkas av att de inte kan anmäla sin oro anonymt. Studien söker även svar på hur grundskolors rutiner kring anmälningsförfarandet ser ut, och om skolpersonalen anser att något saknas i lagstiftningen eller från Socialtjänsten. För att få svar på frågeställningarna gjordes tre semistrukturerade intervjuer med totalt sju informanter som arbetar inom grundskolan i Malmö och Vellinge. Analysen bygger på utvecklingsekologi samt teorin om street-level bureaucracy, eller gräsrotsbyråkrati. De slutsatser som kunde dras efter studiens genomförande var att skolpersonalen upplever att den lagstadgade anmälningsplikten är något bra, och att deras anmälningsbenägenhet inte påverkas av det faktum att de inte kan anmäla anonymt. De upplever trots allt att anmälningsplikten genererar en viss utsatthet för dem som skolpersonal i kontakt med föräldrar. Samtliga skolor använde sig av konsultation med Socialtjänsten innan dess att en anmälan gjordes, och det fanns möjlighet till råd och stöd från elevhälsan både före och efter en anmälan. Det skolpersonalen saknade från lagstiftningen och Socialtjänsten var tydligare rutiner för Socialtjänsten när det kommer till att återkoppla till anmälaren. / The study highlights the complex issue surrounding school personnel’s duty to report to Social Services if they suspect or if it comes to knowledge that a child may be in physical, social or psychological danger. Previous research shows a lack of these reports in swedish schools, but at the same time researchers say that the frequency of reports is not relevant to study if one does not also study the problems that generates from the legislation itself. Therefore, this study’s questions at issue are designed to find out how the school personnel experience the duty to report concern for a child to Social Services, and in which way their experience is affected by the fact that they can not report anonymously. The study also investigates the schools’ routines for making these reports, and if the school personnel feel that something is missing from the legislation or the Social Services regarding the duty to report concern for a child. In order to answer these questions, three semi-structured interviews with a total of seven informants from three different schools in Malmö and Vellinge were conducted. The analysis is based ecological systems theory and the theory of street-level bureaucracy. The final conclusions were that the school personnel has a positive attitude towards the duty to report, and that their tendency to report is not affected by the fact that they can not report anonymously. They do however experience an exposure generated from the duty to report, when it comes to the parents’ reactions. All schools used the opportunity to consult with Social Services before making a report, and they all had the opportunity to get help and support from the student health before and after making a report. What they felt were missing in the legislation was a more clear demands for Social Services to give feedback to the reporter.
87

A Wind River Romance

Leigh, Megan Breen 01 January 2010 (has links)
A first-person narrative adult novel explores the theme of abandonment with its residual and enduring effects, and its antithetical theme of loyalty that is continually tested and measured. The protagonist, editor of the local newspaper in a small, isolated agricultural community in the mid-1960s, provides the narrative nexus of two families. His is a community which is a mix of characters that are quirky by virtue of their natures or the remote circumstances of their existence. Both families in focus have treasure troves of secrets. Only after the appearance of a mysterious young woman and her subsequent murder do the tightly bound secrets of the families and the larger community begin to unravel. The narrator reveals his personal story as it relates to how he reacts and responds to the events at hand. Adding to his personal experience in the community, the narrator offers texture and enhancement to the story through archived newspaper articles and his interpretation of short silent movie reels chronicling the town's history from its earliest days until the end of World War II. Characters from within and without the community assume disguises to maintain their lifestyle or achieve a nefarious purpose while other characters hide behind the falsehoods of their comfortable, everyday lives. The one honest character becomes a victim of his own purity, despite attempts of the narrator to intervene. Not until forty years after the events that changed so many lives is it safe for the truth to bubble to the surface.
88

Enhancing Secrecy via Exploring Randomness in the Wireless Physical Layer

Talat, Rehan 01 January 2013 (has links) (PDF)
In order to establish a secure connections in the wireless environment, cryptographic methods may require an exchange of a key or secret. Fortunately, the environment provides randomness due to multi-path fading that can be exploited by physical-layer security algorithms to help establish this shared secret. However, in some cases, multi-path fading might be absent or negligible; therefore, we look for artificial ways to increase randomness. In this thesis, we explore antenna radiation variation by altering the phase between two antennas as a means of creating artificial fading. We construct a model of the antenna gain variation by analyzing the radiation pattern and run Monte-Carlo simulations to compare our approach to a base case with only multi-path fading. We then empirically collect data in order to confirm our analysis. Finally, we incorporate this model in a prominent security algorithm to demonstrate the improvements in security possible through such an approach.
89

A Moderated-Mediation Model of Pay Secrecy

Berger, Julia Lizabeth 18 December 2013 (has links)
No description available.
90

Optimal Power Allocation and Secrecy Capacity of The Full-Duplex Amplify-and-Forward Wire-tap Relay Channel Under Residual Self-Interference

Dang, Cuong Hung January 2015 (has links)
No description available.

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