Privacy enhancing technologies have proven to be a beneficial area of research lessening the threats users' privacy in centralised systems such as online social networks. Decentralised solutions have been proposed to extend the control that users have over their data as opposed to the centralised massive collection of personal and sensitive data. The power that the service provider has in centralised systems has been shown to diminish the user’s privacy. Moreover, the disclosures in 2013 of a global surveillance program in collaboration with some of the service providers of such centralised systems have accelerated the debate on how to take action to counteract the threats to privacy. Privacy-preserving decentralised systems are plausible solutions to such threats. However, the removal of the central authority comes with two main trade-offs, mimicking the features and taking over the supervision of the security and privacy threats that were a responsibility of the central authority. In our thesis, we propose the use of privacy-preserving decentralised systems and develop three solutions in terms of decentralisation, functionality, and achievable security and privacy. For decentralised systems we show a mechanism for user authentication via standard credentials. Within the realm of decentralised online social networks we implement a coordination and cooperation mechanism to organise events without the need of a trusted third party. Finally, we improve one of the aspects of the user’s privacy: anonymity, by showing an implementation of a privacy-preserving system to submit and grade documents anonymously in systems where the central authority is still required. Our solutions are some concrete examples of how privacy as data control can be achieved to varying degrees. Nonetheless, we hope that the protocols we propose and the evaluation of the security and privacy properties can be useful in other scenarios to mitigate the diverse dangers to personal privacy. / Integritets främjande teknik — på engelska, privacy enhancing technologies — har visat sig vara ett positivt forskningsområde som syftar till att minska hoten mot den personliga integriteten av användarnas personuppgifter i centraliserade informationssystem som online sociala nätverk — på engelska, online social networks. Följaktligen har decentraliserade lösningar föreslagits för att förlänga den kontroll som användare har över sina data i motsats till en centraliserade massiv samling av personliga och känsliga data. Den kraft som tjänsteleverantören har i centrala informationssystem har visat sig minska användarens integritet vid fall av missbruk, censur eller dataläckage. Vidare har upplysningarna 2013 av ett globalt övervakningsprogram som leds av offentliga efterlysningsinstitutioner i samarbete med några av tjänsteleverantörerna av sådana centraliserade informationssystem påskyndat debatten om hur man vidtar åtgärder för att motverka hot mot integritet. I synnerhet hotet mot den lagliga "rätten att bli ensam" — på engelska, "right to be let alone", som definierats av Samuel Warren och Louis Brandeis år 1890 i sin inflytelserika laggransknings artikel "The Right to Privacy". Sekretessskyddande decentraliserade system är trovärdiga lösningar på sådana hot och ett av de vanligaste alternativen som åtgärdas idag. Avlägsnandet av den centrala auktoriteten kommer emellertid med två huvudsakliga kompromisser, efterlikna funktionerna i det centraliserade informationssystemet på ett användbart sätt och överta övervakningen av säkerhets och hoten som en gång var ett centralt ansvar för centralt auktoritet. I vår avhandling använder vi decentraliserade system för integritetsskydd och utvecklar tre lösningar för centraliserade informationssystem när det gäller decentralisering, funktionalitet och uppnåelig säkerhet och integritet. I decentraliserade informationssystem generellt visar vi på en konkret mekanism för användarautentisering via standard användar-lösenordsuppgifter med jämförbar användbarhet för standardiserade centraliserade applikationer. Inom ramen för praktiska decentraliserade system visar vi på ett specifikt exempel på domänen för decentraliserade online sociala nätverk — på engelska, decentralised online social networks — som implementerar en samordnings- och samarbetsmekanism för att organisera händelser utan att behöva ha en betrodd tredje part. Slutligen går vi tillbaka till de centraliserade systemen där närvaron av den centrala myndigheten fortfarande krävs och i stället förbättrar en av aspekterna av användarens integritet: anonymitet genom att visa en implementering av ett system för att skicka in och klassificera dokument anonymt i akademisk sfär i ett generiskt centraliserat system för integritetsskydd. Våra lösningar är några konkreta exempel på hur integritet som datakontroll, som det paradigm som Anita Allen förutser, kan uppnås i varierande grad i centraliserade och decentraliserade informationssystem för integritetsskydd. Ändå hoppas vi att de integritetsskydd protokollen som vi föreslår och utvärderingen av säkerhets- och sekretessegenskaperna kan vara användbara i andra scenarier för att mildra de olika farorna för personlig integritet som vi står inför för närvarande. / Las tecnologías para mejorar la privacidad — en inglés, privacy enhancing technologies — han demostrado ser una beneficiosa área de investigación para disminuir las amenazas a la privacidad de la información personal de los usuarios en sistemas de información centralizados como las redes sociales on line — en inglés, online social networks. Por ello, se han propuesto soluciones descentralizadas para ampliar el control que los usuarios ejercen sobre sus datos en contraposición a la recogida de datos personales y sensibles en sistemas centralizados. Casos de mal uso, censura o incluso fuga de datos demuestran que el poder del proveedor de servicios en sistemas de información centralizados disminuye la privacidad del usuario. Las revelaciones en 2013 de un programa de vigilancia a nivel global dirigido por agencias de inteligencia públicas en colaboración con algunos de los proveedores de servicios de sistemas de información centralizados han acelerado el debate sobre las medidas a tomar para contrarrestar las amenazas a la privacidad. En particular, la amenaza al "derecho a la soledad" — en inglés, "right to be let alone"— enunciado por Samuel Warren y Louis Brandeis en 1890 en el influyente artículo legal, "El derecho a la intimidad". Los sistemas descentralizados que preservan la privacidad son soluciones viables ante las amenazas a la privacidad, y una de las alternativas más comunes en la actualidad. Sin embargo, la supresión de la autoridad central conlleva tratar de resolver dos inconvenientes: replicar la funcionalidad de los sistemas de información centralizados de forma que sean utilizables y asumir la vigilancia de las amenazas a la seguridad y privacidad que anteriormente eran responsabilidad de la autoridad central. En esta tesis, se propone el uso de sistemas descentralizados que preservan la privacidad y para ello desarrollamos tres soluciones a los sistemas de información centralizados desde los puntos de vista de descentralización, fun- cionalidad y, seguridad y privacidad. En los sistemas de información descentralizados, diseñamos un mecanismo de autenticación de usuarios mediante el uso de credenciales estándar usuario-contraseña cuya usabilidad es comparable a las aplicaciones en sistemas centralizados. En el ámbito más práctico de los sistemas descentralizados mostramos un ejemplo específico en el área de las redes sociales on line descentralizadas — en inglés, decentralised online social networks — implementando un mecanismo de coordinación y cooperación para la organización de eventos sin necesidad de existencia de un tercero de confianza. Finalmente, en los sistemas de información centralizados, en los que la presencia de una autoridad central sigue siendo necesaria, intentamos mejorar uno de los aspectos de la privacidad del usuario: el anonimato, diseñando e implementando un sistema para presentar y evaluar documentos de forma anónima en el ámbito académico en un sistema de información genérico y centralizado. Las soluciones que proponemos son algunos ejemplos concretos del concepto de "privacidad como control de datos" — en inglés, "privacy as data control"— tal y como lo definió Anita Allen. Un paradigma que se puede conseguir en diversos niveles tanto en sistemas de información centralizados como descentralizados. No obstante, deseamos que los protocolos para preservar la privacidad que proponemos junto con la evaluación de las propiedades de seguridad y privacidad sean de utilidad en otros ámbitos para contribuir a mitigar las diversas amenazas a la privacidad a las que no enfrentamos en la actualidad. / <p>QC 20170508</p><p></p> / PeerSoN: Privacy-Preserving P2P Social Networks

It is recognised that gender equality and diversity are essential for building successful organisations. To tackle the global challenges characterised by economies today, one must ensure equal opportunities for all, both men and women. Organisations have acknowledged the benefits of a more gender equal workforce and are starting to take action. But what are the results of such actions? We have found that a lot of research is focused on the sources of gender inequality in organisations but little on the efficacy of different actions to counter those inequalities. The purpose of this thesis is to examine how active gender equality work can impact an organisation. A case study of an organisation in the IT consultancy industry in Sweden is carried out where active gender equality work has been initiated through the internal project “the Gender Equality Project”. Empirical data gathered from interviews with employees from all levels of the organisation has been the main source of data collection and has worked as a base for the analysis and discussion. The research question that have guided our work is: How can active gender equality work impact the structure and culture within an organisation in a male-dominated industry? This thesis is based on a subjective approach, assuming that reality can be seen as a social construction and that humans create their own reality. This implies that the social world is viewed as a process which is created and recreated everyday through the usage of language, routines and actions. Further, this thesis argues that organisations should be seen as gendered and that assumptions about gender underlie the construction of organisations, resulting in a marginalisation of women which contributes to the maintenance of gender segregation in organisations. The findings show that active work with gender equality has resulted in structural and cultural impacts in several areas, such as more gender aware recruitment processes and external communication strategies as well as a culture which encourages employees to call out biases and defend gender equality initiatives. The findings also reveal an organisational structure which partly counteract the effects of gender equality work and a deficient communication of the purpose of the project which, currently, prevents it from becoming institutionalised. Much emphasis is put on the many middle managers in the organisation to bring the project forward and continue working with it, without clear expectations and guidance from the top management which has resulted in a halt and an inaction from the middle managers. / Jämställdhet och mångfald anses som essentiellt för att bygga framgångsrika organisationer. För att kunna tackla de globala utmaningarna som världen står inför, måste lika möjligheter för både kvinnor och män kunna säkerställas. Fler och fler organisationer bekräftar fördelarna med en mer jämställd arbetskraft och börjar arbeta mot förändring. Men vad är resultatet av sådant arbete? Vi har funnit att tidigare forskning tenderar att fokusera på orsakerna till ojämställdhet i organisationer, istället för den verkan olika initiativ och arbete för att främja jämställdhet har. Uppsatsens syfte är att utvärdera hur aktivt jämställdhetsarbete kan påverka en organisation. En fallstudie har genomförts på en svensk organisation verksam inom IT-konsultbranschen, där aktivt jämställdhetsarbete har initierats genom ett internt projekt kallat “Jämställdhetsprojektet”. Den främsta källan till empirisk data härrör från intervjuer med anställda på alla nivåer i organisationen och denna data har lagt grunden för analys och diskussion. Den forskningsfråga som guidat oss i vårt arbete är följande: Hur kan aktivt jämställdhetsarbete påverka strukturen och kulturen i en organisation i en mansdominerad bransch? Uppsatsen tar en subjektiv ansats, och utgår från att verkligheten ses som en social konstruktion och att människor skapar sin egen verklighet. Detta medför att den sociala världen ses som en process som skapas och återskapas varje dag genom språkbruk, rutiner och handlingar. Vidare argumenteras det för att organisationer ska ses som könade och att antaganden om kön ligger till grund för konstruktionen av organisationer. Detta medför en marginalisering av kvinnor vilket bidrar till ett upprätthållande av könssegregeringen i organisationer. Resultaten visar att aktivt jämställdhetsarbete resulterar i strukturella och kulturella effekter. Effekterna kan ses genom en mer genusmedveten rekryteringsprocess och strategier för extern kommunikation men även en kultur där anställda uppmuntras till att uppmärksamma och motarbeta fördomar och försvara initiativ för jämställdhet. Resultaten belyser även en organisationsstruktur som till viss del motverkar effekterna av aktivt jämställdhetsarbete och en bristande kommunikation av projektets syfte, vilket i dagsläget hindrar en institutionalisering. Stor vikt läggs på organisationens mellanchefer att driva projektet framåt och fortsätta dess arbete. Det saknas dock klara förväntningar och vägledning från koncernledningen, vilket har resulterat i en stagnering och passivitet från organisationens mellanchefer.

The concept of Web3 is increasingly entering into mainstream discourses. With many terming 2021 the ‘year of NFTs’ (non-fungible tokens), 2022 has been labelled as the ‘year of DAOs’ within the Web3 ecosystem. Decentralised autonomous organisations (DAOs) are groups that come together as a result of a specific purpose or interest and pursue their collective goals through leveraging Web3 technologies and governing over a shared treasury. Curious about these trends, I joined a community with a music, creative expression, and culture focus which had plans to become a DAO. A few months into being a member of this community, I was hired to join the community’s Core Team. While there have been a few articles published on the topic of DAOs, none focus specifically on what members of these DAOs value and how these priorities change over time. Utilising my unique perspective of being deeply involved in a DAO as a Core Team member, this thesis addresses this gap through an autoethnographic analysis of the shifting priorities of the most active members over the course of ten months within the first year of the community/ DAO being established. Bourdieu’s lens of different types of capital, together with a more modern extension of e-capital, and field theory are applied. The analysis reveals trends in the types of capital that are most valued during different phases of development of the community/ DAO being examined and how these are linked to specific milestone events that occur.

A quantitative, descriptive, explorative design was used to evaluate a decentralised primary health care training programme at a training unit in the Limpopo Province. The study sought to determine to what extent the newly qualified diplomates were able to manage patients appropriately when faced with the realities, such as the shortage of personnel, large numbers of patients, shortage of resources and time constraints in the real situation without the support and guidance from medical practitioners and senior nursing personnel. Data were collected by observing the diplomates as they managed patients with hypertension by making use of checklists. The diplomates were also interviewed by making use of an in interview schedule. The major inferences drawn from this study was that these diplomates were competent in the management of these patients and were satisfied with their abilities and training. / Health Studies / M. A. (Health Studies)

The novel contribution of the thesis is the design and implementation of decentralised output feedback power system controllers for power oscillation damping (POD) over the entire operating regime of the power system. The POD controllers are designed for the linearised models of the nonlinear power system dynamics. The linearised models are combined and treated as parameter varying switched systems. The thesis contains novel results for the controller design, bumpless switching and stability analysis of such switched systems. Use of switched controllers against the present trend of having single controller helps to reduce the conservatism and to increase the uncertainty handling capability of the power system controller design. Minimax-LQG control design method is used for the controller design. Minimax-LQG control combines the advantages of both LQG and H control methods with respect to robustness and the inclusion of uncertainty and noise in the controller design. Also, minimax-LQG control allows the use of multiple integral quadratic constraints to bound the different types of uncertainties in the power system application. During switching between controllers, switching stability of the system is guaranteed by constraining the minimum time between two consecutive switchings. An expression is developed to compute the minimum time required between switchings including the effect of jumps in the states. Bumpless switching scheme is used to minimise the switching transients which occur when the controllers are switched. Another contribution of the thesis is to include the effect of on load tap changing transformers in the power system controller design. A simplified power system model linking generator and tap changing transformer dynamics is developed for this purpose and included in the controller design. The performance of the proposed linear controllers are validated by nonlinear computer simulations and through real time digital simulations. The designed controllers improve power system damping and provide uniform performance over the entire operating regime of the generator.

Sensor networks are being used in several emerging applications not even imagined some years ago due to advances in sensing, computing, and communication techniques. However, these advances also pose various challenges that must be faced. One important challenge is related to the autonomous capability needed to setup and adapt the networks, which decentralizes the control of the network, saving communication and energy resources. Middleware technology helps in addressing this kind of problem, but there is still a need for additional solutions, particularly considering dynamic changes in users' requirements and operation conditions. This paper presents an agent-based framework acting as an integral part of a middleware to support autonomous setup and adaptation of sensor networks. It adds interoperability among heterogeneous nodes in the network, by means of autonomous behavior and reasoning. These features also address the needs for system setup and adaptations in the network, reducing the communication overhead and decentralizing the decision making mechanism. Additionally, preliminary results are also presented.

Ricefield based fish seed production (RBFSP) in irrigated spring (boro) ricefields after initial introductions by external promoters has spread among farmers in parts of Northwest Bangladesh. This approach to producing juvenile fish, rather than by specialised geographically clustered hatchery and nursery enterprises, has been recognised as a strategy for decentralised production that makes large high quality seed available locally and supports food fish production. RBFSP has been promoted by the international NGO CARE as part of a process to improve rice-based livelihoods of farming households using a farmer field school (FFS) approach in two consecutive projects between 1993 and 2005. The approach is technically simple and is based on the stocking of common carp (Cyprinus carpio) eggs and Nile tilapia (Oreochromis niloticus) broodfish in ricefields. As a new approach to farmer level fish seed production, its livelihood impacts on the farming households as well as associated actors; its adoption, adaptation and rejection process in farming households; and its cost-effectives for dissemination at farmer level were not well understood. This thesis mainly applies the concept of the sustainable livelihood approach (SLA) using tools and processes of the growing family of participatory research. A systems approach was used to ensure that the key stakeholders including households, community and extension organizations were included. The study was initiated with a well-being analysis of community households to identify poorer households before exploring impacts of RBFSP on poorer producing households (RF) compared to non-producing (NRF) households based on one-off and longitudinal surveys. Livelihoods impacts on other actors linked directly and indirectly with RBFSP were also investigated. The adoption process of RBFSP at the household level and the cost-effectiveness of its promotion were assessed. Impact studies at the household level showed that RF households were significantly larger and had lower levels of formal education than NRF. Adoption of RBFSP had improved practical skills and hence substantially improved human capital in RF households. RF households tended to have more of their ricefish plots located adjacent to their households. Poor and intermediate adopters had smaller riceplots than better-off households but higher seed production efficiencies (poor-315.1 kg fingerlings/ha; intermediate-419.1 kg fingerlings/ha) than better-off households (294.6 kg fingerlings/ha). In addition to direct consumption of large fingerlings, RF households restocked them for further growth in their household ponds in doing so increasing yields by 60%. Fish consumption increased substantially in RF households based on their own production reducing their dependency on purchase from markets. The year round longitudinal survey revealed that activities for RBFSP were compatible with their existing rice-based agriculture activities for household members including men, women and children. The relatively limited income from fingerling production improved cash flow in the low income months. Consumption of large size fingerlings from ricefields provided nutrient dense food in the ‘hungry gap’ months when supplies of wild fish were poor, smoothing consumption. Apart from RF households, RBFSP extended its livelihoods impacts to a wide range of actors in and around the seed producing community. Poor fry traders were found to be key actors in the spread and support of RBFSP. On average fry traders supplied fingerlings to 35 foodfish producers within a mean distance of 5 Km from producing households in a community where RBFSP was well established. The end users (foodfish producers) included households with their own ponds, ponds with multiple ownership and larger waterbodies leased by small groups. Locally available RFBSP juveniles were attractive to each of these groups, supplementing hatchery derived seed. A large number of complex socio-cultural and technical factors were related to household level adoption of RBFSP. The major factors included use of cash generated to prevent distress sales of rice; lack of requirement to use pesticide in ricefields; meeting the household consumption demand; capacity to restock fingerlings in ponds; lack of any negative effects on rice production; increased non-stocked fish production in riceplots; simplicity of the technology; ease of fish harvest from riceplots; increased ability to gift fingerlings/foodfish to relatives and neighbours; more efficient use of both riceplot and irrigation pumps. The most important reasons for households not attempting or quickly rejecting RBFSP were labour conflicts with other activities. However, lost access to the riceplots through changes in tenure was the most common cause of late rejection by households who had practiced RBFSP for several years after withdrawal of CARE support. Location of fish seed producing plots close to the homesteads facilitated household women to contribute to seed production activities through feeding and looking after fish. Women were able to decide and control resources generated from fingerling sales as well as choosing to gift fingerlings to their relatives. Informal transfer of fingerlings in this way stimulated spread of RBFSP. Decentralised fish seed production was promoted through FFS very cost effectively. The introduction of an improved strain of Nile tilapia (GIFT) broodfish greatly enhanced the returns from decentralised seed production based on common carp alone. High levels of secondary adoption improved benefits from promoting RBFSP. The major benefit derived from the improved returns to food fish farmers using locally produced seed. Higher levels of net present value (NPV) and benefit cost ratio (BCR) were achieved based on promotion of mixed-sex tilapia in RBFSP than mono-sex tilapia produced in a large scale central hatchery. Cost-effectiveness in terms of multiplier development impacts on ramification of secondary adopters and, income of fry traders and foodfish producers, RBFSP also showed better performance than a mono-sex tilapia hatchery.

A quantitative, descriptive, explorative design was used to evaluate a decentralised primary health care training programme at a training unit in the Limpopo Province. The study sought to determine to what extent the newly qualified diplomates were able to manage patients appropriately when faced with the realities, such as the shortage of personnel, large numbers of patients, shortage of resources and time constraints in the real situation without the support and guidance from medical practitioners and senior nursing personnel. Data were collected by observing the diplomates as they managed patients with hypertension by making use of checklists. The diplomates were also interviewed by making use of an in interview schedule. The major inferences drawn from this study was that these diplomates were competent in the management of these patients and were satisfied with their abilities and training. / Health Studies / M. A. (Health Studies)

Modern science relies on workflow technology to capture, process, and analyse data obtained from scientific instruments. Scientific workflows are precise descriptions of experiments in which multiple computational tasks are coordinated based on the dataflows between them. Orchestrating scientific workflows presents a significant research challenge: they are typically executed in a manner such that all data pass through a centralised computer server known as the engine, which causes unnecessary network traffic that leads to a performance bottleneck. These workflows are commonly composed of services that perform computation over geographically distributed resources, and involve the management of dataflows between them. Centralised orchestration is clearly not a scalable approach for coordinating services dispersed across distant geographical locations. This thesis presents a scalable decentralised service-oriented orchestration system that relies on a high-level data coordination language for the specification and execution of workflows. This system's architecture consists of distributed engines, each of which is responsible for executing part of the overall workflow. It exploits parallelism in the workflow by decomposing it into smaller sub-workflows, and determines the most appropriate engines to execute them using computation placement analysis. This permits the workflow logic to be distributed closer to the services providing the data for execution, which reduces the overall data transfer in the workflow and improves its execution time. This thesis provides an evaluation of the presented system which concludes that decentralised orchestration provides scalability benefits over centralised orchestration, and improves the overall performance of executing a service-oriented workflow.

Content of this master`s thesis is theoretical introduction of the power factor, reactive power and voltage control of decentralised sources of the high voltage in the E.ON distribution network. Furthermore, the thesis deals with possibilities of regulating the power factor and reactive power, carried on above-mentioned resources, in other to stabilize the voltage and overflow control of the reactive power to higher voltage level. The practical part describes how the automatic power factor and voltage control had been put into action by central management control within the headquaters dispatching systém of the company. Following chapter acquaints a reader with information of how the automatic power factor and voltage control had been tested and how it is utilized in practice. In the conclusion the work summarizes results and effects of the power factor regulation and voltage control to stabilize the voltage and the overflow of the reactive power in the E.ON network.