30 research outputs found

    Universally Composable Verifiable Random Oracles

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    Random Oracles werden häufig in der Kryptographie eingesetzt um sehr effiziente Instanziierungen mächtiger kryptographischer Primitive zu konstruieren. Jedoch ist diese Praxis im Allgemeinen nicht zulässig wie verschiedene Nicht-Instanziierungs-Ergebnisse für Random Oracles mittels lokal berechenbarer Familien von Funktionen durch Halevi et al. (JACM ’04) zeigt. Die Random Oracle Modell kann sicher eingesetzt werden, indem Random Oracles nicht mit einer lokal berechenbaren Hashfunktion, sondern stattdessen mit einem interaktiven Protokoll instanziiert werden. In der realen Welt könnte solch ein interaktives Protokoll beispielsweise aus einem vertrauenswürdigen Server, welcher über das Internet erreichbar ist, bestehen. Dieser Server würde sodann eine der bekannten Techniken wie lazy sampling oder das Auswerten einer Pseudo-Zufälligen Funktion verwenden, um die Funktionalität eines Random Oracle bereitzustellen. Ein klarer Nachteil dieses Ansatzes ist die große Menge an Interaktion, die bei jeder Berechnung, die eine Auswertung des Random Oracle beinhaltet, nötig ist. Wir wollen diese Interaktion auf ein Minimum reduzieren. Um obiges Unmöglichkeitsresultat zu umgehen, muss die Auswertung des Random Oracle auf einer frischen Eingabe Interaktion der auswertenden Partei mit einer anderen Partei beinhalten. Dies ist jedoch nicht der einzige Verwendungszweck von Random Oracles, der häufig in kryptographischen Protokollen auftritt. Bei einem weiteren solchen Zweck wertet zunächst eine Partei A das Orakel auf einer Eingabe aus und erhält einen Hashwert. Im Anschluss sendet A Eingabe und Ausgabe (im Kontext eines Protokolls) an eine zweite Partei B und möchte B davon überzeugen, dass das Random Oracle korrekt ausgewertet wurde. Eine einfache Möglichkeit dies zu prüfen besteht darin, dass B selbst eine Auswertung des Random Oracle auf der erhaltenen Eingabe tätigt und die beiden Ausgaben vergleicht. In unserem Kontext benötigt dies jedoch erneut Interaktion. Der Wunsch diesen zweiten Verwendungszweck nicht-interaktiv zu machen führt uns zum Begriff eines Verifiable Random Oracle (VRO) als Erweiterung eines Random Oracle. Abstrakt besteht ein VRO aus zwei Orakeln. Das erste Orakel verhält sich wie ein Random Oracle dessen Ausgabe um einen Korrektheitsbeweis erweitert wurde. Mit Hilfe dieses Beweises kann das zweite Orakel dazu verwendet werden öffentlich die korrekte Auswertung des Random Oracle zu verifizieren. Obwohl diese Orakel-basierte Formulierung nicht notwendigerweise nicht-interaktive Verifikation besitzt, so erlaubt jedoch die Einführung expliziter Korrektheitsbeweise dies. In dieser Masterarbeit formalisieren wir zunächst den Begriff eines VRO im Universal Composability Framework von Canetti (FOCS ’01). Danach wenden wir VROs auf zwei kryptographische Anwendungen an, die in ihrer ursprünglichen Formulierung das Random Oracle Modell verwenden, und zeigen, das deren Sicherheitseigenschaften erhalten bleiben. Um zu zeigen, dass unsere Definition realisierbar ist, konstruieren wir mehrere Protokolle, die die ideale VRO Funktionalität realisieren. Diese reichen von Protokollen für eine einzelne vertrauenswürdige Partei bis hin zu verteilten Protokollen, die eine gewisse Menge an böswilliger Korruption erlauben. Wir vergleichen weiterhin VROs mit ähnlichen existierenden Primitiven

    POLITENESS PRINCIPLE: PRESIDENT JOKO WIDODO'S SPEECH ACT IN VIDEO BLOG

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    ABSTRACT The aim of the research is analyzing the utterances of Mr. Joko Widodo as president of Indonesia with vloggers. In this study, the writer analyzes the rules of president conducting his utterances at vloggers’ vlogs. The vlogs taken from skinnyindonesian24 which has 1.3M subscribers and Arif Muhammad which has 1.5M subscribers (data per November 25, 2018). The data taken and analyzed both qualitative and quantitative data. The elaboration of the methods used to measure language politeness, to count the data whether politenes or not. The data taken from Arif Muhammad’s vlog (1.596.033 subscribers) which entitle  Ngevlog bareng Presiden and SkinnyIndonesian24 were created by brothers Andovi da Lopez and Jovial da Lopez’s vlogwho have 1.344.548 subscribers entitleHow to Become a President. The result of this research imply both of the vlogs Mr. Joko Widodo applies politeness strategies even in informal situation both vlogs. He acts extraordinary pragmatic forces and high politeness. So that, the audience gets the emotion, sympathy and persuasion of those who watches of them at vlog.  Keywords: politeness principal, speech acts, vlog, pragmatic

    Lived Experiences of Young Adults From Broken Families on Marital Relationships

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    People often take for granted the impact of having separated parents on children. Individualsfrom broken homes are highly impressionable and the effects of what they have witnessedduring childhood are conventionally carried with them into adulthood. There have been alimited amount of studies describing the impact of parental separation of young adults’perception on marriage. This study aimed to delve into how parental separation affects youngadults’ perception on marital relationship. Specifically, this study deals with the perception onmarital relationships of young adults from broken families. Also, it explores the outlook onmarital relationships of young adults from broken families after their parents’ separation. Thisstudy used a phenomenological research design to explore young adults’ perception onmarriage. A total of 12 young adults coming from broken families participated in the study toprovide the researchers with information about their thoughts and feelings about marriage. Theresearchers used a semi-structured interview and the collected data were analyzed using theColaizzi’s method. On the perception on marital relationship of young adults from brokenfamilies, four themes emerged, namely: God-centered relationship; couples in love;legalization of a relationship; and foundation of family. The participants defined that perceptionof marital relationships is related to the definition of a healthy relationship between husbandand wife. Furthermore, the factors that affect the outlook of young adults from broken familieswere categorized into four themes: negative experience leading to fear, development of trustissues, poor self-worth, and attachment problems. Here, the participants explained that thenegative outlook on marital relationships is related to the negative experiences, trust issues,poor self-worth, and attachment issues that developed as impact of broken families. Theresearchers recommend that similar studies with a quantitative approach be conducted for thefurther assessment of the dilemma presented by the study. Further research could bring aboutdifferent results especially if done on a large population and different

    Recovery and sense of self for individuals with a borderline personality disorder diagnosis

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    Recovery for individuals diagnosed with Borderline Personality Disorder (BPD) is a complex, multifaceted process that remains under researched. The thesis focuses on two elements of recovery for individuals with a BPD diagnosis; elements of mental health services that individuals find therapeutically valuable, and how the concept of recovery affects sense of self. The literature review is a thematic synthesis of therapeutic and non-therapeutic elements of mental health care services for those with a BPD diagnosis and provides a detailed, in depth account of this varied experience. Sixteen studies were selected for inclusion and analysis was completed using thematic synthesis as the chosen approach. The results show that approaches to mental health service delivery and diagnosis at an individual, staff and system level can have huge ramifications for service users. Central to the findings was the importance of the therapeutic relationship. Recommendations include the provision of training around the difficulties associated with the BPD diagnosis and attachment for staff, and using elements of relational models such as Sociotherapy across services. The research paper seeks to ask what the concept of recovery means for the sense of self of individuals with a BPD diagnosis. Six service users were interviewed and the data was analysed using Interpretive Phenomenological Analysis. The resulting analysis produced four themes which showed that recovery is a complex, challenging and seemingly elusive process, understood in the context of ongoing difficulties, ambivalent views on diagnosis, and undeveloped sense of self. Recommendations include identifying difficulties around sense of self as goals for therapy where appropriate, and recognising the effect of attachment relationships. The critical appraisal details reflections on the thesis including the relational nature of the entire process

    The Papers of Thomas A. Edison

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    The second volume of The Papers of Thomas A. Edison, which covers the inventor's life from the end of June 1873 to the end of March 1876, reveals a remarkable diversity of activities and interests. During his late twenties Thomas Edison pursued his pathbreaking work in telegraph technology, formed a business alliance with the notorious financier Jay Gould, and became embroiled in a bitter legal battle over commercial rights to his quadruplex telegraph. Praise for previous volumes of The Papers of Thomas A. Edison:"The essence of the volume is Edison's technical notebooks, a window onto the inventor's workshop. His lucidity comes through everywhere . . . His writing and drawing come together as a single, vigorous thought process."—Russell McCormmach, New York Times."A mine of material . . . Scrupulously edited . . . No one could ask for more . . . A choplicking feast for Edison biographers—well into the next century, and perhaps beyond."—Fred Howard, Washington Post."A triumph of the bookmaker's art, with splendidly arranged illustrations, essential background information, and cautionary reminders of the common sources on which Edison's imagination drew."—David Joravsky, New York Review of Books."In the pages of this volume Edison the man, his work, and his times come alive . . . A delight to browse through or to read carefully."—Thomas J. Misa, Science

    Integrating BIM and GIS for design collaboration in railway projects

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    Collaboration is essential to achieve project targets and minimising rework in any project including railway projects. The railway project is considered as a megaproject that requires effective collaboration in order to achieve efficiency and effectiveness. To ensure that the railway continues to provide safe, reliable, cost-effective services, and remains environmentally friendly while driving economic growth, engaging new technologies and new types of work models are required. Among these technologies, Building Information Modelling (BIM) and Geographic Information Systems (GIS) are recent technologies that support collaboration. However, using these technologies to achieve effective collaboration is challenging, especially in railway projects as they are amongst the most complicated projects and often numerous parties are involved in making important decisions. Currently, there is a lack of evidence-based guidelines or processes for effective collaboration in railway projects throughout their design stage. Therefore, this thesis has focused on developing a process model to improve collaboration in the design stage of railway projects using BIM and GIS. This research adopted a mixed-methods approach to examine and identify the issues that hinder collaboration in railway projects to assist in developing theBIM and GIS-enabled collaboration process model. An online questionnaire was designed and distributed to professionals to assess the state-of-the-art in BIM and GIS followed by two rounds of in-depth interviews with experts. The first round aimed to identify collaboration issues and consisted of 15 in-depth, face to face and videoconference/telephone interviews; while the second round consisted of 10 in-depth interviews to identify the process model components of the collaborative process using IDEF technique.The questionnaire data were analysed using descriptive statistics and statistical tests (for example, Regression analysis, Wilcoxon Signed Ranks and Kruskal-Wallis Test). The results showed a lack of training in BIM and GIS and identified collaboration as a significant factor for railway projects, but there were many challenges to achieve effective collaboration. These challenges have been further investigated during the first round of interviews using content and thematic analysis. The results revealed that the most common challenges were getting the right information at the right time for the right purposes followed by resistance to change. Furthermore, the findings indicated that developing a process model, based on a clear plan of work demonstrating the collaboration process, is a potential solution to tackle these challenges. Thus, a Collaborative Plan of Work (CPW) has been developed through combining the RIBA (Royal Institute of British Architects) Plan of Work and the GRIP (Governance for Railway Investment Projects) stages. This CPW will be the basis to develop a process model for BIM and GIS-enabled collaboration. The results from the second round of the interviews identified the process model components which are: key players’ roles and responsibilities, tasks (BIM and GIS Uses), BIM and GIS-based deliverables, and critical decision points for collaborative process design. Moreover, this process model was formulated utilising Integrated DEFinition (IDEF) structured diagramming techniques (IDEF0 and IDEF3).In conclusion, the process model of the collaboration process and the integrated implementation of BIM and GIS sets out role and responsibilities, deliverables, and key decision points. Finally, the research outcomes have been validated through a focus group and interviews with professionals in the biggest Railway company where the proposed process model was operationalised using a commercial Common Data Environment platform (viewpoint 4project). From their discussion, feedback and recommendations the IDEF processes model have been refined. It is concluded that such a process is crucial for effective collaboration in railway projects as it enables the management of the design process in terms of technologies used, activities, deliverables, and decision points. Therefore, the research findings support the notion that BIM and GIS can help to achieve effective collaboration by delivering the right information at the right time for the right purposes. As a result, they help to achieve the projects’ objectives efficiently in terms of time, cost and effort.</div

    Re-use of tests and arguments for assesing dependable mixed-critically systems

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    The safety assessment of mixed-criticality systems (MCS) is a challenging activity due to system heterogeneity, design constraints and increasing complexity. The foundation for MCSs is the integrated architecture paradigm, where a compact hardware comprises multiple execution platforms and communication interfaces to implement concurrent functions with different safety requirements. Besides a computing platform providing adequate isolation and fault tolerance mechanism, the development of an MCS application shall also comply with the guidelines defined by the safety standards. A way to lower the overall MCS certification cost is to adopt a platform-based design (PBD) development approach. PBD is a model-based development (MBD) approach, where separate models of logic, hardware and deployment support the analysis of the resulting system properties and behaviour. The PBD development of MCSs benefits from a composition of modular safety properties (e.g. modular safety cases), which support the derivation of mixed-criticality product lines. The validation and verification (V&V) activities claim a substantial effort during the development of programmable electronics for safety-critical applications. As for the MCS dependability assessment, the purpose of the V&V is to provide evidences supporting the safety claims. The model-based development of MCSs adds more V&V tasks, because additional analysis (e.g., simulations) need to be carried out during the design phase. During the MCS integration phase, typically hardware-in-the-loop (HiL) plant simulators support the V&V campaigns, where test automation and fault-injection are the key to test repeatability and thorough exercise of the safety mechanisms. This dissertation proposes several V&V artefacts re-use strategies to perform an early verification at system level for a distributed MCS, artefacts that later would be reused up to the final stages in the development process: a test code re-use to verify the fault-tolerance mechanisms on a functional model of the system combined with a non-intrusive software fault-injection, a model to X-in-the-loop (XiL) and code-to-XiL re-use to provide models of the plant and distributed embedded nodes suited to the HiL simulator, and finally, an argumentation framework to support the automated composition and staged completion of modular safety-cases for dependability assessment, in the context of the platform-based development of mixed-criticality systems relying on the DREAMS harmonized platform.La dificultad para evaluar la seguridad de los sistemas de criticidad mixta (SCM) aumenta con la heterogeneidad del sistema, las restricciones de diseño y una complejidad creciente. Los SCM adoptan el paradigma de arquitectura integrada, donde un hardware embebido compacto comprende múltiples plataformas de ejecución e interfaces de comunicación para implementar funciones concurrentes y con diferentes requisitos de seguridad. Además de una plataforma de computación que provea un aislamiento y mecanismos de tolerancia a fallos adecuados, el desarrollo de una aplicación SCM además debe cumplir con las directrices definidas por las normas de seguridad. Una forma de reducir el coste global de la certificación de un SCM es adoptar un enfoque de desarrollo basado en plataforma (DBP). DBP es un enfoque de desarrollo basado en modelos (DBM), en el que modelos separados de lógica, hardware y despliegue soportan el análisis de las propiedades y el comportamiento emergente del sistema diseñado. El desarrollo DBP de SCMs se beneficia de una composición modular de propiedades de seguridad (por ejemplo, casos de seguridad modulares), que facilitan la definición de líneas de productos de criticidad mixta. Las actividades de verificación y validación (V&V) representan un esfuerzo sustancial durante el desarrollo de aplicaciones basadas en electrónica confiable. En la evaluación de la seguridad de un SCM el propósito de las actividades de V&V es obtener las evidencias que apoyen las aseveraciones de seguridad. El desarrollo basado en modelos de un SCM incrementa las tareas de V&V, porque permite realizar análisis adicionales (por ejemplo, simulaciones) durante la fase de diseño. En las campañas de pruebas de integración de un SCM habitualmente se emplean simuladores de planta hardware-in-the-loop (HiL), en donde la automatización de pruebas y la inyección de faltas son la clave para la repetitividad de las pruebas y para ejercitar completamente los mecanismos de tolerancia a fallos. Esta tesis propone diversas estrategias de reutilización de artefactos de V&V para la verificación temprana de un MCS distribuido, artefactos que se emplearán en ulteriores fases del desarrollo: la reutilización de código de prueba para verificar los mecanismos de tolerancia a fallos sobre un modelo funcional del sistema combinado con una inyección de fallos de software no intrusiva, la reutilización de modelo a X-in-the-loop (XiL) y código a XiL para obtener modelos de planta y nodos distribuidos aptos para el simulador HiL y, finalmente, un marco de argumentación para la composición automatizada y la compleción escalonada de casos de seguridad modulares, en el contexto del desarrollo basado en plataformas de sistemas de criticidad mixta empleando la plataforma armonizada DREAMS.Kritikotasun nahastuko sistemen segurtasun ebaluazioa jarduera neketsua da beraien heterogeneotasuna dela eta. Sistema hauen oinarria arkitektura integratuen paradigman datza, non hardware konpaktu batek exekuzio plataforma eta komunikazio interfaze ugari integratu ahal dituen segurtasun baldintza desberdineko funtzio konkurrenteak inplementatzeko. Konputazio plataformek isolamendu eta akatsen aurkako mekanismo egokiak emateaz gain, segurtasun arauek definituriko jarraibideak jarraitu behar dituzte kritikotasun mistodun aplikazioen garapenean. Sistema hauen zertifikazio prozesuaren kostua murrizteko aukera bat plataformetan oinarritutako garapenean (PBD) datza. Garapen planteamendu hau modeloetan oinarrituriko garapena da (MBD) non modeloaren logika, hardware eta garapen desberdinak sistemaren propietateen eta portaeraren aurka aztertzen diren. Kritikotasun mistodun sistemen PBD garapenak etekina ateratzen dio moduluetan oinarrituriko segurtasun propietateei, adibidez: segurtasun kasu modularrak (MSC). Modulu hauek kritikotasun mistodun produktu-lerroak ere hartzen dituzte kontutan. Berifikazio eta balioztatze (V&V) jarduerek esfortzu kontsideragarria eskatzen dute segurtasun-kiritikoetarako elektronika programagarrien garapenean. Kritikotasun mistodun sistemen konfiantzaren ebaluazioaren eta V&V jardueren helburua segurtasun eskariak jasotzen dituzten frogak proportzionatzea da. Kritikotasun mistodun sistemen modelo bidezko garapenek zeregin gehigarriak atxikitzen dizkio V&V jarduerari, fase honetan analisi gehigarriak (hots, simulazioak) zehazten direlako. Bestalde, kritikotasun mistodun sistemen integrazio fasean, hardware-in-the-loop (Hil) simulazio plantek V&V iniziatibak sostengatzen dituzte non testen automatizazioan eta akatsen txertaketan funtsezko jarduerak diren. Jarduera hauek frogen errepikapena eta segurtasun mekanismoak egiaztzea ahalbidetzen dute. Tesi honek V&V artefaktuen berrerabilpenerako estrategiak proposatzen ditu, kritikotasun mistodun sistemen egiaztatze azkarrerako sistema mailan eta garapen prozesuko azken faseetaraino erabili daitezkeenak. Esate baterako, test kodearen berrabilpena akats aurkako mekanismoak egiaztatzeko, modelotik X-in-the-loop (XiL)-ra eta kodetik XiL-rako konbertsioa HiL simulaziorako eta argumentazio egitura bat DREAMS Europear proiektuan definituriko arkitektura estiloan oinarrituriko segurtasun kasu modularrak automatikoki eta gradualki sortzeko

    Linguistic meta-theory the formal and empirical conditions of acceptability of linguistic theories and descriptions

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    Most linguists acknowledge, explicitly or implicitly, the relevance of epistemological questions in linguistics but relatively few have given more than a cursory, ad hoc or incomplete consideration to them. The work of one of those few, Jan Mulder, forms the starting point for much of the present discussion. Epistemological considerations arise in many contexts in linguistics and in many guises. It is an epistemological matter whenever we test the adequacy of a description or the acceptability of a theory. Epistemological considerations are latent whenever we discuss the form or the content of linguistic theories and descriptions or their interrelations. The comparison of different approaches to linguistics inevitably raises epistemological questions concerning our approach to linguistics or our presuppositions about it. These questions are of a general nature and transcend questions about particular linguistic theories and descriptions. These epistemological questions force us to consider what we take linguistics to be. In considering questions of the type mentioned we are forced, for example, to analyse what we mean by a "linguistic theory", a "linguistic description" and what phenomena we are aiming to understand. We are, furthermore, forced to analyse the constraints which a scientific attitude places upon linguistic theorising and description-building. It is these questions concerning the acceptability of linguistic theories and descriptions which we call linguistic meta-theory. This thesis falls into five main parts. Firstly, in Chapter One, we consider the nature and scope of linguistic meta-theory. Secondly, in Chapter Two, we look at a number of previous approaches to the subject. Other important contributions are discussed as they arise in the text. Thirdly, in Chapters Three and Four, we consider in detail the major meta-theoretical distinctions in linguistics and their consequences. In particular, we distinguish linguistic theories from linguistic descriptions and discuss the nature of linguistic phenomena. The view is put forward that linguistics is a scientific subject. The meaning of this assertion is analysed and the interrelations of linguistic theories, descriptions and phenomena are considered in the light of this analysis. The main epistemological requirement that is put forward and defended is that of the empiricism of linguistics. Certain changes in our view of the philosophy of science and in our view of the form of linguistic theories and descriptions follow from the conjunction of these major meta-theoretical positions. Fourthly, we consider the main meta-theoretical considerations concerning theories (Chapter Five) and reject a widespread view of linguistic theory as a non-empirical study (Chapter Six) and we consider the main meta-theoretical conditions relating to linguistic descriptions and some practical examples of description -building consonant with the general positions adopted in Chapter Seven. In Chapter Eight, we look at a concrete example of theory-building in the light of the meta-theoretical conditions of acceptability previously set up. We are especially concerned to show how a theory can meet the condition of being "applicable" or "indirectly scientific" through the establishment of acceptable empirical descriptions consonant with the meta-theoretical conditions on descriptions considered earlier. The view that linguistics is a science implies that we must be concerned with the empirical testing of descriptions and, so, the fifth part of the work is devoted to methodology. In Chapter Nine, we defend the role and necessity of methodology in linguistics and set up the logical framework of relations between the methodology and theory descriptions and phenomena. In Chapter Ten, we examine two of the known types of empirical testing and their shortcomings. Finally, in Chapter Eleven, we give an example of the successful and correct application of a methodology in order to bring out the nature of empirical testing and to demonstrate its feasibility within a scientific linguistics of the sort we imagine

    B.R. Wells Rice Research Studies 2011

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