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Goal Oriented Modeling Of Situation Awareness In A Command And Control SystemSoganci, Hasan Ali 01 December 2010 (has links) (PDF)
This thesis presents a preliminary goal oriented modeling of situation awareness in a command and control system. Tropos, an agent oriented software development methodology, has been used for modeling. Use of Tropos allows us to represent, at the knowledge level, the Command and Control actors along with their goals and interdependencies. Through refinement we aim to derive an architectural design for the Situation Awareness component of an Air Defense Command and Control system. This work suggests that goal oriented methodologies can be successfully used in the modeling of the complex systems at the requirement analysis phase. By analyzing dependencies between Command and Control entities, it should be possible to improve the modularity of the Command and Control system architecture.
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Effects Of Working Memory, Attention, And Expertise On Pilots' / Situation AwarenessCak, Serkan 01 July 2011 (has links) (PDF)
Situation Awareness (SA), is defined as perception of environmental entities, comprehension of their meaning, and estimation of their status in the near future (Endsley, 1995a). The general aim of the study is to investigate the relationship between SA and individual cognitive dierences. Specifically, the predictive value of working memory and attentional capacity measures on SA measures, taken from pilots of different expertise levels, is of interest. In the literature, SA has mostly been studied from an applied perspective. The present study therefore aims at providing the necessary
cognitive underpinnings of these more applied studies.
Two experiments were conducted. In Experiment 1, individual dierences and SA measures have been taken from thirty-six pilots. Automated Operation Span, Stroop Task, and Choice Reaction Time Task with Dichotic Listening were used for measuring working memory capacity (WMC), inhibition, and divided attention, respectively.
Online and offline SA measurements were employed together for tapping on different aspects of SA in a cognitively demanding flight scenario. Results showed that WMC and expertise explain 58% of variability in offline scores while inhibition, divided attention, and expertise explain 52% of variability in online scores. In Experiment 2, the aim was to find correlates of eye movements in terms of individual differences. Scan patterns were studied across four SA-related visual tasks with ten expert pilots. Results showed that more expert pilots produced less fixation durations but no other eects of individual dierences on the eye movements were observed. It was also observed that expert pilots deploy some scan strategies while performing these tasks.
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Data driven process monitoring based on neural networks and classification treesZhou, Yifeng 01 November 2005 (has links)
Process monitoring in the chemical and other process industries has been of great practical importance. Early detection of faults is critical in avoiding product quality deterioration, equipment damage, and personal injury. The goal of this dissertation is to develop process monitoring schemes that can be applied to complex process systems.
Neural networks have been a popular tool for modeling and pattern classification for monitoring of process systems. However, due to the prohibitive computational cost caused by high dimensionality and frequently changing operating conditions in batch processes, their applications have been difficult. The first part of this work tackles this problem by employing a polynomial-based data preprocessing step that greatly reduces the dimensionality of the neural network process model. The process measurements and manipulated variables go through a polynomial regression step and the polynomial coefficients, which are usually of far lower dimensionality than the original data, are used to build a neural network model to produce residuals for fault classification. Case studies show a significant reduction in neural model construction time and sometimes better classification results as well.
The second part of this research investigates classification trees as a promising approach to fault detection and classification. It is found that the underlying principles of classification trees often result in complicated trees even for rather simple problems, and construction time can excessive for high dimensional problems. Fisher Discriminant Analysis (FDA), which features an optimal linear discrimination between different faults and projects original data on to perpendicular scores, is used as a dimensionality reduction tool. Classification trees use the scores to separate observations into different fault classes. A procedure identifies the order of FDA scores that results in a minimum tree cost as the optimal order. Comparisons to other popular multivariate statistical analysis based methods indicate that the new scheme exhibits better performance on a benchmarking problem.
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Problem med militära och civila krishanteringssystemMöllenborg, Marcus January 2007 (has links)
<p>Att uppnå situationsmedvetenhet kan helt avgöra ifall en person klarar av att lösa en specifik uppgift eller inte. Dagens ledningssystem har ofta som uppgift att stödja användaren att upp nå situationsmedvetenhet och därmed klara av att lösa sina uppgifter. Detta examensarbete syftar till att undersöka vilka potentiella brister det kan tänkas finnas inom de militära och civila ledningssystemen. Att lista dessa problem är av intresse då det är av stor vikt att kunna se hur dessa system skulle kunna tänkas förbättras. Både utvecklare och användare har intervjuats i syfte att samla in viktiga åsikter. Resultatet blev en lista där de största problemen redovisades samt vilken inverkan de kan tänkas ha på användaren och dennes arbetsuppgifter.</p>
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Knowledge representation and stocastic multi-agent plan recognitionSuzic, Robert January 2005 (has links)
<p>To incorporate new technical advances into military domain and make those processes more <i>efficient</i> in accuracy, time and cost, a new concept of Network Centric Warfare has been introduced in the US military forces. In Sweden a similar concept has been studied under the name Network Based Defence (NBD). Here we present one of the methodologies, called tactical plan recognition that is aimed to support NBD in future.</p><p>Advances in sensor technology and modelling produce large sets of data for decision makers. To achieve <i>decision superiority</i>, decision makers have to act agile with proper, adequate and relevant information (data aggregates) available. Information fusion is a process aimed to support decision makers’ situation awareness. This involves a process of combining data and information from disparate sources with <i>prior</i> information or knowledge to obtain an improved state estimate about an agent or phenomena. <i>Plan recognition</i> is the term given to the process of inferring an agent’s intentions from a set of actions and is intended to support decision making.</p><p>The aim of this work has been to introduce a methodology where prior (empirical) knowledge (e.g. behaviour, environment and organization) is represented and combined with sensor data to recognize plans/behaviours of an agent or group of agents. We call this methodology <i>multi-agent plan recognition</i>. It includes knowledge representation as well as imprecise and statistical inference issues.</p><p>Successful plan recognition in large scale systems is heavily dependent on the data that is supplied. Therefore we introduce a <i>bridge</i> between the plan recognition and sensor management where results of our plan recognition are reused to the control of, give <i>focus of attention</i> to, the sensors that are supposed to acquire most important/<i>relevant</i> information.</p><p>Here we combine different theoretical methods (Bayesian Networks, Unified Modeling Language and Plan Recognition) and apply them for tactical military situations for ground forces. The results achieved from several proof-ofconcept models show that it is possible to model and recognize behaviour of tank units.</p>
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Environmental Research as a Tool for Change : Theoretical and methodological implications from two case studies producing knowledge for environmentally sustainable housingElfors, Susanna January 2006 (has links)
<p>The theme of this thesis is environmental research as a tool for change. In the first part of the thesis a “Situation of Opportunity” is studied, i.e. a situation when the opportunities to reduce negative environmental impacts are larger than usual. The maintenance of a multi- family residential area, here called a Small Neighbourhood, is studied as a series of Situations of Opportunity.</p><p>To explore the prerequisites for using maintenance as a Situation of Opportunity, two case studies were carried out and reported as a licentiate thesis. The first one on the rental area Idö-Våldö in Stockholm managed by the association Stockholms Kooperativa Bostadsförening (SKB), and the second one on Järven, a housing cooperative in Malmö that cooperates with the management organisation HSB Malmö. In the study the researcher developed long-term environmental strategies based on the planned maintenance of the areas. Besides exploring the prerequisites for using planned maintenance as a Situation of Opportunity, the intention was that the studies would initiate an environmental practice within the areas studied.</p><p>Results indicated that maintenance, at least in principle, creates many possibilities for reducing negative environmental impacts and that it to some extent also can be used for creating a dialogue between residents and managers. However, the conditions for using maintenance in the cases studied were limited by low interest among the residents as well as the economical and organisational prerequisites of the cases. The studies did not initiate an environmental practice as intended. The reason for that might be the mentioned conditions, but it could also depend on the researcher’s limited knowledge on action-oriented and collaborative research.</p><p>Thus, the second part of the thesis aims at developing a research methodology for such research. Based on empirical experiences from the Idö-Våldö and Järven-studies and a literature study, a methodology for action-oriented research for environmentally sustainable housing (ARESH) is outlined. It is proposed that methods of action research and of case study methodology could be applied in ARESH. However, there are several potential conflicts in ARESH. The researcher has for instance to judge if the study should be led in the first hand by participants or by researchers, or if it should be more oriented towards theory than practice. One conclusion is that a research methodology for such research needs to be further discussed and also further explored in practice. Since there are indications that a collaborative and action-oriented research is evolving in the field of environmental research, it is hoped that the findings of the thesis can contribute to a discussion on how to carry out research as a tool for change</p>
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Situation Assessment in a Stochastic Environment using Bayesian Networks / Situationsuppfattning med Bayesianska nätverk i en stokastisk omgivning.Ivansson, Johan January 2002 (has links)
<p>The mental workload for fighter pilots in modern air combat is extremely high. The pilot has to make fast dynamic decisions under high uncertainty and high time pressure. This is hard to perform in close encounters, but gets even harder when operating beyond visual range when the sensors of an aircraft become the pilot's eyes and ears. Although sensors provide good estimates for position and speed of an opponent, there is a big loss in the assessment of a situation. Important tactical events or situations can occur without the pilot noticing, which can change the outcome of a mission completely. This makes the development of an automated situation assessment system very important for future fighter aircraft. </p><p>This Master Thesis investigates the possibilities to design and implement an automated situation assessment system in a fighter aircraft. A Fuzzy-Bayesian hybrid technique is used in order to cope with the stochastic environment and making the development of the tactical situations library as clear and simple as possible.</p>
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Kvinnors livssituation i de indiska delstaterna Kerala och Punjab : - en jämförande deskriptiv studie / Women's life situations in the Indian states Kerala and Punjab : - a comparative descriptive studyOhlsson, Therese January 2008 (has links)
<p>Uppsatsen är en jämförande studie av kvinnors livsvillkor och förmåga att undkomma fattigdom i de två indiska delstaterna Kerala och Punjab. Båda delstaterna har höjt den allmänna levnadsstandarden i befolkningen men haft olika framgång i att få dessa att tillkomma kvinnor. Syftet med uppsatsen är att undersöka dels kvinnors livsvillkor och dels vilka faktorer som påverkar dessa i delstaterna. Metoden har bestått av kvalitativ textanalys. Vidare har statistik från UNDP använts. Studiens teoretiska referensram består av teorier om fattigdom och mänsklig utveckling av Amartya Sen och Martha Nussbaum, samt postkolonial feministisk teori av Chandra Mohanty. Uppsatsens slutsatser är att kvinnors livssituation i de två delstaterna beror till stor del på faktorer som distrikt, ort, klass, kast, stam, religiös tillhörighet, ordning i syskonskaran, samt position i familjen. Men det finns även regionala skillnader som påverkar kvinnors livsvillkor. I Punjab finns bl.a. en stark sonpreferens och flera patriarkala traditioner medan Kerala har tidigare matrilinjära traditioner samt ett starkt socialt skyddsnät. Vidare har delstaterna något olika politiskt fokus, olika traditioner och inställning till utbildning, olika traditioner kring kvinnors politiska organisering samt olika traditioner och sedvänjor gällande kvinnors position och frihet inom familjen som kan sägas gynna kvinnor i Kerala. Sammantaget kan sägas att kvinnors förmåga att undkomma fattigdom är något större i Kerala än i Punjab.</p>
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Contribution au pilotage des compétences dans les activités de conception : de la modélisation des situations à la caractérisation des compétences.Belkadi, Farouk 21 November 2006 (has links) (PDF)
Les évolutions rapides des exigences des clients, des technologies, des organisations, des méthodes et des outils de conception demandent aux concepteurs de développer constamment leurs compétences pour maintenir ou accroître les performances des projets de développement de nouveaux produits. Dans ce contexte, les managers et les concepteurs ont besoin d'outils pour les aider à améliorer le pilotage des compétencesmobilisées dans leurs activités. Notre contribution à cette problématique est double : d'une part, une modélisation des situations de travail pour réaliser la traçabilité des activités de conception et d'autre part, une approche floue pour caractériser les compétences. Pour la formalisation du concept de situation, nous avons proposé un cadre conceptuel définissant la situation par un ensemble d'entités qui participent, par des rôles spécifiques, à différentes interactions. Sur la base de ces concepts, nous avons proposé une modélisation UML de la situation pour structurer l'historique des activités de conception. Pour la caractérisation des compétences, nous avons proposé un modèle de la compétence regroupant un ensemble de connaissances techniques et quatre types de capacités estimées par une note relative. Le processus de caractérisation s'effectue sur deux étapes. La première est une qualification des différentes caractéristiques de la situation par des variables linguistiques. La deuxième est réalisée par un système de logique floue qui convertit le résultat de l'étape de "qualification de la situation" en valeur estimée des composants de la compétence associée. Notre première application en milieu industriel ouvre de nouvelles pistes de recherche. Elle nous a permis de confirmer la possibilité d'utiliser ce "principe de solution" pour répondre à d'autres problématiques de pilotage des compétences.
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Introduction de la notion de variation situatiolectale dans la grammaire scolaire par la caractérisation de deux opérateurs pragmatiques : on et çaGuerin, Emmanuelle 25 November 2006 (has links) (PDF)
Ce travail propose d'envisager l'introduction de la notion de variation en fonction des situations de communication dans la description grammaticale scolaire.Après avoir tenté de démontrer dans quelle mesure la dichotomie oral/écrit ne pouvait constituer un élément essentiel dans l'appareillage théorique nécessaire à la caractérisation des unités de la langue, nous avançons l'hypothèse que pourrait être considérée la variation situatiolectale, soit la variation en fonction des différents éléments relatifs à une situation de communication donnée.Ainsi, la sélection des unités lors de l'élaboration d'un énoncé, serait dépendante de l'appréhension que l'on a de ces différents éléments. L'emploi de on ou ça serait donc pertinent dès lors que la situation de communication permet une interprétation efficace. Nous et cela ne serait donc pas des équivalents préférables à l'écrit, mais des unités requerrant la combinaison de certains éléments situationnels autres.Nous avons donc cherché à caractériser on et ça afin de mettre en évidence leurs conditions d'emploi. Au terme de notre travail d'analyse, reposant notamment sur un corpus hétérogène, nous avons mis en question l'appartenance de on et ça à la classe des pronoms, du moins telle que l'on peut l'envisager selon la définition communément admise. En effet, il nous est apparu que l'interprétation de ces deux unités ne dépend pas uniquement du repérage en co- ou contexte d'un référent évoqué : il est nécessaire que les deux acteurs de la communication partagent une mémoire discursive suffisante à l'actualisation du référent selon une procédure spécifique à l'un et à l'autre. Ainsi, le simple fait que la langue se réalise par oral ou par écrit ne peut suffire à contraindre l'emploi de on plutôt que nous ou de ça plutôt que cela.De fait, sans remettre en cause l'enseignement nécessaire d'un modèle standard, il nous semble que la mise en lumière des raisons objectives pour lesquelles ce modèle s'organise à partir d'une sélection d'unités, en l'occurrence des unités interprétables sans que l'on ait à s'appuyer sur des connaissances et appréhensions partagées, donne du sens à cet enseignement.Par ailleurs, considérer que l'efficacité de l'emploi d'une unité est relative aux éléments constitutifs de la situation de communication permet de ne pas invalider d'emblée toute forme d'actualisation de la langue qui ne correspondrait pas au modèle, mais de leur attribuer une légitimité relative aux situations dans lesquelles elles sont pertinentes. Il s'agirait donc d'envisager un enseignement du standard qui ne nierait pas les compétences linguistiques des élèves acquises en dehors de l'école.
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