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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.
921

事件會計資訊系統之研究

詹靜秋, ZHAN, JING-GIU Unknown Date (has links)
近年來,電腦技術突飛猛進,其功能及成本效益與往昔相比,真是不可同日而語。電 腦容量大、速度快、計算精確已成為會計資訊處理不可或缺的輔助工具。然傳統會計 觀念、程序限制了電腦功能的發揮。本研究是引用事件方法之會計觀念與觀連式資料 庫技術加以整合。由於會計觀念與電腦技術緊密結合,使得事件會計資訊系統充分運 用電腦的功能,並克服不少傳統會計資訊系統的缺失。文中將一一討論事件方法、資 料統一整合、關連式資料庫的觀念;並以簡易製造業為例,說明事件資訊系統的設計 及操作;最後,將專章討論事件會計資訊系統在內部管理決策中所發揮的功能。
922

Tillämpning av GIS-analyser i MKB / Application of GIS-analyses in EIA

Wall, Erik January 2006 (has links)
<p>The reason for performing an Environmental Impact Assessment (EIA) is to incorporate environmental concern in different kinds of plans and projects. The purpose of such an assessment is to identify and describe direct, indirect and cumulative environmental impacts.</p><p>Geographical Information System (GIS) is a tool that can be used to combine spatial extension of both sensitive areas and different environmental impacts in a quick and easy way. Because of that, descriptions of environmental impacts and motivation of different standpoints on a specific issue can be more correct and easier to make if GIS is used as a tool.</p><p>Hence, GIS can contribute to improve the quality of Environmental Impact Assessments. If the benefits of using GIS are to out weight the costs, geographical information of satisfactory detail, actuality and accuracy need to be available at reasonable prices.</p><p>In this paper, case studies are carried out for three different geographical analyses to investigate the use of GIS as a tool in EIA. From these case studies, more general conclusions about the benefits and limitations of using GIS for Environmental Impact Assessments are also drawn. The criteria, after which benefits and limitations of GIS have been estimated, are data availability, time consumption for performing the analyses and how the results from the performed analyses can make impact assessments easier, motivate different standpoints and increase the comprehensiveness of the EIA-report.</p><p>The three different GIS-analyses includes calculation of pollution load in a catchment area, estimation of the visual impact from planned buildings and generation of alternative locations for underwater pipes. These analyses have been applied on one ongoing EIA for a freight terminal and one ongoing EIA for an underwater wastewater transmission pipe. The analyses in these case studies have been undertaken with ArcGIS software using the extensions “Spatial Analyst” and “3D Analyst”.</p><p>It is shown in this study that due to uncertainty in available model values and the time consuming data manipulation, it is unlikely that calculations of pollution loads with GIS will be used to any larger extent in EIA. To carry out visual assessments with help of GIS to estimate visual impacts is on the other hand assumed to be useful in EIA-work. Both to assess impacts and to estimate how changes in building design can alter those impacts. To use GIS to produce alternative locations for underwater pipes is also considered valuable in EIA-work, even though there is a considerable lack of data to predict the environmental class of marine areas and the connections between available data and real environmental values are weak. However, the risk of damaging vulnerable and high valued marine areas should decrease when applying this type of analyse.</p> / <p>Miljökonsekvensbeskrivningar (MKB) genomförs för att möjliggöra att hänsyn om miljön tas vid olika typer av exploateringsprojekt och exploateringsplaner. Syftet med en miljökonsekvensbeskrivning är att identifiera och beskriva direkta, indirekta och kumulativa miljöeffekter.</p><p>Geografiska informationssystem (GIS) är ett verktyg som kan användas för att snabbt och enkelt kombinera rumslig utsträckning av både känsliga områden och olika miljökonsekvenser. GIS kan därför användas för att underlätta beskrivningar av miljökonsekvenser och motivera olika ställningstaganden. Därigenom kan GIS bidra till bättre grundade och mer rättvisande miljökonsekvensbeskrivningar. Men för att vinsterna av att genomföra GIS-analyser ska överstiga kostnaderna krävs att geografisk information av tillräcklig detaljeringsgrad, aktualitet och säkerhet finns att tillgå till rimliga kostnader.</p><p>Syftet med denna studie har varit att genom fallstudier undersöka om tre olika GIS-analyser kan användas som verktyg i miljöbedömningar med idag tillgänglig data, samt att utifrån fallstudierna dra mer allmänna slutsatser om vinster och begränsningar av att använda GIS i miljökonsekvensbeskrivningar. De kriterier som har använts för att bedöma vinster och begränsningar är tidsåtgång för analyserna, tillgång på data samt hur analyserna kan vara ett stöd i MKB-arbetet genom att underlätta beskrivningar av konsekvenser, motivera ställningstaganden som görs och öka rapportens begriplighet.</p><p>De tre genomförda GIS-analyserna innefattar beräkning av föroreningsbelastning inom ett avrinningsområde, bedömning av byggnaders landskapspåverkan genom synlighetsanalys samt generering av förslag till alternativ ledningsdragning för en undervattensledning. Dessa analyser har tillämpats på en pågående MKB för en detaljplan för en partihall och en pågående MKB för en avloppsvattenledning under vatten. Analyserna i fallstudierna har genomförts i programmet ArcGIS med tilläggen ”Spatial Analyst” och ”3D Analyst”.</p><p>Studien visar att det på grund av osäkerheter i tillgängliga schablonvärden och tidsåtgång för databehandling är osannolikt att beräkning av föroreningsmängd inom ett avrinningsområde med GIS kommer att användas till någon större utsträckning i MKB. Att med GIS genomföra synlighetsanalyser för att utvärdera landskapspåverkan bedöms däremot kunna användas i MKB, både för att bedöma påverkan och för att utvärdera hur en förändring i en byggnads utformning kan förändra den påverkan. Även att med GIS generera förslag till alternativa ledningsdragningar under vatten bedöms kunna fylla en funktion i MKB trots att tillgången på data för att kunna beskriva olika marina områdens naturvärden är klart bristfällig och kopplingen mellan tillgängliga data och verkliga naturvärden är osäker. Denna typ av analys bör ändå minska risken att värdefulla och skyddsvärda marina områden skadas vid lednignsdragning.</p>
923

Another bit bytes the dust: the technological and human challenges of digital preservation

Zaste, Chris 12 January 2017 (has links)
Digital communication produces millions of emails, text messages, movies, images, and much more every day. As with all historical records, digital records are important to preserve because they allow us to study the past. There are, however, several challenges regarding their preservation. Unlike many of their analogue counterparts, digital records rely on a combination of hardware and software to be accessible, but hardware and software eventually degrade and become obsolete. This makes digital records inaccessible because the means to render them are no longer available. In addition to these technological challenges, there are issues surrounding appraisal, copyright, significant properties, and metadata. This thesis studies the challenges of digital preservation and what is being done to address them. I begin by introducing the challenges surrounding this topic and the methods of preservation that are currently available to archivists. I then analyse leading digital preservation standards such as the Reference Model for an Open Archival Information System (OAIS) and Preservation Metadata: Implementation Strategies (PREMIS) as well as digital preservation systems including Archivematica and Preservica. I also conduct a case study of Archivematica to analyse how well it manages the challenges of digital preservation. I conclude by explaining that there are no perfect solutions to digital preservation problems. The best that can currently be done is to manage the issues rather than solve them. / February 2017
924

Localication et cartographie simultanées par vision monoculaire contraintes par un SIG : application à la géolocalisation d'un véhicule / Monocular SLAM contrained with GIS data and its Application to vision-based Vehicle Geo-localization

Lothe, Pierre 08 October 2010 (has links)
Les travaux réalisés au cours de cette thèse s’inscrivent dans les problématiques de localisation d’un véhicule par vision. Nous nous plaçons en particulier dans le cas de parcours sur de longues distances, c’est à dire plusieurs kilomètres. Les méthodes actuelles de localisation et cartographie simultanées souffrent de problèmes de dérives qui les rendent difficilement exploitables après plusieurs centaines de mètres. Nous proposons dans ce mémoire de pallier ces limites en exploitant une connaissance à priori sur la géométrie de l’environnement parcouru.Cette information est extraite d’un Système d’Information Géographique. En particulier, les travaux réalisés se basent sur les modèles 3D des bâtiments des villes et sur une carte de la route.Dans la première partie de ce mémoire, nous proposons une approche permettant de corriger hors ligne une reconstruction SLAM en exploitant la connaissance d’un modèle 3D simple de l’environnement. Cette correction s’applique en deux étapes. En premier lieu, un recalage non-rigide entre le nuage de points reconstruit et le modèle 3D est effectué de sorte à retrouver la cohérence globale de la reconstruction. Dans le but de raffiner le nuage de points obtenu, un ajustement de faisceaux contraint par le SIG est alors effectué sur l’ensemble de la reconstruction.La particularité de cet ajustement de faisceaux est qu’il prend implicitement en compte les contraintes géométriques apportées par le modèle 3D. La reconstruction ainsi corrigée est alors utilisée en tant que base de données pour la relocalisation en ligne d’une caméra mobile. La précision de relocalisation obtenue est en particulier suffisante pour les applications de réalité augmentée.Dans la deuxième partie de ce mémoire, nous détaillons une solution permettant de corriger en ligne la reconstruction SLAM. Pour cela, les contraintes géométriques apportées par le SIG sont exploitées au fur et à mesure de la trajectoire du véhicule. Nous montrons tout d’abord que la connaissance de la position relative de la caméra par rapport à la route permet de corriger de façon robuste la dérive de facteur d’échelle. De plus, lorsque les contraintes géométriques sont suffisantes, la reconstruction SLAM réalisée jusqu’à l’instant courant est recalée sur le SIG.Cela permet de corriger ponctuellement la dérive observée sur la position courante de la caméra.Le processus complet permet dès lors de localiser le véhicule avec une précision semblable à celle d’un système GPS sur des trajectoires de plusieurs kilomètres.Les deux méthodes proposées ont été testées à la fois sur des séquences de synthèse et réelles. Des résultats qualitatifs et quantitatifs sont présentés tout au long de ce mémoire. / This thesis deals with the vision based geolocalisation of a vehicle. In particular, the problem of localisation on large sequences, i.e. several kilometers, is studied. In this context, state of the art Simultaneous Localisation and Mapping systems suffer from drift. In consequence,existing SLAM methods can not provide accurate localisation of the camera after several hundred meters. Thus, we propose in this thesis to avoid the drift phenomenon by exploiting a simple knowledge about the geometry of the environment. This information is provided by a Geographical Information System. In particular, our work is based on coarse 3D city models and road maps.In the first part, we propose an offline two steps correction of SLAM reconstructions based on a 3D city model of the area. First, the reconstructed 3D point cloud and this 3D city model are aligned through a non-rigid transformation. This step allows the SLAM reconstruction to regain its global consistency. Then, a bundle adjustment constrained with the GIS is applied on the entire reconstruction to refine its geometry. The innovation of this bundle adjustment is that it takes into account the geometrical constraints provided by the 3D city model in a single term.The obtained 3D point cloud can then be considered as a feature landmark database. Finally, this database is used to localise a moving camera in real-time. In pratice, the precision of the obtained localisation is sufficient for augmented reality applications. In the second part of this manuscript, we present a solution which makes possible the online correction of a SLAM reconstruction. The GIS geometrical constraints are exploited over the vehicle trajectory. First, we show that the scale factor drift can be robustly corrected thanks to the knowledge of the ground plane equation. Furthermore, the current SLAM reconstruction is fitted onto the GIS when the geometrical constraints are sufficient. It punctually ensures the correction of the current camera position. The entire process allows the geolocalisation of a vehicle on several kilometers. The obtained precision is close to GPS.The two proposed solutions have been validated of both synthetic and real sequences. Quantitative and qualitative experiments are presented over this manuscript.
925

Achieving Solution Success: An Investigation of User Participation Approaches

Mattia, Angela 28 April 2009 (has links)
User participation and its relationship to system success have been discussed in the information systems (IS) literature from many theoretical and practical perspectives. In reality, most of this discussion is grounded in empirical research that has yielded mixed results on the importance of user participation and its relationship to system success. The goal of this dissertation is to extend the line of inquiry into user participation during information system development by providing information systems researchers and IS practitioners with both a valid theoretical and practical investigation of a successful IS solution. This investigation organizes the study within a descriptive model that emerges from the different traditions of prior research and uncovers the approach to user participation in a successful IS solution. This user participation approach (UPA) model becomes the structure for the systematic arrangement of user participation approaches into a four-fold typology according to criteria or extrinsic information attributed to them in the research literature. A case study analysis and social network analysis of a successful IS solution will be used to describe, map and measure the relationships, activities, processes, and flows between participants, thus providing a descriptive and visual analysis of the relational structure that emerges. Indeed, these methodological approaches conceptualize the attributes and the relations of user participation during information system development and give insightful perspectives on how a successful IS solution is developed and implemented. The resulting outcome is a description of a successful approach to user participation and some practical recommendations on how to increase the chance of success in a system solution.
926

DIVERGENCE IN STAKEHOLDER PERCEPTIONS OF SECURITY POLICIES: A REPGRID ANALYSIS FOR NORM-RULE COMPLIANCE

Almusharraf, Ahlam 01 January 2016 (has links)
Many organizations have a problem with synchronizing individual values regarding information security with expectations set by the relevant security policy. Such discordance leads to failure in compliance or simply subversion of existing or imposed controls. The problem of the mismatch in understanding the security policies amongst individuals in an organization has devastating effect on security of the organization. Different individuals hold different understanding and knowledge about IS security, which is reflected on IS security policies design and practice (Vaast, 2007). Albrecthsen and Hovdena (2009) argue that users and managers practice IS security differently because they have different rationalities. This difference in rationalities may reflect the mismatch between the security policies and individuals’ values. In this research, we argue that occurrence of security breach can change individuals’ values in light of security policy of organization. These changes in the values can be reflected on the compliance between individuals’ norms and security rules and standards. Indeed, organizations need to guarantee the compliance between security policy and values of their employees. Thus, they can alleviate or prevent violations of security of organization. However, it is difficult to find a common method that all organizations can adopt to guarantee the synch between security rules and individuals’ norms. The main aim of this research is to investigate how people perceive information security policy and how their perceptions change in response to security breaches. Besides, this research aims to investigate the relationship between individuals’ values and security policy. Thus, organizations can have the intended level of compliance between individual norms and security rules and standards. With the aid of the Repertory Grid technique, this research examines how a security breach shapes people’s values with respect to security policy of an organization. To conduct the argument, this research offers an assessment mechanism that aids the organization to evaluate employees’ values in regard to security policy. Based on that evaluation, the organization can develop a proper mechanism to guarantee compliance between individuals’ norms and security rules. The results of this research show that employees in an organization hold different perceptions regarding the security policy. These perceptions change in response to security incident. This change in perceptions dose not necessarily result in better compliance with the security policy. Factors like the type of breach and people’s experience can affect the amount of change in the perceptions. Contributions, implications, and directions for future research of this study will be discussed.
927

Valuing Natural Space and Landscape Fragmentation in Richmond, VA

Carpenter, Lee Wyatt 01 January 2016 (has links)
Hedonic pricing methods and GIS (Geographic Information Systems) were used to evaluate relationships between sale price of single family homes and landscape fragmentation and natural land cover. Spatial regression analyses found that sale prices increase as landscapes become less fragmented and the amount of natural land cover around a home increases. The projected growth in population and employment in the Richmond, Virginia region and subsequent increases in land development and landscape fragmentation presents a challenge to sustaining intact healthy ecosystems in the Richmond region. Spatial regression analyses helped illuminate how land cover patterns influence sale prices and landscape patterns that are economically and ecologically advantageous.
928

Investigating enterprise application integration (EAI) adoption factors in higher education : an empirical study

Aserey, Naseir January 2015 (has links)
The Higher Education (HE) sector of a country is a key area indicating the progress of cultural, political and social growth and development. Public and social demands as well as technological developments add new challenges for this sector. Consequently, higher education institutions have changed and a more flexible IT infrastructure is required to enable them to adapt efficiently to competitive business challenges. Enterprise application integration (EAI) is a technology that effectively integrates intra- and inter-organizational systems. Firstly a systematic review of the EAI literature was conducted. From this review, it was apparent that there are no theoretical models for EAI adoption and evaluation for higher education. Hence, this research contributes a conceptual model that includes influential factors derived from the literature and combines them with the proposed classification of influential factors for HE to produce an EAI conceptual model for the HE domain. To validate this proposed model empirical research was conducted. Then, the model was tested using a qualitative case study approach by means of three case studies that were conducted at different universities. Exploratory, explanatory and interpretive data analysis phases were implemented to find what is the current EAI process of HE and how these institutions currently work. In addition, these phases were employed to identify the EAI adoption factors in HE. As a result of this analysis the conceptual model was modified because of complementary factors that emerged. Therefore, the main contribution of this research is a comprehensive and novel model for EAI adoption in higher education area. The adoption EAI factors were identified by extracting a number of parameters from the empirical data. Several important factors that influence and assist the adoption of EAI in HE were identified. Hence, an additional contribution is the classification of factors in EAI adoption into technical and social factors which provides a better understanding of these factors. A further contribution is the derivation of a new classification of the EAI external and internal pressure factors. The development of a consistent model for the adoption and evaluation of EAI in HE is based on these factors.
929

Modélisation de l'activité en chirurgie vasculaire

Berger, Ludovic 19 December 2011 (has links)
La question du remplacement des chirurgiens vasculaires pour les années à venir est préoccupante du fait d’un grand nombre de départs en retraite. Mais la question du seul remplacement des effectifs ne suffit pas pour une spécialité qui s’adresse principalement à des patients âgés dans le contexte actuel d’augmentation et de vieillissement de la population française.Dans le but de répondre aux besoins en chirurgie vasculaire dans les années futures, nous avons dans un premier temps réalisé un état des lieux de la démographie des praticiens de la spécialité et estimé la cinétique des départs en retraite des prochaines années.Pour pouvoir tenir compte de l’évolution de la future activité, nous avons établi un modèle prédictif de cette activité concernant les actes de chirurgie carotidienne, de chirurgie des anévrysmes de l’aorte abdominale sous-rénale et de chirurgie des artères sous-inguinales, d’après le seul vieillissement de la population. Ce modèle applique les méthodes de l’INSEE aux actes recueillis dans le Programme Médicalisé des Systèmes d’Information. Nous l’avons ensuite affiné par l’intégration d’autres paramètres influençant l’évolution de l’activité grâce au calcul et à l’application d’un coefficient de pondération obtenu sur la période d’activité de 2000 à 2008. D’après le modèle, l’activité entre 2008 et 2030 augmentera de 38% sur les segments étudiés.Les projections pondérées permettent de prédire une augmentation de l’activité de 30% entre 2011 et 2025. D’un point de vue purement mathématique, les besoins de formation seraient de 120 chirurgiens pour le remplacement des départs en retraite, et de 59 chirurgiens supplémentaires du fait de l’augmentation de l’activité. / The question of replacement of vascular surgeons for the future is of concern because of a large number of retirements. But the question of replacement only is not sufficient for a specialty that is primarily for older patients in the current context of increasing and aging of the French population.In order to meet the need for vascular surgery in the coming years, we initially performed an overview of the demographics of practitioners of the specialty and estimated the retirements. To take into account the evolution of the future activity, we have established a predictive model for the acts of carotid surgery, surgery of infrarenal abdominal aortic aneurysms and surgery of peripheral arterial disease, according to the aging population. This model applies the methods of the INSEE for acts collected in the Medicalised Information System Program database.We then refined it by including other parameters modifying workload evolution. We have calculated and applied a weighting factor obtained during the period of activity from 2000 to 2008. According to the model, the activity between 2008 and 2030 will increase by 38% in the studied procedures.The weighted projections predict an acts’ increase 30% between 2011 and 2025.From a purely mathematical point of view, the training needs of 120 surgeons would be to replace retirements, and 59 more surgeons because of the increased workload.
930

Un processus formel d'intégration de politiques de contrôle d'accès dans les systèmes d'information / A formal integration of access control policies into information systems

Milhau, Jérémy 12 December 2011 (has links)
La sécurité est un élément crucial dans le développement d'un système d'information. On ne peut pas concevoir un système bancaire sans préoccupation sécuritaire. La sensibilité des données d'un système hospitalier nécessite que la sécurité soit la composante majeure d'un tel logiciel. Le contrôle d'accès est un des nombreux aspects de la sécurité. Il permet de définir les conditions de l'exécution d'actions dans un système par un utilisateur. Entre les différentes phases de conception d'une politique de contrôle d'accès et son application effective sur un système déployé, de nombreuses étapes peuvent introduire des erreurs ou des failles non souhaitables. L'utilisation de méthodes formelles est une réponse à ces préoccupations dans le cadre de la modélisation de politiques de contrôle d'accès. L'algèbre de processus EB3 permet une modélisation formelle de systèmes d'information. Son extension EB3SEC a été conçue pour la spécification de politiques de contrôle d'accès. Le langage ASTD, combinaison des statecharts de Harel et des opérateurs de EB3, permet de modéliser graphiquement et formellement un système d'information. Cependant, ces deux méthodes manquent d'outils de vérification et de validation qui permettent de prouver ou de vérifier des propriétés de sécurité indispensables à la validation de politiques de contrôle d'accès. De plus, il est important de pouvoir prouver que l'implémentation d'une politique correspond bien à sa spécification abstraite. Cette thèse définit des règles de traduction de EB3 vers ASTD, d'ASTD vers event-B et vers B. Elle décrit également une architecture formelle exprimée en B d'un filtre de contrôle d'accès pour les systèmes d'information. Cette modélisation en B permet de prouver des propriétés à l'aide du prouveur B ou de vérifier des propriétés avec ProB, un vérificateur de modèles. Enfin, une stratégie de raffinement B pour obtenir une implémentation de ce filtre de contrôle d'accès est présentée. Les raffinements B étant prouvés, l'implémentation correspond donc au modèle initial de la politique de contrôle d'accès / Security is a key aspect in information systems (IS) development. One cannot build a bank IS without security in mind. In medical IS, security is one of the most important features of the software. Access control is one of many security aspects of an IS. It defines permitted or forbidden execution of system's actions by a user. Between the conception of an access control policy and its effective deployment on an IS, several steps can introduce unacceptable errors. Using formal methods may be an answer to reduce errors during the modeling of access control policies. Using the process algebra EB3, one can formally model IS. Its extension, EB3SEC, was created in order to model access control policies. The ASTD notation combines Harel's Statecharts and EB3 operators into a graphical and formal notation that can be used in order to model IS. However, both methods lack tools allowing a designer to prove or verify security properties in order to validate an access control policy. Furthermore, the implementation of an access control policy must correspond to its abstract specification. This thesis defines translation rules from EB3 to ASTD, from ASTD to event-B and from ASTD to B. It also introduces a formal architecture expressed using the B notation in order to enforce a policy over an IS. This modeling of access control policies in B can be used in order to prove properties, thanks to the B prover, but also to verify properties using ProB, a model checker for B. Finally, a refinement strategy for the access control policy into an implementation is proposed. B refinements are proved, this ensures that the implementation corresponds to the initial model of the access control policy

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