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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.
31

Desarrollo de un sistema de identificación reprogramable de paletas en una línea de producción orientado a la educación de costos del proceso de trazabilidad mediante un dispositivo IoT en una embotelladora de la ciudad de Lima / Development of a reprogrammable identification system for pallets in a production line aimed at reducing the costs of the traceability process using an IoT device in a bottling plant in the city of Lima

Garcilazo Zuloeta, Kevin Cesar, Lamarque Zela, Jorge Luis 13 September 2021 (has links)
El presente trabajo propone el desarrollo de un sistema de identificación de trazabilidad de paletas dentro de un almacén de una compañía embotelladora de bebidas en la ciudad de Lima. El uso de dispositivos IOT forma parte de la solución planteada para establecer parámetros de medición los cuales son el eje fundamental para determinar la distancia entre los equipos de etiquetado e identificación. Los parámetros serán usados en redes de área personal (WPAN) para establecer umbrales que pueden variar por la tecnología a emplear de Wifi en la banda de 2.4Ghz por el indicador de fuerza de la señal recibida (RSSI). El problema actual que presenta la compañía es un consumo de materiales no reutilizables dedicados a la identificación de paletas. El método de etiquetado actual produce un consumo anual de 1440 Kg de papel por cada línea de producción de las 11 que dispone la planta. El proceso de trazabilidad propuesto sigue los fundamentos del sistema de localización en tiempo real (RTLS) para sistemas de posicionamiento en interiores (IPS) el cual identificará los puntos clave para establecer la correcta comunicación entre los dispositivos de etiquetado e identificación. El dispositivo de etiquetado almacenara un código numérico que representa la etiqueta del proceso actual cuyos valores contienen información codificada del producto empaquetado sobre las paletas. Durante el proceso planteado los dispositivos de etiquetado harán uso de los dispositivos de identificación para determinar y enviar un conjunto de valores al sistema de monitoreo central para ser registrados, analizados y visualizados. En términos generales la solución propuesta tiene como objetivo reducir en más de un 80% el tiempo de identificación y más de un 60% el coste de mantenimiento del sistema de identificación de paletas. / The current job proposes the development of a pallet identification and traceability system within a warehouse of a beverage bottling company in the city of Lima. The use of IoT devices is part of the solution proposed to establish measurement parameters which are the fundamental axis to determine the distance between the labeling and identification equipment. The parameters will be used in personal area networks (WPAN) to establish thresholds that may vary by the technology to be used from Wi-Fi in the 2.4Ghz band by the received signal strength indicator (RSSI). The current problem of the company presents a consumption of non-reusable materials dedicated to the identification of pallets. The current labeling method produces an annual consumption of 1440 kg of paper for each production line of the 11 that the plant has. The proposed traceability process follows the fundamentals of the real-time location system (RTLS) for indoor positioning systems (IPS) which will identify the key points to establish the correct communication between the labeling and identification devices. The labeling device will store a numerical code that represents the current process label whose values contain encoded information of the packaged product on the pallets. During the proposed process, the labeling devices will make use of the identification devices to determine and send a set of values to the central monitoring system to be recorded, analyzed and visualized. In general terms, the proposed solution aims to reduce by 80% the palette identification time and by 60% the cost of maintenance of the identification system. / Tesis
32

De l'agrandissement des exploitations agricoles à la transformation des paysages de bocage : analyse comparative des recompositions foncières et paysagères en Normandie / From farms enlargment to the bocage landscape dynamics : comparative analysis of the contribution of the farm spatial extension to landscape dynamics in Normandy

Preux, Thibaut 05 December 2019 (has links)
Paysages emblématiques des campagnes de l’Ouest, les bocages ont connu une série de transformations rapides et importantes ces quarante dernières années : érosion du linéaire de haies, changements des usages du sol, rationalisation et agrandissement du parcellaire, banalisation et massification des bâtiments agricoles, enfrichement des secteurs les plus difficiles à exploiter. L’ampleur des ajustements observés souligne le décalage entre ces formes paysagères héritées d’une longue histoire agraire, et l’évolution des systèmes agricoles qui contribuent à les produire.Si la transformation des paysages de bocage est généralement attribuée au tournant « productiviste » du modèle agricole français, les processus socio-techniques à l’origine de ces évolutions sont plus rarement explicités. L’objet de ce travail est d’évaluer plus spécifiquement la contribution de l’agrandissement des exploitations agricoles à la dynamique d’évolution des paysages bocagers de l’Ouest de la France.Ce travail de géographie s’appuie dans un premier temps sur une analyse statistique à l’échelle du grand Ouest de la France, visant à étudier l’effet des transformations foncières sur les structures spatiales agricoles (assolements, parcellaire, linéaires boisés…). Dans un second temps, les dynamiques paysagères et foncières de quatre espaces d’étude (Bessin, Bocage Virois, Sud Manche, Pays d’Auge), situés en domaine laitier et bocager mais présentant des configurations agricoles variées, ont été étudiées entre 2003 et 2016. Ce travail s’appuie notamment sur un dispositif méthodologique original, articulant au sein d’un système d’information géographique à échelle parcellaire (1) la construction d’un suivi à échelle spatio-temporelle fine des dynamiques paysagères (évolution du maillage bocager, de la trame parcellaire et de l’occupation du sol) et (2) la reconstitution de l’évolution de la mosaïque des parcellaires d’exploitations par appariement de plusieurs millésimes du registre parcellaire graphique. L’exploitation de cette base de données spatio-temporelle a permis de mieux comprendre le rôle de la transformation foncière des exploitations agricoles dans la dynamique des paysages bocagers. Enfin, une enquête de terrain a été réalisée auprès de 150 agriculteurs équitablement répartis dans les quatre espaces d’étude, afin d’appréhender les conséquences sociales, techniques et productives de l’agrandissement à l’échelle des exploitations agricoles, qui diffèrent singulièrement selon le type de trajectoire foncière suivie. / Symbolic landscapes of the countryside of the West of France, the bocage landscapes have undergone a series of transformations these last forty years : decrease in hedgerow density, land uses changes, plots extension, normalization and enlargement of farm buildings, spatial extension of wilderness… The intensity of landscape transformations highlights the contradiction between these landscape forms produced by a long agrarian history and the contemporary evolutions of farming systems. The transformation of hedgerow landscapes is generally attributed to the "productivist" turn of the French agricultural model. However, the socio-technical processes behind these changes are more rarely explained.The first purpose of this geography work is to study the effects of changing agricultural systems on agricultural spatial structures, based on a statistical analysis at the scale of the West of France. In a second step, the landscape and land dynamics of four study areas (Bessin, Bocage Virois, Sud Manche, Pays d'Auge), located in the dairy and bocage domain, have been studied between 2003 and 2016. This work is based on an original methodological device, set up in a geographical information system. This structuration of geographic information makes possible to (1) monitor the landscape dynamics (evolution of the hedgerow density, land cover and plot morphology changes) at a fine spatial and temporal scale and (2) to reconstruct the evolution of the mosaic of farm plots, by matching land-parcell identification systems across the time (2007, 2011, 2013). From this spatio-temporal database, we characterized the coevolution of landscape structures and farm territories across the time, in order to better understand the landscape consequences of farm enlargment.Finally, a field survey was carried out among 150 farmers equitably distributed in the four study areas, in order to apprehend the social, technical and productive consequences of the farms enlargment, which differ singularly according to the type of land trajectory followed.
33

Implementace Digital Object Identifier na univerzitách v České republice: zkušenosti a doporučení / The implementation of Digital Object Identifier at the univerisities in Czech Republic: experience and recommendations

Rumpíková, Kristina January 2019 (has links)
(in English): The aim of this thesis is to present persistent identification system of digital object identifier and analyze of use of DOI on a sample of public universities in the Czech Republic. The first part introduce the DOI system, its structure, advantages and examples of use in recent time. The second part is focused on analysis of current use of DOI in public univeristies. To fullfil this purpose researched questions were stated. Data was collected were determined in questionaire survey and semi structured interview. The conclusion of thesis proposes a direction of further reflection towards improvement of current situation.
34

Persistentní identifikátory a jejich využití v digitálních knihovnách / Persistent identifiers and their use in digital libraries

Jílková, Marta January 2013 (has links)
The aim of this thesis is to present persistent identification systems and analysis of the use of persistent identifiers for digital objects on a sample of national digital libraries. The first part is a brief introduction to digital libraries. The second part describes selected permanent identification systems. The third part explains elements of selected national digital libraries. The last section is an analysis of the use of persistent identifiers in various national digital libraries. Keywords: persistent identifier, persistent identification system, URI, URN, PURL, Handle, DOI, ARK, digital library, national library, digital object
35

Big Maritime Data: The promises and perils of the Automatic Identification System : Shipowners and operators’ perceptions

Kouvaras, Andreas January 2022 (has links)
The term Big Data has been gaining importance both at the academic and at the business level. Information technology plays a critical role in shipping since there is a high demand for fast transfer and communication between the parts of a shipping contract. The development of Automatic Identification System (AIS) is intended to improve maritime safety by tracking the vessels and exchange inter-ship information.  This master’s thesis purpose was to a) investigate in which business decisions the Automatic Identification System helps the shipowners and operators (i.e., users), b) find the benefits and perils arisen from its use, and c) investigate the possible improvements based on the users’ perceptions. This master’s thesis is a qualitative study using the interpretivism paradigm. Data were collected through semi-structured interviews. A total of 6 people participated with the following criteria: a) position on technical department or DPA or shipowner, b) participating on business decisions, c) shipping company owns a fleet, and d) deals with AIS data. The Thematic Analysis led to twenty-six codes, twelve categories and five concepts. Empirical findings showed that AIS data mostly contributes to make strategic business decisions. Participants are interested in using AIS data to measure the efficiency of their fleet and ports, to estimate the fuel consumption, to reduce their costs, to protect the environment and people’s health, to analyze the trade market, to predict the time of arrival, the optimal route and speed, to maintain highest security levels and to reduce the inaccuracies due to manual input of some AIS attributes. Finally, participants mentioned some AIS challenges including technological improvement (e.g., transponders, antennas) as well as the operation of autonomous vessels.  Finally, this master’s thesis contributes using the prescriptive and descriptive theories and help stakeholders to find new decisions while researchers and developers to advance their products.
36

Addressing Challenges with Big Data for Maritime Navigation: AIS Data within the Great Lakes System

Dhar, Samir January 2016 (has links)
No description available.
37

Spårbarhetsanalys på serieproduktion : En studie om spårbarhetspåverkan inom serieproduktion / Traceability analysis in serial production : A study on the impact of traceability in serial production

Berg, Vilhelm, Sandgren, Jonas January 2022 (has links)
En produktion utan spårbarhet leder till sekundära problem och mer arbete vid reklamationer från flera olika kunder där samma komponent är felande eller inte uppnår uppsatta kravspecifikationerna, det finns en nytta med att veta i vilka fler slutprodukter fler komponenter från samma batch sitter. Då kan de bytas ut eller servicepaket kan skickas ut till kund innan det uppstår komplikationer för kunden. Kund- och lagkrav på att kunna spåra kritiska komponenter inom medicinteknik för att få leverera finns.    Spårbarhetsanalysen för att generera ett lösningsförslag för fallstudien grundar sig i en blandning av kvalitativ- och kvantitativ datainsamling. Intervjuer och litteraturstudie tillsammans med produktionsdata ligger fundament för framtagning av vilken nivå som lämpar sig och vilken lösning som bör implementeras i nuläget.    Resultatet är att skapa förutsättningar för att kunna spåra komponenter. Lösningen bygger på ett inhouse standardiserat 2-bin kanbansystem med FIFO (first in first out). Informationen registreras på samtliga lagerplatser och följer materialet genom produktionsflödet. Det information som ska följa med materialet är tid och datum vid ankomst, leverantör, kvantitet och artikelnummer. Detta behövs implementeras på samtliga lagerhållningsplatser för att informationen ska följa med till utleverans och slutproduktens individuella identifieringsnummer.    Genom analysmetoderna släktskapsträd, PICK-chart och 5 varför har resultatet framtagits. Eliminering av lösningar som inte är aktuella i nuläget har även belysts i analyserna. Jämförelse av flödesanalys genom simulering har gett ett mått på hur detta påverkar produktionen i helhet.    Studien kan användas som första steget i ett PDCA-projekt (Plan, Do, Check, Act) där denna rapport står för planeringsfasen. Genomförande av implementering av lösningsförslaget kommer bolaget uppnå spårbarhet. De rekommenderas att fortsätta utvecklingsarbetet inom spårbarhet med en organisationskultur som är lärande. / A production without traceability leads to secondary problems and extra work. in the case of complaints from several different customers where the same component is faulty or does not meet the set requirement specifications, there is a benefit in knowing in which more end products the same components from the same batch are located. Then they can be replaced, or a service package can be sent out to the customer before complications arise for the customer. Customer- and legal requirements on the ability to track critical components within medical technology to be allowed to deliver or not are existing. The traceability analysis to generate a solution proposal for the case study is based on a mixture of qualitative and quantitative data collection. Interviews and literature together with production data lay the foundation for developing a suitable solution which should be implemented. The result is to generate a basis to be able to track components. The solution is based on an in-house standardized 2-bin kanban system with FIFO (first in first out). The information is registered at all warehouse instances and follows the material through the production flow. The information that must accompany the material is date and time of arrival, supplier, quantity and article number. This needs to be implemented at all warehousing locations for the information to be included in the delivery and the end product's individual identification number. Through the analysis methods kinship tree, PICK chart and 5 why, the result has been generated. Elimination of solutions that are not currently relevant has also been highlighted in the analyzes. Comparison of flow analysis through simulation has provided a measure of how this affects production as a whole. The study can be used as the first step in a PDCA project (Plan, Do, Check, Act) where this report stands for the planning phase. Carrying through of the implementation of the solution, the company will achieve traceability. They are recommended to continue the development work in traceability with an organizational culture that is learning.
38

Séparation aveugle de mélanges linéaires de sources : application à la surveillance maritime / Blind sources separation : application to marine surveillance

Cherrak, Omar 19 March 2016 (has links)
Dans cette thèse, nous nous intéressons au système d’identification automatique spatial lequel est dédié à la surveillancemaritime par satellite. Ce système couvre une zone bien plus large que le système standard à terre correspondant àplusieurs cellules traditionnelles ce qui peut entraîner des risques de collision des données envoyées par des navireslocalisés dans des cellules différentes et reçues au niveau de l’antenne du satellite. Nous présentons différentes approchesafin de répondre au problème de collision considéré. Elles ne reposent pas toujours sur les mêmes hypothèses en ce quiconcerne les signaux reçus, et ne s’appliquent donc pas toutes dans les mêmes contextes (nombre de capteurs utilisés,mode semi-supervisé avec utilisation de trames d’apprentissage et information a priori ou mode aveugle, problèmes liés àla synchronisation des signaux, etc...).Dans un premier temps, nous proposons des méthodes permettant la séparation/dé-collision des messages en modèle surdéterminé(plus de capteurs que de messages). Elles sont fondées sur des algorithmes de décompositions matriciellesconjointes combinés à des détecteurs de points temps-fréquence (retard-fréquence Doppler) particuliers permettant laconstruction d’ensembles de matrices devant être (bloc) ou zéro (bloc) diagonalisées conjointement. En ce qui concerneles algorithmes de décompositions matricielles conjointes, nous proposons quatre nouveaux algorithmes de blocdiagonalisation conjointe (de même que leur version à pas optimal) fondés respectivement sur des algorithmesd’optimisation de type gradient conjugué, gradient conjugué pré-conditionné, Levenberg-Marquardt et Quasi-Newton. Lecalcul exact du gradient matriciel complexe et des matrices Hessiennes complexes est mené. Nous introduisonségalement un nouveau problème dénommé zéro-bloc diagonalisation conjointe non-unitaire lequel généralise le problèmedésormais classique de la zéro-diagonalisation conjointe non-unitaire. Il implique le choix d’une fonction de coût adaptéeet à nouveau le calcul de quantités telles que gradient matriciel complexe et les matrices Hessiennes complexes. Nousproposons ensuite trois nouveaux algorithmes à pas optimal fondés sur des algorithmes d’optimisation de type gradientconjugué, gradient conjugué pré-conditionné et Levenberg-Marquardt.Finalement, nous terminons par des approches à base de techniques de détection multi-utilisateurs conjointe susceptiblesde fonctionner en contexte sous-déterminé dans lequel nous ne disposons plus que d’un seul capteur recevantsimultanément plusieurs signaux sources. Nous commençons par développer une première approche par déflationconsistant à supprimer successivement les interférences. Nous proposons ensuite un deuxième mode opératoire fondéquant à lui sur l’estimateur du maximum de vraisemblance conjoint qui est une variante de l’algorithme de VITERBI. / This PHD thesis concerns the spatial automatic identification system dedicated to marine surveillance by satellite. Thissystem covers a larger area than the traditional system corresponding to several satellite cells. In such a system, there arerisks of collision of the messages sent by vessels located in different cells and received at the antenna of the samesatellite. We present different approaches to address the considered problem. They are not always based on the sameassumptions regarding the received signals and are not all applied in the same contexts (they depend on the number ofused sensors, semi-supervised mode with use of training sequences and a priori information versus blind mode, problemswith synchronization of signals, etc.). Firstly, we develop several approaches for the source separation/de-collision in theover-determined case (more sensors than messages) using joint matrix decomposition algorithms combined withdetectors of particular time-frequency (delay-Doppler frequency) points to build matrix sets to be joint (block) or zero(block) diagonalized. Concerning joint matrix decomposition algorithms, four new joint block-diagonalization algorithms(with optimal step-size) are introduced based respectively on conjugate gradient, preconditioned conjugate gradient,Levenberg-Marquardt and Quasi-Newton optimization schemes. Secondly, a new problem called non-unitary joint zeroblockdiagonalization is introduced. It encompasses the classical joint zero diagonalization problem. It involves thechoice of a well-chosen cost function and the calculation of quantities such as the complex gradient matrix and thecomplex Hessian matrices. We have therefore proposed three new algorithms (and their optimal step-size version) basedrespectively on conjugate gradient, preconditioned conjugate gradient and Levenberg-Marquardt optimization schemes.Finally, we suggest other approaches based on multi-user joint detection techniques in an underdetermined context wherewe have only one sensor receiving simultaneously several signals. First, we have developed an approach by deflationbased on a successive interferences cancelation technique. Then, we have proposed a second method based on the jointmaximum likelihood sequence estimator which is a variant of the VITERBI algorithm.
39

Formalisation d'un environnement d'analyse des données basé sur la détection d'anomalies pour l'évaluation de risques : Application à la connaissance de la situation maritime / Formalisation of a data analysis environment based on anomaly detection for risk assessment : Application to Maritime Domain Awareness

Iphar, Clément 22 November 2017 (has links)
Il existe différents systèmes de localisation de navires en mer qui favorisent une aide à la navigation et une sécurisation du trafic maritime. Ces systèmes sont également utilisés en tant qu’outils de surveillance et d’aide à la décision par les centres de surveillance basés à terre. Le Système d’Identification Automatique (AIS) déployé par l’Organisation Maritime Internationale, bien qu’étant le système de localisation de navires le plus utilisé de nos jours, est faiblement sécurisé. Cette vulnérabilité est illustrée par des cas réels et détectés tels que des usurpations d’identité ou des disparitions volontaires de navires qui sont sources de risques pour les navires, les infrastructures offshores et côtières et l’environnement.Nous proposons dans cette thèse une démarche méthodologique d’analyse et d’évaluation des messages AIS fondée sur les dimensions de la qualité de la donnée, dont l’intégrité considérée comme la plus importante de ces dimensions. Du fait de la structure complexe de l’AIS, une liste d'indicateurs a été établie, afin d’évaluer l'intégrité de la donnée, sa conformité avec les spécifications techniques du système et la cohérence des champs des messages entre eux et au sein d’un seul ou plusieurs messages. Notre démarche repose également sur l’usage d’informations additionnelles telles que des données géographiques ou des registres de navires afin d’évaluer la véracité et l’authenticité d’un message AIS et de son expéditeur.Enfin, une évaluation des risques associés est proposée, permettant une meilleurecompréhension de la situation maritime ainsi que l’établissement de liens de causalité entre les vulnérabilités du système et les risques relevant de la sécurité et sûreté de la navigation maritime. / At sea, various systems enable vessels to be aware of their environment and on the coast, those systems, such as radar, provide a picture of the maritime traffic to the coastal states. One of those systems, the Automatic Identification System (AIS) is used for security purposes (anti-collision) and as a tool for on-shore bodies as a control and surveillance and decision-support tool.An assessment of AIS based on data quality dimensions is proposed, in which integrity is highlighted as the most important of data quality dimensions. As the structure of AIS data is complex, a list of integrity items have been established, their purpose being to assess the consistency of the data within the data fields with the technical specifications of the system and the consistency of the data fields within themselves in a message and between the different messages. In addition, the use of additional data (such as fleet registers) provides additional information to assess the truthfulness and the genuineness of an AIS message and its sender.The system is weekly secured and bad quality data have been demonstrated, such as errors in the messages, data falsification or data spoofing, exemplified in concrete cases such as identity theft or vessel voluntary disappearances. In addition to message assessment, a set of threats have been identified, and an assessment of the associated risks is proposed, allowing a better comprehension of the maritime situation and the establishment of links between the vulnerabilities caused by the weaknesses of the system and the maritime risks related to the safety and security of maritime navigation.
40

A framework for an integrated student information management system for higher education in Uganda

Magara, Elisam 02 1900 (has links)
The design of any information management system (IMS) requires a clear strategy for its integration into the environment for which it is intended. Information management has been addressed in the objectives and plans of the Government of Uganda since independence in 1962, with varying degrees of success. The extensive changes that have taken place in the last few decades in Ugandan higher education have led to increased demands for managing student information. In turn a strategy for proper coordination of such data is necessary. The major aim of this study was to design such a strategy. The research therefore attempted to investigate the current state of the management and coordination of student information in Uganda. The needs and requirements of a student information management system (SIMS) and strategies for its integration in higher education programmes were established. The study carried out in the education sector was conducted using a qualitative research framework that provided a coherent set of propositions which explains the phenomenon of a SIMS. The researcher purposively selected the respondents (including key informants, administrators and student leaders) in this sector, who included people involved in the capture, storage, management and use of student information in various institutions in the given sector. Observably, the current state of the SIMS lacks a strategy to keep track of student information in Uganda. It was established that to ensure tracking of such data in the country, an identification system with standardised procedures in a coordinating structure is required together with a clear strategy for utilising the existing structures in the education sector. To design a strategy of this kind, a proposed framework for an integrated SIMS defined the principles, environment and contextual boundaries in terms of which the design is created. It defines the structure of a national student identification system and its coordination in the education sector in Uganda. Strategies for ensuring the sustainability of such a system and its implications for the socio-economic environment of higher education are considered. / Information Science / D. Lit. et Phil. (Information Science)

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