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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.
21

HOW TO ACHIEVE AND ENHANCE TRACEABILITY : A study about how traceability could beimproved within manufacturing processes

Grunning, Lisa January 2019 (has links)
The trends for manufacturing organizations are continuously increased customer expectations and demands, together with globalization of both markets and competition. As we are currently approaching the fourth industrial revolution and in order to stay competitive, companies need to adopt technological changes, differentiate themselves and improve their digital maturity. In line with this, Atlas Copco Secoroc, a Swedish manufacturing company of mining equipment and tools, has shared a divisional vision stating that they will embrace the Internet of Things and introduce some of the latest technological and digital trends. This in turn, sets some requirements on a functional traceability system. This research investigates how traceability could be improved throughout Atlas Copco Secoroc’s production chain and manufacturing processes. This research is based on an empirical study consisting of observations and interviews, all conducted at the company Atlas Copco Secoroc in Fagersta, Sweden, as well as a coherent and iterative literature review. The results emphasize the importance of understanding the overall need, clearly defining a traceability strategy and setting a suitable target level. It is vital to acquire knowledge regarding the subject and to first focus on securing the internal traceability and then expand to cover the entire supply chain. Furthermore, the findings highlight existing shortcomings, present material and recommendations that should be taken into consideration before advancing further and in-dicate the synergies with total quality management. Moreover, the master thesis resulted in concrete actions regarding how Atlas Copco Secoroc can enhance traceability within their manufacturing processes. Due to confidential information these recommendations are shown to Atlas Copco only and are not included in the published master thesis. / Trenderna för tillverkande företag är ständigt ökade kundkrav och förväntningar, tillsammans med globalisering av både marknader och konkurrens. För att vara fortsatt konkurrenskraftig när vi nu närmar oss den fjärde industrirevolutionen måste företagen adaptera tekniska förändringar, differentiera sig och förbättra den digitala mognaden. I linje med detta har Atlas Copco Secoroc, ett svenskt industriföretag som tillverkar gruvutrustning och verktyg, delat en divis-ionsvision som säger att de kommer att omfamna Internet of Things och introducera några av de senaste tekniska och digitala trenderna. Detta ställer i sin tur vissa krav på ett funktionellt spårbarhetssystem. Denna studie undersöker hur spårbarheten kan förbättras genom Atlas Copco Secorocs produktionskedja och tillhörande tillverkningsprocesser. Detta examensarbete baseras på en empirisk studie utförd hos Atlas Copco Secoroc i Fagersta. Studien bestod av ingående observationer och intervjuer samt en kontinuerlig och iterativ litteraturstudie. Resultaten betonar vikten av att förstå det övergripande behovet, tydligt definiera en spårbarhetsstrategi och sätta en lämplig spårbarhetsnivå. Det är viktigt att förvärva kunskap om ämnet och att först fokusera på att säkra den interna spårbarheten innan arbetet avser täcka hela försörjningskedjan. Vidare lyfter resultaten fram befintliga brister, material och rekommendationer som bör beaktas innan en vidareutveckling kan ske. Studien presenterar även synergierna till konceptet total kvalitetsledning.Slutligen, studien har resulterat i konkreta åtgärder avseende hur Atlas Copco Secoroc kan för-bättra spårbarheten inom sina tillverkningsprocesser. På grund av konfidentiell information presenteras dessa rekommendationer endast för Atlas Copco och ingår inte i det publicerade examensarbetet.
22

Risk Cultures, Beef Traceability, and Food Safety in the United States and Zambia

Mukuni, Fidelia 15 June 2021 (has links)
Understanding ways of improving the safety of food is an important area of research. In this project, I explore the history of the food safety systems in the United States and the Republic of Zambia. Focusing on the traceability of meat (as a form of risk management), I reveal the factors shaping each of these systems, with an eye towards their similarities and differences. I argue that food safety systems come to look different due to how these regulatory systems differently define risk, some of which traceability has brought to light. In both countries, what influences risk cultures is trust in institutions, political leaders and in science and technology. For the Zambian public, trust is in local political leaders, in individuals and in brands. For the US public, trust is in information and knowledge of producers, which is found on labels. While the Zambian public generally trusts institutions, the US public, due to its history of institutional failures, does not. / Master of Science / Tracing where food comes from can be an important aspect of our food system. In this project, I show why food safety systems in the United States and Zambia look the way they that they do today. I do this by specifically focusing on how the two nations trace beef throughout the food supply chain. I show the different factors that have led to the food systems to look the way they do. My argument is that in the US and Zambia, there are non-scientific reasons why these food systems to look the way that they do today and why these countries address risk differently.
23

REQUIREMENTS TRACING USING INFORMATION RETRIEVAL

Sundaram, Senthil Karthikeyan 01 January 2007 (has links)
It is important to track how a requirement changes throughout the software lifecycle. Each requirement should be validated during and at the end of each phase of the software lifecycle. It is common to build traceability matrices to demonstrate that requirements are satisfied by the design. Traceability matrices are needed in various tasks in the software development process. Unfortunately, developers and designers do not always build traceability matrices or maintain traceability matrices to the proper level of detail. Therefore, traceability matrices are often built after-the-fact. The generation of traceability matrices is a time consuming, error prone, and mundane process. Most of the times, the traceability matrices are built manually. Consider the case where an analyst is tasked to trace a high level requirement document to a lower level requirement specification. The analyst may have to look through M x N elements, where M and N are the number of high and low level requirements, respectively. There are not many tools available to assist the analysts in tracing unstructured textual artifacts and the very few tools that are available require enormous pre-processing. The prime objective of this work was to dynamically generate traceability links for unstructured textual artifacts using information retrieval (IR) methods. Given a user query and a document collection, IR methods identify all the documents that match the query. A closer observation of the requirements tracing process reveals the fact that it can be stated as a recursive IR problem. The main goals of this work were to solve the requirements traceability problem using IR methods and to improve the accuracy of the traceability links generated while best utilizing the analysts time. This work looked into adopting different IR methods and using user feedback to improve the traceability links generated. It also applied wrinkles such as filtering to the original IR methods. It also analyzed using a voting mechanism to select the traceability links identified by different IR methods. Finally, the IR methods were evaluated using six datasets. The results showed that automating requirements tracing process using IR methods helped save analysts time and generate good quality traceability matrices.
24

Automatic Generation of Trace Links in Model-driven Software Development

Grammel, Birgit 02 December 2014 (has links) (PDF)
Traceability data provides the knowledge on dependencies and logical relations existing amongst artefacts that are created during software development. In reasoning over traceability data, conclusions can be drawn to increase the quality of software. The paradigm of Model-driven Software Engineering (MDSD) promotes the generation of software out of models. The latter are specified through different modelling languages. In subsequent model transformations, these models are used to generate programming code automatically. Traceability data of the involved artefacts in a MDSD process can be used to increase the software quality in providing the necessary knowledge as described above. Existing traceability solutions in MDSD are based on the integral model mapping of transformation execution to generate traceability data. Yet, these solutions still entail a wide range of open challenges. One challenge is that the collected traceability data does not adhere to a unified formal definition, which leads to poorly integrated traceability data. This aggravates the reasoning over traceability data. Furthermore, these traceability solutions all depend on the existence of a transformation engine. However, not in all cases pertaining to MDSD can a transformation engine be accessed, while taking into account proprietary transformation engines, or manually implemented transformations. In these cases it is not possible to instrument the transformation engine for the sake of generating traceability data, resulting in a lack of traceability data. In this work, we address these shortcomings. In doing so, we propose a generic traceability framework for augmenting arbitrary transformation approaches with a traceability mechanism. To integrate traceability data from different transformation approaches, our approach features a methodology for augmentation possibilities based on a design pattern. The design pattern supplies the engineer with recommendations for designing the traceability mechanism and for modelling traceability data. Additionally, to provide a traceability mechanism for inaccessible transformation engines, we leverage parallel model matching to generate traceability data for arbitrary source and target models. This approach is based on a language-agnostic concept of three similarity measures for matching. To realise the similarity measures, we exploit metamodel matching techniques for graph-based model matching. Finally, we evaluate our approach according to a set of transformations from an SAP business application and the domain of MDSD.
25

Integrity and Security Considerations of Transparency and Traceability : an Exploratory Case Study of Traceability Validation Systems

Löwenhav, Caroline, Tingsvik, Hanna January 2022 (has links)
Background: In recent years, unfair and unsafe working conditions have been reported, raising concerns among stakeholders and end-users. The demand for fashion brands to take further responsibility for social sustainability and transparency has increased. Providing complete transparency can be one solution to these issues, and traceability validation systems can be used to achieve complete transparency, covering the supply chain's social aspects. A research gap was found linking the concepts of transparency, traceability, the social aspects of sustainability, including integrity and security of the supply chain actors, and validation systems. Purpose: Therefore, the purpose of this study is to explore traceability validation systems within the TA supply chain from a social perspective, specifically the integrity and security of SCAs. Methodology: An exploratory case study was conducted, including in-depth interviews with eleven respondents representing different supply chain actors and experts in the textile and apparel industry. Data were also collected through a survey and questions over email. Focus Company: The focus company for this study, PaperTale, is a start-up company that offers a blockchain-based traceability solution that enables textile and apparel companies to track and trace their supply chain via an application. Through the PaperTale app, the end-user can receive information about the garment by scanning the NFC tag or QR code attached to the garment. The PaperTale system is an example of what is defined as a traceability validation system in this study. Findings & Analysis: In general, the experiences of the respondent that has been involved in the PaperTale app was good. Some reluctance has been encountered while sharing information that can be connected to cultural aspects and lack of incentives. Overall, the impact on the different supply chain actors is good and includes making more profit for both brands and suppliers and incentivising the workers. However, the imbalance of profit and time distribution was brought up. To provide security and reliance to the supply chain actors while sharing information to a traceability validation system, the respondent emphasised the importance of union protection, legislation, and third-party validation. Lastly, most respondents are optimistic about using a third party to validate the transparency and traceability data added to the traceability validation system. Implications & Suggestions for Future Research: The contribution of this study is an increased understanding of the social aspects of transparency and traceability on a general level. Furthermore, it contributes to a deeper description and understanding of how traceability validation systems can affect and impact textile and apparel supply chain actors. The study also highlights opportunities and challenges with the system that provides direction in research. Traceability validation systems are a somewhat new topic. Many questions remain regarding who has the highest responsibility for entering data and how the system can be used on a large scale
26

A Domain-Specific Language for Traceability in Modeling

Rahman, Anisur 24 July 2013 (has links)
Requirements are a key aspect of software development. Requirements are also related with other software artefacts including designs, test cases and documentation. These artefacts are often captured with specialized models. However, many tools lack support for traceability relationships between requirements artefacts and model artefacts, leading to analysis issues. To establish traceability between models and other types of requirements artefacts, this thesis proposes a new Domain-Specific Language (DSL) for describing the concepts of a modeling language that would be intended to be traced using a Requirements Management System (RMS), with tool support handling the evolution of models and of their traceability links. In the first part of this thesis, the syntax and metamodel of the Model Traceability DSL (MT-DSL) are defined, together with an editor implemented using Xtext. In the second part of the thesis, a library of import and maintenance functions is generated automatically (using Xtend) from model traceability descriptions written using MT-DSL. The target language for this library is the DOORS eXtension Language (DXL), the scripting language of a leading commercial RMS with traceability support, namely IBM Rational DOORS. The implementation has been tested successfully for importing and evolution scenarios with two different modeling languages (User Requirements Notation and Finite State Machines). This work hence contributes a reliable mechanism to define and support traceability between requirements and models.
27

A Domain-Specific Language for Traceability in Modeling

Rahman, Anisur January 2013 (has links)
Requirements are a key aspect of software development. Requirements are also related with other software artefacts including designs, test cases and documentation. These artefacts are often captured with specialized models. However, many tools lack support for traceability relationships between requirements artefacts and model artefacts, leading to analysis issues. To establish traceability between models and other types of requirements artefacts, this thesis proposes a new Domain-Specific Language (DSL) for describing the concepts of a modeling language that would be intended to be traced using a Requirements Management System (RMS), with tool support handling the evolution of models and of their traceability links. In the first part of this thesis, the syntax and metamodel of the Model Traceability DSL (MT-DSL) are defined, together with an editor implemented using Xtext. In the second part of the thesis, a library of import and maintenance functions is generated automatically (using Xtend) from model traceability descriptions written using MT-DSL. The target language for this library is the DOORS eXtension Language (DXL), the scripting language of a leading commercial RMS with traceability support, namely IBM Rational DOORS. The implementation has been tested successfully for importing and evolution scenarios with two different modeling languages (User Requirements Notation and Finite State Machines). This work hence contributes a reliable mechanism to define and support traceability between requirements and models.
28

APPLICATION OF SWARM AND REINFORCEMENT LEARNING TECHNIQUES TO REQUIREMENTS TRACING

Sultanov, Hakim 01 January 2013 (has links)
Today, software has become deeply woven into the fabric of our lives. The quality of the software we depend on needs to be ensured at every phase of the Software Development Life Cycle (SDLC). An analyst uses the requirements engineering process to gather and analyze system requirements in the early stages of the SDLC. An undetected problem at the beginning of the project can carry all the way through to the deployed product. The Requirements Traceability Matrix (RTM) serves as a tool to demonstrate how requirements are addressed by the design and implementation elements throughout the entire software development lifecycle. Creating an RTM matrix by hand is an arduous task. Manual generation of an RTM can be an error prone process as well. As the size of the requirements and design document collection grows, it becomes more challenging to ensure proper coverage of the requirements by the design elements, i.e., assure that every requirement is addressed by at least one design element. The techniques used by the existing requirements tracing tools take into account only the content of the documents to establish possible links. We expect that if we take into account the relative order of the text around the common terms within the inspected documents, we may discover candidate links with a higher accuracy. The aim of this research is to demonstrate how we can apply machine learning algorithms to software requirements engineering problems. This work addresses the problem of requirements tracing by viewing it in light of the Ant Colony Optimization (ACO) algorithm and a reinforcement learning algorithm. By treating the documents as the starting (nest) and ending points (sugar piles) of a path and the terms used in the documents as connecting nodes, a possible link can be established and strengthened by attracting more agents (ants) onto a path between the two documents by using pheromone deposits. The results of the work show that ACO and RL can successfully establish links between two sets of documents.
29

Une solution tolérante aux délais pour des applications de localisation et de traçabilité a posteriori en milieux confinés / A tolerant solution to deadlines for tracking and traceability applications post in confined spaces

Baouche, Mohamed Chakib 12 July 2012 (has links)
Cette thèse porte sur l’exploitation d’une population nomade afin de colporter des informations dites ‘atomiques’ de rencontres entre entités fixes ou mobiles pour des applications diverses basées sur la localisation et la traçabilité. Répondre à ces besoins en milieux confinés s’avère un défi, que ce soit dans un contexte industriel, médical ou social. Parmi les solutions existantes, le système GPS (Global Positioning System) offre des résultats encourageants lorsqu’il s’agit de connaître une position en extérieur. Cette solution n’est plus utilisable en intérieur tel que dans une mine par exemple, en raison des caractéristiques du signal fortement perturbées dans ce type de milieu. Le fil directeur de ce travail consiste à proposer un modèle utilisant la technologie des réseaux de capteurs sans fil afin de modéliser et de trouver des solutions à des problématiques allant de la localisation en milieux confinés au suivi et à la reconstitution de trajectoires d’entités mobiles. Les solutions proposées dans cette thématique doivent être tolérantes aux délais. Après avoir présenté les constituants de notre modèle générique de colportage, une instanciation de ce modèle a permis de nous pencher sur un cas de localisation et de traçabilité dans un espace confiné. Les résultats de simulation et d’expérimentation ont montré l’impact de notre mécanisme de colportage sur la qualité de l’information recensée concernant les déplacements et les rencontres des entités mobiles. Outre la proposition d’un modèle générique, la contribution de cette thèse comporte des mécanismes de colportage (et de filtrage) de l’information par des entités mobiles contraintes en taille mémoire. / This thesis focuses on the exploitation of a nomadic population to pass around information called contact event which represents the recording of a meeting between fixed or mobile entities for localization and tracking applications. Addressing these needs in confined environments is a challenge, whether in an industrial, medical or social context. Among the existing solutions, the GPS (Global Positioning System) provides encouraging results for outdoor localization. However, this solution is not operational in confined environments such as mines, due to the signal characteristics highly disturbed in this type of environment. The guiding principle of this work is to propose a model using the technology of wireless sensor networks for modeling and finding solutions for localization and tracking mobile nodes in confined areas. The new approach proposed in this thesis is inspired by the principle of ‘store-carry-forward’ of Delay-Tolerant-Network (DTN). After presenting the components of our generic model, an instantiation of this model has allowed us to address a localization and tracking case in a confined area. The simulation and experimentation results show the impact of our filtering mechanism on the quality of the knowledge collected concerning the movements and meetings of the mobile nodes.
30

Calibração de acelerômetros / Calibration of accelerometers

Azevedo, José Cláudio Pinto de 24 October 2003 (has links)
Este trabalho apresenta o projeto e desenvolvimento de dois sistemas de calibração de acelerômetros. O primeiro sistema foi desenvolvido a partir de um sistema interferométrico laser Hewlett-Packard (HP 5529A), utilizado como padrão de referência absoluta. Este sistema foi projetado com o propósito de calibrar acelerômetros-padrão de comparação e acelerômetros-padrão de transferência. O segundo sistema de calibração utiliza como padrão de referência acelerômetros-padrão de comparação. Este segundo sistema foi projetado com o objetivo de calibrar acelerômetros de uso corriqueiro. Desta forma, o conjunto formado pelos dois sistemas de calibração podem ser rastreáveis até os padrões primários, nacionais e internacionais. Para cada um dos sistemas de calibração são apresentadas discussões relativas às suas características construtivas, aos testes de operação e às avaliações sobre os desempenhos alcançados. / This work presents the design and development of two accelerometer calibration systems. The first system was developed from a Hewlett-Packard laser interferometric system (HP 5529A), taken as an absolute reference standard. This system was designed to allow calibration of comparison standard accelerometers and transfer standard accelerometers. The second calibration system, which employs comparison standard accelerometers as reference, was designed to calibrate common use accelerometers. Thus, the arrangement of the two calibration systems can be traceable until the primary national and international standards. For each calibration system, a discussion is presented, concerning their constructive characteristics, operation testing and evaluation of accomplished performance.

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