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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.
61

Sustainable Best Practices in Electronic Sector : Printed Circuit Board (PCB) Industry / Hållbar bästa praxis inom elektroniksektorns kretskortsindustri

Julius, Michelle January 2023 (has links)
Environmental issues related to the Electronic and Electrical Equipment industry lead companies to consider a new sustainability model to decouple economic growth from resource consumption and waste generation. A significant body of literature focuses on materials and process innovation in the field of Printed Circuit Board (PCB), simultaneously limited attention has been given to industry practices and circular economy strategies. This study aims to contribute insights into sustainable circular economy practices in the PCB industry; it examines the current integration of sustainability and circularity principles in PCB companies in Sweden and assesses the associated strengths, weaknesses, opportunities, and threats. Drawing on the strategies outlined in the Circular Electronic Roadmap, the study identified four main pathways relevant to design and development, procurement, and business model. The study, being exploratory and qualitative in nature, conducted semi-structured interviews with six PCB companies in Sweden. The results show that the concept of sustainability is dynamic, factors such as business nature, company size, market competitiveness, regulations, stakeholder’s expectations and priorities, and emerging frameworks are influencing the degree to which these practices are integrated into the companies. Numerous strengths include utilizing Life Cycle Analysis (LCA), adopting circular business model, sustainable technology innovation, and prioritizing environmental sustainability as an impact. Two main weaknesses are customers restriction and constrain in PCB design and upfront resource investment. Collaboration, local and regional innovation, active role of business association, and prospects for secondary market materials are discovered to serve as opportunities to advance the circular transition for companies Threats to sustainability practices include a lack of customer demand or interest, limited material information and traceability, and technical complexity of PCB. Overall, these findings could provide practical guidance for PCB companies and other stakeholders to support decision-making and actions to improve sustainability practices in the industry. / Miljöutmaningar relaterade till elektronisk- och elektrisk utrustningsindustri får företag att överväga en ny hållbarhetsmodell för att frikoppla ekonomisk tillväxt från resursförbrukning och avfallsgenerering. En betydande mängd litteratur fokuserar på material och processinnovation för tillverkningen av kretskort (eng. PCB), samtidigt som begränsad uppmärksamhet har ägnats åt industripraxis och strategier för cirkulär ekonomi. Den här studien syftar till att bidra med insikter om hållbar cirkulär ekonomi inom PCB-industrin. Den undersöker den nuvarande integrationen av hållbarhets- och cirkularitetsprinciper i PCB-företag i Sverige och bedömer associerade styrkor, svagheter, möjligheter och hot. Utifrån de strategier som beskrivs i färdplanen för cirkulär elektronik (eng. Circular Electronics Roadmap) identifierade studien fyra huvudområden som är relevanta för design och utveckling, upphandling och affärsmodell. I studien, som är explorativ och kvalitativ till sin karaktär, genomfördes semistrukturerade intervjuer med sex PCB-företag i Sverige. Resultaten visar att hållbarhetsbegreppet är dynamiskt, och att faktorer som typ av verksamhet, företagets storlek, marknadskonkurrens, regleringar, intressenternas förväntningar och prioriteringar, samt framväxande ramverk påverkar i vilken utsträckning dessa metoder integreras i företagen. Styrkor inkluderar användning av livscykelanalys (LCA), att anamma cirkulära affärsmodeller, hållbar teknikinnovation och prioritering av miljömässig hållbarhet. Två huvudsakliga svagheter är kundernas restriktioner i PCB-design samt resursinvesteringar i början av processen. Samarbete, lokal och regional innovation, aktiv roll för industriorganisationer och framtidsutsikter för återanvändning av material på den sekundära marknaden har upptäckts som möjligheter att främja den cirkulära övergången för företag. Hot inkluderar bristande efterfrågan eller intresse från kunderna, begränsad information och spårbarhet av material, samt PCB:s tekniska komplexitet. Sammantaget kan dessa resultat ge praktiska riktlinjer för PCB-företag och andra intressenter för att vägleda beslutsfattande och åtgärder för att förbättra hållbarhetsarbetet i industrin.
62

Improved Signal Integrity in IEEE 1149.1 Boundary Scan Designs

Taboada, Efren De Jesus Rangel 04 November 2004 (has links) (PDF)
This work is an analysis of solutions to problems derived from inherent timing and signal integrity issues in the use and application of the IEEE 1149.1 Standard at the board level in conjunction with its test system. Setup or hold times violations may occur in a boundary scan chain using IEEE 1149.1 compliant devices. A practical study of the TDI-TDO scan data path has been conducted to show where problems may arise in relationship to a particular board topology and test system. This work points to differences between passing and failing scan path tests for problem characterization. Serial data flow is then analyzed and suitability is discussed. Within certain conditions, a solution is proposed. This work has been shown to work on the test system. Recommendations are made based on this experimental approach.
63

A Surrogate Measure Of Customer Satisfaction In The Manufacture Of Printed Wiring Boards

Maamoun, Adam Y. 01 January 2008 (has links)
The objective of this research is to determine and develop a model that is capable of accurately measuring customer satisfaction for different industries and in particularly for the Printed Wiring Boards (PWB) Manufacturers. The new model will incorporate data not being collected or utilized by the survey method of determining customer satisfaction. The method used is a weighted average of satisfaction among several researched categories with percentages that accurately represent the relative importance of multiple facets of the PWB manufacturers customer satisfaction. A very common term in quality assurance is that "What is not measured accurately can not be evaluated or managed correctly," thus customer satisfaction is a very important aspect of any business, industry, or government. A satisfied customer will do more business and recommend it to other potential customers. Thus the business will grow and more revenues result. On the other hand, an unsatisfied customer will abandon the business and encourage more customers not to get involved with the same business so the business may decline and lose its market share and profitability. The categories that contribute to PWB customer satisfaction will be determined by conducting surveys among the leaders and best in the business of the PWB industry in addition to discovery of related articles that define the categories of the customer satisfaction for the PWB manufacturers. Once the categories are determined, the research concentrates on the weighting of the categories that most contribute to the PWB customer's satisfaction and a measure of satisfaction is derived. The model is easily applied to any other kind of PWB business or service industry. The model is based on empirical methods that will give an accurate measurement for the PWB customer's satisfaction. This in turn allows organizations the opportunity for improving customer satisfaction and increasing market share. The algorithm is based on characteristics deemed important by customers. Thus the customer satisfaction index can be computed and monitored on a regular basis without costly surveys. The major difference between this new model and the standard methods of determining customer satisfaction using the surveys is that this model will utilize data available with the proposals, sales, shipping, receiving, quality, engineering, manufacturing, and purchasing departments. The developed method to measure customer satisfaction utilizing internal data can be more cost effective, more accurate, can provide individual customer satisfaction scores, can measure whether or not these individual scores are statistically lower than the majority, and can provide satisfaction measures in real time none of which can be supplied by the survey method.
64

Dynamic response of damped attachments in fighter applications / Dynamisk respons av dämpade infästen i stridsflyg

Nordström, Katja January 2023 (has links)
This thesis investigates the impact of vibration isolators on circuit boards during harsh vibrationenvironments that occur when they are mounted on the wings of a fighter jet. To examine thisphenomenon, a mathematical model and a simulated model were developed to determine theresonant frequencies of the circuit board under various boundary conditions. Subsequently, theresonant frequencies of the circuit board were validated through experimental tests, allowing forthe establishment of the material properties of the circuit board. In order to prevent structuralfailure, this thesis employs α-gel dampers as the damped attachments for the circuit board.These vibration isolators belong to the category of silicone gel dampers and were evaluatedthrough experimental vibration testing. The two employed vibration isolators are denoted asmodels A1 and A2, exhibiting respective damping ratios of 0.1 and 0.05. By utilizing thesevibration isolators during the experimental vibration tests, the structure demonstrated resilienceagainst natural frequency coupling, thereby preventing failure. / Den här masteruppsatsen undersöker effekten av vibrationsisolatorer på kretskort under detuffa vibrationsmiljöer som sker vid vingarna på ett stridsflyg. För att undersöka detta såanvänds en matematisk modell samt en simulerad modell för att hitta resonansfekvensernaför kretskorten vid olika randvillkor. Resonansfrekvenserna från modellerna jämfördes medresonansfrekvenserna som kom tillhanda efter vibrationsprover och med dem så kunde ävenmaterialegenskaperna bestämmas. För att unvika kollaps av strukturen användes α-geldämpare till kretskorten. Dessa dämpare är gjorde av silikongel och utvärderades genomexperimentella vibrationsprover. Dessa vibrationsisolatorer var av modell A1 och A2 ochkorresponderande modell hade dämpningsförhållande 0.1 respektive 0.05. Genom att användadessa vibrationsiolatorer under de experimentella virbationstesterna så undvek strukturenkollaps genom att resonansfrekvenserna inte triggades.
65

OPERATION ASSIGNMENT WITH BOARD SPLITTING AND MULTIPLE MACHINES IN PRINTED CIRCUIT BOARD ASSEMBLY

Rakkarn, Sakchai 22 January 2008 (has links)
No description available.
66

HEURISTIC APPROACHES TO BATCHING JOBS IN PRINTED CIRCUIT BOARD ASSEMBLY

Norman, Susan K. 11 October 2001 (has links)
No description available.
67

THERMAL-ECONOMIC OPTIMIZATION AND STRUCTURAL EVALUATION FOR AN ADVANCED INTERMEDIATE HEAT EXCHANGER DESIGN

Zhang, Xiaoqin 25 October 2016 (has links)
No description available.
68

Optimization of the Assignment of Printed Circuit Cards to Assembly Lines in Electronics Assembly

Bhoja, Sudeer 28 September 1998 (has links)
The focus of this research is the line assignment problem in printed circuit card assembly systems. The line assignment problem involves the allocation of circuit card types to an appropriate assembly line among a set of assembly lines with the objective of reducing the total assembly time. These circuit cards are to be assembled in a manufacturing facility, capable of simultaneously producing a wide variety of printed circuit cards in different production volumes. A set of component types is required for each printed circuit card. The objective is to assign the circuit cards to the assembly line such that the total assembly time, which includes the setup time as well as the processing time required for all card types in a set, is minimized. The focus of this research is to develop an algorithmic strategy for addressing this problem in electronics assembly. This problem involves considering several interrelated decision problems such as assigning printed circuit cards to assembly lines, grouping circuit cards into families to reduce the number of setups, and assigning component types to machines to balance workload. The line assignment models are formulated as large scale mixed integer programming problems and are solved using a branch-and-bound algorithm, supplemented by techniques for improving the solution time. The models and solution approaches are demonstrated using industry representative data sets and can serve as useful decision support tools for process planning engineers. / Master of Science
69

Reliable On Board Data Processing System for the ICEYE- 1 satellite

Korczyk, Jakub January 2016 (has links)
Recent development in electronics for mobile devices has led to the decrease in sizes and cost of autonomous complex embedded systems such as satellites. It is now possible to build a satellite quicker and only for a fraction of previous costs by using Commercial Off The Shelf (COTS) components. Yet, there are some obstacles that need to be overcome before a successful small satellite can be designed. Among these are the radiation environment, thermal issues, the overall system complexity and tight schedules. This thesis addresses these issues and proposes an overall approach for designing small satellites’ electronics. This approach can be summarised in 6 recommendations: Keep it simple Use fast hardware iterations Do not use space grade components Use a single string design on the system level (no redundancy) Design with limited trust in the software Use simple, accessible and easy updatable documentation With respect to those recommendations an on board data processing system, the Processing Board, has been designed for the ICEYE-1 satellite. The ICEYE-1 satellite is a fully commercial Synthetic Aperture Radar (SAR) satellite that will be launched in December 2017. The designed board has been manufactured and verified during airborne test campaigns. / Nya elektronikutvecklingar för mobiltelefoner har lett till en minskning av storlek och kostnader för andra autonoma komplexa inbyggda system som t.ex. satelliter. Så kallade småsatelliter kan numera byggas snabbare och för endast en bråkdel av tidigare kostnader med hjälp av Commercial Off The Shelf (COTS) komponenter. Det finns dock vissa hinder som måste övervinnas om man vill designa en pålitligt fungerande småsatellit. Till dessa kan räknas strålningsmiljön, väl fungerande värmeledning, det totala systemets komplexitet samt snäva tidtabeller. Detta examensarbete behandlar dessa frågor och föreslår en övergripande strategi för att designa elektronik för småsatelliter. Detta tillvägagångssätt kan sammanfattas i 6 rekommendationer: Håll det enkelt Implementera snabba hårdvaruiterationer Använd inte rymdklassade komponenter Använd ingen redundans på systemnivå Designa med en begränsad tilltro på mjukvaran Dokumentera på ett enkelt, tillgängligt och lätt uppdateringsbart sätt Dessa rekommendationer har använts till att utveckla ett databehandlingssystem, kallat "Processing Board", till småsatelliten ICEYE-1. ICEYE-1 är en kommersiell Synthetic Aperture Radar (SAR) satellit som kommer att skjutas i omloppsbana i december 2017. Databehandlingssystemet i fråga har utvecklats och verifierats i samband med flygplansburna testkampanjer.
70

Application of Lamb waves using piezoelectric technique for structure health monitoring / Tillämpning av Lambvågor med hjälp av piezoelektrisk teknik för strukturhälsoövervakning

Mauritz, Simon January 2023 (has links)
Structural health monitoring (SHM) is damage detection strategy for aerospace, civiland mechanical infrastructure. This project tries to show that Lamb waves, that are being generated and sensed with piezoelectric transducers, can be used for damage detection in a SHM system. For these piezoelectric transducers to work, filtering and amplification circuits needs to be connected to them. This report include the design,simulation, assembly and testing of these circuits. Due to lack of time, it was not possible to generate and sense actual Lamb waves. The result of the thesis is thatsimulations and tests show that it is possible to generate and sense Lamb waves for damage detection in a SHM system / Structural health monitoring (SHM) är en skadedetekteringsstrategi för flyg-,civil- och mekanisk infrastruktur. Detta projekt försöker visa att Lambvågor, som genereras och avkänns med piezoelektriska givare, kan användas för skadedetektering i ett SHM-system. För att dessa piezoelektriska givare ska fungera krävs att filtrerings- och förstärkningskretsar är anslutna till dem. Denna rapport inkluderar design, simulering, montering och testning av dessa kretsar. På grund av tidsbrist var det inte möjligt att generera eller avkänna Lambvågor. Resultatet av examensarbetet är att simuleringar och tester visar att det är möjligt att generera och avkänna Lambvågor för skadedetektering i ett SHM-system.

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