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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.
1

Analysis of clean room conditions impact on labor productivity : case study

Woo, Jeyoung 18 June 2012 (has links)
The semiconductor industry follows what is known as Moore’s Law. Moore’s Law says that every 18 months computer chip storage capacity doubles and the intervals between developments in chip design become shorter and shorter. This is also true for the set dates for construction which are dictated by the semiconductor industry’s needs and production schedule. This paper analyzes the impact of a clean room environment. It scrutinizes daily reports and interviews, based on two data sets that focus on a semiconductor wafer fabrication facility (FAB) construction project. Both data sets involve the same crew working on a FAB construction project in the U.S. Room conditions, however, differ. Aside from such working conditions, all elements for both groups are the same (crew skill level, weather, and season). This research is based on the installation, from February 2010 to January 2011 in Austin, Texas, of an access floor in a semiconductor FAB construction project. The total cost of the project was US$3.6 billion. Generally, a semiconductor FAB has raised access floors because cables and pipes are laid under the floors for maintenance and operation purposes. The data for this paper is derived from the access floor installation. The project manager’s daily progress record documented the changes in labor productivity. The data on the number of crew and work-hours is computed based on this information. Labor productivity is defined here as the relationship between output and the labor time for its production. The formula is as follows: Labor productivity = Output(Quantity) / Input(Work-hours) Eq. (1) This study used Eq. (1) to measure labor productivity for two conditions (working in general conditions and working in a clean room conditions). Labor productivity was computed as follows: the unit of output (quantity) is sq. ft., and the unit of input (work-hours) is hours. The questionnaires and interviews attempted to identify the factors affecting project performance: rework, crew interference, overcrowded work areas, and overtime (Garner, et al., 1979; Tucker, et al., 1980). Each section consisted of yes/no questions and one question seeking the interviewee’s opinion about how each problem was solved. The responses are summarized as follows: The results indicate that, in the clean room environment, labor productivity fell by 28.85%. For future projects, this drop represents additional time and money that should be taken into account in the estimate of costs and the schedule duration. The interviews indicate that labor productivity was affected by other factors such as rework, tool availability, other crews not being finished, overcrowded work areas, as well as access to work area. / text
2

The Analysis of Air Flow Pattern For Pollution Control

Wu, Yu-ping 19 June 2002 (has links)
In recent years, the demand for higher cleanliness and air quality control of the indoor environment is increasing especially during the manufacturing process. Although different design standards and codes were adapted worldwide, the air flow pattern analysis still dominates the design process. The parameters affecting the design process were cross-examined, including the air change rate, clean room sizes and layout, air supply and exhaust ports layout, unbalanced supply and exhaust air volume (QR=1.2QS), until system optimization is achieved. Furthermore, FFU system with 0.46m/s air speed was identified to be appropriate for injection module designs. In order not to increase manufacturing cost, the FFU can be design with three-fiered speed control to provide energy efficiency with space flexibility. However, in low-speed operation, the slightly positive pressure cannot be maintained properly and should be avoided to operate in unconditioned rooms.
3

An investigation and examination of the levels and types of bacterial contamination on the surface of clean room operators' garments

Smith, Laurie McKenzie January 2018 (has links)
The contamination of sterile pharmaceutical products is a serious event which has in the worst case scenario led to patient death. Operators are the primary source of clean room contamination, with the majority of their detritus being identified as skin squames and their related microorganisms. The ability of operator associated bacterial contamination to disseminate through specialist garments worn in the clean room environment is apparent in the literature. However, despite the fibres of such garments being identified as a suitable substrate for bacteria to adhere to and grow upon, the bacterial bioburden of the surface of clean room operators’ garments is an area which severely lacks in published research. Reported here is the recovery, enumeration and comparison of the levels of bacteria on the surface of reusable antistatic carbon filament polyester clean room garments, using the direct agar contact method, following their laundering with and without terminal gamma sterilisation, immediately following their donning with operators dressing wearing either no gloves, non – sterile gloves or sterile clean room gloves, and following their wear within the clean room environment, with respect to gender. The aforementioned method, with its recovery efficiency shown to be unaffected by agar composition (NA or TSA), recovered bacteria from the surface of garments laundered with and without gamma sterilisation. Such terminal decontamination was shown to reduce the surface bacterial bioburden of the garments, especially at the chest and umbilicus regions, which were shown to harbour higher levels of bacteria than the other sites tested. The direct agar contact method, showing an increase in recovery efficiency following a 48 hour agar incubation period as opposed to a 24 hour period, also recovered bacteria from the surface of clean room garments donned by operators dressing wearing either no gloves, non – sterile gloves and sterile clean room gloves. Bacteria were transferred onto the surface of these garments via the hand borne route, with the chest and oral cavity regions being found to harbour more bacteria than the other sites tested. Overall, glove type was shown to have no effect upon the resultant bacterial bioburden of the surface of the garments, suggesting expensive clean room gloves could be substituted for their cheaper non – sterile equivalents or no gloves during the donning process without subsequently increasing the surface bacterial bioburden of the garment. The direct agar contact method also recovered bacteria from the surface of clean room garments worn by male and female operators, following their working period within a clean room environment. Gender was found to significantly affect the surface bacterial bioburden of the garments, with the surface of those garments worn by male operators being more contaminated than the surface of those worn by their female counterparts. In addition, the donning of a clean room hood was shown to reduce the levels of bacteria at the chest and posterior cervicis regions of suits worn by both genders. Overall, the direct agar contact method was identified as a successful tool to recover, enumerate and estimate the surface bacterial bioburden of reusable antistatic polyester carbon filament clean room garments. Finally, using 16S rRNA gene sequencing, found to be more reliable and accurate at identifying unknown isolates than traditional phenotypic first - stage tests, which were subsequently found to misidentify > 85 % of the isolates tested, a self - selected representative number of isolates recovered from the surface of garments during the laundering and gender comparison studies were predominantly identified as skin commensal species of Staphylococcus and Micrococcus, as well as environmental species of Bacillus. The knowledge contained within this thesis, with respect to clean room operators and their specialist garments, contributes towards improving contamination control standards within clean room facilities.
4

Demontering av ett mekaniskt låssystem med CAN 2.0 : En fallstudie i hur en CAN-buss kan användas inom dörrlåssystem

Hassan, Mahad, Edelsvärd, Fredrik January 2020 (has links)
Låssystem kan minska risken för inbrott och stöld, och vara ett verktyg för behöriga personer att få tillgång till lokaler och rum. Därför är det viktigt att moderna låssystem är pålitliga, öppnar snabbt och är säkra. Detta examensarbete undersöker om CAN (Controller Area Network) är ett idealt kommunikationsprotokoll för ett säkerhetssystem av dörrlås, med syftet att utföra en fallstudie av CAN-protokollet. Detta sker genom att analysera ett låssystem från ASSA vars kommunikationsprotokoll mellan styroch låsenhet misstänktes använda CAN-protokollet mellan dess styrenhet och låsenhet. Slutsatsen av analysen var att låssystemet från ASSA inte kommunicerade via CAN. För att bevisa dettaåterskapades signaler med elektriska standardinterface RS-485. Det sista steget vara att utveckla ett eget låssystem med CAN som kommunikationsprotokoll, och sedan skulle de två låssystem jämföras. För att testa detta programmeras två kretskort av typen ESP32-PoE till en styrenhet och en låsenhet. Ett låssystem designades på ett kopplingsdäck innan den ersattes av två PCBs. Slutresultatet var ett motorlås och en styrenhet som konstruerades och validerades i ett kopplingsdäck. Av de två kretskorten som utvecklades fungerade kontrollenheten som förväntat, medan låsenheten hade problem med dess motor. Den kunde dock klara av dess andra uppgifter som att läsa signaler från styrenheten via en 10 meter kabel och läsa signaler från dess dörrläge givande magnetsensor. Det demonterade låssystemet sänder signaler snabbare, och öppnar låset ungefär lika snabbt, men är inte lika säker som den kommersiella låssystemet för att CAN har restriktiva säkerhetsåtgärder. / Lock systems can reduce the risk of burglary and theft, and be a tool for authorized persons to access premises and rooms. Therefore, it is important that modern lock systems are secure, reliable and open quickly. This thesis investigates whether CAN (Controller Area Network) is an ideal communication protocol for a door lock security system. This is done by analyzing a mechanical lock system from ASSA which was suspected of using CANbus as a communication protocol between the control unit and lock unit. Then the lock and control units were analyzed. The conclusion of the analysis is that the lock system did not communicate via CAN. To prove this, signals were re-created with the electrical standard interface RS-485.The final step was to construct a lock system with CAN as a communication protocol, and then the two lock systems would be compared.To test this, two ESP32-PoE development boards are programmed into a controller and a locking device. A mechanical door lock system was designed on a breadboard before being replaced by two PCBs. Of the two circuit types that were developed, the control unit worked as expected, while the motorlock unit had problems with it’s motor. However, it was able to handle its other tasks such as reading signals from the controller via a 10 meter cable and reading signals from its door locating magnetic sensor. The disassembled lock system sends signals faster, and opens the lock approximately as quickly, but is not as secure as the commercial CAN lock system has restrictive security measures.
5

Estudo para minimização do processo de fumigação empregado na limpeza e desinfecção de salas limpas em Bio-Manguinhos/ FIOCRUZ / Study for minimization of the process of fumigation used in the cleanness and disinfection of clean rooms in Bio-Manguinhos/FIOCRUZ

Stella Martins Patitucci 16 January 2008 (has links)
As indústrias farmacêuticas que utilizam salas limpas, em seus processos produtivos, devem controlar ao máximo o nível de contaminantes microbiológicos, baseada na legislação RDC 210 que determina o cumprimento das diretrizes estabelecidas no Regulamento Técnico das Boas Práticas para a Fabricação de Medicamentos. Diante deste cenário, a proposta deste trabalho é avaliar o processo de fumigação com o reagente formaldeído, para a limpeza e desinfecção de salas limpas do Instituto de Tecnologia de Imunobiológicos Bio-Manguinhos. Então, foram desenvolvidas as seguintes etapas: diagnóstico com as indústrias farmacêuticas para traçar um perfil quanto ao uso da fumigação; quantificação de resíduos gerados; avaliação da exposição dos operadores ao formaldeído que é cancerígeno e acompanhamento dos resultados do monitoramento ambiental do ar e de superfícies, inicialmente na sala limpa do SEFBC, cuja atividade principal é a formulação de vacinas bacterianas e biofármacos, após a implantação do espaçamento da fumigação. Os resultados discutidos na presente dissertação mostraram, que a maior parte das indústrias farmacêuticas, não realiza a desinfecção por intermédio da fumigação e que o resíduo gerado neste processo é o mais crítico. E, sobretudo, o monitoramento microbiológico do ar e de superfícies da sala limpa do SEFBC, a partir da metodologia adotada de espaçamento da fumigação, comprovou que não é necessário o emprego deste processo de forma rotineira, para garantir os níveis exigidos de limpeza e desinfecção da respectiva área / Pharmaceutical industries that use clean rooms for their productive processes, must control to a maximum the level of microbiological contaminants, based on RDC 210 legislation that determines the fulfillment of lines in the directions established by the Technical Regulation Program for a Good Medicine Manufacturing. Ahead to this scene, the purpose of this work was to evaluate the process of fumigation with reacting formaldehyde, for the cleanness and disinfection of clean rooms of the Bio-Manguinhos Institute of Technology of Imunobiológicos. Then, the following stages had been developed: diagnosis with the pharmaceutical industries in order to get a scenario on the use of fumigation; quantification of the residues generated; evaluation of the exposition of operators to formaldehyde, a cancerigenous agent, and screening of the results of the environment monitoring of the air and surfaces, initially in the clean room of the SEFBC, in the areas of biopharmaceuticals formulation, and after a proper implementation of a fumigation process, at pre-defined intervals. The results thus obtained showed that most of the pharmaceutical industries no longer use disinfection for fumigation and that the residues generated in this process is the most critical problem. The overall microbiological monitoring of the air and surfaces of SEFBC clean room, according to the proposed methodology for fumigation, proved that the use of this process as a routine is not essential to guarantee the demanded levels of cleanness and disinfection of the respective areas
6

Estudo para minimização do processo de fumigação empregado na limpeza e desinfecção de salas limpas em Bio-Manguinhos/ FIOCRUZ / Study for minimization of the process of fumigation used in the cleanness and disinfection of clean rooms in Bio-Manguinhos/FIOCRUZ

Stella Martins Patitucci 16 January 2008 (has links)
As indústrias farmacêuticas que utilizam salas limpas, em seus processos produtivos, devem controlar ao máximo o nível de contaminantes microbiológicos, baseada na legislação RDC 210 que determina o cumprimento das diretrizes estabelecidas no Regulamento Técnico das Boas Práticas para a Fabricação de Medicamentos. Diante deste cenário, a proposta deste trabalho é avaliar o processo de fumigação com o reagente formaldeído, para a limpeza e desinfecção de salas limpas do Instituto de Tecnologia de Imunobiológicos Bio-Manguinhos. Então, foram desenvolvidas as seguintes etapas: diagnóstico com as indústrias farmacêuticas para traçar um perfil quanto ao uso da fumigação; quantificação de resíduos gerados; avaliação da exposição dos operadores ao formaldeído que é cancerígeno e acompanhamento dos resultados do monitoramento ambiental do ar e de superfícies, inicialmente na sala limpa do SEFBC, cuja atividade principal é a formulação de vacinas bacterianas e biofármacos, após a implantação do espaçamento da fumigação. Os resultados discutidos na presente dissertação mostraram, que a maior parte das indústrias farmacêuticas, não realiza a desinfecção por intermédio da fumigação e que o resíduo gerado neste processo é o mais crítico. E, sobretudo, o monitoramento microbiológico do ar e de superfícies da sala limpa do SEFBC, a partir da metodologia adotada de espaçamento da fumigação, comprovou que não é necessário o emprego deste processo de forma rotineira, para garantir os níveis exigidos de limpeza e desinfecção da respectiva área / Pharmaceutical industries that use clean rooms for their productive processes, must control to a maximum the level of microbiological contaminants, based on RDC 210 legislation that determines the fulfillment of lines in the directions established by the Technical Regulation Program for a Good Medicine Manufacturing. Ahead to this scene, the purpose of this work was to evaluate the process of fumigation with reacting formaldehyde, for the cleanness and disinfection of clean rooms of the Bio-Manguinhos Institute of Technology of Imunobiológicos. Then, the following stages had been developed: diagnosis with the pharmaceutical industries in order to get a scenario on the use of fumigation; quantification of the residues generated; evaluation of the exposition of operators to formaldehyde, a cancerigenous agent, and screening of the results of the environment monitoring of the air and surfaces, initially in the clean room of the SEFBC, in the areas of biopharmaceuticals formulation, and after a proper implementation of a fumigation process, at pre-defined intervals. The results thus obtained showed that most of the pharmaceutical industries no longer use disinfection for fumigation and that the residues generated in this process is the most critical problem. The overall microbiological monitoring of the air and surfaces of SEFBC clean room, according to the proposed methodology for fumigation, proved that the use of this process as a routine is not essential to guarantee the demanded levels of cleanness and disinfection of the respective areas
7

Adaptação e avaliação de desempenho de sistema asseptico para leite fluido em garrafa plastica / Adaptation and evaluation of performance of aseptic system for fluid milk in plastic bottle

Petrus, Rodrigo Rodrigues 17 December 2004 (has links)
Orientador: Jose de Assis Fonseca Faria / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos / Made available in DSpace on 2018-08-04T01:05:22Z (GMT). No. of bitstreams: 1 Petrus_RodrigoRodrigues_D.pdf: 1772681 bytes, checksum: a2e739a7a3e2168d1c5de3ebe70fed22 (MD5) Previous issue date: 2004 / Resumo: O objetivo desta pesquisa consistiu na adaptação e avaliação do desempenho de um sistema asséptico piloto para leite fluido em garrafa plástica. O sistema foi avaliado através da identificação e monitoração sistemática de pontos de controle do processo, testes de esterilidade comercial, análises sensorial e físico-química do produto e avaliação da embalagem. Os pontos de controle foram monitorados antes e simultaneamente aos processamentos, a saber: tratamento térmico do leite; conformidade operacional da sala de envase, incluindo pressurização, taxa de movimentação de ar, contagem de partículas totais e microrganismos no ar e avaliação de limpeza e sanificação de superfícies; análise microbiológica da água de enxágüe da linha de processamento e envase, análise das embalagens e de sua água de enxágüe. Quatro lotes de 150L de leite com pH próximo a 6,7 foram processados entre 135 a 144ºC durante 10s em um trocador de calor a placas e acondicionados assepticamente em garrafas de polietileno de alta densidade (PEAD) de 500mL, em uma sala limpa ISO classe 7. A assepsia das embalagens foi feita através de aspersão de uma mistura contendo 0,5% de ácido peracético e 0,8% de peróxido de hidrogênio a 30ºC/10s. O leite processado através do sistema asséptico piloto avaliado foi comparado ao leite longa vida comercial em embalagens cartonadas e em garrafas plásticas de PEAD de alta barreira, aplicando-se testes de aceitação sensorial. Os resultados da avaliação dos pontos de controle do processo indicaram um bom desempenho apresentado pelo sistema desenvolvido, justificado pelas baixas contagens ou ausência de microrganismos nos pontos avaliados. Dos 4 lotes processados, 2 atingiram a esterilidade comercial, baseado nos critérios físico-químicos e microbiológicos adotados. A vida útil do produto, estimada através de testes sensoriais, atingiu 4 semanas para os dois primeiros lotes produzidos, 8 semanas para o lote 3 e 11 semanas para o lote 4. A opacidade das embalagens utilizadas na pesquisa foi de 90%, inferior a opacidade das embalagens comerciais, que foi de 100%. Portanto, a barreira à luz foi considerada insuficiente para a embalagem em avaliação, em virtude da elevada sensibilidade do leite à fotoxidação. Concluiu-se que o sistema asséptico piloto avaliado correspondeu às expectativas de desempenho, devendo, entretanto, ser submetido à implementação de melhorias em sua infra-estrutura para que possa ser eventualmente disponibilizado para processamentos em pequena escala, visando a produção de leite comercialmente estéril acondicionado em garrafas plásticas / Abstract: The objective of this research was the adaptation and performance evaluation of a pilot aseptic system for liquid milk filled into plastic bottles. The system was evaluated by identifying and systematically monitoring the process control points, by commercial sterility tests, sensory, physical and chemical analyses of the product and an evaluation of the packaging. The control points were monitored before and during process as follows: heat treatment of the milk; operational conformity during filling in the aseptic room including pressurization, air movement rate, total and viable particle count and evaluation of surface cleanliness and sanitation; microbiological analyses of the rinsing waters used in the process and filling lines and an analysis of the packages and their rinsing water. Four 150L batches of milk with pH values of about 6.7 were heat processed between 135 and 144°C for 10s in a plate heat exchanger and filled aseptically into 500mL high density polyethylene (HDPE) bottles in an ISO class 7 clean room. The aseptic condition of the bottles was obtained by spraying with a mixture containing 0.5% peracetic acid and 0.8% hydrogen peroxide for 10s at 30°C. The processed milk using the pilot aseptic system was compared by sensory analysis with commercial long life milk filled into carton-type packages and plastic bottles. The results of the microbial evaluation of the control points indicated good performance of the system developed based on the low counts and absence of microorganisms at some evaluated points. Of the 4 batches processed, 2 attained commercial sterility based on the physical-chemical and microbiological criteria adopted. The shelf life of the product, estimated according to the sensory tests, was 4 weeks for the first two batches processed, 8 for batch 3 and 11 for batch 4. The opacity of the packaging used was 90%, lower than that of commercial packaging, which was 100%. Thus the light barrier property was considered inadequate considering the high sensitivity of milk to the photooxidation. It was concluded that the pilot aseptic system evaluated corresponded to the performance expectations, however, it should be submitted to some implementations of improvements in its infrastructure in order to be recommended for small-scale commercially ile milk production / Doutorado / Doutor em Tecnologia de Alimentos
8

Vzduchotechnika pro technologické čisté prostory / Air conditioning in Cleanrooms for Technology

Adamec, Jan January 2014 (has links)
The main objective of this thesis is to propose and evaluate two variants of HVAC systems for clean rooms. The proposed system is pressurized. As part of the experimental section in which the data obtained are evaluated - humidity and air temperature.
9

Intégration d'oxydes fonctionnels pour applications en photonique / Integration of functional oxides for photonic applications

Marcaud, Guillaume 05 December 2018 (has links)
Le 21ème siècle est marqué par une nouvelle ère du numérique, notamment due au développement d’objets connectés toujours plus nombreux et variés. L’incroyable croissance, du flux de données produites, échangées et stockées au niveau mondial, a permis l’émergence de nouvelles technologies comme la photonique silicium. Cette dernière est cependant limitée par les propriétés intrinsèques du silicium, comme son gap indirect et sa structure cristalline centro-symétrique.En parallèle, la famille des oxydes fonctionnels présente une incroyable diversité de propriétés, comme la ferroélectricité ou la piézoélectricité. Leur intégration en photonique est principalement limitée par l’épitaxie sur silicium. En effet, la différence de paramètre de maille entre la plupart des oxydes et le silicium engendre une grande quantité de défauts et donc une forte dégradation de leurs propriétés. L’oxyde de zirconium stabilisé à l’yttrium (YSZ), qui présente un paramètre de maille intermédiaire, assure la transition entre les réseaux cristallins. Ce travail de thèse s’articule ainsi autour de la croissance d’YSZ et la caractérisation de ses propriétés en optique intégrée.Dans un premier temps, nous avons étudié la croissance d’YSZ par ablation laser pulsé (PLD), ainsi que la fabrication et caractérisation de structures photoniques sur substrat de saphir. Nous avons mis en évidence le rôle du recuit du substrat avant dépôt, sur l’orientation et la qualité du film. L’optimisation du dépôt et le développement d’un procédé de fabrication, a permis la démonstration de guides d’onde à faibles pertes, d’environs 2 dB/cm, et de composants passifs plus complexes comme des structures résonantes en anneau, micro-disques et filtres de Bragg. Nous avons également caractérisé les propriétés optiques non-linéaires du troisième ordre de l’YSZ dont les résultats expérimentaux ont été confirmés par des calculs théoriques. La valeur de l’indice de réfraction non-linéaire n2, de l’YSZ, est comparable à celle du nitrure de silicium (SiN), déjà utilisé comme matériau non-linéaire.En raison de la différence de paramètre de maille et du coefficient d’expansion thermique, l’intégration d’YSZ est susceptible d’induire de larges contraintes dans le silicium, et de briser sa centro-symétrie. De récentes études, expérimentales et théoriques, ont démontré que les contraintes permettent d’exploiter des propriétés optiques non-linéaires d’ordre deux dans le silicium, normalement inexistantes dans ce matériau. Pour caractériser la distribution des contraintes, vues par un mode optique se propageant dans un guide d’onde silicium, nous avons mis en place une nouvelle technique expérimentale basée sur l’effet Raman en optique intégrée. Des signatures d’évolutions de phonons très intéressantes ont été mesurées. Cependant, les modèles théoriques n’ont pas permis de calculer des valeurs de contraintes comparables à celles prévues par les simulations et des études complémentaires sont nécessaires.Finalement l’intégration d’YSZ en photonique silicium a été étudiée selon trois approches. La première et la deuxième consistent au dépôt d’YSZ sur des guides d’onde silicium, encapsulés ou non par une couche de silice. La troisième comprend la fabrication de guides d’onde dans une couche d’YSZ, déposée sur un substrat de silicium non structuré. Nous avons mis en évidence l’absence de contrainte dans chacune des configurations, justifiée par la présence de silice à l’interface entre l’YSZ et le silicium. Les pertes de propagation dans de tels guides hybrides YSZ/Si, initialement supérieures à 250 dB/cm ont été réduites à 7,5 dB/cm par l’optimisation de la croissance et de la géométrie des guides. / 21st century stands out as a new numeric area, particularly due to the development of Internet of Things. The exceptional growth of produced, transmitted and stored data all around the world led to new emerging technologies such as silicon photonics. However, silicon has intrinsic limitations for photonic applications including indirect bandgap and centrosymmetry of its lattice.In parallel, functional oxides family exhibits an impressive panel of properties such as ferroelectricity or piezoelectricity. The epitaxial growth is the main limitation for their integration in silicon photonics. Indeed, the lattice mismatch between most of the oxides and silicon induces high defects density which strongly degrades their properties. Nevertheless, one of these oxides, Yttria-Stabilized Zirconia (YSZ), can be used for the lattice transition. The objectives of the PhD work was then to study the YSZ growth mechanisms and to determine its properties in integrated optics.First, the epitaxial growth of YSZ, using Pulsed-Laser Deposition (PLD), as well as the fabrication and characterization of photonics structures have been developed on sapphire substrate. We reported the role of substrate annealing before deposition, on the orientation and quality of YSZ thin film. The optimization of the epitaxial growth, and the development of a fabrication process, allowed the demonstration of YSZ-based waveguides with propagation losses as low as 2 dB/cm. We also characterized more complex passives structures, in particular ring resonators, micro-disks and Bragg filters. Furthermore, third-order optical nonlinear properties in YSZ waveguides were experimentally determined for the first time. The n2 value, obtained experimentally, is in agreement with theoretical calculation and is in the same order of magnitude than the value reported for silicon nitride SiN, a well-known nonlinear material.Due to lattice mismatch and thermal expansion coefficient difference, the growth of YSZ is expected to induce large strain in silicon, breaking its crystal centrosymmetry. Recent experimental and theoretical studies have demonstrated the possibility to exploit second-order optical nonlinear effects in strained silicon, usually vanishing in this material. To probe the strain distribution, seen by an optical mode propagating in a silicon waveguide, we developed an innovative Raman-based experimental technique for integrated optics. Even if typical phonons behaviors have been revealed, theoretical modeling of experimental data did not lead to strain values comparable to the simulation predictions and complementary studies are required.Finally, three approaches have been tested for the integration of YSZ in silicon photonics. The first and second one include the growth of YSZ on silicon waveguides, buried or not in a silica layer. The third one involves the fabrication of waveguides in a YSZ thin film, deposited on a flat silicon substrate. No strains in the silicon have been observed, justified by the silica interfacial layer between YSZ and silicon. Propagation losses of hybrid YSZ/Si waveguides, initially more than 250 dB/cm, have been reduced to 7.5 dB/cm thanks to YSZ growth optimization and an adapted waveguides geometry.
10

跨國無塵室工程公司全球市場競爭研究-以M+W工程公司 為例 / Competitive advantage of global facility engineering company-A case study of M+W

謝昌立 Unknown Date (has links)
在全球激烈的競爭環境下,基於市場規模以及成本考量,海外市場開發儼 然對台灣企業猶如一條不歸之路。因此,本研究針對跨國公司在做全球投資時, 面對全球環境所必須面臨之不確定的狀況,以及在快速變動的環境下,企業如 何掌握並適應整體兢爭環境,擁有競爭優勢,提出探討,祈能對台灣企業有所 助益和借鏡。 以無塵室工程承攬案為例,應對環境周遭的整體競爭環境做仔細的剖析, 才能針對目標市場展開系列的工程承攬活動,發現並把握工程承攬的機會,且 可以避開各種工程承攬的風險與威脅。 另外,卓越的企業應該要調整競爭策略,提昇競爭優勢,不要盲且追求市 場佔有率而更要重視的是如何提供顧客最大的價值。企業最大的挑戰除了是要 創造滿意的顧客,更大的挑戰是要企業所做的每一個決策,所花的每一分錢, 都應該是如何增加忠誠的顧客、並設法留住忠誠的顧客、提高顧客的終身價值, 以及爭取新顧客上門。 除此之外,有效的經營管理、組織學習與策略績效評估,勢將成為企業未 來延續與發展的重心。 關鍵字:Cleanroom 廠務工程 競爭優勢 競爭策略 CAPEX / Under intense global competition environment, and due to cost concerns and global market environment, developing business in global markets is becoming a none return way and surviving strategy of Taiwanese Enterprises. Therefore, this research focuses on an international company involved in global investment while facing uncertain environment, and how the company can quickly adapt to the fast pace of the world market and remaining a competitive edge and advantage. Through this research, I hope to assist companies in Taiwan with some useful advice and reference experience. Taking a clean rooms project as an example we shall analyze carefully the surrounding competitive environment. This helps with any future development of project bidding, and will decrease the risk and threats during various kinds of project bidding. Besides that an elite enterprises should adjust their business strategies to increase their competitiveness so they won’t just blindly follow the market trend, but to provide their customers with the biggest returns. The biggest challenge that enterprises face isn’t just customer satisfaction because every enterprise is capable of making a customer happy. Each decision a company made as well as each dollar that a company spends, should be on how to create a loyal consumer, so that the consumer will keep coming back to increase the final value of each consumer and to attract new consumers. Nevertheless, having efficient business management, knowledge organization and effective strategic evaluation will become the center focus for future developments of all enterprises. Key Words: Clearroom Facility-Engineering Competitive Strategy Competitive-Advantage CAPEX

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