Tesi sul tema "Cave Weta"
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Hansen, Shadeon Doawon. "Economic analysis of water recovery from flue gas: A South African case study". University of the Western Cape, 2020. http://hdl.handle.net/11394/8009.
Testo completoIn order to comply with the Air Quality Act 2010, Eskom will have to install flue gas desulphurisation (FGD) plants for both new and old power stations. Wet-flue gas desulphurisation (wet-FGD) is adopted world-wide as an effective flue gas treatment technology and therefore will be adopted by Eskom. During the process of desulphurisation, the flue gas is stripped of SO2 but gains a substantial amount of water. Sustaining this process requires a continuous supply of fresh water, a scarce resource in many places where power stations are built. This research investigates the economic feasibility of technologies capable of recovering water from flue gas. The following technologies were considered to capture water vapour from flue gas taking Eskom’s Medupi Power Station as a case study; condensing heat exchanger technology, desiccant drying systems and membrane technology using membrane modules developed by other students in this project. The water vapour selective membrane technology turned out to be superior.
De, Wet Margaretha. "Coping, stress and suicide ideation in the South African Police Service in the Northern Cape / Marietha de Wet". Thesis, North-West University, 2003. http://hdl.handle.net/10394/208.
Testo completoThesis (M.A. (Industrial Psychology))--North-West University, Potchefstroom Campus, 2004.
Sinsheimer, Peter. "Fashioning a greener shade of clean integrating pollution prevention into public policy : the case of professional wet cleaning /". Diss., Restricted to subscribing institutions, 2009. http://proquest.umi.com/pqdweb?did=1835200081&sid=1&Fmt=2&clientId=1564&RQT=309&VName=PQD.
Testo completoEkström, Josephine. "Possibilities and obstacles regarding under-five mortality : A case study in Babati district, Tanzania". Thesis, Södertörns högskola, Institutionen för livsvetenskaper, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:sh:diva-17192.
Testo completoTanzania är nära att nå ett av Milleniemålen; att reducera barnadödligheten med två tredjedelar mellan 1990 till 2015. Den här kvalitativa fallstudien fokuserar på barn under fem års hälsosituation i Babati distriktet, beläget i nordvästra Tanzania. De empiriska data som används i studien har samlats genom intervjuer med sjukvårdspersonal och mödrar under tre veckors tid under februari och mars 2012. Syftet med studien har varit att identifiera direkta och indirekta orsaker till barnadödlighet, samt att undersöka vilka förbättringar som krävs för att förbättra situationen. De mest framträdande orsakerna för barnadödlighet är lunginflammation och malaria, men också sjukdomar kopplade till diarré är vanligt förekommande. Förekomsten av sjukdomarna varierar beroende på om det är regnsäsong eller torrperiod. Under regnsäsongen så är det flest sjukdoms- och dödsfall, och lunginflammation och malaria är mest förekommande medans diarré är vanligast under torrperioden. Bakomliggande orsaker som påverkar barnadödlighet i Babati är bristen på infrastruktur, få välfungerande vägar till huvudsjukhusen vilket framför allt påverkar den rurala befolkningen. Den begränsade tillgången till transport är ett vidsträckt problem vid akut sjukdom eller förlossning. Klinikerna i Babati distriktet är undermåligt utrustade och har personalbrist, vilket skapar en ohållbar situation för både sjukvårdspersonalen och patienterna. Mer statliga resurser och infrastruktur behövs i området för att kunna skapa en hållbar situation för framtidens barn.
Miljö och utveckling i syd
Eze, Chuks Paul. "Chemical, physical and morphological changes in weathered coal fly ash : a case study of brine impacted wet ash dump". University of the Western Cape, 2011. http://hdl.handle.net/11394/5420.
Testo completoFly ash is the major waste material produced by power plants in the combustion of coal to generate electricity. The main constituents of fly ash are Si, Al, Fe and Ca with smaller amount of S, Mn, Na, K, and traces of many other elements such as Co, Cd, As, Se, Zn, Mo, Pb, B, Cu and Ni. Fly ash is usually disposed either by dry or wet disposal methods. These disposal methods have raised major environmental concerns due to the potential leaching of chemical species from the ash heap by ingress of rainfall and brine used to transport the fly ash to the dam. This study focuses on the changes in chemical composition, morphology and mineral phases due to weathering, of coal fly ash co-disposed with brine over 20 years at Sasol Secunda ash dump in Mpumalanga Province, South Africa. The design and operation of the Secunda ash dump presupposes that the ash dump may act as a sink for the salts which originated from chemicals used for normal operation in the plants. The majority of these salts come from the brines generated during desalination and raw water regeneration. The aim of this study is to ascertain if the ash dump could serve as a sustainable salt sink.Samples were drawn along the depth of two drilled cores (S1 and S3) from the weathered Secunda ash dump and analysed in conjunction with the fresh (unweathered) Secunda fly ash taken from the fly ash hoppers for comparative analysis. Scanning electron microscopy (SEM), X-ray diffractive (XRD) and X-ray fluorescence (XRF) spectrometry were employed to obtain a detailed morphological, mineralogical and bulk chemical composition of all the samples. Pore water analysis was used to determine the pH, EC and moisture content of fly ash samples. A five step sequential chemical extraction procedure was used to establish the geochemical association of particular elements with various mineral phases. The total acid digestion test was also used to determine the total elemental compositions of the Secunda fly ash samples. The SEM results showed that the fly ashes consist of irregular and numerous spherically shaped particles. Changes (encrustations, etchings and corrosion) in the morphologies of the weathered ash particles were also observed. The XRD results revealed quartz, mullite, lime and calcite as the major mineral phases. Other minerals identified in very minor quantities in the drilled Secunda ash core that were dried prior to analysis were halite, kaolinite, nitratine, bassanite, microline. and hydrophitte. These phases may have formed during sample handling. XRF investigation revealed that the major oxides present in the dumped ash samples were SiO₂, A₂2O₃, CaO, Fe₂O₃, MgO, Na₂O, TiO₂ and the minor elements present were K₂O, P₂O₅, SO₃ and MnO. The sum of the mean values of the % composition of SiO₂, Al₂O₃, and Fe₂O₃ was 70.19 %, and 72.94 % for the two drilled ash core samples (S1 and S3) respectively, and 78.67 % for the fresh ash which shows the significant alteration of the Si, Al and Fe content in the ash matrix over time. The fly ash is classified as Class F using the ASTM C 618 standards. The loss on ignition (LOI) which is an indication of unburned carbon or organic content was 4.78 %, 13.45 % and 8.32 % for the fresh ash, drilled ash cores S1 and S3 respectively. The high LOI values for the drilled ash cores could indicate high hydrocarbon content in the ash dump because of co-disposal practises where hydrocarbon waste are included in the brine stream for disposal on the ash. While the ash samples from the surface appeared dry, moisture content (MC) analysis showed that there is considerable water entrained in the fly ash dump. The fresh ash MC was 1.8 % while core S1 ranged from 41.4 – 73.2 %; core S3 ranged from 21.7 – 76.4 %. The variations in the MC values can be attributed to uneven flow paths due to inconsistent placement conditions or variations in ambient weather conditions during placement. The fresh fly ash (n=3) had a pH of 12.38±0.15, EC value of 4.98±0.03 mS/cm and TDS value of 2.68±0.03 g/L, the pH of the drilled ash core S1 (n=35) was 10.04 ±0.50, the EC value was 1.08±0.14 mS/cm and the TDS value was 0.64 ±0.08 g/L. Core S3 (n=66) had pH of 11.04±0.09; EC was 0.99 ±0.03 and TDS was 0.57 ± 0.01. The changes in pH values can be attributed to the dissolution and flushing out from the dump basic alkaline oxides like CaO and MgO These variations in pH values shows that the fly ash is acidifying over time and metal mobility can be expected under these conditions. The large decrease of EC in the drilled ash cores S1 and S3 compared to the fresh ash indicated a major loss of ionic species over time in the ash dump. The sequential extraction scheme revealed that the elements Al, Si, Ca, Mg, Ba, Sr, Fe, Mn, Na, K, As, Pb, Cr, Mo, Cu, Ni and Zn are present in Secunda fresh and weathered fly ash and are partitioned between the water soluble, exchangeable, carbonate, iron and manganese, and residual fractions of the coal fly ash. It also showed that the trace elements As, Pb, Cr, Mo, Cu, Ni and Zn do not show permanent association with particular mineral phases as a continuous partitioning between different mineral phases was observed in the weathered drilled core. Generally, all the elements had the highest concentration in the residual fraction. But it was evident that the labile phase (water soluble, exchangeable and carbonate fractions) had fairly high concentrations of Si (± 6.5 %), Al (± 6.5 %), Ca (±10 %), Mg (± 5.5 %), Ba (± 7.5 %),Sr (± 7.5 %), Na (± 12 %) and K (± 12 %) for the Secunda drilled ash core (S1 and S3) and fresh fly ash samples. This indicates that these species can leach easily upon water ingress and could pose a danger to the environment. Na and K had the highest concentrations leached out in the labile phase in all the ash samples. The amount of Na leached out of the drilled Secunda ash core in the labile phase was 13.21 % of 18584.26 mg/kg in the five geochemical phases of core S1; and 9.59 % of 11600.17 mg/kg in the five geochemical phases of core S3 while the fresh Secunda fly ash leached out 11.28 % of 16306.30 mg/kg of Na in the five geochemical phases. This study provided significant insight into the pore water chemistry, morphology, mineralogy and chemical composition and the elemental distribution pattern of the major and trace elements in the Secunda fly ash and weathered drilled Secunda ashm core S1 and S3. Though results from XRF analysis and the sequential extraction scheme shows that Na, K, S, Ca and Mg were slightly captured from the co-disposed brine by the Secunda fly ash, these species were however released in the labile phase. Hence there was no significant retention of these species in the ash dump. The amount of these species retained in the weathered ash were (0.26 % and 0.55 %) for Na, (0.02 % and 0.34 %) for K, (0.08 % and 0.06 %) for S, (0.94 % and 0.01 %) for Ca and (0.37 % and 0.96 %) for Mg in drilled ash cores S1 and S3 respectively. This poor retention of Na K, S, Ca and Mg which are major components of Sasol Secunda brine in the drilled ash cores S1 and S3 clearly shows the unsustainability of the Secunda fly ash dump as a salt sink.
Costello, Kelly. "Full Scale Evaluation of Organic Soil Mixing". Scholar Commons, 2016. http://scholarcommons.usf.edu/etd/6076.
Testo completoMehl, Daniel James Gustav. "Assessing the influence of floodplain wetlands on wet and dry season river flows along the Nuwejaars River, Western Cape, South Africa". University of the Western Cape, 2019. http://hdl.handle.net/11394/7031.
Testo completoImproved knowledge is required on the quantity and source of water resources, particularly evident during periods of drought currently being faced in South Africa. There is inadequate knowledge with regards to the flood attenuating properties of wetlands, particularly evident in the ungauged catchments of Southern Africa. This study aims to improve the knowledge on the contribution of flow from tributaries with headwaters in mountainous regions to low lying areas and the effects of wetlands on river flow patterns. Several river flow monitoring sites were established along the major upper tributaries of the Nuwejaars River at which daily water levels were recorded and bi-weekly discharge measurements were conducted. Weather data was collected using four automatic weather stations and three automatic rain gauges’ setup throughout the catchment. Rainfall data coupled with rating curves and daily discharges were used to assess the flow responses of these tributaries to rainfall events. Additionally, stable isotope analysis and basic water quality analysis was used to determine the major sources of flow within the major tributaries. The rainfall and river flow data collected, coupled with the characterization of the wetland was used to determine the flood attenuation capabilities of the wetland. Lastly, a conceptual model based on a basic water balance was developed to further explain the role of the wetland and its effects on river flows. The results showed a 27-hour lag time in peak flows from the upper tributaries at the inflows of the wetland to the outflow. Two of the upper tributaries had flow throughout the year and were fed by springs in the upper mountainous regions of the catchment and all tributaries were largely reliant on rainfall for peak flows. The temporary storage of flows within the wetland occurred as a result of the Nuwejaars River bursting its banks, filling of pools, or ponds and the Voëlvlei Lake. It was concluded that the wetland increased the travel time and decreased the magnitude of flows of the Nuwejaars River. However, due to the fact that wetlands are interlinked on a catchment scale and have a collective effect on flood attenuation this study may be improved by looking at the wetlands within the catchment holistically.
Monagin, Corina Grigorescu. "Case study : how are perceptions of risk in wet markets informing policy implementation of emerging infectious disease control in Guangdong, China". Thesis, London School of Hygiene and Tropical Medicine (University of London), 2013. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.590510.
Testo completoAsseiss, Maraísa da Silva Guerra [UNESP]. "Aplicação do processo de descoberta de conhecimento em banco de dados acadêmico utilizando as tarefas de agrupamento e classificação". Universidade Estadual Paulista (UNESP), 2017. http://hdl.handle.net/11449/151251.
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Nos últimos anos a quantidade de dados armazenados diarimente em empresas e instituições aumentou consideravelmente e um dos motivos que contribuiu para isso é a crescente importân- cia dada à informação. De forma geral, esses dados são meramente armazenados e, portanto, subutilizados pelos seus detentores, enquanto poderiam ser estudados a fim de obter novos co- nhecimentos, informações e relacionamentos. Neste contexto, surge o processo de descoberta de conhecimento em banco de dados. Este trabalho apresenta uma introdução a banco de dados, uma revisão bibliográfica sobre o processo de descoberta de conhecimento em banco de dados, a descrição de cada etapa deste processo, uma explanação sobre as tarefas de agrupamento e classificação, além de resumir brevemente as técnicas de particionamento e árvore de decisão. É exposto um estudo sobre o sistema Weka, em que apresenta-se conceitos, funcionalidades e exemplifica-se diversas formas de utilização do sistema. O objetivo principal deste trabalho é propor uma metodologia para descoberta de novos conhecimentos em bancos de dados acadê- micos baseada no processo de descoberta de conhecimento em banco de dados, sendo esta uma metodologia mais simplificada e de execução mais direcionada. Como parte da metodologia este trabalho contribui ainda com uma aplicação desenvolvida em Python como forma de apoio a etapas da metodologia. A metodologia proposta conta com a ferramenta Weka para execução dos algoritmos de data mining e prevê a execução das tarefas de agrupamento e classifica- ção. Por fim o trabalho retrata dois estudos de caso envolvendo bancos de dados acadêmicos reais e a execução de todas as etapas da metodologia proposta, com a utilização do sistema Weka. Os estudos de caso abordam as tarefas de agrupamento e classificação e as técnicas de particionamento e árvores de decisão, com a utilização dos algoritmos SimpleKMeans e J4.8, respectivamente. Os resultados obtidos através dos estudos mostram que a metodologia pro- posta é capaz de gerar conhecimentos novos e úteis, tanto na análise de dados de desempenho acadêmico quanto na análise de dados socioeconômicos dos alunos.
In the past years the amount of data stored daily in companies increased considerably and one of the reasons that contributed to this fact is the increasing importance given to information. In general these data are merely stored and therefore underused by its owners, while they could be studied in order to find out new knowledge, information and relationship. In this context, the knowledge discovery in database process arises. This work presents an introduction to databa- ses, a bibliographic review about the knowledge discovery in databases process, a description of each step of this process, an explanation about the clustering and classification tasks and the summarization os the partition and decision tree techniques. A study of the Weka system is shown, in wich are presented concepts, functionalities and examples of use forms for the sys- tem. The main objective of this work is the proposal of a methodology for knowledge discovery in academic databases based on the KDD process. The presented methodology is a more sim- plified and directed version of the KDD. As part of the methodology this work also presents an application developed in Python programming language as a support tool for the methodology steps. The presented methodology uses the Weka tool for running the data mining algorithms and considers the clustering and classification tasks. Lastly this work describes two case stu- dies involving real academic databases and the execution of all the steps from the proposted methodology using the Weka system. The case studies addresses the clustering and classifica- tion tasks, as well as the partitioning and decision trees techniques, using the SimpleKMeans and J4.8 algorithms respectively. The obtained results show that the methodology is capable of generating new and useful knowledge, both by analyzing academic performance data and by analyzing students’ socioeconomic data.
Schellhorn, Matthias. "Rural tourism in the 'Third World' : the dialectic of development : the case of Desa Senaru at Gunung Rinjani National Park in Lombok Island". Phd thesis, Lincoln University. Environment, Society and Design Division, 2007. http://theses.lincoln.ac.nz/public/adt-NZLIU20080221.124834/.
Testo completoBerg, Martin, e Albin Eriksson. "Toward predictive maintenance in surface treatment processes : A DMAIC case study at Seco Tools". Thesis, Luleå tekniska universitet, Institutionen för ekonomi, teknik, konst och samhälle, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-84923.
Testo completoMiller, Benjamin Verlinden. "The Hydrology of the Carroll Cave-Toronto Springs System: Identifying and Examining Source Mixing through Dye Tracing, Geochemical Monitoring, Seepage Runs, and Statistical Methods". TopSCHOLAR®, 2010. http://digitalcommons.wku.edu/theses/216.
Testo completoJohnson, Erin Johnson. ""Strong Passions of the Mind": Representations of Emotions and Women's Reproductive Bodies in Seventeenth-Century England". Miami University / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=miami1531759449299599.
Testo completoTsai, Yen-Cheng, e 蔡炎成. "Semiconductor Process Tools ─Case for Wet Station". Thesis, 2018. http://ndltd.ncl.edu.tw/handle/bjzucp.
Testo completo淡江大學
化學工程與材料工程學系碩士班
106
This technical report is about the project plan of a Wet Station during the period of intern of Ding Cheng International Co., Ltd. The work in the project is to assist in the collection of related information such as hardware equipment, electrical control and software of this Wet Station, and to write a manual for the operation of the Wet Station. The equipment improving is based on the combination of two different system models. In terms of hardware, the piping of each acid bath unit is redesigned, and other equipment-related parts are replaced. The addition of equipment components to the machine is a functional design of the protection mechanism such as sensors, quick drain pump, and fast refill water valves in the acid bath unit. In order to replace the bath plate, the chemical resistance of the plate was tested. In terms of software, the software technology part of the computer control is very difficult to rewrite. In addition to integrating the control instructions of the machine, it also redesigned the control interface of the operating system and increased the Chemical Mode Select system''s function of rapid acid exchange. These are convenient and quick control process steps for the operator. About the chemical resistance test of new and old plates is based on considerations of material replacement for the acid bath unit and plate suppliers. Experimental plates were placed in an acidic environment and closed system conditions, and the plates were observed for changes in surface and weight after controlling for different experimental times. The experimental results showed that the old and new plate surface appear the phenomenon of aging and the color was darkened. However, there were no signs of destructive corrosion, embrittlement, or cracking on the surface, and there is no obvious difference in weight change. The results of this experiment can provide a reference for customers and vendors as replacement plates.
WU, CHE-YU, e 吳哲宇. "A Case Study on Critical Events of A-Wea". Thesis, 2018. http://ndltd.ncl.edu.tw/handle/27h245.
Testo completo國立雲林科技大學
企業管理系
106
ABSTRACT This study uses in-depth interviews and secondary data, targeting Taiwan listed company A-Wea. According to the research and suggestions of past scholars, analyzing of the equity structure design, role of venture capital, listed on the stock exchange before VC sells equity in the early stage of A-Wea company. And use organizational change steps to discuss for president encountered a large number of employees leaving the company. The result of this study as follow: 1. In the early stage of startup, the proper equity structure design was not done. It would easily lead to the replacement of the operating rights of the major shareholder or management team in the company. 2. In the case of start-up managers who lack resources and use equity for the growth of the company and the future value of the company, the company will easily lose control of the company after it grows. 3. In the Taiwan legal regulations, if manager want to have the managerial authority in the company, you must raise your holdings to 33%. 4. Before VC sells their equity, manager must do financial planning and holding 33% of the shares or more than half of the seats on the board of directors, as opposed to selling the shares to the market, the friends and relatives which can reduce the risk of the company's control and continue to operate the company. 5. For the operators, after a large number of employees leave the company, they can be used as an opportunity for organizational reconstruction, and properly manage the changes and development that will help the future growth of the company. Keyword: Equity design, Venture Capital, A large number of employee leave
Kao, Chun-Hsien, e 高群賢. "Safety Assessment of Second-Hand Semiconductor Process Tools ─Case Study for Wet Bench". Thesis, 2010. http://ndltd.ncl.edu.tw/handle/35616845990259883485.
Testo completo國立交通大學
工學院碩士在職專班產業安全與防災組
99
As manufacturing technology advances, investment in the construction of wafer FAB is large. In the past, to build an 8” FAB requires NTD 30 billion yuan, and now to build a 12” FAB requires at least NTD 100 billion yuan. Among the investment in the semiconductor industry, the expenditure for the purchase of machine equipment is the highest, accounting for about 60% to 70%. As purchasing second-hand equipment can reduce costs for factory Construction and depreciating machines, competitive advantage can be enhanced. However, it is difficult for the buyers to control the durability and safety of second-hand equipment, particularly the material of the wet bench in the past is mostly polypropylene (PP) or polyvinyl chloride (PVC). They are all flammable, and when burnt, high heat and large amount of smoke will be produced. Moreover, there are heating devices and flammable chemicals inside the machine, so it’s very easy to catch fire in the past, and the loss is also very serious. Therefore the wet bench areas are regarded as the focus of fire protection by all factories. This study takes a model of wet bench equipment in the 8” FAB as the object for assessment, discussing risks in safety and fire of running many-year-old machines through the risks in the machines’ internal tank, electrical units, chemical supply, as well as the material hardware, safety protection and interlocking devices.
Tsai, Charng-Jin, e 蔡長晉. "Exploring Factors of Constructing Effective Communication for a Project Technical Team:The Case of Wet Process Sector". Thesis, 2013. http://ndltd.ncl.edu.tw/handle/42x5ye.
Testo completo開南大學
商學院碩士在職專班
102
As a result of dense industrial clusters in Taiwan’s wet process sector there is a need to shorten the distance of communication and also make more possibilities for communication. In order to construct effective communication for a project’s technical team it is first necessary to explore the factors involved. After literature reviews and expert interviews, this study constructs three dimensions and 15 criteria for the purpose of evaluating effective communication for a project technical team. A survey elicited the opinions of 30 experts in the wet process sector by questionnaire. The fuzzy linguistic preference relation (Fuzzy LinPreRa) approach is employed to assess the importance of these evaluation criteria. The goal is to help the project technical team pay attention to matters involved in the process of constructing effective communication. The results of the survey indicate that in order to construct effective communication for communication conduct for a project technical team, we should focus on crisis management; in particular, when a crisis occurs, it is necessary to manage it prudently when making statements to specific persons or indefinite ones; in order to reach the communication objective, we need to clarify communication purposes carefully and confirm the target before communicating; communication frequency is another important point, the appropriate frequency of communicating will promote information renewal, and ensure the information on both sides was identical. This study suggests that we should apply Agile Project Management to assist in executing the project. When executing the project, we should not focus on only one kind of project management methods, but instead we should apply Agile Project Management and Traditional Project Management depending on the case so as to achieve the goal of the project.
Chen, Mao-Kun, e 陳楙昆. "Risk Assessment of the Fire Security Surveillance System on Wet Bench Case Study for a Semiconductor Factory". Thesis, 2013. http://ndltd.ncl.edu.tw/handle/d44xrz.
Testo completo國立交通大學
工學院產業安全與防災學程
102
In semiconductor processes, the wet bench uses the most organic solvents. During the process, the wafer is dried by heating at high temperature until evaporation occurs which leads to the potential risk of fire and explosion. Among all organic solvents, isopropyl alcohol has the lowest minimum ignition energy of 0.65 mJ, which is so low that even a spark of static electricity could ignite it leading to fire and explosion hazard. Numerous records and documents have pointed out the potential risk of company property and personnel safety if the safety device of the relevant production line is inadequate. When using the flammable organic solvent bench, fire extinguishing equipment is necessary because of the potential fire hazard. With the advances of semiconductor processes and the improvement of equipments, potential risks also evolve. The accompanied improvement and upgrade of the extinguishing system to an intelligent safety surveillance system includes such functions as graphical control, a back-up assistance system and responsible management organization etc. Although these functions decrease the probability of risks, the issues of incompetent technicians, unfamiliar operation and the troubleshooting of the equipment still require improvement. This research focuses on the safety surveillance system of the wet bench in a semiconductor factory and studies its failure module and FMEA (Failure Modes and Effects Analysis). The failure frequency of the equipment components and human negligence are discussed in order to control the encountered disaster or malfunction effectively and reduce the frequency of fire hazard and production interruption in the wet bench. It is hoped this will help the sustainable operation of the company.
Chou, Hsiu-Chien, e 周秀堅. "Effect of pre-gelatinization of diffferent moisture ratio wet milling rice paste on the quality of rice cake". Thesis, 2004. http://ndltd.ncl.edu.tw/handle/08860483918824773471.
Testo completo國立中興大學
食品科學系
92
Abstract Rice cake , such as salt rice cake、radish rice cake、rice cup cake , are popular Chinese-style rice processed food. Mainly the raw material is Indica rice utilizing gelatinizing characteristic of rice pastes , and then we can get rice production with good-looking appearance and fine texture. In the experiment , the nation TNuS19 rice was adopted as the raw material. The researcher focused on effect of the pre-gelatinization of wet milling rice paste under the conditon of different ratio of rice and water as 1:2,1:3, and 1:4. The analyzed items included chemical composition of rice , rapid viscosity analyze(RVA), rice paste particle size , scanning electron micrographs(SEM), normal and polarized light photomicrographs , colorness , moisture content , texture , hollowness , sensory evaluation. The experimental results showed below:the rice kernel adopted as the raw material absorbed equivalently(0.17g water/ g rice) after being steeped for 40 minutes. After dried by the centrifuge dehumidifier , the rice flours were tested moisture and showed the moisture 43%~44% or so . The Rapid Visco Analyze(RVA) showed dry milled rice flours have lower viscosity than frozen rice paste ; the morphological structure photographed by Scanning electron microscopy of rice kernel granule with dry milled has lower completeness. The physical properties and texture experiments , rice paste pre-gelatinization process、moisture content affect the hollowness、springiness and chewiness of the products. The rice and water ratio 1:2 was more harder , but 1:4 was softer. Microstructures of 1:2,1:3,1:4 we observed photographed by SEM are from compactness to sponginess. The result of sensory evaluation showed that rice and water ratio 1:3 is more popular among the evaluators. In conclusion , after rice steeping for 40 minutes , wet-milled rice paste with 1:3 , set gelatization time 180 seconds , finally in the process of steaming , following procedure above we can get better products. In addition , rice cake produced from wet-milled rice paste have better quality in texture than that produced from air-hot dry rice flours.
Fang, Chi Pin, e 方啓賓. "Cost-benefit Analysis on Tool Exchange in The Wet Processes - A Case Study of A Semiconductor Manufacturing Company". Thesis, 2016. http://ndltd.ncl.edu.tw/handle/u72p38.
Testo completo長庚大學
商管專業學院碩士學位學程在職專班經營管理組
104
For any semiconductor company facing process conversion, purchasing too much machinery may result in waste and cause clean room space idle; but if too little purchased, then insufficient capacity can lead to the risk of product shortage. Hence, it has been an important issue for semiconductor companies to decide the “optimal” number of fab machines. By taking a semiconductor company as an example, this thesis carries out the cost-benefit analysis on the machine conversion problem of wet processes. This study considers the case of two different wet-chemical washing machines (DHF and SPM), and builds a mathematical programming model to find the benefit-maximizing number of machines procured and channel number of conversion process, subject to the constraints on capacity requirements, yield level and conversion standards. Research results include (a) the number of DHF machines is more sensitive to the cost-benefit analysis; (b) when the marginal yield rate of SPM machines is less than 0.02%, the conversion to SPM group contributes nothing to the problem; and finally (c) benefit of machine conversion naturally decreases as the unit price of single SPM machine increases, and no good to add any SPM machine when it costs more than NT$ 195 million. Conclusions of this thesis on how the number of channels in the wet process, yield and the unit price affect the benefit in machine conversion problem may provide a guideline to the semiconductor industry in making machinery investment decision.
Li, Chen You, e 陳宥莉. "Analysis of Management and Growth Strategy in Taiwan Wet Electronic Chemical Industry-A case study of P Company". Thesis, 2019. http://ndltd.ncl.edu.tw/handle/g83a8q.
Testo completo國立臺灣大學
事業經營碩士在職學位學程
107
In 2017, the total market value of Taiwan''s semiconductor industry supply chain was reached to NT$2.46, which ranking is No.3 of the world, and it took the lead in the foundry and semiconductor manufacturing field. How Taiwan can have a unique market position in this industry, the complete supply chain inside Taiwan shows a significant meaning. In addition to leading technical competitiveness comparing with South Korea, United States, and Japan, Taiwan Semiconductor''s complete upstream supply chain not only allows customers to produce continuously, but also supplies high-quality, low-cost wet chemicals to semiconductor customer, which empower the industry to have low cost and efficient in manufacturing. In the paper, the electronic wet chemical industry selected the leading P company to conduct a case study to analyze its origins from the company''s founding, strategy selection from target concentration, cost leadership, to the current evolution to differentiation strategy, and to be internationally. Understanding P company’s establishment to expand market share and gradually develop a multi-product portfolio can be used as a reference for the development planning of one company''s growth and resource allocation.
Wang, Hsinng-Pin, e 王祥斌. "Investigation of Preservatives and Microbe Levels in Commercial Wet Rice Products (Rice Flour, Turnip Cake, Steamed Rice Cake in Bowl, Mitaibah, Flat Rice Noodle) Sold in Taipei Markets". Thesis, 2012. http://ndltd.ncl.edu.tw/handle/27877405484941454001.
Testo completo李世偉. "A Simulation Study of Suitable Processing Factors for Batch-Process Workstations with Multiple Attributes - A Case Study of Furnace and Wet Bench Operations". Thesis, 2007. http://ndltd.ncl.edu.tw/handle/01610755440474229897.
Testo completo國立清華大學
工業工程與工程管理學系
95
Semiconductor wafer fabrication facilities face a variety of challenges. The combination of shrinking device geometries and increasing interconnect levels is rapidly increasing process complexity. It is leading to higher manufacturing costs and longer cycle times. Cycle time is one of the most important issues in semiconductor industry. In wafer fabrication processes, batch process steps account for approximately 25%~ 30% of the overall cycle time. This is caused by the long process times, batch sizes, hot lots and the batching rule of the batch process. These batch processes machines such as furnace and wet bench has major impact on the total cycle time. Comparing to batch process machines, single wafer process (SWP) machines enable shorter cycle time to promote faster product development, quicker ramp up of new products and earlier yield correction leading to economic benefits. However, the cost/benefit tradeoff is the major concern for a Fab to replace batch process machines with single wafer process machines. This study uses discrete-event simulation and Taguchi methods to investigate optimal process factors (i.e. hot lot ratio, batching rule, time constraint, and etc) of batch process in furnace and wet bench areas. Results of simulation proved the batch process in furnace area and hot lot ratio have major impact on cycle time. This study attempts to find an optimal combination of batch process and single wafer process machines in furnace area. And given the same cost, an optimal combination of batch process and SWP machines can be found to reduce normal lot cycle time by 4.0~4.5% and hot lot cycle time by 6.1%~16.4%, and increase batch process capacity efficiency by 15.3%~~23.4%. The result of the study provides managers insights for the cost-effect of single wafer process machines. And the methodologies proposed can be used by practitioners to support the decision making for adopting single-wafer process machines.
Yeh, Shu-hung, e 葉書宏. "Semiconductor Assembly Manufacturing Industry Control of Volatile Organic Compounds by Wet Scrubbing and Advanced Oxidation Technology--Case Feasibility Studies of Full-Scale Plant--". Thesis, 2010. http://ndltd.ncl.edu.tw/handle/67700774020785291383.
Testo completo國立中山大學
海洋環境及工程學系研究所
98
Taiwan semiconductor manufacturing industry ranks top in the world for the production and has a great contribution to Taiwan economics. However, the industry produces a significant amount of volatile organic compounds (VOC) into the air. According to EPA of Taiwan, the annual VOC emission amounts from the industry were approximately five thousand tons, a major stationary source of VOC emission. The EPA has implemented the air pollution control regulation for semiconductor industry, in which the VOC emission amount should be below <0.6 kg/hr or the removal efficiency should be >90% for each factory . The conventional control technologies for the VOC emissions was concentration using zeolite followed by thermal oxidation. However, the high boiling points of VOC is difficult to desorbed from zeolite and it required the water to wash the zeolite. This would reduce the removal efficiency of zeolite. This control processes have high operation cost and may produce byproducts required for further treatment. Advanced chemical oxidation process (AOP) recently has gained tremendous attention as an emerging control technology of VOC due to low treatment cost and few oxidation byproducts. The major oxidant of the technology is believed to be hydroxyl radicals, which can react organic compounds at very reaction rates. A majority of VOC emissions from the semiconductor industry are highly soluble and can be easily dissolved into water by scrubbing process. However, the wet scrubbing process can produce a significant amount of wastewater. The objective of this study was to investigate the feasibility of using wet scrubber and O3/H2O2/catalyst process on controlling the VOC emissions from the semiconductor manufacturing industry. A full scale of process of 1000 CMM flowrate was designed and built along with a semiconductor packaging facility. Results showed that major compounds of the VOC exhaust were iso-propanol, PGMEA, PGME and methyl ethyl keton. The inlet concentrations of THC significantly varied from 50 to 600 ppmv as methane. The AOP process can removed 90-95% of VOCs and the scrubbing water can be recycled and reused at least 95%. The capital cost of the system was NT20,000,000 with the annual operation cost of NT120,000 which was only 36-40% of it for the concentration using zeolite followed by thermal oxidation.
WANG, MIN-WEI, e 王敏為. "A Study of the Impact of Cadmium Bromide Collodion Substitutes on Wet Plate Photographic Tone--The Case of Quinn Jacobson New Guy Formula". Thesis, 2017. http://ndltd.ncl.edu.tw/handle/e23su5.
Testo completo世新大學
圖文傳播暨數位出版學研究所(含碩專班)
106
Most of the preparations used for wet production of ferric chloride or cadmium iodide, today, environmental awareness, we try to use cadmium bromide as a control group of Quinn Jacobson new iron ore iron ore formula, with potassium bromide, sodium bromide , Ammonium bromide and Lithium bromide instead of cadmium bromide, adjust the torch formula, the actual shooting and measurement images in the gray guide table, compare the experimental group salt tone tone performance. Potassium bromide potassium iodide formula performance even more than the formula cadmium bromide is good, but its storage is poor, without the need for long-term storage under the premise that the wet board craft enthusiasts can adjust the use of fresh potassium bromide potassium iodide salt stained collodion to replace the environment and the human body harmful cadmium bromide micelle body.
CHIU, YU-LING, e 邱鈺玲. "The Feasibility Study of Wet Scrubber with Micro/Nano Bubbles to Improve the Efficiency of MEK Absorption-A Case Study of Copper Clad Lamainate". Thesis, 2018. http://ndltd.ncl.edu.tw/handle/35zcq6.
Testo completo國立中山大學
環境工程研究所
106
In this study, the application of micro/nano bubbles wet scrubber to process methyl ethyl ketone in the exhaust process of flexible copper clad lamainate was investigated. This was done in order to evaluate the removal efficiency of VOCs-MEK in the exhaust emissions from the process of processing the flexible copper clad lamainate scrubber in the micro/nano bubbles wet scrubber. The adjustment of parameters as well as the evaluation of scrubber processing VOCs-MEK efficiency, along with the understanding of the practicality of the plant, would help to increase the application of technology development, improve processing efficiency, so as to reduce the emission of volatile organic compounds in the air. The removal efficiency in micro/nano bubbles water circulation shows that with the increase of treatment time, the removal rate decreases, and the COD in the washing liquid increases, thus the removal rate cannot be sustained. In micro/nano bubbles water without recycling conditions, there is an 80% removal rate at the beginning, but the overall trend of removal efficiency still decreases, yet the removal efficiency can be maintained at more than 40%; the conductivity and removal rate have no obvious change and the pH in water the COD will increase with time. The ORP test value change will increase as the removal rate decreases. It will no longer rise to a flat level after rising to a constant value; and each parameter shows that VOCs-MEK can be increased through the adjustment of the operating parameter - intake air flow rate and removal rate. Comprehensive test results show that the non-recycling test can increase the removal rate of VOCs-MEK-containing off-gas in the micro/nano bubbles wet scrubber and maintain it at about 40 to 80%; increasing the air volume can increase the removal efficiency of this set of equipment by 7%.
Fourie, Charmaine. "'n Opleidingsprogram vir voornemende pleegouers (Afrikaans)". Thesis, 2008. http://hdl.handle.net/2263/27100.
Testo completoThesis (DPhil)--University of Pretoria, 2008.
Social Work and Criminology
unrestricted
Bottaro, Lucas Eduardo Vieira. "Assessment of the displacements and deformation mechanisms in a rockfill dam. Case study of Cerro da Mina Reservoir". Master's thesis, 2021. http://hdl.handle.net/10316/94302.
Testo completoReservatório Cerro da Mina é um reservatório de águas industriais, parte do complexo mineiro de Neves-Corvo, ao sul de Portugal. Impermeabilizado a montante por uma membrana de PEAD e construído aproximadamente metade em enrocamento e metade em rocha escavada, esta barragem esteve sujeita a três momentos de assentamento abruptos no aterro nos seus primeiros anos de operação. Este comportamento levantou questões acerca da natureza dos movimentos e da possibilidade de algum problema inesperado. A análise dos dados de nove extensómetros e de um inclinómetro instalados na secção de maior altura do enrocamento, juntamente com a avaliação das condições ambientais nos períodos em causa, revelaram que os deslocamentos significativos e inesperados coincidiram com períodos de intensa pluviosidade e subida no nível de água no reservatório. Tanto as deformações verticais como as horizontais apresentaram tendência de aumento acelerado sempre que um novo máximo no histórico de precipitações era registrado. O comportamento observado sugere que o aumento da humidade nos vazios do enrocamento gera uma redução significativa nos valores de sucção nos poros dos elementos rochosos, causando colapsos induzidos por molhagem no enrocamento. Além disso, os dados de observação indicam uma reduzida influência da oscilação do nível de água no reservatório na direção vertical, descartando este fator como causa principal dos assentamentos no enrocamento. As taxas de deformações verticais a longo prazo foram calculadas e apresentaram tendência similar ao previsto para este tipo de estrutura, não demonstrando sinais de problema neste sentido.
Reservatório Cerro da Mina is an industrial water reservoir part of Neves-Corvo mining compound, in the south of Portugal. Covered by an upstream impervious HDPE membrane and constructed approximately half on rockfill embankment and half on excavated rock, this dam experienced three moments of abrupt settlements on its embankments in the first years of operation. This behaviour raised concerns regarding the nature of the movements and the possibility of unanticipated problems. The analysis of the data from nine extensometers and one inclinometer installed in the highest section of the rockfill embankment, along with the assessment of the environmental conditions in the periods of interest, revealed that these significant unexpected vertical displacements coincided with periods of intense rainfall and rise in the water level in the reservoir. Both vertical and horizontal deformations of the rockfill showed a tendency of sudden increase when a new maximum in the precipitation record occurred. This represents an indication that the increase in humidity in the rockfill voids led to a significant decrease in the rock pore suction, causing wet-induced collapses in the rockfill. Additionally, the influence of the oscillation of the water level reservoir was estimated very small in the vertical direction, rejecting this factor as a major source of settlements in the rockfill. Long-term vertical deformation rates in the rockfill were calculated and presented a tendency fairly similar to what is expected for the kind of construction, showing no evidences of problems in that matter.