• Title/Summary/Keyword: IPA.

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Fabrication of Silicon Micromenbranes for MEMS Applications (MEMS용 실리콘 마이크로 멤브레인의 제작)

  • Chung, Gwiy-Sang;Park, Chin-Sung
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2000.05b
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    • pp.7-12
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    • 2000
  • This paper presents the electrochemical etch-stop characteristics of single-crystal silicon in a tetramethyl ammonium hydroxide(TMAH):isopropyl alcohol(IPA):pyrazine solution. Addition of pyrazine to a TMAH:IPA etchant increases the etch-rate of (100) silicon, thus the elapsed time for etch-stop was shortened. The current-voltage (I-V) characteristics of n- and p-type silicon in a TMAH:IPA:pyrazine solution were obtained, respectively. Open circuit potential(OCP) and passivation potential(PP) of n- and p-type silicon, respectively, were obtained and applied potential was selected between n- and p-type silicon PP. The electrochemical etch-stop is applied to the fabrication of 801 microdiaphragms having $20{\mu}m$ thickness on a 5-inch silicon wafer. The averge thicknesses of 801 microdiaphragms fabricated on the one wafer were $20.03{\mu}m$ and standard deviation was ${\pm}0.26{\mu}m$. The silicon surface of the etch-stopped microdiaphragm was extremely flat without noticeable taper or other nonuniformities. The benefits of the electrochemical etch-stop in a TMAH:IPA:pyrazine solution become apparent when reproducibility in the microdiaphragm thickness for mass production is considered. These results indicate that the electrochemical etch-stop in a TMAH:IPA:pyrazine solution provides a powerful and versatile alternative process for fabricating high-yield silicon microdiaphragms.

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IPA Analysis on the Users' attribute of National Recreation Forest Service Program - Forest Environmental Education and Culture Program - (국유자연휴양림의 서비스 프로그램에 대한 IPA분석 -산림환경교육과 산림문화프로그램을 대상으로-)

  • Kim, Bum-Soo
    • Journal of Environmental Science International
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    • v.20 no.6
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    • pp.721-728
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    • 2011
  • This study investigates the users' perception of the importance and performance of National Recreation Forest Service Programs quality, forest environmental education and cultural benefits, with the aim of improving the level of service quality within the programs. An Important-Performance Analysis (IPA) was performed to determine significant patterns. The IPA results showed that most users' perceived as important how well the service programs performed to meet their expectations. The enclosed study finds, for example, users' answered that three factors which were less important to them were entrance fee, size of program center or facilities and amount of information. These factors performed poorly, and the program of guidance indicates the need for improvement of these factors. In addition, the finding also suggests how recreational service programs in the future can complement and improve what they offer. These are as follows. The process of preparation and content of the program order need to be effectively established. The Program Director needs to maintain a friendly attitude and must have ongoing training on how to provide effective programs. For programs to be enjoyable and satisfying for users, the location of the programs should provide a comfortable environment. Also, detailed program guidance is required for users' convenience. It is expected that the results of this study will be useful when ameliorating and establishing the marketing strategy of the National Recreation Forest Service Programs.

The IPA of Multilateral Perception on Foodservice Quality of Hospital Funeral Centers : Focusing on Foodservice Operators, Chief mourners/the bereave and Funeral Visitors (의료기관 장례식장 급식품질의 다자간 인식차이 및 IPA 분석: 장례식장 급식운영 담당자, 상주 및 유족, 조문객을 중심으로)

  • Park, Moon-Kyung;Lee, Jung-Yoon;Jeong, Yun-Hui
    • Korean journal of food and cookery science
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    • v.30 no.2
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    • pp.228-238
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    • 2014
  • This study identified the importance and performance perceptions of funeral foodservice service quality toward funeral foodservice employees, chief mourners/the bereaved and funeral visitors. Data were collected using self-administered questionnaires from 102 funeral foodservice employees, 71 chief mourners/the bereaved and 293 funeral visitors. According to the result of the survey, 'hygienic food production process' was recognized as the most important attribute while 'neat appearance of food' had the least performance. By comparing the importance of service quality attributes between three subject groups, it can be identified funeral foodservice employees had the highest recognition while funeral visitors had the lowest (p<0.001). Furthermore, funeral foodservice employees had a significantly high performance level compared to chief mourners/the bereaved in all 19 service quality attributes (p<0.001). The IPA result toward funeral foodservice employees indicated the following attributes that required improvements: 'reasonable menu price' and 'kindness of helpers'. Another IPA result from chief mourners/the bereaved recognized 'reasonable menu price' as a service priority. Overall, implications for funeral foodservice managers regarding service quality improvement are discussed.

A Study on the Comparing the Structure of Bulks with Thin Films of Amorphous Ta-IPA using XRD (X-선 회절을 이용한 비정질 Ta-IPA 괴상과 박막의 구조 비교에 관한 연구)

  • Yoon, Dai-Hyun;Kim, Hwa-Min
    • Journal of the Korean Chemical Society
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    • v.35 no.6
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    • pp.653-658
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    • 1991
  • The structural variation process and relation of water of amorphous Ta-IPA bulk and thin film upon heat-treatment conditions of $25^{\circ}C$ and $340^{\circ}C$ have been studied by using the radial distribution functions$ (RDF_{obs})$ estimated from the X-ray diffraction intensities, TG-DTA and Infrared spectrophotometer. The expected Ta-IPA structure was determined by comparing the $ RDF_{obs}$ with that for $RDF_{calc}$. The structure of specimens prepared by sol-gel method is basically based on the L-$Ta_2O_5$ crystal. Thin film of samples are mainly composed of octahedral Ta$O_6$and have smaller cluster than bulk samples.

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The Effect of Pyrazine on TMAH:IPA Single-crystal Silicon Anisotropic Etching Properties

  • Gwiy-Sang Chung;Tae-Song Kim
    • Transactions on Electrical and Electronic Materials
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    • v.2 no.2
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    • pp.21-25
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    • 2001
  • This paper presents the effect of pyrazine on tetramethylammonium hydroxide (TMAH):isopropyl alcohol (IPA) single-crystal silicon anisotropic etching properties. With the addition of IPA to TMAH solutions, etching characteristics are exhibited an improvement in flatness on the etching front and a reduction in undercutting, but the etch rate on (100) silicon is decreased. The (100) silicon etch rate is improved by the addition of pyrazine. An etch rate on (100) silicon of 0.8 ${\mu}{\textrm}{m}$/min, which is faster by 13% than a 20 wt.% solution of pure TMAH, is obtained using 20 wt.% TMAH: 0.5 g/100 ml pyrazine solutions, but the etch rate on (100) silicon is decreased when more pyrazine is added. With the addition of pyrazine to a 25 wt.% TMAH solution, variations in flatness on the etching front are not observed and the undercutting ratio is reduced by 30~50%. These results indicate that anisotropic etching technology using TMAH:IPA:pyrazine solutions provides a powerful and versatile method for realizing of microelectromechanical systems.

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A Study on the Degradation of Isopropyl Alcohol with $TiO_2$-coated Metal (광촉매 코팅 금속의 IPA 분해 특성 연구)

  • Yu Dong-Sik;Park Jae-Hyeon;Ha Jin-Wook
    • Proceedings of the KAIS Fall Conference
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    • 2005.05a
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    • pp.279-282
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    • 2005
  • 본 연구에서 광촉매 $TiO_2$/P-25를 알루미늄 금속판에 코팅하여 코팅 조건에 따른 IPA 분해 활성을 고찰한 결과, 무기계 바인더인 KR-400, 유$\cdot$무기복합 바인더인 TMOS, 유기계 바인더인 A-9540을 사용하여 코팅한 알루미늄 금속판의 표면상은 모두 깨끗하였다. 부착력은 무기계 바인더를 제외한 바인더에서 우수한 것으로 나왔다. 또한 IPA 분해 효율은 무기계 바인더 < 유$\cdot$무기 복합 바인더 < 유기계 바인더 순으로 나타났다. 유$\cdot$무기복합 바인더와 P-25의 비율을 10: 10, 8.3: 10, 6.6: 10, 5: 10, 3.3: 10, 1.6: 10으로 바꾸어 광분해 실험을 수행한 결과, 1.6:10일 때 IPA 분해 효율이 가장 우수하였다. 상용화된 타사(A사, B사) 제품과의 성능 비교 결과, 본 연구에서 사용한 바인더(A-9540): P-25의 비율을 1: 6으로 배합하여 코팅 한 알루미늄 판의 IPA분해 효율이 가장 우수하였다.

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Study on Choice Attributes for Low-Cost Carriers Using IPA (저가항공사 선택속성 IPA분석 연구)

  • Park, Young Sik
    • Journal of the Korean Society for Aviation and Aeronautics
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    • v.21 no.4
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    • pp.112-118
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    • 2013
  • Air travel demand has recently been growing and establishment and operation of low-cost carriers have been increased. Against this backdrop, low-cost carriers need to figure out diversified customer demand for low-cost carriers and ways to maximize marketing efficiency before applying it to the field so that they can attain superiority to large carriers in increased intensified competition. Low-cost carriers need to be differentiated from other carriers for the purpose of improving profits. Toward this end, this study conducted analysis on importance and satisfaction with carrier choice using IPA with regard to low-cost carrier customers. In conclusion, the paper accurately examined advantages and disadvantages of low-cost carriers compared to general carriers based on results of IPA analysis and suggested managerial strategies to enhance competitiveness based on division into four parts including maintenance and enforcement (1st quadrant, Delay compensation, Booking rapidity, Check rapidity, Crew service, refund service, baggage service, punctuality, transit services, airlines images), concentrated improvement (2nd quadrant, price, Convenience of seat), passive administration (3rd quadrant, Boarding service, cabin cleanliness, flight schedule, whether local crew on board, meal service, in-flight entertainment service), and enhanced satisfaction (4th quadrant, duty-free service, Variety of routes), so that practical suggestions could be presented to employees working in the field.

Identification of Quality Attributes of University Foodservice and Factors Required for the Improvement of Customer Satisfaction: A Case Study Using IPA Model (대학급식 서비스 품질 속성 및 품질 개선요인 도출: IPA 모델 적용 사례연구)

  • Lee, So-Jung;Jung, Hyun-Young
    • Journal of the Korean Dietetic Association
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    • v.16 no.3
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    • pp.208-225
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    • 2010
  • Our research consisted of a qualitative study investigating the quality attributes of university foodservices through focus group interviews and a quantitative study evaluating service quality of university foodservices through a survey. Sixteen quality attributes were derived and customer satisfaction questionnaires included these 16 quality attributes with a five-point Likert scale. An Importance-Performance Analysis (IPA) model was applied in order to identify operational strategies necessary to improve service quality. The survey questionnaires were distributed to 600 university students enrolled in a university located in Kwangju and statistical analysis was performed on 555 surveys using an SPSS package. Overall customer satisfaction with the quality of university foodservices was relatively low (under 3.0) while the expectation was inclined to be high (over 4.0). The main reasons for using the university foodservice were given as inexpensive price (67.6%) and time saving (22.9%). A factor analysis of 16 quality attributes revealed two separate factors: food quality (Cronbach's alpha=0.911) and service quality (Cronbach's alpha=0.934). Variety of menu, convenient location, and sanitation of utensils and facilities were identified by an IPA model as factors needing improvement in operational strategies.

Importance-Performance Analysis(IPA) of Teachers' Perceptions Regarding Young Children's Rights (IPA 기법을 통한 교사들의 유아권리에 대한 중요도 및 수행도 인식 차이)

  • Goh, Eunkyoung;Kang, Jinju
    • Korean Journal of Childcare and Education
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    • v.14 no.4
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    • pp.1-24
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    • 2018
  • Objective: The purpose of this study was to investigate the differences in early childhood teachers' perceptions of the importance and institutional performance regarding young children's rights. Methods: 171 early childhood teachers responded to the questionnaires. The data were analyzed by using the paired sample t-test and the IPA graph to identify differences in the teachers' perceptions of the importance and performance of each right. Results: First, the teachers perceived the importance of children's rights to be high but low in institutional performance. The main effect of teaching years on the perception appeared significant only regarding performance of the rights of protection and participation. The main effect of teacher education experiences was significant in all areas except the importance of survival rights. The results from Two-Way ANOVA showed the two variables have no interaction. Second, the second quadrant of the IPA matrix displayed the items regarding initiative and autonomy of young children. Both inexperienced- and highly-experiencedteachers, when they had teacher education, recognized that the items related to participation rights should be further improved. Conclusion/Implications: We discussed the various ways in which children's rights should be improved and ways of improving teacher education according to teacher variables in order to promote young children's rights.

Comparative IPA of Hospital Choice Factors between Internal and External Customers of Regional General Hospital (지방 종합병원의 내·외부고객간 병원선택요인 중요도-성과도 비교)

  • Lee, Hyun-Sook
    • The Korean Journal of Health Service Management
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    • v.6 no.4
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    • pp.153-163
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    • 2012
  • The purpose of this study is to measure IPA(Importance Performance Analysis) of the hospital choice factors between internal and external customers at rural general hospital. This study was used 5 types of choice factor such as physical, human, accessibility, connection, and external image. Also, this study was used IPA which can be applied to identify the strengths and weaknesses quality attributes from customers' viewpoint by simultaneously evaluating importance and performance. IPA was assessed using a sample of 98 patients and 96 internal employees who work at C general hospital in Chunkcheongbuk-do. Data were collected with self-administered questionnaires from February 13 to March 30 in 2012 and analyzed SPSS 18 by using frequency, paired t-test and scatter plot graph. The results of IPA show that "Keep up the good work" quadrant was human factor and "Low Priority" quadrant was physical and connection factors between internal and external customers. The finding of this study will be applied to improve human service quality in administrative department of hospital. Also, this study presents primary data for correct decision making to authorities of local hospitals that have concern about hospital strategy. The implications of this study are discussed and areas for future research are presented.