• Title/Summary/Keyword: the IPA

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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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Separation Purification Characteristics of Rinsing Solution in Semiconductor Process using Bigh Performance Polymer Membranes ( I ) (기능성 고분자막을 이용한 반도체 공정 세정액의 분리정제특성 (I))

  • Lee Jae-Dal;Hong Young-Ki;Ro Duck-Kil;Bae Kie-Seo
    • Textile Coloration and Finishing
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    • v.17 no.3 s.82
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    • pp.34-42
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    • 2005
  • In this work, a practical separation performance was investigated on aqueous alcohol solutions, especially for iso-propyl alcohol (IPA), which is usually used during the semi- conductor rinsing process. The removal of various substances from waste aqueous IPA solutions was carried out by microfiltration with $0.1\~1{\mu}$m pore size of mean diameter as a pre-filter. Permeability and molecular weight cut-off of the functional polysulfone(PSf) ultrafiltration membrane to purify waste aqueous IPA solutions were measured through the ultrafiltration test. The solute rejection of PSf membrane had $92\%$ in 1,000ppm aqueous PEG solution with PEG molecular weight 10,000, the molecular weight cut-off had 10,000. The IPA concentration on the $CMPA-K^+$ membrane performance using pervaporation module system could be increased from $95.04 wt\%$ to more than $98.50wt\%$ in about 9hr at operation temperature of $70^{\circ}C$ using the pervaporation module system.

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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Improvement of Supporting Services of Business Incubators by the Entrepreneurship Growth Stages Based on the IPA (IPA를 활용한 보육지원서비스에 대한 창업성장 단계별 개선방안)

  • Hyun-A Lee;Mi Yu;Tae-kyu Kwon
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.46 no.spc
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    • pp.54-60
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    • 2023
  • The government focuses on promoting start-ups, fostering ventures, and creating an ecosystem of start-ups through the formation of a strong growth environment for small businesses. This study provides academic and practical implications about ways of improving our business incubator's support service across stages of growth through IPA. To this end, an Importance-Performance Analysis (IPA) was conducted to analyze relationship and differences in importance and satisfaction of business incubator's support service support at business incubation center. These results present to provide the following academic and practical implications. The academic implications are the need for differences in support services for each phase of start-up growth. As factors that could increase the likelihood of successful start-up were identified in each phase of the start-up growth, important information needed for policy and strategy was provided. As a practical suggestion, the managers and expert groups are presented with sections to be opened for each start-up growth stage, minimum effort input, and areas to be maintained continuously. A systematic support plan is established and a foundation is provided for improvement measures in efficient start-up business incubator's support service.

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 using SN ratio (SN비를 이용한 중요도 만족도 분석)

  • Cho, Yong-Wook
    • Journal of the Korea Safety Management & Science
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    • v.16 no.4
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    • pp.397-403
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    • 2014
  • The objective of this study is to provide improved methodology based on the IPA method. One case studies are solved by the proposed method. this study present the method that give value to use SN(Signal-to-Noise) ratio in IPA. A case study of lecture satisfaction are solved by the proposed method and the existing method. Also, the result is compared with the existing method using Mean and the proposed method using SN ratio.

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.

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.

Phonetic Alphabet as a Pronunciation Guide (영어발음교육과 발음기호)

  • Kang, Yongsoon
    • Journal of English Language & Literature
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    • v.56 no.1
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    • pp.65-78
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    • 2010
  • The purpose of this paper is to suggest that the International Phonetic Alphabet be included in English curriculum and taught in English classroom. Current English curriculum for elementary and middle school students doesn't specify anything for the education of the IPA. The knowledge of IPA is essential for the students to study by themselves how to pronounce English words. The IPA, however, is either too little or too much to be taught at school. It is too little in that it doesn't tell us anything about allophones, the knowledge of which could enable us to get rid of foreign accents as much as possible. It is too much in that it can represent more than one sounds (e.g., /ɔ/ in American and British English). To overcome these drawbacks, it should be introduced gradually with the allophones in the same environments. The correct vowel sounds should be introduced with the aid of pronunciation dictionary so that the students could get their own vowel quality. Moreover, the IPA symbol should be adopted for the English textbooks.

A Pull System of the IPA in the Arae Hangul Wordprocessor (글틀<한글>에서 정밀 국제 음성 기호 쓰기)

  • KIM Zong-Su
    • MALSORI
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    • no.19_20
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    • pp.29-32
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    • 1990
  • The Arae Hangul wordprocessor is one of the most famous software in Korea. It is very useful to linguists In that it has various systems of foreign characters and enables us to edit enough new ones freely. It has already a broad system of the IPA, which cannot be used for narrow transcription. The writer proposes here a full system of the IPA revised to 1979, which you can get from the Phonetic Society of Korea or Hangul & Computer Co., Ltd., free of charge. To use the new system of the IPA in the Arae Hangul wordprocessor, you must replace six revised files: (1) SPECIAL2.SFT, (2) SPECIAL2.PFT, (3)SPECIAL2.PFT, (4)ASCII.SFT, (5)ASCII.PFT, (6)ASCII.LFT.

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