• Title/Summary/Keyword: Basic Concept

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Numerical Study on Auto-ignition and Combustion Emissions Using Gasoline/Ethanol Surrogates (휘발유/에탄올 혼합연료의 자연발화 및 연소배기가스 특성에 관한 수치적 연구)

  • Lee, Eui Ju
    • Fire Science and Engineering
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    • v.30 no.3
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    • pp.1-6
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    • 2016
  • More than five thousands transportation fires occurannually in Korea and the resulting destruction of property and loss of life is huge and results in traffic and environmental pollution. The recent development of automobile technology such as the hybrid concept and use of bio fuels makes fire protection even more difficult due to a lack of understanding of the new adapted system including vehicle engines. In this study, a numerical simulation was performed on a PSR (perfectly Stirred Reactor) to simulate an automobile engine and to clarify the effect of gasoline/ethanol surrogates as a fuel. The temperature, NOx and soot emissions were predicted to decrease with increasing ethanol content, but that of unburned hydrocarbons was found to increase dramatically. The result will provide not only the basic thermal characteristics for engines and their after-treatment systems, but also make it possible to assess the potential for fire events in these systems when an ethanol mixed fuel is used in gasoline vehicles.

RF Seeker LOS Rate Estimation Method using Covariance and Signal Management (공분산 및 신호관리를 이용한 RF탐색기 시선각 변화율 추정기법)

  • Moon, Gwan-Young;Jun, Byung-Eul
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.40 no.4
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    • pp.292-299
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    • 2012
  • The line-of-sight(LOS) rate is estimated using Kalman filter in Radio-Frequency(RF) seeker. For the two axis gimbaled seeker, proper system modeling is considered and the basic filter structure is set up. The main issue for Kalman filter is choosing the proper process and measurement noise. For the measurement process, the signal to noise ratio(SNR) and other components are introduced. To cope with the eclipse problem or other abnormal seeker status, the pseudo input signal concept is proposed. By conditioning abnormal signals, the LOS rate estimation performance is increased. The process noise is also an important factor in the propagation phase. The analytical approach on a process noise component is performed and a reliable region for the filter is calculated based on the eigenvalue analysis. Some numerical simulations are performed to check the validity of suggested algorithm.

A Study For the Standardization Design of Ginseng Cultivating Facility for the Improvement of Farming Environment (영농환경 개선을 위한 인삼재배사 표준화 디자인)

  • 신택균
    • Archives of design research
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    • v.16 no.1
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    • pp.93-102
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    • 2003
  • This thesis is a study for the standardization of the design of ginseng cultivating facility (also known as the sun off facility) for the improvement of farming environment. The core background of this study is to propose a basic study for introducing, for the first time, the modern ginseng cultivating facility that matches the position of korea as a main nation cultivating ginseng and to secure the production and quality value of Koryo Ginseng, which is a special world-level agricultural product of Korea, under the present WTO agricultural product open system. Right now, wood, rice straw, or vinyls, which are non-standardized or are for one-time use only are used. Therefore, as a concept of the design, 1 tried to revise the fact that these materials are being used to set up the facility repeatedly every year which is creating environmental pollution and wasting of our countries labor and resource. Concrete factors to be improved are as follows: First, standardization of the form and structure of mass production system; Second, introduction of new materials such as semi-permanent resin etc., for standardization of materials; 1 tried to make the above two factors into a shape based on a Korean image. As for the design, designed a standard unit model of the ginseng cultivation facility especially keeping in mind to design it so the facility can be freely connected and assembled according to the size and shape of the cultivation area.

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A Case Study aimed at Junior High School 3rd Grade Student's Understanding of Variability (중학교 3학년 학생들의 변이성 이해에 대한 사례 연구)

  • Song, Seon-A;Lee, Kyung-Hwa
    • School Mathematics
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    • v.9 no.1
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    • pp.29-44
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    • 2007
  • The aim of statistics education is to enhance statistical thinking. Variability is the key components of statistical thinking. The research has been reviewed preceding research about variability of data. Proceeding from what has been considered above, this research developed learning materials that investigated the concept of variability as it relates to Freudenthal's context by having students sort a particular context. The research is executed the case study evidently aimed at Junior High School 3rd Grade Student's Understanding of Variability. The study of variability in data can be an important start to reach a testing of statistical hypothesis; students reduce data and draw graphs by relating probability distribution to relative frequency and normal distribution. Thus, this study offers basic materials into developing both contents and methods of education need to consider with this sense of purpose held by students to achieve this goal.

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The Application of Make-up through Optical Illusion - Focused on Lineal Illusion -

  • Cho, Ko-Mi;Cho, Jin-A
    • Journal of Fashion Business
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    • v.7 no.6
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    • pp.57-66
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    • 2003
  • With the occurrence of interest in image-presentation that helps express one's individuality in several place in our society, it has affected make-up field. Now, make-up is getting to be recognized as a key role player that reflects our social and cultural concerns not only by presenting a appropriate one that is proper when to use and what for, but also presenting individualistic images that are able to express one's attractiveness free from a last plain concept that meant merely applying cosmetics to one's face is makeup. Like above, the reason that a change for consciousness of the function of make-up was possible is a noticeable outcome that results from the difference before and after make-up. In other word, with the help of Corrective Make-up that makes use of optical illusion, the analytic research for features could have been carried out systematically, therefore, women get to present their beauty of innate facial shape and features at their pleasure. The basic principles of the Corrective Make-up, which was introduced to satisfy the purpose of the existing make-up take advantage of lines and colors that are part of the optical illusion. The nature of direction and movement was expressed by the direction and angle of lines and the colors are also able to induce the variation of images depend on the whole color around them or contrastive color around. This thesis is mainly about optical illusion through lines that are part of elements that induce the optical illusion and deals with phenomena that occur when we apply lines that are part of design into the make-up. And this is written for the purpose of establishing the last basis of make-up more scientifically and systematically through the research for the variation when we apply the nature of lines into our features and deriving facial image variation from it. This is also for study into the role of make-up as for psychological effect that is able to make facial images look different when the optical illusion with possible visual errors is applied into it. In conclusion, we can say "Make-up is optical illusion through visual elements such as lines, surfaces, books, touch and so on."

Design of LB-DECK Based on Performance Evaluation (성능 평가에 근거한 LB-DECK의 설계)

  • Cho, Gyu Dae;Lho, Byeong Cheol;Cho, Hyun Chul
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.15 no.4
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    • pp.99-106
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    • 2011
  • This study performed research for improvement on basic concept of PBD applying suitable design method before and after LB-DECK composition. According to study, in this case, before composition, it can reduce minuteness cracks by increasing bending tensile strength utilizing polymer concrete, can expect sensuous effect, improve durability as to low permeability, and was evaluated that can reduce covering depth according as it. Also, because LB-DECK baseplate that apply the empirical design method composite is superior load resistance ability than general baseplate, safety is increased, it is expected to secure constructibility and economic performance at the same time because reinforcement arrangement method and reinforcement amount are fixed even if span effective span is increased at ultimate strength design method application.

The Necessity of Home Economics Education Teaching Materials in Secondary School (효과적인 중등학교 가정과 교육을 위한 교재연구의 필요성 -피복영역의 지도를 중심으로-)

  • 손원교
    • Journal of Korean Home Economics Education Association
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    • v.1 no.1
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    • pp.63-85
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    • 1989
  • The Change of environment related to human life, science, technology, economics and education level have much effect on home life. Therefore Home Economics Education have to get out of past trite concept that it is only a method to become good housewife and take the role to widen the human life and to grow creative power as a academic part of science. For these, Home Economics should become life education, life education of secondary school has to have relation to lifelong education. To achieve effective result from Home Economics Education, the object, system and methods of Home Economics Education, the object, system and methods of Home Economics Education have to be improved and teaching material has to be studied systematically. As an object of aboves and education planning in clothing is made for deep understanding the study of Home Economics Teaching Material. And to understand the real state, made some questions, had interview with 63-teaching in Kangweon province and show the results. 1) Tab 1~20 are the level of recognition about object, teaching content, time structure of secondary school. The object is recognized as cultural education and basic job education. 2) Tab 21~30 show the real state of textbook and study of it. To take effect from school lecture other teaching material except textbook is required. 3) Tab 31~40 are the result of sewing and handicraft practice. Sewing and handicraft needs much time and almost all time is used in practicing. 4) Tab 42~54 are the planning of textbook study for effective teaching, self-estimation and teaching material making is also considered. All above is collarless blouse’s planning. Base on above result, all objects of clothing life should be teached. For the development of Home Economics Education 1) Understanding and affection of teachers is required. 2) To solve indicated problem, national policy, education plan in school and education finance are fully supported. 3) More studies is required in Home Economics Education.

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Basic Study for Development of NATM Composite Lining Method (NATM Composite 라이닝 공법 개발을 위한 기초 연구)

  • Ma, Sang-Joon;Kang, Eun-Gu;Kim, Dong-Min;Shin, Joo-Yul
    • Journal of the Korean Geotechnical Society
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    • v.27 no.12
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    • pp.53-68
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    • 2011
  • This paper presents the fundamental parameters for designing the NATM Composite Lining to be used in NATM tunnel construction. Firstly, the concept of NATM Composite Lining behaviour is introduced and reviewed in construction-performance. For the fundamental study, the optimal mix ratio tests and backfill material property tests to develop high-quality composite lining (PC panel lining) are fundamentally carried out. And the light-weight foamed mortar which is used for backfill material is developed. Full-scale loading tests to verify a performance of the NATM Composite Lining is also performed. From this research, it is clearly found that the NATM Composite Lining is very applicable method to considerably increase the stability and constructability of tunnel structure.

A Study on Correlation Between Clothing Involvement and Brand Extension (의복관여와 상표확장과의 상관성 연구)

  • 정미재;이선재
    • Journal of the Korean Society of Clothing and Textiles
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    • v.21 no.7
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    • pp.1124-1138
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    • 1997
  • This study intended to investigate the concept of Clothing Involvement and Brand and to provide useful basic data for building on affective brand strategy. The purpose of this study is as follows: first, It is to measure the result of Brand Extension attitudes and Brand Extension items by clothing involvement (high involvement/low involvement). Second, It is to classify the factors of Clothing Involvement which suggested in theoretical research and to clarify correlation between clothing involvement factor and brand evaluation, brand extension attitudes. Third, It is to investigate the affect that clothing involvement, demographic variable and brand type on Brand Extension Evaluation. Subjects of this study were the adult women in Seoul, who were extracted by sampling randomly during the fall of 1995. Questionnaire was used as major method of gathering data. They were analyzed by the SAS method such as Frequency, Anova, Duncan, Correlation, multiple regression, Factor analysis. Main result of this study were as follows : 1. In brand extension attitude evaluation by high-involve group and low-involve group, quality, reputation and buying intension of brand extension attitudes showed significant difference. B brand extension attitudes and items of high-involve group was high compare to low-involve stoup. High-involve group evaluated watch, underwear, shoes and stocking of extension items highly, and there is no involvement difference of perfume, parasol, cushion. 2. In order to classify the dimension of Clothing Involvement, it was carried out factor analysis. 1 found that Clothing Involvement was composed of 4 factors, namely, interest - fashion.perceived risk symbolism. Correlation between clothing involvement and brand extension attitude was as followed; Interest factor of clothing involvement was correlated the existing brand attitude. Brand preference of the existing brand attitude was related the image of brand extension attitude, interest of advertising was the quality and the reputation-image was the buying intension. 3. For evaluation of a factor influenced on Brand Extension, it was produced multiple -regression test. Demographic variables and brand types had some influence of Clothing Involvement and Clothing Involvement had on brand extension. 27% of interest, 26% of symbolism was explained by brand types and 15% of fashion, 6% of perceived risk was explained by brand types, demographic variables. And, 10% of brand extension was explained by interest, fashion and symbolism.

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Performance Design of Boiler for Waste Heat Recovery of Engine Coolant by Rankine Steam Cycle (엔진 냉각수 폐열 회수를 위한 랭킨 스팀 사이클용 보일러의 성능 설계)

  • Heo, Hyung-Seok;Bae, Suk-Jung;Hwang, Jae-Soon;Lee, Heon-Kyun;Lee, Dong-Hyuk;Park, Jeong-Sang;Lee, Hong-Yeol
    • Transactions of the Korean Society of Automotive Engineers
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    • v.19 no.5
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    • pp.58-66
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    • 2011
  • A 2-loop waste heat recovery system with Rankine steam cycles for the improvement of fuel efficiency of gasoline vehicles has been investigated. A high temperature loop(HT loop) is a system to recover the waste heat from the exhaust gas, a low temperature loop(LT loop) is for heat recovery from the engine coolant cold relatively. This paper has dealt with a layout of a LT loop system, the review of the working fluids, and the design of the cycle. The design point and the target heat recovery of the LT boiler, a core part of a LT loop, has been presented and analytically investigated. Considering the characteristics of the cycle, the basic concept of the LT boiler has been determined as a shell-and tube type counterflow heat exchanger, the performance characteristics for various design parameters were investigated.