• Title/Summary/Keyword: assistant professor

검색결과 198건 처리시간 0.022초

The Cumulants of the Non-normal t Distribution

  • Hwang, Hark
    • Journal of the Korean Statistical Society
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    • 제5권2호
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    • pp.91-100
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    • 1976
  • The use of the statistic $t = \sqrt{n} (x-\mu)/S$, where $\bar{X) = \sum X_i/n, \mu = E(X_i), S^2 = \sum(X_i-\bar{X})^2/(n-1)$ in statistical inference is usually done under the assumption of normality of the population. If the population is not normally distributed the tabulated values of student t are no longer valid. The moments of t are obtained as a power series in $1/\sqar{n}$ whose coefficients are functions of the cumulants of X. The cumulants are obtained from the moments in the usual manner. The first eight cumulants of t are given up to terms of order $1/n^3$. The first eight cumulants of t are given up to terms of order $1/n^3$. These results extend those of Geary who gave the first six cumulants of t to order $1/n^2$.

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미국산 청바지 구매에 관한 소비자 태도 분석 (Consumer Attitude Toward Purchasing US Brand Jeans)

  • Kim-Jai-Ok
    • 복식
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    • 제28권
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    • pp.225-237
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    • 1996
  • The product evaluation and purchasing behavior of US brand jeans have been studied. The intrinsic and extrinsic cues are usually adopted to interpret the purchasing decison making processes. Among extrinsic cues price and brand name have been studied exten-sively but country-of-origin has not been examined in Korea. With the liberalization of retail industry foreign brands are aggressively penetrating in Korean pparel market. Since the penetration of imported apparel has increased tremendously lately the consumer attitude toward foreign produced clothing has great importance. The findings of the study were 1) Price was the most important among extrinsic cues ex-cept quality. Brand name was more important than store and country-of-origin. 2) The country image had significant influence to the preference as apparel production country. 3) The evaluation and willingness to buy of the jeans were greatly influenced by the be-havioral charcteristics of consumer variables. 4) The model to predict the willingness to buy of the jeans has been developed.

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Optimal Design of Silo System for Drying and Storage of Grains (I)-Simulation Modeling with SLAMSYSTEM

  • Chung, Jong-Hoon
    • 한국농업기계학회:학술대회논문집
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    • 한국농업기계학회 1993년도 Proceedings of International Conference for Agricultural Machinery and Process Engineering
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    • pp.952-965
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    • 1993
  • A simulation modeling is necessary for the optimal design of a rice processing plant, which consists of a facility (a silo system) of rice drying and storage and a rice mill plant. In a rice processing plant, the production scheduling and the decision on capcity of each unit based on a queuing theory is very important and difficult. In this study a process-oriented simulation model was developed for the design of a rice drying and storage system with SLAMSYSTEM. The simulation model is capable of simulating virtually all the processing activities and provides work schedules which minimize total processing time , mean flow time and bottleneck of the plant system and estimate drying time for a batch in a drying silo. Model results were used for determination the size and capacity of each processing unit and for analyzing the performance of the plant . The developed model was actually applied to construct a grain silo system for rice drying and storage.

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The Structure, Growth and Equilibrium of the Money Market in Korea

  • Oh, Kwan-Chi
    • Journal of the Korean Statistical Society
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    • 제4권2호
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    • pp.113-125
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    • 1975
  • The money market has been existing in various forms for a long time. Until 1972, however, the market had supplied mainly short-term loans of commercial banks and loans of informal money lenders to business corporations. There was no market for notes and commercial papers of business corporations. Consequently, business corporations had to rely primarily upon commercial banks for short-term credit loans to supplement their working capital. The interest rate on loans of commercial banks had been set below a free market equilibrium rate and thereby, generated excess demands for the loans. Unsatisfied potential borrowers thus had to turn to informal money lenders for short-term cerdit loans of prohibitively high interest rate. Since 1972 investment and finance companies have been operating in the money market and their role in mobilizing short-term loans is increasing. This paper aims at estimating the equilibrium size of the money market.

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차단벽을 이용한 DNAPL 오염지역의 복구 (Remediation of A DNAPL Contaminated Site Using Containment WALL)

  • Lee, Kwang-Yeol;Joo, Wan-Ho
    • 한국지하수토양환경학회:학술대회논문집
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    • 한국지하수토양환경학회 1998년도 공동 심포지엄 및 추계학술발표회
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    • pp.81-85
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    • 1998
  • In the present study, the design method of containment walls is proposed by utilizing an existing site. The selected remedy for the Source Area of Operable Unit 2 at Hill Air Force Base stipulated containment of the pure-phase trichloroethylene contamination. The in-place-mixed wall construction was selected because of the irregular topography, small area of the site, and the requirement to reach depths of greater than 90 feet below ground surface. Bench-scale compatibility studies were performed for the containment wall mix design on three commercial bentonite clays. The samples were subject to screening tests and long-term tests for evaluation of changed soil properties when exposed to the contaminated groundwater.

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Neuro-Fuzzy Algorithm for Nuclear Reactor Power Control : Part I

  • Chio, Jung-In;Hah, Yung-Joon
    • 한국지능시스템학회논문지
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    • 제5권3호
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    • pp.52-63
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    • 1995
  • A neuro-fuzzy algorithm is presented for nuclear reactor power control in a pressurized water reactor. Automatic reacotr power control is complicated by the use of control rods because of highly nonlinear dynamics in the axial power shape. Thus, manual shaped controls are usually employed even for the limited capability during the power maneuvers. In an attempt to achieve automatic shape control, a neuro-fuzzy approach is considered because fuzzy algorithms are good at various aspects of operator's knowledge representation while neural networks are efficinet structures capable of learning from experience and adaptation to a changing nuclear core state. In the proposed neuro-fuzzy control scheme, the rule base is formulated based ona multi-input multi-output system and the dynamic back-propagation is used for learning. The neuro-fuzzy powere control algorithm has been tested using simulation fesponses of a Korean standard pressurized water reactor. The results illustrate that the proposed control algorithm would be a parctical strategy for automatic nuclear reactor power control.

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Integrated Damage Identification System for large Structures via Vibration Measurement

  • JEONG-TAE KIM;SOO-YONG PARK;JAE-WOONG YUN;JONG-HOON BAEK
    • International Journal of Ocean Engineering and Technology Speciallssue:Selected Papers
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    • 제4권1호
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    • pp.31-37
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    • 2001
  • In this paper, an integrated damage identification system (IDIS) is proposed to locate and size damage in real structures. The application of the IDIS to real structures includes the measurement of modal responses, the construction of damage-detection models, and the implementation of measurements and models into the damage-detection process. Firstly, the theory of the damage identification method is outlined. Secondly, the schematic and each component of the IDIS are described. Finally, the practicality of the IDIS is verified from experiments on two different bridge-models, a model plate-grider and a model truss.

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A New Decomposition Method for Parallel Processing Multi-Level Optimization

  • Park, Dong-Hoon;Park, Hyung-Wook;Kim, Min-Soo
    • Journal of Mechanical Science and Technology
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    • 제16권5호
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    • pp.609-618
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    • 2002
  • In practical designs, most of the multidisciplinary problems have a large-size and complicate design system. Since multidisciplinary problems have hundreds of analyses and thousands of variables, the grouping of analyses and the order of the analyses in the group affect the speed of the total design cycle. Therefore, it is very important to reorder and regroup the original design processes in order to minimize the total computational cost by decomposing large multidisciplinary problems into several multidisciplinary analysis subsystems (MDASS) and by processing them in parallel. In this study, a new decomposition method is proposed for parallel processing of multidisciplinary design optimization, such as collaborative optimization (CO) and individual discipline feasible (IDF) method. Numerical results for two example problems are presented to show the feasibility of the proposed method.

단섬유 보강 복합재료에서의 열탄성 거동에 관한 해석 (An lnvestigation of the thermoelastic Behavior in Short Fiber Reinforced Composite Materials)

  • 김홍건
    • 한국생산제조학회지
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    • 제6권3호
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    • pp.89-95
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    • 1997
  • A simulation to investigate the thermal behavior in short fiber or whisker reinforced composite materials has been performed for the application to the thermoelastic stress analysis using Finite Element Method (FEM). To obtain the internal field quantities of composite material, the procedure of micromechanical modeling and the principle of virtual work were implemented. For the numerical illustration, an aligned axisymmetric single fiber model has been employed to assess field quantities. It was found that the proposed simulation methodology for thermoelastic stress analysis is applicable to the complicated inhomogeneous solid for the investigation of micromechanical thermoelastic behavior.

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Symbolic Meanings in Postmodern Fashion Advertisements

  • Lee, Jaeil
    • The International Journal of Costume Culture
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    • 제7권1호
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    • pp.17-27
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    • 2004
  • Using semiotic analysis, visual images in selected postmodern fashion advertisements were analyzed. Semiotics is the study of the structure of the meanings of signs. Semiotic analysis involves deconstruction, and thus draws on the researcher’s value-mediated introspection and subjective interpretation of texts i.e., ads). Through deconstruction, culturally assigned meanings, which represent consumers and culture, were revealed. Postmodern characteristics including open interpretation, use of the human body as an object, multi page format, new mood, black and white scenes, use of real people, and new ideology were identified in the ads. The importance of analyzing visual images in fashion ads was stressed in the findings of the study, as was the importance of educating consumers on how to read the visual images.

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