• 제목/요약/키워드: Five Transformations

검색결과 25건 처리시간 0.025초

우리나라 주요지점에 있어서의 강우해석에 관한 수문통계학적 연구

  • 이원환
    • 물과 미래
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    • 제5권2호
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    • pp.30-43
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    • 1972
  • The paper describes on the hydrologic analysis of point rainfall data of the three major areas, such as in Seoul, Pusan and Taegu. Scheme of the paper is analyzed five research cases. Contents of the analysis are carried out five kinds of transformed variables for determination of rainfall distribution types and two kinds of reliability tests on unusual(extraordinary) values each rainfall durations:short durations, long durations, long durations, monthly and yearly. Rainfall depth probability had been computed methods of hydrologic amounts analysis namely logarithmic transformations or Gumbel-Chow method and so on, but in this paper it is calculated log xi, n-square root transformations by using normal distribution function and normalization of rainfall distributions is examined graphical tests and $X^2-test$(chi-square test). Furthermore, rainfall depth probability is calculated taking into account the safty factors of project life of hydraulic structures. We think it is advanced contents that considering priceless experiences, the life of structures, conditions and more problems of planning engineers and designers, proposed rainfall amounts(proposed values) are presented charts or figures.

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설계갈수량의 유도를 위한 수문통계학적 연구(II) (Statistical Studies on the Derivation of Design Low Flows (II))

  • 이순혁;박명근;박종국
    • 한국농공학회지
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    • 제34권4호
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    • pp.39-47
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    • 1992
  • Derivation of reasonable design low flows was attempted by comparative analysis of design low flows was derived by Power and SMEMAX transformations for the normalizations of skewed distribution and by Type m extremal distribution presented in the first report of this study with annual low flows in the five watersheds of main river basins in Korea. The results were anslyzed and summarized as follows. 1.Basic statistics of annual low flows for the selected watersheds were calculated by using Power and SMEMAX transformations. 2.Power thansformation has found to be the best for the normalization of skewed distribution among others including log, square root and SMEMAX transformations. 3.Design low flows for the selected watersheds were derived by the Power and SMEMAX transformations. 4.Judging by the relative suitabilities of the Type III extremal distribution, Power and SMEMAX transformation, it was found that design low flows of all methods are closer to the observed data within 10 years of the return period and those of Power transformation can be acknowledzed as a reasonable one among others from the viewpoint of the median between values of Type m extremal distribution and SMEMAX transformation in addition to closing the observed than others over 10 years of the return period.

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A View on the Validity of Central Limit Theorem: An Empirical Study Using Random Samples from Uniform Distribution

  • Lee, Chanmi;Kim, Seungah;Jeong, Jaesik
    • Communications for Statistical Applications and Methods
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    • 제21권6호
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    • pp.539-559
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    • 2014
  • We derive the exact distribution of summation for random samples from uniform distribution and then compare the exact distribution with the approximated normal distribution obtained by the central limit theorem. To check the similarity between two distributions, we consider five existing normality tests based on the difference between the target normal distribution and empirical distribution: Anderson-Darling test, Kolmogorov-Smirnov test, Cramer-von Mises test, Shapiro-Wilk test and Shaprio-Francia test. For the purpose of comparison, those normality tests are applied to the simulated data. It can sometimes be difficult to derive an exact distribution. Thus, we try two different transformations to find out which transform is easier to get the exact distribution in terms of calculation complexity. We compare two transformations and comment on the advantages and disadvantages for each transformation.

히스토그램 시퀀스 구성을 위한 공간 지역성 보존 척도 (Spatial Locality Preservation Metric for Constructing Histogram Sequences)

  • 이정곤;김범수;문양세;최미정
    • 정보화연구
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    • 제10권1호
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    • pp.79-91
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    • 2013
  • 본 논문은 히스토그램 시퀀스(histogram sequence)에 저차원 변환을 적용할 때, 어떤 공간 채움 곡선(space filling curve: SFC)의 성능이 가장 좋은지를 판단하는 체계적인 평가방법을 제안한다. 히스토그램 시퀀스는 이미지를 주어진 SFC에 따라 시계열 형태로 표현한 것을 말한다. 히스토그램 시퀀스는 매우 고차원이므로 저장 및 검색이 매우 어렵다. 효율적인 저장 및 검색을 위해서 시계열 저차원 변환의 하한을 사용할 수 있는데, 이 하한의 성능은 SFC의 종류에 따라 큰 영향을 받게 된다. 본 논문에서는 히스토그램 시퀀스를 저차원 변환할 때 어떤 SFC의 성능이 좋은지를 평가하기 위해, "히스토그램 시퀀스에서 엔트리들이 인접하면 이미지에서도 해당 셀들이 인접해야 한다"는 공간지역성(spatial locality)의 개념을 제안한다. 다음으로, 공간 지역성을 정량적으로 평가할 수 있는 공간 지역성 보존 척도(spatial locality preservation metric)를 제안하고, 이를 계산하기 위한 정형적인 방법을 제시한다. 본 논문에서는 공간 지역성 보존 척도 측면에서 총 다섯 가지의 SFC를 평가하고, 이 평가 결과가 실제 이미지 매칭의 저차원 변환 성능 평가와 유사함을 확인한다. 또한, 저차원 변환 기반의 k-NN(k-nearest neighbors) 검색을 실험하여, 공간 지역성 보존 척도가 가장 낮은 힐버트-오더가 k-NN 검색에서도 가장 좋은 성능을 보임을 통해, 제안한 공간 지역성 보존 척도의 유용성을 입증한다.

개인용 컴퓨터를 이용한 전개도 작성에 관한 연구 (Constructing the Development of Solids by Personal Computer)

  • 채희창;정인성
    • 대한기계학회논문집
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    • 제14권2호
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    • pp.367-375
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    • 1990
  • A data structure representing 3-D objects was designed for the personal computer. It is very simple to be used in the personal computers which have small memory and low speed. A homogeneous transformation for developing 3-D objects was derived. Each developing procedure consists of five transformations : one translational-three rotational-one translational. Developing a solid is a creative work. So the results of developing vary with the order of surfaces to be developed. One method to reduce the length of seam was considered. The programs used in this study were written in Pascal and Assembly and a modeller that generates 3-D primitives was included. This program is an interactive dual-screen system. While all the menus in Korean are displayed at the monochrome monitor, the development figures with projective views are drawn at the color monitor. The program has wide applications for plate works.

중등 학교수학의 교수-학습과 그래핑 계산기 활용과의 관계에 대한 고찰

  • 조정수
    • East Asian mathematical journal
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    • 제26권2호
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    • pp.165-177
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    • 2010
  • The purpose of this study is to review previous studies regarding the relationship between graphing calculators usage and teaching and learning school mathematics and to suggest practical implications for further research in mathematics education. Through reviewing the total of 21 studies five subsections are divided in order to gain the answers to the research questions. The results of this study are as follows: students typically used graphing calculators in drawing graphs of functions, and they used graphing calculators as a tool for calculations, transformations, data collection and analysis, visualization, and checking. The implications for further research are suggested corresponding to these results.

Fast speaker adaptation using extended diagonal linear transformation for deep neural networks

  • Kim, Donghyun;Kim, Sanghun
    • ETRI Journal
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    • 제41권1호
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    • pp.109-116
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    • 2019
  • This paper explores new techniques that are based on a hidden-layer linear transformation for fast speaker adaptation used in deep neural networks (DNNs). Conventional methods using affine transformations are ineffective because they require a relatively large number of parameters to perform. Meanwhile, methods that employ singular-value decomposition (SVD) are utilized because they are effective at reducing adaptive parameters. However, a matrix decomposition is computationally expensive when using online services. We propose the use of an extended diagonal linear transformation method to minimize adaptation parameters without SVD to increase the performance level for tasks that require smaller degrees of adaptation. In Korean large vocabulary continuous speech recognition (LVCSR) tasks, the proposed method shows significant improvements with error-reduction rates of 8.4% and 17.1% in five and 50 conversational sentence adaptations, respectively. Compared with the adaptation methods using SVD, there is an increased recognition performance with fewer parameters.

Research towards New Innovation Strategies in Korea via Focused Group Method

  • Park, Sung-Uk;Kwak, Jae-Won;Kim, Hyun-Cheol
    • Asian Journal of Innovation and Policy
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    • 제11권2호
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    • pp.222-237
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    • 2022
  • As the COVID-19 pandemic crisis left developing countries with economic setbacks, it is high time to highlight that innovative technologies lead the digital economy. The big powers including the United States and China are already implementing industrial policies that involve large-scale fiscal expenditures to secure the lives and safety of their people. To prepare for the future up to 2025, this paper reflects opinions of industry-academia-research experts regarding changes in the external environment and industry trends. By reflecting results of focus group interviews and changes in the external environment and industry trends, a new high-level 5X strategy (Digital Transformation, Energy Transformation, Bio Health Transformation, Supply Chain Transformation, and Research Transformation) to solve national tasks required for the existing ten policy demand fields and ten agenda during lower-level policy implementation stages were derived.

Robust decentralized control of structures using the LMI Hcontroller with uncertainties

  • Raji, Roya;Hadidi, Ali;Ghaffarzadeh, Hosein;Safari, Amin
    • Smart Structures and Systems
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    • 제22권5호
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    • pp.547-560
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    • 2018
  • This paper investigates the operation of the $H_{\infty}$ static output-feedback controller to reduce dynamic responses under seismic excitation on the five-story and benchmark 20 story building with parametric uncertainties. Linear matrix inequality (LMI) control theory is applied in this system and then to achieve the desired LMI formulations, some transformations of the LMI variables is used. Conversely uncertainties due to material properties, environmental loads such as earthquake and wind hazards make the uncertain system. This problem and its effects are studied in this research. Also to decrease the transition of large amount of data between sensors and controller, avoiding the disruption of whole control system and economy problems, the operation of the decentralized controllers is investigated in this paper. For this purpose the comparison between the performance of the centralized, fully decentralized and partial decentralized controllers in uncoupled and coupled cases is performed. Also, the effect of the changing the number of stories in substructures is considered. Based on the numerical results, the used control algorithm is very robust against the parametric uncertainties and structural responses are decreased considerably in all the control cases but partial decentralized controller in coupled form gets the closest results to the centralized case. The results indicate the high applicability of the used control algorithm in the tall shear buildings to reduce the structural responses and its robustness against the uncertainties.

헨릭 빕스코브 컬렉션에 나타난 패션 인스톨레이션의 표현 특성 (The Expressive Characteristics of Fashion Installation in Henrik Vibskov Collection)

  • 고현진
    • 복식
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    • 제65권6호
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    • pp.133-147
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    • 2015
  • The aim of this study is to review the creative fashion installation of Henrik Vibskov, Danish designer. Its intention is to contribute useful information for more innovative fashion presentation. As a research method, document and case study were performed and his collections from 2004 F/W to 2016 S/S were analyzed. In fashion installation, the designer puts objects in meaningful spaces in order to convey a certain message, to make an integrated artwork, and to interact with spectator. It has been used in fashion exhibitions, as well as in the set design of fashion performance and fashion show. The results were as follows. Henrik Vibskov's fashion installation has three features, which are 1)conceptual theme approach that communicates a twisted and metaphoric message, with a poetic and interesting show title, 2) surrealistic scenography that plays with fragmentation of the human body, clustering of plastic and symbolic objects, innovative color transformations, and visual trickery between figures and the background, and 3) setting for multisensory performance that makes spectators interact by making artistic objects and surroundings, which stimulates the five senses. Henrik Vibskov's fashion installation can exist as an independent artwork, and not just as a supporting piece for a fashion show. It has both artistic and fashionable values, and can be an effective fashion presentation communicating his conceptual fashion themes.