• Title/Summary/Keyword: Representative Characteristics

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Representative Temperature Assessment for Improvement of Short-Term Load Forecasting Accuracy (단기 전력수요예측 정확도 개선을 위한 대표기온 산정방안)

  • Lim, Jong-Hun;Kim, Si-Yeon;Park, Jeong-Do;Song, Kyung-Bin
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.27 no.6
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    • pp.39-43
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    • 2013
  • The current representative temperature selection method with five cities cannot reflect the sufficient regional climate characteristics. In this paper, the new representative temperature selection method is proposed with the consideration of eight representative cities. The proposed method considered the recent trend of power sales, the climate characteristics and population distribution to improve the accuracy of short-term load forecasting. Case study results for the accuracy of short-term load forecasting are compared for the traditional temperature weights of five cities and the proposed temperature weights of eight cities. The simulation results show that the proposed method provides more accurate results than the traditional method.

Reaction of Lithium Cyanoaluminum Hydride with Selected Organic Compounds Containing Representative Functional Groups. Comparison of Reducing Characteristics between Lithium and Sodium Cyanoaluminum Hydrides

  • Cha, Jin-Soon;Yu, Se-Jin
    • Bulletin of the Korean Chemical Society
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    • v.30 no.7
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    • pp.1588-1592
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    • 2009
  • Lithium cyanoaluminum hydride (LCAH) was prepared by the metal cation exchange reaction of sodium cyanoaluminum hydride with lithium chloride in tetrahydrofuran. The reducing characteristics of LCAH were explored systematically by the reaction with selected organic compounds containing representative functional groups under the standardized conditions (tetrahydrofuran, 0 ${^{\circ}C}$). The reducing ability of LCAH was also compared with of the sodium derivative, sodium cyanoaluminum hydride (SCAH). Generally, the reducing behavior of LCAH resembles that of SCAH closely, but the reactivity of LCAH toward representative organic functional groups appeared to be stronger than that of SCAH. Thus, the regent reduces carbonyl compounds, epoxides, amides, nitriles, disulfides, carboxylic acids and their acyl derivatives to the corresponding alcohols or amines, at a relatively faster rate than that of SCAH. The cyano substitution, a strong election-withdrawing group, diminishes the reducing power of the parent metal aluminum hydrides and hence effects the alteration of their reducing characteristics.

Study on the Selection of Representative Pulse Wave

  • Kim, Jong-Yeol;Shin, Sang-Hoon
    • The Journal of Korean Medicine
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    • v.29 no.5
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    • pp.104-110
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    • 2008
  • Objectives : The purpose of this study is to develop the method of selecting representative pulse wave. Methods : The pulse waves were acquired at the right and the left Guan point(關部) with 1420 people who were apparently healthy. The shape agreement of right and left pulse wave and the floating-sinking ratio were compared with three cases, which were the pulse height based method, the pulse area based method, and the pulse time based method. Results : In the point of the shape accordance, the pulse time based method was the best, and the pulse area based method was the worst. In the point of the floating-sinking ratio, the pulse height based method was the worst, and the pulse time based method was the best. Conclusions : So, the pulse time based method was recommended for selecting the representative pulse wave. This study compared the selection methods of representative pulse using the physiological characteristics of pulse wave. Further studies are required, because the representative pulse wave is the main factor of determining the shape and the floating-sinking characteristic of the pulse wave.

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Experimental Investigation of the Characteristics of Mechanical Impedance of Korean- Seated Subjects (한국인의 앉은 자세에 대한 Mechanical Impedance의 실험적 연구)

  • 정완섭;김영태
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2003.05a
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    • pp.246-254
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    • 2003
  • This paper introduces attempts to obtain the 'representative' characteristics of the mechanical impedance of seated Korean subjects under vertical vibration. Individual responses of driving-point mechanical impedance obtained from forty-one Korean subjects are illustrated. Four kinds of vibration levels and three different sitting postures are selected to collect the responses of each subject. Those individual responses are used to estimate the 'mean' mechanical impedance, which may be expected to be a representative model to Korean subjects. Several interesting features of the estimated mechanical impedance are suggested and compared to those of ISO/DIS 5982.

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Selection on Representative Compound According to the Characteristics of the Change of VOC Concentration Indoor from the Newly Built House in Japan (일본 신축주택의 실내 VOC의 실태와 농도추이 특성에 의한 유형별 대표물질선정)

  • Yoo, Bok-Hee;Tanaka, Tatsuaki;Yoon, Chung-Sook
    • KIEAE Journal
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    • v.1 no.1
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    • pp.35-43
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    • 2001
  • The VOC, which were detected from the newly built house, exist as a certain number of types according to the characteristics of the change of VOC concentration indoors. In this paper, we aim to divide the VOC into types so that those with similar characteristics of the transition of their concentration are in the same group and select the representative compound according to each classified type, and to verify these processes statistically in order to verify and propose new method creating the representing index of the VOC concentration in indoor which is used in evaluation of the degree of air pollution. As a result, the characteristic of the change of VOC concentration in the indoor can be divided into three types. Type1; the group in which the concentration is relatively high right after the completion of the house, and then decreases rapidly. Type2; the group in which the concentration is relatively low right after the completion of the house, and then although it shows the tendency of increasing and decreasing repeatedly, it decreases overall. Type3 is the group, which show only one peak at a certain time during the measuring period. As the method like this was verified to have the statistical significance, the Ethylbenzene was selected as the representative compound of type1, and Styrene was selected as that of type2. Moreover, if considering transition of the VOC from the point of similarity, the research method of making the classification and the selection of the representative compound in this study are said to be significant method.

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Development of Korean Representative Headforms for the Total Inward Leakage Testing on Filtering Facepiece Respirators

  • Ah Lam Lee;Xin Cui;Hayoung Jung;Hee Eun Kim;Eun Jin Jeon;Hyungjin Na;Eunmi Kim;Heecheon You
    • Safety and Health at Work
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    • v.15 no.1
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    • pp.42-52
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    • 2024
  • Background: The lack of headforms that accurately reflect the head characteristics of Koreans and the demographic composition of the Korean population can lead to inadequate FFR testing and reduced effectiveness of FFRs. Method: Direct measurements of 5,110 individuals and 3D measurements of 2,044 individuals, aged between 9 and 69 years, were sampled from the data pool of Size Korea surveys based on the age and gender ratios of the Korean resident demographics. Seven head dimensions were selected based on the ISO 16976-2, availability of Size Korea measurements, and their relevance to the fit performance of FFRs. A principal component analysis (PCA) was performed using the direct measurements to extract the main factors explaining the head characteristics and then the main factors were standardized and remapped to 3D measurements, creating five size categories representing Korean head shapes. Lastly, representative 3D headforms were constructed by averaging five head shapes for each size category. Results: The study identified two main factors explaining Korean head characteristics by the PCA procedure specified in ISO 16976-2 and developed five representative headforms reflecting the anthropometric features of Korean heads: medium, small, large, short & wide, and long & narrow. Conclusion: This study developed representative headforms tailored to the Korean population for conducting total inward leakage (TIL) tests on filtering facepiece respirators (FFRs). The representative headforms can be used for TIL testing by employing robotic headforms to enhance the performance of FFRs for the Korean target population.

Characteristics of Hand Dimensions and Hand Scale for Koreans (한국인의 대표적 손 치수 특성과 손 스케일)

  • Kee, Do-Hyung
    • Journal of Korean Institute of Industrial Engineers
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    • v.37 no.1
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    • pp.55-63
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    • 2011
  • This study presents characteristics of representative five hand dimensions including hand length, medius finger length, hand circumference, hand breadth and hand thickness, and hand scales by gender and age for Koreans. The study was based on data of hand dimensions published in 2008 by Korean Agency for Technology and Standards. The hand dimensions of males were nearly the same as those of females until age of 12~13(10~11 in hand thickness), but the males' were larger than the females' from age group of 14~15 or 12~13. The growth of the hand dimensions was found until age of 12~13(14~15 in hand thickness) in females and 16~17 in males. After the age groups, the hand dimensions was almost the same irrespective of age groups. ANOVA was performed to investigate significant factors affecting hand dimensions. Representative five hand dimensions were significantly affected by gender and age, while they were not affected by occupation. Two hand scales were proposed depending upon gender, for easily using hand characteristics in design stage of hand relevant products. In addition, regression equations were provided for quantitatively predicting hand dimensions on the basis of representative five hand dimensions.

Evaluation of Material Characteristics by Micro/Nano Indentation Tests (마이크로/나노 압입시험에 의한 재료특성평가)

  • Lee, Hyung-Yil;Lee, Jin-Haeng
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.32 no.10
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    • pp.805-816
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    • 2008
  • The present work reviews the methods to evaluate elastic-plastic material characteristics by indentation tests. Especially the representative stress and strain values used in some papers are critically analyzed. The values should not only represent the load-depth curve, but also represent the whole of deformed material around the impression. We briefly introduce other indentation techniques to evaluate residual stresses, creep properties, and fracture toughness. We also review some technical problems that are related to the accuracy issues in indentation tests.

The Representative Body Type of Lower Body of Chinese Males in Their 20s (중국(中國) 20대(代) 남성(男性)의 하반신(下半身) 대표체형(代表體型) 연구(硏究))

  • Lee, So-Young;Shim, Boo-Ja
    • Journal of Fashion Business
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    • v.11 no.2
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    • pp.58-75
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    • 2007
  • This study held human measurement for 200 male subjects in their twenties in full age living in Ningbo City, Zhejiang Province in China. Their lower body types were classified and grouped according to shapes and sizes. Consequently, representative body type reflecting shapes, sizes, and characteristics were chosen and presented with their measurement values to be used as the basic data for slacks pattern making and fitness evaluation. The following are the results of the analysis: 1. Homogeneity analysis was given to determine the correspondence relationships among index types, indirect types, and size types. Index Type 1 (H-Round), Indirect Type 2 (Adjacent Straight Legs & Slight Slant of Lateral Lower Body), and Size Type 1 (Medium-Thick) were correlated; Index Type 2 (A-Trapezoid), Indirect Type 1 (Bow Legs & Slight Slant of Lateral Lower Body), and Size Type 3 (Small-Slim) were corresponded; Index Type 3 (A-Balance), Indirect Type 3 (Balance Legs & Large Slant of Lateral Lower Body), and Size Type 2 (Tall-Normal) were mutually related. 2. Mahalanobis distance based on each shape factor (index or indirect) and size factor (absolute) was obtained, while an index-absolute representative body type group (47 people, 24.4%) and an indirect-absolute representative body type group (45 people, 23.7%) were chosen, each reflecting shapes, sizes, and characteristics. 3. The representative body type group of lower body shapes of Chinese males in their 20s had average measurement values, such as 169.15cm (stature), 73.32cm (waist circumference), 75.76cm (omphalion waist circumference), 91.08cm (hip circumference), 106.02cm (outside leg length), 53.96cm (thigh circumference), and 74.42cm (crotch length).

Data Base Construction of Representative Practical Colors of Domestic Fashion Industry in Korea (국내 패션업계에서 활용되는 대표색의 Color Data Base 구현)

  • Choo Sunhyung;Cho Ju-Yeon;Kim Youngin
    • Journal of the Korean Society of Costume
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    • v.55 no.8 s.99
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    • pp.144-153
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    • 2005
  • The purpose of this study is to make a Web Color Data Base for practical design system for domestic fashion industry. The market segmentation was based on the results of the previous studies and the characteristics of fashion consumers. Finally, the 14,121 color samples are collected from the survey of 55 manufacturers of domestic fashion industry and 116 fashion brands of major department stores. These color samples are analyzed by the Munsell's H V/C and CIE L*a*b* value. The representative colors are selected concerning the density in CIE L*a*b* color space and the distance between the color samples. As a result, We suggested 2213 representative colors. Also, this color data was constructed on Web site. The data were sorted by the market, season and color code. In addition, the representative color sample book was made for the prototype of .