• Title/Summary/Keyword: Standard variation

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A Study on Energy Requirement Variation According to Energy Efficiency Rating Evaluation and Design Variable of Standard Design of Rural Houses (농촌주택표준설계도 에너지효율등급평가 및 설계변수에 따른 에너지소요량 변화에 관한 연구)

  • Park, Mi-Lan;Ryoo, Yeon-Su;Choi, Jeong-Man;Seo, Hye-Won
    • Journal of the Korean Institute of Rural Architecture
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    • v.19 no.2
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    • pp.9-16
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    • 2017
  • The study analyzed the heat losses and the building energy efficiency grade by the energy simulation using the ENERGY# and ECO2 programs for the three types of Standard design of rural houses. It was calculated the energy efficiency rating by the ECO2 program for the rural housing standard design, and the energy demand and the energy consumption by each factor were compared and analyzed. And it analyzed energy consumption by element of each house by ENERGY # program. As a result, first in the evaluation of the energy efficiency grade of buildings by the ECO2 program, the rating for primary energy requirement for the housing newly built by the standard design of rural house is expected to range from 2 to 4 with 189.3 to $238.7kWh/m^2.a$. Second, the energy loss of each part of standard design of rural housing occurs in the order of ventilation 39%, window 33%, outer wall 14%, roof 9%, bottom 5%, and energy loss through ventilation and window occurs more than 70%. Third, the most beneficial effects on the energy efficiency grade is obtained the lowest grade of all three types by 2 when the lowering of the window and door heat transmission rate and the lowering of the light density, and the heat exchange ventilation device is not installed. Fourth, in the standard design of rural housing, the energy demand is occupied by heating > hot water > lighting order, and the order of the weight is changed in order of heating > lighting > ventilation > hot water. Fifth, building energy efficiency assessment system needs to establish policy for fixing rural housing energy as a practical device to ensure energy performance and quality.

A Study on Improvement of Standard Criteria for Tactile Walking Surface Indicators (시각장애인 점자블록의 규격기준 개선방안 연구)

  • Shin, Dong Hong;Kang, Byoung Keun;Park, Kwang Jae;Kim, Sang Woon
    • Journal of The Korea Institute of Healthcare Architecture
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    • v.21 no.1
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    • pp.67-76
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    • 2015
  • Purpose : The current tactile walking surface indicators have not been easily accessible to blind and vision-impaired people due to unexpected variation of walking environment and walking behavior of transportation poor. Moreover, those indicators frequently cause the inconvenience to transportation users' walking. Thus, this study aims to investigate the improvement of tactile walking surface indicators, by comparing and analyzing findings from the relevant research. Results from this study contribute to suggest the better standard criteria of tactile walking surface indicators for transportation users, especially blind and vision-impaired people, the handicapped, the child and the elderly and weak, providing the secure and convenient circumstance for walking. Method : This study presents the problems about the standard criteria of tactile walking surface indicators via the examination of finding from the past studies. For example, we examine all standard criteria, focusing on shapes, colors and qualities of materials used for Tactile Walking Surface Indicators. Then, the present study suggests the improvement of standard, which apply to the current walking environment practically and reasonably. Results : To improve the current condition of tactile walking surface indicators, the analysis on international and domestic standard criteria need to be conducted. Findings from these analyses helps to suggest the better criteria for the interval between projecting points of tactile walking surface indicators, effective perceived range of walking road, and the brightness contrast between tactile walking surface indicators and finishing materials. Implication : The suggested standard criteria of tactile walking surface indicators need to be tested by transportation users, and the practical instructions of establishing tactile walking surface indicators should also be developed.

Evaluation of Artifact and Noise in the Standard and MAR Algorithms with Variation of Examination Conditions of CT (Standard와 MAR 알고리즘에서 CT 검사조건 변화에 따른 인공물과 노이즈 평가)

  • Kim, Young-kuen;Yang, Sook;Wang, Tae-uk
    • Journal of radiological science and technology
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    • v.43 no.2
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    • pp.79-85
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    • 2020
  • The influence of metal artifact in CT image depends on the type of metal materialsm, the reconstruction algorithm, and scan parameters. The presence of metal artifacts was quantitatively evaluated by applying the standard and MAR algorithms through the phantom study. In the change of tube voltage applied the standard algorithm, metal artifact decreased to 44.9% for 80 vs 120 kVp, 24% for 100 vs 120 kVp, while the image taken at 140 kVp increased the artifact by 19% compared to 120 kVp. When the tube current was increased from 100 to 300 mA, there was no significant difference in the CT value and noise. Black band and white strike artifacts occurred up to 65.9% in the adjacent ROI of the metal driver, whereas titanium screw produced lesser metal artifact than that of the metal driver. The combination of 120kVp or higher tube voltage-standard algorithm was effective in removing black band artifacts as well as white streak by high density materials. However, MAR reconstruction algorithm was useful in improving image quality under the environment of low kVp and high density materials, without increase of radiation exposure.

The Effect of Header and Channel Angle Variation on Two-Phase Flow Distribution at Multiple Junctions (헤더-채널 분기관의 각도변화가 2상 유동 분배에 미치는 영향에 대한 연구)

  • Lee, Jun Kyoung
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.27 no.11
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    • pp.559-566
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    • 2015
  • The main objective of this work is to experimentally investigate the effect of angle variation on the distribution of two-phase flow at header-channel junctions. The cross-sections of the header and the channels were fixed at $16mm{\times}16mm$ and $12mm{\times}1.8mm$, respectively. Air and water were used as the test fluids. Four different header-channel positions were tested : Vertical header with Horizontal channels (case VM-HC), Horizontal header with Horizontal channels (case HM-HC), Horizontal header with Vertical Downward channels (case HM-VDC), and Horizontal header with Vertical Upward channels (case HM-VUC). In all cases, liquid flow distribution tended to decrease gradually in the upstream header region. However, in the downstream region, different trends could be seen. The reason for these different tendencies were identified by flow visualization in each case. The standard deviations for the liquid and gas flow distribution in each case were calculated, and the case of VM-HC had the lowest values compared to other cases because of the symmetrically distributed liquid film and strong flow recirculation near the end plate.

An Evaluation of Probabilistic Strain-Life Curve in Polyacetal (폴리아세탈 소재의 확률론적 변형률-수명선도 평가)

  • Jang, Cheon-Soo;Kim, Chul-Su;Park, Bum-Gyu;Kim, Jung-Kyu
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.30 no.11 s.254
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    • pp.1417-1424
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    • 2006
  • In order to evaluate variation of fatigue life of mechanical components including engineering plastics, it is important to estimate probabilistic strain-life curves to accurately define the variation of fatigue characteristics. This paper intends to provide new assessment of P-$\varepsilon$-N (probabilistic strain-life curves) for considering the variation of fatigue characteristics in polyacetal. The fatigue strain controlled tests were conducted under constant 50% humidity and room temperature condition by a universal testing machine at strain ratio, R=0. A practical procedure is introduced to evaluate probabilistic strain-life curves. Three probabilistic distributions were used for generating P-$\varepsilon$-N curves such as normal, 2-parameter and 3-parameter Weibull. In this study, 3-parameter Weibull distribution was found to be most appropriate among assumed distributions when the probability distributions of the fatigue characteristic were examined using chi-square and Kolmogorov-Smirnov test. The more appropriate P-$\varepsilon$-N curves for these materials are generated by the proposed method considering 3-parameter Weibull distribution.

A Comparative Evaluation of Sampling Methods for Airbone Mercury Concentration (공기중 수은 농도의 측정방법에 대한 비교평가연구)

  • Park, Ju Young;Kim, Kwang Jong;Paik, Nam Won
    • Journal of Korean Society of Occupational and Environmental Hygiene
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    • v.5 no.2
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    • pp.184-192
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    • 1995
  • This study was performed to evaluate methods for determination of airbone mercury in industrial environments. Three methods, such as Hopcalite method, passive monitoring method and Jerome method were evaluated at two (2) fluorescent lamp manufacturing Plants in Korea during a period from May 24 to May 31, 1994 and the result are as follows: 1. The average were concentrations of airbone mercury were $26{\mu}g/m^3$ by Hopcalite method, $25{\mu}g/m^3$ by passive monitoring method, and $38{\mu}g/m^3$ by the Jerome method, respectively, which were below the permissible exposure limit of $50{\mu}g/m^3$ established by both the Korean Ministry of Labor and ACGIH. However, 12 out of 49 cases(24.4%) in plant A and 2 out of 31 cases(6.5%) in plant B were in excess of the standard. 2. The relationship between the results by Hopcalite method and the passive monitoring method was significant(r=0.892). 3. The variation among three results by eath of three methods were different by process. The highest variation was determined at quality control process("process b") which invoved in large variation of concentrations. 4. When short term high concentrations were produced, the Hopcalite method was more efficient then the passive method.

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Somatotype Characteristics of Elementary School Girls (Part I) -Focusing somatotype changing charcteristics on each grade group- (학령기 여아의 체형 특성(제1보) -학령기별 체형 변이 특성을 중심으로-)

  • 장정아;권영숙
    • Journal of the Korean Society of Clothing and Textiles
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    • v.23 no.7
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    • pp.941-952
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    • 1999
  • The purposes of this study were to provide the fundamental data on elementary school girls' somatotype for their clothing construction by contemplating the stage of physical growth dividing into the period of school age and characterizing the variation of body type according to the school age. The results are as follows : 1. Form the results of one-way variables analysis and multiple comparson test(Duncan's test) classification of the period school age can be divided into 'early grade(1 2 grade)' ' middle grade(3 4 grade)' and 'later grade(5 6 grade)' 2. As the results of analyzing Mean Coefficient of Variation and Standard Deviation graph for direct and indirect measurments and index especially of the Coefficient Variation that explain individual difference of growth the items of height indicates individual difference related with height of lower body of early grade group the items of length individual difference related with length of upper body of later grade group and the items of circumference make little difference. The items of anagle makes pretty higher value that direct measurements and especially in lower angle of chest make a distinctive difference, This fact proves that children's somatotype change from the belly part extruded forwards of early and middle grade to the upper body part slanted slightly forward of later grade.

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Silver nanowire-containing wearable thermogenic smart textiles with washing stability

  • Dhanawansha, Kosala B.;Senadeera, Rohan;Gunathilake, Samodha S.;Dassanayake, Buddhika S.
    • Advances in nano research
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    • v.9 no.2
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    • pp.123-131
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    • 2020
  • Conventional fabrics that have modified in to conductive fabrics using conductive nanomaterials have novel applications in different fields. These of fabrics can be used as heat generators with the help of the Joule heating mechanism, which is applicable in thermal therapy and to maintain the warmth in cold weather conditions in a wearable manner. A modified fabric can also be used as a sensor for body temperature measurements using the variation of resistance with respect to the body temperature deviations. In this study, polyol synthesized silver nanowires (Ag NWs) are incorporated to commercially available cotton fabrics by using drop casting method to modify the fabric as a thermogenic temperature sensor. The variation of sheet resistance of the fabrics with respect to the incorporated mass of Ag NWs was measured by four probe technique while the bulk resistance variation with respect to the temperature was measured using a standard ohm meter. Heat generation profiles of the fabrics were investigated using thermo graphic camera. Electrically conductive fabrics, fabricated by incorporating 30 mg of Ag NWs in 25 ㎠ area of cotton fabric can be heated up to a maximum steady state temperature of 45℃, using a commercially available 9 V battery.

Face and Facial Feature Detection under Pose Variation of User Face for Human-Robot Interaction (인간-로봇 상호작용을 위한 자세가 변하는 사용자 얼굴검출 및 얼굴요소 위치추정)

  • Park Sung-Kee;Park Mignon;Lee Taigun
    • Journal of Institute of Control, Robotics and Systems
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    • v.11 no.1
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    • pp.50-57
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    • 2005
  • We present a simple and effective method of face and facial feature detection under pose variation of user face in complex background for the human-robot interaction. Our approach is a flexible method that can be performed in both color and gray facial image and is also feasible for detecting facial features in quasi real-time. Based on the characteristics of the intensity of neighborhood area of facial features, new directional template for facial feature is defined. From applying this template to input facial image, novel edge-like blob map (EBM) with multiple intensity strengths is constructed. Regardless of color information of input image, using this map and conditions for facial characteristics, we show that the locations of face and its features - i.e., two eyes and a mouth-can be successfully estimated. Without the information of facial area boundary, final candidate face region is determined by both obtained locations of facial features and weighted correlation values with standard facial templates. Experimental results from many color images and well-known gray level face database images authorize the usefulness of proposed algorithm.

A Preliminary Study on the Repeatability of Facial Feature Variables Used in the Sasang Constitutional Diagnosis (체질진단에 활용되는 안면 특징 변수들의 반복성에 대한 예비 연구)

  • Roh, Min-Yeong;Kim, Jong-Yeol;Do, Jun-Hyeong
    • Journal of Sasang Constitutional Medicine
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    • v.29 no.1
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    • pp.29-39
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    • 2017
  • Objectives Facial features can be utilized as an indicator of Korean medical diagnosis. They are often measured by using the diagnostic device for an objective diagnosis. Accordingly, it is necessary to verify the reliability of the features which are obtained from the device for the accurate diagnosis. In this study, we attempt to evaluate the repeatability of facial feature variables using the Sasang Constitutional Analysis Tool(SCAT) for the Sasang Constitutional face diagnosis. Methods Facial pictures of two subjects were taken 24 times respectively for two days according to a standard guideline. In order to evaluate the repeatability, the coefficient of variation was calculated for the facial features extracted from frontal and profile images. Results The coefficient of variation was less than 10% in most of the facial features except the upper lip, trichion, and chins related features. Conclusions It was confirmed that the coefficient of variation was small in most of the features which enables the objective and reliable analysis of face. However, some features showed the low reliability because the location of facial landmarks related to them is ambiguous. In order to solve the problem, a clear basis for the location discussion is required.