ANALYSIS OF BODY MEASUREMENT ERROR ABOUT 3D SCAN DATA FOR ELDERLY

Jinhee Park,Juwon Chung,Yu Hwa Hong,Yun Ja Nam 글로벌지식마케팅경영학회 2015 Global Fashion Management Conference Vol.2015 No.06

Measuring body size with a 3D scanner can reduce inter-measurer variability and provide better accuracy compared to using a traditional methods of measurement (Park, Nam, & Park, 2009). Many size measurement projects (or studies) that measure body size established a size measurement method prior to the development of a 3D scanner and automatic size measurement programs that produce 3D virtual body size measurements (Park, &Nam, 2012). Size data measured through an automatic size measurement program are more accurate and have a lower variability that is more appropriate for body measurements (Han, & Nam, 2004; Nam, Choi, Jung, & Yun, 2004). However, this method is limited to healthy subjects who can maintain a correct posture in a 3D scanner. It is difficult for the elderly to maintain the correct posture for body measurements in ‘Basic Human Body Measurements for Technological Design’ of ISO 7250(1997). Body measurement definitions are based on vertical and horizontal directions consequently, it is hard to measure those with a bent body type even if they stand in a correct posture. Most body measurement items are automatically measured in vertical and horizontal directions because current automatic size measurement programs utilize algorithms based on typical body measurement definitions. The size measurement method based on a vertical and horizontal directions tends to have a problem for elderly individuals with a bent body type who have difficulty maintaining a correct posture for 3D scanning as defined in ISO 7250(1997)(Ashdown, & Na, 2008).This study analyzes the problem of present auto-measurement programs that use elderly’s 3D body scan data. We conducted a comparative analysis of elderly’s body sizes using an auto-measurement program from virtual 3D body scan data and direct measurement with traditional measurement methods. We establish 34 typical body size measurements for the use of data from 464 males and 472 females (total 936) between the ages of 70 to 85. For error analysis, data separated to normal values and outliers compared with ISO 20655(2003). ISO 20685 defines the accuracy of extracted measurements by classification and measurement type (segment lengths, body height/breaths/depth, large/small circumferences, and head/hand/foot dimensions). The majority of outliers for the male and female body height type was “height”. Total number of persons with outliers for Height’s data was 603; consequently, 64.4% of subjects (elderly group of 70-85 yrs.) could not maintain a correct posture when scanning. Other data also had many errors from inaccurate measurement postures. A total of 72.3% of males and 70% of females have incorrect values in small circumferences. The segment lengths’ error data was 76.5% of males and 75% of females; in addition, the head dimension’ outliers were 87% for both male and female subjects. Especially 57.46% of males had incorrect data, while 74.67% of females had a type of large circumference. Female chest circumference had significant errors due to sagging breasts. The differences identify with a correlation between type of large circumference (chest, hip, under bust, waist, waist of omphalion) and gender. There were several correlations between the many measurement errors because values over 70% of data have outliers; however, each measurement type has properties in regards to correlation. A substantial positive correlation was found between all measurements (except hip circumference) in the type of large circumference; in addition, one-way ANOVA indicated that the measurements influenced height and were statistically significant. Outliers found in height data for the elderly’s were more likely to have errors in the type of large circumference. The type of body height indicated a strong correlation and statistical significance between the axilla height and other measurements (height, waist, crotch, lateral malleolus). Axilla height with more outliers indicated that other type of body height measurements had a higher potential for errors. The posture for body measurement was standardized as standing erect; however, this study indicated that many measurement errors were possible between using an auto-measurement program and direct measurement. The value of outlier about a particular measurement item can expect increased errors about any group (height: large circumference group/ axilla height: body height group). We have to study the relation in measurements in these types ‘large circumference’ because ‘head dimensions’ types correlate between measurements in each group. We need a more detailed analysis about outliers to find the major factors for measurement errors in regards to the elderly as well as discuss the possibility of ISO measurement-standard’s application for the elderly.

Bias-Compensated Pseudo-measurement Tracking Filter Design in Line-of-Sight Coordinates

조민현,탁민제,박준현 한국항공우주학회 2021 International Journal of Aeronautical and Space Sc Vol.22 No.2

Target tracking using pseudo-measurement is widely used because of its simple implementation and computational advantages despite biased behavior. The biasedness of the pseudo-measurement tracking filter originates from a measurement-dependent Kalman gain and a state-dependent non-Gaussian biased noise. This paper proposes a bias-compensated pseudo-measurement filter considering a range rate measurement in the line-of-sight Cartesian coordinate system. Firstly, a pseudo-measurement model incorporating range rate measurements in line-of-sight coordinates is derived. The noise and measurement covariance of a proposed de-biased pseudo-measurement model are shown to be statistically consistent for highly noisy measurements. Secondly, a bias-compensated pseudo-measurement filter that adopts modified gain to suppress the estimation bias is formulated. The asymptotic stability of a proposed filter is further discussed. Lastly, simulation results show that a proposed de-biased pseudo-measurement filter is very effective in considering a range rate measurement.

우리나라와 일본의 초등학교 수학과 교육과정 측정 영역 비교・분석: 외연량을 중심으로

박교식 한국학교수학회 2018 韓國學校數學會論文集 Vol.21 No.1

본 연구에서는 우리나라의 2015 개정 초등학교 수학과 교육과정과 일본의 2017 개정 초등학교 수학과 교육과정 <측정 영역>의 7개 외연량 시간, 길이, 들이, 무게, 넓이, 각도, 부피의 지도 실정을 비교, 측정, 어림재기의 관점에서 비교・분석하고 있다. 이러한 비교・분석의 결과로부터 우리나라의 차기 초등학교 수학 교과서 및 차기 초등학교 수학과 교육과정 개발과 관련하여 다음과 같은 논의가 필요하다는 것을 제안할 수 있다. 첫째, 시간, 길이, 들이, 무게, 넓이, 각도, 부피 각각에 대해 비교(직관적 비교, 직접 비교. 간접 비교), 직접 측정(임의 단위에 의한 측정, 표준 단위에 의한 측정), 간접 측정, 어림재기의 취급 범위를 명확히 하는 것에 대한 논의가 필요하다. 둘째, 직관적 비교가 곤란한 경우에 직접 비교를 하게 하는 것에 대한 논의가 필요하다. 셋째, 무게의 간접 비교를 재고하는 것에 대한 논의가 필요하다. 넷째, 임의 단위에 의한 각도의 측정을 재고하는 것에 대한 논의가 필요하다. 다섯째, 넓이 1 ㎠와 1 ㎡ 및 부피 1 ㎤와 1 ㎥가 각각 어느 정도의 크기인지를 짐작할 수 있게 하는 B류 어림재기를 취급하는 것에 대한 논의가 필요하다. In this study, the actual state of teaching seven extensive quantities (time, length, capacity, weight, area, angle measure, volume) of measurement domain are analyzed comparatively between the 2015 revised elementary school mathematics curriculum in Korea and the 2017 revised elementary school mathematics curriculum in Japan in terms of comparison in measurement, direct measurement, indirect measurement, and estimation in measurement. From the results of this comparative analysis, some implications for discussion on the development of the next elementary school mathematics textbook and the next elementary mathematics curriculum can be suggested. First, it is necessary to discuss on clarifying the range of handling of comparison, direct measurement, indirect measurement, estimation of seven extensive quantities respectively. Second, it is necessary to discuss on doing direct comparison when intuitive comparison is difficult. Third, it is necessary to discuss on reconsidering indirect comparison of weights. Fourth, it is necessary to discuss on reconsidering measurement using arbitrary units in case of angular measures. Fifth, it is necessary to discuss on dealing with estimating the area of 1 ㎠ and 1 ㎡ and the volume of 1 ㎤ and 1 ㎥ for the purpose to make rough guesses their size respectively.

스포츠 현장 활용을 위한 신체활동량의 측정과 추정 방법 분류

이병근(Byung Kun Lee) 상명대학교 공학기술연구소 2003 공학기술연구 Vol.2003 No.1

The purpose of this study is to analyze the principles, characteristics, and application methods of the measurement and estimation methods of physical activity, and to classify the variety methods for application on sports fields. The measurement and estimation of energy expenditure during physical activity is important for health improvements, fitness training, and preventing disease. The physical activity is measured by direct measurement, indirect measurement, and estimation. The principle' of direct measurement is the law of energy preservation, and the Bomb calorimeter is its measurement equipment. Direct measurement has many limitations, Therefore, indirect measurement by oxygen consumption is usually used. Indirect measurement methods of energy expenditure include the Douglas bag, Autonomic and Portable metabolic analysis system. The Douglas bag is used to collect expired gas. Autonomic metabolic analysis system can measure variables such as oxygen consumption, ventilation, respiratory exchange ratio, simultaneously by connection with the computer. Portable metabolic analysis system was developed to measure energy expenditure during activity of out-field. The energy expenditure by direct method can be measured exactly by the development of measurement equipment and supporting devices. However, it has several limitations such as cost, efforts of subjects, and efforts of researchers for mass group measurements. Therefore, the estimation method was developed for convenience, even the validity was decreased, The estimation methods include motion sensor, measurement of physiological responses, observation and Time/Motion analyses, activity diary method, and physical activities questionnaire, etc. There were a lot of methods used for the measurement and estimation of energy expenditure. These methods used by demands of exactness, convenience, cost, time, etc.

연구활동종사자 작업환경측정 결과 및 제도개선 방향

황제규 ( Je-gyu Hwang ),변헌수 ( Hun-soo Byun ) 한국산업보건학회 (구 한국산업위생학회) 2020 한국산업보건학회지 Vol.30 No.4

Objectives: The characteristics of research workers are different from those working in the manufacturing industry. Furthermore, the reagents used change according to the research due to the characteristics of the laboratory, and the amounts used vary. In addition, since the working time changes almost every day, it is difficult to adjust the time according to exposure standards. There are also difficulties in setting standards as in the manufacturing industry since laboratory environments and the types of experiments performed are all different. For these reasons, the measurement of the working environment of research workers is not realistically carried out within the legal framework, there is a concern that the accuracy of measurement results may be degraded, and there are difficulties in securing data. The exposure evaluation based on an eight-hour time-weighted average used for measuring the working environment to be studied in this study may not be appropriate, but it was judged and consequently applied as the most suitable method among the recognized test methods. Methods: The investigation of the use of chemical substances in the research laboratory, which is the subject of this study, was conducted in the order of carrying out work environment measurement, sample analysis, and result analysis. In the case of the use of chemical substances, after organizing the substances to be measured in the working environment, the research workers were asked to write down the status, frequency, and period of use. Work environment measurement and sample analysis were conducted by a recognized test method, and the results were compared with the exposure standards (TWA: time weighted average value) for chemical substances and physical factors. Results: For the substances subject to work environment measurement, the department of chemical engineering was the most exposed, followed by the department of chemistry. This can lead to exposure to a variety of chemicals in departmental laboratories that primarily deal with chemicals, including acetone, hydrogen peroxide, nitric acid, sodium hydroxide, and normal hexane. Hydrogen chloride was measured higher than the average level of domestic work environment measurements. This can suggest that researchers in research activities should also be managed within the work environment measurement system. As a result of a comparison between the professional science and technology service industry and the education service industry, which are the most similar business types to university research laboratories among the domestic work environment measurements provided by the Korea Safety and Health Agency, acetone, dichloromethane, hydrogen peroxide, sodium hydroxide, nitric acid, normal hexane, and hydrogen chloride are items that appear higher than the average level. This can also be expressed as a basis for supporting management within the work environment measurement system. Conclusions: In the case of research activity workers' work environment measurement and management, specific details can be presented as follows. When changing projects and research, work environment measurement is carried out, and work environment measurement targets and methods are determined by the measurement and analysis method determined by the Ministry of Employment and Labor. The measurement results and exposure standards apply exposure standards for chemical substances and physical factors by the Ministry of Employment and Labor. Implementation costs include safety management expenses and submission of improvement plans when exposure standards are exceeded. The results of this study were presented only for the measurement of the working environment among the minimum health management measures for research workers, but it is necessary to prepare a system to improve the level of safety and health.

디지털 영상 계측 기술의 영향인자에 따른 정밀도 분석

김광염,김창용,이승도,이정인 한국지반공학회 2007 한국지반공학회논문집 Vol.23 No.12

This study has reviewed the applicability of displacement measurement by using a digital vision technique based on typical photogrammetric methods. In this study, a series of experimental measurements have been performed in order to improve the accuracy of digital vision measurement by establishing criteria of factors of various vision measurements. It is found that the digital vision measurement tends to show higher accuracy as the image size (resolution) and the focal length become larger and the distance to an object becomes closer. It is also observed that measurement error decreases with processing as many images as possible in various angles. Applicability on high-resolution displacement measurement is proved by applying the digital vision measurement developed in this study to a large scale loading test of concrete lining.

대학생의 교육만족도 측정도구 개발 연구 : A지역의 S대학을 중심으로

신혜종(Shin Heajong),김미량(Kim Milyang),유영의(You Yungeui) 학습자중심교과교육학회 2020 학습자중심교과교육연구 Vol.20 No.21

In order for a measurement of education satisfaction to be an effective tool in the quality control mechanism, the measurement should be reliable and valid. The purpose of this study was to develop and validate a measurement tool of collegiate education satisfaction that is based on S university’s ideology of education. The study was consist of two phases. In the first phase, the constructs of education satisfaction specifically for S university were sought and 6 categories are derived. In the second phase, education satisfaction measurement were developed and standardization of the measurement were conducted. Based on the literature review and study of prior measurement tools used in universities, a preliminary measurement that has 6 sub-scales with 180 items was developed. That measurement went through two steps of face validity test. As a result, a 60-item(10 items in each sub-scale) collegiate education satisfaction measurement was drawn. In the second phase, a series of tests were conducted in order to establish the measurement’s reliability and validity. 200 students who were enrolled in S university at the time of the study have participated in the process. For the reliability, the internal consistency of the whole and each sub-scales were conducted. For the validity, the correlation of the measurement with related constructs such as ‘university’s potential’, ‘university preference’, and ‘overall satisfaction’ were conducted. The result showed that the measurement has high internal consistency in all of 6 sub-scales and high correlation with criterion-related constructs. 교육만족도조사 결과가 대학교육의 질 관리 기제로서의 역할을 제대로 수행하기 위해서는 개별 대학의 특성을 반영하면서, 신뢰도과 타당도를 확보한 측정도구가 필요하다. 본 연구의 목적은 A지역에 소재한 S대학교의 교육이념과 학교특성을 반영한 교육만족도 측정도구를 개발하고, 그에 대한 신뢰도와 타당도를 점검하는 것이다. 연구목적을 달성하기 위해 선행연구 분석을 기반으로 교육만족도를 구성하는 6개의 하위요인을 도출하였고, 각 요인별로 30개의 예비문항을 구성하였다. 예비문항에 대하여 2 단계에 걸친 안면타당도 검증 과정을 실시하였다. 1차로 교육만족도 평가도구 개발연구위원회의 위원을 대상으로 실시하여 6개 요인에 대해 총 60문항으로 재구성하였고, 이 척도에 대해 단과대 학장들과 전체 학과장을 대상으로 2차 안면타당도 검증을 수행하였다. 검증된 척도는 S대학교 재학생 200명을 대상으로 표준화 연구를 진행하였다. 신뢰도는 내적일치도를, 타당도는 준거 관련 타당도를 통해 검증하였는데, 그 결과 S대학교의 교육만족도 진단도구는 각 하위 요인의 내적일치도가 높고, 진단도구의 모든 하위요인과 ‘학교발전가능성’, ‘학교선호도’, ‘전반적 교육 만족도’ 등의 준거문항 간에 상관관계가 높은 것으로 나타나, 신뢰도와 타당도를 확보했다고 볼 수 있다.

밀리미터파(W대역) 안테나 측정을 위한 원-전계 측정 시스템 설계 및 검증

백종균,황인준,조치현,주정명,주지한,박종국,김재식,김소수 한국인터넷방송통신학회 2022 한국인터넷방송통신학회 논문지 Vol.22 No.2

In this paper, we designed and verified a Far-field measurement system for measuring the performance of an antenna operating in millimeter wave(W-band). For the antenna test, a measurement system should be selected according to the type of antenna, measurement items, measurement environment and period, etc. In the case of near-field measurement, it takes a lot of time because the number of measurement items increases when the antenna has multiple channels or various beams. Such an antenna can reduce the measurement time through Far-field measurement, and only necessary measurement items can be measured. Therefore, this study secured precise alignment of the far-field measurement system using a high-power laser and improved the measurement accuracy by applying a double amplifier system. The designed system was built in the anechoic chamber and verified by comparison with the verified Near-field measurement system. 본 논문에서는 밀리미터파 W대역에서 동작하는 안테나 성능 측정을 위한 원-전계 측정 시스템을 설계하고 검증하였다. 안테나 성능 시험은 안테나의 종류, 측정 항목, 측정 환경 및 기간 등에 따라 측정 시스템을 선택해야 한다. 근접 전계 측정은 안테나가 다중 채널을 가지거나 다양한 빔을 가지고 있을 경우, 측정 항목이 증가하기 때문에 많은시간이 소요된다. 이러한 안테나는 원-전계 측정을 통해 측정 시간을 단축 할 수 있고 필요한 측정 항목만 측정이 가능하다. 따라서 본 연구는 원-전계 측정 시스템을 고출력 레이저를 이용하여 정밀한 정렬을 확보하고 이중 증폭기 시스템을적용하여 측정 정확도를 향상하였다. 설계된 시스템은 무반향 챔버 내 구축하였으며 검증된 근접 전계 측정 시스템과비교하여 검증하였다.

호텔업에서 성과측정의 다양성과 성과측정 시스템 만족도의 관련성

최해수,유승억 한국호텔외식관광경영학회 2007 호텔경영학연구 Vol.16 No.2

많은 기업들은 기업의 목표달성을 위한 높은 잠재력을 제공하는 전략을 식별할 수 있는 정보를 제공하는 성과 측정 시스템을 도입하고 있다. 이러한 전략적 성과 측정시스템 에 대한 접근법 중의 하나는 단기 재무척도에서는 정확히 반영되지 않는 주요 전략적 성과 범주를 포착할 수 있는 다양한 비재무 척도가 전통적 재무적 척도를 보완할 수 있다는 것이다. 본 연구에서는 70개 호텔에 대한 설문 자료를 이용하여 재무적 성과 측정과 비재무적 성과 측정의 중요성에 대해서 조사하고, 측정의 다양성과 측정 시스템에 대한 만족도간의 관련성을 검증하였다. 성과척도의 이용 현황에 대한 조사결과에 의하면 우리나라 호텔들은 전반적으로 재무적 척도뿐만 아니라 다양한 범주의 비재무 척도를 이용하고 있는 것으로 나타났으며, 특히 단기 재무성과, 고객관계, 서비스/ 상품의 품질과 관련한 성과 척도가 중요하게 고려되고, 이용되는 것으로 나타났다. 가설 검증결과에 의하면 측정의 다양성은 측정시스템과 유의적인 정(+)의 관련성이 있는 것으로 나타났다. 측정의 다양성을 재무적 성과 척도의 이용과 비재무적 성과 척도의 이용으로 세분하여 측정 시스템 만족도와 회귀 분석한 결과에 의하면 재무적 척도의 이용과 비재무적 척도의 이용 모두 측정 시스템의 만족도에 유의적인 정(+)의 영향을 미치는 것으로 나타났다. Many firms are adopting strategic performance measurement systems that provide information that allows the firm to identify the strategies offering the highest potential for achieving the firm's objectives. One approach to strategic performance measurement is supplementing traditional financial measures with a diverse mix of non-financial measures that are expected to capture key strategic performance dimensions that are not accurately reflected in short-term accounting measures.Using data from 70 hotels, this study examines the association between measurement diversity and measurement system satisfaction. We also examine the importance of financial and non-financial measurement.We find evidence that hotels making more extensive use of a broad set of financial and non-financial measures have higher measurement system satisfaction. Our results also suggest that both the use of financial measures and the use of non-financial measures are significantly associated with measurement system satisfaction respectively. Our results may not generalize to other industries, future studies can extend our analysis.

초등학교에서의 넓이 측정 지도에 관한 고찰 -2007년 개정 수학과 교육과정을 중심으로

오영열 ( Young Youl Oh ) 서울敎育大學校 初等敎育硏究所 2011 한국초등교육 Vol.21 No.1

본 연구는 초등학교 수학과 측정 영역 가운데서 넓이 측정에 대해 학문적 연구 결과 드러난 사실들을 바탕으로 2007년 개정 수학과 교육과정 및 이에 근거한 수학 교과서에 나타난 넓이 측정 내용을 고찰 및 분석하는데 그 주요한 목적이 있다. 본 연구 결과를 바탕으로 드러난 점들을 요약하면 다음과 같다. 첫째, 넓이 측정에 대한 지도는 절차적 지식 중심이 아니라 측정을 이해하는데 중요한 아이디어에 초점을 맞추는 개념적 접근이 이루어져야 한다. 이를 위해서 넓이 측정의 개념적 토대가 되는 측정 단위에 대한 의미를 이해하는 것이 중요하다는 것을 지적한다. 둘째, 2차원적인 평면 도형의 넓이를 측정하는 원리를 이해하기 위해서는 단위 정사각형으로 직사각형을 완전히 덮고 그 개수를 세는 것이 아니라 단위 정사각형이 직사각형 내에서 어떠한 형태로 배열이 되는지에 대한 직사각형의 배열 구조를 학생들이 이해할 수 있도록 지도할 필요가 있다. 셋째, 우리나라 수학 교과서에 대한 고찰 결과 1학년의 비교하기 활동이 4학년에서의 보편단위를 도입한 직사각형의 넓이 측정으로 유기적인 연결이 부족하며, 이를 보완하기 위해서 임의단위로서 구체물을 활용하여 넓이를 측정해 보는 기회가 필요하다. 측정을 배우는 것은 측정 과정에서 중요한 수학적 사고 과정을 배우는 것이다. 측정을 틀에 박힌 공식 암기에 의존하여 학습할 경우 측정 지식을 일반화하는데 어려움이 있으며, 따라서 측정에 대한 본질적인 아이디어를 배울 수 있도록 개념적 접근이 강화될 필요가 있다. 마지막으로 넓이 측정에 대한 학생들의 개념적 이해를 돕기 위해서는 교사들이 넓이 개념에 대해 충분한 이해가 선행되어야 할 것이다. The purpose of the present study is mainly to review the findings from the research of area measurement during the last two decades, to investigate the contents of area measurement in the revised 2007 national mathematics curriculum and mathematics textbooks, and finally to compare the results of the latter on the basis of the research findings. The results of this study are as follows: First, teaching about area measurement needs to be focused on ``important ideas`` to help students` understanding of fundamental concepts of area measurement rather than the procedural knowledge. Secondly, structuring an array is at the heart to understand two-dimensional area measurement. Thirdly, there was a lack of connection of teaching area measurement between intuitive comparison of objects in the first grade and the use of the standard unit to measure the two-dimensional rectangle. Thus, students need to have an opportunity to measure area of objects using concrete materials as informal units. To learn measurement is to investigate the process of the important mathematical ideas. Thus, the conceptual approach to measurement is the way to learn the fundamental ideas of measurement. In addition, teachers` deep understanding of the fundamental concepts of area measurement is necessary to help students understand the conceptual learning of area measurement.