• 제목/요약/키워드: Non-direct measurement

검색결과 127건 처리시간 0.029초

Body Measurements for Designing Hip Dislocation Prevention Garment in Children with Cerebral Palsy

  • Lee, Ah Lam;Han, Hyunjung
    • 한국의류학회지
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    • 제46권3호
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    • pp.454-463
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    • 2022
  • This study aims to provide basic size data for the development of a hip dislocation prevention garment for cerebral palsy (CP) children and useful information for the design of garment products for CP children through identifying differences in body shape between CP and non-CP children and reviewing the tibial-stature prediction formulas of previous studies. Forty-seven Korean children with CP aged 2 to 14 years were measured for body size from October 2019 to August 2020. Body measurements of 18 sites, including greater trochanter length, which is an important site for a hip dislocation prevention garment, were collected and analyzed. Data of non-CP children were taken from same age of Size Korea and compared. Tibial-stature prediction formulas suggested in four previous studies were also reviewed. CP children had significantly lower stature as well as circumferential dimensions when compared to non-CP children. Greater trochanter length is difficult to predict through other body dimensions. Thus, direct measurement is required. Of the general key dimensions used in the clothing industry, only hip circumference could explain the body shape of CP children. Tibial-stature prediction formulas cannot always but tend to largely predict the actual stature of CP children.

Modal parameter identification of civil structures using symplectic geometry mode decomposition

  • Feng Hu;Lunhai Zhi;Zhixiang Hu;Bo Chen
    • Wind and Structures
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    • 제36권1호
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    • pp.61-73
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    • 2023
  • In this article, a novel structural modal parameters identification methodology is developed to determine the natural frequencies and damping ratios of civil structures based on the symplectic geometry mode decomposition (SGMD) approach. The SGMD approach is a new decomposition algorithm that can decompose the complex response signals with better decomposition performance and robustness. The novel method firstly decomposes the measured structural vibration response signals into individual mode components using the SGMD approach. The natural excitation technique (NExT) method is then used to obtain the free vibration response of each individual mode component. Finally, modal natural frequencies and damping ratios are identified using the direct interpolating (DI) method and a curve fitting function. The effectiveness of the proposed method is demonstrated based on numerical simulation and field measurement. The structural modal parameters are identified utilizing the simulated non-stationary responses of a frame structure and the field measured non-stationary responses of a supertall building during a typhoon. The results demonstrate that the developed method can identify the natural frequencies and damping ratios of civil structures efficiently and accurately.

대형 Digital TV용 Display Unit의 강성 측정 (Elastic Modulus Measurement of a Large Size Digital TV Display Unit)

  • 김창희;문성인;최재붕;김영진;이정권;구자춘
    • 한국정밀공학회지
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    • 제22권3호
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    • pp.115-122
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    • 2005
  • As the digital TV markets rapidly growing, many manufacturers introduce large size flat screen TV units. There are two different display types available to large size models which are plasma and TFT-LCD. Since both are constructed with thin large panels that are mostly fragile to even moderate mechanical shock inputs. Some large size panels are severely resonated by the acoustic sound generated TV which deteriorates video quality. Recognizing the potential problems of large displays, accurate measurement of the panels is to be an essential task for the reliable design. Measurement of mechanical properties of a thin large crystallized panel such as TFT-LCD display with traditional material testing equipments is challenging. Since TFT-LCDs are constructed with combination of brittle glass panels, polymer sheets, and liquid crystal, their properties are not only anisotropic but also usually non-linear. Accurate measurement of the properties often requires very expensive facilities. Especially when the size of the test sample is as large as 40-inch or wider, direct measurement cost is prohibitive. Even worse, machining of the large TFT-LCD to make a smaller size specimen that could be fit into a material tester is not possible because of liquid crystal leakage. A new method fer the measurement of elastic modulus of large TFT-LCD panel is presented in this article. The suggested method provides a simple, economic, and user-friendly way fer measuring the elastic modulus of large panels with considerable level of accuracy.

함수율과 이방성을 고려한 석조문화유산의 초음파 측정방법 설정 (Establishment of Ultrasonic Measurement Method for Stone Cultural Heritage Considering Water Content and Anisotropy)

  • 조영훈;이찬희
    • 보존과학회지
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    • 제30권4호
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    • pp.467-480
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    • 2014
  • 이 연구에서는 암석의 함수율과 이방성에 따른 초음파속도 변화를 분석하여 석조문화유산에 적합한 측정방법을 설정하였다. 암석의 함수율과 포화도는 건조 초기에 급격한 변화를 보이다가 변화율이 서서히 줄어드는 지수함수 형태를 나타냈다. 그러나 초음파속도 및 변화율은 10시간의 자연건조 이후 거의 일정한 수치를 유지하였다. 따라서 수분에 포화된 석조문화유산은 기상환경 및 함수조건을 고려하여 약 10시간의 자연건조 후에 초음파 측정을 수행해야 한다. 이방성지수는 화강암과 석회암에서 가장 높은 수치를 보였으며, 간접전달방법이 직접전달방법에 비해 이방성에 둔감한 측정법으로 나타났다. 그러나 간접전달방법에 의한 이방성은 모든 암석에 미약하게나마 존재하므로 다양한 방향성을 고려한 초음파 측정이 요구된다. 이 연구결과는 석조문화유산의 암석학적 특성에 적합한 맞춤형 비파괴진단과 신뢰도 높은 정밀 평가에 크게 기여할 것으로 사료된다.

염소원자의 반응속도 연구 (A Direct Kinetic Study of Cl Atom Reactions)

  • 주광열
    • 대한화학회지
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    • 제23권6호
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    • pp.349-357
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    • 1979
  • Flow-discharge-원자흡수선 측정법으로 $Cl(^2P_{1/2})$ 원자의 존재를 확인하였고 $Cl(^2P_{3/2})$ 원자의 여러 물질과의 반응속도를 직접적으로 측정하였다. 본 실험에서 얻은 결과는 간접적인 방법으로 얻은 반응속도와 거의 같음을 보였다. $Cl(^2P_{3/2})$ 원자와 $Cl(^2P_{1/2})$ 원자는 거의 같은 반응성을 가지며, 이러한 반응의 유사성 때문에 Cl(2P1/2) 원자가 Cl원자의 반응속도에는 그다지 큰 영향을 주지 않음을 보인다.

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병원급식 식기세정작업 생산성에 영향을 미치는 요인 (A Study on Factors Affecting the Productivity of Dishwashing Work in Hospital Foodservice Systems)

  • 박정순;홍완수
    • 한국식생활문화학회지
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    • 제12권1호
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    • pp.71-78
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    • 1997
  • The productivity of a hospital foodservice system has a significant implication in hospital management as costs for labor and material increase, competitions among hospitals increase, and patients' expectations as to the quality of hospital services increase. The foodservice is characterized by its labor intensiveness. The objective of this study was to examine associations between operational and managerial factors and the productivity of dishwashing work in hospital foodservice systems. The labor productivity in 20 conventional food service systems was assessed and related to a number of influencing variables within the system. The productivity measurement was based upon the total dish equivalents as a ratio of the total direct and non-direct labor hours required to wash these dishes. 20 hospitals with more than 500 beds located in Seoul were surveyed to obtain data for study variables. Questionnaire and a survey form were mailed. Statistical methods used in this study were descriptive analysis and Pearson product moment correlation analysis. Hospital system characteristic which was found to correlate significantly with productivity was the ratio of dish loss. As this increased, the productivity level increased.

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통합적 행동의도모델 적용에 의한 국내 대학생 소비자의 해외 진 브랜드 구매의도 분석 (Korean College Students' Purchase Intention of Foreign Jeans Brands -Applying an Integrated Behavioral Intention Model-)

  • 강지혜;진병호
    • 한국의류학회지
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    • 제34권8호
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    • pp.1341-1351
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    • 2010
  • The Korean jean market has become increasingly competitive due to the increased imports of global brands. This study is to understand the purchase behaviors of Korean college students toward foreign brand jeans to help Korean jean brands enhance their competitive advantages over foreign brand jeans in the Korean market. Considering perceptions of Korean consumers toward foreign brands and traditional value changes, this study proposed a research model incorporating two extended behavioral intention (BI) models, Lee's modified BI model and Ajzen's theory of planned behavior. To test the research model, a total of 240 valid data sets were collected from college students in Busan, Korea. Structural and measurement models were estimated using LISREL 8.80. Because face saving failed to attain internal validity, the research model was revised to eliminate face saving. The findings indicated that perceived behavioral control had the strongest direct influence on purchase intentions of Korean college students for foreign brand jeans. Group conformity and subjective norm had non-significant direct impacts on purchase intention, whereas group conformity had an indirect impact on purchase intention through attitude. Based on the findings, theoretical and managerial implications were provided.

일회용 마스크에 장착을 위한 레이저 기반 그래핀 습도센서 제작에 관한 연구 (A Study on the Fabrication of Laser-Induced Graphene Humidity Sensor for Mounting on a Disposable Mask)

  • 이준욱;신윤지;양혜정;신보성
    • 한국산업융합학회 논문집
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    • 제23권4_2호
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    • pp.693-699
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    • 2020
  • 355nm UV pulse laser is irradiated on the surface of polyimide (PI) by LDW (Laser Direct Writing) method to produce a high sensitivity flexible humidity sensor using a simple one-step process. The LDW method continuously investigates 2-D CAD data using a galvano scanner and an F-lens. This method is non-contact, so it minimizes physical strain on the PI. Laser-induced graphene (LIG) produced by lasers has a high surface area due to its high flexibility and numerous pores and oxidizers compared to conductors. For this reason, it is highly useful as a flexible humidity sensor. The humidity sensor produced in this study was attached to the inside of a mask filter, which has become a hot topic recently, and its applicability was confirmed.The measurement of humidity measured the sensitivity, reactivity, stability and recovery behavior of the sensor by measuring changes in capacitance and resistance.

THE NONDESTRUCTIVE MEASUREMENT OF THE SOLUBLE SOLID AND ACID CONTENTS OF INTACT PEACH USING VIS/NIR TRANSMITTANCE SPECTRA

  • Hwang, I.G.;Noh, S.H.;Lee, H.Y.;Yang, S.B.
    • 한국농업기계학회:학술대회논문집
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    • 한국농업기계학회 2000년도 THE THIRD INTERNATIONAL CONFERENCE ON AGRICULTURAL MACHINERY ENGINEERING. V.II
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    • pp.210-218
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    • 2000
  • Since the SSC(soluble solid contents) and titratable acidity of fruit are highly concerned to the taste, the need for measuring them by non-destructive technology such as NIR(Visual and Near-infrared) spectroscopy is increasing. Specially, in order to grade the quality of each fruit with a sorter at sorting and packing facilities, technologies for online measurement satisfying the tolerance in terms of accuracy and speed should be developed. Many researches have been done to develop devices to measure the internal qualities of fruit such as SSC, titratable acidity, firmness, etc. with the VIS(Visual)/NIR(Near Infrared) reflectance spectra. The distributions of the SSC, titratable acidity, firmness, etc. are different with respect to the position and depth of fruit, and generally the VIS/NIR light can interact with fruit in a few millimeters of pathlength, and it is very difficult to measure the qualities of inner flesh of fruit. Therefore, to measure the average concentrations of each quality factor such as SSC and titratable acidity with the reflectance-type NIR devices, the spectra of fruit at several positions should be measured. Recently, the interest about the transmittance-type VIS/NIR devices is increasing. NIR light can penetrate through the fruit about 1/10-1/1,000,000 %. Therefore, very intensive light source and very sensitive sensor should be adopted to measure the transmitted light spectra of intact fruit. The ultimate purpose of this study was to develop a device to measure the transmitted light spectra of intact fruit such as apple, pear, peach, etc. With the transmittance-type VIS/NIR device, the feasibility of measurement of the SSC and titratable acidity in intact fruit cultivated in Korea was tested. The results are summarized as follows; A simple measurement device which can measure the transmitted light spectra of intact fruit was constructed with sample holder, two 500W-tungsten halogen lamps, a real-time spectrometer having a very sensitive CCD array sensor and optical fiber probe. With the device, it was possible to measure the transmitted light spectra of intact fruit such as apple, pear and peach. Main factors affecting the intensity of transmitted light spectra were the size of sample, the radiation intensity of light source and the integration time of the detector. Sample holder should be designed so that direct light leakage to the probe could be protected. Preprocessing method to the raw spectrum data significantly influenced the performance of the nondestructive measurement of SSC and titratable acidity of intact fruit. Representative results of PLS models in predicting the SSC of peach were SEP of 0.558 Brix% and R2 of 0.819, and those in predicting titratable acidity were SEP of 0.056% and R2 of 0.655.

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알루미늄 분말 점화용 고밀도 스팀 플라즈마 제트 온도장 및 방출 스펙트럼 측정 (Temperature Field and Emission Spectrum Measurement of High Energy Density Steam Plasma Jet for Aluminum Powder Ignition)

  • 이상협;임지환;이도형;윤웅섭
    • 한국추진공학회지
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    • 제18권1호
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    • pp.26-32
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    • 2014
  • 본 연구에서 고에너지 금속 알루미늄의 효과적인 점화를 위해 개발한 직류 방식의 스팀 플라즈마 점화기 가스온도를 OH radical의 방출 스펙트럼을 사용하여 측정하였다. 플라즈마 제트온도는 초고온이므로 비접촉식 광학 계측 방법인 볼츠만 기울기법과 스펙트럼 비교 분석법을 이용하여 측정하였으며 각각의 방법은 정밀하게 검증 후 실험에 적용되었다. 플라즈마 점화기의 노즐 팁으로부터 30 mm 범위에서의 제트온도 측정결과 두 방법 모두 알루미늄의 점화온도(${\approx}2400K$) 이상의 2900 K ~ 5800 K를 확인할 수 있었다.