• 대한안전경영과학회지
• /
• 제11권3호
• /
• pp.209-216
• /
• 2009

A development in method of evaluating the measurement precisions using approximate F tests and variance components from expected mean square (EMS) is investigated. The research proposes three-factor mixed measurement models with the fixed and random factors. Unrestricted and unconstrained design work was rarely studied, while restricted and constrained designs have been significantly discussed. The unrestricted and unconstrained designs assume to be an independence of interaction. The proposed evaluation method about the measurement precisions can be extended to four-factor random measurement model or mixed measurement model. The study also presents the three evaluation indexes of precisions such as R&RTR (Reproducibility & Repeatability-To-Total Precision Ratio), PTR (Precision-To-Tolerance Ratio), and SNR (Signal-To-Noise Ratio). Numerical examples are proposed to evaluate the approximate F tests with Satterthwaite degrees of freedom and three indexes using the measurement precisions from EMS.

• 한국품질경영학회:학술대회논문집
• /
• 한국품질경영학회 1998년도 The 12th Asia Quality Management Symposium* Total Quality Management for Restoring Competitiveness
• /
• pp.361-377
• /
• 1998

The measurement of welding temperature of connector is usually performed with an infra red temperature gauge. However, the factors, which influence the temperature measurement, are rarely known. This research used the welding temperature measurement of the connector as an example, applying the experimental design, in two-phase experiments, to search the affecting factors. In phase-I experiment, we used a resolution III, seven-factor fractional factorial design with two levels for each factor. The result showed that none of the factor was significant in affecting the welding temperature when the type I error ${\alpha}$ was 0.05. Next, we did the phase-II factorial experiment with three factors and each factor had three levels. The experiment showed the experimental time was significant in affecting the temperature measurement when the type I error ${\alpha}$ was 0.05. Further Duncan's multiple range tests on the second experimental data showed that the later the experimental time, the weaker the light intensity could have on the temperature measurement and the average of the highest temperatures was lower. Moreover, the later the experimental time, the smaller was the variance of the temperature measurement and the difference between the averages of the highest and the lowest temperatures was also lower.

• 한국생산제조학회지
• /
• 제6권4호
• /
• pp.80-88
• /
• 1997

An experimental investigation of the fatigue through crack growth behavior under simple stepped variable loading condition has been performed using Al7075-T651. Experiments were carried out by using cantilever bending type specimens, with chevron notches on a small electro-magnetic test machine. Tensile overloads have a retarding effect on the fatigue crack growth rates, therefore tensile overloads were used for the beneficial effect on the fatigue life. While in most cases compressive overloads have only a vanishing effect on crack growth rates, some experiments with single edge crack tension specimens reveal a marked growth retardation. The stress ratios used in this investigations varies from R=0.32 to 0.81, from R=0.04 to 0.76, from R=-0.15 to 0.73, and from R=-0.33 to 0.68 and the peak load for each case was not varied. The crack growth and crack closure were measured by Kikukawa's compliance method with a strain gauge mounted on the backside of each specimens. The results obtained are as follows. When the stepped variable load was applied, the smaller the stress ration was, the larger the delayed retardation of the crack growth rate was. The fatigue crack growh rate data obtained for through cracks were plotted well against the effective stress intensity factor range from 4.0 to 20.0MP{a^{SQRT}m}. It was found that the effective stress intensity factor range ratio was related well to the opening stress intensity factor, the maximum stress intensity factor, and crack length.

• 감성과학
• /
• 제24권4호
• /
• pp.117-128
• /
• 2021

본 연구의 목적은 마우스 사용 시 손목터널증후군을 예방할 수 있는 스마트장갑을 연구하는 것이다. 연구에 앞서 손목의 좌·우 움직임은 미세하므로 게이지율(Gauge Factor)이 크고, 이력현상(Hysteresis)이 적은 인장 직물 센서가 필요하다. 만능재료시험기(UTM)를 통해 4가지의 직물을 분석하여 각각의 게이지율을 계산하고, 이력현상도 가장 적은 직물을 선택하였다. 또한, 3가지 부착방법을 아두이노로 분석하여 센서값 변화(△Sensor Value) 값이 큰 방법을 선택하였다. 선택된 직물과 부착방법으로 제작한 프로토타입을 아두이노를 통해 데이터 패턴을 분석하였다. 첫 번째는 센서 1개(A 센서)로만 파악하는 방법이고, 두 번째로는 센서 2개(A, B 센서)로 파악하는 방법이다. 손목 왼쪽(A 센서), 손목 오른쪽(B 센서) 양쪽에 인장 직물 센서를 부착하고, 손목을 오른쪽으로 꺾을 때 A 센서는 늘어나서 △Sensor Value 값이 커지고, B 센서는 줄어들어서 △Sensor Value가 작아진다. 반면에 손목을 왼쪽으로 꺾을 때는 반대로 패턴이 분석되었다. 본 연구를 통해 손목이 꺾일 시 LED가 켜지는 알고리즘으로 손목터널증후군을 예방하는 스마트장갑을 연구하였고, 본 연구 결과를 기반으로 후속 연구에서는 10명을 대상으로 직접 마우스를 사용하면서 실제 사용 시 문제점을 파악하고 파악된 문제점을 해결하고자 한다.

• 한국의류학회지
• /
• 제35권11호
• /
• pp.1362-1376
• /
• 2011

This study examines the effect of the structural properties of F/W wool knit fabrics for woman's knitwear on the perceptions of textures and sensible images of consumers and present basic data for textile designing by analyzing the relationship among the structural properties, mechanical properties, objective hand measurements and preferences. A total of 12 kinds of knit fabrics were prepared and investigated in terms of the differences in the subjective, mechanical properties and objective hand measurements according to the structural properties of knit fabrics. The data were analyzed by t-test. The subjective hand attributes of wool knits through factor analysis are categorized into 6 factors. In particular, the 'active/comfort' factor is a meaningful result that reflects the unique characteristics of knit fabrics compared to woven fabrics. Mechanical properties and objective hand measurements have a greater effect on textures than on sensible images; in addition, the structural properties, 'gauge' was the most important factor to influence the subjective evaluation.

• 한국정밀공학회지
• /
• 제14권11호
• /
• pp.126-134
• /
• 1997

In this study, We made visual inspection system using Vision Board. It is consist of an illuminator (a fluorescent lamp), image input device (CCD (Charge-Coupled Device) camera), image processing system(Vision Board(FARAMVB-02)), image output device (video monitor, printer), and a measuring instrument(TELMN1000). Length measurement by visual inspection system make use of 100mm guage block(instead of calculating distance between a camera and a object). It measured horizontal and vertical length factor from 400mm to 650mm by increasing 50mm. In this place, measured horizontal and vertical length factor made use of length measure- ment of a injection. A measuring instrument used to ompare a measured length of a injection visual inspection system with it. In conclusion, length measurement of a injection compared a measuring instrument with visual inspecion system using length factor of 100mm gauge block. We find that maximum error of length is 0.55mm when it compar with the measuring value of two devices(FARAMVB-02, TELMN1000). Program of visual inspection system is made up Borland C++3.1.

• 한국수자원학회:학술대회논문집
• /
• 한국수자원학회 2006년도 학술발표회 논문집
• /
• pp.643-646
• /
• 2006

An operational calibration is applied to improve radar rainfall intensity using rainfall obtained from rain gauge. The method is applied under the assumption of the temporal continuity of rainfall, the rainfall intensity from rain gauge is linearly related to that from radar. The method is applied to the cases of typhoon and rain band using the reflectivity of CAPPI at 1.5km obtained from Jindo radar. The CAPPI is obtained by bilinear interpolation. For the two cases, the rainfall intensities obtained by operational calibration are very consistent with the ones by the rain gauges. The present study shows that the correlation between the rainfall intensity by operational calibration and rain gauges is better than the one between the rainfall intensity by M-P relationship and rain gauges. The correlation coefficients between the total rainfall intensity obtained by operational calibration and rain gauges in typhoon and rain band cases are 0.99 and 0.97, respectively. Areal rainfalls are estimated using the field of calibration factor interpolated by Barnes objective analysis. The method applied here shows an improvement in the areal rainfall estimation. For the cases of typhoon and rain band, the correlation between the areal rainfall by operational calibration and rain gauges is better than the one between the area rainfall by M-P relationship and rain gauges. The correlation coefficients between the areal rainfall obtained by operational calibration and rain gauges in typhoon and rain band cases are 0.97 and 0.84, respectively. The present study suggests that the operational calibration is very useful for the real-time estimation of rainfall intensity and areal rainfall.

• 한국산학기술학회논문지
• /
• 제15권11호
• /
• pp.6399-6405
• /
• 2014

오늘날 작업능률 및 운용효율의 향상을 위해 장비의 대형화 추세가 진행되고 있으나 이와 더불어 사고 발생 시에는 많은 인명 피해와 함께 크나큰 경제적인 손실을 초래하게 되어 대형장비의 안전성 문제에 대하여 많은 연구가 진행되고 있다. 대형구조물의 안전성 감시를 위해 외부의 부하에 따른 구조물의 변형은 스트레인게이지로, 순간적인 충격에 의한 진동은 가속도 센서를 이용한다. 본 연구에서는 고분자 압전 필름센서인 PVDF(PolyVinyliDene Fluoride)를 이용하여 구조물의 변형에 대한 측정뿐만 아니라 충격에 대해서도 민감하게 반응하여 하나의 센서로 부하와 충격을 모두 검출하여 산업적 효율성과 실효성 향상을 도모하였다. 개발된 센서는 스트레인 게이지의 출력값에 대해 14% 이내의 오차를 나타내고 가속도 센서와는 충격에 대해 동일한 패턴의 충격신호를 나타내었다.

• 대한한의학회지
• /
• 제16권2호
• /
• pp.225-247
• /
• 1995

Using Bi-Digital O-Ring Test which was developed by Ohmura Toshiaki, constiution classification by the vegetables' was Measured by various muscle power measurement meters and the results are as follow: 1. Pinch Gauge (Model:pc5030HPG, Japan) is the gauge to measure finger power between the thumb and the second finger, Grip Strength Dynamometer (Model: T.K.K. 5101, Japan) is to measure the hand power (hand dynamometer), Back Strength Dynamometer (Model: T.K.K. 5102, Japan) is to measure back muscle strength, Vertical jump Meter (Model: T.K.K. 5106, Japan) is to measure the height of jump. The above gauges were and its result found that the radish, potato, carrot and cucumber can influence to muscle strength was not true. 2. When the physical constitution is distinguished by the O-Ring Test method, Taeyangin's rate appeared as average 21% although it was insisted that there will be only 0.03-0.1%. This means that the physical constitution but it appears accidently according to the examinee's emotion about the material such as vegetable etc. as favor or unfavor. 3. It was found that the result of O-Ring Test is the same at any time and at any place was not true. there is no reemergence character. 4. The import of O-Ring Test mehtod to the physical discrimination disregarded that the mental factor influences absolutely to the physical heath in the ideological physi cal constitution medical science. 5. 'O-Ring Test method is a objective judgement method.' is wrong judgement. As you see on the above result, Bi-Digital O-Ring Test set the changeable voluntary muscle as the standard of the judgument, that was first mistake logically, second in spite of leass influence of mental influence by the examiner and examinee than the vegetable discrimination influence, the test disregarded the influence. Third, only grasp of some material on hand can influence to the voluntary muscle was a wrong theory disregarding the physiology. Finally the misunderstaning his subjective view as an objective view in spite of examiner and examinee's strong influence. Therefore such kind of physical descrimination method must be sublated.

• 센서학회지
• /
• 제12권5호
• /
• pp.199-204
• /
• 2003

본 논문에서는 Ta-N 스트레인게이지를 이용한 극한 환경용 세라믹 박막형 압력센서의 제작 및 특성에 관하여 연구하였다. 압력감지부로 Ta-N 스트레인게이지를 사용하였으며, SDB(Si-wafer Direct Bonding)와 전기화학적 식각정지법을 이용하여 매몰 cavity를 가지는 저가격 고수율의 Si 박막 다이어프램을 제작하였다. 또한, 실리콘 박막 다이어프램상에 박막형 스트레인게이지를 형성하여 세라믹 박막형 압력센서를 제작하였다. 제작된 세라믹 박막형 압력 센서는 기존의 스트레인 게이지를 이용한 로드셀에 비해서 온도특성이 우수하고 재현성, 소형화, 집적화 및 저가격화가 가능하기 때문에 고온, 고압 등의 각한 환경에서도 사용이 가능할 것으로 기대된다.