• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.25 no.2
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• pp.43-52
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• 2011

LED lighting may cause different sensation and color appearance due to the different spectral power distributions compared to those of conventional lightings. Particularly, the CCT (Correlated Color Temperature) of LED lighting has a major effect on color appearance so that this study conducted an experiment through a subjective evaluation and luminance measurement for effective color appearance in a space. This study performed a subjective evaluation under the seven different LED CCT conditions, and color appearance was evaluated with major five colors in a customized lighting box. In addition, luminance measurement was conducted for each CCT and color condition to compare the results from a subjective evaluation. The results of this study may help to select a proper LED CCT for specific color conditions.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2004.10a
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• pp.49-53
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• 2004

Thin spot welding is frequently used for industrial purpose, such as automobile and aerospace industries and household appliances due to its high performance. In these days, the systemization of welding process made it possible to produce more precise or smaller electric parts. And when it comes to welding of steel sheets, the size of nugget must be getting smaller. Therefore, welding conditions are limited to avoid defects, such as deformation, damage and weakening of joining area. In this research, thin spot welding establishes the welding conditions, and then the measurement of the nugget size by the nondestructive inspection has been conducted. As a result, the right estimation of the nugget size, the detection of corona bond near joining area, the selection of the optimum ultrasonic mode, and setup for ultrasonic inspection are studied. From the trustworthy solutions of the nugget size estimated by results of measurement, the optimum inspection conditions depending upon the width of welding parts are determined as well.

• International Journal of Automotive Technology
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• v.3 no.2
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• pp.57-62
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• 2002

It is well known that the entrained air in oil causes appreciable reduction in the stiffness of hydraulic systems. It makes the response delay of the systems and sometimes destroys the stability. Because the hydraulic systems of automatic transmissions are operated in relatively low pressure and high temperature, it is very important to analyze the effects of the air included in automatic transmission fluid. However, it is difficult to derive the generalized model to describe the effective bulk modulus theoretically or measure it in actual operating conditions of automatic transmissions. This paper reviews previous studies of the air effects in hydraulic systems and the measurement techniques of the effective bulk modulus in operating conditions. Based on this work, the theoretical model with moderate complexity and the measurement technique of the effective bulk modulus considering entrained air effect at real operating conditions are suggested. Our paper also shows that the quantity of the entrained air in the automatic transmission fluid can be estimated from the experimental results.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.27 no.10
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• pp.653-656
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• 2014

$Cs_3Sb$ photocathode was formed by newly developed process and successive in-situ lighting devices were fabricated in a process chamber. R, G, and B phosphors were applied on the anode plate, respectively. Major parameters such as brightness, power consumption, and efficacy were measured. The wavelength of LED excitation source was 450 nm. Both high power and low power modes were applied in the measurement. Measurement values were clearly differentiated by the voltage application modes. The measured values of each parameter was good enough to be applied for general lighting source. The results showed that $Cs_3Sb$ photocathode formed in atmospheric conditions was functioning as good as the photocathode formed in UHV conditions, and thus it could be applied to advanced lighting devices.

• Journal of Biosystems Engineering
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• v.32 no.3
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• pp.190-196
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• 2007

The purpose of this study is to develop a measurement system of cutter conditions for combine header diagnosis during rice harvesting. A load cell was installed at the locker-arm to measure load fluctuation and an acceleration senor was used to monitor vibration signal of cutter bar. The data were collected from a paddy field during harvesting. The tests were conducted with a normal cutter, a loosened cutter, a broken cutter, and a worn-out connecter pin at the field. The vibration signals converted by FFT (Fast Fourier Transformation), filtered, and normalized. The load data and peak values of vibration signals in four different frequency ranges were used to determine the cutting operation and the cutter conditions of combine. The multiple comparison tests showed that the load data and peak values of vibration signals were important to monitor the cutting operation and cutter conditions of combine header.

• International Journal of Concrete Structures and Materials
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• v.11 no.2
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• pp.377-389
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• 2017

Tests of the lateral and torsional stability are quite sensitive to the experimental conditions, such as support conditions and loading system. Controlling all of these conditions in a full-size test is a very challenging task. Therefore, in this paper, an experimental measurement method that can control the experimental conditions using a small-scale model was proposed to evaluate the lateral and torsional stability of beams. For this, a loading system was provided to maintain the vertical direction of the load applied to the beam, and a support frame was produced to satisfy the in-plane and out-of-plane support conditions. The experimental method using a small-scale model was applied successively to the lateral and torsional behavior and stability of I-shaped beams. The proposed experimental methods, which effectively accommodate the changes in the geometry and length of the beam, could contribute to further experimental studies regarding the lateral and torsional stability of flexural members.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.23 no.2
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• pp.114-122
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• 2013

Objectives: This study was performed in order to investigate by questionnaire the factors affecting the occupational satisfaction of work-environment measurement workers, as well as to suggest fundamental materials for systematic, administrative and economic improvements which are necessary to create a vision for the future. Material and Methods: A structured questionnaire was used at a total of 152 institutions and 1,254 work-environment measurement workers throughout the country from February to September 2012. Responses came from 97 institutions (64%) and 941 work-environment measurement workers (75.1%). The factors affecting the job satisfaction of work-environment measurement workers were statistically evaluated through $x^2$-test and ordinal logistic regression analysis. Results: Major factors affecting the job satisfaction of workers in relation to work-environment measurement were working, financial, and psychological conditions (p<0.05). Conclusions: Considering the results of this study, the improvement of labor conditions should be undertaken because workers engaged in work-environment measurement are fundamental to occupational health.

• Journal of Korean Institute of Industrial Engineers
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• v.2 no.1
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• pp.61-78
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• 1976

The purpose of this study is to establish the horizontal and vertical working area which is dependent on measuring value of workers, body in order to make easy and stable working environments, and then to design the size of machines, tools and instruments in production factory because of making the practical production conditions which is the most suitable to human characteristics. But there is necessity that we have to review numeric value of measurement periodically because the size of workers' body is variable according to periodic and social circumstances. The establishment of standard working area after measurement enable us to make the best working conditions and we can design standard working table, optimum size of all machines and tools in production activity. Therefore, we can also acknowledge the importance of studying on human engineering because human engineering is necessary to reduction of fatigue in working, saving workers from industrial accidents, fail-safe system, improvement of productivity with increase in efficiency and etc. Finally, this study informs us that numeric value of measurement is larger than that of Japan, but not than that of America and Germany. So we can establish standard working area which is the most suitable for Korean inherence after measurement of detailed parts for workers' body.

• Journal of the Korean Society of Visualization
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• v.10 no.3
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• pp.30-36
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• 2012

We are planning to construct a scaled-down moderator facility to simulate the CANDU-6 moderator circulation phenomena during steady state operating and accident conditions. In the present work a preliminary experiment using a 1/40 scaled-down moderator tank has been performed to investigate the anticipated problems of the flow visualization and measurement in the planning scaled-down moderator facility. We shortly describe CFD analysis result for the 1/40 scaled-down test model and the flow measurement techniques used for this test facility under isothermal flow conditions. The Particle Image Velocimetry (PIV) method is used to visualize and measure the velocity field of water in a transparent Plexiglas tank. Planar Laser Induced Fluorescence (PLIF) technique is used to evaluate the feasibility of temperature field measurement in the range of $20-40^{\circ}C$ of water temperature using an one-color method.

• The Journal of Korean Medicine
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• v.25 no.3
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• pp.99-104
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• 2004

Objectives : To study the Live Blood Condition of chronic shoulder measurement. Methods : Twenty-one patients were studied. The observation items of the Live Blood Condition are the form's abnormality and cohesion of red blood cells, the abnormality of hemoglobin and the toxicity in plasma. Results : 1. The form's abnormality and cohesion of red blood cells observed were erythrocyte aggregation (8 persons), Rouleau (3 persons), target cells (7 persons), ovalocytes (3 persons), poikilocytes (2 persons). Double conditions observed were erythrocyte aggregation & target cells (3 persons), erythrocyte aggregation & poikilocytes (1 person), target cells & ovalocytes (l person). 2. The abnormality of hemoglobin and the toxicity in plasma observed were cholesterol crystals (5 persons), atherosclerotic plaque (3 persons), chylous (6 persons). 3. The form normality of red blood was generally observed in one woman. The normality of hemoglobin and the non-toxicity in plasma were generally observed in seven women. Conclusions : According to this study of the Live Blood Condition of women's shoulder measurement, these results suggest that the twenty-one patients evidence the conditions of extravasated blood and phlegm.