• The Proceedings of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.10 no.5
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• pp.101-107
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• 1996

This paper proposed the voltage compensation analysis method in distribution system by EMTP. SVC (Static Var Compensator) of the thyristor controlled reactor type is used for compensation system. EMTP(E1ectr-o Magnetic Transient Program) model of SVC is proposed to analysis the voltage improvement characteristics at the high voltage system bus. It is composed with three parts ; rms detector, voltage regulator and gate pulse generator. The control signal of TCR is determined by rms value which was measured in system. As the result of EMTP simulation, all of the SVC characteristics like TCR current, firing pulse and bus voltage is very reliable. This method could be used to analysis the planning and the operation of compensation system in the large scale factory.

• Nutritional Sciences
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• v.9 no.3
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• pp.195-200
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• 2006

We surveyed Korean pregnant women who participated in the Maeil mothers' club and factory tour from March to April, 2004 and assessed volunteers' hemoglobin (Hb) levels. The average Hb level of 747 subjects was $11.5{\pm}1.5g/dl$ and anemic subjects were 268 women, 35.9% of total subjects. The ratio of anemic subjects was 42.9% in the first trimester, 43.6% in the second trimester and 29.1 % in the third trimester. About 87.9% of subjects began to take health foods after conception. Seventy nine percent of subjects took iron supplement as one of health foods and 73.8% of them began it in the second trimester. The results of this study showed that health foods were more effective than iron supplement alone in improving the iron status of Korean pregnant women. Therefore, the better improvement effects are expected when pregnant women begin health food-based approaches as early as possible before pregnancy to improve pre-pregnancy iron reserve.

• Journal of Korean Society for Quality Management
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• v.19 no.1
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• pp.115-128
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• 1991

In korea, since November 1982 these two small group actvity convension (QC circle convension and Factory Saemaul activity small group convension) has been united, many problem have been disclosed that are against the basic principle more or less. Worker's small group activity is essentially, a trouble shooting oriented voluntary small group within their working place to improve the surroundings creatively. In practice. however, many group are so typical and so impetuous of the material effect that it is worried to be inclined to outform rather than contents. Effective small group activities are presumed to be successful only with labor management cooperation on the basis of human-orient management philosophy. The small group activities are also prevalent in service sector. More derivative methods have been developed and more members are willingly participating in training programs. The small group which is basically a horizontal organization unit, promptes communication within the whole organization. In consideration of the social circumstances and traditions, the flexible model of the small group activities suitable to the corporate environment, will contribute industrial development.

• Fire Science and Engineering
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• v.15 no.2
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• pp.53-58
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• 2001

This study was undertaken to evaluate the performance of flame retardant for fire precaution from sparks at welding-cutting process in industry sites such as shipbuilding yard and chemical factory. As the results of the performance experiment, six kinds of welding blanket in samples that are used commercially had enough in the performance of flame retardant. Nevertheless, the performance to fire precaution un welding blanket shows that the coaling product of two kinds with fiber glass is not sufficient. The lower oxygen index to welding blanket is considered that it is more than 30 in domestic standard. We suggested that the performance improvement of flame retardant for welding blanket need continuously, and the guideline of the flame retardant to welding blanket should be considered and established.

• Journal of Digital Contents Society
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• v.7 no.3
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• pp.169-174
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• 2006

In recent years, RFID is widely used in industrial applications including factory, material flow, logistics and defense areas. In this paper, The convolutional encoding and viterbi decoding is also implemented to improve the system performance. in an FPGA chip. The used convolution code is constraint length K=3 and rate R=1/2. The length of command frame and response frame is total of 48bits consisting of SOF 8 bits, command 16 bits, CRC 16 bit, and EOF 8 bits. And also the frame error rates are measured under the channel of line-of-sight and non line-of-sight, respectively. The performances are analyzed with FSK modulation only and FSK modulation added with convolutional encoding. These two measured results are compared with that of a RFID system with ASK modulation.

• The Research Journal of the Costume Culture
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• v.10 no.6
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• pp.718-734
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• 2002

The purpose of this study is to provide basic data f3r improvement in Working Uniform in both scientific and efficient ways. The study were enforced by questionnaire and personal interview. The subject of the survey were the workers of 264 in mechanic industry in Seoul. The results obtained from the researches by methods above are as follows. 1. In general, Working Uniform could be classified types of two. One is loose-fitting one-piece garment covering the body and legs, the other is two-piece garment. The latter is a jacket with either sports collar or soutein collar, fastened with either buttons or a zipper and its sleeve is finished by cuffs and tapes. Regarding to color. inkblue, dark navy, khaky, dark beige are favourable ones. 2. In regard to the necessity of uniform that workers suppose, most of them were aware of it and agreed wearing uniform could play an important part. The reason why are on the basis of safety-first and work efficiency and also to protect a body from harmful or toxic dirt specially in machinery workplace. 3. The purpose of wearing an uniform according to statistics of population make some difference in age, gender. categories of industry, and the scale of factory. 4. In regard to care of uniform, front hem, edge of sleeve in a jacket, and knee, hip part in pants were most vulnerable spots for dirt. The parts damaged easily are edge of sleeve in a jacket and a zipper in pants. On the average, laundry have been done by water and was once a week frequency.

• Environmental Engineering Research
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• v.13 no.3
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• pp.112-118
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• 2008

Residual solid in excess sludge treated by hydrothermal reaction was investigated as raw material for its recycling. Treated excess sludge and residual solid were also focused on their content change during hydrothermal reaction. Two kinds of excess sludge, obtained from a local food factory and a municipal wastewater treatment process, were tested under various conditions. Following hydrothermal reaction, depending on the reaction conditions, biodegradable substrates in treated excess sludge appeared to increase. The separated residual solid was a composite composed of organic and inorganic materials. The proportion of carbon varied from 34.0 to 41.6% depending on reaction conditions. Although 1.89% of hazardous materials were detected, SiO2 (Quartz) was a predominant constituent of the residual solid. X-ray diffraction (XRD) experiments revealed that the residual solid was of a partially amorphous state, suggesting that the residual solids could be easily converted to stable and non harmful substances through a stabilization process. Thus, this technology could be successfully used to control excess sludge and its reuse.

• Journal of Convergence for Information Technology
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• v.9 no.1
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• pp.136-141
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• 2019

In this paper, we describe the design of a small size data acquisition system with STM32 processor based on Cortex-M4. The system is used for the sensor devices to collect raw data on production lines at factory and send them to the server computer in real time. Also the system is designed to easily acquisite various kinds of data collected from various sensors with the digital signal input unit, the analog signal input unit, the digital signal output unit and the analog signal output unit This small data acquisition system will contribute to the improvement of the quality of precision products in the industrial field by collecting various data in real time and transmitting data at high speed.

• Journal of the Korea Institute of Building Construction
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• v.22 no.6
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• pp.673-680
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• 2022

Modular construction is recognized as a construction method with various advantages, such as shortening the construction duration, achieving quality control through factory production, ease of maintenance, and reduced construction costs due to reduced weight of materials. However, despite efforts by the modular industry and government to activate modular construction, it has rarely been established in the domestic market. Currently, there are technical limitations to the modular construction fire resisting technology applied to general buildings. The lack of access to modular construction fire resistance regulation is considered a major factor. In this study, the current status and problems with modular construction fire resistance regulation, a significant hindrance factor, were considered to activate modular construction. This study is intended to present a direction for institutional improvement in modular construction fire resistance and a direction for research and development.

• International Journal of Advanced Culture Technology
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• v.10 no.1
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• pp.253-264
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• 2022

In the era of the pandemic, the importance of a wireless LAN environment has become increasingly important, especially as the era of smart working and non-face-to-face education has become a universal and daily routine. Smartphones, tablets, laptops, PCs, smart watches, and wearable devices, collective referred to as wireless terminals, can be accessed anytime and anywhere through the internet, allowing for consistent and constant access to offices, factories, warehouses, shopping malls, railways, hotels, hospitals, schools, logistics centers, airports, exhibition halls, etc. This sort of access is currently being used in roads, parks, traditional markets, and ports. Since the release of the IEEE 802.11 Legacy Standard in 1997, Wi-Fi technology has been continuously supplemented and revised, and the standard has been continuously developed. In the era of smart working, the importance of efficient wireless deployment and scientific design has become more important. The importance of wireless in the smart factory, in the metaverse era, in the era of pursuing work and life that transcend time and space by using AR, VR, MR, and XR, it is more urgent to solve the shadow area of Wi-Fi. Through this study, we intend to verify the wireless failure problem of the xr training center and suggest improvement measures.