• Proceedings of the Korea Institute of Applied Superconductivity and Cryogenics Conference
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• 2002.02a
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• pp.189-192
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• 2002

In this study, The experimental open-tube-type and close-tube-type thermoacoustic refrigerator were constructed. The resonant characteristics of a thermoacoustic refrigerator were investigated. In order to determine the optimum resonant tube length and frequency, We changed the length of resonant tube from 400mm to 850mm and the frequency from 100Hz to 1000Hz. In case of first harmonic, the temperature difference of open-tube-type (1/4 wave) refrigerator was $41^{\circ}C$(resonator length :500mm). The temperature difference of close-tube-type (1/2 wave) refrigerator was $43^{\circ}C$(resonator length :850mm). In this experiments, the experimental 1/2 wave refrigerator is slightly cooler than the experimental l/4 wave refrigerator.

• Journal of the Korean Society of Clothing and Textiles
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• v.20 no.3
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• pp.452-466
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• 1996

The purpose of this study is to proviede basic data for designing sports-brassiere by a questionnaire survey about sports-brassieres preferences and physiological wearing test. The results of the survey and the physiological wearing tests on sports-brassieres are as follow; 1. According to the survey, dissatisfied factors on the sports-brassiere are "drooping and vibrating of the breasts". Preferable factors are supporting breasts by stretch and seldom changing its position by motion. The bigger cup-size and more hemispherical-type causes more discontent than flat-type. 2. The shape of breasts is oval, on what ground, horizontal line is longer than vertical. For the cross section of bust line, shirts type.brassiere is more gently curved than cup-brassiere. 3. The feeling of wearing comfort is correlated with bust.up, shield, close adhesion. The vibration of breasts is correlated with covering urea and close adhesion, and the changing band's position by movement, close adhesion. Too much covering area or strain are in inverse correlation of the comfort. 4. The rate of prevention of vibration is 75~80% on superior sports-brassieres, which has broad covering area and excellent close adhesion. adhesion.

• New & Renewable Energy
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• v.3 no.4
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• pp.47-53
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• 2007

Effluent ground water overflow in deep and broad ground space building. Temperature of effluent ground water is in $12{\sim}20^{\circ}C$ annually and the quality of that water is as good as living water. Therefore if the flow rate of effluent ground water is sufficient as source of heat pump, that is good heat source and heat sink of heat pump. Effluent ground water contain the thermal energy of surrounding ground. So this is a new application of ground source heat pump. In this study open type and close type heat pump system using effluent ground water was installed and tested for a church building with large and deep ground space. The effluent flow rate of this building is $800{\sim}1000ton/day$. The heat pump capacity is 5RT each. The heat pump cooling COP is $4.9{\sim}5.2$ for the open type and $4.9{\sim}5.7$ for close type system. The system cooling COP is $3.2{\sim}4.5$ for open type and $3.8{\sim}4.2$ for close type system. This performance is up to that of BHE type ground source heat pump.

• New & Renewable Energy
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• v.3 no.2 s.10
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• pp.40-46
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• 2007

Effluent ground water overflow in deep and broad ground space building. Temperature of effluent ground water is in $12{\sim}20^{\circ}...$ annually and the quality of that water is as good as well water. Therefore if the flow rate of effluent ground water is sufficient as source of heat pump, that is good heat source and heat sink of heat pump. Effuent ground water contain the thermal energy of surrounding ground. So this is a new application of ground source heat pump. In this study open type and close type heat pump system using effluent ground water was installed and tested for a church building with large and deep ground space. The effluent flow rate of this building is $800{\sim}1000\;ton/day$. The heat pump capacity is 5RT. The heat pump heating COP was $3.85{\sim}4.68$ for the open type and $3.82{\sim}4.69$ for the close type system. The system heating COP including pump power is $3.0{\sim}3.32$ for the open type and $3.32{\sim}3.84$ for close type system. This performance is up to that of BHE type ground source heat pump.

• The Journal of Information Systems
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• v.29 no.2
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• pp.71-94
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• 2020

Purpose With the development of Social Network Service(SNS) and mobile devices, many companies have been using the Facebook as a Word-of-Mouth(WOM) channel. This study examines the effects of psychological distance and message type on WOM using the Facebook's real messages. And the moderating effect of the message type on the relationship between psychological distance and WOM was also analyzed. Design/methodology/approach A content analysis was used as a research method. A total 7,483 messages were collected from 50 companies' Facebook Fanpage (based on the ranking of socialbakers.com) and content analysis was conducted using human coding. As the influencing variables, the message type and psychological distance and the number of 'Likes', 'Share', and 'Comment' were used as the dependent variable. The R3.4.4 was used to perform descriptive statistics, cross-tab analysis, and analysis of variance(ANOVA). Findings First, a larger proportion of Facebook messages have close psychological distance for all message types(information, advertisement, event, and customer relationship). Second, 'Like' and 'Comment' number were significantly higher in messages of close psychological distance. Third, the effects of psychological distance on 'Like', 'Share', and 'Comment' number were different according to message type. However, 'advertisement' message type had significantly more numbers for all WOMs('Like', 'Share', and 'Comment') in messages with close psychological distance.

• 제어로봇시스템학회:학술대회논문집
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• 2005.06a
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• pp.575-579
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• 2005

In this paper, the development of an IMM(Injection Molding Machine) controller is discussed. Presently, the Mold Close and Open Control Method of a toggle-type IMM is open-loop control. Through the development, a PC based control system was built instead of an existing controller and a closed-loop control replaced the previous control method by using PC based PLC. To control the nonlinear system of toggle type clamping unit, a fuzzy PI control algorithm was selected and it was programmed by an IL(Instruction List) and a LD(Ladder Diagram) on a PC based PLC. The application of fuzzy algorithm as the control method was also considered to change a control object like a mold replacement or an additional apparatus. For the development of an IMM controller, PC based PLC of PCI card type, distributed I/O modules with CANopen and Industrial PC and HMI (Human Machine Interface) software were used.

• 한국해양학회지
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• v.30 no.4
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• pp.262-270
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• 1995

A comparative study to understand the changes in physical and sedimentological natures was carried out in the Keum Estuary before and after the gate-close of Keum River weir. After closing of weir-gate maximum tidal current speed decreased about 30∼40% compared with that of the previous gate-opening period. Water masses also represent vertical stratifications both on water salinity and water transparency. The Keum Estuary seems to be changed from the well-mixed type estuary during the gate-opening period to the "partially-mixed type" and/or "salt-wedge type" estuary after the closing of weir-gate. The concentrations of suspended matter range 10∼100 mg/l in surface waters after the gate-close of Keum River Weir, representing about 1/4 to 1/3 decrease than those during the gate-close of Keum River Weir, representing about 1/4 to 1/3 decrease than those during the gate0opening period. Such decrease of suspended mater appears to be due to the decrease in the resuspension of bottom sediments, and also due to the vertical stratification of water masses that prevented the upward diffusion of turbid bottom waters. It is, therefore, expected that the depositional environment of Keum Estuary has been changing into the low energy conditions after the closing of weir gate, resulting in the rapid deposition of fine suspended matters within the Keum Estuary.

• Fashion & Textile Research Journal
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• v.10 no.6
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• pp.979-988
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• 2008

The purpose of this study is to analyze the lower body size and forms of married women in their thirties who have experienced pregnancy and parturition. Their measurements derived from the direct anthropometry and indirect photographic measures were compared to those of 20's. Improving consumer satisfaction for missy brand, especially in fitness of skirt and pants, some lower body classification were presented. The results were as follows : 1. The characteristics of lower body showed many differences by individuals especially in depth, girth, length and angle measures rather than height and breadth measures. Many items including index, calculations and angles revealed significant differences compared to those of 20's. Several breadth items, crotch length had distinct increase than those of women in twenties. Flattened buttocks side silhouette from waist to hip, buttocks drooping and decrease of inclination implied the influence of pregnancy, parturition and aging. 2. We hardly find out sizing system differences between missy brand and miss brand. Based on waist and hip girth measurements of subjects, sizing system of missy apparel wasn't suitable for their body size. Excessive drop(hip girth-waist girth) of missy brands, 25~30 cm, was almost the same to the drop of miss brands. 3. To improve the size satisfaction of missy women, we classified the lower body into 5 types according to drop, buttocks angle and hip length. Type 1 was small waist with large buttocks projection, and hip length was close to an average. Type 2 was small waist with medium buttocks projection, and the hip length was close to an average. Type 3 was medium waist, with average projection of the buttocks and hip length. Type 4 was large waist, projection of the buttocks and the hip length were close to an average. Type 5 was large waist, projection of the buttocks was small and the hip length was close to an average.

• ETRI Journal
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• v.38 no.1
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• pp.149-158
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• 2016

In the field of augmented reality technologies, commercial optical see-through-type wearable displays have difficulty providing immersive visual experiences, because users perceive different depths between virtual views on display surfaces and see-through views to the real world. Many cases of augmented reality applications have adopted eyeglasses-type displays (EGDs) for visualizing simple 2D information, or video see-through-type displays for minimizing virtual- and real-scene mismatch errors. In this paper, we introduce an innovative optical see-through-type wearable display hardware, called an EGD. In contrast to common head-mounted displays, which are intended for a wide field of view, our EGD provides more comfortable visual feedback at close range. Users of an EGD device can accurately manipulate close-range virtual objects and expand their view to distant real environments. To verify the feasibility of the EGD technology, subject-based experiments and analysis are performed. The analysis results and EGD-related application examples show that EGD is useful for visually expanding immersive 3D augmented environments consisting of multiple displays.

• Journal of Korea Society of Industrial Information Systems
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• v.20 no.1
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• pp.49-55
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• 2015

This paper proposes a 2.4 GHz RF oscillator with a very low close-in phase noise performance. This is composed of a low frequency crystal oscillator and three frequency multipliers such as two doubler (X2) and one tripler (X3). The proposed oscillator is implemented as a hybrid type circuit design using a discrete silicon bipolar transistor. The measurement results of the proposed oscillator structure show -115 dBc/Hz close-in phase noise at 10 kHz offset frequency, while only dissipating 5 mW from a 1-V supply. Its close-in phase noise level is very close to that of a low frequency crystal oscillator with little degradation of noise performance. The proposed structure which is consisted of a low frequency crystal oscillator and a frequency multiplier provides new method to implement a low power low close-in phase noise RF local oscillator.