• International Journal of Automotive Technology
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• 제6권3호
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• pp.251-257
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• 2005

Several air cells are installed in the seat cushion to adjust the stiffness of seat by changing the air pressure. To select proper air pressure in the air cells, two kinds of tests are performed. For the pressure distribution on the seat, the maximum pressure and mean pressure are compared. And for the dynamic ride values, SEAT (Seat Effective Amplitude Transmissibility) values are calculated and compared. These experiments are carried out with three different drivers, three different vehicle speeds on the highway and two different speed on the primary road, and three different air pressures. From the real car tests, optimum air cell pressure depending on the vehicle speed and driver's weight are recommended.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2003년도 춘계학술대회 논문집
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• pp.610-615
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• 2003

Electric rolling stock is one of major public transportation because of an increase in population and heavy traffic problems. The passengers under the influenced of indoor air quality such as air temperature, relative humidity and air velocity. Ventilation system on passenger cars should be designed for the health and comfort of the passengers. One of the main aim is to create an acceptable thermal environment without draught problems. The draught sensation increases when the air temperature decreases and the air velocity increases. Airflow in passenger cars is turbulent. Lateral temperature and humidity gradients in the electric rolling stock have been studied. And, the difference in the mean temperature and relative humidity measured at 0.7, 0.9, 1.2, 1.7 m above from the floor.

• 대한간호학회지
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• 제34권1호
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• pp.15-24
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• 2004

Purpose: The purpose of this research was to explore the cyber world immersion experience of adolescents. Method: Multiple strategies for data collecting were used: an in depth face-to-face interview; analysis of adolescent' writings; and analysis of examples of phenomenon in the realistic world. The sample group consisted of 10 adolescents. Results: Although the experience was different for all adolescent interviewed, the essential themes of experience emerged: "fill up", "homoeologous feeling", "the older generation has a conflicting negative opinion", "change in social character", "become habitually skeptic", "have bad health", "mean of superiority and getting everything solved", "ease of access", "monetary benefit", "addiction to the computer", "forget real life solved stress", "do harm to society", "take comfort", or "new job". Conclusion: Accordingly this paper suggests that contact with various software is necessary in adolescents, and good quality contents function to prepare and activate adolescents to apply the internet for good use.

• 한국의류산업학회지
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• 제22권5호
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• pp.628-638
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• 2020

This study develops a cool-touch functional Dancesport top for middle-aged women by using cool-touch materials in areas where surface temperature becomes high after exercise. The post-exercise surface temperature of the developed research product was compared and analyzed. In addition, subjective evaluation of cool-touch as well as appearance and movement evaluations were performed. The results are as follows. In designing the research product, a detachable neckband was made using highly-preferred hydrated polymer crystals. A material with high moisture absorption speed was also used in F1, S1, under arm and B5, while a material with good thermal conductivity was used in other parts of the bodice. Deodorant tape with antibacterial and deodorant effects was incorporated in the armpit for additional comfort. As for wear evaluation of the research product, significant differences were found in 10 areas using a material with high moisture absorption speed to compare and analyze the post-exercise surface temperatures of the clothing. The temperature difference between the compared top and the research product in the neckband area was 9.16℃, demonstrating clear cool-touch function in using cool-touch material. In the subjective evaluation of cool-touch function, the results showed high scores when asked about the efficiency of the detachable neckband and the ease of movement when wearing the product. In the appearance evaluation, significant differences were found in 11 items, including redundant folds, tightfit, fit, and design line. The overall mean score of the movement evaluation was 4.6, indicating excellent function for movement.

• 한국의류학회지
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• 제11권3호
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• pp.41-55
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• 1987

The purpose of this study is to investigate the effects of napping of knitted fabric on wear sensation and physiological responses. Experimental garments were four types of warm-ups made of either $100\%$ PET or $65/35\%$ P /C and either napped or unnapped respectively. Two healthy young female adults were chosen as subjects for the experiment. Experimental room conditions were as follows: Temp., $22\pm0.5^{\circ}C$ R.H., $54\pm3\%$ and Air Velocity, 0.25m/ sec or 2. 86m/sec. The subjects exercised on bicycle ergometer and rested alternatively for totally 45-min. The results are summarized as follows. 1) With napped Warm-up, chest, back, mean skin temp. and microclimates, i.e., temp., relative humidity and water vapor pressure inside the clothing, were higher than with unnapped warm-up. And there was no difference in pulse rate between napped and unnapped warm-ups. 2) Wear sensations of thermal, humidity, tactile and comfort were 'more hot' and 'more uncomfortable' in 0.25m/sec air velocity. but in 2.86m/sec condition the tactile sensation was 'better' and 'more comfortable' with napped warm-ups. According to Pearson's Correlation, among various kinds of wear sensations, tactile is most related with comfort. From these results, it can be concluded that napped fabric decreases the rate of heat trans? mission and moisture diffusion through the clothing. Therefore skin and body temp. and temp., R.H., Vapor Pressure inside the clothing are increased.

• 한국운동역학회지
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• 제21권2호
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• pp.231-241
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• 2011

The purpose of this study was to analyze the distribution of foot pressure generated by active materials of a functional insole. Comfort is an important consideration while selectingfootwear and insoles. Consequently, it has an influence on injury. The development of new materials for functional insoles is considered one of the more important points for their manufacture. The method adopted in this study is as follows. First, ten healthy males were selected as subjects for the study. Each subject's foof was pre-screened podoscope(Alfoots, Korea) to check for the presence of any foot abnormalities, Two kinds of equipment were used for the study: a foot pressure device from Pedar-X, Germany, and a treadmill from Pulsefitness, UK. Next, each subject was asked to test four types of insoles(insoles of outdoor shoes, indoor shoes, walking shoes, and sports shoes) via walking trials on the treadmill at a constant speed of 4.2 km/h. The pressure distribution data(contact area, maximum force, maximum peak pressure, and maximum mean pressure) was collected using the pressure device at a sampling rate of 100 Hz. Results of the tests showed that all four types of functional insoles increased contact areas whit the foot. Further, functional insoles of walking shoes and sport shoes decreased the foot pressure. From these results, we conclude that the active materials of functional insoles of shoes can increase the contact area and provide greater comfort.

• 한국생활과학회지
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• 제10권1호
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• pp.101-111
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• 2001

The purpose of this study was to investigate using and evaluative criteria for purchasing of sleepwear in winter. Subjects were 523 males and females aged from twenties to fifties, living in Chongju and Taejon. For data analysis, frequency, descriptive analysis, t-test, and F-test were used. The results are as follows. First, the ownership of sleepwear was sweat suits with zippered top, pajamas, T-shirts/pants, underwear, and nightgown in order. The mean of using sweat suits was used the highest, and subjects used more home wear than sleepwear in winter. Second, the using or sleepwear had a significant difference in cold-sensitiveness and body types. Cold-sensitive group used sweat suit and T-shirts/pants more than cold-insensitive group. Also, groups who are thin wore sweat suit the most while groups who are corpulent, used underwear the most when they slept. Third, subjects, who are married women and use bed, used nightgown, but pajamas were used by groups who are older, married, and professional. Sweat suits and T-shirts/pants were used the most by single aged twenties. Forth, consumers considered the wearing comfort when they purchased sleepwear for winter, and they evaluated washing/management, fabric, design/style, economic, service, brand, and others' response in order, for judging the quality of sleepwear. Also, the evaluative criteria had a significant difference in demographic variables such as sex, occupation, and marital state. These results implied that sleepwear would be needed for winter in terms of behavioral temperature regulation. Especially, cold-sensitive and thin group would wear knitted and two-piece sleepwear for thermal comfort when they sleep in winter. Also, Using and evaluative criteria of sleepwear would be different in demographic characteristics. For winter, sleepwear should be develop based on physiologic as well as demographic variables.

• Wind and Structures
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• 제25권1호
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• pp.63-77
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• 2017

When railway vehicles run by towers of long span bridges, the railway vehicles might experience a sudden load-off and load-on phenomenon in crosswind conditions. To ensure the running safety of the railway vehicles and the running comfort of the passengers, some studies were carried out to investigate the impacts of sudden changes of aerodynamic loads on moving railway vehicles. In the present study, the aerodynamic coefficients which were measured in wind tunnel tests using a moving train model are converted into the aerodynamic coefficients in the actual scale. The three-component aerodynamic loads are calculated based on the aerodynamic coefficients with consideration of the vehicle movement. A three-dimensional railway vehicle model is set up using the multibody dynamic theory, and the aerodynamic loads are treated as the inputs of excitation varied with time for kinetic simulations of the railway vehicle. Thus the dynamic responses of the railway vehicle passing by the bridge tower can be obtained from the kinetic simulations in the time domain. The effects of the mean wind speeds and the rail track positions on the running performance of the railway vehicle are discussed. The three-component aerodynamic loads on the railway vehicle are found to experience significant sudden changes when the vehicle passes by the bridge tower. Correspondingly, such sudden changes of aerodynamic loads have a large impact on the dynamic performance of the running railway vehicle. The dynamic responses of the railway vehicle have great fluctuations and significant sudden changes, which is adverse to the running safety and comfort of the railway vehicle passing by the bridge tower in crosswind conditions.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 추계학술대회 논문집 전력기술부문
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• pp.145-147
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• 2005

This paper presents a methodology for satisfying the thermal comfort of Indoor environment and reducing the summer peak demand power by minimizing the power consumption for an Air-conditioner within a space. KEPCO(Korea Electric Power Corporation) use the fixed duty cycle control method regardless of the indoor thermal environment. This method has disadvantages that energy saying depends on the set-point value of the Air-Conditioner and DLC has no net effects on Air-conditioners if the appliance has a lower operating cycle than the fixed duty cycle. A variable duty cycle estimates the PMV(Predict Mean Vote) at the next step with a predicted temperature and humidity coming from the back propagation neural network model. It is possible to reduce the energy consumption by maintaining the Air-conditioner's OFF state when the PMV lies in the thermal comfort range. The proposed methodology uses the historical real data of Sep. 7th, 2001 from a classroom in seoul to verify the effectiveness of the variable duty cycle method comparing with fixed duty cycle. The result shows that the variable duty cycle reduces the peak demand to 2.6times more than fixed duty cycle and increases the load control ratio by 8% more. Based on the variable duty cycle control algorithm, the effectiveness of DLC is much more improved as compared with the fixed duty cycle.

• 국제초고층학회논문집
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• 제1권1호
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• pp.15-19
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• 2012

Occupant footfalls are often the most critical source of floor vibration on upper floors of buildings. Floor motions can degrade the performance of imaging equipment, disrupt sensitive research equipment, and cause discomfort for the occupants. It is essential that low-vibration environments be provided for functionality of sensitive spaces on floors above grade. This requires a sufficiently stiff and massive floor structure that effectively resists the forces exerted from user traffic. Over the past 25 years, generic vibration limits have been developed, which provide frequency dependent sensitivities for wide classes of equipment, and are used extensively in lab design for healthcare and research facilities. The same basis for these curves can be used to quantify acceptable limits of vibration for human comfort, depending on the intended occupancy of the space. When available, manufacturer's vibration criteria for sensitive equipment are expressed in units of acceleration, velocity or displacement and can be specified as zero-to-peak, peak-to-peak, or root-mean-square (rms) with varying frequency ranges and resolutions. Several approaches to prediction of floor vibrations are currently applied in practice. Each method is traceable to fundamental structural dynamics, differing only in the level of complexity assumed for the system response, and the required information for use as model inputs. Three commonly used models are described, as well as key features they possess that make them attractive to use for various applications. A case study is presented of a tall building which has fitness areas on two of the upper floors. The analysis predicted that the motions experienced would be within the given criteria, but showed that if the floor had been more flexible, the potential exists for a locked-in resonance response which could have been felt over large portions of the building.