• Journal of the Korean Solar Energy Society
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• v.31 no.6
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• pp.78-85
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• 2011

In this study, an underfloor air distribution(UFAD) system installed on the S. office building was evaluated for its indoor environmental quality performance. Field measurement and survey were conducted for the overall POE(Post Occupied Evaluation). PMV(including temperature, humidity, air velocity and globe temperature) and several environmental components were measured while thermal comfort, thermal sensation, acoustical environment and others. were investigated through survey. Except for the direct upper part of the air supply diffuser on the floor, the indoor velocity was less than 0.25m/s, which has been suggested by ASHRAES tandard 55 as the limit for thermal comfort. MRT of the perimeter zone of the room showed a higher value than that in the interior because of the introduced solar radiation through the building envelope. PMV was generally maintained in the range of thermal comfort (from -0.5 to +0.5), though it weighted to the warm side. It was reported to have 61% positive response on thermal comfort and 55% on neutral thermal sensation. The results of each survey item showed some gender-based differences. Specifically, female respondents had higher degree of dissatisfaction with indoor air cleanness and acoustical privacy. The working surface showed more than 400 lux and the equivalent noise level showed less than 50 dB(A). In conclusion, the results of the measurement and survey showed good agreement. Indoor environmental quality of the subject office room where the UFAD system was installed showed an overall excellent performance.

• Journal of the Korean Society of Industry Convergence
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• v.1 no.1
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• pp.21-30
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• 1998

The purpose of this study is to clarify the floor temperature on the human body and to estimate thermal comfort zone in a heated room. In order to evaluate the effects of floor heating, a series of experiments were carried out using Korean subjects. The following experiments were conducted: 1) to obtain the effective radiation area and configuration factors of the person in the sitting posture on a floor to get the mean radiant temperature, 2) to measure contacted area of the person to the floor to calculate conduction heat rate, 3) to measure convective heat transfer coefficient of the body and 4) to know the thermal comfort zone of indoor environment heated by ON-DOL. Subjects were exposed to the following conditions: combinations of air temperature $20^{\circ}C$, $22.5^{\circ}C$, $25^{\circ}C$, and floor temperature $20^{\circ}C$, $22.5^{\circ}C$, $25^{\circ}C$, $27.5^{\circ}C$, $30^{\circ}C$, $32.5^{\circ}C$, $35^{\circ}C$, $37.5^{\circ}C$, $40^{\circ}C$ under still air and 50% relative humidity in the controllable artificial climate chamber. To evaluate the effect of heat conduction between the body and a floor modified mean skin temperature was defined. Weighting coefficient to calculate mean skin temperature were modified with the contacted area. The experiments revealed a positive correlation between the modified operative temperature and the modified mean skin temperature. The modified mean skin temperature can indicate the effect of heat conduction between body and a floor surface.

• Journal of Korea Multimedia Society
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• v.16 no.8
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• pp.994-1004
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• 2013

3D stereoscopic cinema emerged as a new dominant media format. In principle, the stereoscopic cinema imitate the vision of the human being has two eyes. The stereoscopic cinema is filmed with 2 connected cameras at the same time and projected these 2 different images. With the stereoscopic glasses, the human being can see the overlapped images as a single 3D stereoscopic image. To make 3D stereoscopic cinema, it is very important to systemize the process of the 3D stereoscopic cinema production and to use the principle of the 3D stereoscopic cinema. This paper investigates the possibilities of the using the 3D stereoscopic principles such as the I.O.D, convergence point, parallax and the 3D comfort zone. Using the principle of the 3D stereoscopic cinema can be the technique of directing the film. Using the example of 3D stereoscopic short film My Birthday, I investigate the main technique of the 3D stereoscopic cinema.

• Journal of Navigation and Port Research
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• v.32 no.6
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• pp.505-513
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• 2008

Regarding the developmental plans for the coastal areas and marine architectures, this study deal with the overall planning of apartment complexes in waterfront areas, focusing upon the analysis of their comfort and convenience factors from the perspective of the potential residence. It also analysis the intra-complex comfort and satisfaction conditions in terms of their floor-by-floor, directional. and location factors. The results of the study are as follows: 1) The order of respondents' preference on directional factor has been found to be: South > Southeast > Southwest > East > others. 2) 67% of the people surveyed on scenery responded that outward view is considered more significant than the directional factor. 3) A comprehensive analysis of floor zone-specific view preference shared that there were only minor differences among quay wall, arc, and river-seashore types. The impact of the characteristics of the marine environments turned out to be a greater point of consideration; showing that the other of floor-preference is: high-level > ultra-high level > middle level > low level.

• Journal of the Korean Society for Railway
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• v.15 no.1
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• pp.48-61
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• 2012

It is of great importance to assure the running safety, ride comfort and serviceability in designing the floating slab track for mitigation of train-induced vibration. In this paper, for this, analyzed are the system requirements for the running safety, ride comfort and serviceability, and then, the behavior of train and track at the floating slab track including the transition zone to the conventional concrete slab track according to several main design variables such as system natural frequency, arrangement of spring at transition, spacing of spring isolators, damping ratio and train speed, using the dynamic analysis technique considering the train-track interaction. The results of this study demonstrate that the discontinuity of the support stiffness at the transition results in a drastic increase of the dynamic response such as wheel-rail interaction force, rail bending stress and rail uplift force. Hence, it is efficient to decrease the spacing of springs or to increase the spring constants at the transition to obtain the running safety and serviceability. On the other hand, the vehicle body acceleration as a measure of ride comfort is little affected by the discontinuity of the stiffness at the transition, but by the system tuning frequency; thus, to obtain the ride comfort, it is of great significance to select the appropriate system tuning frequency. In addition, the effects of damping ratio, spacing of springs and train speed on the dynamic behavior of the system have been discussed.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.59 no.2
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• pp.291-297
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• 2010

A system called demand response programs (DRP) is being introduced among various countries owing to the lack of new generation capacity and the higher fuel generation cost. It is a program which provides for the end-users to select their consumption of electricity by recognizing the value of their consumption in real time. That is, Demand Response can be defined as the changes in electric usage by end-use customers from their normal consumption patterns in response to changes in the price of electricity or other signals. It is expected that the effects of DRP are preventing price spike, improving supply reliability and social welfare and increasing option of customers. Considering the customer's thermal comfort zone, this paper determines the most profitable combination of optimal incentives and amounts of load reduction for a retailer to maximize profits according to predicted outdoor temperatures while implementing DRP.

• KIEAE Journal
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• v.7 no.5
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• pp.87-92
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• 2007

As expansion of balconies at apartments has been legalized, the major function of the balconies as a thermal buffer zone is disappearing. This weakens the ability of window to insulate heat and multiplies surface condensation. Thus more and more residents require solutions to increasing surface condensation and aggravation in thermal comfort. This study intends to provide basic data by evaluating performance of triple layered Low-E windows, triple layered clear windows, double layered Low-E windows and double layered clear window used for expanded balconies and marketed within the country in terms of surface condensation and thermal environment through simulation. Results revealed that no surface condensation occurred at double layered Low-E windows and triple layered Low-E windows. Surface condensation took place at double layered clear windows and triple layered clear windows at a relative humidity of 60%. Thermal environment analysis suggested that double layered clear windows showed the most time falling into the range of comfort at $23^{\circ}C$. The figure were $22^{\circ}C$ for triple layered clear windows, $22^{\circ}C$ for double layered Low-E windows and $21^{\circ}C$ for triple layered Low-E windows.

• Ecology and Resilient Infrastructure
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• v.5 no.4
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• pp.219-228
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• 2018

This study measured the Physiological Equivalent Temperature (PET) of the hottest day time in a day, in order to verify the characteristics of human thermal comfort in case of heat wave during summer time in each region, by subdividing the urban areas in accordance with the climatic characteristics with the use of Local Climate Zone (LCZ) as a method of classifying the type of urban climate and the land cover map, targeting the Homaesil residential development district in Suwon. In the results of measurement, the forest and paddy field showed the moderate heat stress while the urban park showed the strong heat stress. Other developed areas showed the extreme heat stress. Such results show the possibility of institutional utilization for the improvement of human thermal comfort through the verification of climatic characteristics and differences in each type of urban areas, and the efficient placement of green infrastructure and the planning of land use to cope with the heat wave even in the planning stage for the establishment of urban planning.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.37 no.8A
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• pp.698-705
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• 2012

In this paper, we proposed an autostereoscopic display simulator that calculates an extended intensity distribution of light emitted from respective light sources and reaching respective views in an observing area to an observing plane. It simulates intensity distribution in horizontal and vertical observing ranges from the predetermined observing plane and obtains an optimal viewing area image having quantities of light according to respective views based on the intensity distribution data. As a result of the simulation the proposed system enables guiding viewing comfort zone interactively.

• Journal of the Korean Solar Energy Society
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• v.31 no.6
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• pp.111-124
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• 2011

The objective of this study is to develop the blind control strategy and method which reduce negative effect of incoming daylight on visual comfort of occupants, minimize psychological anxieties caused by frequent motions of a blind, and maximize positive effect of incoming daylight by opening/closing of a blind. In previous researches on blind controls, major problem is that the time interval and amount of blind movement do not meet the control objective at the inflected zone of solar profile curve. To overcome these limitations revealed in theprevious researches, following tasks were performed in this study. i)To establish the control objective to accomplish the goal of this study. ii)To develop the control methods and algorithms which prevent glare on the work-plane at any time and which control the time interval and amount of blind movement to follow the control objective at various solar profile angle curves. This study proposed the control strategy and method that define the base control section implying the inflection point within the control objective zone and subsequently, divide the control sections for the residual time zones. The proposed strategy and method are found to increase the incoming daylight and solar irradiation by 0 to 15 %.