• 한국태양에너지학회:학술대회논문집
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• 2012.03a
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• pp.457-462
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• 2012

Daylighting software is an important component to predict the performance of daylighting system in advance of a field demonstration study with installing them in buildings. PHOTOPIA is a powerful software to generate a candela distribution curve(CDC) of an active daylighting system like a tracking dish concentrator. With PHOTOPIA, a set of candela distribution curves was generated under clear sky conditions and different solar altitude angles. The candela distribution curves were then imported to RADIANCE for rendering and analysis on the daylighting performance of a tracking dish concentrator when it installed in a actual class room without windows. As a result, the daylight collection efficiency of the dish concentrator was 68.4% when we assumed that there was no tracking error. It was found that candela(cd) and total lumens(lm) increased with solar altitude rising, whereas the distribution angle was fixed. The illuminance uniformity on the work plane in the class room was relatively low, 0.12, while the illuminance uniformity on the area of $2.7m^2$ to which the light was illuminated was considerably high, 0.60. The maximum illuminance was 1,340lux with a solar altitude angle of 80 degrees.

• Journal of the Korean Solar Energy Society
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• v.31 no.6
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• pp.103-110
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• 2011

The aim of this study was to analysis the Heating/cooling performance and Daylighting performance of Solar Window System built in apartments. the solar window is the idea to integrate daylight as a third form of solar energy into a PV/Solar Collector system. The process of this study is as follows: 1)Solar Window system was designed through the investigation of previous paper and work. 2)The simulation program(Lightscape3.2) was used in daylighting performance analysis. the reference model of simulation was made up to analysis daylighting performance on Solar Window system. 3)The simulation program(ESP-r, Therm5.0, Window6.0) was used in energy performance analysis. the reference model of simulation was made up to analysis energy and daylighting performance on Solar Window system. 4)The Size of Simulation model for daylighting and heating/cooling energy analysis was $148.5m^2$ 5)The lighting performance analysis was carried out with various variants, such as the size and installed area of Solar Window system. 6)Energy performance simulation was carried out with various variants, such as Integrated U-value of Solar Window system according to its position, installed angle and insulation thickness. Consequently, When Solar Window system is equipped with balcony window of Apartment, Annual heating and cooling energy of reference model was cut down at the average of $4.1kWh/m^2$ or 4.2%.

• Journal of the Korean Solar Energy Society
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• v.35 no.3
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• pp.27-39
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• 2015

Under the goal of analyzing the compulsory supply share of new renewable energy according to the application of a daylighting system to indoor gymnasiums, this study conducted analysis of energy consumption and operation schedule at three indoor gymnasiums in the nation through a survey. The investigator did an Energy Plus simulation on Building A based on the analysis results and analyzed the supply share of new renewable energy in the saving effects of lighting energy according to the application of a daylighting system. As a result, When 92 prism daylighting system were installed in the upper ceiling of a stadium, they were able to meet the criteria for the minimum illumination for official games(Min : 600㏓) and optimum illumination for general games and recreations, thus saving lighting energy during the daytime(09:00~17:00). The resulting saving effects of lighting energy amounted to 44.4% for official games, 57.6% for general games, and 66.7% for recreations. In addition, the daylighting systems had a compulsory supply share of new renewable energy at 2.04% for official games, 2.75% for general games, and 2.62% for recreations, recording an average compulsory supply share of 2.5%.

• 한국태양에너지학회:학술대회논문집
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• 2008.04a
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• pp.117-122
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• 2008

The apartment will be much more convenient than the other one in the application of green technologies, providing the merits by mass production. For example, pre-manufactured building materials can be effectively adapted to the formation of buildings. Recently, the form of double-enveloped window system has been developed for the purposed of minimizing energy loss occurred around windows. On the other hand, the expansion of balcony area was legalized and thus, a visual buffer area does not exist any more. All-glass window wall on apartment houses without a balcony produces pretty harmful area with direct sunbeam. A various types of glass can be applied to the window system and it plays a critical role in the determination of inner visual environment. For the purpose of verifying the potential of its daylighting, a mock-up model has been constructed and tested. The refurbished version of conventional window shows its illuminated characteristics. Clear and Low-e glass have been adapted for window area and daylighting ratio has been compared in both test cells.

• KIEAE Journal
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• v.6 no.1
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• pp.3-10
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• 2006

As has been expected, economic factors are a major consideration in almost every decision in building design process. Assuming that improving a lighting system, existing or proposed, will reduce operating cost, what preliminary economic guidelines can be established to determine whether any proposed investment appears cost effective? In such a case a reasonable technique to compare system costs is by life-cycle costing. Stated simply, a life-cycle cost represents the total cost of a system over its entire life cycle, that is, the sum of first cost and all future costs. This paper aims to exemplify the benefit of daylighting in term of economic consideration. Four different electric lighting system designs are proposed and a lighting control system that is continuously operating according to the level of daylight in the space has been adapted. The accumulated performance of electric and daylighting is figured out to declare the effective depth of daylight in the space. The analysis on the saving amount of lighting energy due to daylight has been undertaken in answer to the question, that is, several projects are being considered, which is the most desirable from the cost-effectiveness viewpoint. The result shows clearly that although denser layout of lighting fixtures might be more effective to interface to the level of daylight ceaselessly changeable, its economic benefit may not meet the expected criterion the reason of increased initial investment and maintenance cost for the fixtures and control hardware.

• KIEAE Journal
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• v.8 no.4
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• pp.43-48
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• 2008

One of the most important factors in determining the quality of living environment is daylighting. Especially its influence in the psychological and biological life of human beings cannot be underestimated. Therefore, lots of researches have been given to develop a more efficient daylighting system. The sunlighting system, one of many developed systems, has been developed and applied in various ways. However, the high cost of sunlighting system has been the most difficult stumbling-block in making it commercial. However, as domestic apartment houses tend to be more luxury, life environment becomes a very important factor more than cost in building apartment house. Therefore, it would be possible to adopt sunlighting system in the non-window areas such as a restroom in an apartment house. This research is a preliminary work in order to measure a possibility of applying sunlighting system in an apartment house. In order to do so, I measure Sunlight Illuminance Ratio in various areas of apartment house. As a result, in case of a residential-commercial building, areas such as kitchen, restroom, and entrance are relatively weak-lighting areas. In case of a traditional apartment house, restroom and entrance are relatively weak-lighting areas. For that reason, a special lighting support is needed in these areas.

• Architectural research
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• v.1 no.1
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• pp.31-40
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• 1999

In this age of "Information", many people consider it a deterrent to information flow to provide a hierarchy with private rooms in a modern office layout. There are others, however, who insist that visual and acoustical privacy are more important than any other design factor in achieving higher productivity. The debate may never end, but the partitioned open plan, which is a new form of the vast open plan, has merits of each concept - open and closed layout. Consequently, office design has dramatically shifted to partitioned open planning, with shorter, temporary walls or partitions, originally intended for increasing privacy and diminishing hierarchy, yet still keeping flexibility in spatial organization. The introduction of low-level partitioned spaces in an office layout, however, produces a complicated lighting design problem. Obviously, accurately predicted daylighting performance data are needed not only for daylighting design but for artificial lighting system design. Scale models of 12 sets of unit partitioned spaces are constructed and extensive scale model measurements of both daylight and reflected sunlight have been performed within an artificial sky simulator. The prototype-building interior is modeled with different partition configurations, each of which is modeled using the different envelope geometry and exterior configurations, and then the variations in interior light levels are estimated. The result indicates that partitioned spaces employed in an open plan of modern offices still offer a large potential for daylighting and energy saving as well. Much of the savings may derive from the cumulative effect of reflected sunlight. Optimal design for building envelope geometry and exterior configuration promises additional savings.

• KIEAE Journal
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• v.8 no.1
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• pp.37-44
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• 2008

Though they have advantages in terms of aesthetic in modern architecture, however, rectangular-shaped towers causes being short of natural light due to deep interior space. There are compromised attempts to take advantages of each building shape selectively. As a result, we now witness the advent of Y-shaped, T-shaped, V-shaped and ㅈ-shaped buildings on the market. The mutative type of apartment houses usually faces southwest or southeast, which has lot of daylighting availability but anyhow, the proportion of the apartment houses which have a full south aspect. The need to verify the potential of daylighting in new building-block shapes exists. At the same time, the expansion of balcony area was legalized and thus, a visual buffer area does not exist any more. All-glass window wall on apartment houses without a balcony produces pretty harmful area with direct sunbeam. Recently, the refurbished version of conventional windows has been developed for the purposed of minimizing energy loss occurred around windows. This research initialized a series of research to deal with almost all on window wall for apartment houses. First of all, huge amount of already-designed examples of apartment houses have been analyzed in terms of floor plan, elevation, orientation and glazing materials.

• Journal of the Korean Solar Energy Society
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• v.25 no.2
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• pp.35-43
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• 2005

This study aims to evaluate the natural lighting performance in the sound barrier tunnel. Therefore, to evaluate the daylighting performance, the combinations of 3 tunnel roof types which are flat-roof-type(type A), slope-roof-type(type B), arch-roof-type(type C) and 3 window types which are side-window-type(type 1), one-window-roof type(type 2), two-window-roof type(type 3) are evaluated by experimenting small scaled models. In this 9 cases of experiment, illuminance levels of each case are analyzed and evaluated. The conclusion of this study is that slope-roof-type(B) and arch-roof-type(C) is preferable to flat-roof-type(A) and one-window-roof-type(B) and two-window-roof-type(C) is preferable to side-window-type(A) for daylighting in the sound barrier tunnel.

• Journal of the Korean Solar Energy Society
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• v.33 no.2
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• pp.56-63
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• 2013

Daylighting system is an alternative lighting system using daylight collecting device, light transformer and light diffuser. In this paper, we developed a daylighting system in which the collecting device composed by dual parabolic reflectors, the silica optical fiber adapted to the light transformer and light diffuser made of the polyglass square sheet. We have estimated the system efficiency and general color rendering index(Ra) of the developed system. The system efficiency measured to 23.8% and Ra was revealed as 95. Ra number of the developed system is bigger than the number(65) of the previous fresnel lens based sunlight collector.