• Wind and Structures
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• 제5권5호
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• pp.463-478
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• 2002

Lighting and traffic signal columns are mainly stressed by excitation due to natural, gusty wind. Such columns typically have a door opening about 60 cm above ground level for the connection of the buried cable with the column's electric system. When the columns around this notch are inadequately designed, vibrations due to gusty winds will produce considerable stress amplitudes in this area, which lead to fatigue cracks. To give a realistic basis for a reliable and economic design of lighting and traffic signal columns, a number of experimental and theoretical investigations have been made. The proposed design concept allows the life of such columns to be assessed with a satisfactory degree of accuracy.

• Wind and Structures
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• 제4권2호
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• pp.163-176
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• 2001

Two 12 m high tubular steel lighting columns have been instrumented to determine the wind-induced fatigue loading experienced by such columns. Each column supported a single luminaire mounted on a 0.5 m long bracket. One column was planted in soil, and the other bolted through a welded baseplate to a substantial concrete base. The columns were strain gauged just above the shoulder weld which connected the main shaft to the larger base tube. Forced vibration tests were undertaken to determine the natural frequencies and damping of the columns. Extensive recordings were made of response to winds with speeds from 4 m/s to 17 m/s. Selected records were analysed to obtain stress cycle counts and fatigue lives. Mean drag coefficients were also derived from the strain data to investigate experimentally the effect of Reynolds Number.

• 한국안전학회지
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• 제19권3호
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• pp.70-77
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• 2004

A Reasonable lighting should be provided for doing night work. All works far construction site can be exposed to potential hazard at night work The purpose of this study is to provide a standard of the lighting against accidents due to insufficient lighting at site. one pilot tea one at building work site, one at mad work site of it have been conducted for figuring out illumination change depending worker's activity direction, using lux checker to show it as numerical indication. The direction are changed with a range of 30, 60, 90, and 135 degree to be checked at site. Tests results show that $10\%\;and\;15\%$ of lighting could be decreased by changing the working direction of works at site. Therefore, steep slope place, cave work and backside of structural elements such as a column, deep beam should be considered for keeping sufficient and reasonable lighting. It is found that $50\%more$ illumination Lux needs f3r civil work than for building work.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2004년도 추계학술대회 논문집 전기물성,응용부문
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• pp.11-14
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• 2004

In this paper we report on development of our original mercury-less fluorescent lamps for general lighting. These new-type lamps have multi-pairs of electrodes to maintain multi-discharge paths and to keep positive column diffused state. The omission characteristics oft the lamps were investigated. These discharge lamps were operated by pulsed discharge. By using multi-pairs of electrodes for xenon pulsed discharge fluorescent lamps, higher intensity of luminance was obtained than the conventional type of lamps using single pair of electrodes. Recently this type of lamp achieved over $9000\;cd/m^2$ and 50 lm/W.

• 교육시설 논문지
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• 제21권2호
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• pp.33-39
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• 2014

In the case of low-rise buildings in seismic performance evaluation, lateral force resistance of the pillars affects the seismic performance of the building. Evaluation of the seismic performance of the column is determined by the holding performance is evaluated by comparing the shear strength and bending strength it was destroyed bylow intensity. In case of the school building, in order to install the large windows for ventilation and lighting of the partition walls are located between the pillars. The case of the pillars of these, shear failure occurs in the event of an earthquake is often, in the seismic performance evaluation, partition wall and the wall of the shim is evaluated ignoring, pillar of the general pillars If you have to calculate the results of the seismic performance distorted that are destroyed by bending behavior can be evaluated as often. Results of the study, when assessed by distinguishing the effective length of the column, it was found that when a seismic load is applied, it is possible to accurately predict the failure mode, reliable results of seismic performance evaluation of the school building.

• Structural Engineering and Mechanics
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• 제38권2호
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• pp.249-259
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• 2011

Band windows are commonly used in reinforced concrete structures for the purpose of ventilation and lighting. These applications shorten the lengths of the columns and, consequently, they are subject to higher shear forces as compared with those of hollow frames. Such short columns may cause some damages during earthquakes. Hence, these effects of short columns should be minimized by choosing the dimensions of the band windows properly in order to prevent serious damages in the structure. This can be achieved by taking into account the parameters that are crucial in causing short column effect. Hence, in this study, the effects of those parameters such as the widths and heights of the band windows, the number of bays and storeys within the frame, and the heights of storeys are examined. The effects of the parameters are analyzed using time history analysis. One of the important results of these analyses, is that, the widths of the band windows should be less than 60% of the clear span between the columns, whereas, their heights should be greater than 35% of the clear storey height in order to decrease the short column effects substantially during the design of the reinforced concrete structures.

• 전기학회논문지
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• 제63권12호
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• pp.1697-1703
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• 2014

In this paper, we propose an indoor RSSI (received signal strength indication)-based localization method that uses virtually overlapped visible light with an indoor LED lighting system. In our system, a photodiode (PD) measures the RSSI from LED lamps that blink in one row or column units. Subsequently, the RSSI is used to obtain the horizontal distances between the LED lamps and the receiver with the predetermined characteristics curve, R-D curve, that represents the relation between the RSSI and the horizontal distances. When the controlled LED lamps blink in one row or column units, the R-D curve at the border of the LED lamps is different because of the weak lighting, which results in the position sensing error of the receiver. The deviation of the optical power of each LED also causes the error. To solve these problems, we propose a method that overlaps the visible light through the numerical operation at the receiver side without any modification of the light source side. Our proposed method has been simulated in a room measuring $1.2{\times}1.2{\times}1.8m^3$ considering the effect of the error on the optical power of the LED. The simulation result shows that the proposed method eliminates the error condition with the R-D curve and achieves an average positioning error of 13.4 mm under the error rate 3% of the optical power.

• 한국지능시스템학회논문지
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• 제13권4호
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• pp.461-468
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• 2003

In a sequence of images obtained by surveillance cameras, facial regions appear very small and their colors change abruptly by lighting condition. This paper proposes a new face detection scheme, robust on complex background, small size, and lighting conditions. The proposed method is consisted of three processes. In the first step, the candidates for the face regions are selected using face color distribution and motion information. In the second stage, the non-face regions are removed using face color ratio, boundary ratio, and average of column-wise intensity variation in the candidates. The face regions containing eyes and mouth are segmented and classified, and then they are scored using their topological relations in the last step. To speed up and improve a performance the above process, a block based image segmentation technique is used. The experiments have shown that the proposed algorithm detects faced regions with more than 91% of accuracy and less than 4.3% of false alarm rate.

• 생명과학회지
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• 제15권3호
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• pp.468-473
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• 2005

여수연안은 어류 치사성 유해적조생물인 C. polykrikoides 적조가 매년 발생되는 해역일 뿐만 아니라 섬진강으로부터 담수유입이 돌산을 중심으로 많은 영향을 받고 있다. 담수유입에 따른 염분도 변화가 C. polykrikoides의 수직이동에 영향을 미칠 수 있는 지를 조사했다. 실험장치는 60l들이 아크릴 수조에 일반해수와 담수와 해수를 혼합시킨 시험구를 설정하여 C.polykrikoides의 수직부상 속도와 DNA/RNA함량 비교를 하였다. 실험은 5일 동안 시행했다. 실험개시로부터 종료시까지 시험구의 경우 상층부위에서는 염분이 20으로 나타난 반면에, 하층은 30 정도로 유지되었다. 그러나 용존산소와 pH 변화는 시험구와 대조구 모두 비슷한 양상을 보였다. 또한 chlorophyll a도 수조의 하층보다 상층에 높은 수치를 보였다. 24시간동안 C. polykrikoides 상$\cdot$하층 이동을 조사한 결과 점등이 되는 순간 시험구는 대조구에 비하여 월등히 높은 상승을 보였으나, 시간이 경과함에 따라 그 차이는 적었다. 소등이 되는 동안은 점등에 비하여 상$\cdot$하층 현저한 차이를 볼 수 없고 대부분 균일하게 분포하는 양상을 보였다. 또한 실험 종료시나 24시간 주 $\cdot$야간 수직이동 시 대조구에 비하여 시험구에 분포하고 있는 C. polykrikoides의 DNA 및 RNA 변화폭이 높았다 이 실험을 통하여 담수유입은 C. polykrikoides 세포에 많은 영향을 미칠 수 있을 것으로 보이며, 특히 신속한 수직상승으로 인하여 여기에 대한 C. polykrikoides의 모니터링이 절실히 요구되는 바이다.

• 한국실내디자인학회논문집
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• 제18권5호
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• pp.156-163
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• 2009

Retail space itself could be one of the marketing strategies, through creating space, and communicating brand identity. Especially for innovative products, such as mobile technology products, store is not just to sell products but to provide experiences so that users can fudge usefulness of products and reduce uncertainties to adopt the products. The purpose of this study is to investigate how environmental features and physical artifacts contribute to promote experiences of innovative products in stores and how physical environment help to establish brand identity. For this study, site visits, observation, and literature review were conducted. For case studies, three retail spaces (Apple, Iriver, Sony) and one service space(TTL) were selected. Compared to the service space, three retail spaces have more transparent and open store front design characteristics. For the experiences of shoppers, products displayed in a radial shape, round shape, column shape, and around peripherals of the stores. A service oriented space, TTL zone is differentiated from three retail spaces in terms of layout, store front design, and experience areas. Compared to the traditional stores selling innovative products, the case stores showed more warm atmosphere using various shape, wood materials, lighting fixtures and furniture.