• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.17 no.6
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• pp.16-22
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• 2003

The purpose of this study was to provide visual evaluation data in a workstation space when different lighting types were applied. For the performance evaluation, Radiance program was used for simulations, and the mock-up room(15.0x11.6x3m) was used for the actual test. The results of this study were as follows; 1) When the inidirect lighting simulation data using Radiance was compared with the actual data in a small workstation space, there was a 6.5% difference. Therefore, Radiance program was proved to be useful for the evaluation of lighting performance. 2) Higher light levels (higher light ratio (%)) were recorded in the straddled layout and lower light levels (lower light ratio (%)) were recorded in the centered layout condition in most cases. 3) Also, the results show that the indirect luminaires and the straddled layouts provide higher uniformity, whereas the direct luminaires and the centered layouts have lower uniformity.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.36 no.3
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• pp.155-163
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• 2023

Real-time monitoring technology is critical for ensuring the safety and reliability of nuclear power plant structures. However, the current seismic monitoring system has limited system identification capabilities such as modal parameter estimation. To obtain global behavior data and dynamic characteristics, multiple sensors must be optimally placed. Although several studies on optimal sensor placement have been conducted, they have primarily focused on civil and mechanical structures. Nuclear power plant structures require robust signals, even at low signal-to-noise ratios, and the robustness of each mode must be assessed separately. This is because the mode contributions of nuclear power plant containment buildings are concentrated in low-order modes. Therefore, this study proposes an optimal sensor placement methodology that can evaluate robustness against noise and the effects of each mode. Indicators, such as auto modal assurance criterion (MAC), cross MAC, and mode shape distribution by node were analyzed, and the suitability of the methodology was verified through numerical analysis.

• Journal of Environmental Impact Assessment
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• v.23 no.6
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• pp.477-491
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• 2014

The purpose of this study is to develop urban planning for mitigating thermal comfort by analyzing the relationship between various physical environmental factors and radiation fluxes focused on urban areas of Changwon city, Gyeongsangnam-do. Physical environmental factors were analyzed by sky view factor (SVF), land cover and land use types using GIS program. Radiation fluxes were measured upward and downward in solar and terrestrial radiation by mobile measurement during 3 days (2 daytime and 1 nighttime) in summer season. SVF is high in urban park less around buildings. High dense building sites were low. Downward solar radiation fluxes were the highest about $700W/m^2$ at daytime, and decreased in spatial type arranged dense buildings. Upward solar and terrestrial radiations was affected by land cover types that have thermal features such as reflectivity, emissivity, and heat capacity. Therefore, urban space needs appropriate planning with building arrangement, green walls and land cover replacement for mitigating thermal comfort in urban area.

• Journal of The Korean Society of Grassland and Forage Science
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• v.26 no.4
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• pp.285-292
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• 2006

This study was conducted to evaluate the dry matter yield and forage quality of Kenaf in relation to planting density and growing days in Cheorwon area from 20 May to 12 September in 2005. The experiment was laid out in a split plot design with three replications. The main plots consisted of planting density and growing days with three cultivars of Kenaf as sub-plots; Bowling, Everglade and Tainung. The results obtained were summarized as follows. The dry matter yield increased until 92 days after planting at $10{\times}10cm^2$ planting density, but decreased after the day. The dry matter yield increased with maturity in all three cultivars, especially Dowling showed the highest dry matter yield at each harvest time. The Crude Protein (CP) contents of all three cultivars decreased with maturity. Especially, the decrease in the CP contents was greater in the early stage than in the late stage. The planting density did not affect the CP contents, even though they are little higher in $10{\times}20cm^2$ planting density. The higher CP contents were obseued in Dowling, which is not significant. No difference in the Neutral detergent fiber (NDF) and Acid detergent fiber (ADF) contents was observed in the planting density and cultivar, although the increasing tendency was found with maturity. These results suggest that Kenaf can be a good potential forage crop in the northern area of Korea, especially Dowling showed the great dry matter yield and forage quality when harvested on Day 104 at $10{\times}20cm^2$ planting density.

• Journal of the Korean Institute of Educational Facilities
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• v.19 no.1
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• pp.37-44
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• 2012

This study developed an algorithm to predict the most efficient evacuation protocol in an elementary school that has an irregular type of architectural planning. The assumption of this study takes a stand point that today's elementary schools are designed in unusual and irregular floor type and, therefore, past architect's knowledge regarding efficient evacuation will no longer effective to save lives. In this regard, this study applied an algorithm that is especially designed to find appropriate locations in general in the field of industrial engineering, which has been proven for many decades. Furthermore, this study not only adapted an engineering model but also conversed to examine spatial relationship and added the concept of group evacuation, which will delay the whole evacuation process, in the tested algorithm to make it more architectural. Consequently, this study compared its outcome with an existing elementary school and questioned its effectiveness in evacuation process based on the algorithm.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2007.05a
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• pp.70-73
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• 2007

생활수준의 향상으로 인하여 조명 및 디스플레이 제품을 이용하여 건물 및 건축물에 대하여 장식을 하는 것이 일반화 되어가고 있다. 본 연구에서는 옥외 및 옥내에 사인물로 사용되어지고 있으며 설치가 간편한 디스플레이 조명기기인 LED Tile을 개발하여 옥내 및 옥외용 디스플레이 조명 시장의 시장성 확보하기 위하여, 광학설계를 통한 고휘도 LED의 선정 및 배치, 케이스 설계를 실시하고 LED모듈에 AC 220V 전원을 직접 인가할 수 있으며 효율이 높고 최적화된 구동회로를 설계하였다. 또한 One Chip 마이크로컨트롤러를 사용하여 RGB LED의 광색가변 및 점멸 제어회로를 설계하고, LED 모듈간에 2개의 제어선만을 연결하여 다양하고 다이나믹한 패턴 동작(점멸, 광색가변)이 가능하도록 펌웨어를 설계하였다. 그 결과 설계된 LED Tile은 전체 크기가 $D130{\times}W130{\times}H50mm$로 매우 컴팩트하고 LED 배치 및 광학설계를 통하여 최대광도 60cd를 실현하였으며, LED Tile의 동작개수에 관계없이 설치가 간단하며 10개 이상의 디스플레이 패턴 제어가 가능하였다.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2018.05a
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• pp.39-40
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• 2018

The goal of site layout planning(SLP) is to maximize the productivity and efficiency of the construction by reducing travel distance and material handling cost and manpower. However, SLPs are static layout schemes, which cannot be reorganized during the construction process to correspond with errors, phase transition, changing working environments on the site. To solve this problem, researches on dynamic site layout planning(DSLP) are emerging. This preliminary study clarifies characteristics of temporary facility's variables to develop the vertical DSLP algorithm of high-rise building construction.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2011.05a
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• pp.171-172
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• 2011

Formwork accounts for a large proportion of the framework in high-rise construction projects in terms of the duration and cost. Especially, slab formwork has a significant influence on these factors. However, the current selection of formwork method in general contractors depends on the decisions of few experienced engineers, and layout planning of the formwork in specialty contractors requires lots of time by different floor types. As a preliminary study for developing an optimum layout model in slab formwork of high-rise building construction, this study proposes the process of the optimum layout model and determines a fitness function for use of the genetic algorithm aimed at table formwork.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2013.05a
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• pp.171-172
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• 2013

An operation planning of lift car is crucial in tall building construction especially it's arrangement plans, because it is related with transportation distance of finishing materials affecting construction productivity. Since tall building construction, composed of complicating and huge plane have complex traffic lines of finishing materials, to determine the position of lift car empirically or intuitively has limits. Therefore this paper suggest an optimum layout model of lift car minimizing the transportation distance both at site-level and floor-level using Graph theory and Dijkstra algorithm.

• Journal of the Institute of Electronics Engineers of Korea CI
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• v.44 no.1
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• pp.41-48
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• 2007

In this paper, we propose an optimal placement of sensor nodes with 2.4GHz wireless channel characteristics. The proposed method determines optimal transmission range based on log-normal path loss model, and optimal number of sensor nodes calculating the density of sensor nodes. For the lossless data transmission, we search the optimal locations with self-organizing feature maps(SOM) using transmission range, and number of sensor nodes. We demonstrate that optimal transmission range is 20m, and optimal number of sensor nodes is 8. We performed simulations on the searching for optimal locations and confirmed the link condition of sensor nodes.