• Nuclear Engineering and Technology
• /
• 제54권10호
• /
• pp.3766-3777
• /
• 2022

It is essential to ensure the safety of spent nuclear fuel (SNF) transport cask in drop situation that is included in transport accident scenarios. The safety of the drop situation is affected by the impact absorption performance of impact limiters. Therefore, when designing an impact limiter, the uncertainty in the material properties that affect the impact absorption performance must be considered. In this study, the material properties of the wood inside the impact limiter were selected as the variables for a parametric study. The sensitivity analysis of the drop response of the SNF transport cask with impact limiter was performed. The minimum wood strength required to prevent a direct collision between the cask and floor was derived from the analysis results. In addition, the plastic strain response was analyzed and strain-based evaluation was performed. Based on this result, the critical values of wood properties that change the impact dynamic characteristics were investigated. Finally, the optimal material properties of wood were obtained to secure the structural safety of the SNF transport cask. The results of this study can contribute to the development of SNF transport cask, thereby ensuring safety in transport accident conditions.

• 설비공학논문집
• /
• 제17권12호
• /
• pp.1123-1131
• /
• 2005

The floor material is known as the most influential emission source of the residential building, because most floor material is made of wood compound and adhesive like a plywood flooring. Moreover, floor heating system keeps the inside temperature of the material high. As the emission of hazardous chemical compound from the construction material is influenced by many factors, it is necessary to analyze the emission characteristics of the floor material to improve IAQ. In this study, numerical analysis is performed to investigate the emission characteristics of the floor material affected by several factors such as temperature, air exchange rate, initial concentration, and internal diffusion coefficient. A simulation program is also written based on the mass transfer theory. The simulation results show that there is some level of difference on the TVOC concentration when each of the factors is variable.

• 한국농촌건축학회논문집
• /
• 제4권1호
• /
• pp.29-36
• /
• 2002

The characteristics of the rural dwelling houses of the Korean communities were investigated and analyzed to understand their rural dwelling culture in east-northern China. This research was done by the field survey of rural village, Longshancun, Yanbian. The structures of their houses are changed into the brick houses from the earthen houses with wood frame. The floor plans are changed into Dual-bay-type of Divided-space from Single-bay-type of Hollistic-space, the largest ratio at present, and the numbers of space are increased. In the view of total outline, their dwelling houses are based to those of east-northern Korea and are sustained to the vernacular dwelling styles(ex : floor heating, ondol, and sit-down), and are adapted to the geography and climate of Yanbian and accepted to the culture of other communities(ex : indoor-kitchen, indoor-removing-shoes).

• 한국실내디자인학회논문집
• /
• 제27권2호
• /
• pp.3-11
• /
• 2018

This study aims to investigate whether there is intensionally changing eye - gaze on the cafe space images with floor finishing materials. In the Yarbus' experiment, he argued that changing information that an observer is asked to obtain from an image changes pattern of eye movements. Based on the scan path evidence, this research have questions as (1) the difference of visual attention on finishing floor material stimulus, (2) visual attention of initial activity time and type of movement paths on AOIs, and (3) visual relation floor area with another AOIs. Eye movements were recorded with the SMI REDn Scientific, which sampled eye position at 30Hz and lasted 2 minutes(120s). Although viewing was binocular, only the right eye was tracked. Of the 66 observers(mean age 22 years, standard deviation: ${\pm}1.82$) who participated in the experiment done by the four point calibration and validation procedures at the beginning tasks. Analyzing qualitative data from the number of fixation and duration on AOIs divided into four parts (AOI I-Floor, AOI II-Wall, AOI III-Ceiling, and AOI IV-Counter) in the stimulus. The results from this experiment analyzed as follows. First, it was significant in the difference of the average number of AOIs fixation times observed for the spatial image using the wood tile flooring material and the polishing tile. The wood tile flooring of stimulus had higher fixation number on AOI-II, AOI-III, and AOI-IV than the polishing tile. On seeing AOI-I was higher attention in the polishing tile stimulus. Second, the observers examined AOI-II intensively in both stimuli. However, the visual intensity was also followed by on the AOI-IV and AOI-I in the wood tile flooring stimulus, and on AOI-I, AO-IV in the polishing tile. Third, visual attention data on each AOIs have divided into the time range of "5 sec" for both images. In the wood tile stimulus, the horizontal movement path followed by AOI-II, AOI-IV, and AOI-II. In the polished tile stimulus, the movement path followed by moving vertically to AOI-II, AOI-I, and AOI-II. This study approached meaningfully and found out the characteristics of visual attention, according to the different intentions of visual attention, the relationship pathways of visual mechanism appeared and also activated by eye-tracking experiments.

• 보존과학회지
• /
• 제35권1호
• /
• pp.61-70
• /
• 2019

In this study, a scientific survey on the material of the mother-of-pearl floor mirror was conducted and conservation treatment processes were introduced. The survey results showed that the mother-of-pearl floor mirror in Daejojeon Hall of Changdeokgung is made of Dalbergia spp., and repair work seems to be done later with shorea spp. FT-IR analysis results showed that the varnishing is similar to the spectrum of lacquer. The metal wheels and metal line decorations set with mother-of-pearl were found to be made of brass based on XRF analysis, and the ingredient ratio showed that these were made in modern times. Foreign materials were stuck on the surface of the mother-of-pearl floor mirror before conservation treatment, which was in a structurally unstable condition owing to some missing submaterials. Conservation treatment was conducted on the damaged area to restore the mirror to its original appearance by using the same species of wood determined from the data obtained through the scientific survey.

• Journal of the Korean Wood Science and Technology
• /
• 제43권6호
• /
• pp.884-889
• /
• 2015

구조용 부재의 단열성능에 대한 적절한 평가와 냉난방에너지에 대한 합리적 제어는 건물의 에너지효율을 향상시키기 위하여 매우 중요하다. 한국의 일반적인 주택 난방방식은 바닥난방이다. 이와 같은 복사난방방식은 국내의 지정학적인 조건 또는 기후에 적합할 뿐만 아니라 온열감에 따른 정서적 안정감을 준다는 장점을 가진다. 국내의 바닥난방시스템을 적용하여, 목조공간과 콘크리트조 공간을 대상으로 축소모형을 제작하였다. 천장은 스티로폼으로 단열하고 벽과 바닥은 각각 합판과 콘크리트로 구성하였다. 바닥에는 난방필름을 부착하였다. 바닥난방에 따른 실내의 온도분포는 열전대로 측정하였고, 벽체 표면의 온도는 적외선 열화상 카메라로 측정하였다. 목조주택의 에너지효율 향상을 위한 데이터베이스 구축을 위해 축소모형의 단열성능을 평가하였다. 다양한 벽체와 바닥구성을 지닌 모형들의 단열성능평가 자료는 실제 주택의 열환경 분석시 참고기준으로 이용될 수 있을 것으로 기대된다.

• Structural Engineering and Mechanics
• /
• 제78권3호
• /
• pp.319-332
• /
• 2021

The wood-concrete composite is an interesting solution in the field of Civil Engineering to create high performance bending elements for bridges, as well as in the building construction for the design of wood concrete floor systems. The authors of this paper has been working for the past few years on the development of the bonding process as applied to wood-concrete composite structures. Contrary to conventional joining connectors, this assembling technique does ensure an almost perfect connection between wood and concrete. This paper presents a careful theoretical investigation into interfacial stresses at the level of the two interfaces in composite wooden beam- reinforced concrete slab strengthened by external bonding of prestressed composite plate under a uniformly distributed load. The model is based on equilibrium and deformations compatibility requirements in all parts of the strengthened composite beam, i.e., the wooden beam, RC slab, the CFRP plate and the adhesive layer. The theoretical predictions are compared with other existing solutions. This research is helpful for the understanding on mechanical behaviour of the interface and design of the CFRP- wooden-concrete hybrid structures.

• 한국주거학회논문집
• /
• 제18권2호
• /
• pp.65-74
• /
• 2007

The study analyzes the remodeling characteristics of the four different types of secondary kitchens in apartment house based on their floor plans. The secondary kitchens are categorized into side placement, back placement, back placement with extensions on both sides, and back placement with an extension on a single side. The twelve apartment complexes in Ulsan were selected so that they may all consist each of the four types, and answered the survey. The classified traits of secondary kitchen were examined based on the characteristics of floor plan and remodeling. Side placement and back placement with extensions on both sides mostly used glass hinged doors. Back placement and back placement with a single side extension used glass sliding doors. It was found that the majority of the floor materials consisted of both wood and tiles, except for side placements, where only tiles were used. The sizes of the back placements with both and single side extensions were the largest. The side and back placements were rarely renovated, however, back placements with both and single side extensions went through massive remodeling.

• Journal of the Korean Wood Science and Technology
• /
• 제42권6호
• /
• pp.691-699
• /
• 2014

용융점이 $138^{\circ}C$인 Bi-Sn 혼합합금 주입방법을 이용한 용융합금주입목재복합체의 제조를 통해 목재의 단점인 치수 안정성과 내구성의 개선을 하고자 3가지 주요 침 활엽수 수종의 수종별 최적주입조건을 구명하고, 주입에 따른 금속주입목재복합체의 중량증가율, 열전도도, 전기저항 등의 물리적 성질과 기계적 성질을 실험하여 다음과 같은 결과를 얻었다. 1. 금속주입목재의 최적처리 조건은 $185^{\circ}C$, 진공시간 10분 조건하에서 radiata pine의 경우 $10kgf/cm^2$ 가압시간 2분 30초, red oak는 $30kgf/cm^2$, 가압시간 10분, white oak는 $50kgf/cm^2$, 가압시간 10분에서 최적의 주입조건을 나타냈다. 2. 금속주입목재복합체의 외관적 특징은 전체적으로 재색은 회백색을 나타냈으며, 목재의 무늬를 그대로 유지하고 있다. 3. 침엽수 수종인 radiata pine은 저온용융합금주입처리로 인해 중량증가율은 12배, 밀도는 $6.13g/cm^3$으로 15배나 증가하였으나, 인테리어용으로 주로 사용되는 red oak와 white oak 등의 활엽수의 경우 목재해부학적 특성으로 의해 radiata pine보다는 낮은 5~6배의 밀도증가율을 나타냈다. 4. 주입된 목재는 침 활엽수 모두 금속주입으로 인해 수분흡수율과 두께팽윤율이 현저히 감소하였고, 매우 높은 치수 안정성을 나타냈으며, 금속주입목재복합체의 휨강도, 휨영계수, 경도 및 전기전도도와 열전도도 등도 무처리목재보다 매우 크게 향상되었다.

• Current Optics and Photonics
• /
• 제5권3호
• /
• pp.298-305
• /
• 2021

Modern distance sensing methods employ various measurement principles, including triangulation, time-of-flight, confocal, interferometric and frequency comb. Among them, the triangulation method, with a laser light source and an image sensor, is widely used in low-cost applications. We developed an omnidirectional two-dimensional (2D) distance sensor based on the triangulation principle for indoor floor mapping applications. The sensor has a range of 150-1500 mm with a relative resolution better than 4% over the range and 1% at 1 meter distance. It rotationally scans a compact one-dimensional (1D) distance sensor, composed of a near infrared (NIR) laser diode, a folding mirror, an imaging lens, and an image detector. We designed the sensor layout and configuration to satisfy the required measurement range and resolution, selecting easily available components in a special effort to reduce cost. We built a prototype and tested it with seven representative indoor wall specimens (white wallpaper, gray wallpaper, black wallpaper, furniture wood, black leather, brown leather, and white plastic) in a typical indoor illuminated condition, 200 lux, on a floor under ceiling mounted fluorescent lamps. We confirmed the proposed sensor provided reliable distance reading of all the specimens over the required measurement range (150-1500 mm) with a measurement resolution of 4% overall and 1% at 1 meter, regardless of illumination conditions.