Recycled aggregate is a solution to reduce construction waste and to be environmentally friendly, but concrete using it has various disadvantages in terms of structure. Therefore, the interaction effect of the two materials can be expected by filling the cyclic aggregate concrete in the CFT column. Eighteen specimens were constructed to confirm the compressive behavior of RCFT (Recylced Concrete Filled Tube) columns, which can be applied to real buildings by making high strength concrete with recycled aggregate. Variable is the shape and thickness of steel pipe, concrete strength and mixing ratio, and coarse aggregate and fine aggregate are all used as recycled aggregate. A total of three recycled aggregate concrete preformulations were used to find the optimal mixing ratio and the compressive behavior was analyzed through the load - displacement curves of RCFT columns.

This study develops numerical model of mega composite columns in fire and investigates the residual areas using 500℃ isotherm method and residual capacity of mega composite columns after 3 hours. In order to perform heat transfer analysis, thermal properties of steels and concrete were adopted from Eurocodes. In addition to, the temperature distributions of composite columns with respect to fire tests were compared with numerical analysis results. As a result, residual capacity of mega composite column with 1m width remained more than 45%. The residual capacity of mega composite column was only increased to 2.3∼2.6% with the use of additional rebars.

해양환경의 극한 환경조건에 노출 된 고정식 및 부유식 해양구조물의 안전성과 설계비용 효율성에 있어서 파랑-구조물 상 호작용의 정확한 예측은 중요하다. 본 연구에서는 규칙파 중 원형 기둥에 대한 파랑-구조물 상호작용을 해석하였다. 3차원 이상유동 (two-phase flow)을 해석하기 위해 오픈소스 전산유체역학 라이브러리인 오픈폼을 사용하였다. 4개의 원형기둥이 정사각형 배열을 이루 고 있을 때 규칙파의 입사각도에 따른 상호작용을 해석하였다. 원형 기둥 구조물에서의 wave run-up을 입사파의 기울기에 따라 비교하 였다. 원형 기둥과 입사파의 상호작용으로 인해 원형 기둥 사이에 높은 파가 생성되는 것을 확인하였다. 본 해석 결과는 구조물과 입 사파의 상호작용에 의한 air gap에 대한 연구의 기초자료로 활용될 것으로 기대된다.

최근 경제 교육에 대한 관심이 높아져가고 있지만 아직까지 학교 현장에서는 경제 교육 프로그램들이 충분하게 활용되지 못하고 있는 실정이다. 이러한 문제에 대한 해결 방안을 찾기 위해 한진수가 제시한 ‘네모 피자 만들기’ 프로그램을 수정·보완 하여 실제 현장에 적용한 뒤 그 결과를 분석하였다. 이 활동은 총 세 라운드로 구성되어있다. 1라운드에서 학생들은 네모 피자 가게에 서 근무하는 직원이 되어 여러 색의 종이를 이용하여 네모 피자를 만들게 된다. 이 때 가위는 사용하지 못하도록 한다. 2라운드에서는 1라운드와 같은 활동을 반복하 되, 가위를 사용할 수 있도록 한다. 본 연구에서 새롭게 추가된 3라운드에서는 그 동안의 노동으로 벌어둔 가상의 돈으로 가위라는 자본에 직접 투자를 하여 작업을 할 수 있도록 한다. 기존에 개발된 ‘네모 피자 만들기’ 프로그램은 초등학교 고학년을 대상으로 개발되 었기 때문에, 이를 4학년 학생들에게 적용하기 위해 작업 수준을 다소 낮추고 수업 내용도 재구성하였다. 그리고 활동 전과 활동 후에 각각 경제 이해력 및 태도에 관 한 검사를 실시한 결과 학생들의 경제 이해력과 경제에 대한 의사결정 태도가 유의 미하게 향상되었음을 확인할 수 있었다.

As an alternative to conventional explosive methods for demolition of concrete structures and rocks, the use of non-explosive demolition agents can be considered to reduce noise, vibration, and dust emissions during the demolition process. In this study, we conduct finite element analysis for crack initiation and propagation caused by the expansion of non-explosive demolition agents in square concrete structures. The predicted crack patterns are compared with the experimental results in the literature. The minimum values of the required expansion pressure of non-explosive demolition agents are also estimated, which depend upon the arrangement of non-explosive demolition agents and empty holes. Furthermore, we investigate the effect of empty holes on the fragmentation of concrete structures, and discuss the effective arrangement of non-explosive demolition agents and empty holes for fragmentation improvement.

A very unique case is found in the architectural remains related to the north and south square-platform at the lecture hall site of Hwangnyongsa, that of Anyangsa, and the estimated lecture hall site of Beopsusa as they are not observed in the other lecture halls. The platform has been discovered at only those three Buddhist temples from Goryeo, and its case has not been found in ancient Buddhist temples of China and Japan. This study thus set out to investigate the north and south square-platform at lecture hall sites by examining in details its architectural remains at the three Buddhist temples and reviewing the Buddhist literature about the lecture halls of ancient Buddhist temples. Based on the findings, it was estimated that the architectural remains of north and south square-platform at the lecture hall sites of Buddhist temples were those of platform for Buddhist sermons or those of high chair platform. While the north square-platform involved the remains of north high chair for the Lecturer that gave lectures on the Buddhist scriptures, the south one did those of south high chair for the Reader who recited the Buddhist scriptures.

본 연구는 두꺼운 난류경계층 내에 놓인 구조물의 높이와 방위각이 달라짐에 따라서 나타나는 구조물 주위의 유동특성을 파악하고자 하였다. 구조물 주위의 유동특성을 파악하기 위해 대기경계층 풍동실험을 수행하었다. 구조물의 높이는 3가지로 변화시켰으며, 방위각은 0∼90°까지 변화시켰다. 풍동실험의 레이놀즈수는 각 구조물 높이에 따라 다르게 나타나며 각각의 레이놀즈수는 10.4×104(H1), 29.4×104(H2), 43.2×104(H3) 이다. 연구결과로서 높이와 방위각이 변화함에 따라 모서리에서 발생하는 박리현상이 변화하고 이는 구조물의 표면압력과 섭동압력에 상당한 영향을 끼치는 것을 확인할 수 있었다.

The study aims to discuss the relation between square-shaped Chinese Characters and the attitudes of life. There are six structures of Chinese Characters, which influence six kinds of attitudes of life of Chinese people. First, the right-and-left structure ( , ex.好) and the vertical structure ( , ex. 惡) demand symmetry and balance, which shows the love of equitable attitude of Chinese people. Second, the axis positioning of Chinese Characters, shows that Chinese people persist in moderation. Third, surrounding structures encourage Chinese people to be introverted and humble. Fourth, the Pyramid-shaped structures (ex.品) show the respect for seriousness and solemnity. Fifth, the components combined in layer strengthen Chinese people’s values of order and group. Last, the straight strokes and vertical writing reflects Chinese people respect for decency and uprightness. The six structures and the six attitudes influence and accomplish one another. This research is also hoped to inspire different thoughts on the cultural aspect of Chinese Characters. Most of all, the knowledge can lead us to know learn more about the Kaishu’s value in both the ancient and modern times.

The basic design is a plan to create Dongdaegu Station as part of the square in front of the Dongdaegu Station expansion project. This includes a landscaping plan in connection with a synaptic complex transit center development plan. KTX Dongdaegu Station Square is in the center of the complex, and transit passengers are transferred to the best routes to the station extension, with a variety of KTX Gyeongbu transportation routes planned. Located in the heart of the city, the square should be expanded based on the use of past railway stations to function as a city square. The basic design for the KTX Dongdaegu Station Square involves a sense of symbolism, place, public space, and environmental consciousness. First, it highlights the symbolism of Daegu’s identity in planning the concept, and it establishes an eco-friendly nature, taking into consideration the environmental characteristics of Daegu. Second, planning the space from past-oriented public transport secures the functions and features of the pedestrian plaza in the urban context. In particular, it plans to incorporate environmentally friendly low-carbon planning and purification forest plans. Distant, middle, and close-range views are established in accordance with the landscape plan, including three forest conditions, taking into account the nature of the three-dimensional space and establishing a planting plan. Third, a packaged integration plan is established for the enclosure, decoration, and directional limitation of the transportation square, which is located in the city forest and grassy yard between the square and the main road to ensure the direction and connection with the facilities and the symbolic sculptures. This plan can serve as a new model for the planning of railway station squares, turning them into cultural complexes in the public space of the city.

Through this study, velocity distribution characteristics of exit section and downstream straight length of square sectional 180° and 90° curved ducts were numerically analyzed with RSM (Reynolds Stress Model) by changing various flow parameters such as air velocity, surface roughness and hydraulic diameter etc. As a result of it, the maximum velocity profiles according to air velocity in 180° and 90° curved ducts were indicated at Y/D=0.8 and X/D=0.7 region. Also, the efficient measuring location in bended duct downstream was able to suggest when the most stable straight duct length in flow deviations were indicated at L/D=30 and L/D=10 region, and the standard deviation characteristics according to hydraulic diameter were mostly indicated at L/D=15∼30 and L/D=10 region considering minimum deviations in the same velocity condition.

Based on the reference achievement scholars before, combined with the actual survey results on Nom Tay documents currently stored in Institute of Sino-Nom Studies, conducted article comparing other cases face each other and are similar in structure between the written word: Nom of the Kinh and Tay ethnic group in Vietnam with the letter of the Zhuang ethnic blocks (Guangxi, China). This indicates that, basically 3 types of this writing there are a lot of similarities in terms of composition, the differences are very small and specific characteristics. This sector should be studied in depth and hopefully more will have interesting results in the future.

In this study, we have modeled the rear side of the HVAC diffuser with square prism and tried to investigate the influence of a wake flow by PIV and a numerical analysis using computational fluid dynamics based on steady-state Navier-Stokes equation and standard k-ε model. A commercial CFD program, FLUENT, is used on the analysis. The wake is generated by a square prism, which is installed at the divergent flow. The results show that a fluid are distributed up and down directions of prism, and the recirculation regions are decreased.

In physical engineering, the turbulent flow on the surface roughness is very important. The roughness of the surface changed the distance of the interval. The roughness coefficient occurred with increasing turbulence intensities was stronger. The turbulence intensity away from the roughness in the shape was zero. The variation of turbulence intensity at the experimental flow conditions change was not affected.

The present study is aimed to reconsider the time of installation and the purpose of the square footstone located at the center of the wooden pagoda in Hwangnyongsa Temple, based on related precedent studies. Precedent studies are divided into two streams of assertions: one is that the square footstone was to support the major pillars at the time of building and the other is that it was installed to store Buddhist reliquaries inside the central foundation stone after the wood pagoda burnt down in the Invasion of Mongol. Summarizing the grounds with which the precedent studies support their assertions, they are the relation with Gaseopbul Yeonjwaseok, the emerging time of the square footstone, repairing work at the level of reconstruction, additional enshrinement of general Buddhist reliquaries and so on. The present study reviewed the key grounds suggested in the previous studies regarding the square footstone. First, it was determined that the square footstone has nothing to do with Gaseopbul Yeonjwaseok, after looking into the timings of appearance, condition and shape in literatures. Rather, it was assumed that Gaseopbul Yeonjwaseok resembles a stone column. Next, the square footstone is assumed to be installed after the 4th year of King Kwangjong’s rule because the wood pagoda was lost in fire in the 4th year of Kwangjong’s rule and it had been left alone for 68 years until the repair work finished in the 13th year of King Hyunjong. It is assumed that repair works at the level of reconstruction had been twice in total, say, once during King Kyungmun and Hyunjong, respectively. Next, looking into the establishment of the general Buddhist reliquaries and the repair work during King Kyungmun, it was not common then to enshrine additional Buddhist reliquaries when repair work progressed and so there was not an additional enshrinement of Buddhist reliquaries after King Kyungmun. However, it is hard to decide that there was no repair work at the level of reconstruction at that time. Last, we can find a similar case to the square footstone of the wood pagoda in Hwangnyongsa Temple in the copper pagoda in Japanese Yaksasa Temple. In conclusion, it is assumed that the wooden pagoda in Hwangnyongsa Temple was lost to the fire in the 4th year of King Kwangjong’s rule and thus the square footstone had been used as Jinho stone to protect Buddhist reliquaries and used as a propping stone for the major pillars after King Hyungjong.

So far, square concrete filled tubular(CFT) columns have been used in a limited width thickness ratio. The reason is that local buckling occurs in steel tube easily. Once the local buckling occurs, the confinement effect of steel tube on concrete disappears. In this study, we developed welded built-up square steel tube with reinforcement which are placed at the center of the tube width acts as an anchor. 3 specimens of slender welded built-up square CFT columns and 3 specimens of slender welded built-up square steel tube columns were manufactured with parameters of width(B) of steel tube, width thickness ratio(B/t). we conducted a experimental test on the 6 specimens under eccentric load, and evaluated the structural resistance and behavior of 6 specimens.

CFST columns are structurally superior because the concrete inside the steel tubes prevents local buckling at the tubes and the tubes confine the concrete. And, the thickness of steel tube in CFST column has been thinner with development of high-strengh steel. The thinner the steel tube of a square CFST column is, the more local buckling is likely to occur. For this reason, we developed welded built-up square steel tube with stiffeners which are placed at the center of the tube width acts as an anchor. In this study, we conduct experimental test for three specimens of the 4m long span welded built-up square CFT column with parameters of L/D and D/t. And, the test results were compared with the analysis results by M-ϕ-P Program.