PURPOSES : In this study, the thermal conductivity properties and mechanical performance of a thermally conductive asphalt mixture that can be applied to increase the efficiency of deicing asphalt pavements are evaluated. METHODS : Graphite powder and carbon fiber, which are inexpensive carbon materials, were added to the asphalt mixture to its conductivity. To determine the optimal mixing ratio of the carbon materials, the dispersibility, thermal conductivity, and performance of the conductive asphalt mixture were evaluated. The performance of the mixture was evaluated in terms of its volume characteristics, Marshall stability, dynamic modulus, indirect tensile strength (IDT), and wheel-tracking tests. RESULTS : The thermal conductivity of the asphalt mixture containing 2% graphite is 1.81 W/mK, which is approximately twice (0.94 W/mK) that of a general asphalt mixture. Meanwhile, the graphite-added asphalt mixture indicates a much higher temperature increase rate than the general asphalt mixture, and its surface temperature after 60 min is 7.5 ℃ higher. In addition, it reaches 0 ℃ from -10 ℃ at a rate 1.5 times higher than that required by the general asphalt mixture. When both 2% graphite and 1% carbon fiber are added, the thermal conductivity improves to 2.03 W/mK, and the conductivity is similar at all locations of the slab specimen location, which indicates no dispersibility issue. The results of the mechanical performance evaluation shows that the higher the ratio of the carbon material, the lower is the dynamic modulus and IDT at 20 ℃, which decreases the crack resistance. Meanwhile, the results of the Hamburg wheel-tracking test at 50 ℃ show an improvement in the permanent deformation resistance. CONCLUSIONS : The results of the conductivity and performance evaluation show that the optimal ratio is the combination of 2% graphite and 0.5% carbon fiber. This suggests that the conductive asphalt mixture incorporated with carbon materials can efficiently transfer heat generated from the heating layer at the bottom of the pavement to the pavement surface.

자기(瓷器)는 조선의 중요한 대외 교역 물품이 아니었다. 조선은 전국에 걸쳐 자리하는 가마에서 필요한 백자를 생산했으므로 자기를 만들지 못한 나라들과는 수입해서 사용하는 그 릇의 종류와 크기, 수량이 달랐다. 유럽 등지에서는 새롭고 이국적인 동아시아의 자기가 여 러 왕실과 귀족들의 수집품이 되었지만 조선은 자기 자체를 이미 수 세기 동안 일상의 그릇 으로 사용해왔으므로 다양한 문양이 장식된 일부 청화백자나 오채자기 위주로 중국과 일본의 자기를 들여왔다. 서울 시내 출토양상을 보자면 조선 후기 한양도성에 유입된 외국 자기의 수량은 조선 전 기에 비해 상대적으로 줄어드는 모양새다. 19세기 후반 이후에는 유상채 자기의 증가 현상 이 추가되지만 청화백자로 만든 발과 접시 등 반상기가 외국 자기의 주류를 이루는 특징은 조선 전기 이래로 계속 이어졌다. 조선시대 해외 교역이 사행이나 일부 상단을 중심으로 이루어지다 보니 중국과 일본의 물 산은 자연스럽게 왕실과 사행에 직접 참여하는 관리, 역관 혹은 상인 계층을 시작으로 소비 의 흐름이 마련되었다. 서울 시내에서 조선 후기 외국 자기들이 출토되는 유적이 궁궐이나 그 주변 혹은 시전행랑이 자리하는 종로대로 일대에 주로 위치하는 것도 이러한 상황이 반영 된 것으로 파악할 수 있다

Since its construction in the late 14th century, Hanyangdoseong had been carried out three major repairs and reconstructions during the 500 years of the Joseon Dynasty. In addition to the large-scale construction, small-scale construction continued until King Gojong era. In particular, in the 18th century, systematic construction management was implemented by the craftsmen and the military participated in the renovation of Hanyangdoseong in earnest, and the construction methods also developed rapidly. In the early 18th century, new construction techniques were attempted in various sections of the reconstruction work, and gradually became a common technology for repairing Hanyangdoseong in the late 18th century. The purpose of this study is to examine the characteristics and period of changes in the 18th century's construction technique, when the rapid development of Hanyangdoseong took place. To this end, the excavation results related to Hanyangdoseong, the remaining city wall, and the inscribed stones were used to identify and demonstrate the characteristics and change of the construction method.

The purpose of this study is to research about the construction of Chiseong around the Heunginjimun Gate area in the 18th century. the conclusions derived from the historical evidence of the number, location, size, and form, and construction method of Chiseong was as follows. First, the Chiseong(Square-shaped lookout) of Hanyangdoseong was built in the 29th year of King Yeongjo(1753) and can be found in the national record. Five sites of the Chiseong are currently identified. It is assumed that the Foru was installed on top of some of the Chiseongs. Second, Chiseong was destroyed sequentially in the first half of the 20th century. Third, Chiseong is a rectangular in shape and six are constructed. Fourth, Sixth Chiseong could figure out through Hengryeopungsokdo, the drawing of Jeong Seon.

This paper sought to examine characteristics and differences of the construction methods and the materials of the wall repair by three command through individual command records and national documents. This paper is based on the management section of three commands(Samgunyoung), which was in charge of a repair and management of Hanyangdoseong(Seoul city wall) in 18th century. The purpose and background of the study are as follows. First, through each inscribed stones on the rampart and the parapet, it is to grasp accurately the point of change of Hanyangdoseng after the 18th century. Second, through inscribed stones, the site evidence of the repair work in the late Joseon Dynasty, it is to find out the aspects of the development process of repair and reconstruction technology of Hanyangdoseng.

Much attention has been paid to thermally conductive materials for efficient heat dissipation of electronic devices to maintain their functionality and to support lifetime span. Hexagonal boron nitride (h-BN), which has a high thermal conductivity, is one of the most suitable materials for thermally conductive composites. In this study, we synthesize h-BN nanocrystals by pyrolysis of cost-effective precursors, boric acid, and melamine. Through pyrolysis at 900oC and subsequent annealing at 1500oC, h-BN nanoparticles with diameters of ~80 nm are synthesized. We demonstrate that the addition of small amounts of Eu-containing salts during the preparation of melamine borate precursors significantly enhanced the crystallinity of h-BN. In particular, addition of Eu assists the growth of h-BN nanoplatelets with diameters up to ~200 nm. Polymer composites containing both spherical Al2O3 (70 vol%) and Eu-doped h-BN nanoparticles (4 vol%) show an enhanced thermal conductivity (λ ~ 1.72W/mK), which is larger than the thermal conductivity of polymer composites containing spherical Al2O3 (70 vol%) as the sole fillers (λ ~ 1.48W/mK).

PURPOSES: The national highways and expressways in Korea constitute a total length of 17,951 km. Of this total length of pavement, the asphalt pavement has significantly deteriorated, having been in service for over 10 years. Currently, hot in-place recycling (HIR) is used as the rehabilitation method for the distressed asphalt pavement. The deteriorated pavement becomes over-heated, however, owing to uncontrolled heating capacity during the pre-heating process of HIR in the field. METHODS: In order to determine the appropriate heating method and capacity of the pre-heater at the HIR process, the heating temperature of asphalt pavement is numerically simulated with the finite element software ABAQUS. Furthermore, the heating transfer effects are simulated in order to determine the inner temperature as a function of the heating system (IR and wire). This temperature is ascertained at 300 ℃, 400℃, 500℃, 600℃, 700°℃, and 800℃ from a slab asphalt specimen prepared in the laboratory. The inner temperature of this specimen is measured at the surface and five different depths (1 cm, 2 cm, 3 cm, 4 cm, and 5 cm) by using a data logger. RESULTS: The numerical simulation results of the asphalt pavement heating temperature indicate that this temperature is extremely sensitive to increases in the heating temperature. Moreover, after 10 min of heating, the pavement temperature is 36%~38% and 8%~10% of the target temperature at depths of 25 mm and 50 mm, respectively, from the surface. Therefore, in order to achieve the target temperature at a depth of 50 mm in the slab asphalt specimen, greater heating is required of the IR system compared to that of the gas. CONCLUSIONS : Numerical simulation, via the finite element method, can be readily used to analyze the appropriate heating method and theoretical basis of the HIR method. The IR system would provide the best heating method and capacity of HIR heating processes in the field.

This paper is to clarify on the Characteristics of the Layout of the Hue, the Capital of the Nguyen Dynasty in Vietnam, based on a close study of historical records. The results of this study are as follows: Hue was organized according to the traditional capital system of China, whereas the city wall was built Western-style called Vauban. It can be said that the construction of Hue was the result of reflecting both the regional situation that was under the influence of the Chinese culture and the situation of the time that required military facilities based on new technologies. The Axis of Hue oriented to southeast and the location of the government facilities related to way of construction, using the existing facilities. Some facilities that must be located within the imperial city were built its outside. Because facilities for ancestor worship was more important. The facilities for ancestor worship was able to get confirmation that Nguyen Dynasty was successor of ruler who dominated the country.

한양도성은 한국의 전통 풍수 개념에 입각하여 주변 지형 과 지세를 이용하여 축조되었다. 또한 600년이 넘는 오랜 세월 동안 도시 안의 자연경관과 한국 전통 정신이 보존된 인류 문화유산이다. 본 연구는 한양도성 주변 지역에 대한 역사 문화적 가치를 재조명하고 한양도성의 가치를 높일 수 있도록 한양도성 주변의 보전대상 수목을 선정하고 이를 보호, 관리할 수 있는 방안을 제시하고자 수행하였다. 연구의 진행은 한양도성에 심겨진 전통 수종을 문헌을 통해 조사한 후, 현장조사 결과와 비교하였다. 보전대상 수 종 선정은 서울시 한양도성 수목보호관리지침에서 보존림, 상징수, 경관수로 구분한 것을 참고하여 문헌조사를 통한 수종 목록과 현장조사를 통한 수종 목록을 비교하였다. 보 전대상 수종의 보호관리방안은 한양도성 수목보호관리지 침을 참고하여 현장조사 결과를 중심으로 수목 보전을 위한 보전구역 설정과 수목 보전을 위한 관리 지침을 수립하였 다. 관리 대상 수목은 한양도성 수목보호관리지침에서 도성 에 피해를 주는 수목, 조망경관 개선을 위한 관리 수목, 도성 주변 외래수종 및 귀화식물, 환경부 지정 생태계 교란 식물 목록을 참고하여 선정하였다. 연구의 범위는 문헌은 한양도성이 축조되기 시작한 1395 년부터 최근 2015년까지의 연구와 전통 조경공간의 수종에 관한 연구를 검토하였고, 한양도성 주변 지역에 기록된 수 종을 살펴보았다. 현장조사는 2015년 4월 중에 이루어졌다. 현장조사 조사대상은 한양도성 전체 약 18km로 6개(백악, 인왕, 숭례문, 남산, 흥인지문, 낙산)의 지역으로 나누어 성 곽 잔존구역 5m 내외를 주요 식생조사의 범위로 삼았다. 연구 결과 문헌에서 조사한 한양도성 수목은 국립문화재 연구소의 보고서(2013)를 참고하여 총 78종을 목록화하였 다. 한양도성 주변에 관한 문헌에 기록된 수종은 7과 9속 11종으로 이중 소나무, 잣나무, 복사나무 등은 관상을 위해 심겨졌고, 뽕나무와 사과나무 등은 경제적인 목적으로 심겨 졌다고 구분하였다. 현장조사 결과 한양도성 주변 수종 식 물상은 50과 84속 91종 10변종 4품종으로 총 105분류군이 확인되었다. 분류된 수종은 나자식물(11.4%), 피자식물 (88.5%)로 이중 장미과 15종(14.2%), 소나무과 7종(6.6%), 콩과, 노박덩굴과, 물푸레나무과 5종(4.7%) 순으로 조사되 었다. 문헌조사와 현장조사 결과를 비교한 결과, 문헌에서 발굴된 종 중 현장에서 출현하지 않은 종은 총 31과 69속 77종으로 나타났다. 문헌 비교 결과 현장조사에서만 출현한 종은 44과 72속 81종으로 나타났다. 따라서 문헌조사 결과 와 현장조사 결과를 종합한 한양도성 보전대상 수종은 뽕나 무와 소나무를 포함한 총 19과 20속 25종으로 선정하였다. 구간별 보전대상 수종은 백악지역의 역사적인 상징물로 서 1․21사태 소나무를 상징수로 선정하였다. 또한 군사시설 내부의 소나무림은 한양도성의 상징수뿐만 아니라 경관수 로서도 가치가 있어 소나무 군락 전체를 보존림으로 지정하 여 관리할 필요가 있다. 인왕지역 중 사직터널 인접한 부근 에 심어진 뽕나무는 한양도성 밖에 거주하는 백성들의 생활 사를 엿볼 수 있으므로 상징수로서 가치가 있다. 숭례문 지 역은 도심 발달로 내사산과 접해 있는 다른 지역에 비해 성곽이 많이 소실되어 경관수나 상징수로 선정할 만한 수목 이 존재하지 않았다. 남산 지역은 내사산의 상징 수종인 소 나무와 참나무류의 비율이 높아 특히 남산 팔각정 근처 성 곽 주변의 느티나무가 경관수로 자리할 수 있다. 흥인지문 지역은 광희문 주변으로 소나무림이 경관수로 식재되어 있 다. 낙산 지역은 높은 구릉지를 따라 성곽이 이어져 성곽 안쪽 이화마을, 장수마을의 상징수로서 뽕나무가 있다. 보전 및 관리대상 수종의 관리 방안으로 첫째, 한양 도성 의 내부 5m, 외부 5m를 수목 보호구역으로 설정해야 한다. 둘째, 한양도성 주변 수목 보전 관리를 위하여 도성의 훼손 을 막기 위해 보전을 필요로 하는 수종은 목본류와 덩굴식물류로 나누어 관리해야 한다. 셋째, 한양도성 주변 관리대 상 수종의 관리방안은 한양도성이 전통 문화유산이므로 도 성과 인접한 5m이내 식재된 외래식물의 관리가 중요하다. 가이즈까향나무, 스트로브잣나무, 중국굴피나무, 칠엽수, ‘쇼조노무라’단풍나무, 일본잎갈나무 등 외래종은 이식이 필요하다.

This study aims to draw out planning principles and structure of Iksan imperial capital city in late Baekje, especially in view of the relationship among imperial capital city planning area, skeletal axis and the location of royal castle. With site survey and analysis of historical records, old maps, topographical maps, archeological excavation data, land registration map of 1915, some significant inferences were drawn out. Firstly from the point of topological conditions, the contiguous line of a stratum from Mireuk mountain(彌勒山) to Wangkung-ri castle(王宮里遺蹟) and two waterways made a topological axis of Iksan Imperial capital city. Secondly district of Iksan imperial capital city can be deduced to the inner area north to Kummado soil wall(金馬都 土城), south to the confluence of Iksan river(益山川) and Busang river(扶桑川), west to Okum mountain fortress(五 金山城) and Galjeon river(葛田川), east to line near to eastern wall of Jesuksa temple(帝釋寺). Iksan ssang-reung(益 山雙陵) was located outside western boundary line of capital city. Thirdly axis from Wangkung-ri castle to northern Kummado soil wall made a skeletal axis of city structure. It got through northern lowland along Buk river(北川) between Yonghwa(龍華山) and Mireuk mountain. Fourthly the location of royal palace can be deduced to the north part of the city around Kumma town area along the planning principle of northern royal palace.

The study will design the structural optimization of 30W LED heat sink using the thermal conductive plastic materials. The advantages of thermal conductive plastic heat sink are having formability and being able to lighten products. A heat sink was optimized in terms of the number, and the thickness of fins and the base thickness of the heat sink, using the Heatsinkdesigner software. Also by using SolidWorks Flow simulation and thermal analysis software, the thermal characteristics of the heat sink were analyzed. As the result, the optimized heat sink has 22 fins, which are 1.5mm thick and a 3.8mm-thick base. The weight of the heat sink was 310g, and the highest and the lowest temperature were 64.93℃ and 45.96℃ respectively. Because of the low thermal conductivity of the thermal conductive plastic, the highest and the lowest temperature of the thermal conductive plastic heat sink were 14.3℃ higher and 2.19℃ lower respectively than an aluminum heat sink

This study analyzed the thermal properties of a thermal conductive polymer polyethylene terephthalate(PET) to make it into a heat sink and evaluated the temperature properties of 10W COB(chip on board) LED(Ligth Emitting Diode) as a heat sink. This study confirmed the composition and content of inorganic compounds in PET. As a result, carbon filler content of Samples A and B accounted for 73.93 and 61.46%, respectively. Sample B included 10% more inorganic filler(Al, Mg, Si, Ca), and its thermal conductivity was 10.9 W/mk higher than Sample A. Based on the material properties, this study compared the heat dissipation properties of 10W COB LED between PET and aluminum heat sinks. As a result, the maximum temperature of PET heat sink was 4.4℃ higher than that of aluminum heat sink, and the minimum temperature outside PET heat sink was 13.6℃ lower than that of aluminum heat sink. Based on these results, PET heat sinks are inferior to aluminum heat sinks in thermal properties. However, it is considered possible to realize various designs because they have excellent formability and lightweight properties due to the lower melting point and specific gravity