• Proceedings of the Korean Vacuum Society Conference
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• 2011.08a
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• pp.203-203
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• 2011

The importance of stepped single-crystal surfaces as model catalysts has been well recognized [1]. We re-investigated the adsorption properties of $H_2$ and CO, most important species in platinum-based catalysts, on nearly defect-free and highly stepped surfaces of one and the same Pt(111) crystal. While both being symmetric and single-peaked from the nearly defect-free surface, temperature-programmed desorption (TPD) spectra from the highly stepped surface saturated at 90 K with H and CO were triply- and doubly-peaked, respectively. Once pre-adsorbed, CO preempted step and then terrace sites, inhibiting the dissociative $H_2$ adsorption completely. Pre-adsorbed H inhibited the CO adsorption on terrace sites only, leaving defect sites intact for CO adsorption even at the saturation H precoverage. On defect-free Pt(111), while pre-adsorbed CO inhibited the dissociative $H_2$ adsorption completely, pre-adsorbed H could not inhibit the CO adsorption completely. These intriguing, but interesting results are discussed in terms of energetics/kinetics and the role of surface step sites in the dissociative adsorption of $H_2$ on Pt(111) [2].

• Proceedings of the Korean Vacuum Society Conference
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• 2012.02a
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• pp.132-132
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• 2012

Depositing $CaF_2$[0.6% lattice-mismatch] on the Si(001)-$4^{\circ}$ off surface [composed of a single (001) domain with regularly-arrayed double-layer DB steps and located between (1 1 19) and (1 1 21)] held at $700^{\circ}C$, $CaF_2$ molecules are preferentially adsorbed on the dimers and dissociated to Ca and F atoms. Dissociated Ca atoms form a silicide layer of a $2{\times}3$ structure on the (001) terrace, while F atoms are desorbed from the surface. Once the terrace is covered with a calcium silicide layer, CaF starts to be adsorbed selectively on the steps, as shown in Fig. (a). With $CaF_2$ deposition exceeding 1 ML, the (1 1 17) surface having 1-D $CaF_2$ nanodots are formed as shown in Fig. (b). By the present STM study, it has been clearly disclosed that the calcium silicide interfacial layer is preformed prior to adsorption of $CaF_2$ on vicinal Si(001) surface.

• Journal of Biosystems Engineering
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• v.4 no.1
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• pp.24-34
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• 1979

현재 실용테라스 (Terrace) 축조비용의 추정은 단위 테라스장이나 이동토양의 단가에 근거하고 있다. 그런, 근래 l국의 옥수수 지대 (corn belt)에서 널리 이용되고 있는 평행형 테라스의 경우 각 지점마다 성토 및 절토양이 다르기 때문에 이들 방법은 적합하지 않다. 이들 테라스의 경우 테라스장을 따라 토양의 이동이 불가피하므로 차륜형 자적식 스크레이퍼(scraper)가 테라스 축조에 널리 사용되고 있다. 본연구의 목적은 테라스 축조기계의 운행거리에 근거하여 테라스 축조시의 토공비용을 추정하기 위한 새로운 방법을 개발하는데 있었다. 테라스 축조시 토공작업은 전적으로 스크레이퍼에 의해서 , 그리고 테라스 경호장의 마무리 작업은 모트그레이터 (motor grader )에 의하여 수행되는 것을 가정하였다. 이들 기계의 세부적인 수행동작은 테라스 각지점에서의 절토와 성토량 및 이들 토양의 처리를 디지털 컴퓨터(digital computer)를 이용하므로서 계산할 수 있었다. 또한 테라스 축조에 소요되는 토양은 전적으로 테라스 수로부문에서 절취하는 것으로 가정하였다. (즉, 테라스 전장의 총절토양 과 총성토양은 같음) 연구결과 다음과 같은 결론을 얻었다. 1. 성토 및 절토양이 균형된 테라스에 있어서는 스크레이퍼의 운행거리에 근거하여 토공비용을 추정할 수 있는 방법의 개발이 가능하다. 2. 스크레이퍼의 수행구간, 회수 및 토공비용을 결정하기 위해서는 컴퓨터 방법을 이용하는 것이 필요하다. 3. 새로운 컴퓨터 모델은 예시의 테라스에 적용한 결과 테라스 토공비용을 추정하는 데 적합함을 보여주었다. 4. 이 방법은 테라스 축조에 있어서 효율적인 스크레이퍼의 적용에 지침이 될 수 있다.

• Proceeding of Spring/Autumn Annual Conference of KHA
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• 2008.04a
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• pp.151-155
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• 2008

Modernization of cities and housing in Malaysia is the history of the establishment of international trading ports due to worldwide maritime trade and exchange. In cosmopolitan cities, new housing typology appeared from the influence of various ethnic immigrants and with the fusion of traditional Malaysian housing characteristics. This study is focus on classifying the representative housing typology of Malaysia produced through the Modernizaiton of cities. Through reference review and field study, Malaysian Modern housing can be classified into 2 categories. The first one is the transformation of traditional housing. Representative typology is shophouse. Shophouses were imported from the South Coast of China and transformed into Malaysian urban housing. And the other typology is bugalow. Bugalow is the result of the fusion of traditional timber house and Western palazzo. Secondly is urban housing typology. Modern urbanization required maximum utilization of land and new typologies in the form of multi-story apartments, flats and terrace house were developed to accomodate new needs. In the sub-urban areas, the English terrace houses typology was adopted which is based on the British system of land sub-division. And nowdays luxurious housing typology, condominium is one of the popular housing for medium and high society.

• The Korean Journal of Quaternary Research
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• v.18 no.1 s.22
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• pp.41-46
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• 2004

The fluvia(thalassostatic) terraces have been developed among the lower Yeongsan river, near the southwestern coastal region of Korean peninsula. These thalassostatic terraces could be classified into 3 surface, i. e., Yeongsan 32m, 18m, and 10m surface, in desending order, according to the relative heights from the river floor. Yeongsan 32m, 18m and 10m surfaces were corresponded to the mMT3, mLT1 and mLT2 surfaces of Choi(2003), respectively. It was revealed that the mLT1 surface was the marine terraces which had been formed in the Last Interglacial culmination period(oxygen isotope stage 5e) in the southeastern coast of Korean peninsula.

• Journal of Ecology and Environment
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• v.42 no.4
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• pp.150-154
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• 2018

In lotic wetlands, runner reed (Phragmites japonicus) plays a role as a pioneer, which helps other plant species to settle by making dense roots trapping floating-sediments. In lentic wetlands, on the other hand, P. japonicus could play a role as an invader threatening biodiversity by forming tall and dense stands. To conserve an abandoned paddy terrace in mountainous areas, a habitat of an endangered dragonfly species (Nannophya pygmaea), from the monotypic-occupation by P. japonicus, we applied three kinds of treatment: (1) hand-clipping in 2009, (2) mechanical excavating in 2012, and (3) planting of alternative vegetational unit in 2012. We have monitored vegetation changes in the wetland in 2008~2012 and 2017. Vegetation cover of P. japonicus sharply decreased from 43% in 2011 to 16% in 2012 by the mechanical excavation. After 5 years from applying the treatment, Schoenoplectiella mucronata that was utilized in the planting became the predominant species instead of P. japonicus and the number of wetland plant species increased from 16 to 25 with the shift in species composition. This study showed the utility of three control methods of P. japonicas in a lentic wetland.

• Journal of architectural history
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• v.28 no.1
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• pp.7-16
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• 2019

As a part of the research on existing structures of private homes from Joseon Era. Focusing on one hundred twenty five-purlin houses, the current study investigated the features and characteristics of the house structure from style, size, proportion and roof pitch, and measurements of key parts, and developed the following conclusions. Most are single-houses (89, 83%), and among them, there are 47 single front-terrace houses (39%), which is the highest number. The sizes of lower house structure do not differ greatly depending on the vertical structure, and single rear terrace house and double-house have relatively larger side sizes. The size of upper structure is larger in double-houses compared to other vertical structures, indicating a relatively higher roof. The cross-section measurement of major parts show that double-houses are larger than single-houses by 3cm in pillar, 3-4.5cm in crossbeam length, and 4.5cm in crossbeam width. However, Janghyeo width was consistent at 7.5 to 10.5cm, maintaining uniformity regardless of vertical structure of the houses. In addition, the cross-section measurements decreased from sixteenth to nineteenth century, with the size of pillar size decreasing the most. The result that the Janghyeo width is not related to the house structure house confirmed that the Janghyeo width was kept consistent regardless of the size of the house structure.

• Journal of The Geomorphological Association of Korea
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• v.25 no.2
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• pp.31-42
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• 2018

This study analyzes the spatial distribution of the highest level terrace which can be regarded as an initial land surface before the uplift of the Taebaek Mountains and estimates spatial characteristics of the incision and uplift rates around the Mountains. The altitude above the riverbed of the 54 highest level terraces seems to be greatly influenced by the incision of large stream and their elevation shows a high correlation with the uplift of the Mountains. The elevation of the terraces in the north and middle parts decreases westward with a rate of 5~6 m/km and meets with the sea level at area 100~120 km apart from the Mountains. Therefore, it can be suggested that the west coast of Korea might have generally experienced subsidence during the Quaternary. The elevation of the terraces suggests that area with a direction of N-S or NNW-SSE from Yeoryang-myeon, Jeongseon-gun to Taebaek-si shows the highest uplift rate around the Mountains and area with a direction of N-S connecting Girin-myeon, Inje-gun and Pyeongchang-eup, Pyeongchang-gun also indicates a high uplift rate.

• Journal of The Geomorphological Association of Korea
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• v.27 no.1
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• pp.47-60
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• 2020

This study tried to produce an uplift rate map and reveal the spatial distribution of the rate with topographical characteristics and absolute ages on marine terrace in the East Coast of the Korean Peninsula. Based on a total of 57 ages at 26 sites from previous study and 13 ages at 13 sites from this study, the coast showed the rates ranging from 0.145 m/ka to 0.410m/ka with an average of 0.258 m/ka. The highest and lowest rates were found from the Jeongdongjin area in Gangneung and the Goraebul area in Yeongdeok, respectively. However, some areas in the coast showed large differences in the rate among the sites. In addition, areas with only 1 age were also found, indicative of low reliability. This study suggests that a more reliable and precise interpretation on the rate can be made with more ages identified, especially in Goseong to northern part of Gangneung, middle and southern parts of Samcheok and Yeongdeok, southern part of Pohang to northern part of Gyeongju, and Ulsan.

• Journal of The Geomorphological Association of Korea
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• v.27 no.4
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• pp.29-39
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• 2020

This study estimated influences of the Ulsan Fault on tectonic movement and uplift characteristics in the Eastern Block of the Ulsan Fault. The averaged uplift rate in the Northern Coast of the Eastern Block was 0.202 m/ka, while the site in Seokbyeong-ri, Guryongpo-eup, Pohang-si, showed relatively high rate of 0.249 m/ka, attributable to influences of small fault movement, called the Gangsa Fault. Higher averaged rate of 0.270 m/ka than in the Northern Coast was calculated in the Southern Coast of the Eastern Block. The site in north of Haseo-ri, Yangnam-myeon, Gyeongju-si, showed the highest rate, suggesting influences of the Eupcheon Fault. The Western Block of the Ulsan Fault indicated the averaged rate of 0.208 m/ka, similar to that of the Northern Coast. The sites approximately 10 km apart from the Ulsan Fault showed 1.3 times higher rate in the Eastern Block than in the Western Block, while similar rates were calculated in the sites >20 km apart from the Ulsan Fault. These distributions of the rate suggest that the Ulsan Fault has significantly influenced development of marine terrace and tectonic movement in the study area, while local fault movements have also played a role.