• Ecology and Resilient Infrastructure
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• 제2권2호
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• pp.128-136
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• 2015

하천공간이란 하천시스템과 관련된 물리적 생태적 프로세스에 영향을 받는 홍수터, 하도를 모두 포함하는 공간을 의미하므로, 제방에 의해 인위적으로 차단된 현재의 하천구역과는 분명히 구분된다. 본 연구에서는 하천기능 평가를 위한 공간경계를 결정하기 위하여 홍수터 공간을 획정하는 방안을 제시하고자 한다. 이를 위하여, 지형분석 방법과 범람분석 방법을 이용하였고, 각 방법으로 산정된 만경강 홍수터 공간을 비교, 검토하였다. 분석결과, 지형분석은 곡저의 추출에 적합하며 현재의 수문지형조건을 반영하는 범람공간과는 차이가 있음을 확인하였다. 또한 빈도별 범람면적을 비교함으로써, 하천 상류 혹은 하류 구간의 구분없이, 100년 빈도 범람지역을 하천공간으로 획정하는 것이 타당할 것으로 판단되었다. 그러나, 하도의 분기가 발생되는 일부 구간에서는 지형학적 곡저 분석 결과와 다양한 빈도의 범람해석 결과와의 비교가 필요하다.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2006년도 International Symposium on GPS/GNSS Vol.2
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• pp.297-301
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• 2006

There are more than thirty continuously recording GPS stations (CORS) have been set up at different geological sites and distributed throughout a 140 km by 140 km area in southern Taiwan beginning since 2000, and the amount of the CORS are still under increasing in this area which is recognized the suture zone between the Philippe sea plate and Eurasia plate. From the year 2000 to the end of 2005, we analyze the daily solutions to obtain the average station velocities before and after the Chengkung earthquake which occurred near eastern Taiwan at 04:38 UTC on 10 December 2003. After considering the effects of the coseismic and postseismic displacements, the difference of the horizontal components reaches 13 mm/year of the average station velocity happened in the east side of the Central Range. To the vertical component, all of the stations are risen which located in the Coastal Range, and the largest difference approaches 20mm/year.

• 한국물환경학회지
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• 제34권5호
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• pp.447-461
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• 2018

To realize river restoration that ecological characteristics of the river are reflected, we classified the river into four reaches of valley stream, upstream, midstream, and downstream based on substrate as well as riverbed gradient obtained from the relationship between distance from the river mouth, and above sea level. Considering that the rivers of Korea have been dominated by various and intense artificial interferences over a lengthy period, we determined cross sectional range of the river based on the geological map and clarified transformation degree by reach. Vegetation profile diagram was prepared by depicting horizontal range and vertical stratification of major vegetation appearing in a belt transect of 10 m breadth installed between weirs constructed in both sides of the river. Restoration models by river reach were prepared based on breadth of waterway, bare ground, herb, shrub, and tree dominated vegetation zones on vegetation profiles wherein a flooding regime was reflected. Species composition information collected from vegetation established in each zone was systematized to use for restoring each reach ecologically. Further, background that longitudinal reaches and horizontal zones were divided, was discussed by comparing with case studies in foreign countries. In addition, necessity of ecological restoration of the river was discussed based on degree of integrity of Korean rivers, ecological significance of riparian vegetation, and importance of reference information for ecological restoration of the river.

• 대한치과보철학회지
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• 제47권4호
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• pp.424-434
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• 2009

연구목적: 임플란트는 수직교합 하중에는 비교적 잘 견디나 측방하중에 대해서는 약한 역학적 성질을 갖고 있으므로 임플란트의 재료 특성과 기하학적 형태에 따른 응력 분석 연구의 필요성이 제기되고 있다. 연구재료 및 방법: 외부육각구조를 갖는 28개의 임플란트를 7개씩 4군으로 나누어 그 제품에 적합한 UCLA gold abutment를 이용해, 제3형 금합금으로 보철 물을 제작하였고, A군 (3i, FULL $OSSEOTITE^{(R)}$-Implant), B군 (Nobelbiocare, Branemark $System^{(R)}$Mk III Groovy RP), C군 (Neobiotec, $SinusQuick^{(TM)}$ EB), D군 (Osstem, US-II)으로 분류하였다. 고정체와 지대주나사, 지대주를 연결한 후 수직적으로 절단하여 연마한 후 미세경도계를 이용하여 10군데에서 경도측정을 실시하였고, 동적하중 피로시험기를 이용하여 60-600 N범위로 파절시까지 동적 하중을 가하였다. 주사전자현미경을 이용하여 지대주나사 및 고정체의 파절 양상과 파절 위치 등을 관찰하였고, 유한요소분석을 통해 고정체와 지대주 나사에 나타나는 응력 분포와 파절면을 비교 분석하였다. 결과: 1.고정체 경도는 A, B, C, D군에서 각각 245.3, 289.7, 281.3, 300.4 Hv로 D군이 가장 높았고, A군이 가장 낮았다. 지대주 나사의 경도는 A, B, C, D군에서 각각 340.00, 317.62, 306.5, 306.2 Hv로 A군이 가장 높고, D군이 가장 낮았다. 2. 모든 실험군에서 임플란트 고정체의 파절은 응력이 집중되는 고정체 3-4번째 나사산 홈 (valley) 부위 또는 내면의 사공간부와 일치하는 부위에서 발생되었고, 피로수명은 A, B, C, D군에서 각각 31585, 47311, 30141, 105371로 D군이 가장 높았으며, A, B, C군과는 유의한 차이가 있었다(P<.05). 3. 파절양상은 B군과D군에서는 고정체와 나사 모두에서 수직 (longitudinal)파절과 수평 (transverse)파절이 동시에 일어나는 복합 (complex mode) 파절이 관찰 되었고, A와 C군에서는 고정체에서 수평 (transverse mode) 파절만이 관찰되었다. 4. 유한요소분석 결과 인장응력이 가장 높은 고정체 표면부에서 피로 균열이 시발되어 압축응력이 가장 높은 반대편 부위로 피로균열이 전파되었으며, 최대 유효 응력값은 C군이 가장 높았고, B군에서 가장 낮았다. 결론: 피질골 높이와 일치하는 임플란트 고정체 부위에서 최대 인장 주응력이 발생되며, 고정체 사공간부 (dead space)가 최대 인장 주응력이 작용하는 지그 표면과 일치할 때 피로파절이 발생되었다. 따라서 악골에 식립된 임플란트의 신뢰성을 향상시키고 수명을 증대시키기 위해서는 가능한 임플란트 주위의 골소실이 일어나지 않도록 해야 할 것이나 골흡수가 일어나 사공간부 수준까지 진행된다면 임플란트의 파절 빈도가 증가될 수 있으므로 이에 대한 대처가 필요할 것으로 사료된다.

• 건축역사연구
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• 제3권1호
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• pp.83-99
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• 1994

Ch'ang-Ts'al-Ts'un is a rural Village near Lung-jing City in Yen-pien Korean Autonomous Province of China. It was formed about 100 years ago by Korean Immigrants and has been developed maintaing the characteristics of traditional Korean architecture. Therefore investigating the spatial structure of this village is a meanigful work to confirm and explore one branch of Korean architecture. This study aims at analyzing the spatial structure of the village using direct data collected from the field work and indirect data from books and maps. The field work consists of on-the-site survey of the village layout, interviews of residents, observation notes and photography. Ch'ang-Ts'ai-Ts'un is located 360-370 m high above the sea level and at the side of a long valley. A river flows in the middle of the valley and relatively flat arable land exists at the both sides of the river. The location of the village related to the surrounding river and mountains suggests that the site of the village was chosen according to Feng-Shui, Chinese and Korean traditional architectural theory. The main direction of the house layouts is South-western. The village has been growing gradually until today. Therefore it is meaningful to make the village layout before Liberation(1946 A.D.) because the characteristics of Korean architecture prevailed more in that period. The area of the previous village is limited to the west side of the creek. New houses were later added to the east of the creek, forming a 'New Village'. Previously the village was composed of 3 small villages: Up, Middle and Down. Also the main access roads connecting the village with the neighboring villages were penetrating the village transversely. Presently the main access road comes to the village longitudinally from the main highway located in front of the village. The retrospective layout shows the existence of well-formed Territory, Places and Axes, thus suggesting a coherent Micro-cosmos. The boundary of imaginery territory perceived by present residents could be defined by linking conspicous outside places sorrounding the village such as Five-mountains, Front-mountain, Shin-dong village, Standing-rock, Rear-mountain and Myong-dong village. Inside the territory there are also the important places such as Bus-stop, Memorial tower of patriots, Road-maitenance building and the village itself. And inside it 5 transverse and 1 longitudinal axes exist in the form of river, roads and mountains. The perceived spatial structure of the village formed by Places, Axes and Territory is geometrical and well-balanced and suggests this village is fit for human settlement. The administrative area of the village is about 738 ha, 27 % of which is cultivated land and the rest is mountain area. Initially the village and surrounndings were covered with natural forest But the trees have been gradually cut down for building and warning houses, resulting in the present barren and artificial landscape with bare mountains and cultivated land. At present the area of the village occupied by houses is wedge-shaped, 600 m wide and 220 m deep in its maximum. The total area of the village is $122,175m^{2}$. The area and the rate of each sub-division arc as follow. 116 house-lots $91,465m^{2}$ (74.9 %) Land for public buildings and shops $2,980m^{2}$ (2.4 %) Roads $17,106m^{2}$ (14.0 %) Creek $1,356m^{2}$ (1.1 %) Vacant spaces and others $9,268m^{2}$ (7.6 %) TOTAL $122,175m^{2}$ (100.0 %) Each lot is fenced around with vertical wooden pannels 1.5-1.8 m high and each house is located to the backside of the lot. The open space of a lot is sub-divided into three areas using the same wooden fence: Front yard, Back yard and Access area. Front and back yards are generally used for crop-cultivation, the custom of which is rare in Korea. The number of lots is 116 and the average size of area is $694.7m^{2}$. Outdoor spaces in the village such as roads, vacant spaces, front yard of the cultural hall, front yard of shops and spacse around the creek are good 'behavioral settings' frequently used by residents for play, chatting, drinking and movie-watching. The road system of the village is net-shaped, having T-junctions in intersections. The road could be graded to 4 categories according to their functions: Access roads, Inner trunk roads, Connecting roads and Culs-de-sac. The total length of the road inside the village is 3,709 m and the average width is 4.6 m. The main direction of the road in the village is NNE-SSE and ESE-WNW, crossing with right angles. Conclusively, the spatial structure of Ch'ang-Ts'ai-Ts'un village consists of various components in different dimensions and these components form a coherent structure in each dimension. Therefore the village has a proper spatial structure meaningful and appropriate for human living.

• 한국산림과학회지
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• 제110권4호
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• pp.622-629
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• 2021

본 연구는 목재생산시대를 대비하여 점차 대형화되어 가는 목재운송차량의 원활한 통행을 위해 춘천·홍천 국유림 관리소 관내 간선임도 4개 노선 11.3 km를 대상으로 임도의 구조상태에 따른 대형 목재운송차량(25톤 규모)의 주행속도를 분석하였다. 임도의 평면선형에 따른 주행속도는 곡선구간이 평균 7.6 km/h로 평균 8.7 km/h인 직선구간보다 낮은 것으로 나타났으며, 전체적으로 간선임도 최저 설계속도인 20 km/h에 비해 직선구간의 경우 약 44%, 곡선구간의 경우 약 38% 수준인 것으로 나타나 최소한의 주행속도 확보를 위해 임도 구조개선이 필요한 것으로 나타났다. 종단기울기에 따른 주행속도는 최대 13%까지 주행속도에 큰 차이가 없는 것으로 나타났으며, 직선구간 거리별로는 100 m 이상에서 주행속도가 증가하는 것으로 나타났다. 곡선구간의 시설위치별로는 능선부가 계곡부보다 6.2~9.3% 낮은 주행속도를 나타냈다. 진출입 각도 및 곡선반지름별 주행속도는 진출입 각도가 90° 미만, 곡선반지름 15m 미만일 때 가장 낮은 것으로 나타났으며, 곡선반지름 15m 미만일 때 확폭량 기준에 미달되는 구간이 50% 이상으로 충분한 확폭이 이루어지지 못한 것으로 나타났다.