• Journal of the Korean Geosynthetics Society
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• v.5 no.4
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• pp.11-18
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• 2006

Geotextile has been used for various types of containers, such as small hand-filled sandbags, 3-dimensional fabric forms for concrete paste, large soil and aggregate filled geotextile gabion, prefabricated hydraulically filled containers. They are hydraulically filled with dredged materials and have been applied in coastal protection and scour protection, dewatering method of slurry, temporary working platform for bridge construction, temporary embankment for spill way dam construction. Recently, geotextile tube technology is no longer alternative construction technique but suitable desired solution. The paper presents the stability behavior of geotextile tube composite structure by 2-D limit equilibrium and slope stability analysis. 2-D limit equilibrium analysis was performed to evaluate the stability of geotextile tube composite structure to the lateral earth pressure and also transient seepage and stability analysis were conducted to determine the pore pressure distribution by tide variation and slope stability. Based on the results of this paper, the three types of geotextile tube composite structure is stable and also slope stability of overall geotextile tube composite structures is stable with the variation of tidal conditions.

• Journal of Genetic Medicine
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• v.7 no.2
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• pp.145-150
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• 2010

Acrodysostosis is an extremely rare disorder characterized by short fingers and toes with peripheral dysostosis, nasal hypoplasia, and mental retardation. We report a 16-year-old Korean boy with acrodysostosis who had characteristic clinical features and cervical spine stenosis manifested by neurologic symptoms. On presentation, he complained of difficulty in raising his arms, and suffered from intermittent pain and weakness in both upper extremities. He had short stature and dysmorphic facial features, including a broad, depressed nasal bridge, small, upturned nose, bilateral epicanthal folds, and mild hypertelorism. Moderate mental retardation and sensorineural hearing loss in both ears were also present. Radiological findings included broad, short metacarpals and phalanges with cone-shaped epiphyses, bilateral Madelung deformities, hypertrophied first metatarsals, and thickening of the calvarium. Magnetic resonance imaging findings included stenosis of the cervical spine, platybasia with compression into the cervicomedullary junction, and downward displacement of the cerebellar tonsils. Here, we report a case of acrodysostosis with symptoms and signs of cervical spinal stenosis first in Korea. If it is diagnosed in the early stages, possible life-threatening complications, including spinal canal stenosis, can be managed properly and permanent neurologic sequelae might be avoided. Therefore, it is important to consider acrodysostosis in the differential diagnosis of peripheral dysostosis.

• Proceedings of the Korea Water Resources Association Conference
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• 2016.05a
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• pp.447-447
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• 2016

홍수 시 하천을 따라 유하되는 유송잡물(잡목, 생활쓰레기 등)은 구조물에 집적이 이루어지며 이로 인해 물의 흐름을 방해하고 구조물 주변의 지반을 약화시키거나 월류로 인해 심각한 피해를 야기 시킨다. 교량의 경우 유송잡물의 집적은 교각의 항력을 증가시켜 전도파괴를 유발시킬 수 있으며, 교각주변 흐름교란을 통한 하상세굴로 인해 기초부를 파괴시키기도 한다. 또한 통수단면적 증가로 인해 높아진 수위는 제방을 월류시켜 재산 및 인명피해를 유발하기도 한다. 암거의 경우 유송잡물을 포함한 토사로 인해 단면폐색 및 침식으로 암거의 파괴를 발생시키고 이로인해 도로의 단절을 가져오기도 한다. 이러한 유송잡물에 대한 차단대책은 현재 까지 유지관리를 통한 방법만이 최선책으로 제시되고 있다. 본 연구는 국외에서 소개되고 있는 유송잡물 피해저감시설을 대상으로 축소모형실험을 통해 효과를 확인하고 이를 통해 저감시설의 효율에 대해 소개하고자 하는 것이 주목적이다. 유송잡물 저감시설은 교량의 경우 수직분리대 방법, 우회말뚝 방법, 스위퍼를 이용한 방법으로 소개하고 있으며 이들 방법의 특징은 유송잡물 우회를 통해 집적을 저감하는 방식이다. 암거의 경우 수직분리대 방법, 스크린 방법, 우회스크린을 이용하는 방법 등이 있으며 수직분리대는 교량과 마찬가지로 우회방식을 기본방식으로 스크린 방식은 유송잡물의 차단을 원칙으로 하고 있다. 실험의 결과는 교량과 암거의 차단시설 유무에 따른 유송잡물의 집적률을 대상으로 하였다. 차단시설이 없는 경우 교량에서의 집적률은 97.9% ~ 99.2%의 집적률로 나타났다. 수직분리대의 경우 유송잡물 집적률은 49.3%, 우회말뚝은 0.0% ~ 4.2%의 범위로 매우 높은 차단효과를 보이고 있었다. 스위퍼방식의 경우 집적률은 5.3% ~ 20.9%로 나타났다. 이러한 결과로 판단하였을 때 차단시설 설치로 인한 교량에 대한 직접적인 차단효과는 수직분리대 < 스위퍼 < 우회말뚝 순으로 높은 차단효과를 보이는 것으로 나타났다. 그러나 우회말뚝에서의 집적률이 한계치를 넘어선다면 유송잡물로 인해 흐름교란, 수위 및 하상변동, 말뚝의 유실 등으로 인한 피해가 예상된다. 암거대상 유송잡물 차단시설 실험결과는 수직분리대의 경우 type과 투하방법에 따라 차이가 있지만 집적률은 14.7% ~ 64.9%의 범위로 나타났다. 스크린과 우회스크린 방식은 유송잡물의 우회가 아닌 차단이 목적이므로 유송잡물 집적에 의한 수위상승이 우려되는바 수위영향을 검토하였다. 검토결과 스크린 설치로 인한 수위상승이 우회스크린보다 높게 상승하는 것으로 나타났다. 이러한 결과는 스크린의 형태적인 측면에서 2면을 통해 집적되는 특성을 갖는 우회스크린이 통수단면적을 많이 확보하기 때문이다. 따라서 국부적인 수위상승으로 인한 피해를 저감하기 위해서는 설치여건이 허용된다면 통수단면적 확보가 유리한 우회스크린 설치가 유리할 것으로 판단된다.

• Journal of Korea Water Resources Association
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• v.54 no.12
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• pp.1285-1294
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• 2021

In recent years, as rainfall is concentrated and rainfall intensity increases worldwide due to climate change, the scale of flood damage is increasing. Rainfall of a previously unobserved magnitude falls, and the rainy season lasts for a long time on record. In particular, these damages are concentrated in ASEAN countries, and at least 20 million people among ASEAN countries are affected by frequent flooding due to recent sea level rise, typhoons and torrential rain. Korea supports the domestic flood warning system to ASEAN countries through various ODA projects, but the communication network is unstable, so there is a limit to the central control method alone. Therefore, in this study, an artificial intelligence-based flood prediction model was developed to develop an observation station that can observe water level and rainfall, and even predict and warn floods at once at one observation station. Training, validation and testing were carried out for 0.5, 1, 2, 3, and 6 hours of lead time using the rainfall and water level observation data in 10-minute units from 2009 to 2020 at Junjukbi-bridge station of Seolma stream. LSTM was applied to artificial intelligence algorithm. As a result of the study, it showed excellent results in model fit and error for all lead time. In the case of a short arrival time due to a small watershed and a large watershed slope such as Seolma stream, a lead time of 1 hour will show very good prediction results. In addition, it is expected that a longer lead time is possible depending on the size and slope of the watershed.

• Journal of the Korean Geotechnical Society
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• v.37 no.11
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• pp.51-60
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• 2021

River scour erodes the soil around the pier, reducing the lateral bearing capacity of the pier and lowering the stability of the structure. In this study, in order to examine the effect of scouring on the stability of the structure, an experiment was performed to measure the natural frequency of the pier according to the excavation of the surrounding ground. Impact vibration test was conducted on the pier with the caisson foundation of the Mangyeonggang Bridge, which is scheduled to be demolished. Accelerometers were attached to the top, center, and bottom of the pier and the acceleration responses were measured by hitting those three points. The experimental results showed that the top hit showed consistent and reasonable results of the acceleration responses according to the hitting position. The measured accelerations were converted to the frequency domain through Fast Fourier Transform (FFT), and then the natural frequency was determined. In addition, to analyze the scour effect on the natural frequency of the pier, the ground around the pier was excavated and the natural frequency change was analyzed. As a result, the natural frequency showed the decreasing tendency according to the excavation depth, but the decrease was small due to the large stiffness of the caisson foundation.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2003.05a
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• pp.181-186
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• 2003

The satellite navigation system is widely used for identifying a user's position regardless of weather or geographic conditions and also make effect on new technology of marine LBS(Location Based Service), which has the technology of geographic information such as the ENC. Generally, there are conceivable systems of marine LBS such as ECDIS, or ECS that use the ENC itself with powerful processor in installed type on ships bridge. Since the ENC is relatively heavy structure with dummy format for data transfer between different systems, we should reduce the ENC to small and compact size in order to use it in mobile platform. In this paper, we assumed that the mobile system like PDA, or Webpad can be used for small capability of mobile platform. However, the ENC should be updated periodically by update profile data produced by HO. If we would reduce the ENC without a consideration of update, we could not get newly updated data furthermore. As summary, we studied considerations for ENC reduction with update capability. It will make the ENC be useful in many mobile platforms for various applications.

• Journal of Venture Innovation
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• v.2 no.2
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• pp.31-46
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• 2019

Materials and Parts acts as the bridge in the manufacturing industry. In 2018, the materials and parts industry became the leading industry in Korea as its export reached $316.2 billion, accounting for 52.3 percent of the country's total exports. As such, it is the main industry of Korea leading the trade surplus, but when it comes to Japan, it is not. The trade deficit with Japan shrinks to $24 billion last year but the materials and parts industry still accounts for 60 percent of total deficit, which is about $15.1 billion. Today Japan has the top competitiveness in the high-tech materials and parts industry and the factors can be found in cooperation and symbiosis among companies, monotsukuri spirit, and long-term government policy. In order for Korean economy to pursue the Japan's high-tech materials and parts industry, the following change of perception is necessary. First, the material and parts industry requires win-win cooperation. In general, materials and parts are intermediate products. Therefore, it is important to understand the characterist that the transactions are all made up between companies not the with consumers. Second, expansion of joint technology development is absolutely necessary. South Korea is a leading country in the field of general-purpose materials and parts. However, the research shows that South Korea has structure which small and medium-sized companies could have difficulties in developing high-tech products as finding demand and developing market are hard due to low participation of large corporations at R&D stage. It is necessary for large corporations to participate in joint R&D and share opinions of customers from the beginning stage of R&D. Third, a long-term approach is needed. Structural vulnerabilities in the Korea's materials and parts industry, including the lack of advanced technologies is the main reason of solidification of Korea's trade deficit with Japan but there are also cultural differences about technology in the background. Even if it takes time, a long-term approach is absolutely necessary to build up technology and know-how in order to secure competitiveness in the high-tech materials and parts industry. This approach applies to act of corporation and government policy.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.32 no.2
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• pp.82-94
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• 2014

This study aims to comprehend that Gwanghalluwon for aspects of landscape change in terms of construction garden(樓園). Transformation focused on the spatial structure is divided into four periods based on literature. And reflect of landscape elements in defunct or unattributable records from tale and novel. The results were as follows. First, The beginning of Gwanghanllu pavilion(廣寒樓) was the composition of the Gwangtongnu Pavilion(廣通樓). The pavilion is located amid beautiful scenery such as the close-range view of a small stream, and distant view Jiri Mountain. Analysis of literature shows that Gwanghallu pavilion was in succession to Gwangtongnu Pavilion's landscape. Secondly, Gwanghallu(廣寒樓) pavilion represents the characteristic of the garden since 1582. Built the Samsinsan(三神山), Construct Lake and bridge that represents the galaxy for realization of utopia reflect in Taoist ideology. Thirdly, Gwanghalluwon garden was recovered when from Jeong-yu-jae-ran(丁酉再亂) to the Japanese Ruling Era. It took Gwanghalluwon garden a long while to recover from original form. According to records, Gwanghalluwon garden is still being likened to the landscape of fairyland by inheriting landscape in the previous of Jeong-yu-jae-ran(丁酉再亂). Fourth, By the modern times, Gwanghalluwon Garden has personality of tourist attractions. Until now, the area of the Gwanghalluwon garden has been expended during the processes of three times. Fifth, Aspect of landscape change of Gwanghalluwon is wide-spreading mainly Gwanghallu pavilion. But elements of external expansion in garden by introduced into the facility irrelevant to the authenticity of the garden. Sixth, Comprehension the cultural landscape of the garden are limited by deficient records. But, the main elements in the Gwanghalluwon garden are commonly appeared on imaginary environment within a tale and a novel. In addition, culture of garden at the time was depicted in tale and novel. In this sense, cultural landscape in garden was able to estimate through imaginary environment within novel.

• Korean Journal of Social Welfare
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• v.57 no.3
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• pp.73-103
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• 2005

This study takes of youth panel data(2002-2003), there is the purpose to know to youth employed's labor mobility conditions of employment status conversion and examine on factors affecting conversion of employment status. Main analysis result and policy imply, is as following. First, although youth employed's non-standard employment shows some decrease, employment youth hierarchy was construed that youth of our country is consisting very changefully because appear great turnover that is converted by unemployment or Not economically activity population same period. Specially, non-standard employment phenomenon of woman or low in scholarship person appeared notedly, and because phenomenon that is converted by unemployment or Not economically activity population is expose that is deepened, discriminating policy of government dimension is required for employment stabilization of these class. Second, show result that danger to escape to non-standard job risk trap which seeking employment activity of youth class is arranged case or company which is formed by official path is suitable becomes low, must formulate path of employment about youth class and improve qualitative level of employment through suitable job placement education of youth class or function (technology) level. Third, when was construed, but take into account that the although large enterprise have low risk in non-standard job, recently employment of youth class consists very limited, rather small scale business or smaller enterprise's competitive power preferably need to be plan. Finally, danger to non-standard job youth employed's company form is government connection wonder was expose that high, Such result can do that it is difficult by limited research period, but reflect actuality that youth unemployment policy of our country is enforced laying stress on public labor or unregular job employment such as internship system. Therefore, current youth unemployment policy may have to change by employment policy that can secure stable work record by youth class or act as bridge-building that promote conversion by full-time job.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.31 no.2
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• pp.103-117
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• 2013

This research analyzed the spatial components and establishment of the Tap-gol Park according to the plans between 1897 to 1916 when the discussions on the construction of the park began and it was accomplished as an urban park. The results are as follows. The establishment of Tap-gol Park can be divided by three period. Firstly, Tap-gol Park was owned by the royal family from 1987 to 1904. The discussions on construction of Tap-gol Park as a first urban park of Gyeongseong(京城) in 1897, and the private houses were tear down in order to secure land for the park in 1899. Gates and fences surrounding of Tap-gol Park were organized and it was opened in 1902 based on park plane of turtle - shaped. The octagonal pavilion for 'Lee-Wang-Jik musical band(李王職音樂隊)' was relocated in the southwestern part of the park in 1903. Secondly, Tap-gol Park was used actively by the public between 1910 to 1913, because it was opened for individuals. Also The boundary of Park were changed by surrounding facilities and recreational facilities and benefits was complemented for users. Tap-gol park was opened at nighttime in August 1913. Tap-gol Park was used as a place of amusement park. Thirdly, commercial facilities were made as the park facility between 1914 to 1916. The purpose of 'Kkikdajeom(喫茶店)' was similar to the one of modern cafes. It was built as a typical Japanese tea-house with a small pond having an island and a bridge constructed inside. With the increase of usage of Tap-gol Park as a recreational area by the citizens in 1916, the pavilion as a rest area and toilet as amenities were supplemented. Superintendent's office was equipped too. Simple chairs made from the wooden logs were installed around greenhouse, concert hall, the Wongaksa Buddhist temple(圓覺寺址十層石塔), and the flower garden was fenced round. After the relocation of Yongsan music band to Tap-gol Park, the existing concert hall was demolished. The shape of the park which was seen from the pictures of the magazines of 1920s were achieved as early as 1916. The importance of this research includes the basis to revise the errors of the preexistence researches and value of historical material of the design plan reference of the park which was accomplished during the Japanese colonial era. Also this research is to study on the spatial components of the modern landscape architecture and parks.