• Proceedings of the Korean Institute Of Construction Engineering and Management
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• autumn
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• pp.301-304
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• 2001

The purpose of this study is presume that reasonable construction period of constract and appropriate number of persons for works according to reconstruction. This study is presume reasonable construction period of constract and appropriate number of person of reconsruction with a case study out of apartment R.C construction. The result of this study are as follows: 1. In case of four building of apartment Resonable constrution period: 750days$\sim$800days, the average(1day) number of persons under working: 63.5 persons. 2. In case of four building of apartment Resonable constrution period: 850days$\sim$900days, the average(1day) number of persons under working: 100.6 persons. 3. In case of four building of apartment Resonable constrution period: 1000days$\sim$1050days, the average(1day) number of persons under working: 145.0 persons.

• Proceedings of the Korea Water Resources Association Conference
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• 2016.05a
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• pp.67-67
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• 2016

최근 기후온난화로 인한 이상기후와 지진의 발생가능성으로 인해 직렬 혹은 병렬로 위치한 2개 이상의 댐(저수지)들의 연속 붕괴 가능성도 점점 커지고 있어 연속 댐 붕괴에 대한 비상대처계획도 수립에 대한 관심도 증대되고 있다. 국내에서는 댐(저수지) 붕괴로 인한 극한홍수해석이나 비상대처계획 수립시 국내에서는 DAMBRK, FLDWAV, HEC-RAS와 같은 1차원 수리동역학 모형이 주로 사용되어지고 있다. 하지만 1차원 모형은 흐름을 하나의 방향으로만 한정하여 해석하고, 각각의 적용 횡단면에서 동일 수위를 가지다는 가정으로 홍수범람해석을 수행하므로 정확성뿐만 아니라 실제 적용성에서도 한계를 가질 수밖에 없다. 댐(저수지) 붕괴로 인한 홍수범람해석에서 2차원 이상의 고차원 모형은 앞서 언급한 1차원 모형에 적용된 비현실적인 가정을 포함하지 않으므로 더욱 정교하고 신뢰성 있는 결과를 얻을 수 있다. 하지만, 홍수범람해석을 위한 상용 프로그램들은 단일 댐(저수지) 붕괴의 적용에는 큰 어려움이 없으나, 지형단면을 초기에 한번만 고려하는 문제로 인하여 연속 댐(저수지) 붕괴의 고려에는 한계를 가진다. 따라서 본 연구에서는 댐(저수지)의 연속 붕괴를 해석할 수 있는 2차원 수리동역학 모형을 개발하고자 한다. 각 댐(저수지)의 붕괴 전과 후의 지형 단면을 여러 번 반영할 수 있는 모형을 개발함으로써 시간차를 두고 붕괴되는 댐(저수지)의 연속 붕괴를 해석할 수 있도록 하였다. 개발모형은 2002년 태풍 루사로 인해 실제로 붕괴된 저수지에 적용되었으며, 이 저수지들은 붕괴시 시간차이를 두고 붕괴가 이루어져 개발모형의 적용 유역으로 선택하였다. 저수지의 연속붕괴 모델링을 위해 지형자료로는 저수지 단면, 댐 제체 및 여수로 붕괴 단면, 하천 단면 그리고 홍수터 지형 반영을 위한 수치지도, 경계조건으로는 저수지로의 유입유량과 하류단 조위조건이 고려되었다. 그리고 태풍 루사 당시의 기록적인 강우를 반영하기 위해 연구유역 인근에 관측된 강우를 모형에서 하천 및 홍수터에서 고려할 수 있도록 하였다.

• The Journal of Korean Academy of Prosthodontics
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• v.58 no.1
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• pp.23-29
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• 2020

Purpose: The purpose of this retrospective study was to evaluate the method using the S-reamer and gel-type graft material by the success rate and survival rate. Materials and methods: Implantation period was from 2008 to 2014, Follow check up year is 2019. There were 59 patients and 117 implants. All implants were placed in the posterior maxilla with the sinus lift. The patients population consisted of 34 men and 25 women, ranging from 19 to 75 years. The residual bone heights were from 1 mm to 6 mm. Sinus was perforated with S-reamer without membrane tearing and gel type bone graft material was used for membrane lifting and filling the space. all implants were placed simultaneously. Panoramic X-ray was taken. After 5 - 6 months healing period, final prostheses were restored. After more 5-years implant surgery, Panoramic X-ray was obtained and X-ray analysis and clinical examination were performed. Success criteria was referred to a Buser's success critera. All implants were classified to success implant, survival implant, failed implant. A success implant was satisfying success criteria, a survival implant was a implant that was acute infection with suppuration and bone loss, a failed implant was a implant that was mobile, removed. Results: Five implants were removed, and 4 implants had infected with bone loss. Survival rate was 95.7% and success rate was 92.3%. Conclusion: This retrospective study presented that this method with S-reamer and gel-type graft material was a successful treatment without membrane tear in the condition of 1-6 mm residual bone height.

• Journal of Digital Contents Society
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• v.16 no.1
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• pp.137-144
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• 2015

This study tried to anticipate the near future changes of domestic online video, music service and media usage through the status quo. The research group was focused on the twenties, University students because they are the active media contents users. It surveyed the students in Busan, and used the method of descriptive statistics analysis for the understanding of the present state and near future prospect. This study shows that almost half of them use both services, and three people out of ten are the heavy users who use the services for over 3 hours a week. The streaming method is higher proportion than download method in using type. They are getting accustomed to pay contents cost, but it couldn't be said the paying content cost has been established. Preferred contents genre appears to be the RMC(Ready Made Contents) such as existing broadcaster contents and movies. Notable result on media usage was the proportion of the so-called 'Zero-TV'. It was 32%, significantly higher than the proportion of the total population(4.4%). Integrating the analysis results, we can expect that the usage pattern will be changed gradually, thus the advent of various revenue models will emerge.

• Journal of the Korean Recycled Construction Resources Institute
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• v.3 no.3
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• pp.268-276
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• 2015

In this study, $CO_2$ reduction type quaternary component high fluidity concrete was produced with more than 80% reduction in cement quantity to increase the use of industrial byproducts and enhance construction performance, thereby reducing $CO_2$ emissions. Furthermore, the quality properties, and $CO_2$ reduction performance of this concrete were evaluated. As a result of the quality evaluation of quaternary component blended high fluidity concrete with $CO_2$ reduction, the target performance could be achieved with a 80% or more reduction of cement quantity by mixing a large amount of industrial byproducts. The required performance level was obtained even though the flow, dynamic, and durability characteristics decreased a little compared to conventional mix. In addition, to analyze the $CO_2$ reduction performance of quaternary component blended high fluidity concrete with $CO_2$ reduction, the life cycle assessment (LCA) of the concrete was performed and the results showed that compared to the conventional mix, the carbon emissions decreased by 62.2% and the manufacturing cost by 24.5%.

• Korean Journal of Head & Neck Oncology
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• v.3 no.1
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• pp.65-70
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• 1987

하인두암은 거의 대부분 이상동(Pyriform Sinus) 에서 발생하며 상당한 정도 진행 시까지 별다른 증상을 나타내지 않는다. 저자들은 1966년부터 1985년까지 만 20년간 하인두에서 발생된 암환자 63명을 중심으로 임상 관찰 및 문헌고찰과 함께 발표하는바이다. 원발병소로는 전체 중 58명에서 이상동, 하인두벽(hypopharyngeal wall) 3명, Postcricoid hypopharynx 와 pharyngopalatine fold 에서 각각 1명씩의 발생빈도를 보였다. 저자들은 설저(base of tongue)암, supraglottic Ca. 및 경부 식도(cervical esophagus)암 경우는 모두 제외시켰다. 임상증상으로서는 경부 종괴(lump)가 33 예로써 가장 현저했으며 또한 첫증상으로써 연하곤란(dysphagia) 또는 sore throat를 나타낸 경우는 32 예 이었다. 그 외에 hoarseness 가 20 예, bloody sputum 4 례 및 호흡곤란 2 예의 순이었다. 내원까지의 증상기간은 대부분 $4{\sim}6$ 개월 이었다. 흡연관계는 1일 1값 이상의 중등도 흡연 경우는 전체의 58% 이었으며 흡연 사실이 있었던 경우는 전체의 88% 이었다. 연령별 발생빈도는 50대$\sim$60대에서 48명으로서 현저히 높았다. 완치 목적의 수술적 치료는 24명에서 시행하였으며 치료 거절은 16명이었다. 치료 거절하였던 환자들 중 81% 가 임상적 제 4 병기였으며 보조적 치료 요법을 실시한 환자들의 78% 에서 제 4 병기였다. 또한 완치 목적의 치료 실시 경우의 67% 에서 제 4 병기였다. 수술요법은 일반적으로 "후두 인두 적출술 및 양측 경정맥 임파군 곽청술"(laryngopharyngectomy with bilateral jugular dissection) 또는 후두 인두 적출술 및 동측의 표준 광범위 경부 곽청술(standard radical neck dissection) 과 반대측의 경정맥 임파군 곽청술을 시행하였다. 3 년 이내와 3 년 이상무병 상태(free of disease) 경우가 각각 4명씩이었다. 마지막 예후 추적 조사시까지 무병 상태였던 환자를 포함하여 예후 추적 조사기간 중 추적 실패 경우는 7명이었다. 확정된 3 년 생존율(determinate 3-year survival rate) 은 31% 이었다. 수술 사망이 1명 있었으며 재발경우는 9 명이었다. 재발부위로는 원발병소 재발이 7명, 경부 재발 1명 및 원격전이가 1명 이었으며, 저자들은 이에 대한 실패 원인을 규명코져 하였다.

• Journal of the Korea Society of Computer and Information
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• v.16 no.2
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• pp.71-81
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• 2011

In order to easily create video tutorials, the algorithm is needed that video camera recording, white board images, video attachments, and document data are combined in real-time. In this study, we implemented the video lecture content creation system using wavelet-based lossless compression to composite multimedia objects in real-time and reproduce the images. Using commercially available PC can be useful when lecturers want to make video institutional contents, it can be operated easily and fastly. Therefore, it can be very efficient system for e-Learning and m-Learning. In addition, the proposed system including multimedia synthesis technology and real-time lossless compression technology can be applied to various fields, different kinds of multimedia creation, remote conferencing, and e-commerce so there are highly significant.

• Journal of the Korea Concrete Institute
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• v.20 no.6
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• pp.773-784
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• 2008

Even if the exploitation of copper slag produced during the smelting process of copper as aggregate for construction purpose has been permitted since 2004 in Korea, the lack of sufficient data enabling to evaluate its long-term stability that is its durability has to date impeded its application. This study intends to investigate experimentally the durability characteristics of 18 and 27 MPa-class commercial concretes in which natural sand (fine aggregates) has been partially replaced by copper slag through accelerated and exposure tests so as to provide bases promoting the application of copper slag concrete. The experimental results revealed insignificant difference of the durability characteristics in most of the mix proportions in which 30% of natural sand was replaced by copper slag. In the case where crushed sand was adopted, tests verified similar characteristics for replacement ratio of 50%. Particularly, the results of the exposure test conducted during 8 years demonstrated that equivalent level of durability was secured compared to the case using natural sand. In the case of 18MPa-class lower grade concrete, exposure test verified also that the physical lifetime similar to 50 years could be secured until carbonation reaches cover depth of 20 mm.

• Economic and Environmental Geology
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• v.49 no.2
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• pp.97-104
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• 2016

Here we firstly present that a timing of reactivated event of Yangsan fault, the major fault in the southeastern Korean Peninsula, by using combined approaches of the optimized illite-polytype quantification, the K-Ar age-dating, and the recently developed illite-age-analysis (IAA) approach for the fault clays from Sangcheon-ri area of Yangsan main fault line. Two chronological record of brittle fault-activation event at about 41.5~43.5 and 50.7 Ma were determined from 3 fault gouges suggesting a crucial reactivation time-scheme. Furthermore, the regional processes that drive tectonics to form and reactivate the Yangsan fault may be explained from the chronological analysis for additional sites along the Yangsan fault.

• Journal of Convergence for Information Technology
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• v.10 no.7
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• pp.249-256
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• 2020

To investigate the natural cosmetic ingredients of Benincasa hispida seed extract on skin care, we measured anti-oxidant and anti-inflammatory, and whitening effect. DPPH free radical scavenging activity was increased in a dose-dependent manner. The total phenolic content was higher in methanol extract (22.42±0.002 mgGAE/g) than water extract (9.77±0.002 mgGAE/g). MTT assay was demonstrated that the seed extract did not have a cytotoxic effect in RAW264.7 and B16F10 cell lines. We also examined to find out the inhibitory activity on NO production and secretion of TNF-α cytokine in LPS-induced RAW264.7 cells. In B16F10 melanoma cells, the seed extract significantly suppressed α-MSH induced melanin synthesis. Furthermore, westernblot analysis revealed that methanol extract dramatically downregulated the expression level of MITF, TRP-1 and TRP-2. Taken together, the B. hispida seed extract posses anti-oxidant, anti-inflammatory and skin whitening activities, which might provided its functional efficacy in cosmetic materials.