• 대한기계학회:학술대회논문집
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• 대한기계학회 2000년도 춘계학술대회논문집B
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• pp.276-281
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• 2000

A simulation program using the mass transfer correlation was constructed to analyze 1-D simplified condensing flow across the tube bank. Higher efficiency was anticipated by reducing the flue gas temperature down below the dew point where the water vapor in the flue gas is condensed at the surface of the heat exchanger; that is, the heat transfer by the latent heat is added to that by the sensible heat. Thus, there can be an optimum operating condition to maximize the heat recovery from the flue gas. The temperature rises of the flue gas and the cooling water between the inlet and the outlet of the tube bank were compared with the experimental data reported previously. The predicted results agree well with the experimental data. Using this simulation program, the parametric studies have been conducted fur various operating conditions, such as the velocities and temperatures of the vapor/gas mixture and the cooling water, the number of the rows, and the conductivity of the wall material.

• 대한기계학회논문집B
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• 제41권10호
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• pp.659-665
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• 2017

본 연구에서는 엇갈림 배열 관군 사이를 전기 전도성 유체가 흐를 때 외부에서 인가한 자기장의 영향으로 변화하는 열유동 특성을 수치해석적으로 연구하였다. Reynolds 수 50과 100의 비정상 층류 관군 유동에서 외부 인가 자기장의 세기를 의미하는 Hartmann 수를 0에서 100까지 점진적으로 변화시킴에 따라 관군 내부의 열유동 특성을 관찰하였다. Hartmann 수가 증가함에 따라 인가 자기장의 영향으로 관표면의 속도 경계층이 얇아지고, 유동 박리를 후류로 지연시키며, 관 후면에 형성되는 재순환 영역의 크기가 줄어드는 것을 관찰하였다. 최종적으로 열유동 변형에 의한 결과적 국소 및 평균 Nusselt 수 변화 특성을 제시하였다.

• 한국농공학회지
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• 제24권2호
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• pp.49-55
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• 1982

The purpose of this study is to classify the factors influenced on the damages of head works suffered from the storm flood occurred on July 22 1980 in both Musim and Bochong rivers and to find out an integral counter measures against the causes influenced on the disaster of head works in the engineering aspect of planning, design, construction and maintenance. In this survey, number of samples was taken 25 head Works, and the counter measures against the causes of their disasters summarized was as follows, 1. In the aspect of planning a. As the flood water level after the establishment of head works is more increased than the level before setting of head works owing to having more gentle slope of river bed between the head works than nature slope of river bed. Number of head works should be reduced for the appropriate annexation of them b. In the place where head works is established on the curved point of levee, the destruction of levee becomes severe by the strong deflective current. Therefore the setting of head works on the curved point should be kept off as long as possible and in case of unavoidable circumstances the construction method such as reinforced concrete wall or stone wall filed with concrete and anchored bank revetments should be considered. 2. In the aspect of design a. As scoring phenomena at up stream is serious around the weir Where the concentration of strong current is present in such a place, up stream apron having impermeability should be designed to resist and prevent scoring. b. As the length of apron and protected bed is too short to prevent scoring as down stream bed, the design length should be taken somewhat more than the calculated value, but in the case the calculated length becomes too long to be profitable, a device of water cushion should be considered. c. The structure of protected river bed should be improved to make stone mesh bags fixed to apron and to have vinyl mattress laid on river bed together with the improvement for increasing the stability of stone mesh bags and preventing the sucked sand from the river bed. d. As the shortage of cut-off length, especialy in case of the cutoffs conneting both shore sides of river makes the cause of destruction of embankment and weir body, the culculation of cut-off length should be taken enough length based on seepage length. 3. In the aspect of design and constructions a. The overturing destruction of weir by piping action was based on the jet water through cracks at the construction and expansion joints. therefore the expansion joint should be designed and constructed with the insertion of water proof plate and asphalt filling, and the construction joint, with concaved shape structure and steel reinforcement. b. As the wrong design and construction of the weep holes on apron will cause water piping and weir destruction, the design and construction of filter based on the rule of filter should be kept for weep holes. c. The wrong design and construction of bank revetment caused the severe destruction of levee and weir body resulting from scoring and impulse by strong current and formation of water route behind the revetment. Therefore bank revetment should be designod and constructed with stone wall filled with concrete and anchored, or reinforced concrete wall to prevent the formation of water flow route behind the wall and to resist against the scoring and impulse of strong stream. 4. In the aspect of maintenance When the damaged parts occurred at head works the authorities and farmers concerned should find and mend them as soon as possible with mutual cooperation, and on the other hand public citizen should be guided for good use of public property.

• 보존과학회지
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• 제28권4호
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• pp.411-416
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• 2012

이 연구의 목적은 백제 풍납토성 화재주거지(라-8호)에서 출토된 탄화목의 방사성탄소연대 분석을 통하여 풍납토성의 축조연대를 규명하는 것이다. 탄화목에서 10년 간격으로 채취된 6개의 연륜에 대한 방사성탄소연대를 위글 매치한 결과, 최외각 연륜의 ${\pm}2{\sigma}$ 연대(95.4% 신뢰구간)가 A.D. 190~280년으로 산출되어 이 주거지가 3세기 초중반에 형성된 것을 알 수 있었다. 이 연대는 주거지형태와 토기양식으로 추론된 고고학적 편년과 일치되는 결과이다.

• 박물관보존과학
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• 제22권
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• pp.41-52
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• 2019

부여 능산리 서고분군 1, 2호분의 석실내부 벽화의 존재 여부를 확인하기 위하여 육안조사와 현장에서의 현미경 관찰, 형광X선분석을 수행하고, 일부 채취 시료에 대한 X선회절분석을 수행하였다. 그 결과, 1호분은 석벽의 표면 마무리 상태가 거칠고, 현실 천정을 제외한 부위에서는 벽화의 어떠한 흔적도 관찰되지 않았다. 또한 현실 천정에서는 석재와는 다른 색의 흑색 물질이 관찰되는데, 이 부분의 경우에도 표면부와 표면을 살짝 긁어내어 드러난 내부가 동일한 육안적 특징을 보이며, 이 부분에서 채취한 시료에서 흑운모가 주된 광물로 동정되어 먹 등 인위적 물질을 칠한 것이 아니라 석벽의 구성광물인 것으로 확인되었다. 2호분의 경우 내부 동, 서, 북의 석벽 표면에서 백색물질이 관찰되며, 이 물질에 대한 분석 결과 석회(Calcite)로 확인되어 벽화의 존재가 의심되었다. 그러나 석회층이 동벽의 현실입구와 연도부분에 집중되어 있으며, 북벽과 서벽의 경우에는 단지 하부에서만 집중적으로 관찰되었다. 또한 동벽의 현실입구와 연도부분의 석회물질은 그 분포 형태가 도굴 갱으로 유입된 흙이 쌓인 흔적과 상응하고 있어 2호분 내벽의 석회물질은 외부의 흙과 석회가 유입되어 형성된 것으로 판단되었다. 또한 천장과 사면의 석판틈새에서 확인되는 메움 물질은 분석결과 니질의 토양으로 석벽 표면에 존재하는 석회와는 다른 물질로 확인되었다. 만약 벽화를 조성할 목적으로 석벽표면에 석회층을 인위적으로 형성한 것이라면 석판틈새 매움 물질도 석회를 사용하는 것이 더 자연스러웠을 것이다. 이러한 점으로 보아 능산리 2호분의 현실과 연도의 내벽에도 벽화는 없는 것으로 판단된다.

• 한국실내디자인학회:학술대회논문집
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• 한국실내디자인학회 2005년도 춘계학술발표대회 논문집
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• pp.251-252
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• 2005

The present design, which is English Zone Development Project for 'G' Elementary School at Seo gu, Incheon, contained various booths for experiential learning corners as well as spaces of teaching learning through group study, dramas and role plays, breaking away from the structure and atmosphere of traditional language labs, and at the same time it include a school building as an affiliated space where the whole students can gather for discussion and learning. The general design concept adopted the atmosphere of an exotic street, installing five theme booths (airport, bank, hospital, book/game store and shop) along the wall and applying the image of road to the floor in order to perform role plays. The blackboard and furniture were also designed to produce the atmosphere of street so that elementary students take interest and actively participate in learning.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2003년도 Proceedings of ACRS 2003 ISRS
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• pp.444-446
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• 2003

Mogao Grottos are located at the eastern foot of the Mingsha Mountain, 25km southeast of Dunhuang City. The caves were excavated into the cliff on the west bank of the Daquan River. The wall paintings in the caves are subject to the severe deterioration generated by recrystallization of salt. It relates with the movement of water/moisture in rock formation. Through the satellite image analysis and geological survey it has been clarified that the movement of ground water is governed by the fault system. The geographical nature is specified by the aggressive tectonic movement from the south.

• 한국동물번식학회:학술대회논문집
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• 한국동물번식학회 2001년도 춘계학술발표대회
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• pp.5-5
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• 2001

This study was to test whether Hanwoo in vitro matured oocytes can be successfully cryopreserved by a new vitrification procedure using MVC method. For the vitrification, oocytes were pretreated in 10% ethylene glycol (EG10) for 5-10 min, exposed in EG30 for 30 sec, each oocytes were individually put on the inner wall of 0.25 $m\ell$ straw, and then straws were directly plunged into L$N_2$. Thawing was taken by 4-step procedures [1.0 Msucrose (MS), 0.5 MS, 0.25 MS, and 0.125 MS] at 37$^{\circ}C$. In vitro developmental capacity (survival, cleavage ($\geq$2-cell) and blastocyst rates) in vitrified group was no significant difference compared to that in other treatment groups (exposed; 100.0, 74.4, 32.3% and control; 100.0, 78.3, 36.3%): high mean percentage of oocytes (91.2%) was survived, 69.4% of them were cleaved and 27.9% of cleaved embryos were developed to blastocyst. Especially, after transfer of in vitro developed embryos in vitrified group, four of six recipient animals were found to pregnant and three of them were ongoing pregnant by manual palpation at 250 days after transfer. However, among them, two healthy female calves (23 and 25kg) were born. This result demonstrates that MVC method is very appropriate freezing method for the Hanwoo in vitro matured oocytes and that ovum bank can be maintained efficiently by MVC cryopreservation method.

• Parasites, Hosts and Diseases
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• 제53권5호
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• pp.545-551
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• 2015

Schistosomiasis is one of the important neglected tropical diseases (NTDs) in Tanzania, particularly in Lake Victoria zone. This baseline survey was a part of the main study of integrated control of schistosomiasis and soil-transmitted helminths (STHs) aimed at describing morbidity patterns due to intestinal schistosomiasis among adults living on Kome Island, Sengerema District, Tanzania. Total 388 adults from Kome Islands (about 50 people from each village) aged between 12 and 85 years, were examined by abdominal ultrasound according to the Niamey protocol. Liver image patterns (LIPs) A and B were considered normal, and C-F as distinct periportal fibrosis (PPF). The overall prevalence of PPF was 42.2%; much higher in males than in females (47.0% in male vs 34.4% in females, P=0.007). Abnormal increase of segmental branch wall thickness (SBWT) and dilated portal vein diameter (PVD) were also more common in males than in females. Hepatosplenomegaly was frequently encountered; 68.1% had left liver lobe hepatomegaly and 55.2% had splenomegaly. Schistosoma mansoni-related morbidity is quite high among adults in this community justifying the implementation of integrated control strategies through mass drug administration, improved water supply (pumped wells), and health education that had already started in the study area.

• 인터넷정보학회논문지
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• 제25권1호
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• pp.57-67
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• 2024

본 연구는 금융 분야에서 중요한 증감 정보를 효과적으로 이해하고 감성을 정확하게 분류하기 위한 언어 모델의 학습 방법론을 탐구한다. 연구의 핵심 목표는 언어 모델이 금융과 관련된 증감 표현을 잘 이해할 수 있게 하기 위한 적절한 데이터 세트를 찾는 것이다. 이를 위해, Wall Street Journal에서 수집한 금융 뉴스 문장 중 증감 관련 단어를 포함하는 문장을 선별했고, 이와 함께 적절한 프롬프트를 사용해 GPT-3.5-turbo-1106으로 생성한 문장을 각각 post-training에 사용했다. Post-training에 사용한 데이터 세트가 언어 모델의 학습에 어떠한 영향을 미치는지 금융 감성 분석 벤치마크 데이터 세트인 Financial PhraseBank를 통해 성능을 비교하며 분석했으며, 그 결과 금융 분야에 특화된 언어 모델인 FinBERT를 추가 학습한 결과가 일반적인 도메인에서 사전 학습된 모델인 BERT를 추가 학습한 것보다 더 높은 성능을 보였다. 또 금융 뉴스로 post-training을 진행한 것이 생성한 문장을 post-training을 진행한 것에 비해 전반적으로 성능이 높음을 보였으나, 일반화가 더욱 요구되는 환경에서는 생성된 문장으로 추가 학습한 모델이 더 높은 성능을 보였다. 이러한 결과는 개선하고자 하는 부분의 도메인이 사용하고자 하는 언어 모델과의 도메인과 일치해야 한다는 것과 적절한 데이터 세트의 선택이 언어 모델의 이해도 및 예측 성능 향상에 중요함을 시사한다. 연구 결과는 특히 금융 분야에서 감성 분석과 관련된 과제를 수행할 때 언어 모델의 성능을 최적화하기 위한 방법론을 제시하며, 향후 금융 분야에서의 더욱 정교한 언어 이해 및 감성분석을 위한 연구 방향을 제시한다. 이러한 연구는 금융 분야 뿐만 아니라 다른 도메인에서의 언어 모델 학습에도 의미 있는 통찰을 제공할 수 있다.