• Asian-Australasian Journal of Animal Sciences
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• 제27권12호
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• pp.1773-1782
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• 2014

The aim of the experiment was to study the effect of feeding system on meat quality characteristics of Small East African (SEA) goats and their crosses with Norwegian ($SEA{\times}N$) goats finished under small scale farming conditions. Twenty four castrated goats at the age of 18 months with live body weight of $16.7{\pm}0.54kg$ from each breed (SEA and $SEA{\times}N$) were distributed in a completely randomized design in a $2{\times}3$ factorial arrangement (two breed, and three dietary treatments). The dietary treatments were; no access to concentrate (T0), 66% access to ad libitum concentrate allowance (T66) and 100% access to ad libitum concentrate allowance with 20% refusal (T100) and the experimental period was for 84 days. In addition, all goats were allowed to graze for 2 hours daily and later fed grass hay on ad libitum basis. Daily feed intakes were recorded for all 84-days of experiment after which the animals were slaughtered. Feed intake of T100 animals was 536 g/d, which was 183 g/d higher than that of T66 group. Supplemented goats had significantly (p<0.05) better feed conversion efficiency. The SEA had higher (p<0.05) hot carcass weight (8.2 vs 7.9 kg), true dressing percentage (54.5 vs 53.3) and commercial dressing percentage (43.3 vs 41.6) compared to $SEA{\times}N$. There was no significant difference (p>0.05) for dressing percentage and carcass conformation among supplemented goats except fatness score, total fat depots and carcass fat which increased (p<0.05) with increasing concentrate levels in the diet. Increasing level of concentrate on offer increased meat dry matter with subsequent increase of fat in the meat. Muscle pH of goats fed concentrate declined rapidly and reached below 6 at 6 h post-mortem but temperature remained at $28^{\circ}C$. Cooking loss and meat tenderness improved (p<0.05) and thawing loss increased (p<0.05) with ageing period. Similarly, meat tenderness improved (p<0.05) with concentrate supplementation. Shear force of muscles varied from 36 to 66, the high values been associated with Semimembranosus and Gluteobiceps muscles. The present study demonstrates that there are differences in meat quality characteristics of meat from SEA goats and their crosses with Norwegian breeds finished under small scale farming conditions in rural areas. Therefore, concentrate supplementation of goats of both breeds improves meat quality attributes.

• 대한조선학회논문집
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• 제51권3호
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• pp.231-238
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• 2014

In this study, the self-propulsion tests are performed in INHA towing tank. And the effective wake characteristics of the KVLCC2 and the KCS models are compared by the experimental results. The form factor is independent of Reynolds number. To estimate the hydrodynamic performance of a full scale ship, the form factor is determined to consider attendant on Reynolds number. In this research, the power predictions are carried out considering the form factor difference of model and full scale ship. The results of this research could be used as one of the fundamental data to the powering performance prediction.

• Nuclear Engineering and Technology
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• 제53권10호
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• pp.3207-3216
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• 2021

Three-dimensional structures of a vortical flow field and heat transfer characteristics in a partially blocked 7-pin fuel assembly mock-up of sodium-cooled fast reactor have been investigated through a numerical analysis using a commercial computational fluid dynamics code, ANSYS CFX. The simulation with the SST turbulence model agrees well with the experimental data of outlet and cladding wall temperatures. From the analysis on the limiting streamline at the wall, multi-scale vortexes developed in axial direction were found around the blockage. The vortex core has a high cladding wall temperature, and the attachment line has a low cladding wall temperature. The small-scale vortex structures significantly enhance the convective heat transfer because it increases the turbulent mixing and the turbulence kinetic energy. The large-scale vortex structures supply thermal energy near the heated cladding wall surface. It is expected that control of the vortex structures in the fuel assembly plays a significant role in the convective heat transfer enhancement. Furthermore, the blockage plate and grid spacer increase the pressure drop to about 36% compared to the bare case.

• 한국측량학회지
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• 제19권2호
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• pp.199-208
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• 2001

우리나라의 수치지도제작은 축척에 따라 독립적으로 제작되어 활용되어 왔다. 따라서 다른 축척의 공간자료를 원할 경우 다시 제작해야 하기 때문에 막대한 시간과 경제적인 손실을 가져온다. 이러한 문제점을 해결하기 위한 방안으로 대축척 수치지도를 원시데이터로 하여 다양한 소축척 수치지도를 제작하기 위한 지도 일반화의 연구가 많이 진행되고 있다. 본 연구는 여러가지 일반화 처리 기법중 단순화에 의한 선형요소와 건물 레이어의 소축척 변환 특성을 연구하는데 그 목적이 있다. 이를 위하여 단순화 처리를 위한 알고리즘을 제시하였으며, 1:5,000수치지도로부터 1:25,000 수치지도로의 변환에 이를 적용, 수치지도의 단순화 특성을 분석하였다. 연구결과 면적분배 알고리즘이 Douglas-Peucker 알고리즘이나, Reumann-Witkam 알고리즘보다 건물의 최초면적과 형상을 잘 유지함을 알 수 있었다.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2001년도 춘계학술대회논문집E
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• pp.51-56
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• 2001

Vapor explosion is one of the most important problems encountered in severe accident management of nuclear power plants. In spite of many efforts, a lot of questions still remain for the fundamental understanding of vapor explosion phenomena. Therefore, KAERI launched a real material experiment called TROI using 20 kg of UO2 and ZrO2 to investigate the vapor explosion phenomena. In addition, a small-scale experiment with molten-tin/water system was performed to quantify the characteristics of vapor explosion and to understand the phenomenology of vapor explosion. A number of instruments were used to measure the physical change occurring during the vapor explosion. In this experiment, the vapor explosion generated by molten fuel water interaction is visualized using high speed camera and the pressure behavior accompanying the explosion is investigated.

• International Journal of Naval Architecture and Ocean Engineering
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• 제13권1호
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• pp.57-64
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• 2021

Maneuvering motions of a ship in calm water are studied through the concept of MMG model. Governing forces are defined by the use of available empirical formulae that require only main ship particulars as input variables. In order to validate the calculation tool, a full-scale sea experiment was carried out in Osaka Bay using a 17-m twin-screw passenger ferry. Test execution and data measurement were performed through the utilization of an autopilot control unit and satellite compass. The result of a straight running test confirms the acceptable accuracy in addressing the surge motion problem. Reasonable agreement between simulation and experiment is also confirmed for 5°/5° and 10°/10° zig-zag tests despite the strong environmental disturbance. The current model can generally represent the subject ship maneuvering motions and is promising for the application to other ship hulls.

• 한국과학교육학회지
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• 제27권4호
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• pp.318-327
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• 2007

본 연구의 목적은 고등학교 화학II 교과에서 Small Scale Chemistry(SSC)를 적용한 수업이 학생들의 과학 탐구 능력과 과학관련 태도에 미치는 효과를 알아보는데 있다. 연구 대상은 인문계 고등학교 3학년 학생 112명이며, 실험 집단과 비교 집단으로 나누었다. 화학II 교과서의 기존 실험을 대치할 수 있는 SSC 실험을 7개 선정하여 이를 실험 집단에 적용하고, 비교 집단에는 교과서에 제시된 기존 실험을 적용하였다. 연구 결과 두 집단 간에 과학 탐구 능력의 향상에는 유의미한 차이가 있었으나, 과학관련 태도의 향상에는 유의미한 차이가 없었다. 세부 분석 결과 과학 탐구 능력의 차이는 기초 탐구 능력의 차이에 의한 것으로 나타났다. 실험 집단 학생들은 SSC 실험이 기존 실험에 비해 많은 장점(예를 들면, 개별 실험, 실험과 이론의 동시 학습, 짧은 실험 시간, 안전성, 친환경성 등)이 있음을 인식하고 있었다. 이러한 결과는 고등학교 화학 과목에 SSC 실험을 적용할 가치가 있음을 나타내며 현 교과서의 기존 실험을 대치할 수 있는 다양한 SSC 실험을 개발하여 보급할 필요가 있음을 시사한다.

• 한국측량학회지
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• 제17권2호
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• pp.97-104
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• 1999

수치표고모델(DEM)은 정사영상 제작을 위한 중요한 기초 자료이며, 품질은 대상 점 또는 선형요소의 기하학적 정확도에 의존하게 된다. 따라서 본 연구에서는 격자의 간격과 스캐닝 해상도를 달리하며 상관매칭에 의해 수치표고모델 생성을 시도하였다. 실험결과 추출점의 격자간격이 작을수록 표준편차가 가장 작게 나타났으며 스캐닝의 해상도는 큰 영향이 없는 것으로 나타났다. 또한 수치표고모델에 대한 편이량 분석결과 소축척에 비해 대축척의 항공사진에서 편이가 크게 발생되었으며 이는 폐쇄영역이 가장 큰 영향 요소임을 알 수 있었다. 이러한 패쇄영역을 줄이기 위하여 다축척 영상의 이용과 종 중복도를 증가시키며 실험한 결과 한 쌍의 입체영상보다 다중영상을 이용한 경우 음영 및 폐쇄영역의 크기를 대폭 감소시킬 수 있는 것으로 나타났다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1996년도 하계학술대회 논문집 A
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• pp.431-433
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• 1996

It is expected that utility interactive small scale dispersed PV system will be widely diffused in the future. This paper discussed the design and control method of single phase PV inverter system with compensation capability of reactive power including harmonic distortion, based on state space modelling. As the results, compensation effects were suggested by simulation and experiment.

• 한국화재소방학회:학술대회논문집
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• 한국화재소방학회 1997년도 International Symposium on Fire Science and Technology
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• pp.66-76
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• 1997

In order to investigate the generation of carbon monoxide and heat loss of incomplete combustion in compartment fires, an experiment was conducted in a small scale compartment by using methanol as a fuel. The concentration of carbon monoxide and the toxicity parameter showed high values when the mass air - to - fuel stoichiometric ratio is under 1.0. The constitution of the combustion gas was showed to estimate it from the . The heat loss due to incompleteness of combustion is about one third of heat of combustion in case of under 1.0.