• Korean Journal of Food Science and Technology
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• v.52 no.5
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• pp.555-559
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• 2020

In order to examine the toxicity of palatinose-L (Pal-L) bioconverted from sucrose, we performed a 14-consecutive day toxicity study with male and female Sprague-Dawley (SD) rats. We recorded clinical signs of toxicity, body weight, organ weights, hematology, blood biochemical, urinalysis, histological changes in organs, such as the liver and kidneys, and clinical chemistry analysis data for all SD rats. There were no significant changes in food/water consumption, body weight, and organ weights during the experimental period. Although there were some hematologic and urinalysis alterations, these changes were not considered toxicologically significant. In addition, histopathological examination of the liver and kidneys revealed no abnormal or toxicological changes between the control and Pal-L-treated rats of both sexes. Collectively, these results suggest that Pal-L was not indicated to have any toxicity in the SD rats when it was orally administered up to a dose of 1,000 mg/kg/day for 14 days.

• Korean Journal of Poultry Science
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• v.33 no.2
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• pp.159-164
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• 2006

To investigate the effects of salt contents in diet and water on the growth of broiler chicks, 288 heads of Hubbards strain chicks, were fed with com-soybean meal diets containing 0, 0.25, 0.5, 0.75 1.0, 2.0, 3.0, or 4.0% salt from 1d to l4d posthatching. And 180 chicks were also supplemented with salt to their water at 0, 0.1, 0.2, 0.5 or 1.0%. Feed intake and weight gain tended to decrease as the salt levels in diets increased and those were the lowest in 4% group as 481 g and 168 g, however, mortality was the highest in 4% group as 75.0%. As for the salt levels in water, feed intake and weight gain were low as 427 g and 162 g in 1% group, while mortality was 77.8%. Salt poisoning chicks were shown with thirsty, appetite deficiency, rising impossibility, sleepiness, or convulsions, and in autopsy, were shown with ascites, hydropericardium, cardiac hypertrophy, hemorrhage of eyelid, hemorrhage of trachea, hemorrhage of intestine, etc. Conclusively, salt content above 4% in diet or 1% in water could reduce the performance in broiler chicks.

• Korean Journal of Food Science and Technology
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• v.37 no.6
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• pp.989-996
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• 2005

Ultraviolet (UV) induces photo aging, erythema, sunburn, photo-toxicity, photo-allergy, and skin tumor, To investigate photo-protective effects of AmorePacific Beauty-03 (APB-03; mixture of red ginseng extract powder and soybean extract powder) on UV-induced damaged skins, 40 SKH hairless female mice were orally administered APB-03 or saline five times a week and irradiated with UV three times per week far up to 12 weeks. Visible skin changes and skin damage in dermis and epidermis by replica image analysis and histological analysis. In APB-03-treated group, better skin, negative replica appearance and less wrinkle formation were observed compared to the UV control group. These results demonstrate oral administration of APB-03 have photo-protective effects on UV-damaged hairless mouse skin.

• Journal of the Korea institute for structural maintenance and inspection
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• v.21 no.1
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• pp.9-14
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• 2017

In the present work, a mechanical performances under cyclic loading in RC (Reinforced Concrete) beams with normal steel and FRPH (Fiber Reinforced Plastic Hybrid) bar are investigated. For the work, RC beam members with $200{\times}200{\times}2175mm$ of geometry and 24 Mpa of design strength are prepared, and 4-point-bending tests are performed for evaluation of cracking, yielding, and ultimate loads. Through static loading test, 48.9kN and 36.0 kN of yielding loads are measured for normal RC and FRPH beam, respectively. They have almost same ultimate load of 50.0 kN. Typical tension hardening behavior is observed in FRPH beam, which is caused by the behavior of FRPH bar with tension hardening. In cyclic loading conditions, FRPH beam has more smaller crack width and scattered crack pattern, and it shows more elastic recovery than normal RC beam. The energy dissipation ratio in FRPH beam is 0.83, which is greater than 0.62 in normal RC beam and it shows more effective resistance to cyclic loadings.

• Geophysics and Geophysical Exploration
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• v.12 no.4
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• pp.328-337
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• 2009

To investigate the relation between pore fluid conductivity and bulk resistivity of a rock sample it is assumed that electrolyte solution perfectly substitute the pore fluid that occupied the pore space within the sample in general. In this study, it is investigated that how much can the electrolyte solution substitute the pore fluid by repeating the same saturation process. Four kinds of NaCl solutions of 8, 160, 3200, 64000 ${\mu}S$/cm are used. The saturation process has repeated four times for each electrolyte in increasing conductivity order first then four times each in decreasing order. The more the saturation process repeated with the same electrolyte, the more electrolyte solution substitute the pore fluid. Geometric mean of bulk resistivity in increasing and decreasing orders with the same electrolyte solution is assumed to be mostly close to the bulk resistivity with perfect substitution. Bulk resistivity measurements for both increasing and decreasing order differs within 10% to the geometric mean when repeating the saturation process 4 times while maximum 40% difference is observed when single saturation process for each electrolyte solution with increasing order. The modified parallel resistant model can generally represent the relations between pore fluid resistivity and bulk resistivity in the experiment, but more experimental data with various rock samples with different porosity is needed to generalize the model.

• Journal of the Korean Geotechnical Society
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• v.33 no.2
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• pp.17-26
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• 2017

Pile foundations that support offshore structures or transmission towers are dominantly subjected to cyclic lateral loads due to wind and waves, causing permanent displacement which can severely affect stability of the structures. In this study, a series of cyclic lateral load tests were conducted on a pre-installed aluminum flexible pile in sandy soil with three different relative densities (40%, 70% and 90%) in order to evaluate the permanent displacement of a cyclic laterally loaded pile. Test results showed that the cyclic lateral loads accumulated the irreversible lateral displacement, so-called permanent displacement. As the number of cyclic lateral load increased, accumulated permanent displacement increased, but the permanent displacement due to one loading cycle gradually decreased. In addition, the permanent displacement of a pile increased with decrement of relative density and decreased by soil saturation. From the test results, the normalized permanent displacement defined as the cumulative permanent displacement to the initial permanent displacement ratio was investigated, and empirical equations for predicting the normalized permanent displacement was developed in terms of relative density of the soil and the number of cyclic lateral load.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 2004.05a
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• pp.676-680
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• 2004

성공적인 제품개발을 위해서는 효과적인 평가가 필수적이다. 이러한 제품평가를 위해 여러 가지 신뢰성 시험이 실시되고 있으며 시간에 따라 특성치의 열화를 평가하는 열화시험도 많이 적용되고 있다. 열화시험을 비롯한 신뢰성시험들은 대부분 장기간이 소요되고, 시험 종료 후 불합격되면 평가의 반복이 필요하고 이에 따라 평가기간이 길어진다. 그러므로 평가 초기에 이상이 있는 경우에는 미리 불합격 시키는 것이 평가기간을 단축할 수 있다. 조기에 불합격 판정을 하기 위해서는 신뢰성시험 시간과 엄격도의 조정이 필요하다. 본 연구에서는 시험시간 단축을 위한 엄격도 선정방법을 제안하고 광픽업의 적용사례를 제시한다.

• Journal of the Korean Institute of Telematics and Electronics S
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• v.36S no.3
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• pp.18-26
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• 1999

소프트웨어 개발과정에서는 설계 및 코딩에 의해서 프로그램 내에 많은 결함이 삽입되고 시험을 거치는 동안 결함은 발견되고 수정되어 진다. 이와 같은 반복 작업을 통해서 소프트웨어 내에 잠재하고 있는 에러들을 발견, 조치함으로써 소프트웨어 품질은 향상되고 품질에 대한 신뢰성이 높아진다. 본 논문에서는 위와 같은 소프트웨어 개발 과정을 거치는 동안에 많은 시험이 동반되고 이에 따른 시험의 여러 자원이 투입되는데 착안하여 소프트웨어 신뢰도가 성장되어 가는 과정에 수반된 시험능력을 기반으로 한 시험능력의존형 소프트웨어 신뢰도 성장모델을 살펴보고 이를 적용하여 개발중인 소프트웨어에 대한 시험능력 투입에 따른 신뢰도를 평가하였다. 또 S-Shaped Model에 의한 평가치와 비교하여 시험이 진행됨에 따라 소프트웨어 고장 발견율이 상승되는 것을 보였다.

• Proceedings of the Korean Vacuum Society Conference
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• 2014.02a
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• pp.140.2-140.2
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• 2014

인공위성은 우주공간의 고진공 상태와 태양 복사열에 의한 고온 및 극저온이 반복되는 가혹한 환경으로 인해 주요 부품의 기능장애가 초래되므로 발사전 지상에서 열진공 시험장비를 이용한 열진공시험을 수행한다. 위성체의 열진공 시험에 사용되는 열교환기인 베이스플레이트(Baseplate)는 우주 열환경을 모사하기 위하여 직접 방열판 표면에 고온 및 저온의 유체를 공급하여 시험 요구에 따른 필요한 열을 공급하게 된다. 일반적으로 우수한 성능의 위성체 부품의 검증을 위해서 지상의 열환경 시험은 접촉식 히터 및 열교환기를 사용하게 되는데, 이때 적절한 히터 및 블로워 파워를 선정하고 챔버 슈라우드와 열교환에 있어 간섭이 없도록 장비를 운용해야 한다. 본 연구에서는 상용프로그램을 이용하여 열진공 시험용 베이스플레이트에 대하여 전산해석을 수행하였으며, 이를 통해 베이스플레이트 내의 작동 유체의 입구 압력에 의한 열진공 시험용 열교환기의 성능 특성을 관찰하였다.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1994.04a
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• pp.189-189
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• 1994

Q-35의 일회 및 반복투여 연구결과, 자타학 증상은 단지반복투여 피험자에서 중등도의 두통(1예)과 설사(3예)가 관찰되었으나 이들 설사증례는 장내 세균총 검사상 복감염에 의한 것이 아니었다. Q-35 투여 후 Q-EEG 및 평행기능의 장애 등은 관찰되지 않았으며 임상화학 검사상 반복투여 3예에서 SGOT, SGPT의 경미한 상승을 보였으나 이러한 변화는 정상 범위내에서의 변화이었다. Q-35의 반복투여에 따라 투약 3일에서 8일에 걸처 장내세균총은 일부 호기성 및 혐기성 세균총의 감소를 보였으나 투약종료 10일 후에는 투약전 상태로 회복되었다. Q-35는 투여량의 약 70 % 가 24시간 뇨중으로 배설되었으며 일회 및 반복투여의 결과 용량의존적인 동태양상은 관찰할 수 없었다. 50 mg에서 400 mg까지 일회 투여시 5.6-7.1 시간의 혈장반감기를 보였으며, 반복투여 시험에서는 평균 5.6 $\pm$ 0.7 시간의 반감기를 보였다. Q-35는 타액내로 신속히 이행되었으며 타액내 AUC는 혈장 AUC의 약 75 %에 해당하였고, 식사에 의해 약간의 흡수속도지연(Cmax 0.4 시간지연)과 공복시에 비해 82 %의 상대적 생체이용율을 보였다.