• Asian-Australasian Journal of Animal Sciences
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• 제22권9호
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• pp.1256-1266
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• 2009

Effects of particle size and physical effective fibre (peNDF) of rice straw in diets on chewing activities, feed intake, flow, site and extent of digestion and rumen fermentation in goats were investigated. A 4${\times}$4 Latin square design was employed using 4 mature Liuyang black goats fitted with permanent ruminal, duodenal, and terminal ileal fistulae. During each of the 4 periods, goats were offered 1 of 4 diets that were similar in nutritional content but varied in particle sizes and peNDF through alteration of the theoretical cut length of rice straw (10, 20, 40, and 80 mm, respectively). Dietary peNDF contents were determined using a sieve for particle separation above 8 mm, and were 17.4, 20.9, 22.5 and 25.4%, respectively. Results showed that increasing the particle size and peNDF significantly (p<0.05) increased the time spent on rumination and chewing activities, duodenal starch digestibility and ruminal pH, and decreased ruminal starch digestibility and $NH_{3}$-N concentration. Intake and total tract digestibility of nutrients (i.e. dry matter, organic matter, and starch) and ruminal fermentation were not affected by the dietary particle size and peNDF. Increased particle size and peNDF did not affect ruminal fibre digestibility, but had a great impact on the intestinal and total tract fibre digestibility. The study suggested that rice straw particle size or dietary peNDF was the important influential factor for chewing activity, intestinal fibre and starch digestibility, and ruminal pH, but had minimal impact on feed intake, duodenal and ileal flow, ruminal and total tract digestibility, and ruminal fermentation.

• Asian-Australasian Journal of Animal Sciences
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• 제23권8호
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• pp.1022-1027
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• 2010

Effects of increasing dietary rice straw on chewing activity, ruminal fermentation, and fibrolytic enzyme activity in growing goats were investigated in a $4{\times}4$ Latin Square experiment. The goats were offered four diets with an increasing proportion of rice straw (i.e. 0.05, 0.10, 0.15 and 0.20, respectively, on dry matter basis). Increasing level of rice straw increased ($P_{linear\;effect}$ <0.05) the time spent on eating, ruminating, and chewing. The ruminal pH and acetate: propionate ratio were increased ($P_{linear\;effect}$ <0.05), while the $NH_3$-N concentration was decreased ($P_{linear\;effect}$ <0.01). Increasing level of rice straw in the diet increased ($P_{linear\;effect}{\leq}0.01$) molar proportion of acetate and isovalerate, and decreased ($P_{linear\;effect}$ <0.01) molar proportion of propionate. The CMCase, xylanase and cellobiase activities in the rumen were decreased ($P_{linear\;effect}$ <0.05) with increasing level of dietary rice straw, whereas the avicelase activity was increased ($P_{linear\;effect}$ <0.01). In summary, increased level of rice straw elevated the dietary neutral detergent fibre (NDF) content in the diet and had a great impact on chewing activity and ruminal fermentation.

• Geomechanics and Engineering
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• 제16권4호
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• pp.415-421
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• 2018

A location determining method is proposed for critical sliding surface in the stability analysis of the filling materials in karst caves. First, a preliminary location of the sliding surface is determined based on simulation results which includes displacement contour and plastic zone. The sliding surface will locate on the bottom contact interface when the friction angle is relative small. However, a weakened contact interface always becomes the critical sliding surface no matter what the friction angle is. Then when the friction angle becomes larger, the critical sliding surface inside fillings can be determined by a parabola, the coefficient of which increases linearly with the friction angle under the same cohesion. Finally, the critical sliding surface approximately remains unchanged with friction angle. The influence of cohesion is similar to that of friction angle. Although affected by shape, size or position of the karst cave, the critical sliding surface mainly depends on both friction angle and cohesion. Thus, this method is always useful in determining the critical sliding surface.

• Geomechanics and Engineering
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• 제8권5호
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• pp.631-647
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• 2015

Engineers may encounter unpredictable cavities, sinkholes and karst conduits while tunneling in karst area, and water inrush disaster frequently occurs and endanger the construction safety, resulting in huge casualties and economic loss. Therefore, an optimal classification method based on grey system theory (GST) is established and applied to accurately predict the occurrence probability of water inrush. Considering the weights of evaluation indices, an improved formula is applied to calculate the grey relational grade. Two evaluation indices systems are proposed for risk assessment of water inrush in design stage and construction stage, respectively, and the evaluation indices are quantitatively graded according to four risk grades. To verify the accuracy and feasibility of optimal classification method, comparisons of the evaluation results derived from the aforementioned method and attribute synthetic evaluation system are made. Furthermore, evaluation of engineering practice is carried through with the Xiakou Tunnel as a case study, and the evaluation result is generally in good agreement with the field-observed result. This risk assessment methodology provides a powerful tool with which engineers can systematically evaluate the risk of water inrush in karst tunnels.

• 동굴
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• 제95호
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• pp.23-33
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• 2009

본 연구는 중국의 동굴 자원과 동굴에 관한 연구에 대해 요약해 보았다. 그 결과는 다음과 같다. 첫째, 중국의 석회암동굴은 주로 카르스트지형이 집중된 열대와 아열대를 아우르는 서남지역에 집중되었다. 최근에는 북부 지역에서도 상당한 규모의 석회암동굴이 발견되고 있다. 둘째, 중국은 화산지형이 넓게 분되었지만 대부분 사화산으로서 용암동굴이 상대적으로 적다. 주로 해남도(海南島)에 분포되어 있다. 셋째, 중국에서는 최근에 와서 주로 동굴의 발육과 진화, 동굴 석순의 고환경기록, 동굴생물, 관광개발, 동굴환경 등에 대한 다양한 연구가 활발하다.

• 대한지리학회지
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• 제49권5호
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• pp.639-655
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• 2014

우발라는 규모, 형성원인, 발달과정, 기하학적 구조, 수문학적 특징, 돌리네와의 관계에서 다른 카르스트 와지와 구분되는 특징을 갖는다. 광덕리 카르스트 와지의 지질, 고도, 곡중분수계, 하천쟁탈의 증거를 분석한 결과는 우발라의 성인적, 과정적, 구조적, 수문학적 특성에 잘 부합한다. 우발라의 지형, 수문적 특성은 와지내부의 가뭄이나 용수부족 문제를 일으키는데, 우발라 내부의 주민들은 지형적 환경적 제약을 극복하기 위한 적극적 대응방식을 보였다. 집중호우에 따른 침수와 산사태를 예방하기 위해 지형을 이용한 배수시설을 설치하고, 우발라 내 외곽에 존재하는 지하수와 용천수에는 우물, 펌프, 관정, 간이상수도와 같은 시설을 설치하여 용수를 취득함으로써 경관을 변화시켰다. 우발라와 같은 카르스트 와지에서의 입지와 토지이용은 지형과 수문특성이라는 환경적 조건과 관련된 것으로 단순히 공간적 규모에 의해 입지가 결정된다는 기존의 관점에 수정이 요구된다.

• 동굴
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• 제90호
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• pp.35-56
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• 2009

본 연구의 목적은 동굴환경의 황폐화에 대한 지속가능한 동굴의 연구, 관광 및 보존을 위하여 첨단정보화 기술인 유비쿼터스 정보기술을 활용한 새로운 차원의 동굴시스템을 제시하는데 있다. 이러한 환경문제를 극복할 수 있는 방안으로 첫째, 동굴에 대한 법제도나 조례 등으로 강력한 관리방안이 제시되거나 휴식년제 도입 등으로 행정적인 방안이 있으며, 둘째, 최첨단 정보기술을 적용하여 효율적이고 지속가능한 동굴의 관리로 지하동굴 자원의 청정환경을 도모하는 방법이 있다. 유비쿼터스 동굴의 구축에는 첨단 자동정보시스템 인 감지시스템(USN), 모니터링시스템(RFID/UFID), 무선통신시스템(WiBro/WiFi), 공간정보시스템(GIS), 항공레이저시스템(LiDAR), 저열 조명시스템(ELD) 및 통합관리시스템 등이 적용되었다. 이러한 유비쿼터스 동굴 구현에 필요한 첨단화 정보기술분야의 산업적인 융합에 의한 차세대 동굴살리기 명품솔류션 구현을 통하여 공간정보기반의 유비쿼터스 동굴관리시스템의 모델을 제시하였다. 따라서 u-cave모델은 정책의 적용에 따라 동굴의 자연관리, 생태관리, 시설관리, 관광관리, 문화관리 및 소득창출 등의 시너지 효과를 달성할 수 있는 것으로서 동굴의 자연환경보존 기반의 수단으로서 기여 될 수 있다.

• 한국가정과학회지
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• 제7권3호
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• pp.49-58
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• 2004

The purpose of the study was to verify if or not as funtional food by estimating antitumor activity and antimicrobial activity of Coriolus versicolor(Fr.)Quel and Ganoderma Lucidum (Fr.)Karst. 1. The contents of moisture. crude fiber and crude protein of GL were higher $(18.28\%,\;10.3\%,\;78.4\%)$ than that of CV, but the content of crude lipid GL was higher than that of CV. 2. Inhibitory effects of on the growth of AGS human gastric adenocarcinoma cells and HT-29 human colon adenocarcinoma cell were increased by increasing of concentration in added methanol extracts of CV and GL. 3. Antimicrobial activity on Escherichia col1; Staphylococcus aureus, Salmonella typhimurium existed methanol extracts of CV. Therefore. it is suggested that CV is worth as functional food.

• 한국가정과학회지
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• 제7권2호
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• pp.31-46
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• 2004

The purpose of this study was to investigate the physiological functionality of Coriolus versicolor Quel (CV) and Ganoderma IUCIdum (Fr.)Karst (GL) by estimate the proximate composition and content of antioxidant components. 1. In the physicochemical property. the content of proximate composition of GL was higher 08.28% of moisture, 10.3% of crude protein, 78.4% of crude fiber) than that of CV, but the content of crude lipid and ashes of GL was higher than that of CV. 2. CV had relatively higher content of antioxidant components such as total phenol, carotenoids and v itamin C. than GL did. Antioxidant mineral components such as magnesium and zinc also had relatively higher in CV than in GL. 3. TBA value, conjugated diene production, LDL oxidation, DPPH of methanol extracts in CV and GL were as high as a-Tocopherol.

• Geomechanics and Engineering
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• 제18권1호
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• pp.1-9
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• 2019

In this study, both 2D and 3D failure shapes of rock mass above the water-filled cavity are put forward when the surrounding rock mass cannot bear the pressure caused by the water-filled cavity. Based on the analytical expressions derived by kinematic approach, the profiles of active and passive failure patterns are plotted. The sensitivity analysis is conducted to explore the influences of different rock parameters on the failure profiles. During the excavation of the deep tunnels above the karst cavity, the water table always changes because of progressive failure of cavity roof. Therefore, it is meaningful to discuss the effects of varying water level on the failure patterns of horizontal rock layers. The changing laws of the scope of the failure pattern obtained in this work show good consistency with the fact, which could be used to provide a guide in engineering.