• 제목/요약/키워드: initial slope

검색결과 350건 처리시간 0.025초

Effects of green tea or $Sasa$ $quelpaertensis$ bamboo leaves on plasma and liver lipids, erythrocyte Na efflux, and platelet aggregation in ovariectomized rats

  • Ryou, Sung-Hee;Kang, Min-Sook;Kim, Kyu-Il;Kang, Young-Hee;Kang, Jung-Sook
    • Nutrition Research and Practice
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    • 제6권2호
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    • pp.106-112
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    • 2012
  • This study was conducted to investigate the effects of $Sasa$ $quelpaertensis$ bamboo and green tea on plasma and liver lipids, platelet aggregation, and erythrocyte membrane Na channels in ovariectomized (OVX) rats. Thirty female rats were OVX, and ten female rats were sham-operated at the age of 6 weeks. The rats were divided into four groups at the age of 10 weeks and fed the experiment diets: sham-control, OVX-control, OVX-bamboo leaves (10%), or OVX-green tea leaves (10%) for four weeks. Final body weight increased significantly in the OVX groups compared with that in the sham-control, whereas body weight in the OVX-green tea group decreased significantly compared with that in the OVX-control ($P$ < 0.01). High density lipoprotein (HDL)-cholesterol level decreased in all OVX groups compared with that in the sham-control rats ($P$ < 0.05) but without a difference in plasma total cholesterol. Plasma triglycerides in the OVX-green tea group were significantly lower than those in the sham-control or OVX-control group ($P$ < 0.05). Liver triglycerides increased significantly in the OVX-control compared with those in the sham-control ($P$ < 0.01) but decreased significantly in the OVX-green tea group compared with those in the OVX-control or OVX-bamboo group ($P$ < 0.01). Platelet aggregation in both maximum and initial slope tended to be lower in all OVX rats compared with that in the sham-control rats but was not significantly different. Na-K ATPase tended to increase and Na-K cotransport tended to decrease following ovariectomy. Na-K ATPase decreased significantly in the OVX-green tea group compared with that in the OVX-control group ($P$ < 0.01), and Na-K cotransport increased significantly in the OVX-bamboo and OVX-green tea groups compared with that in the OVX-control ($P$ < 0.05). Femoral bone mineral density tended to be lower in OVX rats than that in the sham-control, whereas the green tea and bamboo leaves groups recovered bone density to some extent. The results show that ovariectomy caused an increase in body weight and liver triglycerides, and that green tea was effective for lowering body weight and triglycerides in OVX rats. Ovariectomy induced an increase in Na efflux via Na-K ATPase and a decrease in Na efflux via Na-K cotransport. Furthermore, consumption of green tea and bamboo leaves affected Na efflux channels, controlling electrolyte and body water balance.

마그네시아-인산칼륨 시멘트에 대한 인산염 비 및 물-결합재비의 영향 (Effect of Phosphate-to-binder and Water-to-binder Ratio on Magnesia-potassium Phosphate Cement)

  • 이경호;윤현섭;양근혁
    • 콘크리트학회논문집
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    • 제29권3호
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    • pp.275-281
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    • 2017
  • 본 연구는 물-결합재비(water-to-binder ratio, W/B) 및 인산염-결합재비(phosphate-to-binder ratio, P/B)가 마그네시아-인산칼륨 시멘트(magnesium-potassium phosphate cement, MKPC) 모르타르의 플로, 응결시간, 압축강도발현 및 pH 변화에 미치는 영향성에 대한 평가이다. MKPC 모르타르의 P/B가 0.3 및 0.5일 때 W/B 범위 20~40%에 대하여 10 배합의 모르타르 실험을 실시하였으며, X-선 회절 분석(X-ray diffraction, XRD), 전자현미경(scanning electron microscope, SEM) 및 수은압입법(mercury intrusion porosimetry, MIP) 분석을 위해 MKPC의 반응생성물 및 미세공극분포를 평가하였다. 실험결과, MKPC 모르타르의 플로 및 응결시간은 P/B의 증가에 따라 감소하였으며, P/B가 0.3에서 0.5로 증가함에 따라 종결시간은 약 24% 감소하였다. MKPC 모르타르의 초기 압축강도 발현 기울기의 경우 콘크리트 구조기준에서 제시하는 시멘트 콘크리트 대비 높은 수준에 있었다. 재령 28일의 압축강도 30 MPa 이상 및 pH 9.0 이하를 만족하기 위해 MKPC 모르타르의 P/B 및 W/B는 각각 0.5이상 및 30% 이하가 추천된다. MKPC의 반응생성물인 스트루바이트(struvite)-K의 결정은 MKPC의 P/B 및 W/B가 높을수록 증가하였는데, 이로 인해 거대 모세관 공극은 감소하였다.

풍화암소켓 대구경 현장타설말뚝의 선단보강그라우팅 사례 (A Case Study of Post-Grouted Drilled Shaft in Weathered Rock)

  • 권오성;정성민;최용규
    • 한국지반공학회논문집
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    • 제27권6호
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    • pp.5-16
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    • 2011
  • 현장타설말뚝의 포스트그라우팅 기법은 말뚝 시공시 발생하는 슬라임과 굴착으로 인해 교란된 원지반을 압축 및 보강함으로써 기초의 선단지지력을 현저히 증강시키는 것으로 알려져 있다. 그러나 현재까지 국내외적으로 통용되는 설계지침 또는 시방은 없는 상태이며, 특히 국내에서는 말뚝 포스트그라우팅 기법이 설계지지력 증강 목적이 아닌, 소요지지력에 미달되는 말뚝에 대한 보수보강의 개념으로 이해되고 있어, 그 효과에 비해 관련 연구 및 실용화 실적이 미비한 실정이다. 본 연구에서는 포스트그라우팅 기법의 국내 풍화대소켓 현장타설말뚝에의 적용성을 검증하기 위해 풍화암 근입 대구경 현장타설 콘크리트말뚝 시공 현장을 선정하여 포스트그라우트 시험시공을 실시하였다. 또한 포스트그라우팅 말뚝, 그리고 인접한 미보강 말뚝에 대한 정재하시험을 수행함으로써, 포스트그라우팅이 현장타설말뚝의 축방향 지지력 증강에 미치는 효과를 정량적으로 비교분석해 보고자 하였다. 정재하시험 결과, 선단보강 말뚝 선단하중-침하곡선의 초기기울기가 미보강 말뚝 선단히중-침하곡선의 기울기에 비해 4배 이상 증가였으며, 허용침하량(1%D) 기준으로 보강 및 미보강 말뚝의 선단지지력은 각각 12.0MPa, 7.0MPa로 나타나, 포스트그라우팅 적용 후 말뚝의 허용선단지지력이 70% 이상 증가하는 것을 확인하였다.

The Optimum Methionine to Methionine Plus Cystine Ratio for Growing Pigs Determined Using Plasma Urea Nitrogen and Nitrogen Balance

  • Qiao, Shiyan;Piao, Xiangshu;Feng, Zhanyu;Ding, Yuhua;Yue, Longyao;Thacker, P.A.
    • Asian-Australasian Journal of Animal Sciences
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    • 제21권3호
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    • pp.434-442
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    • 2008
  • The objective of this study was to determine the optimum ratio of methionine to methionine plus cystine for growing pigs. A nitrogen balance trial was conducted using a total of 21 barrows (Large WhiteLandrace) over two replicates. The initial body weight was $20.36{\pm}1.22kg$ (mean${\pm}$SD) in the first replicate and $23.54{\pm}1.02kg$ (mean${\pm}$SD) in the second. For each replicate, the 21 pigs were randomly assigned to one of seven dietary treatments with three observations per treatment. The diets included a methionine and cystine-deficient basal diet with all other essential nutrients meeting nutrient requirements and six diets formulated with graded levels of DL-methionine (0.00, 0.03, 0.06, 0.10, 0.13, 0.16%) and $L-Cystine{\cdot}HCl{\cdot}H_2O$ (0.19, 0.15, 0.11, 0.07, 0.04, 0.00%). This resulted in ratios of methionine to methionine plus cystine of 41.3, 29.6, 35.3, 41.2, 46.0, 51.6 and 57.5%. Each experimental period lasted 12 days consisting of a seven-day adaptation period followed by a five-day total collection of urine and feces. During the collection period, pigs were fed 900 g/day for the first replicate and 1,200 g/day for the second replicate. The feed was provided in three equal portions at 0800, 1500, and 2200 h daily. Pigs had ad libitum access to water after feeding. There was a linear (p<0.01) and quadratic (p<0.01) effect on daily gain and feed conversion as the ratio of methionine to methionine plus cystine increased. Pigs receiving the diets providing a methionine to methionine plus cystine ratio of 51.6% had the best daily gain and feed conversion. Plasma urea nitrogen was also lowest for this treatment. Nitrogen retention increased (p<0.01) as the relative proportion of methionine increased up to 51.6% and then a downward trend occurred at 57.5%. The quadratic regression model, as well as one- and two- slope regression line models, were used to determine the optimum ratio of methionine to methionine plus cystine. Eliminating the 35.3% methionine to methionine plus cystine treatment resulted in $R^2$ values in excess of 0.92. The optimal ratio of methionine to methionine plus cystine was estimated to be 54.15% for nitrogen retention and 56.72% for plasma urea nitrogen.

Developing the Accurate Method of Test Data Assessment with Changing Reliability Growth Rate and the Effect Evaluation for Complex and Repairable Products

  • So, Young-Kug;Ryu, Byeong-Jin
    • 한국신뢰성학회지:신뢰성응용연구
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    • 제15권2호
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    • pp.90-100
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    • 2015
  • Reliability growth rate (or reliability growth curve slope) have the two cases of trend as a constant or changing one during the reliability growth testing. The changing case is very common situation. The reasons of reliability growth rate changing are that the failures to follow the NHPP (None-Homogeneous Poisson Process), and the solutions implemented during test to break out other problems or not to take out all of the root cause permanently. If the changing were big, the "Goodness of Fit (GOF)" of reliability growth curve to test data would be very low and then reduce the accuracy of assessing result with test data. In this research, we are using Duane model and AMSAA model for assessing test data and projecting the reliability level of complex and repairable system as like construction equipment and vehicle. In case of no changing in reliability growth rate, it is reasonable for reliability engineer to implement the original Duane model (1964) and Crow-AMSAA model (1975) for the assessment and projection activity. However, in case of reliability growth rate changing, it is necessary to find the method to increase the "GOF" of reliability growth curves to test data. To increase GOF of reliability growth curves, it is necessary to find the proper parameter calculation method of interesting reliability growth models that are applicable to the situation of reliability growth rate changing. Since the Duane and AMSAA models have a characteristic to get more strong influence from the initial test (or failure) data than the latest one, the both models have a limitation to contain the latest test data information that is more important and better to assess test data in view of accuracy, especially when the reliability growth rate changing. The main objective of this research is to find the parameter calculation method to reflect the latest test data in the case of reliability growth rate changing. According to my experience in vehicle and construction equipment developments over 18 years, over the 90% in the total development cases are with such changing during the developing test. The objective of this research was to develop the newly assessing method and the process for GOF level increasing in case of reliability growth rate changing that would contribute to achieve more accurate assessing and projecting result. We also developed the new evaluation method for GOF that are applicable to the both models as Duane and AMSAA, so it is possible to compare it between models and check the effectiveness of new parameter calculation methods in any interesting situation. These research results can reduce the decision error for development process and business control with the accurately assessing and projecting result.

Methodologies for the Determination of Endogenous Phosphorus Losses in Growing Pigs

  • Alves, Debora Aline;da Rocha, Leonardo Tombesi;dos Santos Camargo, Claudiele Aparecida;Figueiredo, Andriele Medianeira;Ceron, Marcos Speroni;Lucca, Walter;Zanella, Irineo;de Oliveira, Vladimir
    • Asian-Australasian Journal of Animal Sciences
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    • 제29권11호
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    • pp.1632-1638
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    • 2016
  • A study was conducted to compare the endogenous basal losses of phosphorus (EBLP) in pigs fed diets containing gelatin (GEL) or spray-dried porcine plasma (SDPP) as protein sources and to determine the standardized total tract digestibility (STTD) of phosphorus (P) in SDPP. The trial was carried out at the Federal University of Santa Maria, Brazil. Twelve castrated pigs with an initial body weight of 55 kg were individually allotted in metabolic crates during two 12-day periods, each with 7 days of adaptation and 5 days of total fecal collection. The beginning and the end of the collecting periods were determined according to the marker-to-marker approach, using ferric oxide as an indigestible marker. Pigs were submitted to four semi-purified diets, one being a P-free diet with 30% of GEL as the protein source and three were diets with 10%, 20%, and 30% inclusion of SDPP respectively. Data were subjected to analysis of variance and the model included the effects of period, animal and treatments; the results of the three diets with increased levels of SDPP were subjected to linear regression analysis. The intercept of the relation of between ingested P and absorbed P represented the EBLP, while the slope indicated the STTD of P in SDPP. The EBLP means obtained by P-free diet and regression method were compared with the Student t test. The EBLP were 128.95 mg/kg dry matter intake (DMI) and 153.63 mg/kg DMI (standard error = 77.0; p<0.06) using the P-free diet with GEL as the protein source and the regression method, obtained with diets containing increased levels of SDPP, respectively. The apparent digestibility of P was 87.9%, 94.2%, and 92.9% for the treatments containing 10%, 20%, and 30% inclusion of SDPP, respectively. The estimated STTD of P obtained with the linear regression was 97.4%. When the EBLP estimated by the P-free diet was used to corrected the apparent digestibility of P in diets containing SDPP, the STTD of P in SDPP was 96.9%, 98.8%, and 95.9% for 10%, 20%, and 30% SDPP, respectively. Therefore, it can be concluded that SDPP can replace GEL to estimate the endogenous losses of P. In addition, the STTD of P in SDPP estimated with the P-free diet was 97.2% and it was 97.4% by the regression method, utilizing SDPP.

브라질 Mato Grosso do Sul 주에서의 유칼리나무 식재계획(植栽計劃)을 위한 농장토지이용구분(農場土地利用區分)에 관한 연구(硏究) - 원격탐사기술(遠隔探査技術)과 지리정보(地理情報)시스템(GIS)의 적용(適用) - (Farm Land Use Classification for the Planning of Planting of Eucalyptus Spp. at Mato Grosso do Sul of Brazil Using Remote Sensing and Geographic Information System)

  • 우종춘
    • 한국산림과학회지
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    • 제88권2호
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    • pp.157-168
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    • 1999
  • 본 연구는 브라질의 서부에 있는 Mato Grosso do Sul 주의 Jangada 농장과 Jamaica 농장에 유칼리나무 식재계획(植栽計劃)을 원활히 추진하기 위해 인공위성사진을 이용하여 식생분류(植生分類) 및 토지이용구분(土地利用區分), 경사도(傾斜度) 및 영구자연보존지역(永久自然保存地域) 등을 분석한 결과이다. Mato Grosso do Sul 주의 서쪽에 위치하는 이 지역은 볼리비아와 파라과이의 국경근처에 있기 때문에 지정학적(地政學的)으로 매우 중요하다. 또한 물품수출이 파라과이강을 통해서 아르헨티나의 수도인 부에노스아이레스 까지 도달될 수 있고 브라질의 남동지역과 안데스산맥에 연한 국가들을 연결하는 국도(國道)와 철도(鐵道)가 존재한다. 농장의 산림(山林) 피복지역(被服地域)의 일차해석을 위한 기초로서 Radambrasil프로젝트 SF-21 Campo Grande로부터 얻은 식생지도가 사용되었고, 그 이후에 현장조사(現場調査)가 수행되었다. 최초의 이미지해석이 이루어진 후에 사용급과 토지점유에 대한 개념정의가 이루어 졌으며 스펙트럼분류가 행해졌다. Jangada 농장과 Jamaica 농장에 있어서 산림지역 Savanna와 초원지역 Savanna가 전체 총면적의 68% 정도를 차지하고 있다. 현재로서 만족한 연구결과에도 불구하고 이미 이루어진 평가결과(評價結果)에 기초하여 프로젝트 발전을 위한 수정(修正)과 보완(補完)이 요구된다. 특히 토양(土壤)과 지형(地形)을 포함해서 환경인가에 대한 상세한 분석이 병행되어야 할 것이다.

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댐 비상방류 설계기준 선정을 위한 수리수문학적 검토(I) (Hydraulic & Hydrologic Design Criteria for an Emergency Discharge of Reservoir (I))

  • 손광익;이재응
    • 한국수자원학회논문집
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    • 제48권3호
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    • pp.149-158
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    • 2015
  • 비상방류시설은 안전한 댐 운영 및 유지관리를 위해서 절대적으로 필요한 시설임에도 불구하고 국내 댐의 경우 이를 고려한 설계가 이루어지지 않아 각 댐의 비상방류 대응 적정성을 판단하기 곤란한 상황이다. 특히 국내 댐의 경우 비상방류시설규모를 산정하는 기준이 일정치 않을 뿐만 아니라 대부분의 용수댐은 별도의 방류시설 조차도 없는 실정이다. 따라서 본 연구에서는 기존댐 방류시설 현황 분석, 국내외 비상방류시설 설계기준 등의 검토와 함께 국내 댐설계기준을 적용한 가상 댐체와 수어댐을 대상으로 수위에 따른 방류능 분석을 수행하였다. 또한 SEEP 프로그램 등을 활용, 수위저하 속도에 따른 제체의 사면 안정성을 검토함으로써 비상방류 시설의 적정규모 산정기준을 제시하고자 하였다. 이를 위하여 수리학적 해석을 통해 저류수심에 따른 제체에 작용하는 힘을 분석하였으며 수위저하 속도 변화에 따른 제체의 안정성을 검토하여 허용수위저하 속도 범위를 제시하였다. 수위 25% 저감은 하중을 50%까지 감소시켜 초기수위 저감이 중요한 것을 알 수 있었다. 가상 댐체는 물론 수어댐에 수위저하 속도 1 m/일을 적용하더라도 제체의 안전성은 보장됨을 확인하였다. 다만, 방류능과 방류 소요일수는 수위별 저류용량 등 저류지 특성과 밀접한 관계가 있어 초기대응을 위해서는 7~10일 이내에 저류수심의 25%를 먼저 방류시키고 나머지 방류량은 1~2개월 이내에 방류할 것을 제안하였다.

수정 SBEACH 모델에 의한 호안 전면의 침퇴적 예측 (Modified SBEACH Model for Predicting Erosion and Accretion in front of Seadike)

  • 한재명;김규한;신성원
    • 한국해안·해양공학회논문집
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    • 제23권6호
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    • pp.482-488
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    • 2011
  • 호안은 파랑의 직접적인 영향을 차단하여 배후지역의 이용성을 극대화하기 위해 전빈의 배후면에 건설되는 해안시설물로서 대상지역의 설계파와 조석 조건 하에서 월파가 심각하지 않은 해안에 건설된다. 따라서, 호안의 위치는 주변 환경을 고려하여 가능한 한 높은 위치로 결정하는 것이 일반적이며, 호안의 천단고는 단위시간당 월파량을 허용 가능한 범위 이내로 제어할 수 있도록 계획한다. 그러나 호안 전면의 백사장은 입사 파랑에 의해 계속 변형되고 결국에는 원래 설계 초기의 경사를 유지할 수 없게 되는 경우가 많다. 이러한 호안 전면 지형의 침식과 퇴적에 의해 원래 설계시 고려되었던 천단고와 월파량은 변하게 되며 호안의 설치 깊이가 감소하여 호안의 안정성을 위협하게 된다. 본 연구에서는 2차원 수리모형 실험과 수정 SBEACH모형을 이용한 수치모델링을 통하여, 처오름 지역에 있어서의 호안 전면부의 국부적인 세굴과 호안의 설치깊이의 관계를 검토하였다. 본 연구를 통하여, 수정한 SBEACH에 호안의 위치에 대한 경계조건을 적절히 적용함으로써, 침식형 파랑 입사시 호안 기초에서의 국부세굴 산정이 가능함을 확인 할 수 있었다.

화성호 유입하천의 강우시 비점오염물질 유출특성 (The characteristics of discharged non-point pollutants on Hwa-sung lake inflow streams on precipitation)

  • 이상은;최이송;이인호;홍대벽;오종민
    • 환경영향평가
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    • 제20권5호
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    • pp.651-661
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    • 2011
  • The purpose of this study is to estimate the characteristics and pollutant loadings of non-point pollutants that flowed in the streams on precipitation for pollutant loading reduction of Hwa-sung lake inflow streams. Although it has been made an effort to improve the water quality of Hwa-sung basin through the strategies for the preservation of water quality, it is shown that the water quality is not greatly improved. Because it has been industrialized and urbanized near Hwa-sung basin so that it is difficult to reduce the water pollution due to the increase in pollutant loadings of point and non-point sources. In this study, it is investigated the outflow characteristics of non-point pollutants that discharged with storm runoff and estimated the effect of runoff on Hwa-sung basin. The final goal of this study is to utilize the basic information for proper management and strategies of non-point sources on Hwa-sung basin. At the result of inflow streams, Ja-an stream that has the greatest pollutant loadings on precipitation is strongly influenced on the water quantity of Hwa-sung basin. On the other hand, it is shown that Nam-yang stream is strongly influenced on the SS concentration of Hwasung basin among them. Also, all streams; Nam-yang, Ja-ahn, Ah-eun stream; has the degree of slope more than or near 1 in the correlation results so that they have strong pollutant loading impact and the concentration of SS is the highest among other pollutants. So, specific studies on initial rain phenomena are more necessary to manage the pollutants economically. Also, the proper control of SS concentration is required to manage the effluent pollutants effectively on precipitation. So, it is necessary to consider the strategies for non-point pollutants as well as point pollutants when the new management is imposed to reduce the pollutant load for improvement of Hwa-sung basin.