• 제목/요약/키워드: Apparent

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전기비저항 수직탐사를 이용한 저수지 그라우팅 구간 평가 (Electrical resistivity survey for evaluation of reinforced region by cement grouting in dike)

  • 송성호;장의웅;김진호;김진성;김진춘
    • 지질공학
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    • 제12권1호
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    • pp.63-73
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    • 2002
  • 누수 보강 저수지의 그라우팅 개선 구간 평가를 목적으로 물-시멘트 배합비별로 제조된 그라우트에 대하여 재령 변화에 따른 전기비저항과 압축강도 변화를 측정하였다. 동일 조건 하에서 그라우트의 농노가 증가할수록 전도도는 높아지고, 대상 매질에 그라우트가 주입되는 경우 주입 이전에 비해 비저항이 상대적으로 낮아지는 효과가 나타나므로 이를 이용한 주입 구간의 판정이 가능함을 확인하였다. 대상 매질이 서로 다른 세 지구에 대한 그라우팅 이후 전기비저항 수직탐사 결과 겉보기 비저항은 수십∼수백 ohm-m 이하로 낮아졌으며, 주입 이후 수 일이 지난 후부터는 점차 증가된 상태로 일정하게 유지되는 것으로 나타나는데, 이는 그라우트가 주입된 이후 대상 지층 내에서 굳어짐에 따른 강도 증가의 결과로 밝혀졌다.

한국인 대학생에게 식이성 단백질의 흡수 및 평형 (Intake/Balance of Dietary Protein in Korean College Student)

  • 이영희;오승호
    • 한국식품영양과학회지
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    • 제23권5호
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    • pp.711-717
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    • 1994
  • This study was conducted to obtain accurate data on intake, apparent digestibility and nitrogen balance of dietary protein which the korean take in habitually. Subjects were 8 male college students, aged from 20 to 26, and maintained their menu and life pattern as usual during a 4-week study. The same amount of diet that the subjects had consumped, and feces and urine were collected and measured to extract their nitrogen content data by Kjeldahl method. From above data, the apparent digestibility and the body nitrogen balance were estimated by determining daily protein intake and excretion. The daily protein intake measured by Jjeldahil method was 88.3$\pm$ 0.9g(1.45/kg of body weight /day) which marked 8.3% higher than that estimatd by food analysis table. The proportional of animal protein against total protein intake was 50.4$\pm$ 2.3%. Daily fecal protein loss was 14.3$\pm$0.6g and the apparent digestibility was 83.8$\pm$ 0.7%. The urinary nitrogen excretion was 10.30$\pm$0.19g. The nitrogen balance considering nitrogen excretion from feces indicated positive balance of 1.06$\pm$0.20g.

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Choice of Thresholding Technique in Micro-CT Images of Trabecular Bone Does Not Influence the Prediction of Bone Volume Fraction and Apparent Modulus

  • Kim, Chi-Hyun;Kim, Byung-Gwan;Guo, X. Edward
    • 대한의용생체공학회:의공학회지
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    • 제28권2호
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    • pp.174-177
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    • 2007
  • Trabecular bone can be accurately represented using image-based finite element modeling and analysis of these bone models is widely used to predict their mechanical properties. However, the choice of thresholding technique, a necessary step in converting grayscale images to finite element models which can thus significantly influence the structure of the resulting finite element model, is often overlooked. Therefore, we investigated the effects of thresholding techniques on micro-computed tomography (micro-CT) based finite element models of trabecular bone. Three types of thresholding techniques were applied to micro-CT images of trabecular bone which resulted in three unique finite element models for each specimen. Bone volume fractions and apparent moduli were predicted for each model and compared to experimental results. Our findings suggest that predictions of apparent properties agree well with experimental measurements regardless of the choice of thresholding technique in micro CT images of trabecular bone.

Nondestructive Estimation of Mechanical Orthogonality of Human Trabecular Bone by Computed Tomography and Spherical Indentation Test

  • Bae Tae Soo;Lee Tae Soo;Choi Kuiwon
    • 대한의용생체공학회:의공학회지
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    • 제26권2호
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    • pp.117-122
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    • 2005
  • The elastic modulus and the apparent density of the trabecular bone were evaluated from spherical indentation tests and Computed Tomography (CT) and their relationship was quantified. The femurs were prepared for trabecular bone analysis. Embedded with respect to their anatomical orientation, the transverse planes of the trabecular bone specimens were scanned at 1㎜ intervals using a CT scanner. The metaphyseal regions of femurs were sectioned with a diamond-blade saw, producing 8㎜ cubes. Using a specially made spherical indentation tester, the cubes were mechanically tested in the anterior-posterior (AP), medial-lateral (ML), and inferior-superior (IS) directions. After determination of modulus from the mechanical testing, the apparent densities of the specimens were measured. The results showed that the IS modulus was significantly greater than both the AP and ML moduli with the AP modulus greater than the ML modulus. This demonstrated that orthogonality was a structural characteristic of the trabecular bone. The power relationship between the modulus and the apparent density was also found to be statistically significant.

단백질원료의 종류에 따른 황복(Takifugu obscurus) 치어의 소화율 및 성장 평가 (Effects of Different Dietary Protein Sources on Apparent Digestibility and Growth in Juvenile River Puffer Takifugu obscurus)

  • 유광열;배승철
    • 한국수산과학회지
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    • 제47권4호
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    • pp.383-389
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    • 2014
  • An 8-week feeding trial was conducted to determine the apparent dry matter and protein digestibility of seven different dietary protein sources by juvenile river puffer Takifugu obscurus. Eight diets containing white fish meal (WFM), brown fish meal (BFM), squid liver powder (SLP), krill meal (KM), leather meal (LM), soybean meal (SM), or fermented soybean meal (FSM) were prepared by mixing a basal diet (BD) with one of the seven test ingredients at a ratio of 7 to 3. Fish averaging $10.8{\pm}0.04g$ were fed the experimental diets in triplicate groups. The apparent dry matter digestibilities of BFM, WFM, FSM, SLP, LM, SM, and KM were 80, 78, 72, 67, 56, 55, and 54%, respectively, while the corresponding apparent protein digestibilities were 96, 96, 93, 92, 89, 88, and 86. The weight gain of fish fed BFM was significantly greater than that of fish fed SM or LM (P<0.05), while it was not significantly different from that of fish fed the BD, WFM, FSM, BFM, SLP, or KM. These results indicated that WFM, BFM, FSM, and SLP are potentially good protein sources for replacing fish meal in river puffer feed.

여대생의 칼슘흡수율에 관한 연구 (Study on the Apparent Absorption Rate of Calcium in College Women)

  • 이현옥
    • Journal of Nutrition and Health
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    • 제13권3호
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    • pp.134-138
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    • 1980
  • The present study was designed to investigate the effects of the level of calcium intake on it's apparent absorption rate in college women. Six college girls aged 19 to 20 were fed general dormitary meals containing approximately500mg of calcium for one week and thereafter, the experimental diets containing about 800mg of calcium were given for one week. Average values for calcium intake, fecal excretion of calcium, and apparent absorption rateof calcium in both periods were determined and these values for two periods were compared by using t-test. 1) Average intakes of calcium, protein, and fat of the subjects during the period of experimental diet were significantly higher than those of general diet period. 2) Higher consumption of three food groups; meat, poultry, and fishes, fruits and vegetables, and fats and oils were noted during experimental period. However, there was no significant difference in the consumption of cereals and milk groups during these two periods. 3) The apparent absorption rate of calcium during the experimental period was higher (64%) than the one for general diet period (56%). It was noteworthy that average calcium intakes was higher during the experimental diet period (785mg) than 536mg for general diet period while the fecal excretions of calcium in both periods were not significantly different.

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역해석기법을 통한 NATM 터널의 안정성 평가 (Stability Estimation of NATM Tunnel due to Excavation using Back Analysis)

  • 이재호;김영수;김광일;박진규;박시현;최칠용
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2008년도 춘계 학술발표회 초청강연 및 논문집
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    • pp.494-504
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    • 2008
  • Successful design, construction and maintenance of NATM tunnel demands prediction, control, stability estimation and monitoring of surface settlement, gradient and ground displacement with high accuracy. Back analysis using measured data and forward analysis have been and are indispensable tools to achieve this goal. Sakurai provided the hazard warning levels for assessing the stability of tunnels using the relation of critical strain and apparent Young's modulus. This paper performed the estimation of tunnel stability on construction. Firstly, the apparent Young's modulus concept and back analysis method is introduced for the assessment of tunnel safety during excavation a brief framework. Secondly, this paper deals with case study using "Apparent Young's modulus" and "Back analysis" for the purpose of estimating the stability of NATM tunnel in Korea. Finally, a general method that can be estimated the tunnel stability discussed by a flow chart.

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The Effect of Dietary Phytate Content on Iron Absorption and Status in Young Korean Women

  • Kim, Ji-Hye;Li, Sun-Hee;Joung, Hyo-Jee;Paik, Hee-Young
    • International Journal of Human Ecology
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    • 제4권1호
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    • pp.35-44
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    • 2003
  • This study investigated the effects of dietary phyate reduction on the apparent absorption and biochemical parameters of iron status in young Korean women. Fourteen healthy, young women consumed low and high phytate diets for ten days of each experimental period. Duplicate diet samples, a fasting blood sample on day 9, and complete fecal samples for five consecutive days starting from day 5 of each diet period were collected. The iron content of diet and fecal samples were analyzed to calculate apparent absorption. Serum samples were analyzed for iron, ferritin, transferrin receptor and TIBC; transferrin saturation was also calculated. The apparent absorption of iron tended to increase in the low phytate period (32.51%) compared to the high phytate period (17.91%), but the difference was not significant (p=0.06). Serum ferritin decreased and serum transferrin receptor increased significantly during the low phytate diet although the mean values were within the normal range. Serum iron and transferrin saturation did not change significantly. In conclusion, the results indicated that reducing dietary phytate for ten days negatively affected iron nutritional parameters, but it moderately and positively affected apparent iron absorption in young Korean women. Further research on the long-term effects of a low phytate diet with an adequate iron content for vows Korean women is necessary.

Laser Scanning을 이용한 극세선 집속체의 겉보기 굵기 측정과 불균제 특성 (Measuring and Characterizing the Apparent Thickness and its Irregularity of Fine Wire Bundle by Using a Laser Scanning Method)

  • 허유;김종성;백영남
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 2003년도 춘계학술대회 논문집
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    • pp.1573-1576
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    • 2003
  • The quality of bundles is closely related with the apparent thickness. Especially the variation of apparent thickness of bundle determines the qualify of the plane structure made or the bundle such as surface evenness, pore size, and the shape of air-gap, etc.,. This study is dealing with the development of a new measuring system of the thickness of bundle or cross-section by determining the size of the shadow of the object covered by a laser slit beam. Also the measured signal is characterized in terms of the correlogram, the irregularity in wavelength. The correlogram for the irregularity of several sample types could be represented by a sinusoidal function with exponentially decaying amplitude. Moreover, influence of the measuring speed on the signal and the characteristic differences according to the different types of bundle are investigated.

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Comparative study on the behavior of soil fills on rigid acrylic and flexible geotextile containers

  • Kim, Hyeong-Joo;Won, Myoung-Soo;Lee, Jang-Baek;Joo, Jong-Hoon;Jamin, Jay C.
    • Geomechanics and Engineering
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    • 제9권2호
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    • pp.243-259
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    • 2015
  • Comparative study has been performed to investigate the behavior of dredged fills on rigid (Model 1) and flexible (Model 2) containers. The study was focused on the sedimentation of soil fills and the development of total stresses. Model 1 is made of an acrylic cylinder and Model two is a scale-size geotextile tube. Results indicate that for rigid containers, significant decrease of the sediment height is apparent during the dewatering process. On the other hand, because the geotextile is permeable, the water is gradually dissipated during the filling process on flexible containers. Hence, significant loss in the tube height is not apparent during the duration of the test. Pressure spikes are apparent on rigid containers during the filling process which can be attributed to the confining effect due to hydrostatic pressure. For the flexible containers, the pressure readings gradually increases with time during the filling process and normalize at the end on the filling stage. No pressure spikes were apparent due to the gradual dissipation of pore water pressure.