• Korean Journal of Poultry Science
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• v.12 no.2
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• pp.97-105
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• 1985

Fifteen 1-yr old roosters were employed in order to investigate the influence of various dietary fibers on the water and Na metabolism of chicken. Wheat bran, pure cellulose and ground rice straw replaced corn in the control diet at 10% level; Pectin replaced corn at 8% level. Three roosters were allotted per dietary treatment and one rooster per replicate. The limit of probability accepted as being significant was P$\leq$.05. The dry matter metabolizabilities of cellulose and rice straw diets were significantly lower, and those of control and pectin diets were significantly higher than that of the wheat bran diet. Pectin fed roosters seemed to drink more water than did the other birds. Also, excreta from roosters fed the pectin diet were significantly wetter than those from other treatments. However, no difference in water intake and fecal moisture were found when !he roosters were colostomized. It was also found that the colostomized birds drank more water than did intact ones. Data of water holding capacity and bulk density of dried excreta showed that cellulose, rice straw and wheat bran in decreasing order were strong in fibrous property. There were no significant differences in C$_{Na+}$ , Cosm and C$_{{H_2}O}$ among all treatments. When the values of urine volume, urine osmolality and C$_{{H_2}O}$ were put together, it can be concluded that 11 out of 15 roosters developed diuresis. More severe diuretic symptoms were developed in roosters when they were fed more fibrous diets. In conclusion, when the four dietary fibers were graded in terms of fibrous property, it turned out to be pectin, cellulose, rice straw and wheat bran in decreasing order.

• Proceedings of the Korea Water Resources Association Conference
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• 2015.05a
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• pp.509-509
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• 2015

물 수요관리측면에 대한 정책을 수립하기 위해서는 현재 또는 장래에 대한 용수수급의 정확한 이해를 필요로 한다. 이를 위해서는 용수 수요량 및 공급량뿐만 아니라 여러 산정요소를 필요로 하는데, 그 중 회귀수량은 물이 이용되고 다시 하천으로 회귀되어 이용될 가능성이 있는 수량으로 정의되며, 용수수급 및 용수절약 측면에서 회귀 수량은 중요한 요소라 할 수 있다. 회귀수량 조사는 유역조사 사업 이래, 10년간 생?공용수를 중심으로 미시적, 거시적으로 조사를 시행하였으나, 측정 자료의 신뢰도, 조사방법 및 지점선정 등의 문제로 인하여 조사 성과의 활용성이 매우 낮은 실정이다. 수자원장기종합계획등에서는 수자원관련 계획 수립시 생?공용수의 회귀율을 65 %로 적용하고 있으나, 이는 1970년대 말의 사회적 여건 및 경제적 상황이 반연된 결과로 현재 상황에 적용되기 곤란하다. 따라서, 현재 실정에 맞는 회귀율 산정은 반드시 필요하게 된다. 본 연구에서는 기존 생활용수 회귀수량 산정 연구 한계를 보완하고 유역조사 시행을 위한 개선된 회귀수량을 산정하고자 한다. 본 연구는 서울시 중랑물재생센터 처리구역을 기반으로 중랑천유역을 시험유역으로 선정하였다. 기존 회귀수량 산정방법을 개선하기 위해 시험유역 회귀수량 산정을 위한 가용 자료 분석 및 용수흐름 네트워크 공간분석을 추가로 진행하였다. 가용자료로 시험 유역내 상수공급자료(정수장 공급량, 상수계통도, 유수 및 누수율), 하수처리자료(하수처리구역도, 하수처리계통도, 유입량 및 방류량) 및 기상자료(기상청 지점 및 AWS 강우자료)를 구축하였고 각각의 상수계통도 및 하수처리계통도로부터 용수 흐름 네트워크망을 구축하였다. 상수공급자료로부터 상수계통도 공급지역을 구분하여 월별 유수율에 따른 월별 실 공급량을 산정하였다. 하수처리자료로부터 시험유역에서의 월별하수처리 유입량 및 방류량을 산정하였다. 최종적으로 회귀율(하수처리 방류량/실 공급량)을 산정한 결과 연평균 회귀율은 각각 93.97 %(2011년), 95.02%(2012년)로 과잉 추정 되었으며 7 ~ 9월의 회귀율은 110 ~ 120 %로 유입량을 초과하였다. 이는, 하수처리로 유입되는 유입량의 하수관거는 합류식으로 구축되어 7 ~ 9월에 많은 양의 강우량이 우수관을 통해 하수처리장으로 이송되어 생활용수 이외에 자연적인 공급량으로 인한 것으로 분석되었다. 따라서, 월별 회귀율 산정을 위해서는 불투수층에서의 면적강우량(mm)을 유입량(m3/s)으로 환산된 값을 고려하여 회귀율을 재산정하였다. 그 결과 연평균 회귀율은 각각 78.27 %(2011년), 77.58 %(2012년)로 나타났다.각각의 월별 회귀율도 매우 유사하게 나타났으며 과거 관용적으로 사용된 65 % 회귀율보다 약 12 ~ 13%로 증가하였으며 이는, 하수처리시설 구축 및 처리효율의 증가와 상수처리시설의 관로시설의 개량으로 인한 유수율 및 누수율 감소로 회귀율이 증가한 것으로 판단된다.

• Journal of the Korea Concrete Institute
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• v.25 no.1
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• pp.99-106
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• 2013

Concrete materials subjected to impact by high velocity projectiles exhibit responses that differ from those when they are under static loading. Projectiles generate localized effects characterized by penetration of front, spalling of rear and perforation as well as more widespread crack propagation. The magnitude of damage depends on a variety of factors such as material properties of the projectile, impact velocity, the mass and geometry as well as the material properties of concrete specimen size and thickness, reinforcement materials type and method of the concrete target. In this study, penetration depth of front, spalling thickness of rear and effect of spalling suppression of concrete by fiber reinforcement was evaluated according to compressive strength of concrete. As a result, it was similar to results of the modified NDRC formula and US ACE formula that the more compressive strength is increased, the penetration depth of front is suppressed. On the other hand, the increase in compressive strength of concrete does not affect spalling of rear suppression. Spalling of rear is controlled by the increase of flexural, tensile strength and deformation capacity.

• Journal of the Korean Society for Nondestructive Testing
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• v.33 no.5
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• pp.443-451
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• 2013

Acoustic emission(AE) has emerged as a powerful nondestructive tool to detect any further growth or expansion of preexisting defects or to characterize failure mechanisms. Recently, this kind of technique, that is an in-situ monitoring of inside damages of materials or structures, becomes increasingly popular for monitoring the integrity of large structures like a huge wind turbine blade. In this study, the activities of AE signals generated from external artificial sources was evaluated and located by new developed signal mapping source location method and this test is conducted by 750 kW full-scale blade. And a new source location method was applied to assess the damage in the wind turbine blade during step-by-step static load test. In this static loading test, we have used a full scale blade of 100 kW in capacity. The results show that the acoustic emission activities give a good agreement with the stress distribution and damage location in the blade. Finally, the applicability of the new source location method was confirmed by comparison of the result of source location and experimental damage location.

• Journal of the Korean Society for Railway
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• v.20 no.3
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• pp.311-319
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• 2017

The primary suspension system of a railway vehicle restrains the wheelset and the bogie, which greatly affects the dynamic characteristics of the vehicle depending on the stiffness in each direction. In order to improve the dynamic characteristics, different stiffness in each direction is required. However, designing different stiffness in each direction is difficult in the case of a general suspension device. To address this, in this paper, an optimization technique is applied to design different stiffness in each direction by using a conical rubber spring. The optimization is performed by using target and analysis RMS values. Lastly, the final model is proposed by complementing the shape of the weak part of the model. An actual model is developed and the reliability of the optimization model is proved on the basis of a deviation average of about 7.7% compared to the target stiffness through a static load test. In addition, the stiffness value is applied to a multibody dynamics model to analyze the stability and curve performance. The critical speed of the improved model was 190km/h, which was faster than the maximum speed of 110km/h. In addition, the steering performance is improved by 34% compared with the conventional model.

• The Korean Journal of Pesticide Science
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• v.14 no.4
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• pp.478-489
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• 2010

Penthiopyrad is a fungicide agent in types of pyrazole which is showing the effect of prevention in fungal disease and powdery mildew. In order to register this new pesticide, reports of acute toxicity and chronic toxicity by animal study were examined to set acceptable daily intake to evaluate hazards of consumers. Acute toxicity was low in toxic, and it did not have the effect of acute dermal toxicity, acute eye irritation, or skin sensitization. As the result of the study in chronic toxicity, the common effect of chemical appeared in the liver and thyroid which was proven as a toxic effect. Two-generation reproduction toxicity, genotoxicity, and prenatal development toxicity were not proven. As the result of carcinogenic study, increase of thyiroid follicular adenoma in the rat and the frequency of liver hepatocellar adenoma in mice were also increased. However, it was decided that the threshold value on the effect in chemicals could be controlled through study liver enzyme induction. Therefore, the ADI for penthiopyrad is 0.081 mg/kg/ bw/day, based on the NOAEL of 8.10 mg/kg bw/day of twelve-months dogs study and applying an uncertainty factor of 100.

• Fire Science and Engineering
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• v.28 no.3
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• pp.10-19
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• 2014

The fast evacuation from fire floors to evacuation floors in high-rise building fires can minimize the human damage. In this study, an evacuation instrument, which are applicable to the high-rise buildings of adaptable escape mechanisms by the current NFSC 301 (national fire safety code 301), were selected to analyze the applicability in the high-rise buildings over 11th floor through the site adaptability test. The results of the site test were as follows. The elevator type evacuation instrument of new concept developed as a new technology by compensating the defect of evacuation instrument limiting in the high-rise buildings over 11th floor had completed the stability test and the performance certification test in fire stations, which there were no problems in the introduction of the elevator type evacuation instrument as an escape mechanism in the high-rise buildings. The elevator type evacuation instrument using escapers' weight without using electric power was an escape mechanism that many people could evacuate in a short period of time when a fire broke out in the high-rise buildings. In particular, The elevator type evacuation instrument operated by nonpower had the adaptability as a customized escape mechanism considering user characteristics in the buildings for the disabled or patients with an advanced disease.

• Korean Journal of Food Science and Technology
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• v.3 no.1
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• pp.19-24
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• 1971

The Korean rice, Nonglim # 6 was milled into brown rice and 92% polished one and packed with the kraft paper bags. The sample, bags were irradiated with the respective doses of 30, 50, 600 and 800 Krad and then were stored at $10^{\circ}C$ and 75% RH. Changes of fat acidity, amylase activity, viscosity of thus irradiated rice were examined during storage. The results were as follows. 1) Fat acidity increased slightly in the range of $30{\sim}50$ Krad but remarkably in the range of $600{\sim}800$ Krad. However, the rate of increase was low in comparison with the storage under the room temperature. 2) The amylase activity of both the low dose lot and the control decreased in the same rate during the storage. However the high dose lot had more remarkable decrease of the amylase activity from the beginning. 3) The viscosity by Brabender amylogram showed the slightly decreasing tendency in both the low $30{\sim}50$ Krad lot and the control lot of the polished rice powder during storage. On the other hand, the high dose lot of 600 or 800 Krad marked the similar decreasing rate but by far the lower values of the viscosity. 4) The results of the organoleptic test presented no differences between the low dose lot and the control lot, but the high dose lot and the control lot differed significantly only in the color.

• Journal of the Korean Society of Groundwater Environment
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• v.1 no.2
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• pp.113-120
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• 1994

One of the delicate problems in aquifer management is the identification of the spatial distribution of tile hydrological parameters. The observed data are insufficient to identify the distribution of transmissivities in LAN aquifer. To determine the distribution of the transmissivity in LAN aquifer, it would be required to transform the observed heads at the pilot points into transmissivities. Therefore, three procedures wire tackled for the identification of the spatial distribution of the hydrological parameters; geostatistical estimate of the parameter field on the basis of known well point, heads reconstructed by a numerical model, and modification of the values at pilot points by a minimization algorithm. The variogram of Kriging has been applied to a total of 258 transmissivity value in attempt to quantify their distribution of LAN aquifer. Variogram of the observed and optimized transmissivities at pilot points are adapted to the exponential form. So, it is fitted by theoretical one with coefficients of w=0.623, a=2.743. Values of head obtained through numerical analysis are adjusted to the observed values so that heads have been transformed completely into the transmissivities at the observation wells. The procedure represented contour map of the estimated transmissivities and the calculated head.

• Journal of the Korea Organic Resources Recycling Association
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• v.7 no.1
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• pp.23-30
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• 1999

The changes of soil physico-chemical properties were investigated in the sandy loam soil amended with various application rates of chicken and pig manure composts. After repeated application of the composts for 3 years, total nitrogen content in soil treated with applied 120Mg/ha of chicken and pig manure composts was 2.1 g/kg equally. Organic matter content was 38.8 and 39.1 g/kg, available phosphate content was 602 and 585 mg/kg, and cation exchange capacity(CEC) was 10.1 and 12.4 cmol/kg in chicken and pig manure compost 120 Mg/ha treatment, respectively. Exchangeable K, Ca, Na, Mg contents, and electrical conductivity(EC) increased with the amount of applied compost. Also, with increased amount of applied compost, porosity of soil increased, but hardness, bulk density and Y value decreased.