• Asian-Australasian Journal of Animal Sciences
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• 제22권5호
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• pp.747-755
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• 2009

The feed resource for animals is a major cost determinant for profitability in livestock production enterprises, and thus any effort at improving the efficiency of feed use will help to reduce feed cost. Feed conversion ratio, expressed as feed inputs per unit output, is a traditional measure of efficiency that has significant phenotypic and genetic correlations with feed intake and growth traits. The use of ratio traits for genetic selection may cause problems associated with prediction of change in the component traits in future generations. Residual feed intake, a linear index, is a trait derived from the difference between actual feed intake and that predicted on the basis of the requirements for maintenance of body weight and production. Considerable genetic variation exists in residual feed intake for cattle and pigs, which should respond to selection. Phenotypic independence of phenotypic residual feed intake with body weight and weight gain can be obligatory. Genetic residual feed intake is genetically independent of its component traits (body weight and weight gain). Genetic correlations of residual feed intake with daily feed intake and feed conversion efficiency have been strong and positive in both cattle and pigs. Residual feed intake is favorably genetically correlated with eye muscle area and carcass weight in cattle and with eye muscle area and backfat in pigs. Selection to reduce residual feed intake (excessive intake of feed) will improve the efficiency of feed and most of the economically important carcass traits in cattle and pigs. Therefore, residual feed intake can be used to replace traditional feed conversion ratio as a selection criterion of feed efficiency in breeding programs. However, further studies are required on the variation of residual feed intake during different developmental stage of production.

• The Korean Journal of Physiology
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• 제17권2호
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• pp.177-182
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• 1983

In order to clarify the effect of the unilateral pneumonectomy on the compensatory growth of the residual lung, liver and kidney, and serum electrophoresis pattern, right lung pneumonectomy was performed on rabbits under general anesthesia with pentobarbital sodium. On the fifth day after the surgery, the weight of the residual lung, liver and bilateral kidneys was measured and organ weight-body weight ratio was calculated. And in an attempt to know whether the cells in the liver and the kidney were proliferated by unilateral pneumonectomy, DNA content was determined. The quantity(g/100 ml) of serum protein was determined also and serum electrophoresis was performed on cellulose acetate membrane. The results obtained are summarized as following. The weight of the residual lung and lung weight-body weight ratio was significantly increased respectively. The weight of the liver and organ weight-body weight ratio were not changed but the DNA content of the liver and kidney tissue increased significantly, illustrating that unilateral pneumonectomy caused cellular hyperplasia in the liver and in the kidney as well as in the residual lung. The quantity(g/100 ml) of serum protein was significantly increased and in the analysis of the electrophoregram, there was significant difference between the normal and pneumonectomy group. Taken together, these results indicate that unilateral pneumonectomy caused the compensatory hyperplasia of the liver, the kidney and the residual lung as well as the change of electro-phoretic pattern. And it also suggests that a humoral factor, which proliferates the cells in the residual lung, the liver and the kidney, existed in the pneumonectomized rabbits.

• Journal of Welding and Joining
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• 제35권1호
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• pp.55-60
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• 2017

There are many Industry Code and Standard (ICS) for Structural Integrity Assessment (SIA) on welded structure with defect. The general ICSs, such as R6, BS 7910 and API 579-1/ASME FFS-1, provide equations to determine the upper bound residual stress profiles based on collections from many literatures. However, these residual stress profiles used in the SIA cause the conservative design for welded structures. In this study, the structural integrity assessment for girth weld in pipeline has been conducted based on fracture mechanics. In addition, thermo-elastic plastic FE analysis was performed for evaluating the residual stress of girth weld in pipeline. The weight function solution is used to determine the stress intensity factor using the residual stress profile obtained by the FE analysis. This approach can account for redistribution and relaxation of residual stress as the defects grow. In order to the evaluate quantitative comparison between BS 7910 and weight function solution, structural integrity assessment determining allowable crack size on cracked pipe was performed with failure assessment diagram.

• Journal of Welding and Joining
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• 제18권5호
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• pp.33-40
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• 2000

Fatigue crack propagation life of weld toe crack through residual stress field was estimated with Elber's crack concept. Propagation of weld toe crack is heavily influenced by residual stress caused by welding process, so it is essential to take into account the effect of residual stress on the propagation life of weld toe crack. Fatigue crack at transverse and longitudinal weld toe was studied respectively, which represent typical weld joint in ship structure. Numerical and experimental studies are performed for both cases. Residual stress near weldment was estimated through nonlinear thermo-elasto-plastic finite element method, and residual stress intensity factor with Glinka's weight function method. Effective stress intensity factor was calculated with Newman-Forman-de Koning-Henriksen equation which is based on Dugdale strip yield model in estimating crack closure level U at different stress ratio. Calculated crack propagation life coincided well with experimental results.

• 한국군사과학기술학회지
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• 제8권3호
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• pp.101-110
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• 2005

In this paper, the experiments have been conducted to measure the residual velocity for 3.5g steel ball perforating light weight metal plates of aluminum alloy and magnesium alloy. Non-contact electro-magnetic sensors were used to measure the velocity of steel ball before/after perforating plates. The thicknesses of specimens used were about 2.8mm and 4.8mm. The impact velocities of steel ball were from 662m/s to 3594m/s. With same conditions, numerical analysis using Autodyn 2D has been conducted. The results of numerical analysis corresponded with those of experiments. Also, It is suggested that the difference between the residual velocity of experiment or numerical analysis and that of THOR experimental equation of BRL grew smaller as the impact velocity were increased.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2012년도 추계 학술논문 발표대회
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• pp.99-100
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• 2012

Aggregate thermal properties and cooling methods are most important to evaluate the residual mechanical properties of concrete. In this study, we evaluate the residual mechanical properties of concrete according to the aggregate type and cooling method. We use the normal weight aggregate and light weight aggregate which have different thermal properties. After heating to the target temperature, we evaluate the mechanical properties according to the slow and fast cooling condition. As a result, normal weight aggregate concrete has higher effectiveness of cooling conditions than light weight aggregate concrete.

• 한국의류산업학회지
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• 제7권1호
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• pp.111-114
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• 2005

In this the study, polyester/cotton(P/C) blended fabrics with fine denier were developed to get the light weight compared with the traditional P/C blended fabrics. Moreover, the width of the fabrics was extended by the tenter during the final heat treatment to get the lower fabric density and lighter weight. Then, the physical properties of these fabrics were analysed. The results were as the follows: The developed fabrics had 22.6-31.6% lighter weight than the traditional fabrics with the same fabric width. The weight of fabric decreased drastically with the fabrics width down to 67.1 $g/m^2$. The fabric density for the warp direction decreased with the fabric width. The tenacity and the elongation of the developed fabrics was little lower than that of the traditional fabrics. The air permeability of the developed fabrics increased with that of the traditional fabrics. The stretch rate of the developed fabrics decreased with increasing the fabric width. Residual stretch rate of the developed fabrics was more stable than that of the traditional fabrics. Residual stretch rate of the developed fabrics increased with the fabric width, but the highest value was less than 5% which is quit stable.

• Environmental Engineering Research
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• 제10권4호
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• pp.155-164
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• 2005

This study investigated the possibility of reducing the residual aluminum (Al) in the treated water using polymers. Two raw waters (lake and river water) and three kinds of polymers (coagulant, flocculant, and filtration aids) were used for this purpose. This study found that coagulation at the high dose did not necessarily lead to the high concentration of the residual Al in the treated water. The coagulation efficacy was found more important in determining the residual Al than the coagulant dose. The use of a polymer enhanced the removal of turbidity as well as the residual Al. The coagulant aid removed the dissolved Al as well as the particulate Al by helping the coagulation and the solid-liquid separation. The flocculant aid and the filtration aid preferentially removed the particulate Al while helping the solid-liquid separation. The filtration aid reduced the residual Al substantially more effectively than the flocculant aid. The polyamine-based coagulant aid (FL) showed the better performance in reducing the residual Al and turbidity than DADMAC (WT). The cationic flocculant aid with weak charge density and the medium molecular weight (SC-020) showed the best performance in reducing the residual Al.

• Journal of Preventive Medicine and Public Health
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• 제32권1호
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• pp.60-64
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• 1999

환경오염과 관련된 건강효과 연구에서 흡연, 직업 등 교란변수의 영향을 효과적으로 배제할 수 있으면서 폐기능검사가 제대로 시행될 수 있는 연구대상으로 선호되고 있는 특정 연령층인 12세 학동의 보다 정확한 FVC와 FEV1 예측식을 만 들고자 전국 11개 중학교의 학생들(남자 256명, 여자 301명)을 대상으로 측정된 신장, 체중, 그리고 폐기능검사 값으로 신장-체중의 회귀식을 유도하였고, 이를 통해 12세 인구의 신장별 표준체중을 산출하였다. 이 표준체중과 실측체중의 차이인 잔차를 독립변수로 하여 폐기능 예측 식을 남녀별로 만들었는데, 남자의 경우는, FVC(ml) = 50.84 $\times$ 신장(cm) + 7.06 $\times$ 체중 잔차 - 4838.86, FEV1(m1) = 43.57 $\times$ 신장(cm) + 3.16 $\times$ 체증 잔차 4156.66 이었다. 여자에서는 FVC(ml) = 42.57 $\times$ 신장(cm) + 12.50 $\times$ 체중 잔차 - 3862.39, 그리고 FEV1(ml) = 36.29 $\times$ 신장(cm) + 7.74 $\times$ 체중 잔차 - 3200.94 이었다. 이렇게 얻어진 예측값들의 설명력(R2)은 남자에서 FVC, FEV1가 각각 0.708, 0.670이었고, 여자에서는 FVC, FEV1가 각각 0.580, 0.513이었다.

• The Korean Journal of Physiology
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• 제25권1호
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• pp.81-85
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• 1991

At the fifth day after right lung pneumonectomy in New-Zealand white rabbits $(0.8{\sim}1.1\;kg\;B.W.)$, phospholipid and protein concentration in the left lung lavage fluid were measured for clarification of the effect of unilateral pneumonectomy on the secretory function of the type II pneumocytes in growing rabbits. In an attempt to evaluate the effect of unilateral pneumonectomy on the compensatory growth of the residual lung, left lung weight and left lung weight-body weight ratio and DNA concentration, RNA/DNA and total DNA content in the left lung tissue were measured in pneumonectomized and in sham operated control rabbits. The lung weight of pneumonectomized rabbit was approximately two times heavier than that of the control rabbits. DNA concentration and RNA/DNA of the lung tissue were not changed but total DNA content was increased significantly. Phospholipid concentration in the lung lavage fluid of the pneumonectomized rabbits was over two times higher than that of control rabbits. from these experimental results, It is concluded that unilateral pneumonectomy in growing rabbits might cause to increase the secretion of pulmonary surfactant from type II pneumocyte of the residual lung. The cellular hyperplasia seems to be the primary response of the compensatory growing lung in unilateral pneumonectomized growing rabbits.