• Asian-Australasian Journal of Animal Sciences
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• v.20 no.2
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• pp.237-244
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• 2007

An experiment was conducted to study the growth performance, bone mineralization and mineral excretion in broiler starter chicks fed high levels of cholecalciferol (CC) at sub-optimal levels of calcium (Ca) and non-phytate phosphorus (NPP). Five hundred and sixty day-old Vencobb female broiler chicks were housed in raised wire floor stainless steel battery brooder pens ($24"{\times}30"{\times}18"$) at the rate of five chicks per pen. A maize-soyabean meal basal diet was supplemented with dicalcium phosphate, oyster shell powder and synthetic CC to arrive at two levels each of Ca (0.50 and 0.60%), and NPP (0.25 and 0.30%) and four levels of CC (200, 1,200, 2,400 and 3,600 ICU/kg) in a $2{\times}3{\times}4$ factorial design. Each diet was fed ad libitum to chicks in 7 pens from 2 to 21days of age. Body weight gain, feed intake and bone weight increased (p<0.05) with increase in level of CC at both the Ca and NPP levels tested. The CC levels required to obtain significant improvement in body weight gain and feed intake reduced (2,400 ICU/kg vs. 1,200 ICU/kg) with increase in levels of P in diet (0.25% vs. 0.3%, respectively). The feed conversion ratio was significantly improved (p<0.05) with increase in level of CC from 200 to 1,200 ICU/kg diet at 0.5% Ca, while at 0.6% Ca, the level of CC in diet did not influence the feed efficiency. Tibia mineralization (density, breaking strength and ash content) and Ca and P contents in serum increased significantly (p<0.05) with increase in levels of CC in diet. The CC effect on these parameters was more pronounced at lower levels of Ca and NPP (0.5 and 0.25%, respectively). The data on body weight gain and feed intake indicated that NPP level in diet can be reduced from 0.30 to 0.25% by increasing CC from 200 to 2,400 ICU/kg. Similarly, the bone mineralization (tibia weight, density and ash content) increased non-linearly (p<0.01) with increase in CC levels in diet. Concentrations of P and Mn in excreta decreased (p<0.01), by increasing CC level from 200 to 2,400 ICU/kg diet. It can be concluded that dietary levels of Ca and NPP could be reduced to 0.50 and 0.25%, respectively by enhancing the levels of cholecalciferol from 200 to 2,400 ICU/kg with out affecting body weight gain, feed efficiency and bone mineralization. Additionally, phosphorus and manganese excretion decreased with increase in levels of CC in broiler diet.

• Asian-Australasian Journal of Animal Sciences
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• v.17 no.9
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• pp.1214-1218
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• 2004

Data on 958 Karan Fries (KF) and 780 Karan Swiss (KS) cows, born during 1974 to 1992 at National Dairy Research Institute, Karnal were evaluated for causes of culling and their impact on milk performance and herd strength. Causes of culling were classified as voluntary culling (low milk yield) and involuntary culling (other than milk yield). The milk yield of cows was evaluated inretrospectively by estimating expected breeding value (EBV) on the basis of first lactation yield (FLY) and all available lactation yield (ALY). The culling rate of KF cows over the years varied from 10.89 (1988) to 33.92% (1991) with an overall average of 20.96% and in KS from 19.91 (1984) to 33.74% (1989) with an overall average of 25.01%. Reproductive disorders, teat and udder problems, low milk production, health and locomotive disorders were the major reasons of culling accounted respectively for 5.56, 4.97, 4.61, 3.18 and 2.24% of herd strength in KF cows. The corresponding causes of culling were 6.20, 6.26, 7.69, 1.49 and 2.67% of herd strength in KS cows. The involuntary culling of cows accounted for 82.4% in K F and 76.1% in KS cows of total culling. The average annual disposal rate in KF and KS was 26 and 30% whereas annual replacement rate was 24 and 26% respectively. The EBV of involuntary culled cows on the basis of FLY and ALY was 3,111 and 3,515 kg in KF; and 2,669 and 2,940 kg in KS cows respectively. The EBV of selected cows on the basis of FLY and ALY was 3,242 and 3,549 kg in KF and 2,893 and 3,245 kg in KS cows respectively. The average breeding value of involuntary culled cows was not significantly different from selected cows in both the herds. The high rate of involuntary culling of potential cows might be major factor responsible for declined performance and size in these herds. The results indicated that higher genetic gain (2.14% of herd average in KF and 3.49% of herd average in KS) could be obtained by restricting the involuntary culling (50% of total culling) through improved management practices and increasing replacement rate.

• Korean Journal of Community Nutrition
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• v.3 no.2
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• pp.190-201
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• 1998

This study was carried out with 505(243 boys and 262 girls in the Sungnam area) high school students to investigate the effects of eating behavior and anthropometric variables of weight and height on excercise performance. General characteristics about subjects and eating behavior were surveyed by questionnaire, anthropometric data were collected using two methods. The weight and height of subjects in 1996 were measured, but the same data in 1995 were collected from health records of each student. Body fat content of subjects was measured by BIA(Body Impedance Analysis). The grades of exercise performance, which were evaluated by physical education teachers were collected from records of a physical strength test score of each subject. From these, the following result were found. Groups with different eating behaviors such as skipping meals, overeating, food preference for a specific food(milk, carbonated drink etc.) were significantly different in their weight and height and body fat contents. The growth rate of height in first and second grade boys was significantly higher than that for grade boys. The amount of weight gain from second grade to third grade was significantly more than that of other grades both for boys and girls. The mean of BMI was $21.66\pm{2.95}$ in boy, $21.50\pm{2.62}$ in girls. The percentage of body fat was $24.91\pm{6.55%}$ in boy $34.73\pm{4.88%}$ in girls. Amounts of body fat were significantly increased in third grade. The group with higher fat content and the higher BMI group had lower values of physical strength. And the ability to exercises perform decreased significantly by promotion of grade. The other variables such as degree of concern about weight control and preference of exercise, and frequencies of exercise per week were significant factors in body fat content and physical strength. As a countermeasure for these problems, nutrition and health education must be developed for adolescents and a practical, proper physical activity guidance campaign for them is necessary.

• Architectural research
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• v.11 no.1
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• pp.25-33
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• 2009

This study presents the testing of 15 hwangtoh-based cementless concrete mixes to explore the significance and limitations of the development of eco-friendly concrete without carbon dioxide emissions while maintaining various beneficial effects. Hwangtoh, which is a kind of kaolin, was incorporated with inorganic materials, such as calcium hydroxide, to produce a cement-less binder. The main variables investigated were the water-to-binder ratio and fine aggregate-to-total aggregate ratio to ascertain the reliable mixing design of hwangtoh-based cementless concrete. The variation of slump with elapsed time was recorded in fresh concrete specimens. Mechanical properties of hardened concrete were also measured: including compressive strength gain, splitting tensile strength, moduli of rupture and elasticity, stress-strain relationship, and bond resistance. In addition, mechanical properties of hwangtoh-based cement-less concrete were compared with those of ordinary portland cement (OPC) concrete and predictions obtained from the design equations specified in ACI 318-05 and CEB-FIP for OPC concrete, wherever possible. Test results show that the mechanical properties of hwangtoh-based concrete were significantly influenced by the water-to-binder ratio and to less extend by fine aggregate-to-total aggregate ratio. The moduli of rupture and elasticity of hwangtoh-based concrete were generally lower than those of OPC concrete. In addition, the stress-strain and bond stress-slip relationships measured from hwangtoh-based concrete showed little agreement with the design model specified in CEB-FIP. However, the measured moduli of rupture and elasticity, and bond strength were higher than those given in ACI 318-05 and CEB-FIP. Overall, the test results suggest that the hwangtoh-based concrete shows highly effective performance and great potential as an environmental-friendly building material.

• Korean Journal of Food Science and Technology
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• v.24 no.2
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• pp.160-164
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• 1992

Cooking, texture and sensory properties of sweet potato Tangmyon (starch noodle), common Tangmyon (50% sweet potato starch+50% corn starch) and corn Tangmyon were evaluated. The weight gain of Tangmyon showed a linear relationship with the square root of cooking time, in which the common Tangmyon showed the highest value. The solid loss during cooking was the highest in common Tangmyon followed by corn Tangmyon. The sweet potato Tangmyon showed the highest value for compression strength and stretching ratio, but lowest value for elongation elastic modulus. At the same compression strength, corn Tangmyon had the highest tensile strength and sweet potato Tangmyon the lowest value. Sweet potato Tangmyon showed the highest sensory scores of gloss, clarity, adhesiveness, gumminess, extensibility and overall desirability, and corn Tangmyon the lowest scores. Except adhesiveness (by appearance) and the gumminess of common and corn Tangmyon, significant differences (p<0.05) were observed for other sensory properties among samples.

• Advances in biomechanics and applications
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• v.1 no.2
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• pp.95-109
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• 2014

Peri-acetabular bone ingrowth plays a crucial role in long-term stability of press-fit acetabular cups. A poor bone ingrowth often results in increased cup migration, leading to aseptic loosening of the implant. The rate of peri-prosthetic bone formation is also affected by the polar gap that may be introduced during implantation. Applying a mechano-regulatory tissue differentiation algorithm on a two-dimensional plane strain microscale model, representing implant-bone interface, the objectives of the study are to gain an insight into the process of peri-prosthetic tissue differentiation and to investigate its relationship with implant-bone relative displacement and size of the polar gap. Implant-bone relative displacement was found to have a considerable influence on bone healing and peri-acetabular bone ingrowth. An increase in implant-bone relative displacement from $20{\mu}m$ to $100{\mu}m$ resulted in an increase in fibrous tissue formation from 22% to 60% and reduction in bone formation from 70% to 38% within the polar gap. The increase in fibrous tissue formation and subsequent decrease in bone formation leads to weakening of the implant-bone interface strength. In comparison, the effect of polar gap on bone healing and peri-acetabular bone ingrowth was less pronounced. Polar gap up to 5 mm was found to be progressively filled with bone under favourable implant-bone relative displacements of $20{\mu}m$ along tangential and $20{\mu}m$ along normal directions. However, the average Young's modulus of the newly formed tissue layer reduced from 2200 MPa to 1200 MPa with an increase in polar gap from 0.5 mm to 5 mm, suggesting the formation of a low strength tissue for increased polar gap. Based on this study, it may be concluded that a polar gap less than 0.5 mm seems favourable for an increase in strength of the implant-bone interface.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.41 no.2
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• pp.101-111
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• 2021

Two different types of shear-friction tests were classified by external loadings and referred to as a push-off and a pull-off test. In a pull-off test, a tension force is applied in the transverse direction of the test specimen to produce a shear stress at the shear plane. This paper presents a method to evaluate shear transfer strengths of uncracked pull-off specimens. The method is based on the compression field theory and different constitutive laws are applied in some ways to gain accurate shear strengths considering softening effects of concrete struts based on Modified Compression Field Theory (MCFT) and Softened Truss Model (STM). The validity of the proposed method is examined by applying to some selected test specimens in literatures and results are compared with the predicted values. A general agreement is observed between predicted and measured values at ultimate loading stages in initially uncracked pull-off test specimens. A shear strength evaluation formula considering the effective compressive strength of a concrete strut was proposed, and the applicability of the proposed formula was verified by comparing with the experimental results in the literature.

• Journal of the Korean Wood Science and Technology
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• v.51 no.6
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• pp.542-554
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• 2023

This study is a continuation of our previous work, which focused on the resistance of jabon wood to termites after impregnation with wood vinegar (WV) and animal-based adhesive (kak). This paper presents the physicomechanical properties of fast-growing jabon wood impregnated with kak at two concentrations (8% and 10%) in wood vinegar or water as a solvent with and without 4% borax. The physical properties of the impregnation solution, that is, viscosity, density, pH, and solid content, were evaluated according to SNI 06-4567-1998. Some physical parameters, such as weight percent gain (WPG), density, water uptake, anti-swelling efficiency (ASE), crystallinity, and mechanical properties, i.e., modulus of elasticity (MOE), modulus of rupture (MOR), and compression strength parallel to the grain (CS), of the impregnated wood were determined. Based on these results, wood impregnated using a mixture of kak in WV presented better physical (increased WPG, density, dimensional stability, and crystallinity) and mechanical (increased MOE/MOR and compression strength) properties than wood impregnated with a water solvent or untreated wood. The wood impregnated using WV and water solvent improved the physical and mechanical properties. The density of the wood increased by 44%-58% and 32%-47%, ASE radial-tangential increased by 38%-45%; 15%-28% after 24 h of water immersion, crystallinity increased by 59%-74%; 36%, MOE increased by 46%-57%; 28%-31%, MOR increased by 29%-34%; 14%-27%, and compression strength increased by 40%-76%; 38%-72% values to untreated wood.

• Proceedings of the Korean Geotechical Society Conference
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• 1994.09a
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• pp.175-181
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• 1994

In order to accelerate the rate of consolidation settlement and to gain a required shear strength for a given soft clay deposit, the preloading technique combined with a vertical drainage system has been widely applied. In this study, the theory of axisymmetric concolidation, which considers the variation of compressibility and permeability during the consolidation process, has been developed. Smear and well resistance effects are also considered. Furthermore, several back-analysis schemes such as simplex method, BFGS method, and ADS have been adopted in the axisymmetric consolidation program(AXICON). The measured data in the first stage of consolidation are utilized to predict the subsequent consolidation behavior.

• Journal of the Korean Society of Clothing and Textiles
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• v.22 no.4
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• pp.535-542
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• 1998

Cotton fabrics were treated with BTCA, which is used to improve the wrinkle recovery property of cotton fabrics. BTCA, with varying its concentrations, was treated on cotton fabrics by pad dry-cure technique. BTCA contents in treated cotton fabrics were determined by the weight gain and the FT-lR spectrometer. The effects on the sorption and physical properties of BTCA treated fabrics were investigated. IR spectra showed that ester-crosslinks were produced in BTCA treated cotton fabrics. And as increasing the concentration of BTCA, ester-crosslinks are increased in amorphous regions of fabrics. Moisture regain and water imbibition of treated fabrics were reduced. But, they were increased over a certain concentration. Dye sorptions also were reduced, but they were similar over 6% BTCA. When BTCA was treated on cotton fabrics, DP rating and wrinkle recovery angle were improved. On the other hand, strength retentions of treated fabrics were lower than untreated fabrics. Stiffness was increased.