• Applied Chemistry for Engineering
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• v.16 no.6
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• pp.827-833
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• 2005

This study focused on the establishment of optimum formulation of polyamide based hot melt adhesive through adhesive synthesis, study of physical property, and adhesion study. In the previous study, the optimum formulation of base resins (CM831, 843P) and tackifying resin (terpene resin) was determined. The weight ratio of CM831, 843P, and terpene resin was 75, 25, and 10, respectively. Based on the optimum formulation, the effect of wax and filler addition was examined in this study. According to the results, the maximum adhesion strength with the steel could be obtained by the addition of 5 wt% of polyethylene wax although the melt viscosity of adhesive decreased continuously with the addition of wax. In the case of filler, the optimum adhesion property could be achieved by the addition of 10 wt% of talc. However, the addition of filler caused little increase of melt viscosity of adhesive.

• Journal of Animal Science and Technology
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• v.45 no.3
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• pp.397-408
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• 2003

This study was conducted to examine the feeding effects of FFWBG (fermented feedstuff with wet brewer’s grain) and GS(grinding soybean) in Hanwoo steers. For this research, total twenty steers(average body weight : 455.7$\pm$25.9kg) were grouped into control(formula feed), T1(formula feed:FFWBG=60:40), T2(formula feed:GS=80:20), T3(formula feed:FFWBG:GS=50:40:10), and T4(formula feed: FFWBG:GS=40:40:20), each treatment was allocated to four steers. There was a tendency to be increased average daily gain in T1, T2, T3 and T4 compared with the control even though no statistical significance was found. The feed conversion of T1, T2, T3 and T4 were beneficially better than that of control(P<0.05; 8.25, 9.44, 6.69 and 7.71 vs 11.90, respectively). The blood urea nitrogen concentration of T4 was higher than that of control(P<0.05), but the creatinine concentration of T4 was lower than that of control(P<0.05). The glucose concentration of T1, T2, T3 and T4 were higher than that of control(P<0.05; 59.39, 62.44, 62.17 and 54.00 vs 51.00mg/$d\ell$, respectively). The back-fat thickness of T3 was thicker than that of control, T1, T2 and T4. The rib-eye area of T1, T3 and T4 was wider than that of control. Appearances percentage of ‘A’ ranked meat quantity were 66, 33, 75 and 33% in control, T1, T2 and T4, respectively.

• Food Science and Preservation
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• v.30 no.5
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• pp.875-884
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• 2023

In this study, the quality characteristics of texturized vegetable proteins (TVP) produced from defatted soy flour (DSF) were analytically compared with those of texturized vegetable proteins produced with isolated soy protein (ISP) and non-defatted soy flour (SF). The base raw material formulation consisted of 50% soy proteins, 30% gluten, and 20% corn starch. A cooling die-equipped extruder was used with a barrel temperature set at 190℃ and screw rotation speed of 250 rpm. With respect to the hardness of isolate soy proteins, that of soy flour and defatted soy flour was 22.4% and 68.8%, respectively, and gumminess was 17.6% and 44.3%, respectively. Defatting increased chewiness, shear strength, and springiness. Moisture content was higher in soy flour than in defatted soy flour, while there were no significant differences in terms of water absorption and turbidity. The pH was higher with soy flour than with defatted soy flour. Concerning color, the L and b values were higher with soy flour, while the a value was higher with defatted soy flour. These results suggest that defatting soybeans can improve the quality of plant-based proteins. Further research is needed to address the quality differences from those of isolated soy proteins.

• Journal of the Korea Concrete Institute
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• v.20 no.1
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• pp.67-75
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• 2008

An engineered cementitious composite produced with slag particles (Slag-ECC) had been developed based on micromechanical principle. Base grain ingredients were properly selected, and then the mixture proportion was optimized to be capable of achieving robust tensile ductility in the hardened state. The rheological design is performed in the present study by optimizing the amount of admixtures suitable for self-consolidating casting and shotcreting process in the fresh state. A special focus is placed on the rheological control which is directly applicable to the construction in field, using prepackaged product with all pulverized ingredients. To control the rheological properties of the composite, which possesses different fluid properties to facilitate two types of processing (i.e., self-consolidating and shotcreting processing), the viscosity change of the cement paste suspensions over time was initially investigated, and then the proper dosage of the admixtures in the cement paste was selected. The two types of mixture proportion were then optimized by self-consolidating & shotcreting tests. A series of self-consolidating and shotcreting tests demonstrated excellent self-consolidation property and sprayability of the Slag-ECC. The rheological properties altered through this approach were revealed to be effective in obtaining Slag-ECC hardened properties, represented by pseudo strain-hardening behavior in uniaxial tension, allowing the readily achievement of the desired function of the fresh Slag-ECC. These ductile composites with self-consolidating and shotcreting processing can be broadly utilized for a variety of applications, e.g., in strengthening seismic resistant structures with congested reinforcements, or in repairing deteriorated infrastructures by shotcreting process.

• Journal of Conservation Science
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• v.31 no.4
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• pp.457-476
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• 2015

This study is expected to present instructions and analysis of Modern Dancheong pigments by its physical characteristics. Search pigments currently used and experiments proper mixing ratio of Jangdanyuksaek(Incarnadine). Samples are made by based on presented a mixture ratio which is less exfoliation, cracks and color change. And put into accelerated weathering test and ultraviolet ray degradation test. As a result in case of Jidang($TiO_2$) Rutile type is superior in discoloration and durability. Rutile type makes color difference remarkably because of oil absorption difference while mixing with Jangdan. Water paints which are used as a alternative present yellowness which means water paints lack in durability. whiting should be taken carefully as it has high brightness after degradation.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.22 no.3
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• pp.289-296
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• 2009

Natural frequency is a key parameter to determine the seismic and wind loading of tall flexible structures, and to assess the wind-induced vibration for serviceability check. In this study, natural frequencies and associated mode shapes were obtained from measured acceleration data and system identification technique. Subsequently, finite element(FE) models for a tall reinforced concrete buildings were built using a popular PC-based finite element analysis program and calibrated to match their natural frequencies and mode shapes to actual values. The calibration of the FE model included: 1) compensation of modulus of elasticity considering the mix design strength, 2) flexural stiffness of floor slabs, and 3) major non-structural components such as plain concrete walls. Natural frequencies and mode shapes from the final FE model showed best agreement with the measured values.

• International Journal of Highway Engineering
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• v.12 no.4
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• pp.111-120
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• 2010

This study evaluated strength properties of recycled asphalt concretes using warm-mix technology. Granite with maximum size of 13mm and penetration grade of 80-100 virgin binder were used for mixing in recycled mixtures. Mix design was performed using 20% and 30% RAP(coarse : fine= 6 : 4) contents. GPC, penetration, absolute viscosity and kinematic viscosity were measured for determining ratio of two warm-mix additives (Evotherm and Sasobit). Low-density polyethylene(LD) used as asphalt modifier for improving stiffness of recycled WMA mixtures in this study. Therefore, a total of 11 mixtures were prepared in this study; 8 warm-mix recycled mixtures(2 RAP contents${\times}$2 warm-mix additives${\times}$2 modifiers), 2 hot-mix recycled mixtures and 1 HMA virgin mixture(control). Deformation strength, indirect tensile strength, moisture sensitivity, permanent deformation by wheel tracking tests were measured out for evaluating fundamental properties of recycled asphalt concretes using warm-mix technology.

• Elastomers and Composites
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• v.40 no.2
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• pp.83-92
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• 2005

To develop an automotive fuel hose suitable to the international environmental regulation, FKM rubber materials as an inner material of fuel hole were prepared with different chemical compositions. Measurement of the properties of thermal resistance, oil resistance, fuel resistance, gas permeability including fundamental properties were performed to investigate compatibility for a fuel hose material. Fundamental properties, thermal resistance, oil resistance, fuel resistance and permeability of FKM rubber materials were improved with fluorine content. When the carbon content was 20 phr, FKM compounds with fluorine contents of 66%, 09% and 71% were shown to satisfy the specification oi fuel hose. The gas permeability of NBR and FKM compounds was measured on the mixed fuel oils prepared with isooctane-toluene and gasoline-methanol. FKM rubber materials showed a small difference in penetrated amount of fuel and showed a permeability superior to NBR material. he permeability of FKM rubber materials was not influenced by the contents of fuel oil. Thermal properties of 69% FKM rubber experienced by permeability testing were not variated.

• The Korean Society of Law and Medicine
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• v.17 no.1
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• pp.3-43
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• 2016

The North Korean medical laws are consisted of 'People's Health Act' and 'Medical Act' in the peak of the North Korean constitutional law. Before the legislation of 'People's Health Act', a number of medical laws and regulations existed. But, at present, there is no information about its amendment and effectiveness. 'People's Health Act' legislated in 1980 declared fundamental principles and policies of the North Korean health care system. 'Medical Act' legislated in 1997 is the basic law among the North Korean medical laws. It presented the goals and fundamental principles of the North Korean health care, and then regulated the basics about 'Tests and Diagnosis', 'Medical Treatment', and 'Medical Appraisal'. 'Medical Act' of North Korea was established later than South Korea, and its provisions is smaller in number. And there are lots of abstract and declaratory provisions compare with South Korean 'Medical Act'. Especially there is no provision about the kind and requirements of medical personnel and medical institutions, so it is hard to grasp the North Korean health care system at once. Regarding the medical treatment, there are many similar contents between the North and South Korean 'Medical Act'. But, the provisions, such as regarding mixing the new medicine and the korean traditional medicine, encouraging natural therapies in medical treatment, and informing the patient's protector of bad diagnostic result if there is concern to have a bad influence on patient, are different from the South Korean 'Medical Act'.

• Magazine of the Korea Concrete Institute
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• v.3 no.4
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• pp.133-142
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• 1991

When the behavior of a prototype concrete structure is studied through small-scale model experiments, it is necessary to reproduce all significant physical characteristics on either an one-to-one basis or a specific similitude relationship. Any distortion of similitude must be understood and its effect must be predictable. This paper focuses on improved physical modeling techniques for small-scale reinforced concrete structures. Particular emphasis is placed on the development of a model concrete mix to accurately model the important properties of full-scale prototype concrete. Four types of model reinforcement with different bond characteristics are also studied by testing twenty simple beams. The information obtained will be of immediate use to engineers contemplating small-scale modeling of reinforced concrete structures.