• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2002년도 춘계학술대회 논문집
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• pp.745-748
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• 2002

Many malfunctions take place in container crane spreader due to impact. So we designed a 2DOF hydraulic impact absorbing system and studied the change of impulse with respect to the variation of falling height and weight. The falling height becomes higher than 1m and the falling weight goes up heavier than 100kg, the impact absorbing rate was lower. When spreader is bumped against container and impulse force concentrates on one point, impact absorbing equipment would not be operated properly and make some trouble.

• Journal of Nutrition and Health
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• 제30권6호
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• pp.715-726
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• 1997

This study was conducted longitudinally following the total nitrogen , total lipid, and lactose concentrations and their factors on concentrations of energy-yielding nutrients in human milk from 2-5 days to 12 weeks postpartum of 45 lactating Korean mothers. All samples were from well-defined subjects. And uniform collection procedures were used . Total nitrogen concentration of milk decreased significantly from 385mg/이 at 2-5 days to 201mg/dl at 12 weeks postpartum. Total lipid concentration increased from 1.98g/dl at 2-5 days to 3.09g/dl at 12 weeks postpartum. However, there was a large variation in the concentration of total lipids. Lactose concentration increased signifciantly from 6.53g/dl at 2-5 days to 7.48g/dl at 12 weeks. Total nitrogen concentration in milk was positively related to pregnancy weight gains at 2 and 6 weeks postpartum. Total lipid concentration was positively related to infant birth weight : however, it was negatively related to the maternal weight loss. In addition, total lipid concentration was positively related to parity and maternal percentage body fat at 12 weeks postpartum. Milk lactose concentration was positively related to parity at 2 weeks postpartum.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1999년도 봄 학술발표회 논문집(I)
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• pp.187-190
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• 1999

This study is intended to present the properites of planting concrete using the light-weight aggregate and crushed aggregate. According to the result of experiment, the concrete using orchid stone shows a better performance in voids volume, unit weight, absorbtion, thermal conductivity and pH, which are helpful for planting and heat isolation. Therefore, if planting concrete used with orchid stone are utilized to be the planting base on the building's roof, it will be effective to reduced the cost of construction and heating due to the redution of building's self weight and heat isolation effection.

• Elastomers and Composites
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• 제34권4호
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• pp.292-298
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• 1999

Lactide oligomer with number averagae molecular weight of 460 was synthesized and reacted with poly(oxyteramethylene)glycol(PTMG, Mn = 650) to obtain oligolactide oligomer-terminated PTMG. Polyurethanes were synthesized from the oligolactide-terminated PTMG, 4,4'-diphenylmethane diisocyanate, and 1,4-butanediol. The mechanical and thermal properties of the polyurethanes and PTMG based polyurethane as control were measured by means of DSC and tensile tester. Degradation behavior of these polyurethanes put into a compost was evaluated by variation of mechanical properties, surface state, and weight loss. Modulus and weight significantly decreased with increasing time. The surface of the oligolactide polyurethane put into the compost during 6 weeks had a number of voids. On the other hand, These properties of the PTMG based polyurethane as control did not change. These results suggest that the novel polyurethanes incorporated oligolactide easily degrade under biodegradable condition.

• 한국언어정보학회지:언어와정보
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• 제13권1호
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• pp.39-56
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• 2009

This paper investigates ordering alternation phenomena in Korean using the dative construction data from Sejong Corpus of Modern Korean (Kim, 2000). The paper first shows that syntactic weight and information structure are distinct and independent factors that influence word order in Korean. Moreover, it reveals that heaviness and givenness compete each other and exert diverging effects on word order, which contrasts the converging effects of these factors shown in word orders of right-branching languages like English. The typological variation of syntactic weight effect poses interesting theoretical and empirical questions, which are discussed in relation to processing efficiency in ordering.

• 한국초지조사료학회지
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• 제14권2호
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• pp.120-124
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• 1994

Browse from oriental white oak(Quercus aliena Blume) was analysed for nutritive value and biomass estimation. The content of cmde protein was high on August and September. NDF, ADF and lignin contents were increased with progressing the seasons but IVDMD, TDN, DE and ME levels were not different from the variation of seasons. Tannin content was high on May and June. Basal stem diameter $\times$ height of tress was highly correlated with browse dry weights(r=0.80**) and the linear regression equation are the follows; Y = 8.23 + O.57X(Y = browse dry weight(g), X= basal stem diameter $\times$ height(cm)). Using the traditional cutting method, the amounts of browse was determined as 823 g dry weight per tree, while the new method by the above equation gave a similar results, i. e., 793 g dry weight per tree. The possibility of browse biomass estimation of oriental white oak by the basal stem diameter $\times$ height index was found.

• 한국안전학회지
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• 제29권3호
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• pp.14-19
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• 2014

The global demand for reduction in the weight of automobiles has led many countries to focus on the development of hybrid, eco-friendly, and electric cars. Reduction in the weight of materials can both increase fuel efficiency and maximize automobile performance. Therefore, the design of automobile should be inclined towards the safety aspects. but at the same time, it also consider reducing the structural weight of an automobile. In this study, CFRP side members with circular and double hat shaped section was manufactured. The impact collapse tests performed with change of the stacking condition, such as variation of interface number and outerlayer angle. The impact collapse load and absorbed energy were quantitatively analyzed according to the changes in section shapes and stacking condition. This analysis was performed to obtain design data that can be applied in the development of optimum lightweight members for automobiles.

• 센서학회지
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• 제13권1호
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• pp.1-11
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• 2004

Due to various types of errors added to dynamic weight measurement data, proper methods to reduce measurement errors are required to produce reliable weights. To cope with parasitic types of errors in real systems, information provided by the various sensors is utilized and combined in such a way to reduce the measurement errors of load cells. In addition to four channels of load cells from a trailer, an accelerometer is used to obtain the information to compensate the error induced from vertical movement of the vehicle due to the variation of ground level. A model trailer system is run to verify the effectiveness of the proposed method to reduce noise of dynamic weight measurements. Experiments show that the processed error magnitudes of less than 20 g can be obtained for 10 Kg experimental loads.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2004년도 추계학술대회논문집
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• pp.79-82
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• 2004

In general, compressors for refrigerators are major noise source in home environment. The vibration originated from a pump of a compressor can make noise through suspension springs and a LDT(Line Discharge Tube). Especially for the inverter motor driven compressor, the vibration is more serious than it of the constant speed compressors. Because the operation frequency range of an inverter motor driven compressor is very wide from 1600 rpm to 4200 rpm. In this paper, we propose the numerical model to reduce vibration by designing weight balancers and grommets. Results for analytical investigations on the exciting force and moment at the pump mass center, weight balancers and exciting frequency variation are presented.

• 소음진동
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• 제10권1호
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• pp.97-106
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• 2000

The dynamic behavior of crankshaft-bearing system in scroll compressor has been investigated using the combined methodologies of finite elements and transfer matrices. The finite element formulation is proposed including the field element for a shaft section and the point element at balancer weight locations, bearing locations, etc., whereas the conventional method is used with the elements. The Houbolt method is used to consider the time march for the integration of the system equations. The linear stiffness and damping coefficients are calculated for a finite cylindrical fluid-film bearing by solving the Reynolds equation, using finite difference method. The orbital response of crankshaft supported on the linear bearing model is obtained, considering balancer weights of motor rotor. And, the steady state displacement of crankshaft are compared with a variation in balancer weight. The loci of crankshaft at bearing locations are composed of the synchronous whirl component and the non-synchronous whirl component.