• Economic and Environmental Geology
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• v.9 no.3
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• pp.157-163
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• 1976

In this study, the oil bearing rock-sequence, U-hand-ri Formation (D.S. Lee et al., 1976), was subdivided into three members; the lower, the intermediate and the upper. The lower consists mainly of reddish purple tuff and sandy calcareous shales, the intermediate of an alternation of tuffs, sandstons, calcareous black shales, cherts and limestone and the upper of coarse grained variegated tuff and agglomerate. Oily matter was found from the black shales of the intermediate. Ten samples of black shales from drilled cores, 8 samples of black shales from different outcrops of the member, and 1 sample of grease-like seeping oil from black shales at U-hang-ri coast were chemically analyized. Among them, 9 samples contain remarkable amount of organic carbon (0.96~1.60%) and E.O.M. extract (0.176~0.718%), and mostly the bituminous material is saturated hydrocarbons as well as shown in infared spectroscopic analyses. The elemental analyses of MAE extracts and asphaltenes of some of thoese samples indicate that the transformation of organic material to crude oil is highly progressed. The authors suggest that the seeping oil and oily tinges in black shale layers are the products of natural cracking related with the igneous activities in the area nearby.

• Transactions of the Korean Society of Automotive Engineers
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• v.6 no.3
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• pp.123-137
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• 1998

The finite deformation with self contact problem of C. V. joint boots is analysed by using the implicit finite element code ABAQUS/Standard. It is shown that analysis results have a good agreement with experimental ones to the degree of maximum rotation angle. As an application of design modification, the effects of thickness change of the rounded part of boot model on the bending and the contact situation of deformed geometry are investigated. In this paper, the effect of the design modification in the end on the leakage is examined using 2-D finite element simulation. To solve the leakage problem of grease, the length of the small end is enlarged. From this study, it is confirmed that we can save the cost and time by applying FEM techniques to analyze and design the boot model.

• Journal of the Korean Society for Railway
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• v.8 no.4
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• pp.308-313
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• 2005

In order to successfully propel the stormwater management program, administration plan of stormwater management is enacted in Spring, 2005. Hereafter, in a newly developing area such as a railway station, the best management practices should be established to control the nonpoint pollutant. Construction of a railway station means the increasing of imperviousness rate and lots of nonpoint pollutant emissions during rainfall. Therefore this research was performed to determine the pollutant EMC and to suggest the possible best management practice for treating nonpoint pollutants from a railway station. The $95\%$ confidence intervals of pollutant EMC were ranged to 69.4-115.2mg/L for TSS, 132.7-190.4mg/L for COD, 5.4-15.1ug/L for Oil & Grease, 4.9-12.4mg/L for TKN and 568.4-620.1ug/L for TP. The first flush criteria was ranged to 5-10mm accumulated rainfall using dynamic EMCs, Also laboratory reactor testing was performed. It shows that Zeolite media is useful for removing the washed-off pollutants from a railway station, especially for metal ions.

• Tribology and Lubricants
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• v.24 no.4
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• pp.179-185
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• 2008

Microporous polymer lubricants(MPLs) are solid polymer materials containing micropores which are filled with liquid lubricants, and which are molded or formed to suit rolling bearings or other machine parts requiring lubrication. MPLs can be effectively applied to provide long-term, maintenance-free lubrication of a variety of machine elements without fully replacing of oils and greases. The application of rolling bearings packed fully with an MPL could reduce or eliminate the problems such as grease deterioration, leakage, under-lubrication caused by insertion of water or foreign matters under severe operation conditions. This paper discuss the application of MPLs for lubrication of rolling ball bearings. Two different MPLs were synthesized and the features of MPLs were tested. Characteristics of the bearings which are packed fully with synthesized MPLs were investigated using SEM, TG/DSC, extents of oil leakage, OIT, and life time test. After these preliminary tests twelve MPLs were synthesized and evaluated by measuring extents of oil leakage and OIT values. Then synthesis conditions for the optimum MPL were selected by SSRED(Six Sigma Robust Engineering Design) pro gram using extents of oil leakage and OIT values respectively. The optimum MPL by means of OIT value showed higher performance such as long life time and application at higher temperature of $140^{\circ}C$ than previous temperature of $100^{\circ}C$.

• Transactions of the Korean Society of Automotive Engineers
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• v.18 no.6
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• pp.84-90
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• 2010

This paper presents the shape optimization process for the automotive wheel bearing seal lip using the finite element method and the response surface method. First, to predict performance of the bearing seal lip, we used the non-linear finite element analysis. And then, we compared the analysis results with the test results to verify the finite element model. The objective function in optimizing process was obtained from results of the mud slurry test, which is one of many tests for evaluating performance of wheel bearing. After the mud slurry test for the four models which have the similar cross-sectional shape, we measured the wear area of the seal lip and the moisture content in grease. The objective function has been chosen by comparing the results of mud slurry test and characteristics of seal lip, such as contact force, contact area, contact pressure, and interference. Finally, within limited design parameters, we suggested the optimized shape of seal lip, which is expected to improve the wear and the sealing effect of it.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.24 no.4
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• pp.149-155
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• 2010

This paper was carried out to estimate pollution levels of various insulators in tunnel and establish cleaning period in each tunnel section. We estimate pollution level that is attached to insulators in environmental pollution area, industrial area, salt damage area. These results that the pollution quantity and conductivity were increased by pollution accumulation period. However, the conductivity showed each other big difference in each tunnel. In particular, the conductivity showed big in environmental pollution(tunnel A) and salt damage(tunnel C) area, It is considered to prevent accident that manage establishing periodic state of cleaning plan. Also, the Grease that spread on the insulator surface in existing is considered that it can prevent accident for long-term by restrain use.

• Tribology and Lubricants
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• v.29 no.6
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• pp.397-402
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• 2013

This study examined the tribological characteristics of the drive shaft and axle system in vehicles. The first drive shaft example contained end play for a CV joint that transferred part of the transmission power to the wheel. The joint part of the drive shaft was deformed because of reduced durability due to wear. Thus, vibrations caused the body to shake and become unbalanced when the drive shaft transferred the power. The second example was the cross-section of a shaft that connected the slip-connection of the propeller shaft on the input side to the yoke flange of the output side; the durability was reduced because of corrosion. End play caused by wear between the bearing and cross-section shaft appeared to cause shaking. In the third example, a grease leak reduced lubrication and thus caused damage to the hub bearing and inside the knuckle. The failure was produced by sticking. The fourth example had noise produced by the gear and gear transfer. This was due to the backlash of the pinion and few ring gears for the differential gear. Therefore, drive shaft and axle systems must be thoroughly checked and managed to minimize and reduce failure phenomena.

• Journal of Electrochemical Science and Technology
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• v.2 no.2
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• pp.85-90
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• 2011

Active oxygen species or free radicals are considered to cause extensive oxidative damage to biological macromolecules, which brings about a variety of diseases as well as aging. Electrolyzed reduced water(ERW) has been regarded as a ideal antioxidative agent in recent years. ERW is produced by passing a diluted salt solution through an electrolytic cell, within which the anode and cathode are separated by membrane. It can be produced reactive materials in ERW near the cathode during the electrolysis of water. ERW have the following advantages over other traditional cleaning agents: effective antioxidative agent, easy preparation, inexpensive, and environmentally friendly. The main advantage of ERW is its safety and antioxidative effect. ERW with strong reducing potential can be used to remove dirt and grease from items such as cutting boards and other kitchen utensils. The primary aim of this study is the activation mechanism of oxidation reduction potentials, ion conductivity, pH, and electrochemical properties with reactive materials in ERW.

• Journal of Applied Tourism Food and Beverage Management and Research
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• v.10
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• pp.219-238
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• 1999

Obestity, characterized by an excess accumulation of fat, is a detriment to good health and wellbeing. It is easy for individuals to take on excess fat as soon as enough food and leisure are available in a society, causing an imbalance between energy intake and energy expenditure. Although there has been disagreement as to which side of this energy equation is more important in th epidemic of obesity, both sides are certainly involved. I think the prevalence of obesity begins with infancy. It seems to be relatively constant throughout childhood. Some retrospective studies have suggested that there is a direct progression from a fat chile to a fat adult. Obesity has been associated with excess mortality in many studies. The effect of obesity on cardiovascular disease has not always been an independent one, but has generally been through exacerbation of other rish factors such as hypertention, diabetes, hyperlipedmia, galbladder disease, gout and cancer of the grease and endometrium. The weights of identical twins raised in separate homes have been reported to be similar, thereby suggesting that heredity contributes significantly to weight. Overweight and obesity are by far greater health problems for many people in our society. Therefore in this paper we consider the relationship between body energy balance and problems of obesity. Whatever the weight of the person, the goal of the nutritionist and health care workers is to find solutions that will allow persons to feel better about themselves.

• Journal of the Korean Society for Precision Engineering
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• v.30 no.9
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• pp.943-950
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• 2013

This paper describes the thermal contact resistance and its effect on the performance of thermal interface material. An ASTM D 5470 based apparatus is used to measure the thermal interface resistance. Bulk thermal conductivity of different interface material is measured and compared with manufacturers' data. Also, the effect of grease void in the contact surface is investigated using the same apparatus. The flat type thermal interface tester is proposed and compared with conventional one to consider the effect of lateral heat flow. The results show that bulk thermal conductivity alone is not the basis to select the interface material because high bulk thermal conductivity interface material can have high thermal contact resistance, and that the center voiding affects the thermal interface resistance seriously. On the aspect of heat flow direction, thermal impedance of the lateral heat flow shows higher than that of the longitudinal heat flow by sixteen percent.