• 한국안전학회지
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• 제19권1호
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• pp.12-17
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• 2004

By using an experimental approach recently developed to determine the torque-tension relationship for bearing frictional characteristics of several typical bolted joints were studied. The experimental approach allows the direct determination of the bearing friction between the nut and its bearing surface. Detailed friction studies were made on the influences of the size and shape of the hole, the use of a slot in a bolted joint, contact area and position, and other factors such as turning speed, coating, and the use of wax on the bearing surface. The contact area and position of the washer have a marginal effect on the bearing friction. The organic coating on the nuts reduces the bearing friction significantly. Nuts with organic coating over a washer with zinc finish provide the smallest and the most consistent bearing friction. The results from the experimental investigation will be helpful for the better design of bolted joints bearing friction. The results from the experimental investigation Will be helpful for the better design of bolted joints.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2001년도 봄 학술발표회 논문집
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• pp.299-306
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• 2001

Crushed Stone Pile(CSP) is one of the ground improvement methods available to loose sand and clayey ground by forming compacted CSP in the weak soil layer. The effects of this method are enhancement of ground bearing capacity, reduction of settlement and prevention of lateral ground movement in cohesive layer, reduction of liquefaction potential in sandy ground. This study performs model tests in 1.0m${\times}$1.0m${\times}$1.0m and 1.5m${\times}$1.5m${\times}$l.2m model tank to observe bearing capacity of CSP treated ground. The area replacement ratio of CSP composite ground varies 20%, 30% and 40% with square grid pattern. After the composite ground was consolidated under pressure of 0.5kg/$\textrm{cm}^2$ and 1.0kg/$\textrm{cm}^2$, load tests were carried out. The results show that ultimate bearing capacity increases with area replacement ratio and the preconsolidation pressure of ground.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2010년도 춘계 학술논문 발표대회 1부
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• pp.25-27
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• 2010

Helical steel piles are being widely used in foundation for the buildings in urban areas because of their high compressive and tensile capacities. Helical steel piles have many advantages; ease installation, a vibration-free and low level of noise process, and so on. However, the most researches are about the capacity of helical steel piles under uplift condition. Therefore, this paper focuses on the capacity under compressive loading according to the soil condition. The bearing capacity of helical steel piles varies with the diameter of the helix and shaft and the bearing area of helical steel piles is not always identical with the sum of helix and shaft area due to the difference of each bearing mechanism. Therefore, the experiment with the parameters of the ratio of helix and shaft diameter and soil condition will be carried out to survey the effective helix area under a given soil condition for the bearing capacity of helical steel piles.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2009년도 세계 도시지반공학 심포지엄
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• pp.1001-1010
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• 2009

The study that unconfined compression strength of intact rock which is the most important factor to determine the bearing capacity effects discontinuities in rock mass has been carried out actively so far. However, the study which is related to lithological characters such as vesicle which is one of the primary characteristics of Basalt has barely been conducted. On this study, We have analyzed the correlation-ship between vesicle and unconfined compression strength and the effect on the bearing capacity, based on the reviewing on the changes of unconfined compression strength as the amount of vesicle of Basalt. It is impossible to analyze the amount of vesicle of Basalt as measuring unit. So it was analyzed by the ratio of the core sample's surface area and another area that vesicle takes up. Also, unconfined compression strength was calculated by point load test and unconfined compression strength test. The analysis shows that vesicle area ratio and unconfined compression strength have the exponential relationship and vesicle area ration is the factor to determine the bearing capacity of Basalt. It is considered that the reliability of calculating of the bearing capacity of Basalt will be improved as we study the correlation-ship between the vesicle area ratio and rock mass grade hereafter.

• 한국공작기계학회:학술대회논문집
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• 한국공작기계학회 2004년도 추계학술대회 논문집
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• pp.480-484
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• 2004

Despite is product that existent higher hrust engine, ship, vehicles, development equipment and Metal Bearing for plant equipment Cast White Metal Lining Bearing that is Bimetal Bearing standing 2 generation is accomplishing master and servant and this is foreseen to be used widely on industry whole in hereafter but Cast White Metal Bearing need minuteness processing, price competitive power is depending on income from superior another thing area than itself manufacture already in advanced nation to lowdown that the technique is generalized widely.

• 한국방재학회 논문집
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• 제5권4호
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• pp.37-47
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• 2005

본 연구는 화강 풍화암반의 지지력 및 침하특성을 평가할 목적으로 수행된 것으로 흡수율에 따라 풍화도를 고찰하고 원위치 심도에서 평판재하시험을 수행하여 이를 기존의 예측방법 및 공내재하시험 결과와 비교, 검토하였다. 이를 위하여 국내의 대표적인 화강 풍화암 분포 지역인 경기 $\bigcirc\;\bigcirc$지역을 시험 부지로 선정하였으며 그 시험 결과에 의하면 평판재하시험시 풍화도가 증가할수록 지지력은 지수적으로 감소하고 특정 풍화도를 경계로 지지력 감소폭이 크게 증가하는 것으로 확인되었다. 또한, 기 제안된 지지력 공식을 이용하여 화강 풍화암반의 지지력을 추정한 결과 풍화도가 증가할수록 평판재하시험 결과와 유사한 경향을 보이는 것으로 나타났다. 한편, 평판재하시험이 수행된 동일 위치에서 실시된 공내재하시험 결과 지지력은 비교적 평판재하시험과 유사한 경향을 보이고 있는 것으로 나타났다.

• 자원환경지질
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• 제13권4호
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• pp.241-246
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• 1980

Some components in uranium-bearing formations which consist mainly of black shale, slate. and low grade coal-bearing formation of Ogcheon Belt were processed statistically in order to find out the geochemical correlations with uranium. Geochemical enrichment of uranium, vanadium and molybdenum in low grade coal-bearing formations and surrounding rocks is remarkable in the studied area. Geochemical correlation coefficient of uranium and molybdenum in the rocks displays about 0.6, and that of uranium and fixed carbon about 0.4. Uranium and vanadium in uranium-bearing low grade coals denote very high correlation with fixed carbon, which is considered to be responsible for enrichment of metallic elements, especially molybdenum. Close geochemical correlation of uranium-molybdenum couple in the rocks can be applied as a competent exploration guide to low grade uranium deposits of this area.

• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 2010년 춘계학술대회논문집
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• pp.258-262
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• 2010

Since MEMS based micro actuators or generating devices showed high efficiency per volume, plenty of research are ongoing. Among them, MEMS based millimeter-scale micro gas turbine is one of the most powerful item for replacing chemical batteries. However, due to MEMS manufacturing technique, it is very difficult that makes wide turbine bearing area. It causes low DN number, so sufficient bearing force is hard to achieve. Thus, the most important issue on micro gas turbine is to design the proper bearing which can keep rotor stable during operation. In order to that, micro-scale gas-lubricated bearing is generally used. In this paper, basic feasibility study of thrust bearing of 10mm diameter turbine is described. Thrust bearing is hydrostatic gas-lubricated type. Numerical simulation is performed with ANSYS CFX 11.0 which is commercial numerical tool. Relationship between bearing inlet pressure and mass flow rate and bearing force is figured while changing bearing gap and number of capillaries. The simulation results will be used for further design of micro gas turbine.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2008년도 추계 학술발표회
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• pp.691-699
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• 2008

In the design of a foundation, settlement of the foundation may exceed allowable design criteria even with a competent bearing stratum. In such a case, a piled-raft foundation system may be adopted using piles as settlement reducing component. In this paper, Disconnected Piled Raft Foundation (DPRF) system, which installs disconnected piles underneath the raft and uses the piles as ground reinforcements, is studied as a cost effective design method against the classical piled-raft foundation system. To this end, large size loading tests were carried out on weathered ground changing area replacement ratio and length of piles. The results indicated that the settlement of the reinforced ground was reduced by 34~87% and the allowable bearing pressure increased by 70% on average from those of the unreinforced original ground, respectively. The correlating formula between the area replacement ratio and the load bearing ratio of piles were derived from the test results and numerical analysis. From the correlation, a design method determining the size and the quantity of the disconnected piles to enhance the bearing capacity of original ground to the desired value was proposed based on one inch settlement criteria.

• The Journal of Korean Physical Therapy
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• 제21권2호
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• pp.23-29
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• 2009

Purpose: This study examined the effects of the symmetrical scapular alignment on the weight bearing of hemiplegic patients in the standing position. Methods: PALM (PALpation Meter) test and Gaitview AFA-50 were used to measure the skeletal alignment of the scapula and the weight bearing loaded on the affected and unaffected sides before and after training. The data was analyzed using a paired t-test on the SPSS 12.0 program for descriptive statistics. A p value <0.05 was considered significant. Results: The mean difference in the scapular alignments on sup. & mid. & inf. area in the hemiplegic side before and after training was $0.93\pm0.50cm$ and $0.58\pm0.43cm$, respectively. There was a significant decrease after training rather than that before (p<0.05). The mean weight bearing on the foot area in the hemiplegic patients before and after training was $9.12\pm5.51N/cm^2$ and $4.36\pm4.11N/cm^2$, respectively,. There was a significant decrease after training rather than that before (p<0.05). The scapuar alignments and weight bearing data on the standing position were grouped around the average (to central point) in the distribution graph. Conclusion: These findings suggest that the symmetrical scapular alignment can serve as an effective means of improving the weight bearing ability of hemiplegic patients.