• 설비공학논문집
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• 제15권12호
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• pp.1007-1017
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• 2003

An experimental study on the air-side pressure drop and heat transfer coefficient of slit fin-tube heat exchanger has been carried out. The data reduction methodology for air-side heat transfer coefficients in the literature is not based on a consistent approach. This paper focuses on new method of data reduction to obtain the air-side performance of fin-tube heat exchanger using R22 and recommends standard procedures for dry and wet surface heat transfer estimation in fin-tube heat exchanger having refrigerant on the tube-side. Results are presented as plots of friction f-factor and Colburn j -factor against Reynolds number based on the fin collar outside diameter and compared with previous studies. The data covers a range of refrigerant mass fluxes of 150∼250 kg/$m^2$s with air flows at velocity ranges from 0.3 m/s to 0.8 m/s.

• 대한치과의사협회지
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• 제10권3호
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• pp.149-153
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• 1972

The apical foramen is not always found on the very tip of the root. The apical foramen may make its exit on the mesial, distal, labial or lingual side of a root slightly short of the root apex rather than at the root apex itself. The author collected 43 upper first molars and 84 lower first molars as a samples. Apical foramens were carefully checked and examined these location on each tip. (table 1) 1. About 33% to 49% of upper cases were found on extreme tip of roots and the remaining cases were on the distal side or mesial side. 2. Except distal simple canal of lower molars, approximately 40% to 50% were located on the very tip of the root. The remaining cases were on distal or mesial surface. 3. On lower distal simple canal, about 51% of cases made its exit on distal side. The remaining cases located on the tip end or mesial side.

• 대한치과의사협회지
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• 제12권2호
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• pp.123-129
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• 1974

The electrical activities of masseter muscle were recorded on 9 subjects with unilateral fracture of mandible. The electromyographic studies were executed with 2 channel RS dynograph recorder for electromyography. The graphs were recorded in the physiologic rest position, incisal occlusion, molar occlusion, left lateral excursion, right lateral excursion, and protraction. The following conclusions were drawn; 1. In the physiologic rest position, incisal occlusion, molar occlusion, and protraction, the electrical potentials of the masseter muscle were greater in the affected side. 2. In the right lateral excursion, the electrical potentials of the masseter muscle were greater in the right side, and in the left lateral excursion, greather in the left side. There is no correlation mutually between the affected side and unaffected side.

• 대한치과보철학회지
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• 제22권1호
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• pp.17-22
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• 1984

A clinical evaluation was made on teeth in 113 subjects from ages 19 to 23 with Angle's Class I occlusion who were free from prosthesis, orthodontics, and occlusal equilibration. The study was made to determine if there was a relation between the type of occlusion, non-working contact and temporomandibular dysfunction. From the foregoing study, the author obtained the following results. 1. In lateral excursion, there was not any significant difference between bilateral canine protected occlusion (31%), bilateral group function (32.7%), and mixed type (34.5%). 2. Only 10 of 113 subjects studied had non-working side tooth contacts (8.2 per cent). 3. Twenty per cent of subjects with non-working side contact showed temporomandibular joint dysfunction. 4. Non-working side contacts were not observed in subjects with canine guided occlusion. 5. It would be premature to relate the type of occlusion on working side directly to temporomandibular joint dysfunction.

• 한국기계가공학회지
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• 제8권2호
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• pp.40-45
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• 2009

This study is analyzed by stress contour of automotive tire at contact on road surface. Maximum equivalent stress as 61200Pa is shown on the lower mid part in case of tire contacted on road surface. As the air pressure of tire increases, maximum total deformation as 5mm is shown on the side part of tire. It can be shown that the side part of tire is unstabilized. There is no load effect on tire at its upper and lower directions. When the moment applied on the side of tire is increased 1.4 times as its value, the value of maximum principal stress is increased 1.4 times. The stress at the tire is in proportion to the moment applied on the its side. The tire tends to incline toward its side by this moment.

• 한국생산제조학회지
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• 제22권3호
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• pp.437-446
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• 2013

There have been numerous studies on end milling processes. However, these have been restricted to the application of tools for special cutting purposes. A side milling cutter can handle long, deep, and open slots in a more efficient manner, and it provides the best stability and productivity for this type of milling. In this paper, a method to predict the cutting forces in side milling is described, and simulated cutting forces are compared with those obtained by cutting experiments. In particular, the side milling process easily generates relative motion between the tools and the workpiece because it produces intermittent cutting forces that cause vibrations over a wide frequency range. Therefore, the application of a dynamic cutting model instead of a static cutting model is appropriate to forecast the cutting forces more accurately.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2008년도 춘계학술대회 논문집
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• pp.270-273
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• 2008

The integrated power system combining a tidal power plant and two ocean current power parks is suggested. It is characterized by the set up of an ocean current power park in the lake side by installing a number of ocean current turbines generating electricity by using sea water flow discharged into the lake side from the turbine generator of a tidal power plant and an ocean current power park in the sea side by installing a number of ocean current turbines generating electricity by using sea water flow exiting into the sea side through the sluice gate from the lake side. The vision of the integrated power system is demonstrated by the simple theory and simulation results of the SIWHA Tidal Power Plant. And it is shown that the newly proposed integrated power system combining tidal power and ocean current power can produce very high economical benefits.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2003년도 추계학술대회 논문요약집
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• pp.16-16
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• 2003

In this study, for a safety assessment of wheelchair occupant in side impact, we used a dynamic sled impact test results. The test was carried out total 6 times and impact speed was 13g$\pm$0.43/28km/h$\pm$0.95, By using EURO SID-1 dummy, head performance criteria(HPC), abdominal peak force, etc. were measured. We evaluated wheelchair occupant safety by motion criteria(MC) which was measured by head, trunk and side deformation change of wheelchair and Head & Neck injury criteria(HNI) measured by using head and neck deformation angle and time relation. When we assumed that the maximum injury value in side impact was 100%, the results of motion criteria(MC) of wheelchair occupant were max 80.3, mim 32.3 and average 60.3%, Head & Neck injury criteria(HNI) value were max 118.4, min 14.5 and average 59.7%.

• 대한정형도수물리치료학회지
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• 제1권1호
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• pp.99-104
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• 1995

Markolf and Morris suggests that the deranged disk and torn annulus have an exellent recovery ability from the position of spine extension, where the posterior annulus is not under stress and the gel can move anterioly. McKenzie explains side gliding as a combination of rotation and side bending, his clinical studies indicate that side-gliding can gel laterally. In conclusion, the prone unilateral traction on the opposite side from the patient's pain along with the other treatment appered to have helped reduce those patient's pain. The method of treatment described in this report is suggested for Korean physical therapists who treat patients suspected of posterolateral herniated nucleus pulposus.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2004년도 추계학술대회 논문집
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• pp.1487-1490
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• 2004

In this study, the crash analysis was carried out to evaluate the influence of steel sheet grade and thickness on weight reduction and crash characteristics for front side member which had an important role of absorbing the impact energy during front and side impact. In order to achieve the aim of this study the reverse engineering was applied to obtain 3D model of front side member from BIW for the FE simulation. In the result, the crashworthiness of front side member is considerably improved with steel sheet strength and thickness increase. Also, the weight reduction in automotive parts for the improvement of the fuel efficiency can be easily achieved with applying high strength steel without deterioration of crashworthiness.