• Journal of Oral Medicine and Pain
• /
• v.17 no.1
• /
• pp.89-94
• /
• 1992

To evaluate Helhimo's Anamnestic Dysfunction Index(AI), Helkimo's Clinical Dysfunction Index(HDI), and Friction's Craniomandibular Index(CMI) in Korean Young population, clinical examinations were performed in 207 dental college students who were healthy and had no evidence of the craniomandibular disorders. The obtained results were as follows; 1. The mean values of the Helkimo's Anamnestic Index(AI), Clinical Dysfunction Index(HDI), Fricton's Palpation Index(PI), Dysfunction Index(DI), and Craniomandibular Index(CMI) were 0.35, 0.71, 0.03, 0.05, and 0.04 in male subjects. 2. The mean values of the Helkimo's Anamnestic Index(AI), Clinical Dysfunction Index(HDI), Fricton's Palpation Index(PT), Dysfunction Index(DI), and Fricton's Craniomandibular Index(CMI) were 0.42, 0.72, 0.02, 0.04, and 0.03 in female subjects. 3. There was no statistically significant difference between male and female subjects in each parameter. 4. The palpation index(PI) observed in Korean Young Population was lower than that in American population.

• Proceedings of the KWS Conference
• /
• 2000.10a
• /
• pp.308-310
• /
• 2000

• Proceedings of the Korean Geotechical Society Conference
• /
• 2010.03a
• /
• pp.1104-1113
• /
• 2010

In order to reduce negative skin friction uses bitumen most plentifully. But, Bitumen is expensive very of 1.5 or more times of pile material expense. The bitumen will be able to substitute it is nescessary. It was researched that it would be able to bitumen substitutions from in products which is produced from domestic in this study. This was composed with most bentonite, added some cement. When it is used this product in the model test, the reduction ratio appear of 85% or more. In this result, this product as the reduction material is confirmed that has enough ability. Additional research leads, the product according to pile construction method must verify the reduction effect of negativ skin friction in field test.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
• /
• 1996.04b
• /
• pp.145-152
• /
• 1996

This paper deals with an experimental study on the f~iction torque characteristics of magnctic fluid seals for various oil temperatures, rotating speeds, and vacuum pressures. The friction torque of MFS was measured by high response torque meter. The experimental results show that, as the rotating speed increases, the fi'iction torque of MFS increases and as the oil temperature increases, the friction torque of MFS decreases. Also, the experimental results show that the friction torque of Model II is 1.73 ~ 2.56, 2.0 ~ 2.89, 2.0 - 3.25 times larger than those of Model I under the atmospheric pressure, vacuum pressure(10$^{-4}$ and 10$^{-6}$ torr), respectively.

• Journal of KSNVE
• /
• v.9 no.2
• /
• pp.387-392
• /
• 1999

This paper presents design guidelines for the automatic ball balancer in CD/DVD systems with varying eccentricity. In these systems, the size of balancing balls should be limited by the restricted race space so that determination of the number and mass of balls should consider the radii of the race and the balls. In addition, the effects of viscosity and friction also should be taken into account for sufficient balancing. Based on the static equilibrium conditions, the number and mass of balls corresponding to the range of varying eccentricity have been determined. Dynamic simulation with viscosity and friction shows sufficient viscosity must exist to ensure stability and friction between balls and race must be minimized to guarantee accurate balancing.

• Journal of the Korean Geosynthetics Society
• /
• v.2 no.1
• /
• pp.3-13
• /
• 2003

Recently, construction of the reinforced earth structures, which adopts reinforcing materials of geosynthetic, is rapidly increasing due to its good economic advantages, beautiful appearance, and convenient construction. Nonetheless, the most important factor of interpretation and design of the reinforced earth structures, which is assessment ways of friction features between earth and geosynthetic, has not been standardized yet. It has great difference of interpretation and design methods which suggested to the design engineer. This study is to present the way how to assess more reasonably friction features between geogrid and weathered granite soil through the pullout test. Based on a large-scale pullout test of geogrid, the maximum shear stress, interface fricton angle, and friction efficiency are presented with consideration of various test condition.

• Journal of Oral Medicine and Pain
• /
• v.19 no.1
• /
• pp.93-103
• /
• 1994

In order to evaluate thelong-term results of conservative treatment on TMJ closed lock, a follow-up study of thirst-two patients was performed 2 to 7 year after treatment. Evaluating method included the questionnaire, clinical examination, transcranial radiograph and mandibular kinesiography. The results were as follows : Seventy-eight percents of patients reported that symptoms were reduced completely or considerably. Recurrent headache was improved after treatment (72 percents of success rate). There was a significant decrease in VAS after treatment and at follow-up comparing with that of before treatment(p<0.01). Most common variable of Helkimo's clinical dysfunction index at follow-up was impared TMJ function. There was a significant decrease in Fricton's craniomandibular index and dysfunction index(p<0.01) Mean interincisal distance was increased by 14.07mm after treatment and was also increased at follow-up by 2.80mm comparing with that of after treatment(p<0.01). Before treatment, condylar translation measurements of affected and non-affected sides on the transcranial radiograph were 4.89±3.20mm and 9.09±3.73mm respectively and at follow- up examination, those were 14.98±4.77 and 17.05±4.35mm respectively. At follow-up, condylar translation were increased significantly comparing with those of before treatment(p<0.01). In 93.1% of patients, the condylar position of affected side at maximum mouth opening was behind the articular eminence before treatment but the percentage was decreased to 13.8% at follow-up(p<0.01). The pattern and range of mandibular movements at follow-up examination were similar to the typical normal movements. And in 16 cases showing lateral deviation of opening path, the deviation was directed to the affected and non-affected sides with the same frequency.