• 한국정밀공학회:학술대회논문집
• /
• 한국정밀공학회 1995년도 추계학술대회 논문집
• /
• pp.3-7
• /
• 1995

Force generated during grinding process causes elastic defomation. The effect of this deforms a workpiecs. So grinding system is explainable using the concept of macining elasticity phenomenon. Machining elasticity is defined as ratio between the true depth of c ut, and an importnat factor to affect material removal mchanism and productivity. Generally, to produce accurate surface and dimensionally precise components operators depend on their experiences. Because of these, productivity is reduced and time is wasted. The objective of this reserch is to study the effect of grinding conditions, such as table speed, depth of cut on the machining elasticity parameter.

• 한국지반공학회:학술대회논문집
• /
• 한국지반공학회 2005년도 춘계 학술발표회 논문집
• /
• pp.956-965
• /
• 2005

In this paper, the effect on the forced replacement depth of the revetment in soft soil with inter sand layer is analyzed by model test. In the result, the forced replacement occur in 60 second from filling the embankment material. The shape of the forced replacement depth is like to punching shape. Then, in case of thin inter sand layer and near the embankment, the forced replacement depth of inter sand layer case is more than only clayed soil case.

• 비파괴검사학회지
• /
• 제4권2호
• /
• pp.7-14
• /
• 1985

An experiment to investigate the rate of change of phase angle of eddy current output signal caused by outer surface defect of nonferromagnetic tube by variation of standard depth of penetration and variation of percent of tube wall penetration was carried out. The results of the experiment show that the phase angle of defect signal is increased with decreasing the standard depth of penetration or the depth of defect. The results also show that the phase angle is decreased with increasing the skin effect of eddy current, and that the resolution is decreased with decreasing the depth of defect.

• 한국지반공학회논문집
• /
• 제20권9호
• /
• pp.145-153
• /
• 2004

본 연구에서는 기존에 제안된 각 연구자들의 치환심도 산정식을 고찰하고, 이를 토대로 영향인자를 고려한 수정식을 제안하였으며, 제안된 수정식을 국내 대표적인 강제치환 시공 사례지역인 남해안 광양만일대(여천, 율촌, 광양)의 시공사례에 적용하여 국내지반에서의 적용성을 조사하여 보았다. 또한 지반조사 결과를 바탕으로 산정된 수정성토하중과 극한지지력의 관계로부터 수정지지력계수를 결정하였으며, 결정된 수정지지력계수를 적용하여 치환심도를 예측하였다. 그리고 율촌, 여천지역의 시공시 각 영향인자별 상관성 분석을 통한 상호관계를 유도함으로서 인접지역 또는 유사지 역에서 치환심도를 예측할 수 있는 경험적 인 치환심도 예측기법을 제안하였고, 제안된 경험식을 광양지 역에 적용한 결과 예측결과는 실제 치환심도와 매우 근사한 결과를 나타내었다.

• Journal of Welding and Joining
• /
• 제34권3호
• /
• pp.17-22
• /
• 2016

In terms of mechanical and metallurgical characteristics, the effect of tool plunge depths(0.2, 0.5, 0.7, 1.0, 1.5mm) on weldability in dissimilar Al5083-O/DP590 friction spot joint has been clarified. From the results, it is found that the stirred nugget was stably formed at a plunge depth of more than 0.7mm, which is caused by improved stirring action against each other material. With increasing a plunge depth, the thickness of intermetallic compound(IMC) layer in Al5083-O/DP590 joint has a tendency to increase. The tensile shear strength reaches to the maximum failure load of 6.5kN at a plunge depth of 0.7mm due to relatively small decrease in the thickness of Al5083-O sheet and relatively minute thickness of IMC layer, compared with those of other plunge depth conditions.

• 대한치과의사협회지
• /
• 제55권1호
• /
• pp.22-29
• /
• 2017

Purpose : Preservation of the periodontal health of the treated patient requires supportive periodontal therapy for the elimination of periodontal disease. After Phase I therapy is completed, patients are placed on a schedule of periodic recall visits for maintenance care to prevent recurrence of the disease. The amount of tooth loss would be the most relevant criterion in an evaluation of the effect of periodontal treatment, but this would require studies with extremely long follow-up periods. Thus the most commonly used outcome criteria in clinical research have been clinical attachment level change, reduction of pocket depth and bleeding frequency. The purpose of this case study is to identify the effect of supportive periodontal therapy after periodontal flap surgery. Materials & Methods : Following routine hygienic phase of treatment, patients with chronic periodontitis received surgical periodontal treatment. Bleeding on probing, pocket depth and clinical attachment level were measured at baseline, pre-operation and 1 year follow up. All procedures were performed by one operator. Results : One year a total of 28 patients (58sites) to recheck remained, when conducted maintenance program after periodontal flap surgery was observed reduction of bleeding frequency, pocket depth and improvement of clinical attachment level. Conclusion : The results from this study indicate that supportive periodontal therapy after periodontal flap surgery is effective for reduction of bleeding frequency, pocket depth and gain of clinical attachment level.

• 대한조선학회지
• /
• 제13권1호
• /
• pp.11-16
• /
• 1976

The effect of the bow shape on the ship motion response in longitudinal regular waves of water of finite depth is investigated by employing the strip theory. The two-dimensional hydrodynamic forces(added mass and damping) were calculated by close-fit method for water of finite depth. The models for investigation are U and V bow ship forms of block coefficient 0.8 with constant after body which were used by Yourkov [2] and recently by Kim [3] for their deep water investigations. The following results are obtained by the present numerical experiments. (1) It is confirmed that the damping coefficient of the V-bow ship is greater than that of U-bow ship and in consquence the amplitude of heave and pitch of V-bow ship is smaller than that of U-bow ship among longitudinal regular head waves in water of finite depth (2) The merit of the V-bow ship on the motion damping is more significant in heave than in pitch, and is decreasing with the shallowness of water depth. (3) The change of bow form gives little effect on the wave exciting force and moment compared with the motion responce.

• Medical Lasers
• /
• 제10권3호
• /
• pp.146-152
• /
• 2021

Background and Objectives Although lasers have been widely applied in tissue treatment, the light penetration depth in tissues is limited by the tissue turbidity and affected by its absorption and scattering characteristics. This study investigated the effect of using an optical clearing agent (OCA) on tissue to improve the therapeutic effect of 1064 nm wavelength laser light by reducing the heat generated on the skin surface and increasing the penetration depth. Materials and Methods A diode laser (λ = 1064 nm) was applied to a porcine specimen with and without OCA to investigate the penetration depth of the laser light and temperature distribution. A numerical simulation using the finite element method was performed to investigate the temperature distribution of the specimen compared to ex-vivo experiments using a thermocouple and double-integrating sphere to measure the temperature profile and optical properties of the tissue, respectively. Results Simulation results showed a decrease in tissue surface temperature with increased penetration depth when the OCA was applied. Furthermore, both absorption and scattering coefficients decreased with the application of OCA. In ex-vivo experiments, temperatures decreased for the tissue surface and the fat layer with the OCA, but not for the muscle layer. Conclusion The use of an OCA may be helpful for reducing surface heat generation and enhance the light penetration depth in various near-infrared laser treatments.

• 재무관리연구
• /
• 제26권4호
• /
• pp.141-163
• /
• 2009

Using the extensive datasets, I analyze the effect of tick size changes on the intraday patterns of spread and depth. I show that intraday variations in spread (depth) are greater (smaller) with smaller tick size during the early hour of trading and become smaller (larger) during the last hour of trading. And the standardized spreads (depths) are quoted at the lower (higher) levels as the tick size becomes smaller. I also find that U-shaped intraday spread pattern changes to the reverse flat S-shape while inverted U-shaped depth pattern does to the flat S-shape.

• 대한조선학회지
• /
• 제12권2호
• /
• pp.59-66
• /
• 1975

Recently, as the dimensions of energy carriers increase, especially in draft, a reliable prediction of the ship motions at finite depths of water becomes necessary. The purpose of this paper is to probe the effect of finite water depth on the hydrodynamic forces and ship motions, particularly heave and pitch, in longitudinal regular head waves, by comparing the experimental value of Freakes and Keay with the author's theoretical value obtained by applying the modified strip theory to the Mariner class ship. It is confirmed that generally the hydrodynamic coefficients in the equations of motion increase with decreasing water depth, and the wave exciting forces and moments decrease with decreasing water depth. Amplitudes of heave and pitch in longitudinal regular head waves decrease as the water depth in the range where the length of the incident wave is comparatively long. The effects of Froude Number on the hydrodynamic coefficients increase with decreasing water depth and is more noticeable in the case of heave than pitch. In heave, generally the discrepancy between the experimental value and the theoretical value is relatively small in the case of $F_n=O$, but it is very large in the case of $F_n=0.2$. It is considered that the trend stems from the ignorance of the three dimensional effect and the other effects due to shallowness of water on the hydrodynamic coefficients in the theoretical calculation. An extension of methods for calculating the two dimensional hydrodynamic forces to included the effect of forward speed should be recommended. It is required that more experimental works in finite water depths will be carried out for correlation studies between the theoretical calculation, according tp modified strip theory, and model experiments.