• 대한치주과학회:학술대회논문집
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• 1997.11a
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• pp.8-8
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• 1997

• Transactions of the Korean Society of Automotive Engineers
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• v.18 no.1
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• pp.58-65
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• 2010

For the improvement of fuel consumption, the study on the use of lightweight material or thinner sheet have been carried out in automotive industry. With the need for the use of thinner sheet, the dent resistance became one of the major concern in th design of exterior panels in automotive industry. Many studies have been carried out for the dent resistance by experiment or quasi-static numerical simulation. In this study, the dent formation behavior is investigated by dynamic finite element analysis using ABAQUS. Dent formation may be affected by many factors such as sheet thickness, material properties, pre-strain, and sheet curvature. The effect of these factors on dent resistance is investigated. From the analysis following three conclusions are derived. First, dent resistance become hard as the sheet curvature radius increases. Second, dynamic dent resistance is mainly affected by bending stress rather than tensile stress. Third, the pre-strain itself do not give any guidance for dynamic dent resistance and dynamic dent resistance have to be decided considering the strain hardening and thickness reduction together. The results are considered to be reliable and useful to improve the dent damage of automotive panels.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 2003.11a
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• pp.395-401
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• 2003

In this paper, the dent printing phenomena and critical dent size which lead to premature failure of deep grooved ball bearing for automobiles are presented. The results of newly assembled test bearings showed that the ball dent size strongly affect the bearing life and inner ring raceways were the major failed parts in spite of using the dented balls. The dent printing phenomena are a root cause of premature failure, which was not reported until now. And there exist the critical ball dent size for given rolling bearings and operating conditions. So, the initial condition of tribologically mating parts should be treated as important as the failed body itself.

• Journal of The Korean Society of Grassland and Forage Science
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• v.6 no.1
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• pp.14-18
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• 1986

This experiment was conducted to study yield and nutritive value of Korean local corn and imported corn varieties. The results were as follows: Plant and stem height of Suweon 19 were 290.0 and 258.5cm respectively, and were higher than those of the other varieties, and those of Royal dent 100 were hither than the other imported corn variety. Grain yields of Suweon 19 and Royal dent 100 were 1,898 and 1,828kg per 10a respectively. Fresh matter yield of Snow dent 1 was similar with Suweon 19 and those were 6.536 and 6,513kg per 10a, respectively. Dry matter yields of Suweon 19, Snow dent 1 and Royal dent 100 were over 2,000kg per 10a. TDN content was the highest with 70.3% in Snow dent 1, and showed similar level with over 65% in all the varieties. TDN yield was the highest in Suweon 19(1,651.5 kg/10a) and showed in order of Royal dent 100 (1,538.5kg/10a) and Snow dent 1(1,522.9 kg/10a).

• Childhood Kidney Diseases
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• v.27 no.2
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• pp.70-75
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• 2023

Dent disease is a rare inherited kidney tubulopathy caused by mutations in either the CLCN5 (Dent disease 1) or OCRL1 (Dent disease 2) genes, and which is often underdiagnosed in practice. A diagnosis is clinically suspected in patients with low-molecular-weight proteinuria, hypercalciuria, and one of the following: hematuria, nephrolithiasis, nephrocalcinosis, hypophosphatemia, or chronic kidney disease. Inheritance is X-linked recessive, meaning, these symptoms are generally only found in males; female carriers may have mild phenotypes. Genetic testing is only a method to confirm the diagnosis, approximately 25% to 35% of patients have neither the CLCN5 nor OCRL1 pathogenic variants (Dent disease 3), making diagnosis more challenging. The genotype-phenotype correlations are not evident with the limited clinical data available. As with many other genetic diseases, the management of patients with Dent disease concentrates on symptom relief rather than any causative process. The current treatments are mainly supportive to reduce hypercalciuria and prevent nephrolithiasis. Chronic kidney disease progresses to end-stage between the ages of the third to fifth decades in 30% to 80% of affected males. In this review, we aimed to summarize the literature on Dent disease and reveal the clinical characteristics and molecular basis of Korean patients with Dent disease.

• Proceedings of the KACD Conference
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• 2001.11a
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• pp.558.1-558
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• 2001

Flowable resin composite is a relatively new restorative material. It has been reported that a low viscosity, low modulus intermediate resin applied between the bonding agent and restorative resin act as an "elastic buffer" that can relieve contraction stress. This in-vitro study aimed to evaluate the effect of flowable composite resin as a restorative material on regional tensile bond stredgth to cervical wedge shaped cavity walls. (omitted)

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2007.05a
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• pp.322-325
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• 2007

Dent resistance is an important characteristic to avoid damage on automotive outer panels. From a practical point of view, dents can be caused in a number of ways. Considering doors as an example, denting can occur from stone impacts or from the careless opening of an adjacently parked vehicle door. Denting can occur where the door surface is smooth and may not have sufficient curvature to resist dent. These exterior body parts are designed to improve dent resistance using a combination of work hardening and bake hardening. In brief, dent is affected by the shape of the parts and the material properties such as yield strength, strain and thickness. In this work, forming of door outer panel is investigated by Taguchi method. Main parameters are yield strength, thickness, blank size, blank holding force and so on. For the given value of design parameters, forming analysis of the thirty six cases are carried out according to L18 orthogonal array. After comparing the performance by simple conversion of simulation results into dent resistance, the final suggestion of the forming parameters is verified for the best improvement of dent resistance.

• Transactions of Materials Processing
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• v.16 no.4 s.94
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• pp.254-259
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• 2007

Dent resistance is an important characteristic to avoid damage on automotive outer panels. From a practical point of view, dents can be caused in a number of ways. Considering doors as an example, denting can occur from stone impacts or from the careless opening of an adjacently parked vehicle door. Denting can occur where the door surface is smooth and may not have sufficient curvature to resist dent. These exterior body parts are designed to improve dent resistance using a combination of work hardening and bake hardening. In brief, dent is affected by the shape of the parts and the material properties such as yield strength, strain and thickness. In this work, forming of door outer panel is investigated by Taguchi method. Main parameters are yield strength, thickness, blank size, blank holding force and so on. For the given value of design parameters, forming analysis of the eighteen cases are carried out according to L18 orthogonal array. After comparing the performance by simple conversion of simulation results into dent resistance, the final suggestion of the forming parameters is verified for the optimal improvement of dent resistance.

• Proceedings of the KIEE Conference
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• 1997.07e
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• pp.1900-1902
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• 1997

In order to obtain various waveforms of current pulse applied at the flashlamp, we have fabricated a Pulsed Nd:YAG laser by PFN with multiple-mesh formed LC network. we have obtained various waveforms of current pulse by adjusting the values of L and C, compared these waveforms of current pulse with laser beam, and then analyzed the laser output energy. We have got relations for $E_{TH}$ and $E_L$ at each mesh which supplies energy with flashlamp and found that output of Pulsed Nd:YAG Laser for 2-mesh, 5-mesh coincided with computer's simulation, PSPICE.

• Proceedings of the PSK Conference
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• 2003.04a
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• pp.134.1-134.1
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• 2003

Tempting to further understanding the biophysical mechanism of action of chlorhexidine, we examined effects of the antimicrobial agent(chlorhexidine digluconate) on rate of rotational mobility of liposomes of total lipids extracted from anaerobic bacterial outer membranes (Porphyromonas gingivalis outer membranes). (omitted)