• Journal of the Semiconductor & Display Technology
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• v.8 no.3
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• pp.31-37
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• 2009

This paper presents one and two dimensional simulation results with discontinuous features (shocks) of capacitively coupled rf plasmas. The model consists of the first two and three moments of the Boltzmann equation for the ion and electron fluids respectively, coupled to Poisson's equation for the self-consistent electric field. The local field and drift-diffusion approximations are not employed, and as a result the charged species conservation equations are hyperbolic in nature. Hyperbolic equations may develop discontinuous solutions even if their initial conditions are smooth. Indeed, in this work, secondary electron emission is shown to produce transient electron shock waves. These shocks form at the boundary between the cathodic sheath (CS) and the quasi-neutral (QN) bulk region. In the CS, the electrons emitted from the electrode are accelerated to supersonic velocities due to the large electric field. On the other hand, in the QN the electric field is not significant and electrons have small directed velocities. Therefore, at the transition between these regions, the electron fluid decelerates from a supersonic to a subsonic velocity in the direction of flow and a jump in the electron velocity develops. The presented numerical results are consistent with both experimental observations and kinetic simulations.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.15 no.2
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• pp.302-314
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• 2002

Shibyukmiyouki-Eum was a drug that treated carbuncle and cellulitis. So, the purpose of this study was to investigate effect of Shibyukmiyouki-Eum on the anticancer and inhibitive effects of the secondary effects by anticarcinogen We used Shibyukmiyouki-Eum extract(SYE) with freeze-dried, 8wks-old male mice(balb／c, ICR) and cancer cell lines(L1210. S-180) for this Study, The proliferation of cells was tested using a colorimetric tetrazoliun assay(MTT assay). and measurement of WBC, RBC, hemoglobin and platelet was tested by a automated hematology analyzer. The results of this study were obtained as follow; SYE was showed significantly cytotoxicity on the L1210 and S-180 cell lines. increased proliferation of thymocytes decreased by anticarcinogen. In combined effects of SYE and vincristine(0.005㎎／kg), SYE was significantly inhibited proliferation of L1210 cells and significantly increased proliferation of thymocytes. Also SYE was significantly increased count of WBC. platelet and increased count of RBC, hemoglobin. These results suggest that SYE has not only anticancar action but inhibitive effects of on the secondary effects by anticarcinogen.

• Tribology and Lubricants
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• v.34 no.6
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• pp.262-269
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• 2018

In this work the friction and wear characteristics of the gray cast iron surface processed by broaching method, which is widely used in the machinery industry, were investigated. The broaching process is mainly used for mass production because it has high dimensional accuracy and processing speed, but the defects on surface can be easily generated. In order to improve the tribological characteristics, the approach was to reduce the roughness and hardness of the surface by adding a machining process to the broaching specimen. The secondary machining process using abrasive grains produces low roughness and hardness than broaching because it has high tool accuracy and removes the work hardened surface. The friction coefficient and the wear rate were assessed using a reciprocating-type tribotester to analyze the effects of surface finishing on the tribological properties. The friction tests were conducted under dry and lubricated conditions. The test results showed that the reduction of surface roughness and hardness through secondary machining process in lubricated condition improved the friction and wear characteristics. The reason why the same results did not appear in a dry condition was that wear occurred more rapidly than in lubricated condition. Thus, the positive effect of roughness and hardness of the surface obtained through the secondary machining process was not observed.

• Journal of Korean Port Research
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• v.12 no.1
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• pp.75-86
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• 1998

To design a coastal structure in the nearshore region, engineers must have means to estimate wave climate. Waves, approaching the surf zone from offshore, experience changes caused by combined effects of bathymetric variations, interference of man-made structure, and nonlinear interactions among wave trains. This paper has attempted to find out the effects of two of the more subtle phenomena involving nonlinear shallow water waves, amplitude dispersion and secondary wave generation. Boussinesq-type equations can be used to model the nonlinear transformation of surface waves in shallow water due to effect of shoaling, refraction, diffraction, and reflection. In this paper, generalized Boussinesq equations under the complex bottom condition is derived using the depth averaged velocity with the series expansion of the velocity potential as a product of powers of the depth of flow. A time stepping finite difference method is used to solve the derived equation. Numerical results are compared to hydraulic model results. The result with the non-linear dispersive wave equation can describe an interesting transformation a sinusoidal wave to one with a cnoidal aspect of a rapid degradation into modulated high frequency waves and transient secondary waves in an intermediate region. The amplitude dispersion of the primary wave crest results in a convex wave front after passing through the shoal and the secondary waves generated by the shoal diffracted in a radial manner into surrounding waters.

• Clinical and Experimental Reproductive Medicine
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• v.51 no.1
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• pp.63-68
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• 2024

Objective: This study was conducted to investigate the impact of previous delivery mode on pregnancy outcomes in patients with secondary infertility after frozen-thawed embryo transfer. Methods: This prospective observational study included 140 patients experiencing secondary infertility. Of these, 70 patients had a previous cesarean delivery (CD), while the remaining 70 patients had a previous normal vaginal delivery (NVD). The primary outcome was the implantation rate. The secondary outcomes included rates of clinical pregnancy, chemical pregnancy, miscarriage, and ectopic pregnancy. Results: The comparison of all fertility outcomes between the two groups revealed no statistically significant differences. The implantation rate was 40.4% in the CD group and 41.7% in the NVD group (p=0.842). The clinical pregnancy rate was 50% in the CD group and 49.3% in the NVD group (p=0.932), while the chemical pregnancy rate was 14.6% in the CD group and 19% in the NVD group (p=0.591). The miscarriage rates in the CD and NVD groups were 20% and 17.6%, respectively (p=0.803). One case of tubal ectopic pregnancy occurred in the NVD group (1.4%). Conclusion: The mode of prior delivery did not significantly impact pregnancy outcomes following frozen-thawed embryo transfer.

• Journal of dental hygiene science
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• v.14 no.4
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• pp.589-596
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• 2014

This study was designed to investigate the using status and awareness of pit and fissure sealant, and how it affects on secondary caries when performed on above of initial caries. After classifying 446 occlusal surface into four groups, performed pit and fissure sealant, induced artificial caries, used DIAGNOdent (Kavo) to measure degree of secondary caries. Also, distributed a questionnaire on dental clinic in metropolitan area to find out using status and awareness of pit and fissure sealant, the following results were obtained. 1) On inspection and percussion, Group 4 corresponding to the enamel caries showed the highest secondary caries after sealant and was statistically significant difference in the order of initial group, stained group, sound group (p<0.05). 2) Inspection showed the highest percentage on tooth fissure caries diagnostic methods before sealant. 3) 56.6% didn't know about DIAGNOdent, 91.6% didn't have it. 4) In clinically, the most cause of secondary caries after sealant was a broken sealant, making caries on the downward. Based on the results of above study, degree of caries under sealant could affect on secondary caries, needs publicity about the use and necessity of objective fluorescence device.

• Korean Journal of Social Welfare
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• v.63 no.1
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• pp.159-185
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• 2011

This study aims to find out the determinants of male police officers' investigative behavior(active investigation vs. secondary victimization) of sexual violence. For this purpose, a hypothetical model which explains the relationships among the 5 variables (knowledge of law about the investigative role, perception of the protective & connective role, prejudice against the sexual violence, active investigation, and secondary victimization) was developed. Using the data collected from 354 male police officers of 3 cities in Gyeongnam area, the hypothetical model was tested. For data analysis, a structural equation modeling was used, and the final model was found(CFI=0.947, IFI=0.948, RMSEA=0.048). As a result of analyzing the model, the followings were found: (1) Active investigation was increased by knowledge of law about the investigative role, and perception of the protective & connective role, while decreased by prejudice against the sexual violence. (2) Secondary vicimization was decreased by knowledge of law about the investigative role. (3) Prejudice against the sexual violence mediate the effects of knowledge of law about the investigative role, and perception of the protective & connective role on active investigation. (4) Prejudice against the sexual violence was found to have no significant effect on secondary victimization. Based on the findings, multi-educational programs, protocols on investigation of sexual violence, professionalization of the police, and changes in investigation environment as well as a system of collaboration and cooperation between police officer and social worker were suggested as a way to increase active investigation and to decrease secondary victimization.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2008.11a
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• pp.97-98
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• 2008

• Proceedings of the Korean Magnestics Society Conference
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• 1996.10a
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• pp.98-99
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• 1996

• 한국연소학회:학술대회논문집
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• 2015.12a
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• pp.135-137
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• 2015