• 충청수학회지
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• 제23권4호
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• pp.845-852
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• 2010

A nonlinear algebraic equation f(x) = 0 is considered to find a root with integer multiplicity $m{\geq}1$. A variant of Newton-secant method for a multiple root is proposed below: for n = 0, 1, $2{\cdots}$ $$x_{n+1}=x_n-\frac{f(x_n)^2}{f^{\prime}(x_n)\{f(x_n)-{\lambda}f(x_n-\frac{f(x_n)}{f^{\prime}(x_n)})\}$$, $$\lambda=\{_{1,\;if\;m=1.}^{(\frac{m}{m-1})^{m-1},\;if\;m{\geq}2$$ It is shown that the method has third-order convergence and its asymptotic error constant is expressed in terms of m. Numerical examples successfully verified the proposed scheme with high-precision Mathematica programming.

• 대한한의학회지
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• 제34권1호
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• pp.89-102
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• 2013

Objectives: This study aimed to evaluate the effects of root of Curcumin longa (RCL) on LPS-induced COPD (chronic obstructive pulmonary disease) model. Materials and Methods: Extract of RCL was treated to RAW 264.7 cells and LPS-induced COPD mouse model. Then, various parameters such as cell-based protective activity, airflow limitation, accumulation of immune cells and histopathological finding were analyzed. Results: RCL showed a protective effect on LPS-induced cytotoxicity in RAW 264.7 cells. RCL treatment also revealed a protective effect on LPS-induced lung injury in a COPD mouse model. This effect was demonstrated via the reduction of accumulation of immune cells and pathophysiological regulation of caspase 3, elastin and collagen in lung tissue. Conclusions: These data suggest that RCL has a pharmaceutical property on lung injury. This study provides scientific evidence for the efficacy of RCL for clinical application to COPD patients.

• Journal of Forest and Environmental Science
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• 제30권1호
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• pp.113-119
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• 2014

To examine the soil reinforcement by the shrub with shallow root systems for slope stability, we developed insitu apparatus for direct shear test and conducted the insitu field tests for Lespedeza cyrtobotrya, a representative revegetation species for artificial hillslopes. The insitu field tests were conducted for two different soil conditions (the rooted soils and non-rooted soils) and we then compared the experimental values with those calculated from the Wu model. The results showed that the soil reinforcement derived from the insitu field tests ranged from 0.01525 to 0.1438 $kgf/cm^2$ while the one calculated from the Wu model ranged from 0.1952 to 0.2696 $kgf/cm^2$. Our finding suggests more field tests are needed to collect the related parameters in the model application thereby predicting the reliable soil reinforcement by the shrub root systems.

• Advances in Traditional Medicine
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• 제6권3호
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• pp.174-178
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• 2006

The ethanolic extract of Leucas aspera root was studied for its effect on the central nervous system (CNS) using pentobarbitone induced sleeping time test, the open field test and the hole cross test in Swiss albino mice. The present investigation revealed that the extract at the doses of 250 and 500 mg/kg, significantly prolonged the pentobarbitone induced sleeping time in mice though the onset of sleep was delayed as compared to control. In open field test the depressing effect was prominent from the second observation period (30 min) and persisted throughout the entire experimental period (240 min). In the hole cross test, the depressing effect was observed significant from the third observation period (60 min) and persisted up to the seventh observation period (240 min) except at fourth observation (90 min) for 250 mg dose group and depressing effect was significant from second observation (30 min) up to seventh observation period (240 min) for 500 mg dose group. These results support the finding that Leucas aspera root may contain biologically active constituent(s) having CNS activity.

• 치과방사선
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• 제28권1호
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• pp.285-297
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• 1998

This report details a case of 8-year-old girl showing failure of odontogenesis after chemo-radiation therapy for the rhabdomyosarcoma at the age of 4. The observed results were as follows : 1. Past history revealed that she had received for a total radiation dose of 4430cGy, 29 fractions in 6 weeks and chemotherapy with vincristine, actinomycin D and cytoxan, followed as maintenance phase for 2 years. 2. The patient was symptom -free and appointed for the treatment of multiple dental caries. 3. Oral examination showed hypoplastic enamel on whole erupted permanent teeth and showed retarded eruption. 4. Conventional radiograms showed failure of root development including abrupt cessation of root formation and root agenesis, and microdontia, missing teeth, irregular enamel, dislocation of the impacted teeth. Additional finding showed good healing bone pattern on the left mandibular ramus and angle area. 5. Cephalometric analysis revealed failure of bite raising due to incomplete eruption of all the first molars and made it possible to suspect entrapped mandibular growth and then Class II tendency growth. 6. There was correlation between the time of chemo-radiation therapy and the damage of the teeth.

• Journal of Korean Neurosurgical Society
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• 제45권6호
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• pp.336-340
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• 2009

Objective : The factors that influence the prognosis of patients with hemifacial spasm (HFS) treated by microvascular decompression (MVD) have not been definitely established. We report a prospective study evaluating the prognostic factors in patients undergoing MVD for HFS. Methods : From January 2004 to September 2006, the authors prospectively studied a series of 293 patients who underwent MVD for HFS. We prospectively analyzed a number of variables in order to evaluate the predictive value of independent variables for the prognosis of patients undergoing MVD. The patients were followed-up at regular intervals and divided into as cured and unsatisfactory groups based on symptom relief. Uni- and multivariate analyses were performed using logistic regression models. Results : A total 273 of 293 (94.2%) patients achieved symptom relief within one year after the operation. Intraoperatively, the indentation of the root exit zone was observed in 259 (88.5%) patients. Uni- and multivariate analyses revealed that the symptoms at postoperative 3 months (p<0.001) and indentation of the root exit zone (p=0.036) were associated with good outcomes. Conclusion : The intraoperative finding of root exit zone indentation will help physicians determine the prognosis in patients with HFS. To predict the prognosis of HFS, a regular follow-up period of at least 3 months following MVD should be required.

• 디지털융복합연구
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• 제12권8호
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• pp.77-84
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• 2014

TRIZ는 원래 러시아인인 알트슐러에 의해 개발되어 기술 분야의 문제 해결에 활용 되어 왔지만, 최근에는 Darrell Mann에 의해 비 기술 영역에도 적용이 되기 시작하였다. 국내에는 1995년 LG전자에서 최초로 도입하여 현재는 삼성, 포스코 등 많은 기업들이 문제 해결도구로 사용하고 있다. TRIZ 문제 해결 방법은 문제를 정의하고, RCA(Root Cause Analysis)를 통해 근본원인을 찾아내어 기술적 모순과 물리적 모순을 정의 하고 있다. TRIZ는 모순을 극복하는 것이 문제를 해결하는 것이다. 본 연구는 문제 해결 방법인 TRIZ 원리를 이용하여 비기술 분야인 물류 영역의 개선에 적용하고자 하였다. 실제 "L" 기업의 물류 재작업이라는 물류 운영 개선을 하기 위해 TRIZ 방법론 중 RCA(Root Cause Analysis)분석, 모순 정의, 40가지 발명원리를 사용하여 문제 해결을 위한 아이디어 도출 및 적용 하였다. 본 연구는 TRIZ를 비기술 분야에 활용하고자 하는 향후 연구자들에게 도움이 되고자 하였다.

• 한국안전학회지
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• 제36권5호
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• pp.43-51
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• 2021

Incident investigation is one of the most important processes among various other safety management methods to prevent industrial accidents. Finding the root causes of accidents, eliminating hazards, and improving safety are the most important purposes of investigating accidents. During the investigation process, root cause analysis (RCA) techniques are used to effectively identify RCA. Over the past few decades, over 30 RCA methods have been developed. These techniques are being widely used in some industries, such as the nuclear and aircraft industries; however, most of the RCA techniques require professional knowledge and special training, making it difficult for safety managers in their respective fields to understand and apply them. Therefore, managers of general industrial sites are rarely present at the scene of actual accident investigations, and they cannot contribute much to the purpose and effectiveness of these investigations. In this study, to address these issues, we developed an RCA technique to facilitate root cause investigation of accidents in real-world industrial sites. To develop new techniques, Systematic Cause Analysis Technique (SCAT), one of the RCA techniques, was used to investigate incidents in the enterprise over three years. We also utilized feature analysis and other papers from existing RCA techniques. To verify its effectiveness, the technique proposed was also applied to the accident case. The technique developed can easily identify and analyze the root cause of an accident and help industrial managers. It can also identify the root cause category where accidents are concentrated and use this data to establish guidelines for preventing future accidents and, thus, focus on prioritizing improvement initiatives.

• 충청수학회지
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• 제25권4호
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• pp.669-676
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• 2012

In this note we extend one well-known iteration formula to derive new third-order methods for solving a nonlinear equation. The comparison with other methods is given.

• 한국수학사학회지
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• 제15권3호
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• pp.25-34
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• 2002

This paper explains methods of numerical analysis which appear on Cardano's Ars Magna and Newton's Principia. Cardano's method is secant method, but its actual al]plication is severely limited by technical difficulties. Newton's method is what nowadays called Newton-Raphson's method. But mysteriously, Newton's explanation had been forgotten for two hundred years, until Adams rediscovered it. Newton had even explained finding the root using the second degree Taylor's polynomial, which shows Newton's greatness.