• Journal of Preventive Medicine and Public Health
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• 제49권2호
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• pp.129-133
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• 2016

Objectives: The systematic review (SR) is a research methodology that aims to synthesize related evidence. Updating previously conducted SRs is necessary when new evidence has been produced, but no consensus has yet emerged on the appropriate update methodology. The authors have developed a new SR update method called 'adaptive meta-analysis' (AMA) using the 'cited by', 'similar articles', and 'related articles' citation discovery tools in the PubMed and Scopus databases. This study evaluates the usefulness of these citation discovery tools for updating SRs. Methods: Lists were constructed by applying the citation discovery tools in the two databases to the articles analyzed by a published SR. The degree of overlap between the lists and distribution of excluded results were evaluated. Results: The articles ultimately selected for the SR update meta-analysis were found in the lists obtained from the 'cited by' and 'similar' tools in PubMed. Most of the selected articles appeared in both the 'cited by' lists in Scopus and PubMed. The Scopus 'related' tool did not identify the appropriate articles. Conclusions: The AMA, which involves using both citation discovery tools in PubMed, and optionally, the 'related' tool in Scopus, was found to be useful for updating an SR.

• 한국분말재료학회지
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• 제16권1호
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• pp.43-49
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• 2009

Titanium carbides are widely used for cutting tools and grinding wheels, because of their superior physical properties such as high melting temperature, high hardness, high wear resistance, good thermal conductivity and excellent thermal shock resistance. The common synthesizing method for the titanium carbide powders is carbo-thermal reduction from the mixtures of titanium oxide($TiO_2$) and carbon black. The purpose of the present research is to fabricate nano TiC powders using titanium salt and titanium hydride by the mechanochemical process(MCP). The initial elements used in this experiment are liquid $TiCl_4$(99.9%), $TiH_2$(99.9%) and active carbon(<$32{\mu}m$, 99.9%). Mg powders were added to the $TiCl_4$ solution in order to induce the reaction with Cl-. The weight ratios of the carbon and Mg powders were theoretically calculated. The TiC and $MgCl_2$ powders were milled in the planetary milling jar for 10 hours. The 40 nm TiC powders were fabricated by wet milling for 4 hours from the $TiCl_4$+C+Mg solution, and 300 nm TiC particles were obtained by using titanium hydride.

• 한국항공우주학회지
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• 제38권2호
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• pp.188-194
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• 2010

본 연구에서는 영상레이다 (SAR)의 영상품질 분석 변수 및 확장 보간법, 배경레벨 제거 기법 등의 분석 기법을 정의하고 이를 바탕으로 SAR 영상품질 분석 툴을 개발하였다. 개발된 SAR 영상품질 분석 툴은 크게 점 표적 분석 (PTA) 모듈, 분산 표적 분석 (DTA) 모듈, 모호성 분석 (AMA) 모듈, NESZ 분석 (NESZA) 모듈, 총 4개의 주요 모듈로 구성된다. 개발 툴은 SAR 제품 파일 포맷에서 다양한 시스템 파라미터 추출하고, 이를 바탕으로 임펄스 응답 특성, 방사 성능, 모호성 등의 SAR 영상 품질 변수를 계산한다.

• 한국분말재료학회지
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• 제12권3호
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• pp.174-178
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• 2005

This paper deals with the fabrication of titanium carbide using fine titanium hydride. The ratio of $TiH_2$ and C (Activated carbon) was 1:1 (mol) and milled in a planetary ball mill at a ball-to-powder weight ratio of 20:1. Thereafter, TGA was performed at $1400^{\circ}C$ to observe change of weight with milling time. Titanium carbide was obtained by using tempering the milled powders at $1100-1500^{\circ}C$. The microstructures of titanium carbide as well as the change of the lattice parameters and particle size have been studied by X-ray diffraction (XRD) and scanning electron microscopy (SEM).

• 한국분말야금학회:학술대회논문집
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• 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part 1
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• pp.635-636
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• 2006

In this study, the diffusion behaviors of C and Co in liquid phase sintering of WC-Co system were investigated whether these two components diffused in the same direction in case of having opposite gradient each other with not being $\eta$ phase. The green compacts with controlled compositions in not being of $\eta$ phase and gradient composition which one is WC-5Co-1.2%C, the other is WC-XCo-0.2%C (where X = 5, 10, 15, 20, 25) were sintered at $1350^{\circ}C$ and $1400^{\circ}C$ and then the diffusion behaviors of C and Co were investigated by analyses of compositional change, also determined for microstructure and microhardness. Also, same testing was carried out on the specimens with dual layers sintered in upright and reverse positions to evaluate the effect of gravity on the diffusion in liquid Co. From the results of this study, we can find the fact that the direction of diffusion for C and Co in WC-Co system during liquid phase sintering was different and the effect of gravity for the liquid was insignificant. Also other physical properties were changed on the diffusion of elements.

• The Journal of Asian Finance, Economics and Business
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• 제8권4호
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• pp.601-611
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• 2021

There are many asset prices which are interlinked and have a bearing on the stock market index. Studies have shown that the interrelationship among these asset prices vary and are inconsistent. The ultimate aim of this study is to examine the dynamic relationship between gold price, oil price, exchange rate and stock index. Monthly time series data has been utilized by the researcher to examine the interrelationship between four variables. The relationship among stock exchange rate index, oil price and gold price have been undertaken using regression and granger causality test. The results indicate that the exchange rate and oil price have an indirect influence on NIFTY; whereas gold price had a direct impact on NIFTY. It is evident from the results that volatility in the price of gold is mainly dependent on the exchange rate and vice versa. All the variables affect NIFTY in some way or the other. However, gold has a direct and vital relationship. From the study findings, it can be concluded that macroeconomic variables like commodity prices and foreign exchange rate, gold and oil, have a strong relationship on the return on securities at the national stock exchange of India.

• Tuberculosis and Respiratory Diseases
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• 제77권2호
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• pp.65-72
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• 2014

Background: It is valuable to find the potential activity of regulating the excessive mucin secretion by the compounds derived from various medicinal plants. We investigated whether aqueous extract of the root bark of Morus alba L. (AMA), kuwanon E, kuwanon G, mulberrofuran G, and morusin significantly affect the secretion and production of airway mucin using in vivo and in vitro experimental models. Methods: Effect of AMA was examined on hypersecretion of airway mucin in sulfur dioxide-induced acute bronchitis in rats. Confluent NCI-H292 cells were pretreated with ethanolic extract, kuwanon E, kuwanon G, mulberrofuran G, or morusin for 30 minutes and then stimulated with phorbol 12-myristate 13-acetate (PMA) for 24 hours. The MUC5AC mucin secretion and production were measured by enzyme-linked immunosorbent assay. Results: AMA stimulated the secretion of airway mucin in sulfur dioxide-induced bronchitis rat model; aqueous extract, ethanolic extract, kuwanon E, kuwanon G, mulberrofuran G and morusin inhibited the production of MUC5AC mucin induced by PMA from NCI-H292 cells, respectively. Conclusion: These results suggest that extract of the root bark and the natural products derived from Morus alba L. can regulate the secretion and production of airway mucin and, at least in part, explains the folk use of extract of Morus alba L. as mucoregulators in diverse inflammatory pulmonary diseases.

• 대한예방의학회:학술대회논문집
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• 대한예방의학회 1993년도 제45차 추계 학술대회 연제집
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• pp.95-96
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• 1993

• 전자공학회지
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• 제22권3호
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• pp.92-105
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• 1995

각 분야에서 고화질 고해상도의 Flat Panel Display(FPD)에 대한 요구가 급증하고 있으며, FPD 소자들도 다양하다. FPD를 위한 구동방식은 근본적으로 matrix addroessing 방식을 사용하지만 FPD 소자의 동작 원리, 특성, 구동상의 문제점 등에 따라서 구동방식도 매우 다양하다. 다양한 FPD 소자들이 구동 방식과 구동회로를 다 살펴볼 수 없으므로 본고에서는 FPD소자인 PDP, EL, LED, EC, LCD, DMD, AMA, GLV, FED 등의 동작 원리를 설명하고, 이 소자들 중에서 AMLCD와 dc-PDP 소자의 구동방식과 구동회로에 대하여 논의한다. AMLCD의 구동방식으로는 펄스 구동 방식과 용량 구동 방식을 살펴보고, AMLCD의 문제점들을 극복할 수 있는 방법들을 설명한다. dc-PDP의 구동 방법인 pulse-memory 구동방식과 새로운 pulse-memory 구동 방식을 살펴보았다.

• 한국분말야금학회:학술대회논문집
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• 한국분말야금학회 2004년도 International Symposium on Powder Materials and Processing
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• pp.48-48
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• 2004