• Smart Structures and Systems
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• 제20권6호
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• pp.641-656
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• 2017

The effects of vertical component of earthquakes on torsional amplification due to mass eccentricity in seismic responses of base-isolated structures subjected to near-field ground motions are studied in this paper. 3-, 6- and 9-story superstructures and aspect ratios of 1, 2 and 3 have been modeled as steel special moment frames mounted on Triple Concave Friction Pendulum (TCFP) bearings considering different period and damping ratios. Three-dimensional linear superstructures resting on nonlinear isolators are subjected to both 2 and 3 component near-field ground motions. Effects of mass eccentricity and vertical component of 25 near-field earthquakes on the seismic responses including maximum isolator displacement and base shear as well as peak superstructure acceleration are studied. The results indicate that the effect of vertical component on the responses of asymmetric structures, especially on the base shear is significant. Therefore, it can be claimed that in the absence of the vertical component, mass eccentricity has a little effect on the base shear increase. Additionally, the impact of this component on acceleration is remarkable so the roof acceleration of a nine-story structure has been increased 1.67 times, compared to the case that the structure is subjected to only horizontal components of earthquakes.

• 한국정밀공학회지
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• 제5권1호
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• pp.84-93
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• 1988

The on-line detection of the chip flow is one of the most important technologies in com- pletly automatic operation of machine tool, such as FMS and Unmanned Factories. This problem has been studied by many researchers, however, it is not solved as yet. For the recognition of chip flow in this study, the dynamic cutting force components due to the chip breaking were measured by dynamometer of piezo-electric type, and the frequency components of cutting force were also analyzed. From the measured results, the effect of cutting conditions and tool geometry on the dynamic cutting force component and chip formation were investigated in addition to the relationships between frequency of chip breaking (fB) and side serrated crack (fC) of chip. As a result, the following conclusions were obtaianed. 1) The chip formations have a large effect on the dynamic cutting force components. When chip breaking takes place, the dynamic cutting force component greatly increases, and the peridoic components appear, which correspond to maximum peak- frequency. 2) The crater wear of tool has a good effect on the chip control causing the chiup to be formed as upward-curl shape. In this case, the dymamic cutting force component greatly increases also 3) fB and fC of chip are closely corelated, and fC of chips has a large effect on the change of the situation of chip flow and dynamic cutting force component. 4) Under wide cutting conditions, the limit value (1.0 kgf) of dynamic cutting force component exists between the broken and continuous chips. Accordingly, this value is suitable for recognition of chip flow in on-line control of the cutting process.

• 한국안전학회지
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• 제7권3호
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• pp.53-59
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• 1992

A general theory is developed which enables closed-cup flash points of mixtures of flammable and non-flammable liquid to be estimated from a knowledge of a certain properties of flammability diagram by thermodynamic method. The estimated equations is shown the effect of both the flame inhibiting properties of the vapor of the non-flammable component and the relative volatility of that component. The vapor phase flame inhibition effect results in a even greater elevation of flash points than the rotative volatility of that component. Especially in cases of similar vapor phase flame inhibition of the non-flammable component, the rotative volatility is affected greater elevation of flash points(extinguishing effect).

• Steel and Composite Structures
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• 제38권2호
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• pp.141-150
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• 2021

In the present paper we have investigated the Stoneley wave propagation at the interface of two dissimilar homogeneous nonlocal magneto-thermoelastic media under the effect of hall current applied to multi-dual-phase lag heat transfer. The secular equations of Stoneley waves have been derived by using appropriate boundary conditions. The wave characteristics such as attenuation coefficients, temperature distribution and phase velocity are computed and have been depicted graphically. Effect of nonlocal parameter and hall effect are studied on the attenuation coefficient, phase velocity, temperature distribution change, stress component and displacement component. Also, some particular cases have been discussed from the present study.

• Journal of Magnetics
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• 제11권4호
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• pp.160-163
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• 2006

We have prepared crystalline Ag nanoparticles with an average size of 4 nm in diameter by using an inductively coupled plasma reactor equipped with the liquid nitrogen cooling system. Our magnetic data show that the nano-sized effect of Ag nanoparticles on the magnetic properties is ferromagnetic, instead of a diamagnetic component of the Ag bulk and a superparamagnetic component of magnetic nanoparticles. We have also studied the magnetic properties of Ag-Cu nanocomposites with an opposite concentration profile between surface and core. These comparisons indicate that the ferromagnetic component strongly depends on the surface of Ag nanoparticles, while the paramagnetic component is strongly affected by the outer oxide layer, with the background of a diamagnetic component from the core of Ag.

• 대한한의학회지
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• 제29권4호
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• pp.55-67
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• 2008

Objectives: The purpose of this study was to investigate the effect of Hwangryunhaedok-tang, its major component Coptidis Rhizoma, and the major component of Coptidis Rhizoma, berberine, on the expression of behavioral sensitization induced by the repeated administration of nicotine. Methods: Experimental ratswere divided into 3 groups and each group treated with saline, nicotine, and Hwangryunhaedok-tang. Experiments were performed on 4 further groups, each group treated with saline, nicotine, Coptidis Rhizoma, and berberine. To obtain rats addicted todrugs, nicotine was injected repeatedly. After 3 days of withdrawal phase, on the 11th day, rats were re-exposed to nicotine and thus able to induce the expression of the activity sensitization phenomenon successfully. To examine the change of c-Fos in the brain of experimental rats with the nicotine-induced activity sensitization, their neurological activation rate was assessed by c-Fos staining with Fos-like immunihistochemistry of the dopamine releasing area, the striatum and the nucleus accumbens. Results: The result demonstrate that Hwangryunhaedok-tang, its major component Coptidis Rhizoma and berberine,the major component of Coptidis Rhizoma, significantly reduced the walking activity rate in the drug addict models induced by nicotine administration, and Coptidis Rhizoma and its major component berberine reduce the marker of the neurological activation c-Fos, and thus revealed an effect of suppressing drug addiction. Conclusions: These results suggest the possibility of Hwangryunhaedok-tang, its major component Coptidis Rhizoma and the major component of Coptidis Rhizoma, berberine,as therapeutic for nicotine addiction.

• Industrial Engineering and Management Systems
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• 제9권3호
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• pp.196-203
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• 2010

Make-to-forecast production is a way to realize high customization and fast responsiveness. This study firstly investigates the effect of introducing a common component in a make-to-forecast production environment. The common component can eliminate a modification step, which is a major cost component in make-to-forecast production. It is illustrated, however, that introducing a versatile component that merely covers several variants is unattractive, and thus adding values to the common component is inevitable in this environment. Secondly, an order-matching rule under the condition that two partially overlapped delivery lead time intervals exist is proposed. The rule considers the effect of matching orders to units that can cover both intervals. An alternative re-matching rule is also developed and examined. Numerical experiments clarify that the proposed rule generally realizes higher contribution ratio and lower percentages of orphans and rejected orders. The proposed re-matching rule increases the average contribution ratio at the expense of increased orphans and order rejections.

• 한국마이크로전자및패키징학회:학술대회논문집
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• 한국마이크로전자및패키징학회 2004년도 ISMP Pb-free solders and the PCB technologies related to Pb-free solders
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• pp.201-209
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• 2004

As the European Community's Directive on the Restriction of Hazardous Substances in Electrical and Electronic Equipment banning lead (Pb) in electronics products will take effect on July 1, 2006, most electronics manufacturers will be commencing with volume production of Pb-free components by the middle of 2004. Electrodeposited pure tin finishes on electronic components are a leading contender to replace the industry standard tin-lead. Commensurate with this shift will be a somewhat steep learning curve as manufacturers adapt a variety of equipment and processes to contend with the issues surrounding this critical, industry-wide material conversion. Since the electrodeposited finish directly influences the critical reliability characteristics of the component itself, the nature of the Pb-free component finish must be well characterized and understood. Only through a thorough examination of the attributes of the electroplated tin deposit can critical decisions be made regarding component finish reliability. This paper investigates the properties of electrodeposited tin that may have an effect on component reliability, namely, grain structure (size and shape), oxide formation, tin whisker formation, and solderability. Data will be presented from laboratory and production settings, with the objective being to enable manufacturers to draw their own conclusions regarding previously established perceptions and misconceptions about electrodeposited tin properties.

• 대한본초학회지
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• 제23권3호
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• pp.163-173
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• 2008

Objectives : Imyosan (IMS), a drug preparation comprised of Phellodendri Cortex (PC) and Atractylodis Rhizoma (AR), is commonly used as a traditional herbal medicine in Korea and China for the treatment of various inflammatory diseases. However, little is known about the effect of IMS and its component herbs on inflammatory mediators in RAW 264.7 cells. Therefore, in this study, methanol extracts of IMS and its component herbs were examined to determine if they inhibited inflammatory effects in RAW 264.7 cells. Methods : Cytotoxic activity of IJHT and its components on RAW 264.7 cells was using 5-(3-carboxymethoxyphenyl)-2H-tetrazolium inner salt (MTS) assay. The nitric oxide (NO) production was measured by Griess reagent system. And proinflammatory cytokines were measured by ELISA kit. The levels of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) expression were detected by western blot. Results : Methanol extract of IMS and its component herbs were significantly reduced iNOS and COX-2 expression as well as NO, PGE2, $IL-1{\beta}$ and IL-6 production in RAW 264.7 cells. Conclusions : The results of this study indicated that the anti-inflammatory effect of Imyosan extract is more potent than that of extracts of its component herbs in macrophages.

• 융합정보논문지
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• 제10권6호
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• pp.70-76
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• 2020

본 연구에서는 기업의 사회적 책임활동(Corporate Social Responsibiltiy, CSR)에 따라 판매관리비가 미래 기업성과에 미치는 영향에 차이가 발생하는지 살펴보았다. 판매관리비를 유지속성과 투자속성으로 구분한 뒤, 이 중에서 판매관리비의 투자속성에 초점을 맞추어 판매관리비의 투자속성이 미래 기업성과에 영향을 미치는지 여부에 대해 검토하고 이들 관계가 CSR의 수준에 따라 어떻게 영향을 받는지 분석하였다. 2012년부터 2017년까지 유가증권 시장에 상장된 국내 기업 중 CSR 평가 자료가 있는 968 기업-연도를 표본으로 하여 실증분석한 결과, 판매관리비의 투자속성이 미래 기업성과에 긍정적인 영향을 미친다는 것을 확인하였다. 이러한 관계는 CSR의 수준에 따라 달라지는데, CSR이 높을수록 판매관리비의 투자속성이 더 큰 양(+)의 효과로 미래 기업성과에 영향을 미치는 것으로 나타났다. 이는 기업이 사회적 책임활동에 적극적일수록 기업의 판매관리비 투자속성이 미래 기업성과에 미치는 긍정적인 영향이 커진다는 것을 시사한다.