• Structural Engineering and Mechanics
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• v.46 no.3
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• pp.371-385
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• 2013

Vibration isolators and anti-vibration mounts are ideal, for example, in creating floating floors for gymnasiums, or performance spaces. However, it is well-known that there are great difficulties on isolating vibration transmission in structural steel components, especially steel floors. Besides, the selection of inertia blocks, which are usually used by engineers as an effective vibration control measure, is usually based on crude methods or the experience of the engineers. Thus, no simple method or indices have been available for assessing the effect of inertia blocks on vibration isolation or stability of vibratory systems. Thus, the aims of this research are to provide further background description using a FE model and present and implement a modal approach, that was validated experimentally, the latter assisting in providing improved understanding of the vibration transmission phenomenon in steel buildings excited by a velocity-source type of excitation. A better visualization of the mean-square velocity distribution in the frequency domain is presented using the concept of modal expansion. Finally, the variation of the mean-square velocity with frequency, whilst varying mass and/or stiffness of the coupled system, is presented.

• Bulletin of the Korean Space Science Society
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• 2008.10a
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• pp.22.1-22.1
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• 2008

Media company is not a business which sells news and information but a company sells audience's attention. Advertisers estimate audience's quantity and quality which pay attention to media and pay the cost. Thus drawing audience's attention is a natural and instinctive behavior for survival of media company. News doesn't deliver the fact just as it. That's impossible. News is a commodity made by processing and selection of the media company and journalist. On the process, judge of values is involved and limitation of time and place of media is considered. If scientists understand media's character truly, their misunderstanding about media company and journalist may be cleared up. In this society, media is not a being to ignore, particularly for big science like space science which spends huge public capital. Nowadays, space science meets the time to take the leap in Korea. However that can be crisis cause of uncertainty of science activity. When the crisis which no one desires happens, preparation needs for new opportunity. We can take the crisis as a chance. Understanding about media and public will be the first step for this preparation.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 2006.11a
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• pp.134-137
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• 2006

Satisfying the customer orders with a short lead-time is one of the essential and competitive factors for business units under a mass customization environment. To shorten the lead-time for fulfilling various orders entails the production capacity expansion and efficient operational policy. Most business firms utilize the multiple production lines or facilities to cope with this business and manufacturing environment by making the manufacturing and distribution more flexible. In this study, we introduce the operational problem determining the joint production and delivery policy in an environment where multiple products are manufactured with more than one production lines. Also, we propose the heuristic solution approach for determining the product-line selection and joint lot size for this problem.

• Journal of Welding and Joining
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• v.15 no.1
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• pp.135-148
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• 1997

It was attempted to improve wear resistance and durability under the load surface pressure that make a formation of the thick (mm-order) hard-surfacing layer for aluminum alloy of 5083. The thick hard layers were formed on the surface of 5083 by TIG overlay method. Al-(25.4, 33.6, 45.7 mass%) Cu filler metals which were newly developed were overlaid on two base metals forming the one bead, one layer and two layers. The investigation was made on the characteristics of hardening and wear resistance in relation to the microstructure of overlaid layers with selection of optimum overlaying condition.

• KSTLE International Journal
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• v.1 no.2
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• pp.107-112
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• 2000

In case of the limitation of Deep RIE fabrication far Micro Gas Turbine, bearing aspect ratio is limited in very small value. The characteristics such as pressure distribution, load capacity and non-linearity of a short bearing of L/D=0.083 and a conventional bearing of L/D=1.0 with coupled boundary effects are investigated for Micro Gas Turbine bearings. The coupled effect was analyzed by mass conservation at coupled end area. The results, increasing load capacity and non-linearity due to the coupled effect of thrust and journal bearing, are obtained and the selection of journal bearing type is discussed.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2004.08a
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• pp.37-44
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• 2004

Continuous depth data are often required in applications of both onboard systems and maritime simulation. But data available are usually discrete and irregularly distributed. Based on the neuron network technique, methods of interpolation to the charted depth are suggested in this paper. Two algorithms based on Levenberg-Marquardt back-propaganda and radial-basis function networks are investigated respectively. A dynamic neuron network system is developed which satisfies both real time and mass processing applications. Using hyperbolic paraboloid and typical chart area, effectiveness of the algorithms is tested and error analysis presented. Special process in practical applications such as partition of lager areas, normalization and selection of depth contour data are also illustrated.

• Journal of the Korean Data and Information Science Society
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• v.26 no.3
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• pp.773-779
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• 2015

We study a statistical analysis about the fifth wave data of the Korea National Health and Nutrition Examination Survey based on linear regression models with measurement errors. The data is obtained from a national population-based complex survey. To demonstrate the availability of measurement error models, two results between the general linear regression model and measurement error model are compared based on the model selection criteria which are Akaike information criterion and Bayesian information criterion. For our study, we use the simulation extrapolation algorithm for measurement error model and the jackknife method for the estimation of standard errors.

• 유체기계공업학회:학술대회논문집
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• 2000.12a
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• pp.99-103
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• 2000

This paper describes the development of standard series for turbo blowers. In mass production system, it is very required to standardize blowers to improve the productivity of ordering, estimating, manufacturing. To standardize blowers, we performed researches on the effects of $b_1$(impeller inlet width), $b_2$(impeller outlet width), ${\beta}_1$(blade inlet angle), ${\beta}_2$(blade outlet angle), Z(number of blades) of impellers and geometry of casing experimentally. Through this study, we chose the several best model of turbo blowers with high efficiency and low noise, which represent each specific speed series 63, 80, 100, 125, 160, 200, 250, 315. After the development of such standardized blowers, the test results are used to prepare the fan geometry and performance database for a selection software.

• Imaging Science in Dentistry
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• v.41 no.1
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• pp.1-6
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• 2011

Purpose : The purpose of this review is to evaluate the possibility of panoramic radiography as a national oral examination tool. Materials and Methods : This report was carried out by review of the literatures. Results : Panoramic radiography has sufficient diagnostic accuracy in dental caries, periodontal diseases, and other lesions. Also, the effective dose of panoramic radiography is lower than traditional full-mouth periapical radiography. Conclusion : Panoramic radiography will improve the efficacy of dental examination in national oral examination. However, more studies are required to evaluate the benefit, financial cost, and operation time and also to make selection criteria and quality management program.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2010.05a
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• pp.5-5
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• 2010

Selection of specific medicinal sources as well as bioactive compounds is important for the preparation of medicine and related products with good quality. It is necessary to pay close attention for choosing correct medicinal sources, particularly in case of medicinal plants, because of their diversity, which can affect the quality and efficacy of medicine. Discrimination of plants based on morphological or genetic characteristics has been used as a conventional classification method of pharmaceutical sources so far; however, more need demands more general methods for accurate quality assessment of medicinal plants. In this study, ultra performance liquid chromatography/quadrupole time-of-flight mass spectrometry (UPLC/Q-TOF MS) technique applied to this metabolic profiling is a powerful tool due to its higher sensitivity, resolution, and speed compared to conventional HPLC technique. The metabolite profiling of several medicinal plants including Panax ginseng was carried out using UPLC/Q-TOF MS and total metabolites were then subsequently applied to various statistical tools to compare the patterns. The developed metabolomics tool with UPLC/Q-TOF MS successfully identified and classified the samples tested according to their origins.