• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2000년도 춘계학술대회 논문집
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• pp.842-845
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• 2000

It is essential to reduce stiction between the slider and the disk for super-smooth media such as glass disk for high density recording. We developed a stiction-reduced slider by fabricating mechanical bumps on the air bearing surface of the slider by indentation technique. This paper presents a possibility and concept of Stiction-Free-Slider which can operate on the data zone of a magnetic disk. The slider hat many bumps and their heights are in the tens of nm range. The SFS shows good performance on the data zone. Moreover, little wear of the bumps was observed when the preload was small.

• 대한미생물학회지
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• 제16권1호
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• pp.65-70
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• 1981

A microculture technique for the mixed lymphocyte culture test(MLC) in the sheep is described. The optimal incubation periods for the MLC are varied from 4 to 6 days depending on the sources of lymphocytes. It is found that a 2.5:1 stimulator-responder cell ratio and the responder cell concentration of $1{\times}10^5$ cells/well produce the highest($^3H$)-thymidine incorporation. Moreover cryopreservation of bovine lymphocytes results in satisfactory and reproducible MLC reaction. It is also evident that the MLC reactions of the sheep are under the control of histocompatibility matching between the stimulator cells and the responder cells. Significance of the technique as a too! for study on cell mediated immunity in sheep system, either normal or squamous cell carcinoma-bearing, are discussed.

• 한국전산유체공학회지
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• 제14권1호
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• pp.86-95
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• 2009

A kinetic theory analysis is used to study the ultra-thin gas flow field in gas bearings. The Boltzmann equation simplified by a collision model is solved by means of a finite difference approximation with the discrete ordinate method. Calculations are made for flows inside micro-channels of backward-facing step, forward-facing step, and slider bearings. The results are compared well with those from the DSMC method. The present method does not suffer from statistical noise which is common in particle based methods and requires less computational effort.

• 한국가축번식학회지
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• 제10권1호
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• pp.42-48
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• 1986

These experiments were carried out to develop new techniques identifying XX-bearing embryos prior to implantation by immunological method. Antiserum to histocompatibility-Y(H-Y) antigen was prepared in adult SD(sprague-dawley) female rat by repeated immunization of newbone testis supernatant from males of the same strain. ELISA test was used to identify the H-Y antibody of antiserum. Total 124 mouse embryos (8-cell stage) were treated with H-Y antiserum and complement in BSA free Ho, pp. and Pitt's medium and cultured under the gas phase of 5% CO2 in air at 37$^{\circ}C$ for 24 to 48 hrs. The morphological characteristics of embryos treated were observed under the phase-contrast micro scope. The results obtained in these experiments were summarized as follows: 1. Optimal Density of H-Y antibody were a, pp.ared to be 0.27-0.47 by ELISA test. 2. Of total 124 embryos treated with H-Y antiserum and complement 69(55.6%) embryos developed to blastocyst and 55(44.4%) destroyed or arrested.

• Carbon letters
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• 제8권1호
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• pp.17-24
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• 2007

Microporous carbons with narrow pore size distribution have been successfully synthesized by using hydrolyzed and calcined silica as templates and phenol formaldehyde (pf) resin as carbon precursor. Phenol formaldehyde-silica micro composites were prepared by solution route. Subsesequently, silica templates were removed by HF leaching. Resulting carbons were steam activated. The porous carbons were characterized by nitrogen adsorption-desorption isotherm, SEM, FTIR analysis, iodine adsorption, thermogravimetry analysis, etc. Adsorption isotherms show that the porous carbon prepared from calcined silica as templates are microporous with 88% pores of size <2 nm porosity and are of type I isotherm, while porous carbon prepared by using hydrolyzed silica are microporous with 89% microporosity, shows hysteresis loop at high relative pressure indicating the presence of some mesoporosity in samples. The microporosity in porous carbon materials has a bearing on the nature of silica templates used for pore formation.

• Asia Pacific Journal of Business Review
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• 제2권2호
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• pp.45-59
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• 2018

Globalization is swapping the every possible corner of the globe steadily yet gradually. Mammoth like companies are penetrating the threshold of potential nations as freelancers and exploiting every inch of feasibility to carry out commercial activities. Undoubtedly, the entire world is experiencing the glare of new horizon. Even laggards nations are also turning out to be a country of immense potential and dynamism. They too, have awakened miserably to comprehend their self worth and entity while bearing the torch of Globalization. The shed of globalization have not only sprinkled capitalistic or mercantilist but even countries like China - once a hardcore communist country is also not remaining untouched with it. Albeit, the Dragon responding affirmatively to the hot current of Globalization yet their way is un-orthodoxical, strange and inventive. This case study discussed on major areas where India, the largest democracy in the world and six largest economy in the world are facing steep competition from China.

• Smart Structures and Systems
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• 제1권2호
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• pp.159-184
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• 2005

The paper intends to summarize some guidelines for future smart structure system application in military aircraft. This preview of system integration is based upon a review on approximately one and a half decades of application oriented aerospace related smart structures research. Achievements in the area of structural health monitoring, adaptive shape, adaptive load bearing devices and active vibration control have been reached, potentials have been identified, several feasibility studies have been performed and some smart technologies have been already implemented. However the realization of anticipated visions and previously initial timescales announced have been rather too optimistic. The current development shall be based on a more realistic basis including more emphasis on fundamental aircraft strength, stiffness, static and dynamic load and stability requirements of aircraft and interdisciplinary integration requirements and improvements of integrated actors, actuator systems and control systems including micro controllers.

• 한국윤활학회:학술대회논문집
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• 한국윤활학회 2001년도 제33회 춘계학술대회 개최
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• pp.122-126
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• 2001

Magnetic hard disk drive is continually being pushed to reduce head-disk spacing for higher recording densities. The current minimum spacing between the air-bearing slider and disk has been reduced to under 15 nm. In this work, it was investigated if flying height could be lowered under the height of laser bumps. With the reduction of the spinning speed, the flying height was decreased under the height of laser bumps. When a head swept between landing zone and data zone, the head-disk impact was monitored using AE and friction signals. It is demonstrated that magnetic hard disk drive could be operated without tribological failures under the height of laser bumps.

• Mass Spectrometry Letters
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• 제4권3호
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• pp.51-54
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• 2013

Isotopic analysis using thermal ionization mass spectrometry coupled with scanning electron microscopy (SEM-TIMS) was performed to determine the isotopic ratios of uranium contained in micro-particles in the 6th Nuclear Signatures Interlaboratory Measurement Evaluation Programme (NUSIMEP-6) sample. Elemental analysis by energy dispersive X-ray spectroscopy (EDS) was conducted on uranium-bearing mirco-particles, which were transferred to rhenium filaments for TIMS loading using a micromanipulation system in a SEM. A multi-ion-counter system was utilized to detect the ion signals of the four isotopes of uranium simultaneously. The isotope ratios of uranium corrected by bracketing using a reference material showed excellent agreement with the certified values. The measurement accuracy for $n(^{234}U)/n(^{238}U)$ and (b) $n(^{235}U)/n(^{238}U)$ was 10% and 1%, respectively, which met the requirements for qalification for the NetWork of Analytical Laboratories (NWAL).

• 자원환경지질
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• 제55권6호
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• pp.597-616
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• 2022

The Chungnam basin is a crucial area for studying the Mesozoic crustal evolutionary history of the Korean Peninsula. This study reports the revised geology and new isotopic ages from the northeastern Chungnam Basin based on detailed geological mapping and LA-ICP-MS zircon U-Pb analysis. Our renewed geologic map defines intra-basin, basin-bounding, and basement fault systems closely related to hydrothermal gold-bearing quartz vein injections. Here, we propose the directions of (micro)structural and geochronological future work to address issues on the relationship between the tectonic process, basin evolution, and hydrothermal fluid migration in the southwestern Korean Peninsula.