• Transactions of the Korean Society of Mechanical Engineers A
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• v.41 no.5
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• pp.361-366
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• 2017

As the recent development of computing architecture and application software technology, real world simulation, which is the ultimate destination of computer simulation, is emerging as a practical issue in several research sectors. In this paper, metal plate motion in a square shock tube for small time interval was calculated using a supercomputing-based fluid-structure-combustion multi-physics simulation tool called Illinois Rocstar, developed in a US national R amp; D program at the University of Illinois. Afterwards, the simulation results were compared with those from experiments. The coupled solvers for unsteady compressible fluid dynamics and for structural analysis were based on the finite volume structured grid system and the large deformation linear elastic model, respectively. In addition, a strong correlation between calculation and experiment was shown, probably because of the predictor-corrector time-integration scheme framework. In the future, additional validation studies and code improvements for higher accuracy will be conducted to obtain a reliable open-source software research tool.

• Proceedings of the Korea Association of Crystal Growth Conference
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• 1996.06a
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• pp.508-508
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• 1996

;The growth of films have considerable interest in the field of superlattice structured multi-layer epitaxy led to realization of new devices concepts. Molecular beam epitaxy (MBE) with in situ observation by reflection high-energy electron diffraction (RHEED) is a key technology for controlled layered growth on the atomic scale in oxide crystal thin films. Also, the combination of radical oxygen source and MBE will certainly accelerate the progress of applications of oxides. In this study, the growth process of single crystal films using by MBE method is discussed taking the oxide materials of Bi-Sr-Ca-Cu family. Oxidation was provided by a flux density of activated oxygen (oxygen radicals) from an rf-excited discharge. Generation of oxygen radicals is obtained in a specially designed radical sources with different types (coil and electrode types). Molecular oxygen was introduced into a quartz tube through a variable leak valve with mass flowmeter. Corresponding to the oxygen flow rate, the pressure of the system ranged from $1{\;}{\times}{\;}10^{-6}{\;}Torr{\;}to{\;}5{\;}{\times}{\;}10^{-5}$ Torr. The base pressure was $1{\;}{\times}{\;}10^{-10}$ Torr. The growth of Bi-oxides was achieved by coevaporation of metal elements and oxygen. In this way a Bi-oxide multilayer structure was prepared on a basal-plane MgO or $SrTiO_3$ substrate. The grown films compiled using RHEED patterns during and after the growth. Futher, the exact observation of oxygen radicals with MBE is an important technology for a approach of growth conditions on stoichiometry and perfection on the atomic scale in oxide. The oxidization degree, which is determined and controlled by the number of activated oxygen when using radical sources of two types, are utilized by voltage locked loop (VLL) method. Coil type is suitable for oxygen radical source than electrode type. The relationship between the flux of oxygen radical and the rf power or oxygen partial pressure estimated. The flux of radicals increases as the rf power increases, and indicates to the frequency change having the the value of about $2{\times}10^{14}{\;}atoms{\;}{\cdots}{\;}cm^{-2}{\;}{\cdots}{\;}S^{-I}$ when the oxygen flow rate of 2.0 seem and rf power 150 W.150 W.

• Membrane Journal
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• v.16 no.2
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• pp.159-166
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• 2006

MFI(Mobil Five) structured hydrophobic ZSM-5 zeolite membrane was used for selective pervaporation of trichlorinated organic compounds(trichloromethane, trichloroethane, trichloroethylene) from their aqueous solutions. ZSM-5 zeolite membrane was hydrothermally synthesized on the inside of a porous stainless steel tube by secondary growth employing ZSM-5 seed powders. Separation factors for each binary mixtures were observed $16{\sim}66$ for trichloromethane/water, $3.3{\sim}4.6$ for trichloroethane/water and $1.4{\sim}8$ for trichloroethylene/water at the experimental conditions of the feed mole fraction from 0.0001 to 0.001 with temperature ranged $25{\sim}35^{\circ}C$.

• International Journal of Knowledge Content Development & Technology
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• v.14 no.3
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• pp.59-76
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• 2024

The prominent role accorded to social media in the academic community for research, teaching and learning revolves around its significance among users. Social media offers a platform for individuals to engage with and share perceptions relating to different disciplines. This current research was conducted to investigate the level of awareness and frequency of social media technology use among postgraduate students of Library and Information Science in Nigerian universities. The descriptive survey design was used for the study. Structured questionnaires were used to collect data from 919 library and information science (LIS) postgraduate students in the universities. In all, 742 copies out of the 919 distributed were returned and found usable, thereby making the return rate to be 81%. Data collected were analysed using mean and standard deviation. The study revealed that the LIS postgraduate students frequently use social media such as Wikipedia (x=3.94>3.50), Instagram (x=3.86>3.50), Facebook (x=3.85>3.50), Zoom ($\overline{x}$=3.78>3.50), LinkedIn (x=3.69>3.50), YouTube ($\overline{x}$=3.54>3.50), Twitter (x=3.52>3.50). The study established that students use social media tools for their personal, professional and research activities. The study also found that the level of awareness and use of social media by the students was high. The study recommended that the use of social media should be incorporated into the LIS curriculum including training sessions for the students on how to use the media effectively.

• The Journal of the Korea Contents Association
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• v.14 no.5
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• pp.211-223
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• 2014

The aim of this study was to identify the levels of family members' burden and to describe factors influencing on famiCX*//8ly caregiver's burden when they are planned to transfer to general ward from the intensive care units (ICU). A descriptive survey was used with a convenience sampling of 101 family members of ICU patients at S university hospital in C city, Korea from August to November, 2010. The data were analyzed with SPSS 18.0 program. The level of object burden in family members had statistically significant differences with level of consciousness, number of patients' monitoring devices, and tracheostomy tube. The level of subject burden had statistically significant differences according to patients' gender, patients' education level, and relationship with patients. Transfer anxiety was showed statistically positive correlation with objective and subjective burden. We found transfer anxiety was statistically significant predictor of family caregiver's objective burden with explanatory power 12.7%. Family members' subjective burden were statistically influenced by patients' gender and transfer anxiety. These factors explained 23.8% out of total variance of family members' objective burden. The structured individualized method of transfer is recommended with further research of ICU families to further examine the dimension of transfer anxiety and how it affects family members' burden and patient outcomes.