• International Journal of Aeronautical and Space Sciences
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• v.14 no.2
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• pp.105-111
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• 2013

Radiative heating phenomena occurring in planetary entry flights are reviewed for the purpose of educating those who are not familiar with the problem. How the radiative heat transfer rates to the Apollo entry vehicle were measured and analyzed are first described. Next, the effects of thermo-chemical non-equilibrium on radiation are summarized. Then the radiation problems in entry flights into other planets are reviewed. Finally, unsolved problems are enumerated.

• Journal of Korea Technology Innovation Society
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• v.16 no.3
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• pp.605-629
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• 2013

The aim of this study is analyzing the factors and performance related to the entry control mode when a SME advances into the global market. For this, the strategic factor of the SME was divided into the enterprise capabilities consisting of technology commercial capability, internal capability, and global capability of enterprise and information capabilities that are the capabilities on the global market and on the advanced technology. In the empirical study, a total of 27 variables that include the control variables and the financial and non-financial variables as a performance variable was used. The hypothesis was also established for analyzing the effect of the entry strategies on the entry control mode and the effect of the mode on performance. Logistic regression was conducted for verifying the hypothesis, and Multiple regression analysis and T-test were carried out on the additional analysis related to the performance.

• International Journal of Aeronautical and Space Sciences
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• v.12 no.3
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• pp.211-224
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• 2011

This is a written version of an hour-long lecture delivered by the author on June 30, 2011, as Plasmadynamics and Lasers Award Lecture at the AIAA 2011 summer conference in Honolulu, Hawaii. The author proposes that two areas of planetary entry physics be pursued in the future: outer planet aero-capturing and study of aerodynamics of meteoroid entries, both for the purpose of advancing the understanding of the possible extraterrestrial seeding of building blocks of life. For outer planet aero-capturing, the author proposes to develop new shock tube facilities that will produce up to 30 km/s of shock speed without causing photo-ionization of the driven gas by the radiation from the hot driver gas. Regarding meteors, the author proposes to carry out laboratory testing of the Tunguska event and of the seeding of amino acid molecules using a ballistic range which shoots a snowball laden with amino acid molecules toward a water surface.

• Nuclear Engineering and Technology
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• v.53 no.4
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• pp.1318-1322
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• 2021

To unveil and delineate the elements applicable to the radiation protection of a femoral entry shield, calculate its mass attenuation coefficient, and demonstrate its dose reduction efficacy for interventional radiologist performing transarterial embolization (TAE) of ruptured hepatocellular carcinoma (rHCC). The lead equivalency of the shield was firstly validated. Electron microscopy was used to confirm the femoral entry shield being lead-free and to analyze the elemental content, with which the mass attenuation coefficient of the shield was calculated. An adult phantom, irradiated at the upper abdomen to simulate the TAE of rHCC, was used together with a dosimeter attached to the palm of a hand phantom. The dose rates at the hand phantom were measured, with the rHCC clinical protocol, without and with the femoral entry shield placed over the right femoral access site of the adult phantom. Without using the shield, the average hand dose rate was measured to be 0.325 µSv/sec. While using the shield, it was determined to be 0.110 µSv/sec. There was significant 66% dose reduction to the hand dose of IRs performing angiographic intervention with the femoral entry shield.

• Proceedings of the Korean Biophysical Society Conference
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• 1999.06a
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• pp.67-67
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• 1999

The effect of chlorpromazine on the store-operated Ca$\^$2＋/ entry subsequently activated via the phospholipase C signaling pathway was investigated in PC12 cells. Chlorpromazine caused a rapid decline of the bradykinin-induced Ca$\^$2＋/ increase to basal level without attenuating the peak level.(omitted)

• International conference on construction engineering and project management
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• 2009.05a
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• pp.1388-1395
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• 2009

In March 2007, Korea's Ministry of Construction & Transportation (MOCT) established "Guidelines on the Computerization and Use of Geotechnical Investigation Results," which took effect as official instructions. The 2007 Geotechnical Information DB Construction Project is underway as a model project for a stable geotechnical information distribution system based on the MOCT guidelines, accompanied by user education on the geotechnical data distribution system. This study introduces a geotechnical data entry system characterized by the standardization of the geotechnical investigation form, the standardization of metadata for creating the geotechnical data to be distributed, and the creation of borehole space data based on the world geodetic system according to the changes in the national coordinate system, to define a unified DB structure and the items for the geotechnical data entry system and to computerize the field geotechnical investigation results using the MOCT guidelines. In addition, the present operating status of the geotechnical data entry system and entry data processing statistics are introduced through an analysis of the model project, and the problems of the project are analyzed to suggest improvements. Education on, and the implementation of, the model project for the geotechnical data entry system, which was developed via the standardization of the geotechnical investigation results form and the metadata for institutions showed that most users can use the system easily. There were problems, however, including those related to the complexity of metadata creation, partial errors in moving to the borehole data window, partial recognition errors in the installation program for different computer operating systems, etc. Especially, the individual standard form usage and the specificity of the person who enters the geotechnical information for the Korea National Housing Corporation, among the institutions under MOCT, required partial improvement of the geotechnical data entry system. The problems surfaced from this study will be promptly addressed in the operation and management of the geotechnical data DB center in 2008.

• Journal of Advanced Navigation Technology
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• v.19 no.5
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• pp.452-457
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• 2015

Recently, wearable devices have gained popularity with familiar form factors and designs of eye-wear and watch to satisfy wearers' various preferences. Since UI/UX of smartphones can not be applied directly on smaller wearable devices, text entry on wearable devices is still problematic. In this paper, we first identify UI/UX problems of existing input methods and propose a new input method for wearable devices specifically targeting smartwatch platforms. We design and implement an efficient text entry method for wearable devices using trackball sensor and evaluate its performance and usability.

• Journal of Information Technology Services
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• v.19 no.5
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• pp.49-64
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• 2020

Overseas expansion by small and medium-sized enterprises of the Korean software industry has been sluggish, with many SMEs lacking the necessary capabilities required for successful entry into the overseas markets. This study aims to identify the capabilities SMEs require to advance into overseas markets and develop a diagnosis model for evaluating overseas entry capability appropriate to the characteristics of SMEs. A basic research was first performed to gain a comprehensive understanding of the characteristics of the software industry, software exports, and SMEs. Based on this research, the study aimed to develop a model for diagnosing overseas entry capability of SMEs by dividing the required overseas entry capability into globalization capability in product area and internal competence from a resource-based perspective. In addition, This study aims to contribute to the success of SMEs in overseas markets by presenting a diagnosis model that evaluates the capabilities required to advance into overseas markets.

• Korean Journal of Metals and Materials
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• v.50 no.2
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• pp.129-135
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• 2012

High speed casting technology is an attractive method to increase the productivity of continuous casting. However, high speed casting causes flow instability of molten steel in a mold. In this study, Large Eddy Simulation (LES) has been performed to identify the characteristics of mold flow for various shapes of submerged entry nozzles. The LES code has been newly developed to efficiently compute the two-phase flow by using the Fractional Step Method (FSM) combined with the Volume of Fluid (VOF) method. The Immersed Boundary Method was used to implement the shape of the submerged entry nozzle. Three cases of discharge angle of the submerged entry nozzle were computed and compared. The current results shed light on improving shape design of a submerged entry nozzle.

• Research in Mathematical Education
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• v.16 no.1
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• pp.51-66
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• 2012

This study investigated the impact of entry level of mathematics subject knowledge on student teachers' mathematics pedagogical content knowledge development and performance in mathematics teaching practice. The sample consisted of 24 mathematics student teachers, 12 of whom passed A-Level mathematics and 12 of whom only passed O-level mathematics. They were all studying in a 4-year bachelor of education (Honours/Primary) programme; they were either majoring or minoring in mathematics. Results showed that student teachers' entry-level mathematics subject knowledge is not related to their mathematics pedagogical content knowledge development or their mathematics teaching performance. These findings may lead society to consider whether student teachers who have passed O-level mathematics are already eligible to be trained as professional primary mathematics teachers. As a consequence, this study raises the issues of how to develop student teachers' mathematics pedagogical content knowledge and whether we need to restructure our bachelor of education (Primary) programmes' curriculum in teacher professionalism.