• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2002.08a
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• pp.58-63
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• 2002

For the experiment the four types of spacer were distinguished by arrangement. The flashover characteristic on each types of spacer was investigated and the flashover phenomena were observed to understand breakdown mechanism in liquid nitrogen($LN_{2}$). The spacer should be placed interior coil as an insulator, a cooling channel and s supporter of structures. The simulated electrode used in the experiment was made from five turns of HTS tape. Experimental results revealed that multi-layer and barrier effects did work well in Air but did not in $LN_{2}$. These result suggested that the flashover in LN2 caused by the bubbles due to partial discharge at micro gap, g. The flashover characteristics decreased to 70% when g is 0.2 mm. The degradation was improved by even treatment on surface of coil electrode.

• Journal of Radiation Protection and Research
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• v.29 no.1
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• pp.41-48
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• 2004

A safety assessment code, called SAGE (Safety Assessment Groundwater Evaluation), has been developed to describe post-closure radionuclide releases and potential radiological doses for low- and intermediate-level radioactive waste (LILW) disposal in an engineered vault facility in Korea. The conceptual model implemented in the code is focused on the release of radionuclide from a gradually degrading engineered barrier system to an underlying unsaturated zone, thence to a saturated groundwater zone. The radionuclide transport equations are solved by spatially discretizing the disposal system into a series of compartments. Mass transfer between compartments is by diffusion/dispersion and advection. In all compartments, radionuclides ate decayed either as a single-member chain or as multi-member chains. The biosphere is represented as a set of steady-state, radionuclide-specific pathway dose conversion factors that are multiplied by the appropriate release rate from the far field for each pathway. The code has the capability to treat input parameters either deterministically or probabilistically. Parameter input is achieved through a user-friendly Graphical User Interface. An application is presented, which is compared against safety assessment results from the other computer codes, to benchmark the reliability of system-level conceptual modeling of the code.

• Journal of Korea Port Economic Association
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• v.17 no.2
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• pp.1-28
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• 2001

Korea has been at the forefront of efforts to enhance international cooperation in transport and communications within Northeast Asia. This effort is driven not only by the benefits that could accrue to the Korean Peninsula but also to all nations in the region. Mutual cooperation within Northeast Asia would reduce transport and communications costs and provide the basis for a regional transport and logistics network. Before progress can be made towards an integrated transport and communications system in Northeast Asia, however, there is a need to evaluate its prospects, outline a visionary plan, and detail a preferred strategy. The strategy to develop the Korean Peninsula as the gateway for Northeast Asia should harmonize with the region's common transport (and communications) policy The strategy adopted by South Korea is focused primarily on the development of an improved logistics infrastructure that would be extended to North Korea upon reunification. The seaport and airport developments In Korea will have to be supported by improved access to planned high-speed railways, expressways and freight distribution centers that, in turn, are to be integrated with new telecommunications and computer technologies. The benefits from these improvements will be lost unless existing government monopolies controlling seaport, airport, rail, road and expressway developments are commercialized to ensure that the price of transport reflects its actual cost. Technical harmonization between different modes should be promoted to facilitate efficient intermodal transport between the Korean Peninsula and the rest of Northeast Asia.

• Proceedings of the SAREK Conference
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• 2006.06a
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• pp.953-958
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• 2006

Perimeter zone has been reinforced by active systems, such as fan-coil units, because it causes an increase in heating and cooling loads, dew condensation in winter, or discomfort with cold-draft to residents in buildings, through poor insulation by light-weighed skin due to progressing multi-storied buildings and skyscrapers. However, because these active systems raise Its capacity so that fossil fuel is used as much as they are added, and ultimately, greenhouse effect is urged, we proposed BIPV system functioned as solar collector which can substitute active system. As an early stage, heat balance equation in steady-state by Fortran was used not only for pre-heating effect and electric power capacity during the day in winter, but also for electric power capacity during day in slimmer and sky radiation effect during night in summer. Especially, we should have considered shading on PV, since even a little bit of it makes the efficiency too low for the PV to work. Still, when the flux of pre-heated air was increased to make air-barrier, its temperature was not enough to make it because the speed of heat exchange was too fast to warm up the air, thus the capacity to meet the condition was evaluated, and electric power from PV was made used for it.

• Journal of Surface Science and Engineering
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• v.55 no.6
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• pp.398-402
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• 2022

Vacuum Insulation Panel (VIP) is an high energy efficient insulation system that facilitate slim but high insulation performance, based on based on a porous core material evacuated and encapsulated in a multi-barrier envelope. Although VIP has been on the market for decades now, it wasn't until recently that efforts have been initiated to propose a standard on aging testing. One of the issues regarding VIP is its durability and aging due to pressure and moisture dependent increase of the initial low thermal conductivity with time. It is hard to visually determine at an early stage. Recently, a method of analyzing the damage on the a material surface by applying image processing technology has been widely used. These techniques provide fast and accurate data with a non-destructive way. In this study, the surface VIP images were analyzed using the Harris corner detection algorithm. As a result, 171,333 corner points in the normal packaging were detected, whereas 32,895 of the defective packaging, which were less than the normal packaging. were detected. These results are considered to provide meaningful information for the determination of VIP condition.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.37 no.1
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• pp.88-93
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• 2024

To evaluate the possibility as a multi-level memory medium for the Ge₂Sb₂Te₅/TiN/W-doped Ge₂Sb₂Te₅ cell structure, the crystallization rate and stabilization characteristics according to voltage (V)- and current (I)- pulse sweeping were investigated. In the cell structures prepared by a magnetron sputtering system on a p-type Si (100) substrate, the Ge₂Sb₂Te₅ and W-doped Ge₂Sb₂Te₅ thin films were separated by a barrier metal, TiN, and the individual thicknesses were varied, but the total thickness was fixed at 200 nm. All cell structures exhibited relatively stable multi-level states of high-middle-low resistance (HR-MR-LR), which guarantee the reliability of the multilevel phase-change random access memory (PRAM). The amorphousto-multilevel crystallization rate was evaluated from a graph of resistance (R) vs. pulse duration (T) obtained by the nanoscaled pulse sweeping at a fixed applied voltage (12 V). For all structures, the phase-change rates of HR→MR and MR→LR were estimated to be approximately t<20 ns and t<40 ns, respectively, and the states were relatively stable. We believe that the doublestack structure of an appropriate Ge-Sb-Te film separated by barrier metal (TiN) can be optimized for high-speed and stable multilevel PRAM.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2008.11a
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• pp.259-259
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• 2008

The LTCC (Low Temperature Co-fired Ceramic) technology meets the requirements for high quality microelectronic devices and microsystems application due to a very good electrical and mechanical properties, high reliability and stability as well as possibility of making integrated three dimensional microstructures. The wet process, which has been applied to the etching of the metallic thin film on the ceramic substrate, has multi process steps such as lithography and development and uses very toxic chemicals arising the environmental problems. The other side, Plasma technology like ion beam sputtering is clean process including surface cleaning and treatment, sputtering and etching of semiconductor devices, and environmental cleanup. In this study, metallic multilayer pattern was fabricated by the ion beam etching of Ti/Pd/Cu without the lithography. In the experiment, Alumina and LTCC were used as the substrate and Ti/Pd/Cu metallic multilayer was deposited by the DC-magnetron sputtering system. After the formation of Cu/Ni/Au multilayer pattern made by the photolithography and electroplating process, the Ti/Pd/Cu multilayer was dry-etched by using the low energy-high current ion-beam etching process. Because the electroplated Au layer was the masking barrier of the etching of Ti/Pd/Cu multilayer, the additional lithography was not necessary for the etching process. Xenon ion beam which having the high sputtering yield was irradiated and was used with various ion energy and current. The metallic pattern after the etching was optically examined and analyzed. The rate and phenomenon of the etching on each metallic layer were investigated with the diverse process condition such as ion-beam acceleration energy, current density, and etching time.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.25 no.1
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• pp.44-47
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• 2012

The $TiO_2/Si_3N_4/Ag/Si_3N_4/TiO_2$ multi layered structure was designed for the possible application of transparent electrodes in PDP (Plasma Display Panel). Multi layered film was deposited on a glass substrate at room temperature by DC/RF magnetron sputtering system and EMP (Essential Macleod Program) was adopted to optimize the optical characteristics of film. During the deposition process, the Ag layer in $TiO_2/Ag/TiO_2$ became heavily oxidized and the filter characteristic was degraded easily. In thus study, Si3N4 layer was used as a diffusion buffer layer between $TiO_2$ and Ag. in order to prevent the oxidation of Ag layer in $TiO_2/Si_3N_4/Ag/Si_3N_4/TiO_2$ structure. It was confirmed that $Si_3N_4$ layer is one of candidate materials acting as diffusin barrier between $TiO_2/Ag/TiO_2$.

• Journal of Home Health Care Nursing
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• v.25 no.2
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• pp.127-138
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• 2018

Purpose: This study aimed to provide an overview of the present status of start-up literacy. Methods: The study selected literature from KoreaMed, RISS (Research Information Sharing Service), KISS (Korean studies Information Service System), KISTI (Korea Institute of Science and Technology Information), Ovid-MEDLINE (Medical Literature Analysis and Retrieval System Online), Embase, and Cochrane Library DB. Start-up curricula were collected from the homepage of nursing schools in Korea and the USA. Their contents were searched using Massive Open Online Course (MOOC) platforms; KOCW, K-MOOC, and Coursera. Results: Fifteen articles were selected through a systematic literature review. The main themes of nursing start-up were "driver," "barrier," "required competency," and "importance of education." The courses contained business planning, finance, marketing, leadership, and entrepreneurship. The main contents of MOOCs were similar. Conclusion: The results indicate the necessity to develop multi-scope nursing start-up education programs. Nursing start-up models integrated with appropriate business knowledge and skills in health care settings are needed. This study can be used as a guideline to design start-up education programs in nursing.

• Journal of the Korean Institute of Gas
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• v.25 no.5
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• pp.70-77
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• 2021

As IoT technology develops along with the 4th industrial revolution, gas safety products to which IoT technology is applied are being developed. However, since the gas safety system was not allowed, system improvement and operation reliability test for IoT gas safety products are required. This thesis researches IoT fuse cock and smart multi-function meter among IoT gas safety products, and analyzes the empirical data of IoT fuse cock to secure operational reliability data, thereby becoming a leader in IoT gas safety products. It aims to develop gas barrier technology one step further through various test evaluations and methods in the future.