• Journal of Radiation Protection and Research
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• v.20 no.3
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• pp.143-154
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• 1995

In recent years, the development of new technologies using static magnetic fields has increased the possibility of human exposure to these fields and raised some concern as to their possible health effects. In several countries, governmental or other competent authorities have issued exposure limits that are mainly intended for specific uses, i.e., magnetic resonance imaging (MRI) and particle accelerators for high-energy Physics. Since applications of magnetic fields in industry and medicine are likely to grow in the future, thus increasing the possibility of occupational and general public exposure, and since the number of people with ferromagnetic implants and implanted electronic devices that can be affected by the fields is growing, there is a need for international guidelines. In the present papers, guidelines on limits of exposure to static magnetic fields are selected and discussed in order to review the guidelines of the International Non-ionizing Radiation Committee of the International Radiation Protection Association (IRPA/INIRC) for non-ionizing radiation(NIR)

• The Journal of the Korea institute of electronic communication sciences
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• v.11 no.10
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• pp.983-988
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• 2016

Internet of Things Iranian people and things, things and things are connected through the Cloud. It can significantly save energy through a combination of LED lighting as a new ICT technologies and industry-to provide a human-centric, eco-friendly, and the content is embedded multifunction solutions that meet your needs, environment, implementation time according to user requirements, technology It can be systematized as converged next-generation lighting. In this paper, we have developed regarding whether the building in relation to the LED lighting control system using smart devices and Cloud-based user as a human connection through the board to the Arduino Yun lit LED lighting, wireless smart device or to the Cloud or off. After the Arduino Yun is connected to the Internet, taking the current date and time information from the Linux shell command used the way coming across the bridge (BRIDGE) its value.

• Journal of the Korean Applied Science and Technology
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• v.29 no.1
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• pp.19-32
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• 2012

Pharmaceutical use accounts for a great part of articles and papers on crosslinking of polymers. Crosslinking of polymers used for tissue engineering and drug delivery respects non-cytotoxicity and in situ gelling. The crosslinking of polymers is aimed not only at the improvement of modulus, chemical resistance, and thermal resistance, but also at endowing them with such functions as metal adsorption, antifouling, and ion exchange via crosslinked segments. Smart polymers responding to environmental change, and cosslinking mediated by light, enzyme, natural compound and in aqueous medium in consideration of environment are being studied. Developing new polymeric materials is essential along with the pharmaceutics aiming at the longevity of 120 years old. Functionalization and property adjustment of polymers through crosslinking will be done more delicately. Hydrogels will be focused on injectable and in situ gel forming. In the coating industry crosslinking system with low non-toxicity and low energy consumption will be developed in consideration of workers and environment.

• Journal of Advanced Marine Engineering and Technology
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• v.38 no.5
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• pp.589-601
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• 2014

Natural gas hydrate (NGH) is emerging as a new eco-friendly source of energy to replace fossil fuels in the 21st century. It is well known that the Natural Gas Hydrate contains large amount of natural gas about 170 times as much as its volume and it is easy to be stored and transported safely at about $-20^{\circ}C$ under atmospheric pressure due to so called "self-preservation effect". The option of gas transport by gas hydrate pellets carrier has been investigated and developed in various industry and academy. The natural gas hydrate pellet carrier is on major link in a potential gas hydrate process chain, starting with the extraction of natural gas from the reservoir, followed by the production of hydrate pellets and the transportation to an onshore terminal for further processing or marketing. In recent years, Korean project team supported by Korean Government has been working on the development of NGH total systems including novel NGH carrier since 2011. In order to increase the knowledge on the NGH pellet carrier developed and to understand the major hazards that could have significant impact on the safety of the vessel, this paper presents and evaluates the pros and cons of cargo holds, loading and unloading systems through the analysis of current patent technology. Based on the proven and well-known technologies as well as potential measures to mitigate sintering and minimize mechanical stress on the hydrate pellet in the self-preservation state, this study presents the conceptual and basic design for NGH carrier.

• Journal of the Korean Society for Heat Treatment
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• v.24 no.1
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• pp.31-36
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• 2011

$TiO_2$ films were deposited on a glass substrate with RF magnetron sputtering and then surface of $TiO_2$ films were electron beam irradiated in a vacuum condition to investigate the effect of electron bombardment on the thin film crystallization, surface roughness and gas sensitivity for hydrogen. $TiO_2$ films that electron beam irradiated at 450eV were amorphous phase, while the films irradiated at 900 eV show the anatase (101) diffraction peak in XRD pattern. AFM measurements show that the roughness is depend on the electron irradiation energy. As increase the hydrogen gas concentration and operation temperature, the gas sensitivity of $TiO_2$ and $TiO_2$/ZnO films is increased proportionally and $TiO_2$ films that electron beam irradiated at 900 eV show the higher sensitivity than the films were irradiated at 450eV. From the XRD pattern and AFM observation, it is supposed that the crystallization and rough surface promote the hydrogen gas sensitivity of $TiO_2$ films.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.34 no.1B
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• pp.10-15
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• 2009

Recently, there are tendency that wireless sensor network is one of the important techniques for the future IT industry and thereby application areas in it are getting growing. Researches based on the hierarchical network topology are evaluated in good at energy efficiency in related protocols for wireless sensor network. LEACH is the best well known routing protocol for the hierarchical topology. However, there are problems in the range of message broadcasting, which should be expand into the overall network coverage, in LEACH related protocols. Thereby, this paper proposes a new clustering scheme to solve the co-shared problems in them. The basic idea of our scheme is using the inherent memory restrictions in sensor nodes. The results show that the proposed scheme could support the load balancing by distributing the clusters with a reasonable number of member nodes and thereby the network life time would be extended in about 1.8 times longer than LEACH.

• The KSFM Journal of Fluid Machinery
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• v.18 no.3
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• pp.46-52
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• 2015

Pump-turbine system is widely used by the hydropower industry for stabilizing the electrical grid in the vast growing economy of most developed countries. This study only investigates the Fluid-structure Interaction (FSI) analysis of the pump-turbine system at various operating conditions. The FSI analysis can show how reliable each component of the system is by providing the engineer with a better understanding of high stress and deformation points, which could reduce the lifespan of the pump-turbine. Pump-turbine components are categorized in two parts, pressurized static parts and movable stressed parts. The fixed parts include the spiral casing, top and bottom cover, stay vane and draft tube. The movable parts include guide vanes and impeller blades. Fine hexahedral numerical grids were used for CFD calculation and fine tetrahedral grids were used for structural analysis with imported load solution mapping greater than 90 %. The maximum equivalent stress are much smaller than the material yield stress, and the maximum equivalent stress showed an increasing tendency with the varying of operating conditions from partial to excessive at both modes. In addition, the total deformation of all the operating conditions showed a small magnitude, which have quite small influence on the structural stability. It can be conjectured that this system can be safely implemented.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.40 no.2
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• pp.104-110
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• 2017

When evaluating effectiveness of a R&D program, there is a tendency to simply compare the performances of the beneficiaries before and after the program or to compare the differences in the performances of the beneficiaries and the non-beneficiaries before-after the program. However, these ways of evaluating effectiveness of a program have some problems because they can not differentiate between complement effect, which facilitates corporate R&D investment, and substitute effect, which, literally, substitutes corporate R&D investment. Therefore, these problems could bring about wrong policies concerning R&D programs. In this paper, a new approach using path analysis is suggested as a means to overcome these problems and it is utilized, as an application, to evaluate the effectiveness of Plant Engineering Program conducted by Ministry of Trade, Industry & Energy, Korea. First, the direct impact of government R&D investment on corporate R&D investment is analyzed, through which it is identified which of crowding-in effect (complement effect) and crowding-out effect (substitute effect) is dominant. Next, the direct effect of government R&D investment on corporate performance and the direct effect of corporate R&D investment on corporate performance is analyzed respectively. Finally, by combining the two previous analysis, the total effect of government R&D investment on corporate performance is identified. As a result, it turns out that, in Plant Engineering Program, crowding-in effect is more dominant than crowding-out effect and that Plant Engineering Program has definitely positive effect on the beneficiary in terms of corporate performance indirectly and directly.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.43 no.3
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• pp.101-111
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• 2020

Companies struggle to make their best products with high quality and service at a competitive price in global markets. However, customer needs and requirements keep changing with a variety of situations. Companies that face the changes can not stay the same and make an effort to adapt themselves to new circumstances. They would probably review the overall management system that is currently implementing to improve management efficiency. Among other things, quality might be considered to be a crucial element if they are manufacturing industries to be sustained in global markets. KSA (Korean Standards Association) is a government-affiliated organization under the Ministry of Trade, Infrastructure, and Energy. It is a Korean standards provider for quality and service industry. KSA confers national commendations for organizations, quality circles, artisans, QCEC (Quality Competitive Excellent Company), and the most honorable KNQA (Korean National Quality Award) every year. KSA established KNQA on the basis of Malcom Baldrige National Quality Award, Deming Prize, and European Quality Award. Research on quality awards shows that there are many similarities in the framework. Although KSA summarizes two factors for 13 evaluation indicators in the quality competitive excellent model of QCEC, the categorization is ambiguous to explain them according to earlier studies. We performed a deep analysis of foreign quality awards and background for KNQA and QCEC. We conducted a content analysis of KNQA and QCEC and matched evaluation items that were closely related. We proposed a quality competitiveness model with three factors, Technology, System, and Tools, summarizing 13 evaluation indicators in QCEC. Based on audit data for six years from 2012 to 2017 we carried out a confirmatory factor analysis for the proposed model by examining the model validity and fitness.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2004.03a
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• pp.593-596
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• 2004

We are developing a micro-solid propellant rocket array thruster for simple attitude control of a 10 kg class micro-spacecraft. The prototype has ø 0.8 mm solid propellant micro-rockets arrayed at a pitch of 1.2 mm on a 22 x 22 mm substrate. In previous studies, an impulse thrust of 4.6 x 10$^{-4}$ Ns was obtained in vacuum, but we found the problems of unacceptably low ignition success rate and incomplete combustion. This paper describes experiments to improve the ignition rate. In order to achieve this goal, we tried to solidify paste-like ignition aid (RK) on the ignition heaters with strong adhesion. To make the paste-like RK, isoamyl acetate was added to RK powder. We tested 9 rockets, but only 2 rockets were ignited with huge ignition energy. This is because the heat con-duction between the ignition heater and the RK was too low to ignite the RK, since dried RK had a lot of pores. Also, a large cavity was sometimes found just above the ignition heater.