• 방사선산업학회지
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• 제7권2_3호
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• pp.177-182
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• 2013

This study was conducted to evaluate the effect of gamma irradiation on the microbial populations of dried raw materials (9 products) and Saengsik powder. The samples were gammairradiated at doses of 2, 4, 6 and 8 kGy and the microbiological populations were evaluated. The total numbers of bacteria and Bacillus cereus in non-irradiated dried-raw materials for Saengsik powder was 1.3~3.4 and $1.7{\sim}2.4log\;CFU\;g^{-1}$. However, gamma irradiation reduced the microbiological populations in all samples, and Saengsik powder were sterilized at more than 6 kGy. Moreover, Clostridium perfringens were not observed in all samples within detection limit (<$1log\;CFU\;g^{-1}$). Therefore, the results of this study suggest that gamma irradiation at 6 kGy is sufficient to sterilize Saengsik powder, and thus, irradiated Saengsik powder at 6 kGy fulfills the microbiological requirements for sterilized food.

• Elastomers and Composites
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• 제52권1호
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• pp.22-26
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• 2017

The thermal conductivity and the adhesive properties were measured, after synthesis of thermal conductive composite which was obtained as a result of mixing alumina or graphite with acrylic adhesive synthesized by UV polymerization. The adhesive properties of the composite were evaluated measuring the peel strength at 180 degrees, the retention, and the initial tack;the thermal conductivity was estimated using laser flash analysis. As the filler contents increased, a decrease in peel strength and initial tack and an increase in retention and thermal conductivity were observed. When compared to alumina, the adhesion of graphite showed a dramatic decrease, whereas the thermal conductivity was further enhanced. It was found out that the small size of graphite increased the mechanical interlocking between the polymer and the filler, and it was easier for graphite to come into contact with other graphite in the matrix.

• 한국식품과학회지
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• 제50권3호
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• pp.249-259
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• 2018

Radiation technology (RT) has long been applied in various fields for increasing the safety and shelf-life of foods by controlling pathogen-induced poisoning. RT was introduced for the first time in Korea in the 1950s to eliminate harmful microorganisms in food materials. In the 1980s, RT had been scientifically proven to be effective for the sterilization of food and public health products. In recent years, irradiation with gamma rays has also been used for improving physiological properties through the structural modification of natural molecules, which has been proposed to be applicable to various industries. In particular, radiation transformation technology (RTT), which involves the development of new functional compounds through the molecular conversion of natural biomaterials, is becoming a new high-value technology as a fusion technique of RT and biotechnology. The present reports have suggested that RTT can be an effective tool for the development of new functional compounds and improvement of the physiological activity of biomolecules.

• Current Photovoltaic Research
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• 제12권2호
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• pp.37-40
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• 2024

One of the current innovation trends in the solar industry is the increase in the size of silicon wafers. As the wafer size increases, the series resistance of the module rises, highlighting the need for research on methods for cutting and bonding solar cells. Among these, the Infrared (IR) laser scribing technique has been extensively researched. However, there is still insufficient optimization research regarding the thermal damage caused by lasers on the Transparent Conductive Oxide (TCO) layer of Heterojunction (HJT) solar cells. Therefore, in this study, we systematically varied conditions such as IR laser scribing speed, frequency, power, and the number of scribes to investigate their impact on the performance of cut cells under each condition. Additionally, we conducted a comparative analysis of thermal damage effects on the TCO layer based on varying scribing depths.

• Journal of Information Technology Applications and Management
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• 제21권4호
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• pp.65-96
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• 2014

To have global competitiveness in newly growing industry, good quality R&D's in convergence technology arerequired. Korean government also started to emphasize the importance of convergence technology as a new engine of growth for the future development. Since 2008, worldwide energy crisis and concerns on low carbon green growth made people focus on the convergence between information technology (IT) and energy technology (ET). However, the R&D performance comparison among the convergence technologies is not well explored so far. Therefore, this study uses Korea's patent citation database to measure the R&D performance of convergence technologies. We adopt technology development cycle, technology spillover analysis, and technology diffusion analysis to see the knowledge flow from R&D industry to others. We find that IT_ET convergence technology generally shows higher R&D performance than other convergence technologies. Contrary to public belief, convergence R&D by big companies has relatively low performance especially measures in technology spillover and technology diffusion. This implies that they might concentrate on delicate Fuel Cell Energy/Environment Technology (FEIT) or Nano Environment/Energy Information Technology (NEIT) rather than general energy information technologies. We also find that Korea's chemical industry may play a crucial role for the growth of other convergence technologies.

• Nuclear Engineering and Technology
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• 제41권3호
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• pp.215-224
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• 2009

Innovative Human System Interfaces (HSIs) has been a major topic of research of the international Halden Reactor Project (HRP) for many years. Different design concepts have been addressed and prototypes have been implemented and evaluated in the experimental control room facility of HRP. Many of the concepts go far beyond traditional P&ID type displays, and utilize advanced computer graphics and animations. The paper briefly describes some of the concepts, their advantages and disadvantages experienced through evaluations and feedback from users.

• 신재생에너지
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• 제4권1호
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• pp.25-30
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• 2008

The R&D budget of energy technology development has increased in the sector of korean energy technology development continuously. In addition to that, KIER, the government invested research institute and unique energy technology R&D research institute, is trying to plan for a big-sized energy R&D program for the well focused R&D and excellent research outcomes. In the phase of R&D process, the planning is one of the most important sectors because it drives the direction of R&D. In this study, we suggest the assessment criteria to select a strategic energy technology R&D programs by the analytic hierarchy process, which is one of multi-criteria decision making method (MCDM)We structure 2 tiers of hierarchy for assessing a big-sized R&D program and also establish 6 criteria in the level 1, which are energy environment, economic spin-off, technical spin-off, marketability, KIER mission, and cost. We allocate the relative weights of criteria by checking the values of consistency ratio as making pairwise comparisons. The result of this research will provide the decision makers as they select a right well focused R&D program.

• 신재생에너지
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• 제19권4호
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• pp.53-60
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• 2023

The Computational Fluid Dynamics (CFD) model is a method of studying the flow phenomenon of fluid using a computer and finding partial differential equations that dominate processes such as heat dispersion through numerical analysis. Through CFD, a lot of information about flow disorders such as speed, pressure, density, and concentration can be obtained, and it is used in various fields from energy and aircraft design to weather prediction and environmental modeling. The simulation used for fluid analysis in this study utilized Gexcon's (FLACS) CODE, such as Norway, through overseas journals, for the accuracy of the analysis results through many experiments. It was analyzed that a technology for treating two or more catalysts with physical properties under low-temperature atmospheric pressure conditions could not be found in the prior art. Therefore, it would be desirable to establish a continuous plan by reinforcing data that can prove the effectiveness of producing efficient synthetic oil (renewable oil) through the application that pyrolysis under low-temperature and atmospheric pressure conditions.

• Nuclear Engineering and Technology
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• 제54권7호
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• pp.2728-2735
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• 2022

The research on the flow and heat transfer characteristics of lead bismuth(LBE) is significant for the thermal-hydraulic calculation, safety analysis and practical application of lead-based fast reactors(LFR). In this paper, a new CFD model is proposed to solve the thermal-hydraulic analysis of LBE. The model includes two parts: turbulent model and turbulent Prandtl, which are the important factors for LBE. In order to find the best model, the experiment data and design of 19-pin hexagonal rod bundle with spacer grid, undertaken at the Karlsruhe Liquid Metal Laboratory (KALLA) are used for CFD calculation. Furthermore, the turbulent model includes SST k - 𝜔 and k - 𝜀; the turbulent Prandtl includes Cheng-Tak and constant (Pr_t =1.5,2.0,2.5,3.0). Among them, the combination between SST k - 𝜔 and Cheng-Tak is more suitable for the experiment. But in the low Pe region, the deviation between the experiment data and CFD result is too much. The reason may be the inlet-effect and when Pe is in a low level, the number of molecular thermal diffusion occupies an absolute advantage, and the buoyancy will enhance. In order to test and verify versatility of the model, the NCCL performed by the Nuclear Thermal-hydraulic Laboratory (Nuthel) of Xi'an Jiao tong University is used for CFD to calculate. This paper provides two verification examples for the new universal model.

• Journal of information and communication convergence engineering
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• 제19권2호
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• pp.67-72
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• 2021

Wireless sensor networks (WSNs) require an enormous number of sensor nodes (SNs) to maintain processing, sensing, and communication capabilities for monitoring targeted sensing regions. SNs are generally operated by batteries and have a significantly restricted energy consumption; therefore, it is necessary to discover optimization techniques to enhance network lifetime by saving energy. The principal focus is on reducing the energy consumption of packet sharing (transmission and receiving) and improving the network lifespan. To achieve this objective, this paper presents a novel improved energy-efficient cluster-based routing protocol (IECRP) that aims to accomplish this by decreasing the energy consumption in data forwarding and receiving using a clustering technique. Doing so, we successfully increase node energy and network lifetime. In order to confirm the improvement of our algorithm, a simulation is done using matlab, in which analysis and simulation results show that the performance of the proposed algorithm is better than that of two well-known recent benchmarks.