• Journal of the Korean Institute of Landscape Architecture
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• v.26 no.3
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• pp.118-133
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• 1998

The residents, living in multi-family housing, prefer to have healthy and natural outdoor environmental for better human and environment quality. Thus, providing the high qulity of amenity has become a popular word in site planning and housing developments field. However, the scope and definition of amenity have not yet clearly identified and it becomes and issue in planning and development field. The purpose of this study isto examine and to evaluate the amenity and its implicationi for site planning so that analysis methods such as to interview and survey with residents were carried out. The results of this study are summarized below; The amenity of residential environment means total environmental quality to the residents in a broad sense. Abundent green environment would be very important factor to increase the amenity of residential environment so that the expansion of green field would improve the quality of multifamily housing. The expansion of green environment and biotope was the most important factor to increase the symbiosis system between residents and outdoor environment. And the amenity should be conformed to the certain standand of environmental quality and the high quality of amenity would be increased significantly in the future for residental developments. Thus, it should be accomplished by preparing practical methods in means of discriminative strategy products planning principle.

• Food Science and Biotechnology
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• v.15 no.3
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• pp.478-481
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• 2006

This study investigated the antimicrobial activity of soy protein isolate (SPI) film containing green tea extract (GTE, 1-4%, w/w) on dental caries-inducing bacterium (Streptococcus mutans), food pathogenic (Staphylococcus aureus, Escherichia coli 0157, Salmonella typhimurium), and spoilage (Pseudomonas aeruginosa) bacteria. The physical and mechanical properties of the SPI film containing GTE were also studied. The SPI film containing GTE (4%, w/w) exhibited good antimicrobial activity against S. mutans and S. aureus. The antimicrobial activity of the SPI film containing GTE increased against S. mutans as the concentration of GTE increased up to 4%(w/w). SPI films containing GTE showed lower tensile strength and elongation, and higher total soluble matter than those of control SPI film. Therefore, GTE can be used as one of antimicrobial agents for anti-dental caries and food packaging films.

• Korean Journal of Metals and Materials
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• v.50 no.7
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• pp.531-538
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• 2012

In this study, we evaluated the fluidity of the Al-Zn based alloys which exhibit excellent mechanical properties. We conducted computer simulations of fluid flow using the results of DSC, DTA analysis and Java-based Materials Properties software (J. Mat. Pro). Such computer simulations were then compared with the results obtained from experimental observations. The computer simulation results and the experimental results were very similar in fluidity length. It was found that the fluidity length of Al-Zn alloys is improved by increasing the Zn content while decreasing the solidus temperature of an alloy. In addition, we elucidate the effect of Zn addition on variations in different mechanical properties and the microstructure characteristics of (Al-xZn3Cu0.4Si0.3Fe) x=20, 30, 40, and 45 wt% alloys fabricated by gravity casting.

• Korean Journal of Metals and Materials
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• v.48 no.10
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• pp.936-941
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• 2010

Al-Zn based alloys are the most common types of wrought Al alloys. Although Al-Zn alloys have high strength, they cannot be applied to a conventional casting process. In this study, Al-Zn-based alloys applicable to a die casting process were developed successfully. The developed Al-45 wt% Zn-based alloys showed a fine equiaxed grain structure and high strength. A fine equiaxed grain having an average size of $25{\mu}m$ was obtained by the die casting process. The UTS and elongation of the new alloy are 475 MPa and ~3.5%, respectively. In addition, we elucidate the effect of a Zn addition on variations in different mechanical properties and the microstructure characteristics of (Al96.3-xZnxCu3Si0.4Fe0.3) x=20, 30, 40, and 45 wt% alloys fabricated by a die casting process.

• Nuclear Engineering and Technology
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• v.46 no.1
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• pp.101-108
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• 2014

About 40% of reactors in the world are being operated beyond design life or are approaching the end of their life cycle. During long-term operation, various degradation mechanisms occur. Fatigue caused by alternating operational stresses in terms of temperature or pressure change is an important damage mechanism in continued operation of nuclear power plants. To monitor the fatigue damage of components, Fatigue Monitoring System (FMS) has been installed. Most FMSs have used Green's Function Approach (GFA) to calculate the thermal stresses rapidly. However, if temperature-dependent material properties are used in a detailed FEM, there is a maximum peak stress discrepancy between a conventional GFA and a detailed FEM because constant material properties are used in a conventional method. Therefore, if a conventional method is used in the fatigue evaluation, thermal stresses for various operating cycles may be calculated incorrectly and it may lead to an unreliable estimation. So, in this paper, the modified GFA which can consider temperature-dependent material properties is proposed by using an artificial neural network and weight factor. To verify the proposed method, thermal stresses by the new method are compared with those by FEM. Finally, pros and cons of the new method as well as technical findings from the assessment are discussed.

• Current Photovoltaic Research
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• v.9 no.3
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• pp.106-109
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• 2021

In order to perform photovoltaic (PV) operation and management (O&M) efficiently, individual PV module monitoring is becoming more important. In this research, we developed wireless IoT sensor which can monitor individual photovoltaic modules. This IoT sensor can detect the output voltage, current and module temperature of individual modules and provide monitored data by wireless communication. Measured voltage error was 1.23%, and it shows 16.6 dBM, 0.42sec and 7.1 mA for voltage, transmittance output, response time and mean power consumption, respectively. IoT sensors were demonstrated in the test field with real climate environment condition and each of 5 sensors showed precise results of voltage, current and temperature. Also, sensors were compared with commercial power-optimizers and showed result difference within 5%.

• Journal of Climate Change Research
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• v.9 no.4
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• pp.435-443
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• 2018

Climate technology applied to address climate change requires a comprehensive review such as environmental and social acceptability in addition to economic feasibility. Not only mitigation and adaptation technologies, but also integration of climate technologies into a business model with other relevant technologies including ICT, finance, and policy instruments could enhance technical, economic, and environmental performances to respond to climate changes. However, many climate projects (and business models) are currently not designed to consider adequately complex climate?related issues. In addition, there is a lack of research on assessment systems that can comprehensively evaluate business feasibility of such models. In this study, we developed a system consisting of nine major indicators in four fields to assess climate technology-based business models. Each indicator was weighed using the analytic hierarchy process (AHP) for systematic assessment of business models. The process can be utilized as a tool to guide improvement of climate technology business models.

• Journal of electromagnetic engineering and science
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• v.19 no.1
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• pp.6-12
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• 2019

An IE-FFT algorithm is implemented and applied to the electromagnetic (EM) solution of perfect electric conducting (PEC) scattering problems. The solution of the method of moments (MoM), based on the magnetic field integral equation (MFIE), is obtained for PEC objects with closed surfaces. The IE-FFT algorithm uses a uniform Cartesian grid to apply a global fast Fourier transform (FFT), which leads to significantly reduce memory requirement and speed up CPU with an iterative solver. The IE-FFT algorithm utilizes two discretizations, one for the unknown induced surface current on the planar triangular patches of 3D arbitrary geometries and the other on a uniform Cartesian grid for interpolating the free-space Green's function. The uniform interpolation of the Green's functions allows for a global FFT for far-field interaction terms, and the near-field interaction terms should be adequately corrected. A 3D block-Toeplitz structure for the Lagrangian interpolation of the Green's function is proposed. The MFIE formulation with the IE-FFT algorithm, without the help of a preconditioner, is converged in certain iterations with a generalized minimal residual (GMRES) method. The complexity of the IE-FFT is found to be approximately $O(N^{1.5})$and $O(N^{1.5}logN)$ for memory requirements and CPU time, respectively.

• Journal of the Korean Solar Energy Society
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• v.38 no.6
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• pp.15-26
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• 2018

It is difficult to check the exact building energy consumption reduction such as when green remodeling of buildings, because it is due to outdoor air temperature over the years. And in Korea although Big Data of building energy consumption is collected and managed through "The Information System of the Building Energy and Greenhouse Gases" it is underutilized because of non calibration of outdoor air temperature change. Therefore, this study aims to develope calibration method of building energy consumption by outdoor air temperature according to micro climates, and building use types. As a result of analysis, Regression equations of Building energy consumption and $HDD_m/CDD_m$ are derived and calibration method is developed by Regression coefficient.

• Architectural research
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• v.20 no.4
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• pp.121-128
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• 2018

Given the barriers to implement green building rating systems, Building Information Modeling (BIM) was suggested as an effective solution integrating information into one model and saving substantial time to facilitate certification process. Synergies between BIM and Leadership in Energy and Environment Design (LEED), the most widely used rating system, have been researched for a few decades. This paper demonstrates literature review about the development of integration between BIM and LEED. The research focuses on synergies between BIM and Green Standard for Energy & Environmental Design (G-SEED) in Korea, as one of important strategies to mitigate greenhouse gas emission. The research compares LEED and G-SEED related items based on evaluation contents. The result manifests G-SEED and LEED share many common items in different degrees. Therefore, it is entirely possible for G-SEED and BIM to adapt same developing mode of LEED and BIM. Moreover, the study measures the potential of BIM in application process of G-SEED certification by investigation of credits in LEED and G-SEED can be earned by BIM. The results of paper indicate the documentation support LEED and G-SEED may be prepared directly, semi-directly and indirectly via sustainability analyses software in BIM.