• Journal of the Korea institute for structural maintenance and inspection
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• v.19 no.1
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• pp.23-34
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• 2015

Recently a new damper system with Kogome truss structure was developed and its mechanical properties were verified based on the laboratory test. This paper presents a Kagome truss damper external connection method for seismic strengthening of RC frame structural system. The Kagome external connection method, proposed in this study, consisted of building structure, Kagome damper and support system. The method is capable of reducing earthquake energy on the basis of the dynamic interaction between external support and building structures using Kagome damper. The pseudo-dynamic test, designed using a existing RC frame apartment for pilot application of LH corporation, was carried out in order to verify the seismic strengthening effects of the proposed method in terms of the maximum load carrying capacity and response ductility. Test results revealed that the proposed Kagome damper method installed in RC frame enhanced conspicuously the strength and displacement capacities, and the method can resist markedly under the large scaled earthquake intensity level.

• Journal of the Korea institute for structural maintenance and inspection
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• v.24 no.2
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• pp.9-14
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• 2020

Four developed patents have applied for a new type of Composite Cyclone Scrubber followed by the previous research (Cho and Kim, 2017), including dust reducing fan with filters. Regarding target installation and maintenance cost, 64% reduction for investment costs (6.2 billion won vs. 17 billion won) compared to existing road pollution reduction system, while social benefit costs increase by 43% compared to existing road pollution reduction measures (72.6 billion won vs. 50.8 billion won). The composition of the device is an air blower type spiral guide vane, and an injection pressure collecting dust efficiency. A nozzle varies Injection angle and contact range, spray liquid species (waterworks, salty water). The proposed patent tests are circulation water Time-by-Time Spray and collected 41.4% more increased micro dust since the sprayed water meets contaminated gas due to the 45° degree colliding, which is 141% increased conventional dust collector. (Ratio of collection over 85%). As regards the source of collection liquid, circulated rainwater and well water, we expect a huge amount of energy and economically saved eco-friendly system in our patent. Finally, the guided vane and metal filter reduced over 90% micro-dust, while sprayed water cleans the vane and filters, resultantly minimizing the maintenance budget. The preliminary evaluations of the developed design make it possible to reduce not only cheaper maintenance budget due to the characteristic water spraying but the cost of water comes from mainly rain and underground.

• Korean Journal of Community Nutrition
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• v.21 no.2
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• pp.190-199
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• 2016

Objectives: The purpose of this study was to identify the differences in nutrient intake according to using diuretics, symptom severity and degree of physical functioning in heart failure patients. Methods: A secondary data analysis was conducted by using baseline data of an intervention study for heart failure patients. In this study, 131 heart failure patients were included. Data were collected using medical records, NYHA (New York Heart Association functional classification) class, and 6-minute-walking test and 24-hour diet recall. Data were analyzed using descriptive statistics and Chi-square test by SPSS 21.0. Nutrient intake was assessed using CAN-pro 2.0. Results: Majority of the participants consumed total calorie less than Estimated Energy Requirement (EER) and consumed carbohydrates more than 65% of their total calorie intakes. 24.4% of the participants consumed fat more than 30% of their total calorie intakes and 23.7% consumed saturated fat more than 7% of their total calorie intakes. 100.0% of the participants consumed protein less than 7% of their total calorie intakes and 73.3% of the participants consumed more than recommended intakes of sodium. More than 90.0% of the participants consumed less than adequate intakes of potassium (90.1%) and Vitamin D (91.6%), respectively. 100% and 62.6% of the participants consumed less than Estimated Average Requirement (EAR) of magnesium and Vitamin $B_1$, respectively. Nutrient intakes in heart failure patients were different for potassium intake according to the usage of diuretics. The participants with symptom severity tended to intake protein less properly and the participants walking more than 300.0 m tended to intake sodium improperly high. Conclusions: The findings of this study indicated the need for screening nutrient intakes of heart failure patients. It is necessary to increase the intake of total calories and most nutrients and to restrict sodium intakes among heart failure patients.

• Journal of the Korea Convergence Society
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• v.2 no.2
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• pp.47-56
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• 2011

Korea Ministry of Knowledge Economy has estimated that wind power (WP) will be occupied 37% in 2020 and 42% in 2030 of the new energy sources, and also green energies such as photovoltaic (PV) and WP are expected to be interconnected with the distribution system because of Renewable Portfolio Standard (RPS) starting from 2012. However, when a large scale wind power plant (over 3[MW]) is connected to the traditional distribution system, protective devices (mainly OCR and OCGR of re-closer) will be occurred mal-function problems due to changed fault currents it be caused by Wye-grounded/Delta winding of interconnection transformer and %impedance of WP's turbine. Therefore, when Double-Fed Induction Generator (DFIG) of typical WP's Generator is connected into distribution system, this paper deals with analysis three-phase short, line to line short and a single line ground faults current by using the symmetrical components of fault analysis and PSCAD/EMTDC modeling.

• Journal of the Korean Electrochemical Society
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• v.4 no.3
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• pp.118-124
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• 2001

The Langmuir adsorption isotherm of the over-potentially deposited hydrogen (OPD H) for the cathodic $H_2$ evolution reaction (HER) at the $poly-Au|0.5M\;H_2SO_4$ aqueous electrolyte interface has been studied using cyclic voltammetric and ac impedance techniques. The behavior of the phase shift $(0^{\circ}\leq{-\phi}\leq90^{\circ})$ for the optimum intermediate frequency corresponds well to that of the fractional surface coverage $(1\geq{\theta}\geq0)$ at the interface. The phase-shift profile $({-\phi}\;vs.\;E)$ for the optimum intermediate frequency, i.e., the phase-shift method, can be used as a new method to estimate the Langmuir adsorption isotherm $(\theta\;vs.\;E)$ of the OPD H for the cathodic HER at the interface. At the poly-$Au|0.5M\;H_2SO_4$ electrolyte interface, the equilibrium constant (K) and standard free energy $({\Delta}G_{ads})$ of the OPD H are $2.3\times10^{-6}\;and\;32.2\;kJ\;mol^{-1}$, respectively.

• Journal of the Korean Electrochemical Society
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• v.11 no.1
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• pp.47-50
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• 2008

A new anode composition material comprising of SiO and Graphite has been prepared by adopting High energy ball milling (HEBM) technique. The anode material shows high initial charge and discharge capacity values of 1139 and 568 mAh/g, respectively. The electrode sustains reversible discharge capacity value of 719 mAh/g at 30th cycle with a high coulombic efficiency${\sim}99%$. Since the materials formed during initial charge process the nano silicon/$Li_4SiO_3$ and $Li_2O$ remains as interdependent, it may be expected that the composite exhibiting higher amount of irreversibility$(Li_2O)$ will deliver higher reversible capacity. In this study, constant current-constant voltage (CC-CV) charge method was employed in place of usual constant current (CC) method in order to convert efficiently all the SiO particles which resulted high initial discharge capacity at the first cycle. We improved considerably the initial discharge specific capacity of SiO/G composite by pretreatment(CC-CV).

• Journal of Microbiology and Biotechnology
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• v.20 no.11
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• pp.1563-1570
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• 2010

To construct a highly sensitive detection system for endocrine disruptors (EDs), we have compared the activity of promoters with the n-alkane-inducible cytochrome P450 gene (ALK1), isocitrate lyase gene (ICL1), ribosomal protein S7 gene (RPS7), and the translation elongation factor-1${\alpha}$ gene (TEF1) for the heterologous gene in Yarrowia lipolytica. The promoters were introduced into the upstream of the lacZ or hERa reporter genes, respectively, and the activity was evaluated by ${\beta}$-galactosidase assay for lacZ and Western blot analysis for hER${\alpha}$. The expression analysis revealed that the ALK1 and ICL1 promoters were induced by n-decane and by EtOH, respectively. The constitutive promoter of RPS7 and TEF1 showed mostly a high level of expression in the presence of glucose and glycerol, respectively. In particular, the TEF1 promoter showed the highest ${\beta}$-galactosidase activity and a significant signal by Western blotting with the anti-estrogen receptor, compared with the other promoters. Moreover, the detection system was constructed with promoters linked to the upstream of the expression vector for the hER${\alpha}$ gene transformed into the Y. lipolytica with a chromosome-integrated lacZ reporter gene under the control of estrogen response elements (EREs). It was indicated that a combination of pTEF1p-hER${\alpha}$ and CXAU1-2XERE was the most effective system for the $E_2$-dependent induction of the ${\beta}$-galactosidase activity. This system showed the highest ${\beta}$-galactosidase activity at $10^{-6}\;M\;E_2$, and the activity could be detected at even the concentration of $10^{-10}\;M\;E_2$. As a result, we have constructed a strongly sensitive detection system with Y. lipolitica to evaluate recognized/suspected ED chemicals, such as natural/synthetic hormones, pesticides, and commercial chemicals. The results demonstrate the utility, sensitivity, and reproducibility of the system for identifying and characterizing environmental estrogens.

• Journal of the Korea Organic Resources Recycling Association
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• v.25 no.2
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• pp.91-100
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• 2017

The purpose of this study is to provide a design and operation technical guideline for meeting the appropriate design criteria to bio-gasification facilities treating organic wastes. In accordance with the government's mid-to long-term policies on bio-gasification and energization of organic wastes, the expansion of the waste-to-energy (WTE) facilities is being remarkably promoted. However, because of the limitation of livestock manure containing low-concentration of volatile solids, there has been increased in combined bio-gasification without installing new anaerobic digestion facilities. The characteristics and common problems of each treatment processes were investigated for on-going 13 bio-gasification facilities. The seasonal precision monitoring of chemicophysics analysis on anaerobic digestor samples was conducted to provide guidelines for design and operation according to the progress of bio-gasification treatment. Consequently, major problems were investigated such as large deviation of organic materials depending on seasons, proper dehumidification of biogas and pretreatment of hydrogen sulfide.

• Journal of Korean Society for Atmospheric Environment
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• v.30 no.2
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• pp.188-200
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• 2014

The IPCC 5th Assessment Report (Climate Change 2013: The Physical Science Basis) was accepted at the 36th Session of the IPCC on 26 September 2013 in Stockholm, Sweden. It consists of the full scientific and technical assessment undertaken by Working Group I. This comprehensive assessment of the physical aspects of climate change puts a focus on those elements that are relevant to understand past, document current, and project future of climate change. The assessment builds on the IPCC Fourth Assessment Report and the recent Special Report on Managing the Risk of Extreme Events and Disasters to Advance Climate Change Adaptation. The assessment covers the current knowledge of various processes within, and interactions among, climate system components, which determine the sensitivity and response of the system to changes in forcing, and they quantify the link between the changes in atmospheric constituents, and hence radiative forcing, and the consequent detection and attribution of climate change. Projections of changes in all climate system components are based on model simulations forced by a new set of scenarios. The report also provides a comprehensive assessment of past and future sea level change in a dedicated chapter. The primary purpose of this Technical Summary is to provide the link between the complete assessment of the multiple lines of independent evidence presented in the main report and the highly condensed summary prepared as Policy makers Summary. The Technical Summary thus serves as a starting point for those readers who seek the full information on more specific topics covered by this assessment. Warming of the climate system is unequivocal, and since the 1950s, many of the observed changes are unprecedented over decades to millennia. The atmosphere and ocean have warmed, the amounts of snow and ice have diminished, sea level has risen, and the concentrations of greenhouse gases have increased. Total radiative forcing is positive, and has led to an uptake of energy by the climate system. The largest contribution to total radiative forcing is caused by the increase in the atmospheric concentration of $CO_2$ since 1750. Human influence on the climate system is clear. This is evident from the increasing greenhouse gas concentrations in the atmosphere, positive radiative forcing, observed warming, and understanding of the climate system. Continued emissions of greenhouse gases will cause further warming and changes in all components of the climate system. Limiting climate change will require substantial and sustained reductions of greenhouse gas emissions. The in-depth review for past, present and future of climate change is carried out on the basis of the IPCC 5th Assessment Report.

• Journal of Nutrition and Health
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• v.50 no.4
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• pp.376-382
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• 2017

Purpose: The consistent rise in the number of foreign students in Korea demands an accurate and detailed investigation into their dietary practices and nutritional status. For these international students, assimilation into new cultures can be stressful. The influence this process may have on dietary behaviors as well as overall health cannot be overlooked. Methods: The researchers in this study sought to investigate the nutritional status and dietary practices of Ghanaian students studying in Korea. A total of 81 Ghanaian male students with an average age of $29.4{\pm}4.0years$ were sampled between May and June 2016. Investigations were carried out on the general characteristics of the participants, their daily food and nutrient intakes using a 24-h dietary recall method, meal skipping practices, and the nutritional quality of their diets based on their meal skipping habits. Results: The study revealed that the daily nutrient intake of subjects did not fully meet the daily recommended nutrient intake (RNI) established by Ghanaian Ministry of Health and the World Health Organization (WHO) and Food and Agriculture Organization (FAO), particularly for energy, calcium, iron, zinc, and vitamin B2 requirements. The Nutrient Adequacy Ratio (NAR) for calcium was very low, posing a deficiency risk to the participants. Meal skipping practices among participants changed significantly after arriving in Korea. The study also compared the diet quality indicators (Nutrient Adequacy Ratio and Mean Adequacy Ratio) of those who skipped meals ${\geq}7times/week$ with those who skipped meals < 7 times/week. Participants who skipped meals ${\geq}7times/week$ were shown to have lower dietary intakes of vitamins B1 and B2 than those who skipped meals < 7 times/week. Conclusion: Ultimately, the study found that meal skipping among Ghanaian students was common, and their daily nutrient intakes did not meet the set dietary standards. Those who skipped meals ${\geq}7times/week$ had lower dietary intakes of vitamins B1 and B2 than those who skipped meals < 7 times/week. Based on our study findings, we recommend that nutrition education should be organized for the Ghanaian student community in Korea using our results as a template to draw up a nutrition program that is culturally appropriate.