• Journal of the Korea institute for structural maintenance and inspection
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• v.21 no.3
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• pp.54-59
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• 2017

GGBFS (Ground Granulated Blast Furnace Slag) is a byproduct with engineering advantages and HVSC (High Volume Slag Concrete) is widely attempted due to active utilization and reduction of eco-load. In the present work, characteristics of drying shrinkage and early-aged behavior are evaluated for the concrete with 65% replacement ratio of GGBFS and 50MPa of design strength. For the work, 3 different mix conditions are considered and several tests including slump flow, compressive strength, drying and autogeneous shrinkage are performed. From the test, OPC 100 mixture without replacement shows higher strength development before 7 days, however the strength reduction in concrete replaced with GGBFS is not significant due to sufficient free water for cement hydration. OPC 100 mixture also shows significant drying shrinkage due to a great autogeneous shrinkage before 3 days. In the concrete with GGBFS replacement, the drying shrinkage behavior is improved due to relatively small deformation by autogeneous shrinkage. The mixture (OPT BS 65) with lower w/b ratio (0.27) and unit content of water ($160kg/m^3$) shows more improved shrinkage behavior than BS 65 mixture which has simple replacement of GGBFS with 0.30 of w/b and $165kg/m^3$ of water unit content.

• Korean Journal of Organic Agriculture
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• v.26 no.1
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• pp.141-149
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• 2018

This experiment was conducted to investigate the effects of multi-enzyme on growth performance, intestinal morphology, and nutrient digestibility of weaned pigs. A total 36 weaned pigs ($5.92{\pm}0.48kg\;BW$; 28 d old) were randomly allotted to 2 dietary treatments (3 pigs/pen, 6 replicates/treatment) in a randomized complete block design. The dietary treatments were a typical diet based on corn and soybean meal (CON) and CON with 0.1% multi-enzyme (Multi; mixture of ${\beta}-mannanase$, xylanase, ${\alpha}-amylase$, protease, ${\beta}-glucanase$, and pectinase). Pigs were fed their respective diets for 6 wk. Measurements were growth performance, morphology of ileum, apparent ileal digestibility and apparent total tract digestibility of dry matter, crude protein, and energy of weaned pigs. There were no significant differences on growth performance during overall experimental period. No differences were found for the morphology of ileum and nutrient digestibility between CON and Multi groups. Therefore, the results in the current study indicated that multi-enzyme supplementation in diets had no effects on growth performance, intestinal morphology, and nutrient digestibility of weaned pigs.

• Korean Journal of Organic Agriculture
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• v.26 no.1
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• pp.151-161
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• 2018

This study was designed to investigate the effects of multi-enzyme on diarrhea and immune responses of weaned pigs. A total 36 weaned pigs ($5.92{\pm}0.48kg\;BW$; 28 d old) were randomly allotted to 2 dietary treatments (3 pigs/pen, 6 replicates/treatment) in a randomized complete block design. The dietary treatments were a typical diet based on corn and soybean meal (CON) and CON with 0.1% multienzyme (Multi; mixture of ${\beta}-mannanase$, xylanase, ${\alpha}-amylase$, protease, ${\beta}-glucanase$, and pectinase). Pigs were fed their respective diets for 6 wk. Frequency of diarrhea, levels of packed cell volume (PCV), white blood cells (WBC), immunoglobulins, cortisol, tumor necrosis $factor-{\alpha}$ ($TNF-{\alpha}$), transforming growth $factor-{\beta}$ ($TGF-{\beta}$), and C-reactive protein (CRP) were measured. Multi group tended to decrease (p<0.1) diarrhea frequency than CON group during 2 wk after weaning. Lower values of PCV on d 3 (p<0.05) and d 7 (p<0.1) were found in Multi group compared with CON group. There were no significant differences on WBC number and immunoglobulin (Ig) M and A between Multi and CON groups. However, Multi group tended to increase (p<0.1) Ig G on d 7 than CON group. Moreover, Multi group showed modulated immune responses, indicated by decreased levels of cortisol (p<0.05) on d 7 and 14, $TNF-{\alpha}$ on d 3 (p<0.05) and d 7 (p<0.10), $TGF-{\beta}$ on d 2 (p<0.05) and d 7 (p<0.10), and CRP (p<0.10) on d 3 and 7 after weaning compared with CON group. Consequently, inclusion of multi-enzyme in diets for weaned pigs improved gut health and modulated immune responses of weaned pigs.

• Journal of the Korean GEO-environmental Society
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• v.17 no.5
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• pp.27-36
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• 2016

Low Impact Development (LID) techniques are eco-friendly storm water management process for water circulation restoration and non-point pollutant reduction. In this study, four LID techniques (Small constructed wetland, Infiltration trench box, Infiltration trench, Vegetated swale) were selected and installed as a real size at the real site. All facilities were evaluated as monitoring under the real environmental climate situation and an artificial rain with exceeding design rainfall. In various rainfall, runoff reduction efficiency and non-point pollutant removal efficiency are increased to the bigger Surface Area of LID (SA)/Catchment Area (CA) ratio and the bigger Storage Volume of LID (SV)/Catchment Area (CA) ratio. Runoff did not occur at all rainfall event (max. 17.2 mm) in infiltration trench and vegetated swale. But Small constructed wetland was more efficient at less than 10 mm, a efficiency of infiltration trench box was similar at different rainfall. Although different conditions (such as structural material of LID, rainfall flow rate, antecedent dry periods), LID techniques are good effects not only water circulation improvement but also water quality improvement.

• Journal of Environmental Science International
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• v.30 no.9
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• pp.709-717
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• 2021

This study evaluated the growth, physiological responses and productivity based on the intercropping ratio of cherry tomato (Lycopersicon esculentum L.) with basil (Ocimum basilicum L.). on the rooftops to determine out the efficient ratio in urban agriculture. From April to September 2019, an experiment was conducted on the rooftop of Konkuk University Glocal Campus. Cherry tomato and basil were selected as companion plants for eco-friendly urban agriculture on the rooftops. Each plot was created with a width of 100 cm, length of 100 cm, and height of 25 cm. After installing drainage and waterproof layers from bottom to top, substrate was laid out with a height of 20 cm. Intercropping ratio was consisted of a single tomato plant (TC), 2:1 tomato to basil (T₂B₁), 1:1 tomato to basil (T₁B₁), 1:2 tomato to basil 2 (T₁B₂), and a single basil plant (BC), were conducted using a randomized complete plot design with five treatments and three replication (a total 15 plots). Measurements were divided into growth, physiological responses, and productivity parameters, and detailed items were investigated and analyzed by classifying them into plant height, leaf length, leaf width, number of leaves, root length, root collar caliper, chlorophyll contents, fresh weight, dry weight, number of fruit, fruit caliper, fruit weight, and sugar content. Comparative analyses of cherry tomato with basil plants by intercropping ratio, growth, physiological, and productivity responses are determined to be efficient when the ratio of cherry tomato to basil ratio is 2:1 or 1:1.

• Korean Journal of Heritage: History & Science
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• v.45 no.1
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• pp.174-189
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• 2012

This study aims to examine the traditional living space to reflect the environment-friendly design methods and principles of reestablishment. To do so, this study carried on a related literature study and field survey. The traditional living space in terms of the environmental friendliness is reflected on site selection and space composition, and utilization of natural energy and natural materials. Focused on the Kwangajeong in Yangdong Village, this study is to identify eco-friendly techniques on the traditional living space. As a result, it shows that Kwangajeong with the side of the southeast in site selection had been considered in aspect of environmental control such as sunshine and solar radiation. Also building construction techniques had been used to minimize the variation of terrain. In aspect of environmental conservation, Kwangajeong had structurally arranged the gate, an inner yard and an inner floor to allow good ventilation. In aspect of space composition, Kwangajeong with the emphasis of scenic view had utilized the methods that attract external landscape through the control of its fences. Environment-friendly techniques and control principles in traditional space had been developed by a long experience through the long periods and the traditional techniques suitable for local climate and local environment have been developed. The technical development of these techniques to resolve the global environmental and energy issues and create a more pleasant living environment of human beings might be critical.

• Korean Journal of Heritage: History & Science
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• v.44 no.3
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• pp.164-177
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• 2011

This study aims to examine the traditional living space to reflect the environment-friendly design methods and principles of reestablishment. To do so, this study carried on a related literature study and field survey. The traditional living space in terms of the environmental friendliness is reflected on site selection and space composition, and utilization of natural energy and natural materials. Focused on the Kwangajeong in Yangdong Village, this study is to identify eco-friendly techniques on the traditional living space. As a result, it shows that Kwangajeong with the side of the southeast in site selection had been considered in aspect of environmental control such as sunshine and solar radiation. Also building construction techniques had been used to minimize the variation of terrain. In aspect of environmental conservation, Kwangajeong had structurally arranged the gate, an inner yard and an inner floor to allow good ventilation. In aspect of space composition, Kwangajeong with the emphasis of scenic view had utilized the methods that attract external landscape through the control of its fences. Environment-friendly techniques and control principles in traditional space had been developed by a long experience through the long periods and the traditional techniques suitable for local climate and local environment have been developed. The technical development of these techniques to resolve the global environmental and energy issues and create a more pleasant living environment of human beings might be critical.

• Journal of Navigation and Port Research
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• v.43 no.3
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• pp.143-152
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• 2019

In this paper, the towing stability of the LNG bunker barge was estimated. Currently, LNG bunkering barge is being developed for the bunkering of LNG (Liquefied Natural Gas), an eco-friendly energy source. Since the LNG bunkering barge assumes the form of a towed ship connected to the tow line, the towing stability of the LNG bunker barge is crucial f not only for the safety of the LNG bunker barge but also the neighboring sailing vessels. In the initial stages, a numerical code for towing simulation was developed to estimate the towing stability of the LNG bunkering barge. The MMG (Maneuvering Mathematical modeling Group) model was applied to the equations of motion while the empirical formula was applied to the maneuvering coefficients for use in the initial design stage. To validate the developed numerical code, it was compared with published calculation and model test results. Towing simulations were done based on the changing skeg area and the towing position of the LNG bunkering barge using the developed numerical codes. As a result, the suitability of the designed stern skeg area was confirmed.

• Journal of the Korea Convergence Society
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• v.10 no.9
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• pp.69-74
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• 2019

The purpose of this study is to compare the efficiency of bacteria removal of three different types of hand washing methods. This study performed a convenient sampling of 30 volunteers in cross-over design. The study divided the 30 volunteers into three random groups. The three groups were asked to use antiseptic soap, alcohol-based hand disinfectant, and disposable wet wipes respectively. The result of the study showed that mean log reduction values after each had washing method were $-0.45({\pm}0.69)$ with antiseptic soap and water, $-1.19({\pm}0.52)$ with alcohol-based hand disinfectant and $-0.75({\pm}0.58)$ with disposable wet wipes. The difference was statistically significant when using alcohol-based hand disinfectant compared to the other two methods (p=0.000). According to this study, alcohol-based hand disinfectant was the most effective product based on bacteria removal for hand washing. Advantages of using alcohol-based hand disinfectant are that it is cost-effective and easy to buy, also eco-friendly. Therefore, to prevent infectious disease, providing alcohol-based hand disinfectant to every corner of the community will be very helpful.

• Korean Journal of Construction Engineering and Management
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• v.20 no.5
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• pp.21-30
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• 2019

Environmental and energy issues such as abnormal climate and depletion of fossil fuel due to global warming have emerged as a critical task to threaten human survival. As a result, interest in the Zero Energy Building is increasing as it is an innovative building that can significantly contribute to building energy reduction and greenhouse gas reduction. In the market, however, the added cost of construction is a major stumbling block to the revitalization of the Zero Energy certification. In this study, general private apartment complexes were selected for research, detailed elements for Zero Energy certification were presented based on the construction criteria for eco-friendly houses from the initial design stage, and the cost efficiency analysis of the components for certification were presented. It has been analyzed that only Grade 3 certification can be implemented in apartments due to technical level and physical limitations. Also, after reviewing the cost trend during the lifecycle cost, all expenses can be recovered within 13 years after completion only in the case of grade 5 of the Zero Energy Building. The additional costs proposed in the present study are reflected appropriately in the review of projects for apartments scheduled for order in the future to contribute to the revitalization of the Zero Energy Building certification.