• 한국지하수토양환경학회지:지하수토양환경
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• 제19권3호
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• pp.94-103
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• 2014

In this study washing efficiency and desorption isotherms for heavy petroleum oil (HPO), Zn, and Pb bound to complex contaminated soils were examined using various soil flushing agents. Sodium dodecyl sulfate (SDS), methanol, ethylene diamine tetraacetic acid (EDTA), and citric acid were selected as soil flushing agents. 3% (w/v) and 4% SDS showed the highest removal efficiency for HPO, but the difference was not statistically significant (p > 0.05). Thus, 3% SDS was chosen as the best soil flushing agent for HPO. In the case of heavy metals, 0.1-M EDTA showed the highest removal efficiencies. But 0.05-M citric acid was selected due to its economic and eco-friendly strengths. The desorption isotherms obtained using Freundlich and Langmuir models indicated that the maximum desorption characteristics ($K_F$ and $Q_{max}$) of HPO with 4% SDS and 90% methanol and heavy metals with 0.1-M EDTA and 0.1-M citric acid, respectively, were markedly lower than in other cases. In addition, when 4% SDS and 90% methanol were used for HPO in the range of $C_e$ higher than 600 mg/L, and when 0.1M citric acid and 0.1M EDTA were used for Zn and Pb in the range of $C_e$ higher than 300 and 100 mg/L, respectively, the distribution constant converged to certain levels. Thus, constant values of $K_U$ and $K_L$ were determined. It was found that these constants represent the maximum desorption capacity and they can be used as distribution coefficients of desorption equilibrium for the flushing agents. The results of this study provided fundamental information for the selection of the best agents as well as for the process design and operation of soil washing/soil flushing of complex contaminated soils.

• 한국유기농업학회지
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• 제22권4호
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• pp.695-703
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• 2014

본 연구는 온실 내 오이재배에서 크게 문제가 되는 흰가루병의 친환경적 방제를 위한 방법으로 올레산의 사용에 대한 효과와 올레산 처리 시 적정 농도를 구명하기 위해 수행되었다. 실험은 상명대학교 플라스틱 실험온실에서 '백봉다다기(농우바이오, 한국)'를 사용하여 수행하였다. 오이의 흰가루병에 대한 올레산의 처리효과와 적정농도 구명을 위한 실험은 무처리구를 대조구로 하고 올레산 2000 ppm, 4000 ppm, 6000 ppm, 8000 ppm을 각각 처리하고 병피해도, 병반면적율, 방제가, 약해피해도 및 약해면적율을 조사하였다. 방제가는 처리 3일 후에 조사했으며, 재발생 조사는 55일간 수행하였다. 시설 내 주야간 온도는 $23/15^{\circ}C$로 조절하였고, 상대습도는 조절하지 않았다. 오이의 흰가루병 방제에 올레산은 매우 효과적인 것으로 나타나서 화학적 방제를 대체할 수 있는 좋은 친환경 유기농자재로 판단되었다. 올레산은 2000 ppm 농도로 분무하는 것이 방제가가 높으며, 약해가 발생하지 않는 것으로 조사되었다. 또한 흰가루병의 예방 및 재발생 방지를 위해 3주에 1회씩 올레산을 분무하는 것이 좋을 것으로 사료된다.

• 한국해양공학회지
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• 제35권5호
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• pp.327-335
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• 2021

Microcracks can rapidly grow and develop in high-strength steels used in offshore structures. It is important to render these microcracks harmless to ensure the safety and reliability of offshore structures. Here, the dependence of the aspect ratio (As) of the maximum depth of harmless crack (a_hlm) was evaluated under three different conditions considering the threshold stress intensity factor (Δk_th) and residual stress of offshore structural steel F690. The threshold stress intensity factor and fatigue limit of fatigue crack propagation, dependent on crack dimensions, were evaluated using Ando's equation, which considers the plastic behavior of fatigue and the stress ratio. a_hlm by peening was analyzed using the relationship between Δk_th obtained by Ando's equation and Δk_th obtained by the sum of applied stress and residual stress. The plate specimen had a width 2W = 12 mm and thickness t = 20 mm, and four value of As were considered: 1.0, 0.6, 0.3, and 0.1. The a_hlm was larger as the compressive residual stress distribution increased. Additionally, an increase in the values of As and Δk_th(l) led to a larger a_hlm. With a safety factor (N) of 2.0, the long-term safety and reliability of structures constructed using F690 can be secured with needle peening. It is necessary to apply a more sensitive non-destructive inspection technique as a non-destructive inspection method for crack detection could not be used to observe fatigue cracks that reduced the fatigue limit of smooth specimens by 50% in the three types of residual stresses considered. The usefulness of non-destructive inspection and non-damaging techniques was reviewed based on the relationship between a_hlm, a_NDI (minimum crack depth detectable in non-destructive inspection), a_{cr N} (crack depth that reduces the fatigue limit to 1/N), and As.

• 한국의류산업학회지
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• 제21권1호
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• pp.112-119
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• 2019

This study had a purpose of further investigating and developing the usage of the eco-friendly functional dye that has physiological and pharmacological functions. This study was implemented complex dyeing method which used both natural dyes such as Gardenia jasminoides J.Ellis colorant, which are the yellow dyes that have high brightness and low chroma, and Xanthium strumarium L. extract. The silk fabrics were used to dye in various methods. They were also used to investigate functionalities dyed fabrics by various treating method, such as their color fastness, antibacterial activities and deodorization, the following were obtained. The fabrics that were dyed with herbs had decreasing brightness as the herbs extract concentrations were increased and had subtly changing chroma. But, because their K/S values were under 0.5, they were not properly dyed. Color fastness differed according to the natural dyes and herbs' complex dyeing order. The Color fastness was good when the fabrics were dyed with the colorant first, and then with the herb. When the fabrics were dyed with mixture dyeing solution, the natural dye and the herb extract, the herb didn't affect the dyeabilities of fabrics as much. When the fabrics were dyed with the mixture of the colorant and the herb extract, the dyeabilities didn't have much changes. However, their color fastnesses were improved a little bit due to the complex dyeing condition. When the fabrics were dyed with the mixture of the colorant and the herbs extract, their antibacterial activities and deodorization were increased.

• Animal Bioscience
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• 제34권3_spc호
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• pp.363-370
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• 2021

Objective: The effect of garlic powder (GP) and phenyl acetic (PA) acid throughout the fattening period of broiler chickens on performance, blood parameters, immune, and antioxidant parameters as well as carcass traits was evaluated. Methods: A total of 210 day-old Cobb broiler chicks were randomly distributed into seven dietary treatments having five replications with six chicks per replicate. The first group (control) fed a basal diet without supplements, whereas the 2nd, 3rd, and 4th group were fed basal diet plus 0.25, 0.50, and 0.75 g GP/kg diet, respectively and the group 5th, 6th, and 7th were fed on the basal diet plus 0.25, 0.50, and 0.75 g PA/kg diet. Results: Broiler body weight and gain at 21 and 42 days were increased (p<0.05) with diets supplemented with GP and PA. Red blood cells and hemoglobin were improved in chickens fed diets enriched with GP. Broiler chickens received diets containing either GP or PA recorded the higher values (p<0.05) of total protein, globulin, high-density lipoprotein, immunoglobulin M (IgM), and IgG, superoxide dismutase and total antioxidant capacity; while, blood total cholesterol, low-density lipoprotein, aspartate-aminotransferase, and malondialdehyde were lowered (p<0.05) compared to control-diet. Liver and immune-related organs weight were improved (p<0.05) in broilers fed diet supplemented with GP and PA. Conclusion: Feeding of GP or PA in diet had positive effects on performance traits and immunological, antioxidant and physiological status of broilers. Thus, the use of tested feed additives as an eco-friendly alternative to antibiotics produced a positive effect on animal health.

• 한국유기농업학회지
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• 제29권1호
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• pp.125-136
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• 2021

본 연구에서는 meta-analysis를 통해 TJP의 발현량과 육계의 생산성 간의 상관관계를 살펴보았다. TJP의 발현량은 생산성의 향상과 밀접한 관계가 있는 것으로 나타났으며, 특히 occludin의 발현이 육계의 생산성과 가장 큰 상관관계를 보이는 것으로 나타났다. Occludin 발현량 조절과 장 점막 건강이 육계 생산성 향상을 위한 영양 관리 전략 지표로 활용될 수 있을 것이다.

• Current Photovoltaic Research
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• 제10권2호
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• pp.56-61
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• 2022

Recently, the expansion of the domestic solar market due to the promotion of eco-friendly and alternative energy-related policies is promising, and it is expected to lead the high-efficiency/high-power module market based on M10 or larger cells to reduce LCOE, 540-560W, M12 based on M10 cells Compared to the existing technology with an output of 650-700W based on cells, it is necessary to secure competitiveness through the development of modules with 600W based on M10 cells and 750W based on M12 cells. For the development of high efficiency/high-power n-type bifacial, it is necessary to secure a lightweight technology and structure due to the increase in weight of the glass to glass module according to the large area of the module. Since the mechanical strength characteristics according to the large area and high weight of the module are very important, design values such as a frame of a new structure that can withstand the mechanical load of the Mechanical Load Test and the location of the mounting hole are required. In this study, a structural analysis design model was introduced to secure mechanical reliability according to the enlargement of the module area, and the design model was verified through the mechanical load test of the actual product. It can be used as a design model to secure the mechanical reliability required for PV modules by variables such as module area, frame shape, and the location and quantity of mounting holes of the structural analysis model verified. A relationship of output drop can be obtained.

• 한국의류학회지
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• 제45권6호
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• pp.1052-1062
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• 2021

This study aims to confirm the possibility of Ultra-Violet (UV)-printed 3D printing materials using thermal polyurethane (TPU) with CMYK colors by applying an eco-friendly UV digital printing process. A UV-printed 3D printing TPU material was prepared with cycles of UV printing and CMYK colors. Dyeability of the 3D TPU samples with cycles of UV printing and CMYK were analyzed for thickness, weight, surface roughness, reflectance, colorimetry, and K/S values. The thickness and weight of 3D-printed TPU samples with cycles of UV printing are increased with overprints from 1 to 5. The surface roughness of 3D-printed TPU samples with increasing UV prints were decreased, meaning that the surface of TPU samples becomes gradually smoother. The reflectance spectra of CMYK UV-printed TPU samples showed the surface reflectance within each characteristic wavelength of CMYK. The 3D-printed TPU samples, subjected to UV printing twice or more, showed low surface reflectance. After examining the L^*a^*b^* of the 3D-printed TPU samples by the cycles of UV printing, the study found that the more UV got printed more than 2 times, the closer the color to each CMYK.

• 농업과학연구
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• 제49권4호
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• pp.771-783
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• 2022

In this study, the feasibility of alternative tractor Roll Over Protective Structure (ROPS) designed to evaluate conditions required for testing was confirmed. In accordance with Organization for Economic Cooperation and Development (OECD) code 4, the required load energy of the tractor ROPS was determined. First, the tractor ROPS test was performed and a repeated test was performed using a simplified ROPS as an alternative tractor ROPS. The test procedure is first rearward, second lateral, and last forward based on ROPS. The load test device consists of a load cell that measures force and a LVDT that measures deformation. Precision was confirmed by calculating the relative standard deviation of the simplified ROPS repeated test. Accuracy was analyzed by calculating the mean relative error between the mean measured values in the simplified ROPS test and the tractor ROPS test. As a result, the relative standard deviation was less than 2.5% for force and 3.3% for maximum deformation overall, showed the highest precision in lateral load. The mean relative error value for force measured at the lateral load of simplified ROPS was 0.5%, showing the highest accuracy. In the front load test, the mean relative error of maximum deformation was 20.5%, showing the lowest accuracy. The mean relative error (MRE) was high in the forward load test was because of structural factors of the ROPS. The simplified ROPS model is expected to save money and time spent preparing tractors.

• 한국환경농학회지
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• 제42권4호
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• pp.457-464
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• 2023

The rendering residue generated by rendering disposal, an eco-friendly livestock carcass disposal method, is a useful agricultural resource. Methods for recycling this are being actively researched, and this study investigated the impact of applying rendered residue directly to soil on crop productivity and the agricultural environment. The chemical properties of the rendering residue were examined. The pH, OM, T-N, T-P, CaO, K₂O, and MgO content values were 5.47%, 59.8%, 9.22%, 2.96%, 2.16%, 0.51% and 0.10%, respectively. Treatment conditions were divided into control, inorganic fertilizer, and rendering residue, and rendering residue corresponding to 50, 100, and 200% nitrogen content was applied based on the amount of inorganic fertilizer nitrogen input. Greenhouse gases and ammonia were collected during the cultivation period. Rendering residue increased both the yield and growth of peppers and was effective in improving nutrients such as pH and OM of the soil after harvest. However, compared to inorganic fertilizer treatment, it increased emissions of nitrous oxide and methane as well as ammonia. It is judged that the direct agricultural use of rendering residue is difficult, and a utilization method is needed.