• Journal of The Korean Society of Agricultural Engineers
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• v.59 no.4
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• pp.53-64
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• 2017

The equations and emission factors for estimating national GHGs are developed based on IPCC guidelines. The GHGs on livestock sector has been calculated using methodologies following 1996 IPCC guideline in South Korea although 2006 IPCC guideline was announced in 2006. The purpose of this study is to understand the implications of guideline updates for national GHGs changes in the livestock sector and analyze the effect of regional major livestock characteristics using KOSTAT time series data (1990 ~ 2014). The results show a new guideline makes GHGs reduce in the livestock sector up to 11 % with subdivided emission factors and the livestock characteristics affect regional GHGs. Gyeonggi-do, the top emitter among 16 states, records 784 thousand tons $CO_2eq.$ and Daejeon has the highest potential (82 %) of GHGs reduction. Swine is the most contributor for regional GHGs except Seoul and Gwangju, but the share of GHGs for chickens is less than 12 % in spite of the largest livestock population (87 %).

• Journal of The Korean Society of Agricultural Engineers
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• v.60 no.3
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• pp.135-148
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• 2018

Reservoir sedimentation is a major environmental issue, and various sediment load controls and plans have been proposed to secure clean and safe water resources. The objectives of this study were to estimate soil loss in the upper basins and predict sediment deposition in Ipjang reservoir using hydrologic and hydraulic model. To do so, SWAT (Soil and Water Assessment Tool) and EFDC (Environmental Fluid Dynamics Code) was used to estimate soil loss in two upper basins and to predict spatial distribution and amount of sediment deposition in the Ipjang reservoir, respectively. The hydrologic modeling results showed that annual average soil loss from the upper basins was 500 ton. The hydraulic modeling results demonstrated that sediment particles transported to the reservoir were mostly trapped in the vicinity of the reservoir inlet and then moved toward the bank over time. If long-term water quality monitoring and sediment survey are performed, this study can be used as a tool for predicting the dredging amount, dredging location and proper dredging cycle in the reservoir. The study findings are expected to be used as a basis to establish management solutions for sediment reduction.

• Journal of Bio-Environment Control
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• v.6 no.4
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• pp.242-249
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• 1997

Environmental control operations have been considerably contributed to the reduction of labor cost in both plastic film and glass greenhouses since government supported projects were begun. However, some problems are still remaining on the optimal environmental control and excessive operation due to an inflexible software regulating ventilation gear - reducers. The unadjustable software caused the damage of ventilation system, resulting in heat stresses of crops. This study was performed to develop a ventilation software controlling the vent opening level, opening sequence, based on the wind direction, and control interval according to the difference between ambient and set- up temperatures. The software included a beeper system alarming urgent cases, while a manager was remote from the greenhouse. A compatible hardware with the software was also developed by using a low-cost diffused DSP controller.

• Journal of Bio-Environment Control
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• v.16 no.3
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• pp.205-209
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• 2007

This experiment was conducted to investigate the growth of plug seedlings and yield of tomato affected by the concentration of triazole and the treatment time. The length and leaf area of tomato seed-lings were reduced by the application of triazole compared to control. Growth reduction of seedlings was greater by earlier application and higher concentration of triazole. The growth of tomato treated with hexaconazole were similar with control 4 weeks after sowing. The triazole treatment lowered the height of the first fruit set compared to control. However, triazole treatment did not affect the number of fruits and yield.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.43 no.1
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• pp.39-45
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• 2010

Chlorella has been reported to have certain beneficial physiological effects, including hypocholesterolemic, antihypertensive, antioxidative, and anti-tumor activities in animal and human studies. The aim of this study was to determine the anti-inflammatory activities of an 80% methanol extract(CE-Met), hexane fraction (CE-Hex), and ethyl acetate fraction (CE-EA) of Chlorella ellipsoidea in lipopolysaccharide (LPS)-stimulated RAW 264.7 murine macrophage. Treatment with various concentrations of the C. ellipsoidea extract resulted m a significant, dose-dependent reduction in nitric oxide (NO) production by LPS-induced macrophages. The C. ellipsoidea extract significantly inhibited LPS-induced NO production accompanied by an attenuation of IL-6 and TNF-$\alpha$ formation in macrophages. These results suggest potent inhibit이y effects on the production of inflammatory mediators by a C. ellipsoidea extract. Thus, C. ellipsoidea extract may be a potent anti-inflammatory agent for troubled skin.

• Journal of Microbiology and Biotechnology
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• v.25 no.7
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• pp.1093-1100
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• 2015

Acetate and lactate in growth media are detrimental to the production of Thermus maltogenic amylase (ThMA), a heterologous protein, as well as to the growth of recombinant Escherichia coli. Only 50 mM of acetate or 10 mM of lactate reduced 90% of specific ThMA activity. In this study, mutant E. coli strains blocked in the ackA-pta or ackA-pta and ldh pathways were created, characterized, and assessed for their culture performace in 300 L-scale fermentation. The ackApta and ldh double-mutant strain formed significantly less lactate and acetate, and produced a concomitant increase in the excretion of pyruvate (17.8 mM) under anaerobic conditions. The ackA-pta mutant strain accumulated significant acetate but had an approximately 2-fold increase in the formation of lactate. The ackA-pta and ldh double-mutant strain had superior overall performance in large-scale culture under suboptimal conditions, giving 67% higher cell density and 66% higher ThMA activity compared with those of the control strain. The doublemutant strain also achieved a 179% improvement in volumetric ThMA production.

• Environmental Engineering Research
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• v.11 no.2
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• pp.91-98
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• 2006

There is a possibility of the production of the air bubbles in membrane pores due to the reduction in pressure during membrane filtration. The effect of fine air bubbles from dissolved gases on microfiltration was investigated in the submerged membrane bio-reactor (SMBR). The $R_{air}$ (air bubble resistance) was defined as the filtration resistance due to the air bubbles formed from the gasification of dissolved gases. From the results of filtration tests using pure water with changes in the dissolved oxygen concentration, the air bubbles from dissolved gases were confirmed to act as a foulant and; thus, increase the filtration resistance. The standard pore blocking and cake filtration models, SPBM and CFM, respectively, were applied to investigate the mechanism of air bubble fouling on a hollow fiber membrane. However, the application of the SPBM and CFM were limited in explaining the mechanism due to the properties of air bubble. With a simple comparison of the different filtration resistances, the $R_{air}$ portion was below 1% of the total filtration resistance during sludge filtration. Therefore, the air bubbles from dissolved gases would only be a minor foulant in the SMBR. However, under the conditions of a high gasification rate from dissolved gases, the effect of air bubble fouling should be considered in microfiltration.

• Journal of Korean Society of Rural Planning
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• v.23 no.2
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• pp.75-86
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• 2017

IPCC Guidelines have been updated after the first official announcement to get more precise estimation of GHG emissions. The goal of this study is to evaluate the implications of the IPCC Guidelines improvements including equations of country-specific parameter values for estimating GHG emissions for rice cultivation on the agricultural sector. In addition, we analyze the effects of emission factors associated with organic amendment applications. The results of this study are as follows; (1) the total GHG emissions of rice cultivation based on 1996 IPCC GL are 28% lower than those estimated by 2006 IPCC GL with the same year data; (2) GHGs can be reduced up to 60% through the assumption of organic fertilizer applications; (3) Jeonnam and Chungnam are the worst regions for GHG emissions on rice cultivation and Chungbuk shows the highest reduction rate of GHG emissions, about 40%.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.31 no.4
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• pp.334-338
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• 2009

Supernumerary teeth are extra teeth or tooth-like structures which may have either erupted or unerupted in addition to the 20 deciduous teeth and the 32 permanent teeth. Clinicians sometimes confront unerupted supernumerary teeth where implants would be placed. Many clinicians consider immediate placement of implant into an extracted socket as an effective technique compared to the conventional method of waiting several months for bone healing, because of the advantages such as reduction of treatment period, preservation of alveolar bone and soft tissue, etc. We could hardly find the case of immediate placement of implant after extraction of impacted supernumerary teeth and permanent teeth together. Therefore we report the case of immediate implantation following extraction of impacted supernumerary teeth and poor periodontal conditioned permanent teeth.

• Imaging Science in Dentistry
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• v.30 no.4
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• pp.265-274
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• 2000

Purpose: The aims of the present study are to determine the optimum compression rate in terms of file size reduction and diagnostic quality of the images after compression and evaluate the transmission speed of original or each compressed image. Materials and Methods: The material consisted of 24 extracted human premolars and molars. The occlusal surfaces and proximal surfaces of the teeth had a clinical disease spectrum that ranged from sound to varying degrees of fissure discoloration and cavitation. The images from Digora system were exported in TIFF and the images from conventional intraoral film were scanned and digitalized in TIFF by Nikon SF-200 scanner (Nikon, Japan). And six compression factors were chosen and applied on the basis of the results from a pilot study. The total number of images to be assessed were 336. Three radiologists assessed the occlusal and proximal surfaces of the teeth with 5-rank scale. Finally diagnosed as either sound or carious lesion by one expert oral pathologist. And sensitivity, specificity and k value for diagnostic agreement was calculated. Also the area (Az) values under the ROC curve were calculated and paired t-test and oneway ANOVA test was performed. Thereafter, transmission time of the image files of the each compression level was compared with that of the original image files. Results: No significant difference was found between original and the corresponding images up to 7% (1 : 14) compression ratio for both the occlusal and proximal caries (p<0.05). JPEG3 (1 : 14) image files are transmitted fast more than 10 times, maintained diagnostic information in image, compared with original image files. Conclusion: 1 : 14 compressed image file may be used instead of the original image and reduce storage needs and transmission time.