• Journal of Life Science
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• v.24 no.10
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• pp.1110-1117
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• 2014

Tidal flats are continuously contaminated by human activities. This study assessed the bioremediation efficiency of tidal flat soil using microcosm reactors and microorganisms originating from the tidal area. We screened 135 bacterial strains that produce extracellular enzymes from the tidal area located in the North port of Incheon bay. Two bacterial strains (Pseudoalteromonas sp. and IC35 Halothiobacillus neapolitanus IC_S22) were selected and used in the microcosm reactors, which were specially designed to functionally mimic the ecological conditions of the tidal flats. Pseudoalteromonas sp. IC35 was selected based on its relatively high activity of the enzymes amylase, cellulose, lipase, and protease. Halothiobacillus neapolitanus IC_S22 was selected for oxidation of sulfur. The M1 and M2 microcosm reactors were operated by continuous feeding of seawater under the same conditions, but M2 was first inoculated with Pseudoalteromonas sp. IC35 before the seawater feeding. The initial COD in both the M1 and M2 microcosm reactors was 320 mg/l. The final COD was 21 mg/l (M1) and 7 mg/l (M2). The M3 and M4 microcosm reactors were operated by continuous feeding of seawater under the same conditions, but M4 was first inoculated with H. neapolitanus IC_S22. The initial sulfate concentration in both the M3 and M4 microcosm reactors was 660 mg/l, and the maximum sulfate concentration was 1,360 mg/l (M3) and 1,600 mg/l (M4).

• Journal of Gifted/Talented Education
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• v.22 no.1
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• pp.1-21
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• 2012

The objective of this study is to suggest improvement plan for invention gifted education based on the awareness of teachers and professionals who related to the invention gifted education for the expansion and development of invention gifted education through improvement of relevant problems. To this end, invention gifted education system and its operational status were analyzed, and questionnaire survey on the awareness of the development plan and satisfaction level was conducted, targeting professionals related to the invention gifted education and teachers in charge of invention gifted education classes or gifted education center. The research results are as follows. First, the level of satisfaction on the invention gifted education was greater than normal (M=3.0) in general, but in the field of 'educational materials', 'teacher training programs' and 'human and material support system of support agencies', the level of satisfaction was relatively low, which requires expansion of the support. Second, it is necessary for Korean Intellectual Property Office and Korea Invention Promotion Association to designate and establish specialized research institution to play a key role in enhancing development and efficiency of invention gifted education. As a result of the questionnaire survey, it turned out that expectation and necessity of the specialized research agency was highly recognized. In particular, demand for 'research and development of gifted education method and materials' and 'research and development of teacher training materials and implementation of teacher training' was high among the key areas of the specialized research institution. Third, teachers and professionals related to the invention gifted education responded that 'invention knowledge' in the areas of invention knowledge and thinking and 'entrepreneurship' in the area of invention attitude was somewhat low toward the question on the level of the 9 characteristics of gifted students with invention talents which current beneficiaries of invention gifted education have, which leads to conclusion that review on the model for the selection of gifted children with invention talents as well as research and development of invention gifted education program to enhance characteristics with low levels is required. If long-term development plans and initiatives are deduced based on this, an effective framework for the invention gifted education will be established in the near future. In addition, it is expected that the differentiated political visions and goals will be established in connection with master plan for the promotion of gifted education.

• Journal of The Korean Society of Grassland and Forage Science
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• v.18 no.3
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• pp.171-178
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• 1998

This experiment was conducted to study on forage utility of Diplachne fusca L. which live in reclaimed saline land of midwest region of Korea. The primary experiment was conducted to know on germination characteristics of Diplachne fusca L. according to storage condition after seed harvesting, light, temperature, flooding depth, salinity and soil covering. The results obtained are summarized as follows; 1. The germination percentage, average days to germination, germination rate and coefficient of germination were not different in existence of light, combination with existence of light and storage condition, but those were higher different in storage condition. 2. The germination characteristics were more higher on the condition of alternating temperature than constant temperature, and it was the highest on the condition of alternating temperature with $35/25^{\circ}C$ and constant temperature with $35^{\circ}C$. 3. There were apparently significant in germination percentage, average days to germination, germination rate and coefficient of germination according to flooding depth. The germination characteristics of D. fusca L. were the highest on the wndition of flooding depth with Ocm and did not germinate on the condition of flooding depth more than 3cm. 4. There were apparently significant in germination percentage, average days to germination, germination rate and coefficient of germination according to salinity. Germination characteristics were the highest on the condition of salinity with 0.2%. There was more than 30% of germination percentage on the condition of salinity with 1% SO Diplachne fuaca L. was suitable to cultivate in reclaimed saline land. 5. The germination percentage, average days to germination, germination rate and coefficient of germination were significantly difference between soil covering. So Germination characteristics were the highest on the condition of soil covering with 0.2cm. But they scarcely germinated on the condition of more than 1cm of the soil covering.

• Proceedings of the Korea Society of Poultry Science Conference
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• 2002.11a
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• pp.124-125
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• 2002

Two experiments were conducted to investigate the response of chitosan supplementation in diet on the major economic traits of broiler in two different breeds. In the both experiments, the Arbor Acres and Ross breeds were used as experimental stocks and two groups were assigned in each breed. The control group birds(CON) were fed with basal diet only and the experimental group birds(EXP) were fed with basal diet added with 10.5mg chitosan/bird/day. The chitosan was supplied to birds from day-old in experiment 1 and from 15-day-old in experiment 2. In experiment 1, the mean body weight at 35-day-old were significantly(P〈0.05) heavier by 121.2 g and 243.7 g in the EXP groups than in the CON groups of Arbor Acres and Ross, respectively. Whereas, the mean body weights at 35-day-old in experiment 2 were lighter by 91.7 g and 70.2 g in the EXP groups than in the CON groups of Arbor Acres and Ross, respectively : however, the comparisons between breeds in the mean body weight at 35-day-old did not show significant difference in each other in both breeds. In the mean feed conversion ratio of Arbor Acres from 14 to 35-day old in experiment 1, it did not show significant difference between EXP and CON groups although the feed conversion ratio of the EXP group of Ross was significantly higher(P〈0.05) than the CON group. In experiment 2, the feed conversion ratios from 14 to 35-day-old did not show significant differences between the two breeds. The percentage of mean abdominal fat depositions of EXP groups in both breeds In experiment 1 were significantly(P〈0.05) higher than those of CON groups. And the percentage of mean abdominal fat deposition of Ross was significantly(P〈0.05) lower than that of Arbor Acres. In experiment 2, the percentage of mean abdominal fat depositions did not show significant difference between EXP and CON groups in both breeds. Whereas, the interaction effects between breed and experimental groups on the above economic traits did not show significant in both experiments.

• Korean Journal of Poultry Science
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• v.12 no.1
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• pp.17-24
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• 1985

In order to investigate an effect of non-protein nitrogen on the biological utilization of protein, hatched single comb White Leghorn male chicks were fed for the first 8 days with a commercial chicks mash, next 6 days with protein-free diet and subsequent 6 days with protein-free diets and protein diets containing 10.59% of crude protein supplemented with 0, 0.5, 1.0 and 1.5%, respectively. During experimental feeding period, chicks fed protein-free diets had intaked gradually lower feed and had shown a similar body weight loss though urea contents were increased. When birds fed protein diets, body weight gain and feed intake were not different among birds fed the graded levels of urea although feed conversions were shown a highering tendency along with increasing urea contents. According as supplemented urea were increased, protein efficiency ratio f (PER) and net protein ratio (NPR) were increased in chicks fed protein-free diets, which were shown a lowering trend in chicks fed protein diets. Effect of supplemented urea on the urinary excretion of uric acid were not found in birds fed protein-free diets, while which were increased in birds fed protein diets with the increase of urea contents. Urea addition did not affect the excretion of total creatine in birds fed protein-free or protein diets. Excretion of ammonia was jogjered in order to increasing level of urea in birds fed protein-free diets, but which were not found any particular effect in birds fed protein diets. Also urea excretion were gradually increased with the increasing contents of urea in protein-free and protein diets. Nitrogen balance of birds fed protein-free diets were minus values, which were increased with increasing urea contents in diets. When birds fed protein diets, nitrogen balance and urinary nitrogen excretion was highered and fecal nitrogen excretion were not altered as urea levels of diets increased. Digestibility of urea nitrogen supplemented in protein-free diets were lowered along with increasing contents of urea, but biological value(BV) and net protein utilization(NPU) was found a highering tendency in birds fed protein-free diet containing 1.5% of urea. When birds fed with protein diets, digestibility, BV and NPU of protein were found a highering trend in birds fed protein diets added with 0.5% of urea.

• Journal of Soil and Groundwater Environment
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• v.11 no.1
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• pp.14-22
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• 2006

Laboratory column experiment for simultaneous removal of Cd and Cr(VI) were conducted using newly developed material of Fe-loaded zeolite having both reduction ability and sorption capacity. The solution containing Cd and Cr(VI) was injected into the column and the breakthrough curves (BTCs) for the contaminants were observed at the effluent port. Cd breakthrough was not initialized until Cr(VI) breakthrough was completed. Therefore it could be concluded that overall efficiency of Fe-loaded zeolite should be determined by the reactivity for Cr(VI). The relative concentration of Cr(VI) BTC increased to the unit value while initial breakthrough was delayed and the propagation of breakthrough was slowed. In order to quantitatively describe the shape of Cr(VI) BTC, new parameters of ${\alpha}\;and\;{\beta}$ designated to be shape parameters, were defined and applied in contaminant transport concentration. These parameters were employed to represent the degree of initial breakthrough delay and the degree of breakthrough propagation, respectively. As initial contaminant concentration increased, ${\alpha}$ decreased, which indicated the delay of BTC's initiation. And as initial contaminant flow rate increased, ${\beta}$ decreased, which represented the faster propagation of the BTC. From these results, Fe-loaded zeolite was found to be an effective reactive material for PRBs against heavy metals having different ionic forms in groundwater. And it could be expected that as groundwater flows faster, the propagation of breakthrough would be faster and as contaminant concentration is higher, the initial point of breakthrough would appear earlier.

• Journal of Technology Innovation
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• v.26 no.3
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• pp.37-68
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• 2018

Since the 20th century, automobiles, which are the most common means of transportation, have been evolving as the use of electronic control devices and automotive semiconductors increases dramatically. Automotive semiconductors are a key component in automotive electronic control devices and are used to provide stability, efficiency of fuel use, and stability of operation to consumers. For example, automotive semiconductors include engines control, technologies for managing electric motors, transmission control units, hybrid vehicle control, start/stop systems, electronic motor control, automotive radar and LIDAR, smart head lamps, head-up displays, lane keeping systems. As such, semiconductors are being applied to almost all electronic control devices that make up an automobile, and they are creating more effects than simply combining mechanical devices. Since automotive semiconductors have a high data rate basically, a microprocessor unit is being used instead of a micro control unit. For example, semiconductors based on ARM processors are being used in telematics, audio/video multi-medias and navigation. Automotive semiconductors require characteristics such as high reliability, durability and long-term supply, considering the period of use of the automobile for more than 10 years. The reliability of automotive semiconductors is directly linked to the safety of automobiles. The semiconductor industry uses JEDEC and AEC standards to evaluate the reliability of automotive semiconductors. In addition, the life expectancy of the product is estimated at the early stage of development and at the early stage of mass production by using the reliability test method and results that are presented as standard in the automobile industry. However, there are limitations in predicting the failure rate caused by various parameters such as customer's various conditions of use and usage time. To overcome these limitations, much research has been done in academia and industry. Among them, researches using data mining techniques have been carried out in many semiconductor fields, but application and research on automotive semiconductors have not yet been studied. In this regard, this study investigates the relationship between data generated during semiconductor assembly and package test process by using data mining technique, and uses data mining technique suitable for predicting potential failure rate using customer bad data.

• Journal of Wetlands Research
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• v.21 no.spc
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• pp.98-106
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• 2019

The coefficient and exponent of the MUSLE(Modified Universal Soil Loss Equation) runoff factor in the SWAT(Soil and Water Assessment Tool) model are 11.8 and 0.56 respectively, which are equally applied to the estimation of soil erosion regardless of land use. they could derive overestimation or underestimation of soil erosion, which can cause problems in the selection of soil erosion-vulnerable area and evaluation of reduction management. However, there are no studies about the estimation of coefficients and exponent for the MUSLE runoff factor by land use and their applicability to the SWAT model. Thus, in order to predict soil erosion and sediment behavior accurately through SWAT model, it is necessary to estimate the coefficient and exponent of the MUSLE runoff factor by land use and evaluate its applicability. In this study, the coefficient and exponent of MUSLE runoff factor by land use were estimated for Gaa-cheon Watershed, and the differences in soil erosion and sediment from SWAT model were analyzed. The coefficient and exponent of runoff factor estimated by this study well reflected the characteristics of soil erosion in domestic highland watershed. Therefore, in order to apply the MUSLE which developed based on observed data of US agricultural basin to the domestic watershed, it is considered that a sufficient modification and supplementation process for the coefficient and exponent of the MUSLE runoff factor depending on land use is necessary. The results of this study can be used as a basic data for selecting soil erosion vulnerable area in the non-point source management areas and establishing and evaluating soil erosion reduction management.

• Journal of the Korean Society of Food Culture
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• v.17 no.1
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• pp.30-36
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• 2002

The effects of Bamboo(Pseudosasa japonica Maki) extracts on serum lipid concentrations were evaluated in rats. Ninety-eight male Sprague-Dawley rats weighing $100{\pm}10g$ were divided into fourty groups and fed high fat diets for four weeks. Experimental groups were administered with following diets; basal fat diet(control), basal and high fat diets with 1% cholesterol and Bamboo(Pseudosasa japonica Maki, -1%, -3%, -5%) extracts. The concentrations of serum triglyceride in rats fed the Bamboo(Pseudosasa japonica Maki) extract, high fat, 1% cholesterol, and Pseudosasa japonica Maki, -1%, -3%, -5% were lower than those in other groups. The concentrations of total cholesterol in the Pseudosasa japonica Maki, -1%, -3%, -5% groups were lower than those in fat diet groups. The concentrations of HDL-cholesterol in serum of the Pseudosasa japonica Maki, -1%, -3%, -5% groups were significantly higer than those of other groups. The levels of LDL-cholesterol in serum of the Pseudosasa japonica Maki, -1%, -3%, -5% groups were tended to be lower than those of other groups. These results suggest that Bamboo(Pseudosasa japonica Maki) extract may reduce elevated levels of serum lipid concentrations in rats fed high fat diets.

• Korean Journal of Environmental Agriculture
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• v.27 no.3
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• pp.225-230
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• 2008

Objective of this study was to access the environmental impacts of the use of discharge water from municipal waste water treatment plant as alternative irrigation resources during drought season for rice cultivation. For the field experiments, it was observed that plant growth and yield characteristics at 20 days of alternative irrigation period with application of FAST (fertilizer application based on soil test) 50% were relatively the same as the control. For the surface water quality, it appeared that $EC_i$ (electrical conductivity of irrigation water) and SAR (sodium adsorption ratio) values of DMWT (discharge waters from municipal wastewater treatment plant) irrigation were twofold higher than those of ground water irrigation as the control regardless of fertilization levels. For the irrigation periods, there were not significantly difference between 10 and 20 days of treatments, but $EC_i$ and SAR values of surface water were highest at 30 days of irrigation periods at initial rice growing stages. Generally, $EC_i$ values of percolation water in all the treatments were gradually increasing until 30days after irrigation, and then decreasing to harvest stage. Overall, it might be considered that there was possibility to irrigate DMWT with application of FAST 50% for 20 days of drought periods at rice transplanting season. Furthermore, efficiency rate of alternative irrigation water for 20 days of drought period was 32.7% relative to the total annual irrigation water for rice cultivation.