• Journal of Digital Contents Society
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• v.14 no.2
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• pp.255-262
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• 2013

Useful applications for English education enable immediate conversion of mobile devices into remote wireless systems for classroom computers. Once the free software has been installed in the main computers in the classroom, using powerpoint, students can operate the computers through their mobile devices by installing Air mouse on them. By using this, the students can draw or write on the "board" to manipulate the educational resources from where they are/from their seats. The study of English language encompasses not only academic study but also language training. Until recently, the issue of the English language learning has been ridden with certain problems-instead of being a tool that facilitates communication, its main purpose has been for school grades, TOEIC, and TOEFL. This study suggests English language learning methodology using various applications such as mobile, VOD English language content, and movie scripts in implementing easy and fun English language learning activities that can be studied regularly. This is operationalized by setting a specific limit on learning and by using various media such as podcast, Apps, to increase interest, motivation, and self-directed learning in a passive learning environment.

• Journal of the Korean Geotechnical Society
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• v.15 no.2
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• pp.43-71
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• 1999

This research is an experimental work of developing a construction material using municipal wastewater sludge as liner and cover materials for waste disposal landfill. Weathered granite soil and flyash, produced as a by-product in the power plant, were used as the primary additives to improve geotechnical engineering properties of sludge. For secondary additives, bentonite and cement were mixed with sludge to decrease the permeability and to increase the shear strength, respectively. Various laboratory test required to evaluate the design criteria for liner and cover materials, were carried out by changing the mixing ratio of sludge with the additives. Basic soil properties such as specific gravity, grain size distribution, liquid and plastic limits were measured to analyze their effects on permeability, compaction, compressibility and shear strength properties of mixtures. Laboratory compaction tests were conducted to find the maximum dry densities and the optimum moisture contents of mixtures, and their effectiveness of compaction in field was consequently evaluated. Permeability tests of variable heads with compacted samples, and the stress-controlled consolidation tests with measuring permeabilities of samples during consolidation process were performed to obtain permeability, and to find the compressibility as well as consolidational coefficients of mixtures, respectively. To evaluate the long term stability of sludges, creep tests were also conducted in parallel with permeability tests of variable heads. On the other hand, for the compacted sludge decomposed for a month, permeability tests were carried out to investigate the effect of decomposition of organic matters in sludges on its permeability. Direct shear tests were performed to evaluate the shear strength parameters of mixed sludge with weathered granite, flyash and bentonite. For the mixture of sludge with cement, unconfined compression tests were carried out to find their strength with varying mixing ratio and curing time. On the other hand, CBR tests for compacted specimen were also conducted to evaluate the trafficability of mixtures. Various test results with mixtures were assessed to evaluate whether their properties meet the requirements as liner and cover materials in waste disposal landfill.

• Journal of Korean Society of Forest Science
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• v.87 no.2
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• pp.286-299
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• 1998

This study was conducted to do a comparative analysis of hunting system in 16 OECD(Organization for Economic Co-operation and Development) countries. Hunting is one of the most advanced types for developing natural resources, esp. wildlife, which is one of major products from forest. There are two types of hunting system ; Revier and/or License System, around most countries which have traditional advanced hunting and higher hunter population. Licence system, which is chosen in Korea, is less efficient ways of hunting for maximizing economical value and wildlife management than Revier system does. Adopting better system for much more efficient economical condition from hunting in Korea in a future is a ultimate goal in this study. The first step for the goal is an analysis of these two system among 16 OECD countries ; United State, Japan, Germany, France, etc. Comparative researches in hunting regulations such as number of hunters, hunter ratio to population, hunting bags, game species, seasons, ammunition and hunting permit are a next step for adopting developed hunting system in Korea. Korea has a smallest hunter ratio to population (1/2,463) among 16 OECD centuries and economical value lead by hunting is estimated still very low. Revier system is a popular one in most OECD countries except United State, Japan, etc, which is useful for wildlife management and maximizing economical value of hunting. And usually rifles are permitted for big game hunting. Hunting examination and/or insurance are compulsory for achieving hunting permit. Depend on game species, yearly hunting bag and season are constructed in most OECD countries.

• Geotechnical Engineering
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• v.9 no.3
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• pp.49-60
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• 1993

The compatibility of chemicals in the leachates with the three natural and artificially -made liner materials is analyzed by performing the laboratory hydraulic conductivity test. The selected liner materials are natural marine clay, fly ash and weathered granitic soil stomped from Kimpo Wastefills, Seochon power plant and Mansu Dong, Inchon, respectivaly. Bentonites of 20 and 10 percent by weight are used as additive materials for fly ash and weathered granitic soil and the chemical solutions used in the test are acetic acid, methanol, heptane, and aniline which are frequently found in the leachate of waste fills. The concentrations of the chemical solutions are 100% and 75%. The results of the tests show that hydraulic conductivities of the oxter materials are increased by one or two orders of magnitude with permeating pure chemical solutions. The rate of hydraulic conductivity increase is lowest for Seochon fly ash admixed liner and highest for natural marine clay liner. The influence of hydraulic chemical solutions on the liner materials is least for acetic acid and largest for aniline. The increases of conductivity are not shown with the permeation of the solution of concentration 75%. At least by this test results, it can be recognized that the tested liner material can be quite stable with the solutions of significantly high concentration except pure solutions.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.52 no.2
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• pp.146-152
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• 2007

The present study was carried out to investigate the potential acute toxicity of ethanol extracts of the aleurone layer of Oryza sativa cvs. Obongbyeo, Ilpumbyeo, and Aranghyangchalbyeo by a single oral dose in ICR mice. The test article was orally administered once by gavage to male and female mice at dose levels of 0, 2.5, 5.0, and 10.0 g/kg body weight (n=10 for male and female mice for each dose). We examined numbers of deaths, general signs, weight measurement and biochemical analysis for sexes and doses of mice control and experimental groups. All mice were alive during the experimental period so can not yield death rate and $LD_{50}$. Any significant clinical symptom was not observed in all treated groups. No significant body weight changes in treatment groups in comparison with those of control groups was observed at any dose levels in experimental groups. Plasma glucose levels were valued both control and treated groups and there were no significant differences between groups. The activities of ALT and AST were not increase in all sample treated groups when compared with the control groups. The results suggest that the toxicity of Oryza sativa cvs. Obongbyeo, Ilpumbyeo, and Aranghyangchalbyeo are low and its $LD_{50}$ is over 10.0 g/kg body weight in both male and female mice.

• Proceedings of the KSR Conference
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• 2007.11a
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• pp.551-557
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• 2007

This paper describes a study on the permeability reduction of the riverbed ground during urban railway tunnel construction. The research is mainly concentrated on the study of the grouting or injection methods among permeability reduction methods which can be adapted in the riverbed ground. Firstly, the various grouting methods are theoretically reviewed and compared based on the previous research papers and case study results. It is also evaluated the grouting methods in view of a safe construction of the river crossing railway tunnel. Baced on the literature review and previous construction data, the design technology of grouting methods considering the long term hydro-geological behaviour in the riverbed, is suggested. Two injection methods namely, Natural Durable Stabilizer(N.D.S) and Space-Multi Injaction Grouting(S.M.I) methods, are introduced as new approach methods which can be adopted to modify the riverbed ground. In order to evaluate the ground that grouted and modified by the N.D.S and S.M.I method, the pilot test programmes including the field and laboratory permeability tests, are carried out in the river crossing tunnel construction sites. The results obtained from pilot test programme, are also reviewed. In conclusion, the grouting efficiency of the S.M.I method using the non-alcalimeter silica sol is better than that of NDS method using cement. In addition, it hopes that the research results are contributed to develop the grouting design technology.

• Journal of Animal Science and Technology
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• v.45 no.1
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• pp.69-78
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• 2003

This experiment was carried out to evaluate the value of total mixed fermentation feeds(TMFF) as completely mixed ration and to observe the effect of various kinds of TMFF on the palatability, feed intake, and milk performance in Holstein cows. The dry matter (DM) content of TMFF used in the experiment was 23.98-28.42% range, and CP, TDN, ADF and NDF were 16.2${\sim}$19.2%, 58.3-65.1%, 34.4-39.6% and 46.9${\sim}$49.9% levels, respectively. The relative feed value (RFV) in rape-, alfalfa-, grass-, oat-, corn-TMFF groups were 138.6, 133.9, 116.5, 111.8, 111.4 and 108.1, respectively. Among these groups, RFV of rye-TMFF group was lowest. Dry matter disappearance(DMD) showed 0.8${\sim}$.9% to the all kinds of TMFF groups. The pH was 3.89${\sim}$.87 and $NH_3$-N concentration was 6.93-8.66 mg/$d\ell$. The acetic acid concentration in the raw material of TMFF showed low level of 0.19${\sim}$0.57%, lactic acid showed high level of 1.17${\sim}$3.21% and butyric acid was very high as 0.03${\sim}$0.32%. Therefore, these results provide evidence that the quality of TMFF was not so bad. In the daily fresh matter intake on the alfalfa-, grass-, rape-, corn-, oats- and rye-TMFF were showed 62.85, 60.48, 58.04, 57.11, 54.61 and 45.74 kg respectively. All TMFF showed high palatability as daily dry matter intake of 1.95 to 2.90% by body weight of experimental cows. Body condition score(BCS) was gradually increased in during 60 days of the experiment term. Average daily gain(ADG) showed about 140.0${\sim}$326.7g. In alfalfa-TMFF group, the ADG was higher than in the other groups (p<0.05). Also, the increase in BCS was observed in grass-TMFF group (3.07 to 3.34) and rye-TMFF group was decreased in 3.07 to 3.34 (p<0.05). The milk yield appropriately showed a range of 16.16${\sim}$18.95 kg in all groups. Among these groups, alfalfa-TMFF group was highest(P<0.05). Average milk fat contents showed high levels of 4.06${\sim}$4.79% and the level was high in order of rape-, grass-, corn-, alfalfa-, rye- and oats-TMFF. Milk protein was highest in forage-TMFF and level of lactose in milk was approximately 4.56% in overall groups. Solid non fat(SNF) and total solid(TS) contents were 8.75% and 12.8%, respectively. However, milk composition was not significantly affected by TMFF.

• Journal of the Korea Organic Resources Recycling Association
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• v.10 no.3
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• pp.59-67
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• 2002

This study was carried out to improve the utilization of food wastes known as major source of environmental pollution and to determine proper additional levels of methionine hydroxy analogue(MHA) on food wastes. 1%, 3% and 5% of MHA were added to 3 groups of food wastes gathered from small cafeteria. Each group has 3 reiteration. NaCl contents were tended to get higher as addition levels increased(p<0.05). And pH values were tended to get lower as additional levels increased(p<0.05). $NH_3-N$ contents were significantly decreased as additional levels increased(p<0.05). Total VFA(Volatile Fatty Acid) content was increased after 30 days of storage on control. On MHA treatments(1, 3, 5%), total VFA contents were decreased until 15 days of storage, and kept low values until the end of experiment. In terms of superficial change, mildew covered all over control, and covered by thin mildew on the surface of 1% MHA treatment. No superficial change found on 3% and 5% MHA treatments. In conclusion, over 1% addition of MHA was effective to prevent the decay and degeneration of food wastes.

• Journal of Animal Science and Technology
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• v.47 no.6
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• pp.947-954
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• 2005

This study was conducted to investigate the effects of hydrolyzed Lactobacillus supplementation with digestive enzymes treatment on the macrophage activation, the induction of nitric oxide(NO), interleukin (IL)-6 and tumor necrosis factor(TNF)-$\alpha$. The RAW 264.7 murine macrophage was exposed to porcine Lactobacillus strains which were digested with both pepsin and pancreatin. The production of NO, TNF-$\alpha$ and IL-6 in the macrophage were strain and dose-dependent, respectively. The induction of NO and cytokines were higher in both 3149 and 3146 strains compared with other Lactobacillus strains. Overall, the level of NO was observed at the lower range between 10 and 150 μg hydrolysates per ml, whereas IL-6 and TNF-$\alpha$ were observed at relatively higher concentration between 50 and 300 μg hydrolysates per ml. Lactobacillus strains which produced a high level of NO also showed a high induction of TNF-$\alpha$ and IL-6. Therefore, the present results suggest that hydrolysates of Lactobacillus strains are related to induction of several macrophage mediators, and then it could be beneficially used to modulate gastrointestinal immune function of the host. Also, the methodogly employed in this study might be useful to investigate the effects of lactic acid bacteria on gastrointestinal immunity.

• International Journal of Highway Engineering
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• v.6 no.4 s.22
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• pp.13-24
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• 2004

The Marshall mix design method used in Korea, which was described in the design & construction regulation, had been introduced from Japan Highway Cooperation standard guide. Most engineers have thought that it is the major reason that causes pavement distresses. Therefore, there is a need to modify the current Marshall mix design through using the volumetric design concept, which is most widely used in asphalt mix design. The modified mix design determines the preliminary optimum asphalt content at 4% VTM (Voids in Total Mix). If the Marshall properties, which are VFA, VMA, stability, and flow, were satisfied with the requirements, the preliminary optimum asphalt content is determined as the final optimum asphalt content. The modified Marshall mix design considers VMA. while the current Marshall mix design does not consider VMA. By considering the Marshall stability and flow as the criteria instead of design factors, the modified Marshall mix design is able to decrease the errors occurred in Marshall stability test The test was performed to compare the Marshall properties between current and modified Marshall mix design. The left results showed that there was no difference in the Marshall properties, except for VTM. Thus, the modified Marshall mix design can produce the asphalt mixtures with the constant VTM (4%), and it can improve the asphalt mixture quality in Korea.