• Asian-Australasian Journal of Animal Sciences
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• v.29 no.9
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• pp.1345-1352
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• 2016

The hindgut of horses is an anaerobic fermentative chamber for a complex and dynamic microbial population, which plays a critical role in health and energy requirements. Research on the gut microbiota of Mongolian horses has not been reported until now as far as we know. Mongolian horse is a major local breed in China. We performed high-throughput sequencing of the 16S rRNA genes V4 hypervariable regions from gut fecal material to characterize the gut microbiota of Mongolian horses and compare them to the microbiota in Thoroughbred horses. Fourteen Mongolian and 19 Thoroughbred horses were used in the study. A total of 593,678 sequence reads were obtained from 33 samples analyzed, which were found to belong to 16 phyla and 75 genera. The bacterial community compositions were similar for the two breeds. Firmicutes (56% in Mongolian horses and 53% in Thoroughbred horses) and Bacteroidetes (33% and 32% respectively) were the most abundant and predominant phyla followed by Spirochaete, Verrucomicrobia, Proteobacteria, and Fibrobacteres. Of these 16 phyla, five (Synergistetes, Planctomycetes, Proteobacteria, TM7, and Chloroflexi) were significantly different (p<0.05) between the two breeds. At the genus level, Treponema was the most abundant genus (43% in Mongolian horses vs 29% in Thoroughbred horses), followed by Ruminococcus, Roseburia, Pseudobutyrivibrio, and Anaeroplasma, which were detected in higher distribution proportion in Mongolian horses than in Thoroughbred horses. In contrast, Oscillibacter, Fibrobacter, Methanocorpusculum, and Succinivibrio levels were lower in Mongolian horses. Among 75 genera, 30 genera were significantly different (p<0.05) between the two breeds. We found that the environment was one of very important factors that influenced horse gut microbiota. These findings provide novel information about the gut microbiota of Mongolian horses and a foundation for future investigations of gut bacterial factors that may influence the development and progression of gastrointestinal disease in horses.

• Journal of Korean Tunnelling and Underground Space Association
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• v.2 no.2
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• pp.50-61
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• 2000

The ground around the portal of a tunnel is the most typical part showing the 3-dimensional mechanical behavior in the tunnel. The portal slope is constructed at the weathered soft rock-mass, and remains as a potential sliding mass. The slope failure around the tunnel portal may happen drastically and induce the great disaster; hence, for the permanent stability several special techniques are required. To solve this problem, the ground around the tunnel portal may be excavated in the arch shape to develop the arching effect in horizontal direction. With the arch-type portal slope, one can reduce considerably the excavation mass and the damage of environments. This approach has not been attempted yet due to the lack of understanding and the well-defined analyzing method, so the retaining wall type portal is more universal. The 3-dimensional finite element analyses were carried out to prove that the arch type is more advantageous in safety and cost than the right angle type. The influence of the tunnel construction sequence and the strength of the rock-mass on the slope stability was investigated by focusing on the maximum shear strain in the slope, and the yield zone at the tunnel face.

• Asian-Australasian Journal of Animal Sciences
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• v.31 no.10
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• pp.1535-1541
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• 2018

Objective: In birds, three types of melatonin receptors (MTNR1A, MTNR1B, and MTNR1C) have been cloned. Previous researches have showed that three melatonin receptors played an essential role in reproduction and ovarian physiology. However, the association of polymorphisms of the three receptors with duck reproduction traits and egg quality traits is still unknown. In this test, we chose MTNR1A, MTNR1B, and MTNR1C as candidate genes to detect novel sequence polymorphism and analyze their association with egg production traits in Shaoxing duck, and detected their mRNA expression level in ovaries. Methods: In this study, a total of 785 duck blood samples were collected to investigate the association of melatonin receptor genes with egg production traits and egg quality traits using a direct sequencing method. And 6 ducks representing two groups (3 of each) according to the age at first eggs (at 128 days of age or after 150 days of age) were carefully selected for quantitative real-time polymerase chain reaction. Results: Seven novel polymorphisms (MTNR1A: g. 268C>T, MTNR1B: g. 41C>T, and g. 161T>C, MTNR1C: g. 10C>T, g. 24A>G, g. 108C>T, g. 363 T>C) were detected. The single nucleotide polymorphism (SNP) of MTNR1A (g. 268C>T) was significantly linked with the age at first egg (p<0.05). And a statistically significant association (p<0.05) was found between MTNR1C g.108 C>T and egg production traits: total egg numbers at 34 weeks old of age and age at first egg. In addition, the mRNA expression level of MTNR1A in ovary was significantly higher in late-mature group than in early-mature group, while MTNR1C showed a contrary tendency (p<0.05). Conclusion: These results suggest that identified SNPs in MTNR1A and MTNR1C may influence the age at first egg and could be considered as the candidate molecular marker for identify early maturely traits in duck selection and improvement.

• Korean Journal of Cognitive Science
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• v.16 no.3
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• pp.189-197
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• 2005

In this study, changes in performance of 2-back task, blood oxygen saturation and heart rate due to $40\%$ concentration oxygen supply were observed. Five male $(25.8\pm1.3)$ and five female $(23.0\pm1.0)$ college students were nked to perform 2-bark task during two types of oxygen (concentration $21\%,\;40\%$) administration. The experimental sequence consisted of Rest1(1 min.), 0-back Task (1 min.), 2-bark Task (2 min.), and Rest2 (4 min.) and the physiological signals such as blood oxygen saturation and heart rate were measured throughout the stages. The experimental result showed that the performance increased significantly at $40\%'s$ concentration of oxygen rather than $21\%'s$, which shows oxygen supply has positive influence on cognitive performance. When $40\%$ concentration oxygen is supplied, the oxygen saturation in the blood increased and heart rate was decreased significantly comparing to $21\%$. It is Suggested that $40\%$ oxygen can stimulate brain activation bY increasing actual blood oxygen concentration in the process of cognitive performance, and hyperoxia makes heart rate decrease.

• Korean Journal of Microbiology
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• v.37 no.4
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• pp.265-272
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• 2001

The diversity of acid-tolerant epiphytic bacterial communities on deciduous oak tree (Quercus dentate Thunb.) leaves was examined both in the natural forest area with a clean air and in the industrial estate to assess effects of acidic depositions to the phyllosphere using 16S rDNA sequence data. A total of 444 acid-tolerant epiphytic bacterial clones were obtained, resulting in 17 phylotypes by performing a analysis of restriction fragment length polymorphism (RFLP) for PCR-amplified 16S rDNA products. A very low diversity of dominating acid tolerant bacterial communities in both areas was found, just 2 subphyla groups, $\gamma$-Proteobacteria and low-G+C gram-positive bacteria. As tree leaves grow older, diversities of acid-tolerant bacteria on them significantly increased. The community structure of acid-tolerant epiphytic bacteria consisted of Pseudomonas and Enterobacteriaceae groups in the $\gamma$-Proteobacteria subphylum, and Streptococcaceae and Staphylococcus groups in the low-G+C gram-positive bacteria subphylum. The direct influence of acidic depositions on bacterial phylogenetic composition could not be detected especially when higher taxonomic levels such as subphylum, but at narrower or finer levels it could be observed by a detection of Xanthomonadales group belonged to the $\gamma$-Proteobacteria only in the industrial area and of Acetobacteraceae group belonged to the $\alpha$-Proteobacteria. There remains that these specific acid-tolerant epiphytic bacterial groups could be used as indicators for assessing effects of acidic depositions on the phyllosphere.

• Journal of Korean Society of Environmental Engineers
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• v.37 no.5
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• pp.269-276
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• 2015

This study investigated the influence of characteristics of natural organic matter (NOM) on the formation of disinfection by-products (DBPs), and proposed the control strategies of DBPs formation in a drinking water treatment plant using lake water in Gyeongsangbuk-do. The fluorescence excitation-emission matrix analysis results revealed that the origins of NOM in raw waters to the plant were a mixture of terrestrial and microbial sources. Molecular size distributions and removals of NOM fractions were evaluated with a liquid chromatography-organic carbon detector (LC-OCD) analysis. Humic substances and low molecular weight organics were dominant fractions of NOM in the raw water. High molecular weight organics were relatively easier to remove through coagulation/precipitation than low molecular weight organics. The concentrations of DBPs formed by pre-chlorination increased through the treatment processes in regular sequence due to longer reaction time. Chloroform (74%) accounts for the largest part of trihalomethanes, followed by bromodichloromethane (22%) and dibromochloromethane (4%). Dichloroacetic acid (50%) and trichloroacetic acid (48%) were dominant species of haloacetic acids, and brominated species such as dibromoacetic acid (2%) were minimal or none. Dichloroacetonitrile (60%) accounts for the largest part of haloacetonitriles, followed by bromochloroacetonitrile (30%) and dibromoacetonitrile (10%). The formation of DBPs were reduced by 16~44% as dosages of pre-chlorine decreased. Dosages of pre-chlorine was more contributing to DBPs formation than variations of dissolved organic contents or water temperature.

• The Research Journal of the Costume Culture
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• v.7 no.4
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• pp.99-110
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• 1999

In order to help the marketers of the men\`s casual wear brands establish the marketing strategies to their target consumers, it is the purpose of this study to investigate on the variables affecting the casual wear purchase behavior of men in twenties, thirties and forties, and to clarify the differences of casual wear purchase behavior according to their age, The subjects were 429 men in their twenties, thirties and forties living in Seoul and data were analyzed by frequency, percentage, mean and standard deviation, x², ANOVA and Duncan\`s test. The results were as follows : (1) Significant differences were found among men in twenties, thirties and forties according to the self-image. Men in forties favored the conservative and not-noticeable image of casual wear, however, men in twenties and thirties favored those of the active, sexy, and distinctive image. (2) Significant differences were found among men in twenties, thirties and forties according to the importance of the store attributes such as convenience of transportation and parking place, clothing in vogue, and various merchandise. Men in thirties and forties put more importance on convenience of transportation and parking place. Men in forties put more importance on various merchandise than men in twenties and thirties. (3) Significant differences were found among men in twenties, thirties and forties according to general purchase behavior of casual wear. * Differences of the use of information according to age Majority of the men consulted the T.V., radio and people in their boundaries * Differences of the clothing purchase frequency according to age Men in twenties buy more clothing than other age groups. Men in twenties buy the clothing every one month and every three months and men in thirties and forties buy the clothing every three months and every six months. * Differences of the shopping day according to age Majority of the men buy the clothing on Saturday and Sunday. However men in twenties buy the clothing more on weekdays than other age groups. * Differences of the shopping place according There were not significant differences among three different age groups and majority of the men found out to utilize the department store. * Differences of the influence of the partners according to age Men in twenties found out to rely on their own decisions but men in thirties and forties found out to depend on their wives(loves). * Differences of the selection standards of casual wear according to age There were not significant differences according to age and adult males found out to select the casual wear by design, quality price in sequence.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.28 no.6A
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• pp.341-350
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• 2003

In this paper, we evaluate the performance of a moving average (MA) channel estimation filter when space-time block coding transmit diversity (STBC-TD) is applied to the wideband direct sequence code division multiple access (WCDMA) forward link. And we present the infinite impulse response (IIR) filter scheme that can reduce the required memory buffer and the channel estimation delay time. This paper also compares the performance between MA filter scheme and IIR filter scheme in various Rayleigh fading channel environments through the bit error rate (BER) and the frame error rate (FER). Extensive computer simulation results show that transmission with STBC-TD provides a significant gain in performance over no transmit diversity technique, particularly at pedestrian speeds. If STBC-TD technique is employed in the channel estimator based on MA filter, it provides considerable performance gains against Rayleigh fading and reduces the optimum filter tap number. Consequently, the channel estimation delay time and the complexity of the receiver are reduced. In addition, the channel estimator based on IIR filter has the advantages such as little memory requirement and no delay time compared to the MA scheme. However, IIR filter coefficients is very sensitive to the mobile speed change and it exerts a serious influence upon the performance. For that reason, it is important to set uP the optimum IIR filter coefficients.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.2
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• pp.698-705
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• 2014

R&D investment has rised in recent years. Korea's R&D budget is 43.8 trillion won which is 3.74% adjusted gross domestic product in 2010. Technological advances and technical inovation will bring productivity growth to Firm and Firm's productivity growth will increase GDP in sequence. Therefore the importance of study on the Firm's R&D industry is getting growing. In this study we attempt to analyse the economic impact of the Firm's R&D industry through several years using an inter-industry analysis. Specifically, this study analyze production-inducing effect, value added inducing effect, and employ-inducing effect based on demand-driven model. The analysed results of year from 1995 to 2009, the Firm's R&D investment increases production-inducing effect, value added inducing effect, and employ-inducing effect with the course of time. This means that influence of the Firm's R&D industry has increased.

• Journal of the Korean Society of School Health
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• v.13 no.1
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• pp.63-84
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• 2000

Primary school is regarded as an important period when many health-related behaviors and life-styles begin to be formed. Acquiring them through school heath education has a strong influence on the health promotion of not only the family but also the community. Primary school health education in Korea has a systematic flaw in that health-related subjects are divided and taught under various subjects in primary school. In order to develop a proper school health curriculum, it is essential to assess what is currently being taught. In this study the current health education of the 6th grade primary curriculum was investigated to improve school health education. The purpose of this study is to identify the health education contents and time in textbooks of the 6th grade primary school curriculum. In this study, the textbooks & teacher's teaching manuals of the 6th grade curriculum were analyzed with a health instruction framework for Korean schools developed by the Korean Nurse Association & Korean School Health Education Association in 1993 and health care framework for health education curriculum presented by Kim in 1991. The results are as follows ; 1) Health education hours of the curriculum are 206 hours, about 34.3 hours a year. 2) The contents of health education were divided into nine subjects at primary schools. Organizing principles of learning experience(eg, integrity, sequence and continuity) were not considered sufficiently. The physical education & natural science subjects include a lot of health education contents. 3) The major content areas are community & environmental health areas and daily healthy life areas. 4) The major areas at each grade level are daily healthy concerns and safety & first-aid 5) The remarkable contrast to the 5th primary school curriculum are that environmental health is offered to the first grade step by step, and that drug use & abuse and mental health education are included in the 6th primary school curriculum. 6) The main contents of health education in 1st, 2nd. and 3rd grade curricula consist of treatment & recovery health functions. Those of the 4th grade curriculum consist of treatment & recovery health functions, and daily healthy life functions. Those of the 5th grade consist of growth & development functions. Those of the 6th grade consist of treatment & recovery health, growth & development functions. Most health care functions belong to physical health care. The results above suggest that we put together the divided contents of health education and manage them on the basis of systematic integration.