• Current Research on Agriculture and Life Sciences
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• v.1
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• pp.179-188
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• 1983

This study was conducted to find out the most fabourable breeding structure for the maximum genetic gain of live weight, the most important economic traits of Korean native cattle, in order to achieve the improvement goals for meat productivity of the native cattle early and effectively. For estimating genetic gain and population mean changes, the following factors were investigated under the assumation that 675,000 heads of over-two-year old cows were maintained each generation and 15% of the cows were culled every year: 1. The proportion of cow population inseminated by A I bulls; 30, 40, 50, 60, 70% 2. The number of semen doses produced from each A I bull per year; 5,000, 7,000, 10,000, 15,000, 20,000 doses. 3. The average body weight of A I bulls; 480, 520, 600, 640, 680, 720kg/18 months of age. The estimated results are summarized as follows: 1. The genetic gain of live weight is affected greately by the levels of A I bulls' body weight and the genetic gain was estimated 28.66~36.31kg per generation. 2. The proportion of genetic gain from sire selection were estimated 80~90%. 3. When the average body weight of A I bulls increase 40kg per generation and more than 50% of cow population is inseminated by A I bulls, then the phenotypic mean value of live weight of bulls at the age of 18 months and heifers at the age of 2 years are expected to be reached 600kg and 520kg in the A I population; 560kg and 480kg in the whole population, respectively, after 5th generation.

• Journal of Intelligence and Information Systems
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• v.28 no.2
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• pp.207-235
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• 2022

In a knowledge-based society where knowledge and information industries are the main pillars of the economy, knowledge sharing and diffusion and its systematic management are recognized as essential strategies for improving national competitiveness and sustainable social development. In the field of Information Systems (IS) research, where the convergence of information technology and management takes place in various ways, the evolution of knowledge occurs only when researchers cooperate in turning old knowledge into new knowledge from the perspective of the scientific knowledge network. In particular, it is possible to derive new insights by identifying topics of interest in the relevant research field, applied methodologies, and research trends through network-based interdisciplinary graftings such as citations, co-authorships, and keywords. In previous studies, various attempts have been made to understand the structure of the knowledge system and the research trends of the relevant community by revealing the relationship between research topics, methodologies, and co-authors. However, most studies have compared two or more journals and been limited to a certain period; hence, there is a lack of research that looked at research trends covering the entire history of IS research. Therefore, this study was conducted in the following order for all the papers (from its first issue in 1977 to the first quarter of 2022) published in the MIS Quarterly (MISQ) Journal, which plays a leading role in revealing knowledge in the IS research field: (1) After extracting keywords, (2) classifying the extracted keywords into research topics, methodologies, and theories, and (3) using topic modeling and keyword network analysis in order to identify the changes from the beginning to the present of the IS research in a chronological manner. Through this study, it is expected that by examining the changes in IS research published in MISQ, the developing patterns of IS research can be revealed, and a new research direction can be presented to IS researchers, nurturing the sustainability of future research.

• Journal of the Korean Geotechnical Society
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• v.35 no.10
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• pp.47-66
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• 2019

A parametric numerical analysis according to diameter, length, and N values of soil was conducted for the PHC pile socketed into weathered rock through sandy soil layers. In the numerical analysis, the Mohr-Coulomb model was applied to PHC pile and soils, and the contacted phases among the pile-soil-cement paste were modeled as interfaces with a virtual thickness. The parametric numerical analyses for 10 kinds of pile diameters were executed to obtain the load-settlement relationship and the axial load distribution according to N-values. The load-settlement curves were obtained for each load such as total load, total skin friction, skin friction of the sandy soil layer, skin friction of the weathered rock layer and end bearing resistance of the weathered rock. As a result of analysis of various load levels from the load-settlement curves, the settlements corresponding to the inflection point of each curve were appeared as about 5~7% of each pile diameter and were estimated conservatively as 5% of each pile diameter. The load at the inflection point was defined as the mobilized bearing capacity ($Q_m$) and it was used in analyses of pile bearing capacity. And SRF was appeared above average 70%, irrespective of diameter, embedment length of pile and N value of sandy soil layer. Also, skin frictional resistance of sandy soil layers was evaluated above average 80% of total skin frictional resistance. These results can be used in calculating the bearing capacity of prebored PHC pile, and also be utilized in developing the bearing capacity prediction method and chart for the prebored PHC pile socketed into weathered rock through sandy soil layers.

• Applied Microscopy
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• v.39 no.2
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• pp.133-139
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• 2009

A officinal mushroom, Phellinus linteus (PL) has been known to exhibit potent biological activities including antioxidative and anticancer effect. PL is consumed as a type of powder or extract for the purpose of health promotion and disease treatment. Recently superfine PL products was commercialized according to the development of pulverizing technology such as nanomill, so the evaluation of food safety is suggested. This study was conducted to evaluate the food safety of superfine PL (SPL) through hematological, biochemical and histological examination in mice as compared with fine PL (FPL). In the particle size distribution in volume after nanomill processing, the mean diameter of SPL and FPL particles was 11.78 ${\mu}m$ and 216.1 ${\mu}m$, and d (0.5), the particle diameter measured at 50% of distribution was 5.5 ${\mu}m$ and 147.9 ${\mu}m$, respectively. As the result of body weight, food intake and the weight of organs, SPL group didn't show any statistical difference compared with FPL group and normal group (N). Hematological and biochemical values were also involved in the normal range, although ALT (N vs. FPL, P<0.001) and BUN (N vs. FPL, P<0.01; N vs. SPL, P<0.01) showed significance compared with N group but there are no significance between FPL and SPL group. In the result of histological examination with liver, kidney, spleen, and small and large intestine, abnormal findings such as inflammatory reaction and histological changes were not observed. Our results suggest that the oral intake of SPL diet is not harmful to the animal in the hematological, biochemical and histological aspects although particle size was reduced to the level of superfine. However, further study will be necessary to confirm the histological safety in relation to the gastrointestinal contact of superfine particles in the case of large amount and long-term intake.

• Tuberculosis and Respiratory Diseases
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• v.50 no.1
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• pp.29-41
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• 2001

Background : The appearance of multiple-drug-resistant Mycobacterium tuberculosis strains has been seriously compromising successful control of tuberculosis. Rifampin-resistance, caused by mutations in the rpoB gene, can be indicative of multiple-drug-resistance, and its detection is of great importance. The present study aimed to develop an oligonucleotide chip for accurate and convenient screening of drug-resistance. Methods : In order to detect point mutations in the rpoB gene, an oligonucleotide chip was prepared by immobilizing specific probe DNA to a microscopic slide glass by a chemical reaction. The probe DNA that was selected from the 81 bp core region of the rpoB gene was designed to have mutation sites at the center. A total of 17 mutant probes related to rifampin-resistance including 8 rifabutin-sensitive mutant probes were used in this study. For accurate determination, wild type probes were prepared for each mutation position with an equal length, which enabled a direct comparison of the hybridization intensities between the mutant and wild type. Results : Mycobacterial genomic DNA from clinical samples was tested with the oligonucleotide chip and the results were compared with those of the drug-susceptibility test in addition to sequencing and INNO-LiPA Rif. TB kit test in some cases. Out of 15 samples, the oligonucleotide chip results of 13 samples showed good agreement with the rifabutin-sensitivity results. The two samples with conflicting result also showed a discrepancy between the other tests, suggesting such possibilities as existence of mixed strains and difference in drug-sensitivity. Further verification of these samples in addition to more case studies are required before the final evaluation of the oligonucleotide chip can be made. Conlcusion : An oligonucleotide chip was developed for the detection of rpoB gene mutations related to drugsusceptibility. The results to date show the potential for using the oligonucleotide chip for accurate and convenient screening of drug-resistance to provide useful information in antituberculosis drug therapy.

• Journal of Korea Water Resources Association
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• v.55 no.8
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• pp.623-634
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• 2022

Due to river maintenance projects such as the creation of hydrophilic areas around rivers and the Four Rivers Project, the flow characteristics of rivers are continuously changing, and the risk of water quality accidents due to the inflow of various pollutants is increasing. In the event of a water quality accident, it is necessary to minimize the effect on the downstream side by predicting the concentration and arrival time of pollutants in consideration of the flow characteristics of the river. In order to track the behavior of these pollutants, it is necessary to calculate the diffusion coefficient and dispersion coefficient for each section of the river. Among them, the dispersion coefficient is used to analyze the diffusion range of soluble pollutants. Existing experimental research cases for tracking the behavior of pollutants require a lot of manpower and cost, and it is difficult to obtain spatially high-resolution data due to limited equipment operation. Recently, research on tracking contaminants using RGB drones has been conducted, but RGB images also have a limitation in that spectral information is limitedly collected. In this study, to supplement the limitations of existing studies, a hyperspectral sensor was mounted on a remote sensing platform using a drone to collect temporally and spatially higher-resolution data than conventional contact measurement. Using the collected spatio-temporal hyperspectral images, the tracer concentration was calculated and the transverse dispersion coefficient was derived. It is expected that by overcoming the limitations of the drone platform through future research and upgrading the dispersion coefficient calculation technology, it will be possible to detect various pollutants leaking into the water system, and to detect changes in various water quality items and river factors.

• Development and Reproduction
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• v.11 no.2
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• pp.111-119
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• 2007

Differentiation of cells can be induced through modulation of endogenous regulators using exogenous factors. Useful transfection systems to transport a specific exogenous regulator into cell have been tried but still there are many obstacles to overcome. In this study, we examined the transfection efficiency of cell permeable peptides (CPPs) in mouse embryonic stem cell under the various conditions. To identify the CPP-mediated translocation of a protein, we employed recombinant CPP-enhanced green fluorescent protein (EGFP). Viability of R1 cells was different between experimental groups depending on the kind of CPP and the concentration of CPP-EGFP. Translocation of CPP-EGFPs into the R1 cells was not detected until 30 min after CPP-EGFPs treatment in all groups. After 1 hr, translocation of pEP-1-EGFP-N was detected, but it could not be detected in the other group. Transfection of pEP-1EGFP-N was independent on its concentration. The time course did not show saturation even after 24 hr in pEP-1-EGFP-N. These results showed that the permeability depended on the kind of CPP and the location of His-tag in the case of examined CPPs, and did not need biological energy. On summary, the efficiency of transfection of CPP-EGFP depends on the CPP sequences but the culture time is not a key factor in transfection for the mouse embryonic stem cell. For the future studies to improve the efficiency of translocation of protein into embryonic stem cells, it is needed to develop modified CPP or mediator. The studies would be very useful to induce the differentiation of embryonic stem cells.

• The Korean Journal of Archival Studies
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• no.23
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• pp.87-139
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• 2010

Unlike in the past, a new paradigm has been presented which the use of records is much more important than the preservation of those in the present. It will be necessary for users to signalizes the value of records and to make themselves easily accessible to records in order that records should be more effectively used. To meet the needs of the times, it is the very 'Contents' that starts to attract public attention. National Archives in England produces and provides contents utilizing multi-media by using digital technology on various sorts of archives which England has. In addition to England, Asian Historical Records center in Japan in Japan makes Archival Contents Service reflecting users' needs and continues to update the latest contents. What is more, National Archives of Korea has recently promoted the introduction of digital archive by the change of archival paradigm in records management, and it is giving an impetus to the development of contents in the digital archive. In fact, it is crucial to keep as many contents as possible and to give service to public, but it will not be possible to get positive response from public and to offer much higher level of archival information service until the quality of contents is highly improved. Accordingly, this manuscript analyzed the feature and type of contents which National Archives of Korea provides with cases of both TNA in England and Asian Historical Records center in Japan, each of which has different characteristics. Also, it dealt with several methods of the usage of contents in those organizations. Furthermore, this study explained what kind of contents and feedback are given to users. Moreover, it divided the components of contents of three institutions as mentioned into three by information provided and evaluated the quality of contents by establishing the details of contents. In addition, there were implications for archives with regard to reference for building contents.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.107-107
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• 2017

Sweet corns are enjoyed worldwide as processed products and fresh ears. Types of sweet corn are based on the gene(s) involved. The oldest sweet corn type has a gene called "sugary (su)". Sugary-based sweet corn was typically named "sweet corn". With its relatively short shelf life and the discovery of a complementary gene, "sugary enhanced (se)", the sweet corn (su only) was rapidly replaced with another type of sweet corns, sugary enhanced sweet corn, which has recessive homozygous su/su, se/se genotype. With the incorporation of se/se genotype into existing su/su genotype, sugary enhanced sweet corn has better shelf life and increased sweetness while maintaining its creamy texture due to high level of water soluble polysaccharide, phytoglycogen. Super sweet corn as the name implies has higher level of sweetness and better shelf life than sugary enhanced sweet corn due to "shrunken2 (sh2)" gene although there's no creamy texture of su-based sweet corns. Distinction between sh2/sh2 and su/su genotypes in seeds is phenotypically possible. The Involvement of se/se genotype under su/su genotype, however, is visually impossible. The genotype sh2/sh2 is also phenotypically epistatic to su/su genotype when both genotypes are present in an individual, meaning the seed shape for double recessive sh2/sh2 su/su genotype is much the same as sh2/sh2 +/+ genotype. Hence, identifying the double and triple recessive homozygous genotypes from su, se and sh2 genes involves a testcross to single recessive genotype, chemical analysis or DNA-based marker development. For these reasons, sweetcorn breeders were hastened to put them together into one cultivar. This, however, appears to be no longer the case. Sweet corn companies began to sell their sweet corn hybrids with different combinations of abovementioned three genes under a few different trademarks or genetic codes, i.g. Sweet $Breed^{TM}$, Sweet $Gene^{TM}$, Synergistic corn, Augmented Supersweet corn. A total of 49 commercial sweet corn F1 hybrids with B73 as a check were genotyped using DNA-based markers. The genotype of field corn inbred B73 was +/+ +/+ +/+ for su, se and sh2 as expected. All twelve sugary enhanced sweet corn hybrids had the genotype of su/su se/se +/+. Of sixteen synergistic hybrids, thirteen cultivars had su/su se/se sh2/+ genotype while the genotype of two hybrids and the remaining one hybrid was su/su se/+ sh2/+, and su/su +/+ sh2/+, respectively. The synergistic hybrids all were recessive homozygous for su gene and heterozygous for sh2 gene. Among the fifteen augmented supersweet hybrids, only one hybrid was triple recessive homozygous (su/su se/se sh2/sh2). All the other hybrids had su/su se/+ sh2/sh2 for one hybrid, su/su +/+ sh2/sh2 for three hybrids, su/+ se/se sh2/sh2 for three hybrids, su/+ se/+ sh2/sh2 for four hybrids, and su/+ +/+ sh2/sh2 for three hybrids, respectively. What was believed to be a classic super sweet corn hybrids also had various genotypic combination. There were only two hybrids that turned out to be single recessive sh2 homozygous (+/+ +/+ sh2/sh2) while all the other five hybrids could be classified as one of augmented supersweet genotypes. Implication of the results for extension service and sweet corn breeding will be discussed.

• Archives of design research
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• v.19 no.2 s.64
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• pp.241-250
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• 2006

Hangeul as the Korean unique characters were invented according to some character-making principles and based on scholars' exhaustive researches. While most of the characters in the world evolved naturally, Hangeul was invented based on a precise linguistic analysis of the time, and therefore, it is most scientific and reasonable among various characters throughout the world. Nevertheless, Hangeul typeface designs do not seem to inherit the ideology of scientific and reasonable Hangeul correctly. For the square forms have been used intact due to the influences from the Chinese characters which prevailed during the time. If a single set of square characters should be designed, as much as 11,172 fonts should be designed, which suggests that advantages of Mangeul may not well be used fully; Hangeul was invented to visualize every sound with the combinations of 28 vowels and consonants. Problems of such square fonts began to be identified since 1900's when typewriters were introduced first from the West. Since a typewriter is designed with 28 characters laid out on its keyboard by using such combinations, the letters may be easily combined on it. The so-called the flexibility square-format typeface was born as such. Specially, the three-pairs fonts of these can be combined up to 67 letters including vowels and consonants. The three-pairs fonts system can help to solve the problems arising form the conventional square fonts and inherit the original ideology of Hangeul invention. This study aims to review the history of the three-pairs fonts designs facilitated by mechanic encoding of Hangeul and thereupon, suggest some desirable directions for future Hangeul fonts. Since the flexibility square-format typeface is expected to evolve more and more owing to development of the digital technology, they would serve our age of information in terms of both functions and convenience. Just as Hunminjongum tried to be literally independent from the Chinese characters, so the flexibility square-format typeface designs would serve to recover identity of our Hangeul font designs.