• Microbiology and Biotechnology Letters
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• v.44 no.4
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• pp.504-511
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• 2016

Lactulose, a synthetic disaccharide, has received increasing interest because of its role as a prebiotic that can increase the proliferation of Bifidobacterium and Lactobacillus spp. and enhance the absorption of calcium and magnesium. While the industrial production of lactulose is still mainly achieved by the chemical isomerization of lactose in alkaline media, this process has drawbacks including the need to remove catalysts and by-products, as well as high energy requirements. Recently, the use of cellobiose 2-epimerase (CE) has been considered an interesting alternative for industrial lactulose production. In this study, to develop a process for enzymatic lactulose production using CE, we screened improved mutant enzymes ($CS-H^RC^E$) from a library generated by an error-prone PCR technique. The thermostability of one mutant was enhanced, conferring stability up to $75^{\circ}C$, and its lactulose conversion yield was increased by 1.3-fold compared with that of wild-type CE. Using a recombinant Escherichia coli strain harboring a CS35 $H^RC^E$-expressing plasmid, we prepared cell beads immobilized on a Ca-alginate substrate and optimized their reaction conditions. In a batch reaction with 200 g/l lactose solution and the immobilized cell beads, lactose was converted into lactulose with a conversion yield of 43% in 2 h. In a repeated 38-plex batch reaction, the immobilized cell beads were relatively stable, and 80% of the original enzyme activity was retained after 4 cycles. In conclusion, we developed a reasonable method for lactulose production by immobilizing cells expressing thermostable CE. Further development is required to apply this approach at an industrial scale.

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2001.11a
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• pp.7-7
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• 2001

The increasing interest in light weight materials coupled to the need for cost -effective processing have combined to create a significant opportunity for aluminum P/M. particularly in the automotive industry in order to reduce fuel emissions and improve fuel economy at affordable prices. Additional potential markets for Al PIM parts include hand tools. Where moving parts against gravity represents a challenge; and office machinery, where reciprocating forces are important. Aluminum PIM adds light weight, high compressibility. low sintering temperatures. easy machinability and good corrosion resistance to all advantages of conventional iron bm;ed P/rv1. Current commercial alloys are pre-mixed of either the AI-Si-Mg or AL-Cu-Mg-Si type and contain 1.5% ethylene bis-stearamide as an internal lubricant. The powder is compacted in closed dies at pressure of 200-500Mpa and sintered in nitrogen at temperatures between $580~630^{\circ}C$ in continuous muffle furnace. For some applications no further processing is required. although most applications require one or more secondary operations such as sizing and finishing. These sccondary operations improve the dimension. properties or appearance of the finished part. Aluminum is often considered difficult to sinter because of the presence of a stable surface oxide film. Removal of the oxide in iron and copper based is usually achieved through the use of reducing atmospheres. such as hydrogen or dissociated ammonia. In aluminum. this occurs in the solid st,lte through the partial reduction of the aluminum by magncsium to form spinel. This exposcs the underlying metal and facilitates sintering. It has recently been shown that < 0.2% Mg is all that is required. It is noteworthy that most aluminum pre-mixes contain at least 0.5% Mg. The sintering of aluminum alloys can be further enhanced by selective microalloying. Just 100ppm pf tin chnnges the liquid phase sintering kinetics of the 2xxx alloys to produce a tensile strength of 375Mpa. an increilse of nearly 20% over the unmodified alloy. The ductility is unnffected. A similar but different effect occurs by the addition of 100 ppm of Pb to 7xxx alloys. The lend changes the wetting characteristics of the sintering liquid which serves to increase the tensile strength to 440 Mpa. a 40% increase over unmodified aIloys. Current research is predominantly aimed at the development of metal matrix composites. which have a high specific modulus. good wear resistance and a tailorable coefficient of thermal expnnsion. By controlling particle clustering and by engineering the ceramic/matrix interface in order to enhance sintering. very attractive properties can be achicved in the ns-sintered state. I\t an ils-sintered density ilpproaching 99%. these new experimental alloys hnve a modulus of 130 Gpa and an ultimate tensile strength of 212 Mpa in the T4 temper. In contest. unreinforcecl aluminum has a modulus of just 70 Gpa.

• Korean Journal of Animal Reproduction
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• v.23 no.3
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• pp.213-220
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• 1999

The litter size has been the primary interest of economic traits in pig reproduction. It has been recently shown that insulin-like growth factor-Ⅰ(IGF-Ⅰ) plays roles in establishing pregnancy and in supporting fetal growth and development. But, the effect of serum IGF-Ⅰ on litter size has not been studied. Therefore, this study was conducted to relate serum IGF-Ⅰ concentration with porcine litter size and to investigate the possible connection with estrogen receptor(ER) as a candidate gene for the litter size. Sera during day 45 to 105 of pregnancy were collected from two groups showing high and low litter size and serum IGF-Ⅰ concentration was measured by radioimmunoassay (RIA). IGF-Ⅰ levels in both groups decreased gradually as pregnancy stage proceeded but were not significantly different. Secondly, DNA was extracted from blood and PCR-RFLP was utilized to analyze ER genotypes of pigs in each group, which produced three polymorphic patterns. Based on the ER genotypes analyzed, low litter size group showed higher IGF-Ⅰ concentration than high litter size group. Taken together, the results indicate that the serum IGF system was correlated with steroid system but not with the litter size in pigs. Thus, this study implies that porcine litter size could be determined locally at the ovary level.

• Journal of Animal Science and Technology
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• v.57 no.1
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• pp.1.1-1.11
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• 2015

Background: Due to increased interest in animal welfare, there is now a need for a comprehensive assessment protocol to be used in intensive pig farming systems. There are two current welfare assessment protocols for pigs: Welfare Quality$^{(R)}$ Assessment Protocols (applicable in the Europe Union), that mostly focuses on animal-based measures, and the Swine Welfare Assurance Program (applicable in the United States), that mostly focuses on management- and environment-based measures. In certain cases, however, animal-based measures might not be adequate for properly assessing pig welfare status. Similarly, welfare assessment that relies only on environment- and management-based measures might not represent the actual welfare status of pigs. Therefore, the objective of this paper was to develop a new welfare protocol by integrating animal-, environment-, and management-based measures. The background for selection of certain welfare criteria and modification of the scoring systems from existing welfare assessment protocols are described. Methods: The developed pig welfare assessment protocol consists of 17 criteria that are related to four main principles of welfare (good feeding, good housing, good health, and appropriate behavior). Good feeding, good housing, and good health were assessed using a 3-point scale: 0 (good welfare), 1 (moderate welfare), and 2 (poor welfare). In certain cases, only a 2-point scale was used: 0 (certain condition is present) or 2 (certain condition is absent). Appropriate behavior was assessed by scan sampling of positive and negative social behaviors based on qualitative behavior assessment and human-animal relationship tests. Results: Modification of the body condition score into a 3-point scale revealed pigs with a moderate body condition (score 1). Moreover, additional criteria such as feed quality confirmed that farms had moderate (score 1) or poor feed quality (score 2), especially those farms located in a high relative humidity region. Conclusions: The developed protocol can be utilized to assess welfare status in an intensive pig farming system. Although further improvements are still needed, this study is a first step in developing a pig welfare assessment protocol that combines animal-, environment-, and management-based measures.

• Journal of the Korean Society for information Management
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• v.35 no.3
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• pp.189-214
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• 2018

The purpose of this study is to identify the status and also to develop improvement plans for the children and youth services of the public libraries. To determine the information service status and the librarians' perceptions on the levels of services they provided, the 2016 Korean National Library Statistics System data and the survey results from the children and youth program librarians in the 108 public libraries were analyzed. The analysis revealed the problems such as lack of human resources and budget, shortage of space, and an inflexible program curriculum, which affect the program as a whole negatively. Five suggestions were made to remedy the problems. They are: 1) development of the new programs, which can interest the children and youth and motivate the sense of association among the program participants; 2) increase the number of the programs including the schools and other related organizations nearby region; 3) incorporating the new program formats to enhance the participation; 4) starting the new services explicitly targeted for the information-poor group of people; and 5) soliciting policy-level support for the libraries. In summary, this study made a few suggestions for the libraries ranging from planning the programs to requesting assistance from the national as well as the regional governments.

• Journal of Satellite, Information and Communications
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• v.12 no.4
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• pp.78-86
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• 2017

Japan has a lot of interest about weapons systems development of surrounding national and has invested heavily in securing intelligence assets to get information about them, because of conflict issues between Japan and Russia with four northern islands, China with Senkaku Islands and entry policy into the Pacific. Japan has used a large budget to detect and intercept ballistic missile for reasons of the launch of the Taepodong missile in 1998. After took over SIGINT equipments which U.S. force had operated in 1950s~1960s, Japan made a technological analysis and advanced IT technology to produce superior equipments. Japan's SDF has installed them in 19 locations across Japan. In addition, Japan's JASDF has installed advanced early warning RADAR to detect aircraft and high speed ballistic missile entering JADIZ with S-band in 28 locations across Japan. It is possible to detect missile launch preparations, engine tests, and launch moments at any time for operation of 6 satellites high resolution reconnaissance system and 6 aegis ships. In close cooperation with the US, Japan is accessible to the SBIRS networks which detects the launch of a ballistic missile in neighboring countries. In the future, Because the United States wants Japan to act as part of the United States in East, south Asia, it is believed that the exchange of intelligence on the surrounding countries between two countries will be enhanced.

• The Journal of the Korea Contents Association
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• v.20 no.8
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• pp.315-326
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• 2020

Corporate efforts to build strong brands have made consumers interested in brand love. In the field of brand love, however, there is a lack of systematic research on the multidimensionality of the concept of brand love and on the scale development to measure it. Thus, based on the methodological research design of Churchill(1979) and DeVellis(1991), this study explored properties of brand love and classified them into two levels - 'emotion' and 'relationship' - and generated corresponding measurement items. To do this, the research was conducted in a total of eight stages, including preliminary studies such as literature review, open surveys, and in-depth interviews, as well as the main study process in which the factors were analyzed step by step. As a result, the level of emotion appeared to have five subcomponents (self-esteem, warmth, interest, responsibility, pleasure) with 19 items, and the level of relationship - three subcomponents (unchanging, sharing/supporting, understanding) with 11 items, adding up to a total of 30 measurement items for brand love with reliability, convergent and discriminant validity, and nomological validity. Additionally, we intended to expand the scope of research related to brand love by presenting the result model of organic interaction between the concepts that constitute brand love and proposing '4 categories of brand love strength' based on it.

• School Mathematics
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• v.13 no.2
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• pp.307-321
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• 2011

Recognizing the importance of affective factors in mathematical learning and achievement, international comparative assessment as PISA and TIMSS survey affective achievement as well as scholastic achievement. On the affective survey those items of PISA are categorized by 5 factors ; interest of mathematics, instrumental motivation, Mathematics self-efficacy, mathematics anxiety, mathematics self-concept) and those of TIMSS are categorized by 3 factors; Positive affect toward mathematics (PATM), Students' Self-Confidence in Learning Mathematics(SCM), and Students' Valuing Mathematics(SVM). In this study we carried out Exploratory Factor Analysis, Confirmatory Factor Analysis and Measurement Equivalence/Invariance to find whether the constructs are well defined and divided. As a result of our analysis, some factors were overlapped in PISA whereas the items of TIMSS were categorized as intended in TIMSS study. Based on these results, it is confirmed that the questionnaire items need to be developed to understand our students affective characteristics. Also, how questionnaire of large-scaled international assessment can give implication to the development of the questionnaire of Korean specific.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.2
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• pp.19-24
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• 2020

The interest in renewable energy is increasing due to the depletion of fossil fuels. In particular, active research on wave power, which is highly predictable and abundant, is being conducted. The coaxial accelerator-type wave power generator used in this study was designed to improve the power generation efficiency by converting bidirectional linear motion into a rotational force. In an offshore engineering basin, waves were generated, and case tests were performed according to the wave period and wave height. The experimental results were verified by the theoretical method related to the frequency response, and the overall trend was confirmed to be consistent. These results are expected to be useful in estimating the power of wave generators and designing parameters to improve the efficiency of wave energy in the design stage before manufacturing. In addition, the manufacturer can predict the wave energy efficiency of wave generators, which can reduce the development time and cost by preventing trial and error processes.

• Asian Oncology Nursing
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• v.4 no.2
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• pp.124-134
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• 2004

The major results of this study were as follows : 1. The percentage of nurses who know the complementary and alternative therapies was 50.1% Most of them(70.6%) acknowledged the therapies from newspapers, television and magazines. 2. The complementary and alternative therapy was perceived as effective by 64.9% of the nurses and as trusted by 60.2% of them The effective methods of the therapy are acupuncture herb medicine and massage. 3. Most of the nurses 93.4% experienced getting inquiries from patients or their guardians whether to use the therapies. 4. The complementary and alternative therapies was experienced by 38.9% of nurses and 7.1% of them use the therapies frequently 92.9% of patients and families were satisfied with the result 'Massage Therapy' was used the most with no side-effects and thus higher need of education for nurses. 5. They wanted to be trained for massage therapy finger-pressure, music therapy, acupuncture, aroma therapy in order. 6. Reliance on the complementary and alternative therapies, 75.2% of nurses completed the course trusted the therapies and the result of others uncompleted was similar as 52.2% Moreover both 79.5% of nurses completed it and 61.6% of the others said that the complementary and alternative therapy's nursing interventions is possible to develop. 7. It shows high relation to recognition having possibilities for applying and developing as the nursing intervention. if the confidence is as high as about the complementary and alternative therapies. Based of the results of this study as above this study proposes as follows. First, The nurses should understand mentality of the patients so that the nurses have to put in operation appropriate nursing intervention as accurate knowledge of the alternation therapies using to cancer patients for having on damages to patients from their rash using way. Furthermore, it is necessary to supply the special place and the professional nurses taking complete charge at them. Next politic interest and support from government are required to develop and practice systematic and resonable education programs for the complementary and alternative therapies. Moreover, it is necessary for nurses to be educated about the therapies continually. Finally, it is compulsory that the research and development for complementary and alternative therapies is needed. In addition, it has to be made standard and legal equipment for safety efficacy and theory about the therapies.