• Journal of Food Hygiene and Safety
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• v.15 no.3
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• pp.252-255
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• 2000

This study was conducted to investigate the application of ATP bioluminescence to measure the degree of microbial contamination from raw meat, meat processing and milk processing lines. Samples collected from slaughter house, meat and milk processing plants were tested for estimation of bacterial number by using ATP bioluminescence and conventional method. The former result was transffered to R-mATP value(log RLU/ml), and the latter transffered to CFU(log/ml). Correlation coefficient(r) between aerobic counts(CFU, log/ml) and R-mATP(log RLU/ml) value was 0.93(n=408). R-mATP of aerobic counts from beef, pork, chicken was 0.93(n=220), and that was 0.93(n=187) between meat processing and dairy processing plants. In addition, Correlation coefficient(r) between aerobic counts and R-mATP was 0.87(n=252) under 1$\times$10${^5}$/ml of bacterial count and 0.74(n=152) over 10${^5}$ respectively.

• Journal of the Korean Society for Library and Information Science
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• v.20
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• pp.163-222
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• 1991

This dissertation are studying the conceptual structure of decision making situation in libraries, by analyzing the library function, decision makings of library and then seeking economic and efficient alternative decision making by programming the· decision making situations, and finally, introducing how to apply management information system or decision making support system. For this purpose, in order to analyzing necessary factors for the decision making system, the questionnaire used Lickert method were distributed to 400 librarians of 36 universities in Seoul by means of mail. 193 librarians, $48\%$ of the questionnaire, are returned are studied by using 'SYSTAT' statistical software to figure out the factors of the decision making system. This dissertation was put six hypotheses and tested with the returned questionnaire. The following five result can be asserted. First, to the higher degree of the librarians' participation in the important library decision makings, the quality of formal library services are improved regardless of seniority of the work. Secondly, the t-test results show that all of t-test scores of seniority of the work, educational background, and responsibilities of the work are exceeding significant level and perception of decision making was proved to be different depending on seniority of the work, educational background, and responsibilities of the work in libraries. Thirdly, as the results of factor af factor analysis, the encouragement on participation in the library academic activities, the extent to get useful information about performances of library and the improvements of library works were grouped by similar posibilities of distribution and therfore the academic activities, the collection of information and the improvement of library performances is proved to be interrelational each other. Fourthly, the fifth hypothesis of the close relationship between the decision making situation and types of advisor by it was more or less interrelational, but their relationship was not seen some significancies. Lastly, as the dynamic organization of library management forming a special commitee or a project team with librarian can improve the extent and quality of the librarian's participation in the decision making of library works, and thus library will become to performance more rational and effective library management.

• Journal of The Korean Association of Information Education
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• v.14 no.2
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• pp.157-164
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• 2010

This study proposed the information security integrated learning model-based KASP. By analyzing the teaching materials regarding information security in the regular curriculum, and by investigating preliminary studies, the information security contents were examined in terms of knowledge, attitudes, skills and ways to practice(KASP). And, the KASP-information security learning model integrating knowledge, attitudes, and ways to practice was developed, and the teaching plan and learning material hand-out were accordingly made out. Moreover, the developed model was tested in an experimental group, and common information security learning content centered on ethics in the comparison group in order to compare the results of two groups. As the test result analysis, it was verified that the developed KASP-information security integrated learning model was effective to help the students learn the knowledge, attitudes, skills and ways to practice.

• Journal of Environmental Science International
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• v.20 no.7
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• pp.899-905
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• 2011

In order to develop bacterial cellulose (BC) with antimicrobial activity against pathogenic microorganisms, silver and chitosan were incorporated into BC, respectively. Experiment results showed that antimicrobial activity against pathogenic microorganisms was improved with increasing silver concentration. Chitosan also showed a direct proportion between its concentration and antimicrobial activity. These results suggest that antimicrobial effects of BC using silver and chitosan are well proven to be effective. We also tested the stainability of BC with natural colorant for the application of food industry. Stainability of BC was enhanced with increasing natural colorant concentration. Decolorization of BC stained was observed by dipping it into distilled water with one hour-intervals. As a result, there was no significant difference. Combination of natural colorant-stainability and antibiosis of BC is expected to be useful in making colored antibiotic BC in various industrial application areas, considering its antimicrobial activity, high stainability and low decolorization tendency.

• Clean Technology
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• v.17 no.1
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• pp.31-36
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• 2011

All types of ${\gamma}-Al_2O_3$ such as acidic, neutral and basic forms were chemically modified with (3-mercaptopropyl) trimethoxysilane (3-MPTMS) and oxidized by 30 wt% $H_2O_2$ solution. As a result, sulfonic acid modified ${\gamma}-Al_2O_3$ catalysts were obtained. Their formation was achieved more easily by treating 1M HCl solution. Their catalytic performance was tested by dehydration reaction of D-xylose to furfural. The sulfonic acid modified ${\gamma}-Al_2O_3$ catalysts showed high conversion (>90%) of D-xylose, and the selectivity to furfural was increased with the amount of sulfonic acid anchored on the catalyst.

• Progress in Superconductivity and Cryogenics
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• v.13 no.1
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• pp.1-5
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• 2011

[ $CeO_2$ ]has been widely used for single buffer layer of coated conductor because of superior chemical and structural compatibility with $ReBa_2Cu_3O_{7-{\delta}}$(Re=Y, Nd, Sm, Gd, Dy, Ho, etc.). But, the surface of $CeO_2$ layer showed cracks because of the large difference in thermal expansion coefficient between metal substrate and deposited $CeO_2$ layer, when thickness of $CeO_2$ layer exceeds 100 nm on the biaxially textured Ni-3%W substrate. The deposition rate has been limited to be less than 6 $\AA$/sec in order to get a good epitaxy. In this research, we deposited $CeO_2$ single buffer layers on biaxially textured Ni-3%W substrate with 2-step process such as thin nucleation layer(>10 nm) with low deposition rate(3 $\AA$/sec) and thick homo epitaxial layer(>240 nm) with high deposition rate(30 $\AA$/sec). Effect of deposition temperature on degree of texture development was tested. Thick homo epitaxial $CeO_2$ layer with good texture without crack was obtained at $600^{\circ}C$, which has ${\Delta}{\phi}$ value of $6.2^{\circ}$, ${\Delta}{\omega}$ value of $4.3^{\circ}$ and average surface roughness(Ra) of 7.2 nm within $10{\mu}m{\times}10{\mu}m$ area. This result shows the possibility of preparing advanced Ni substrate with simplified architecture of single $CeO_2$ layer for low cost coated conductor.

• Journal of Microbiology and Biotechnology
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• v.20 no.4
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• pp.683-692
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• 2010

Morphologically, nine different slow-growing protoclones were screened from regenerated protoplasts of heterokaryotic Agaricus bisporus. As such, the present study is the first report on differentiating homo- and heterokaryotic protoclones using random amplified polymorphic DNA (RAPD) and inter-simple sequence repeat (ISSR) markers. Among 80 primers tested, the seven ISSR and seven RAPD primers selected for the analysis generated a total of 94 ISSR and 52 RAPD fragments, respectively. The ISSR fingerprinting also detected more polymorphic loci (38.29%) than the RAPD fingerprinting (34.61%). A principal coordinate analysis (PCA) was employed to evaluate the resolving power of the markers as regards differentiating protoclones. As a result, the mean polymorphism information content (PIC) for each marker system (i.e., 0.787 for RAPD and 0.916 for ISSR) suggested that ISSR is more effective for determining polymorphisms. The dendrograms constructed using RAPD, ISSR, and an integrated RAPD and ISSR marker system were highly correlated with one another as revealed by a high Mantel correlation (r= 0.98). The pairwise similarity index values also ranged from 0.64 to 0.95 (RAPD), 0.67 to 0.98 (ISSR), and 0.67 to 0.98 (RAPD and ISSR), whereas the mean similarity index values of 0.82, 0.81, and 0.84 were obtained for the RAPD, ISSR, and combined data, respectively. As there was a good correspondence between the RAPD and ISSR similarity matrices, ISSR would appear to be an effective alternative to RAPD in the genetic diversity assessment and accurate differentiation of homo- and heterokaryotic protoclones of A. bisporus.

• Journal of Power Electronics
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• v.11 no.2
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• pp.194-201
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• 2011

The air flow supplied to a fuel cell system is one of the most significant factors in determining fuel efficiency. The conventional method of controlling the air flow is to fix the oxygen supply at an estimated constant rate for optimal efficiency. However, the actual optimal point can deviated from the pre-set value due to temperature, load conditions and so on. In this paper, the maximum efficiency point tracking (MEPT) algorithm is proposed for finding the optimal air supply rate in real time to maximize the net-power generation of fuel cell systems. The fixed step MEPT algorithm has slow dynamics, thus it affects the overall efficiency. As a result, the variable step MEPT algorithm is proposed to compensate for this problem instead of a fixed one. The complete small signal model of a PEM Fuel cell system is developed to perform a stability analysis and to present a design guideline. For a design example, a 1kW PEM fuel cell system with a DSP 56F807 (Motorola Inc) was built and tested using the proposed MEPT algorithm. This control algorithm is very effective for a soft current change load like a grid connected system or a hybrid electric vehicle system with a secondary energy source.

• Journal of Conservation Science
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• v.22
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• pp.61-76
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• 2008

We examined characterizations of Paraloid B72 films when it dissolved in four different solvents-acetone, MEK, toluene and xylene. The surface before and after coating were observed by optical microscope and AFM. Thickness and contact angle of films was measured and surface energy was calculated for grasping properties of films. We also tested adhesive strength of films by scratch tester and durability of films by performing yellowing test. The result was that xylene has better coating property than other solvents. Because 10% Paraloid B72 in xylene film is even, non-mottled, thin, stabilized in yellowish and has proper hydrophobic, we confirmed xylene is good solvent for bronze artifact conservation. However, other tests will need for finding appropriate concentration of Paraloid B72.

• Journal of the Korean Geotechnical Society
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• v.18 no.1
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• pp.41-48
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• 2002

Anisotropy of stiffness, from extremely small strains to post-failure strains, of isotropically consolidated air-pluviated sands in plane strain compression was studied by using the newly developed instrumentation fur small strain measurements, Seven types of sand of world-wide origins were tested, which have been extensively used for research purposes. Stress-strain relationships for a wide range of strain from about 0.0001% to the peak were obtained by measuring axial and lateral strains locally free from the effects of bedding and membrane penetration errors at the specimen boundaries. The result showed that the relationship between the principal stress ratio and the principal strain increment ratio was constant, being rarely affected by the over-consolidation ratio and the confining pressure. Although in the small strain the anisotropy hardly affected the relationship between the principal stress ratio and the principal strain increment ratio, the K value around the peak varied according to the $\delta$ value. In general, Rowe\`s stress-dilatancy equation works fairly well from the small strain to the peak.