• Applied Biological Chemistry
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• v.26 no.2
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• pp.110-118
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• 1983

A slimy non-spore-forming bacterium strain SAF-C isolated from bean stem and root was motile with flagella and identified to one of Agrobacterium radiobacter. Studies were made on the conditions necessary for maximal production of this acidic succinoglucan polysaccharide by this strain in shaken culture. Much production was observed with yeast extract,$(NH_4)_2\;HPO_4$, distillers' dried solubles(D.D.S.), as nitrogen source in the medium composed of 4% glucose, 0.5% nitrogen source, 0.3% $CaCO_3$. The yield was greatest with yeast extract and decreased in order with the above nitrogen source from 22.9% to 9.6 percent. A polysaccharide was produced in a yield of about 25% in a medium composed of 3% glucose, 0.4% D.D.S., 0.5% $K_2\;HPO_4$, 0.01% $MgSO_4{\cdot}7H_2O$.

• 전자공학회논문지 IE
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• v.43 no.4
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• pp.105-114
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• 2006

In this paper, 3D input and output systems for a web-based real-time 3D video communication system using IEEE 1394 digital cameras, Intel Xeon Server system and Microsoft Directshow library is proposed. And some conditions for optimizing the operations of the stereo camera, 3D display and signal processing system are analyzed. Input & output systems are carefully selected, which can satisfy the required optimization conditions and the final 3D video communication system is implemented by using three optimized devices. The overall control system is developed with Microsoft Visual C++.Net and Microsoft DirectX 9.1 SDK. Some experimental results show that the observer can feel the natural presence from multi-view(4-view) 3D video of server system in real-time and also can feel the natural presence from 3D video of client system and finally suggest an application possibility of the proposed web-based real-time 3D video communication in real fields.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.43 no.2 s.344
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• pp.24-33
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• 2006

The effective geometry processing IP architecture for mobile SoC that has real time 3D graphics acceleration performance in mobile information system is proposed. Base on the proposed IP architecture, we design the floating point arithmetic unit needed in geometry process and the floating point geometry processor supporting the 3D graphic international standard OpenGL-ES. The geometry processor is implemented by 160k gate area in a Xilinx-Vertex FPGA and we measure the performance of geometry processor using the actual 3D graphic data at 80MHz frequency environment The experiment result shows 1.5M polygons/sec processing performance. The power consumption is measured to 83.6mW at Hynix 0.25um CMOS@50MHz.

• Journal of Society of Preventive Korean Medicine
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• v.6 no.1
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• pp.36-50
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• 2002

Health industry, a knowledge based high value-added industry, is being considered as a strategic area for the 21C and many advanced countries are making every endeavors for the promotion of health industry along with information technology, new materials, and mechatronics. Korean health industry, however, has been excluded from the governmental supports as well as bound by strict regulation so far, and there is a significant gap in technology compared with advanced countries. In 21C, technology is the main factor of national competitiveness and that is why the role of R&D institutes are so important in the high level of competition to cope with the technology protection policies of advanced countries. In this article, with Directory of Korean R&D Institutes published by Korea Industry Technology Association, I reviewed the trends of R&D institute of health industry. Main findings of the research can be summarized as follows. The portion of health industry R&D institute is 3.6% of total R&D institute but the amount of R&D investment is over than 5% This means health industry are knowledge based and R&D intensified industry, meanwhile the variations of same industry R&D institutes of health industry is huge in R&D investments and other activities. Regional distributions of health industry institutes show some kind of different patterns in each industry areas. Medical devices and Medical informatics's preference of metropolitan region are distinguished with other industry areas. Many of the institutes are located in same site of it's company rather than operating separate building for R&D specific uses. It is better for transforming ideas to products and close cooperation of research body with product lines, but it is a handicap for networking and communicating with other research institutions too. It takes 18.4yrs for bearing R&D institute on the average. For a long times 'copy products' or 'me too products' policies were easy way to maintain business entities. But recently, it is recognized that research activities are essential component of sustaining it's own business firms. This means technology itself is leading power of corporation itself in the high level of competition.

• Journal of Food Hygiene and Safety
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• v.30 no.1
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• pp.103-108
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• 2015

Weissella spp. from traditional Korean foods of Kimchi were isolated and characterized against food-borne pathogenic Listeria monocytogens. The isolates were identified as W. cibaria 0D17 and W. confusa 0D23 from Kimchi by the biochemical characteristics and 16S DNA sequencing. The culture solutions of the isolates adjusted to pH 7.0 showed L. monocytogens inhibition. To analyze the quantitative detection of L. monocytogenes, real-time PCR was performed according to the SYBR Green I method. The isolates grew well and L. monocytogens did not grow during the co-culture with those strains at $37^{\circ}C$. Therefore, W. cibaria 0D17 and W. confusa 0D23 might be the candidates as the functional lactic acid bacteria for improving food safety.

• Microbiology and Biotechnology Letters
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• v.30 no.4
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• pp.373-379
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• 2002

By using DL-acetonitrile as enzyme inducer, 90 bacteria were isolated from a field soil. Among the isolated strains, the strain WJ-003 showed the highest activity for production of D-lactic acid from DL-lactonitrile, and was partially identified as Pseudomonas sp. The production condition of D-lactic acid from DL-lactonitrile using resting cells as an enzyme source was optimized as follows: the reaction mixture contained 10 mM of DL-lactonitrile, 20 g of wet cells in 11 of 20 mM potassium phosphate buffer (pH 7.0) and the reaction was carried out at $30^{\circ}C$. After 18 h of reaction, 0.843 g/l of D-lactic acid was produced which corresponded to a conversion ratio of 93.7% and an optical purity of 99.8%. Additionally, when 10 mM of DL-lactonitrile was added once more to the reaction mixture at 14 h, 1.64 g/1 of D-lactic acid was produced after 28 h. In this experiment, the conversion ratio was 91.1% and optical purity 99.8%.

• Microbiology and Biotechnology Letters
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• v.33 no.2
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• pp.106-111
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• 2005

To investigate the substrate variety of a putative non-metal dependent isomerase, the tagatose-6-phosphate isomerase (E.C. 5.3.1.26) structural genes (lacB; 510bp and lacA; 430bp) of Staphylococcus aureus were subcloned and co-expressed. Based on the substrate configuration, various aldoses were surveyed for substrate of ketose isomerization. Among the 10 aldoses tested, D-ribose and D-allose were isomerized by the enzyme. The subunit A and B showed more than $95\%$ activity for D-ribose and $75\%$ for D-allose in the presence of 1mM EDTA compared with non-EDTA conditions, which implying tagatose-6-phosphate isomerase is a non-metal dependent isomerase. Each of subunit A or subunit B alone showed no activity for any of the substrates tested. The affinity constant ($K_m$) of tagatose-6-phosphate isomerase against D-ribose and D-allose were 26 mM and 142 mM, respectively.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.36 no.12C
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• pp.759-763
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• 2011

In this paper, a dual-band T-shaped microstrip monopole antenna with a pair of slits for 2.4/5.2/5.8-GHz wireless local area networks (WLANs) is proposed. A pair of T-shaped slits is loaded on a T-shaped monopole antenna fed by microstrip line in order to obtain dual-band operation as well as to reduce the antenna size. It is demonstrated from experimental results that the proposed antenna can cover all the required bands for WLAN. The measured impedance bandwidth for VSWR<2 is about 5.7% (2.37-2.51GHz) in the lower frequency band and about 28.8% (4.76-6.35GHz) in the higher frequency band. The measured peak gains are about 1.33 dBi to 1.66 dBi in the 2.4GHz band, 3.50 dBi to 3.95 dBi in the 5.25GHz band, and 2.06 dBi to 2.34 dBi in the 5.8GHz band.

• Progress in Medical Physics
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• v.13 no.1
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• pp.27-31
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• 2002

Output factors for 6MeV electron were directly measured under the condition of an individual beam cutout and these factors were compared with the output factors by 1D method which is an easy means to predict the output factors of electron beam. Output factors by 1D method are defined as output factors of rectangular fields where one side is always equal to the side of the square reference field and the output of an arbitrary rectangular field X, Y is given by the product of the 1D output factors. The output of very large square fields is overestimated using 1D method for the 6MeV electron, but it results in agreement with measured data under the condition of an individual cutout within 1% error adopting a correction factor $CF=C\times$[(X-10)(Y-10)/$\mid$(X-10)(Y-10)$\mid^{1/2}]$.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.18 no.2
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• pp.82-90
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• 2019

In this paper, the effects of different 3D printing conditions including oil lubrication and annealing are observed for their effects on tensile testing. In 3D printing, a press-out extrude filament is rapidly heated and cooled to create internal stress in the printed part. The 3D printing internal stress can be removed using oil-coated filament and annealing. During the oven cooling at an annealing temperature of $106^{\circ}C$, the stress of the specimens with laminated angle $0^{\circ}$ tends to increase by 12.6%, and that of the oil-coated filament printing specimens is increased by 17%. At the annealing temperature of $106^{\circ}C$, the stress of the oil-coated filament printing specimens tends to increase by 35%. In this study, we have found that the oil lubrication and annealing remove the internal stresses and increase the strength of the printed specimens. The oil lubrication and annealing reform the crystalline structures to even out the areas of high and low stress, which creates fewer fragile areas. These results are very useful for the manufacture of 3D printing products with a suitable mechanical strength for applications.