• Microbiology and Biotechnology Letters
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• v.4 no.4
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• pp.145-151
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• 1976

Cultural characteristics of a strain of Streptomyces sp. K-14 (KFCC 35051) producing glucose isomerase were demonstrated. The glucose isomerase was produced when the strain was grown in the medium containing pure xylan or xylan.containing materials such as wheat bran or com cob. The optimum condition was attained in a culture medium composed of 3 % wheat bran or com cob, 2 % com steep liquor, 0.1% $MgSO_4$$7H_2O$ and 0.012 % $CoSO_4$$7H_2O$ for the production of the glucose isomera,e. The production of the enzyme reached to a maximum level when the strain was cultured for 40 hrs $30^{\circ}C$ and pH 7.0.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.37 no.5
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• pp.476-485
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• 1992

M1 plants which were produced from seed soaking in chemical mutagen, EMS or NaN$_3$, appeared wide morphorogical variations such as dwarf, albino, twisted leaf, white streaked leaf, and purpled stem. In mutants of reproductive organs, there were monoecious plants such as female-flower plant and male-flower plant, multiple spikes, and steriled plants among M1 plants. Also, barren stalk was increased significantly in M1 plants. Ear bagging at ear initiation stage prevented seed set on cob in normal plants. In spite of ear bagging, M1 plants which had cobs with seed set was 3.9-11.2% of stalks developed from seeds soaking with mutagens, but only three or four kernels could be matured on a cob. Ear bagging after mutagen injection into initiating ear produced 5.1-10% in cobs with seed set, but only 1.7-6.3 kernels could be matured. Cobs removed silk at four hours after artificial pollination increased the rate of cobs with seed set to 27%. Microscopic observation confirmed that ontogeny of kernels matured from ear bagging and mutagen treatment would be both adventitious and diplosporous apomictic reproduction. Chromosome set of M2 seedling was found to be diploid type in chromosomal counting of root tip. As M$_2$ plants showed an uniform appearence within each lines and their CV of plant height were ranged 4-6% in each lines, we concluded that they were apomictic progeny. But we could not find any marker traits combined with apomixis.

• Journal of The Korean Society of Grassland and Forage Science
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• v.25 no.3
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• pp.177-184
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• 2005

This study was conducted to study the effect of fiber sources on ruminal pH and buffering capacity and whole digestive tract digestibility with five ruminally fistulated sheep. Evaluated fiber sources were alfalfa hay cube (AHC), corn cob (CC), com silage (CS), cotton seed hull (CSH), peanut hull (PHL), rice straw (RS), and sugarcane bagasse (SCB). Sheep were fed consecutively a diet containing each tested fiber source $(45\%)$ with a corn-based concentrate diets $(55\%)$ during each experimental period. Ruminal pH showed no difference among fiber sources except the significantly lower pH at 8h (p<0.05) with RS (pH; 5.78) than those in other sources. Buffering capacity showed significant differences at 0h (p<0.05) and 2h (p<0.05) after feeding in CS compared to those from SCB and CC, while there was higher in PHL (p<0.01) at 12h post feeding except AHC than CC, CS, SCB, and RS. Dry matter digestibility was significantly higher in CS (p<0.001) than in other sources. Neutral detergent fiber digestibility was higher in CC, CS, CSH, and RS than other fiber sources (p<0.001). These results suggest that ruminal pH and buffering capacity and whole digestive track digestibility were significantly affected by fiber sources in ruminant diet, and, therefore, should be took those effects into account for TMR formulation.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.26 no.1
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• pp.66-73
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• 2017

This study attempted to design lights with Type II distribution suitable for LED street lights based on the regulations of street light distribution developed by the Illuminating Engineering Society of North America (IESNA). The shape of an asymmetric lens, different from that of a rotationally symmetric lens, cannot be generated using a simple mathematical formula. In the first trial, the outline of the lens was fixed and simulated to confirm the distribution type. Following ISENA regulations, some problems that occurred during simulations and repeating was be modified that process is how we detected errors. Through optical research and simulations, a lens conforming to the regulations of Type II very short, Type II short, and Type II medium distributions was developed. A prototype was developed using simulation data and it was subjected to distribution tests. The results show that it can compare with property of Type II distribution.

• Structural Engineering and Mechanics
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• v.74 no.4
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• pp.533-545
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• 2020

An optimal design method for a spoke double-layer cable-net structure (SDLC) is proposed in this study. Simplified calculation models of the SDLC are put forward to reveal the static responses under vertical loads and wind loads. Next, based on an energy principle, the relationship among the initial prestress level, cross-sectional areas of the components, rise height, sag height, overall displacement, and relative deformation is proposed. Moreover, a calculation model of the Foshan Center SDLC is built and optimized. Given the limited loading cases, material properties of the components, and variation ranges of the rise height and sag height, the self-weight and initial prestress level of the entire structure can be obtained. Because the self-weight of the cables decreases with increasing of the rise height and sag height, while the self-weight of the inner strut increases, the total weight of the entire structure successively exhibits a sharp reduction, a gradual decrease, a slow increase, and a sharp increase during the optimization process. For the simplified model, the optimal design corresponds to the combination of rise height and sag height that results in an appropriate prestress level of the entire structure with the minimum total weight.

• Journal of Korean Society for Atmospheric Environment
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• v.2 no.2
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• pp.19-30
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• 1986

This study was performed to develop a long-term air pollution dispersion model based on CDM program for use in the personal computer. The model CDM.PC, developmented for use of this study, simplified the plum equation of point pollution source in a windy state and sindless state. We used the classified 8 class stability, 16 wind direction and 4 class wind speed for the computer input climatological data. The plum rise equation is applied for CONCAWE's equation above 2,000 Kcal/sec of the exhaust calorie and Moses-Carson's equation below 2,000Kcal/sec at windy state, and Brigg's equation at calm. The time required is 200 minutes for drawing the air pollution contour for treating ten stacks under the above-stated conditions. It is the weakness of using personal computer that the operation time is longer than a large-size computer. But it strength is that the personal computer is used widely. To compare the treatment results of CDM.PC with TCM, we comfirmed that the shape of $SO_2$ pollution contour is similar but the concentration distribution is quite different because of characteristics of each models. Estimated and measured $SO_2$ concentration were similar, namely, Cest/Cob ratio of CDM.PC and TCM were respectively $0.96 \pm 0.25 (mean\pmS.D)$ and $1.08\pm0.26$.

• Journal of Information Technology Services
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• v.10 no.2
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• pp.141-162
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• 2011

The controls of Information Systems (IS) have been an more critical issue controls as the sophistication and integration of IS is more proceeded. ITGI (The Information Technology Governance Institute) of ISACA (Information Systems Audit and Control Association) has suggested COBIT (Control Objectives for Information and related Technology) and this has been widely recognized the evaluation model of IS controls. In COBIT, IS was evaluated in terms of process, information quality, and IT resources. This study used COBIT in order to suggest and empirically test an evaluation model of IS service. The data was collated from one major Chinese SI (Systems Integration) company in four domains of processes : planning and organization, acquisition and implementation, delivery and support, and monitoring. Seven factors are extracted using an exploratory factor analysis as follows : Overall IT planning process, technological assessment process in IT planning of IT, cost-benefit assessment process in IT planning, implementation process, support process, monitoring process, post-implementation evaluation process. The results of confirmatory analysis of three alternative measurement models indicated that the measurement model with one inherent or conceptual variable has greater model fitness than the other models. This study suggests the logical and general way to test and apply COBIT in evaluating IS services.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2006.11a
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• pp.221-221
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• 2006

The SMD type P-N junction diode with ceramic package for diode case were fabricated. It was made this diode with simple process from $Al_2O_3$ ceramic chip, solder preform, diode chip, coating reagent and conductive paste for chip terrmination. Its merit is small size, easy manufacture. fast cooling with ceramic case. The electric characteristics of the diode such as reverse recovery time, breakdown voltage, forward voltage, and leakage current were 5 28ns, 1322V, 1.08V, $0.45{\mu}A$.

• International Journal of Naval Architecture and Ocean Engineering
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• v.9 no.3
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• pp.292-304
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• 2017

High-speed vessels are prone to the surf-riding in adverse quartering seas. The possibility of mitigating the surf-riding of the ITTC A2 fishing vessel in the design stage is investigated using the 6-DOF weakly non-linear model developed for surf-riding simulations in quartering seas. The longitudinal position of the ship's center of buoyancy (LCB) is chosen as the design parameter. The adjusting of LCB is achieved by changing frame area curves, and hull surfaces are reconstructed accordingly using the Radial Basis Function (RBF). Surf-riding motions in regular following seas for cases with different LCBs and Froude numbers are simulated using the numerical model. Results show that the surf-riding cannot be prevented by the adjusting of LCB. However, it occurs with a higher threshold speed when ship's center of buoyancy (COB) is moved towards stem compared to moving towards stern, which is mainly due to the differences on wave resistance caused by the adjusting of LCB.

• Mycobiology
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• v.43 no.1
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• pp.14-23
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• 2015

The influences of temperature and nutritional conditions on the mycelium growth of oyster mushroom Pleurotus ostreatus (PO) and Pleurotus cystidiosus (PC) were investigated in laboratory experiment during the summer season of 2014. The results of the experiment indicated that potato dextrose agar (PDA) and yam dextrose agar (YDA) were the most suitable media for the mycelium growth of oyster mushroom PO while four media (PDA, YDA, sweet potato dextrose agar, and malt extract agar medium) were not significantly different in supporting mycelium growth of oyster mushroom PC. The optimal temperature for mycelium growth of both oyster mushroom species was obtained at $28^{\circ}C$. Mycelium growth of oyster mushroom PO was improved by carbon sources such as glucose, molasses, and at 1~5% sucrose concentration, mycelium colony diameter of mushroom PO was achieved the highest value. Whereas glucose, dextrose, and sucrose as carbon sources gave the good mycelium growth of oyster mushroom PC, and at 1~3% sucrose concentration, mycelium colony diameter of PC was achieved the maximum value. Ammonium chloride concentrations at 0.03~0.09% and 0.03~0.05% also gave the greatest values in mycelium colony diameter of mushroom PO and PC. Brown rice was found to be the most favourable for mycelium growth of two oyster mushroom species. In addition, sugarcane residue, acasia sawdust and corn cob were selected as favourable lignocellulosic substrate sources for mycelium growth of both oyster mushrooms.