• Journal of the Korean Society for Nondestructive Testing
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• v.18 no.4
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• pp.278-291
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• 1998

Fracture process of continuous fiber reinforced composites is very complex because various fracture mechanisms such as matrix cracking, debonding, delamination and fiber breaking occur simultaneously during crack growth. If fibers cause crack bridging during crack growth, the stable crack growth and unstable crack growth appear repeatedly. Therefore, it is very difficult to exactly determine tile starting point of crack growth and the fracture toughness at the critical crack length in composites. In this research, fracture toughness test for CFRP was accomplished by using acoustic emission(AE) and recording of tile fracture process in real time by video-microscope. The starting point of crack growth, pop-in point and the point of unstable crack growth can be exactly determined. Each fracture mechanism can be classified by analyzing the fracture process through AE and video-microscope. The more reliable method ior the fracture toughness measurement of composite materials was proposed by using the combination of R-curve method, AE and video microscope.

• Applied Biological Chemistry
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• v.35 no.6
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• pp.507-512
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• 1992

A ${\beta}-1,3-glucanase$ of soybean (Glycine max) was isolated, and the effects of benzyladenine(BA) on celluar levels of the enzyme content and activity were studied. The effects of BA on callose content in cell wall and wall regeneration of protoplasts were also studied to show promoting effect of cytokinin in cell wall regeneration and to elucidate action mode of cytokinin. The polypeptide of 21 kD was identified as ${\beta}-1,3-glucanase$, and the cellular content and activity of this polypeptide were decreased by BA treatment. The callose content in cell wall of callus and the wall regeneration of protoplasts were increased by BA treatment. These results indicate that cytokinin promotes cell wall regeneration by inhibition of callose degradation via decreasing ${\beta}-1,3-glucanase$ level in cell.

• Journal of Intelligence and Information Systems
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• v.15 no.3
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• pp.119-136
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• 2009

According to the increase of container flows and the appearance of large-sized container vessels, the container handling equipment in ports is evolving continuously. This research introduces the simulation model for evaluating in detail the mechanical productivity of container cranes. The model considers a single trolley and dual trolleys as the mechanism of a container crane and a single lift, a twin lift, and a tandem lift as the spreader type of it. Additionally, the detail specifications such as the dimension and the speed of a container crane are inputted and the kinematic characteristics of it are simulated. The model also considers the size of a vessel, the storage position of containers in the vessel, and the weight of containers as external physical constraints. Experimental conditions can be configured conveniently because various parameters in the model are separated. Moreover, the model can accommodate flexibly new equipment types and the changes of the existing equipment because it is designed and developed in object-oriented concept.

• Journal of Institute of Control, Robotics and Systems
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• v.17 no.8
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• pp.814-823
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• 2011

Nowadays many neurological diseases such as stroke and Parkinson diseases are continually increasing. Orthotic devices as well as exoskeletons have been widely developed for supporting movement assistance and therapy of patients. Robotic knee orthosis can compensate stiff-knee gait of the paralyzed limb and can provide patients consistent assistance at wearable environments. With keeping a robotic orthosis wearable, however, it is not easy to develop a compact and safe actuator with fast rotation and high torque for consistent supports of patients during walking. In this paper, we propose a novel kinematic model for a robotic knee orthosis to drive a knee joint with independent actuation during swing and stance phases, which can allow an actuator with fast rotation to control swing motions and an actuator with high torque to control stance motions, respectively. The suggested kinematic model is composed of a hamstring device with a slide-crank mechanism, a quadriceps device with five-bar/six-bar links, and a patella device for knee covering. The quadriceps device operates in five-bar links with 2-dof motions during swing phase and is changed to six-bar links during stance phase by the contact motion to the patella device. The hamstring device operates in a slider-crank mechanism for entire gait cycle. The kinematics and velocity/force relations are analyzed for the quadriceps and hamstring devices. Finally, the adequate actuators for the suggested kinematic model are designed based on normal gait requirements. The suggested kinematic model will allow a robotic knee orthosis to use compact and light actuators with full support during walking.

• Journal of Korea Game Society
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• v.9 no.1
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• pp.43-54
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• 2009

This paper is written for analyzing the history of the Korean game legislation system. The regulation system of amusement place business that is discussed in this paper was started at the Enforcement Rule of the Amusement Place Act of 1973. It was maintained till 1999 and comes under the quickening period of the current game legislation. The legal regulation of this times was accomplished through the Amusement Place Act, the Amusement Place Business Act and the Public Health Act. The amusement place business was differentiated into the athletics facility business, the amusement facility business and the game proffer business of current legislations. The game proffer business succeeds to the kernel of the regulation system of amusement place business. Therefore, The basis of the current game legislation was constituted in the times of the regulation system of amusement place business. Two cores of the regulation system of amusement place business, (1) the separation of the amusement instrument and the speculation, (2) the regulation of a place of business, are still the important issues of the current game legislation.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.6 no.8
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• pp.1200-1205
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• 2002

Construction of Private networks is becoming easier due to the openness of telecommunication market, rapidly developing telecommunication technology. The size of existing private networks is becoming huge which resulted in surplus of capacity of the networks. These trends will generate a problem of efficient use of national telecommunication resources and which will be a factor for the structure of domestic telecommunication market which will have a big impact on the existing telecommunication carriers. Therefore, national policy of private network issues should be considered along with the national efforts for the information infrastructure, control of telecommunication market, fairness of competition, strength Power of national competition. In this paper it will be suggested that the efficient policy on the issue of domestic private network, by analyzing present situation, status quo, laws, regulation and procedure for domestic private networks and comparing it with those of U.S.A, Japan, EU.

• The Korean Journal of Zoology
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• v.13 no.3
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• pp.75-84
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• 1970

Gamma-radiolyses of oxygenated and deoxygenated glycylglycylclycine in aqueous solution and in the solid state are observed, with special regards to peptied bond rupture for elucidation of radiolytic mechanism of proteins, by means of chromatorgraphic separation of degradation products, spectrophotometric quantitation of carbonyl compounds, micro-titration of amide formation, infrared spectrophptometry, and ultraviolet spectrophotometry for evaluation of radiation damage. Essential difference of peptide bond rupture is observed in solution and in the solid state, being high in the former and negligible in the latter. On the other hand, the presence of and obsence of oxygen in solution during irradiation are not so significant with respect to peptide bond rupture, except the recombination of free-radicals produced in deoxygenated solution. Peptide bond rupture in solution is attributable to the mechanisms proposed by Garrison et al.; dehydrogenation followed by hydrolysis to yield acid amide and carbonyl function as found on the basis of radiolytic products. Peptide bond attack at $\\alpha$-carbon locus might be suggestive for irradiated solid but not significant in view of low degree of peptide bond rupture.

• Korean journal of applied entomology
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• v.32 no.3
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• pp.265-270
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• 1993

The German cockroach(Blattelia germanica) population~ were successIVely selected with ch\orpyrifos and permethrin during the six generations. The resulting resistant $R_{chtorpenfos}$(Rc) and $R_{permethnn}$(Rp) stra.ins were studied to investigate the esterase activity by spectrophotometer, filter parper test, and electrophoresis. Esterase-$\alpha$ activities by filter paper test showed 2.65 and LBZ times higher in the Rc and Rp strains than the susceptible strain, respectively. ln the spectrophoLometer method, the esterase activit18s to $\alpha$-and $\beta$-naphthyl acetate were increased 2.34 and 5.28 times in the Rc than susceptible strain, and 1.48 and 2.92 times in the Rp Limn susceptible stram, respectlvely. Zymogram patterns of eslerase isozyme by agarose gel electrophoresis showed totally five bands. The Rc and Rp strains showed two additive bands as, Est-2 and Est-3, which were not shown in the susceptible strain. but the Rp strain dId not show Est-5 bands which was COlumon in the Rc and susceptible strams.

• Applied Chemistry for Engineering
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• v.5 no.1
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• pp.127-138
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• 1994

In the process of pervaporation separation for aqueous ethanol solution through cellulose tai-acetate(CTA) membrane, the modelling on the solution-diffusion permeation mechanism was built up on the basis of sorption and permeation experimental results. Also its function type and parameter were examined. The composition of sorption equilibrium in three component system(Ethanol/Water/CTA) were compared with the calculated value by Flory-Huggins' equation using the pure component sorption data. In order to apply the thermodynamic equilibrium relationship between the membrane free composition in the membrane and the equilibrium composition in the liquid phase, the apparent activity this system, however, the results were not satisfied. Diffusion equations were expressed with the concentration gradient considering permeate alone, and a concentration-dependent diffusion coefficient which includes a parameter was used. And this model was fitted with the measured permeation rates. If the permeation rate and the amount of sorption of one component were much larger than those of the other, the bulk flow term could not be negligible. The flux and selectivity were increased with increasing temperature, and with decreasing downstream pressure.

• Korean Journal of Weed Science
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• v.10 no.3
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• pp.233-239
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• 1990

The effect of alachlor treatment on peroxidase synthesis in oat root tips was studied. Alachlor caused increase in the amount of soluble peroxidase in oat root tips, peroxidase activity increase as the rate of alachlor application increased, Alachlor treatment of oats with $1{\times}10^{-6}M$, peroxidase activity increased 0.20 unit higher than that of nontreatment. After 12hr, 65mM of peroxide treatment of oats inhibited 16% root growth, and 130 mM peroxide treatment caused 59% inhibition. With PAGE of peroxidase extracted from normal root tips, PAGE give 4 species($P_2$, $P_3$, $P_4$, and $P_5$ band) of peroxidase. Alachlor significantly activated isoperoxidase. Three isoperoxidase($P_1$, $P_6$, and $P_7$) are synthesized at a increased concentration of alachlor, SDS-PAGE analysis of proteins extracted from oat root tips showed that they were made up of subunits blow 100 kD polypeptide.