• Animal cells and systems
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• v.6 no.3
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• pp.247-252
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• 2002

The effect of paraquat (PQ, 1,1＇-dimethyl-4,4＇-bipyridium) on the histogene-sis and glycoconjugates (GCs) properties of the pyloric region of the stomach in a perinatal rat was examined by histological and histochemical methods. Oral administration of PQ (9 mg/kg per day in 0.2 mL of D.W.) on 7 to 14 days of gestation revealed growth retardation with significant reductions in the length of pyloric gland and their pit. As for histochemical properties of GCs in the pyloric region of the stomach, the PQ-treated rats showed some differences, such as delayed initial appearance of the sulfated GCs and lectin affinities compared with the vehicle group. These different GCs properties in the surface and gastric pit were usually detected in the fetal rats and more prominent and evident differences were revealed in the gland epithelium of the early postnatal rat. These results suggest that maternal PQ administration causes intrauterine growth retardation asso-ciated with delayed histogenesis and GCs immaturation of pyloric mucosa in developing rat.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.26 no.8
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• pp.1487-1494
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• 2002

In this study, to propose the prediction method of the crack growth under flight-simulation loading, crack growth tests are conducted on 2124-7851 aluminum alloy specimens. The prediction of crack growth under flight-simulation loading is performed by the stochastic crack growth model which was developed in previous study. First of all, to reduce the complex load history into a number of constant amplitude events, rainflow counting is applied to the flight-simulation loading wave. The crack growth, then, is predicted by the stochastic crack growth model that can describe the load interaction effect as well as the variability in crack growth process. The material constants required in this model are obtained from crack growth tests under constant amplitude loading and single tensile overload. The curves predicted by the proposed model well describe the crack growth behavior under flight-simulation loading and agree with experimental data. In addition, this model well predicts the variability of fatigue lives.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.21 no.4
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• pp.80-87
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• 2007

This paper will suggest that the 1 cross orthogonal loop type sensor improves on the orthogonal loop form sensor-head, which is available a calibration of the linear birefringence, when a fiber optic current sensor was composed. An output characteristics of the 1 cross orthogonal loop form, a general closed loop form, the orthogonal loop form are compared by the IEC(International Electrotechnical Commission) 60044-8 standard, and the state of polarization is compared with three forms. As a result, when the closed loop form was changed to the orthogonal loop form, retardation decreased 15.3[%]. When the closed loop form was changed to the 1 cross orthogonal loop type, the retardation decreased 33.8[%]. As a result of the Faraday Effect measurement, the 1 cross orthogonal loop form has the highest output characteristic and the lowest error ratio. It met the 0.5 class of the IEC 60044-8 standard. Thus, in application of the 1cross orthogonal loop form, the possibility to develop high reliability fiber optic current sensors that have a high output and stable error ratio rises is increased.

• The Journal of Pediatrics of Korean Medicine
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• v.24 no.1
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• pp.36-45
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• 2010

Objectives The purpose of this study is to evaluate the effect of herbal medicine in children's growth and to report the children's expectation. Methods 171 children visited the department of Pediatrics, Kyung-Hee Oriental Medical Hospital from June 2009 to December 2009 were studied. They were treated more than 6 months and they visited our clinic more than 3 times. Every time when patients visited our hospital, their height, body weight and obesity degree was examined using DS-102(dszenix, Seoul). Also, height percentile of first and the last visit was measured, and those were compared by the Growth Statistics Curve made by the Korean Association of Pediatrics, 2007. Results and Conclusions The mean growth of total children increased by 4.42 percent; the increased percent for boys was 4.17 and that of girls was 5.00. Herbal medical treatment helped growth in children who took medicine for growth retardation problem. Plus, majority of parents who visited the department of Pediatrics, Oriental Medical Hospital satisfied with the service and their children's height. Although thinking genetic factor is important for their height, but they think that herbal medical treatment help the growth with changing eating habit.

• Journal of the Korea Institute of Building Construction
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• v.13 no.2
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• pp.122-130
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• 2013

One of recent methods to protect wooden cultural assets from fire, there is the flame retardation which is applied directly to wood and it is to prevent fire through securing flame resistance for the material and delaying combustion when failed fire in advance and then to gain time for people in the room to evacuate and it has same goal with the Korean Fire Service Act by protecting life and property. However, in case of spraying flame retardant on the colored surface of the wooden cultural assets, there are continuous problems of decoloration, efflorescence and water absorbtion after sometime and accordingly there increases danger of damages of cultural assets. So when treating with flame retardant on wooden cultural assets, there has to be no problems on dancheong after sometime and securing sustainable methods for flmae retardation should be preceded. Accordingly, this study aims to provide basic sources for selecting proper flame retardation methods by evaluating and analyzing flame retardation capabilities according to types of flame retardants which are frequently used nowadays and spraying them on the dancheong-painted surface and confirming if there is no problem on the dancheong and wood after sometime and if flame retardation effect is sustainable with its quality and capability through precise analysis.

• Korean Journal of Food Science and Technology
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• v.47 no.6
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• pp.797-800
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• 2015

The effect of raw wheat flour on starch retrogradation retardation was investigated in a rice starch paste model. Specifically, in terms of amylase activity present in the wheat flour, the retardation effect was investigated depending on reaction temperature (40, 60, and $80^{\circ}C$), incubation time (0, 20, 40, and 60 min), and wheat flour addition levels (0-10%). An increase in wheat flour concentration resulted in a rapid decrease in the elastic modulus (G') as the incubation time increased. The G' changes of the rice starch pastes were furthermore fitted by the first order reaction for the reaction rate estimation on the temperature basis. The experimental reaction rate of the paste sample incubated with 10% wheat flour at $40^{\circ}C$ exhibited good agreement with the predicted value. This result implied that the first order reaction kinetics could be suitable to predict the changes in the G' as a function of incubation temperature and wheat flour concentration.

• Journal of the Korean Ceramic Society
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• v.24 no.3
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• pp.289-295
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• 1987

The changes of physical properties of portland cement pastes and mortars were investigated by addition of sodium gluconate. Flow table experiment and viscosity measurement were took in order to find dispersing effect, and time-dependent changesof viscosity and rates of hydration heat evolution were carried out for the sake of finding retardation effect of hydration. And changes of physical properties of cement pastes and mortars were discussed by setting time, compressive strength and porosity.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1994.10a
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• pp.826-830
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• 1994

Making Brinell indentations facing each other near the crack tip is very effective method in increasing fatigue life. In this paper, fatigue test was performed after indentation to investigate the effect of thickness of specimen. The results show that fatigue lives increased my making indentation and retardation cycle is inverse proportional to thickness of specimen.

• KSTLE International Journal
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• v.1 no.1
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• pp.52-58
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• 2000

The velocity and motion of single air bubbles rising through lubricant have been experimentally investigated to test the effect of silicon defoamant The investigation reveals that the velocity is markedly retarded by the addition of small amount of silicone defoamant. This retardation of rising velocity of air bubbles is proposed by increasing of Drag force or reducing of Buoyancy force around the surfaces of the bubbles.

• Journal of the Korean institute of surface engineering
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• v.32 no.2
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• pp.134-143
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• 1999

The effects of silicon on galvannealing behavior of interstitial-free (IF) steels were studied. The growth rate of the Fe-Zn alloy layer was retarded as silicon in the steel added. Titanium in steel strongly favors Fe-Zn reaction, in particular outburst structures, whereas silicon inhibit them. Cross-sectional and planar views of galvannealed coatings were investigated to characterize alloy phase development. A possible mechanism to explain the retardation effect of silicon is discussed in terms of concentration on surface and inhibition layer.