• 기술사
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• 제32권6호
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• pp.94-99
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• 1999

Recently, flood damage is rapidly increasing because of warming of globe, urbanization and industrialization. As a countermeasure to prevent these flood damages, it is quite required to extend the flood control ability by improving the objective rivers in the watershed and building more medium to large scale reserviors. Simultaneously repairing and rehabilitation of facilities through the safety diagnosis for reinforcement of the facilities should be continuously proceeded. Also extensive implementation of drainage improvement, establishment of prevention and refairing system against flood damage and raise of accuracy of weather forecasting should be proceeded.

• 제어로봇시스템학회논문지
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• 제9권4호
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• pp.329-339
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• 2003

A neural network based adaptive controller design method is proposed for reconfigurable flight control systems in the presence of variations in aerodynamic coefficients or control effectiveness decrease caused by control surface damage. The neural network based adaptive nonlinear controller is developed by making use of the backstepping technique for command following of the angle of attack, sideslip angle, and bank angle. On-line teaming neural networks are implemented to guarantee reconfigurability and robustness to the uncertainties caused by aerodynamic coefficients variations. The main feature of the proposed controller is that the adaptive controller is designed with assumption that not any of the nonlinear functions of the system is known accurately, whereas most of the previous works assume that only some of the nonlinear functions are unknown. Neural networks loam through the weight update rules that are derived from the Lyapunov control theory. The closed-loop stability of the error states is also investigated according to the Lyapunov theory. A nonlinear dynamic model of an F-16 aircraft is used to demonstrate the effectiveness of the proposed control law.

• 대한한방소아과학회지
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• 제21권2호
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• pp.89-96
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• 2007

Objectives The purpose of this study is to examine of the effect of Sachunghwan on the liver disease. Methods It was induced liver damage rats by thioacetamide and dosed the extract orally and measured the activity rate of GOT, GPT, ALP and LDH. Results 1. GOT activity was more decreased in the experimental goup than in the control goup. Group I showed continuous significance after 72 hour, Group II was significance after 96 hours. 2. GPT activity was more decreased in the experimental group than in the control group. Group I was effective after 72 hours, but group II was effective after 96 hours. 3. The significance of ALP activity in the Group I and group II was revealed after 72 hours. 4. The significance of LDH activity in the Group I and group II was revealed after 96 hours. Conclusions It was showded that Sachunghwan extract was effective on liver disease.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 2007년도 정기 학술대회 논문집
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• pp.771-776
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• 2007

Widespread propagation of failure can be triggered by localized damage to a structure because of fires, impact and explosion etc. In this paper, the progressive collapse analysis program is developed to automatically check the failed members and construct the modified structural model at each step. OpenSees, that is widely used in many research groups, was used for the developed progressive collapse analysis control program. The control program developed in this study automatically computes the damage indices of all the structural members and performance a progressive collapse analysis after the first failed member is selected. Using the developed program, we compared the progressive collapse behaviors of the example structures considering dynamic effects or not, and the difference of progressive collapse mechanism according to the modeling method of the failed members.

• 한국식품영양과학회지
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• 제27권4호
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• pp.712-717
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• 1998

This study was undertaken to investigate the inhibition effects of Auricularia auricula-judae methanol extract in edible mushroom on lipid peroxidation and liver damage in benzo(a)pyrene(B(a)P)-treated mice. The activities of serum aminotransferase, cytochrome P-450, superoxide dismutase, catalase, glutathione peroxidase and the hepatic content of lipid peroxide after B(a)P-treatment was markedly increased than control but those levels were significantly decreased by the treatment of Auricularia auricula-judae methanol extract. Glutathione S-transferase activity and the hepatic glutathione content were decreased by B(a)P-treatment than control, but those were also inhibited by the treament of Auricularia auricula-judae methanol extract. These results suggest that Auricularia auricula-judae methanol extract have a protective effect on liver damage by B(a)P.

• 한국군사과학기술학회지
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• 제11권2호
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• pp.144-151
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• 2008

An experimental study has been conducted to investigate the effects of circular damage hole on the characteristics of airfoil performance. The damage on a wing created from a hit by anti-air artillery was modeled as a circular hole. Force balance measurements and static pressure measurements on the wing surface were carried out for the cases of having damage holes of 10% chord size at quarter chord and/or half chord positions. All experiments were conducted at Reynolds number of $2.85\times10^5$ based on the chord length. The surface pressure data show big pressure alterations near the circular damage holes. This abnormal surface pressure distribution produces shear stress that could lead to the acceleration of the structural degradation of the wing around the circular damage hole. However, in spite of the existence of circular damage holes, the measured force data indicated the only a slight decrease in lift accompanied by increase in drag compared to the results of undamaged one. The influence of damage hole on the aerodynamic performance was increased as the location of damage moved to the leading edge. The effect on the control force was insignificant when the damaged size was not large.

• Journal of Microbiology and Biotechnology
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• 제14권3호
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• pp.466-469
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• 2004

The recombinant bioluminescent Escherichia coli strains, DPD2511 and TV 1061 containing the katG and grpE promoters, respectively, from Vibrio fischeri fused to luxCDABE, were used to detect the adaptive and repair responses to oxidative damage caused by hydrogen peroxide $(H_2O_2)$, and protein damage due to phenol. The response ratio, represented as the bioluminescence induced in subsequent inductions of DPD2511 and TV1061 with the mother cells previously induced by each chemical, i.e., $H_2O_2$ and phenol during the previous induction stage, decreased suddenly compared with the ratio of the control culture of each strain, meaning there is a possible adaptive response to stress caused by chemicals. Protein damage due to phenol was completely repaired by the second culturing after the initial induction, as was oxidative damage caused by $H_2O_2$ which was also rapidly repaired, as detected by the recovery of bioluminescence level. This result suggests that E. coli promptly adapt and repair oxidative and protein damage by $H_2O_2$ and phenol completely.

• Food Science and Biotechnology
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• 제18권1호
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• pp.179-184
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• 2009

The aim of this study was to investigate effects of onion, red onion, or quercetin on plasma antioxidant vitamin, lipid peroxidation, and leukocyte DNA damage in rats fed a high fat-cholesterol diet. Forty SD male rats were assigned to normal control, high fat-cholesterol diet (HF), or HF+5% onion powder, HF+5% red onion powder, or HF+0.0l% quercetin. The HF diet resulted in significantly higher plasma lipid peroxidation which decreased with onion, red onion, or quercetin supplementation. Leukocyte DNA damage induced by HF diet decreased significantly in rats fed onion and red onion, while quercetin supplementation had no effect on preventing leukocyte DNA damage. $H_2O_2$ induced leukocyte DNA damage exhibited a highly significant negative correlation with plasma retinol and tocopherols. These results suggest that onion or red onion powder exerts a protective effect with regard to DNA damage in rats fed HF diet. However, 0.01% quercetin in pure form might not be effective at preventing DNA damage.

• Smart Structures and Systems
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• 제5권1호
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• pp.43-54
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• 2009

This study introduces a novel approach for locating damage in a structure using wireless sensor system with local level computational capability to alleviate data traffic load on the centralized computation. Smart wireless sensor systems, capable of iterative damage-searching, mimic an optimization process in a decentralized way. The proposed algorithm tries to detect damage in a structure by monitoring abnormal increases in strain measurements from a group of wireless sensors. Initially, this clustering technique provides a reasonably effective sensor placement within a structure. Sensor clustering also assigns a certain number of master sensors in each cluster so that they can constantly monitor the structural health of a structure. By adopting a voting system, a group of wireless sensors iteratively forages for a damage location as they can be activated as needed. Since all of the damage searching process occurs within a small group of wireless sensors, no global control or data traffic to a central system is required. Numerical simulation demonstrates that the newly developed searching algorithm implemented on wireless sensors successfully localizes stiffness damage in a plate through the local level reconfigurable function of smart sensors.

• Journal of Ecology and Environment
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• 제48권3호
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• pp.374-381
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• 2024

Background: There is a wide range of phenotypic plasticity in plants that respond to tissue damage. Compensatory growth after physical damage may function as a part of tolerance to herbivory, which is affected by resource limitations and/or damage properties. Results: Under different light availability (unshaded and shaded) and damaged leaf ontogeny (control, young leaf- and mature leaf-damaged), compensatory growth was examined for the herbal vine Aristolochia contorta. Under the unshaded treatment, compensatory growth on leaf and branch emergence was strongly induced compared to the shaded treatment. Damage to young leaves induced leaf emergence more strongly than damage to old leaves. Conclusions: It appears that light availability acted as a limiting factor in the compensatory growth of A. contorta after the damage despite its vigorous growth under the shade treatment. Under the shade, leaf damage led to altered biomass allocation as indicated by a decrease in specific leaf area and an increase in root mass fraction. The present study contributes to the understanding of the phenotypic plasticity of vine species under different environmental conditions and damaged tissue, which may differ depending on the species' habitat range.