• Journal of Radiation Industry
• /
• v.7 no.2_3
• /
• pp.109-113
• /
• 2013

In a previous study, a relatively high dose of gamma radiation (1 kGy) did not fully induce typical SOS genes such as sulA, recA, recN, and din in Salmonella Typhimurium (S. Typhimurium) (Lim et al. 2008, Gene expression profiles following high-dose exposure to gamma radiation in Salmonella enterica serovar Typhimuium. J. Radiat. Ind. 3:111-119). In this study, we examined changes in the transcriptional repertoire of S. Typhimurium after a dose of 10 Gy using DNA microarrays. It was found that more than half (~65%) of the 26 up-regulated genes belong to the SOS regulon: ten genes are typical SOS genes, and seven genes are Salmonella prophage genes, which are known to be activated by LexA cleavage. Among 29 down-regulated genes, the function of five genes with the most decreased expression is associated with carbohydrate transport and energy production. This suggests that upon exposure to gamma radiation cells may cease growing by reducing the metabolic activity, and repair DNA damage using a DNA repair system such as the SOS response system. The difference in expression of the SOS genes between a high (1 kGy) and low (10 Gy) dose of radiation shows the possibility that cells may opt for one of multiple regulatory circuits in response to the specific gamma radiation dose.

• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.26 no.5D
• /
• pp.849-859
• /
• 2006

Earnings of domestic enterprises are expected a serious damage because the lowest cost bid system and the current cost estimate system. In 2005 average successful bid rate for the lowest cost bid project is below 60%, this is not reach at the operating budget of enterprise. Many problems such as illegal construction, low price subcontract, chain enterprise loss com in to practice because of low successful bid rate. In addition earnings of the enterprises expected to be the minimum, because of enlarge execution of the current cost estimate system. This study tries to lend assistance by giving alternative for the construction enterprise by presenting the bid system, investigate and compare foreign system with domestic and analyze correlation of the lowest cost bid and the current cost estimate system.

• Journal of the Korean Society for Nondestructive Testing
• /
• v.36 no.5
• /
• pp.345-352
• /
• 2016

As aircrafts are being operated at high altitude, wing structures experience various fatigue loadings under cryogenic environments. As a result, fatigue damage such as a crack could be develop that could eventually lead to a catastrophic failure. For this reason, fatigue damage monitoring is an important process to ensure efficient maintenance and safety of structures. To implement damage detection in real-world flight environments, a special cooling chamber was built. Inside the chamber, the temperature was maintained at the cryogenic temperature, and harmonic fatigue loading was given to a wing structure. In this study, piezoelectric active-sensing based guided waves were used to detect the fatigue damage. In particular, a beamforming technique was applied to efficiently measure the scattering wave caused by the fatigue damage. The system was used for detection, growth monitoring, and localization of a fatigue crack. In addition, a sensor diagnostic process was also applied to ensure the proper operation of piezoelectric sensors. Several experiments were implemented and the results of the experiments demonstrated that this process could efficiently detect damage in such an extreme environment.

• The Journal of Fisheries Business Administration
• /
• v.50 no.2
• /
• pp.23-40
• /
• 2019

The main purpose of this study is to analyze and examine the problems of the law systems of the safety and maintenance of nuclear facilities and to propose the improvements with respect to the related problems especialy focused on safety management of aquatic products. Therefore, the results of the paper would be helpful to build an effective management law system of safety and maintenance of nuclear facilities and fisheries products. The research methods are longitudinal and horizontal studies. This study compares domestic policies with foreign policies of nuclear plants and aquatic products. Using the above methods, examining the current system of nuclear-related laws and regulations, we have found that there exist 13 Acts including "Nuclear Safety Act", etc. Safety laws related on nuclear facilities have seven Acts including "Nuclear Safety Act", "the Act on Physical Protection and Radiological Emergency", "Radioactive waste control Act", "Act on Protective Action Guidelines against Radiation in the Natural Environment", "Special Act on Assistance to the locations of facilities for disposal low and intermediate level radioactive waste", "Korea Institute of Nuclear Safety Act". "Act on Establishment and Operation of the Nuclear Safety and Security Commission". The seven laws are composed of 119 legislations. They have 112 lower statute of eight Presidential Decrees, six Primeministrial Decrees and Ministrial Decrees, 92 administrative rules (orders), 6 legislations of local self-government aself-governing body. The concluded proposals of this paper are as follows. Firstly, we propose that the relationship between the special law and general law should be re-established. Secondly, the terms with respect to law system of safety and maintenance of nuclear plants should be redefined and specified. Thirdly, it is advisable to re-examine and re-establish the Law System for Safety and Maintenance of Nuclear Facilities. and environmental rights like the French Nuclear Safety Legislation. Lastly, inadequate legislation on the aquatic pollution damage should be re-established. It is necessary to ensure sufficient transparency as well as environmental considerations in the policy decisions of the Korean government and legislation of the National Assembly. It is necessary to further study the possibilities of accepting the implications of the French legal system as a legal system in Korea. In conclusion, the safety management of nuclear facilities is not only focused on the secondary industry and the tertiary industry centering on power generation and supply, but also on the primary industry, which is the food of the people. It is necessary to prevent damage to be foreseen. Therefore, it is judged that there should be no harm to the people caused by contaminated marine products even if the "Food Safety Law for Prevention of Radiation Pollution Damage" is enacted.

• Proceedings of the KIEE Conference
• /
• 1991.07a
• /
• pp.478-481
• /
• 1991

This paper discusses the principle and structure of instantaneous voltage drop compensator, which protects damage from instantaneous voltage drop in systems such as computer, variable speed drive, high voltage discharge-lamp, magnet switch. When instantaneous voltage drop occurs, control circuits detect it, then produce output voltage the same as normal condition voltage. Instantaneous voltage drop compensator has condenser bank as energy storage component, so system can be made small, light weight compared with UPS. In normal state, utility source transfers power, and in instantaneous voltage drop state, the energy of condenser bank transfers power through inverter, so high efficiency, compact, and especially low cost system can be manufactured.

• Journal of Nutrition and Health
• /
• v.30 no.3
• /
• pp.244-251
• /
• 1997

The effects of Artemisia princeps var orientalis(mugwort), Circium japonicum var ussuriense (Unggungqui) on cadiovascular system in hyperlipidemic rats were investgated. Thirty rats devided into 5 experimental groups, were fed with the diet contained 1% chlesterol, 0.25% sodium cholate, 10% coconut oil and 5% lard by the same method of previous paper1). Contractile and relaxation responses in the isolated artria and thoracic aortae were measured and the morphological changes of the aortic endotherium from the rats were inspected. The responses of the right atrial to isoproterenol were significantly lower value in Ungungqui powder diet group(UP) and mugwort powder diet group(MP) than the control. The contraction force by injectin of phenylephrine and calcium in isolated thoracic aortae was significantly low value in the UP and the MP groups compaired to the control. The relaxation rate by acetylcholine in isolated thoracic aortae represented significantly higher value in UP than control. The morphological changes of endothelial cell suface was smallest in UP and the damage of endothelium by retarded in MP. Although Ungungqui and mugwort extract diet groups(UE, ME) were advanced, those were less than control.

• Journal of Power System Engineering
• /
• v.18 no.5
• /
• pp.74-79
• /
• 2014

This article aims at investigating the effect of applied load and sliding speed on wear behavior of thermally spraryed STS316 coating. STS316 coatings were fabricated by flame spray process according to optimal parameters on steel substrates. Dry sliding wear tests were performed on STS316 coating using four different applied load as 10, 15, 20 and 25 N and four different sliding speed as 15, 30, 45 and 60 rpm. Wear behavior on worn surface was investigated using scanning electron microscope(SEM) and energy disperive X-ray spectroscopy(EDS). The dominant wear mechanism of STS316 coating under low applied load and sliding speed was oxidation on worn surface. However, under high applied load and sliding speed the principal wear mechanism was abrasion on oxidation film and damage of oxidation film.

• Transactions of the Korean Society of Automotive Engineers
• /
• v.3 no.2
• /
• pp.112-121
• /
• 1995

Various CAE technologies are used in automobile industries for the purpose of design and analysis. In this paper, a fatigue life evaluation system FLEVA based on the local strain approach is developed and the system is applied for the fatigue strength design of the suspension knuckle, an automobile component. Various steps such as material test, finite element analysis and cumulative fatigue damage analysis of the suspension knuckle were taken. The usefulness of the approach was verified by the fatigue test on the suspension knuckle.

• 한국정보디스플레이학회:학술대회논문집
• /
• 2007.08a
• /
• pp.190-192
• /
• 2007

A neutral beam system has been developed to produce hyperthermal neutral beams composed of indium, tin, and oxygen atoms. Using these hyper thermal neutral beams with energies in the range of tens of eV, high quality indium-tin oxide (ITO) thin films have been obtained on glass substrates at room temperature. The optical transmittance of the films is higher than 85% at a wavelength of 550 nm and the electrical resistivity is lower than $1{\times}10^{-3}{\Omega}cm$.

• Proceedings of the KIEE Conference
• /
• 2005.07e
• /
• pp.79-81
• /
• 2005

Chemical methods for moisture contents detection of insulation system in transformer must dismount equipment for sampling, and there is shortcoming such as acquiring partial data for measuring. Also the samples can't immediately analyze in field. The Recovery Voltage Method (RVM) will be able to measure a moisture contents at low voltage without dismounting equipment. Therefore, in advanced countries RVM would be used to measure the moisture contents which permeates to the insulation system without weighting additive degradation or mechanical damage. In this paper we have investigated for overcoming these shortcomings using the RVM, and we have measured the moisture contents of transformer insulation with temperature.