• Title/Summary/Keyword: chemical controls

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A Implementation of Web-based Education Contents for 8051 MicroController

  • Kim Hyun Keu;Jun Heung Gu;Choi Kwan Sun
    • Proceedings of the IEEK Conference
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    • 2004.08c
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    • pp.690-692
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    • 2004
  • This paper describes Web based education technique. We implemented a remote compile system with 8051 micro controller. It implemented the system in this paper so that a learner compiled 8051 control programs to the remote. Most big restriction subject is the control of the hardware in an engineering field even though it implements a remote education system. We download the Java Application to Java Web Start and execute in this system. In this paper the learner controls 8051 executions in Web to the remote and implemented so that we confirmed the action. The supplementary problem will be the construction of a remote education system which offeres existing text and sound information, flash animation.

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Development of The New Turf Herbicide Methiozolin (신규 잔디 제초제 메티오졸린(methiozolin) 개발)

  • Koo, Suk-Jin;Hwang, Ki-Hwan;Jeon, Man-Seok;Kim, Sung-Hun;Lim, Jong-Soo;Lee, Dong-Guk;Chung, Kun-Hoe;Ko, Young-Kwan;Ryu, Jae-Wook;Koo, Dong-Wan;Woo, Jae-Chun
    • Korean Journal of Weed Science
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    • v.30 no.4
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    • pp.323-329
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    • 2010
  • Methiozolin (5-(2,6-difluoro-benzyloxymethyl)-5-methyl-3-(3-methyl- thiophen-2-yl)- 4,5-dihydro-isoxazole) is a new turf herbicide in isoxazoline chemistry. The herbicide controls grass weeds and has a high safety to various cool and warm season turfgrasses. This paper describes basic chemical, biological, and regulatory information of methiozolin.

Understanding of Extracellular Fumarate Induced dctA Gene Expression Profile Using GFP Reporter (GFP 리포터를 이용한 외부 푸마르산 유도 dctA 유전자 발현 특성 파악)

  • Irisappan, Ganesh;Ravikumar, Sambandam;Kim, Joo-Han;Hong, Soon-Ho
    • Korean Journal of Microbiology
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    • v.47 no.2
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    • pp.174-178
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    • 2011
  • In Escherichia coli, DcuS/R two-component system controls fumarate import and utilization related gene expression. To understand the dynamic response of the bacterium DcuS/R two-component system with respect to fumarate concentrations, DcuS/R induced dctA promoter was integrated with GFP reporter protein. Expression monitoring study using recombinant strain showed that dctA promoter was upregulated with 1 mM of fumarate in M9 minimal medium.

Oxidative DNA Damage from Nanoparticle Exposure and Its Application to Workers' Health: A Literature Review

  • Rim, Kyung-Taek;Song, Se-Wook;Kim, Hyeon-Yeong
    • Safety and Health at Work
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    • v.4 no.4
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    • pp.177-186
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    • 2013
  • The use of nanoparticles (NPs) in industry is increasing, bringing with it a number of adverse health effects on workers. Like other chemical carcinogens, NPs can cause cancer via oxidative DNA damage. Of all the molecules vulnerable to oxidative modification by NPs, DNA has received the greatest attention, and biomarkers of exposure and effect are nearing validation. This review concentrates on studies published between 2000 and 2012 that attempted to detect oxidative DNA damage in humans, laboratory animals, and cell lines. It is important to review these studies to improve the current understanding of the oxidative DNA damage caused by NP exposure in the workplace. In addition to examining studies on oxidative damage, this review briefly describes NPs, giving some examples of their adverse effects, and reviews occupational exposure assessments and approaches to minimizing exposure (e.g., personal protective equipment and engineering controls such as fume hoods). Current recommendations to minimize exposure are largely based on common sense, analogy to ultrafine material toxicity, and general health and safety recommendations.

Chemical Composition and Active Antioxidants of Eucommia ulmoides Oliv. Bark

  • Qu, Guan-Zheng;Si, Chuan-Ling;Yin, Yu;Wang, Myeong-Hyeon
    • Nutritional Sciences
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    • v.9 no.4
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    • pp.330-334
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    • 2006
  • Chemical composition of the Eucommia ulmoides bark, including extractives, proximate, mineral, fatty acid and monosaccharide compositions, was studied The most abundant mineral was calcium (533.17 mg/l00 g). $\alpha-linolenic$ acid (24.7%) and linoleic acid (24.3%), showed higher contents among the fatty acids. Major monosaccharides of E. ulmoides balk were arabinose (13.94 mg/g), xylose (18.91 mg/g) and glucose (119.7 mg/g). From the bark of E ulmoides, four compounds were isolated and their structures were elucidated as caffeic acid (I), kaempferol (II), quercetin (III) and isoquercitrin (IV) by spectroscopic analysis such as NMR and MS, including cellulose TLC and other chemical evidence such as hydrolyzation and acetylation. The antioxidant activities of four isolated compounds were evaluated by DPPH free radical scavenging, hydroxyl scavenging and reducing power assays. The results indicated that all the isolated compounds showed higher DPPH radical scavenging activity than $\alpha-tocopherol$ and BHT that were used as positive controls and these four compounds exhibited considerable reducing power and hydroxyl radical (OH) scavenging activity. Considering from the results above, it suggests that the E. ulmoides bark is a potential natural source of antioxidant material.

Effect of Ultrasound on the Growth and Short-term Behaviour of the Carp, Cyprinus carpio (초음파가 잉어 Cyprinus carpio의 성장 및 단기적 행동에 미치는 영향)

  • Yoon, Sung-Jin;Yeom, Dong-Hyuk;Kim, Woo-Keun;Yun, Hong-Gil;Lee, Sung-Kyu
    • Korean Journal of Ecology and Environment
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    • v.40 no.2
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    • pp.244-253
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    • 2007
  • In this study, mortality, body wet weight, health assessment, and short-term behavioral mode were observed to determine the effects of ultrasound on the ecological response of the carp Cyprinus carpio. Mortality in the treatments was less than 5% during ultrasound exposure (31 dB re 1 ${\mu}Pa$, $14{\sim}15$ kHz) and there were no significant differences among the replicates (P>0.05). The treatments, based on mean wet weight, exhibited greater effect than the controls, but the magnitude of the differences was not large. Skins and tail fins of some test animals exposed to the controls and intensive treatment groups had light injury such as hemorrhaging, whereas, damages in other organs such as eyes, other fins, parasites, thymus, and gills were not observed (P>0.05). Sudden stimuli in low intensity at a short distance caused a directional avoidance of the fish from the sound. However, the carp exposed to ultrasound at the large scale field was not observed clear behavior changes. Overall results suggest that fish exposed to the low-intensity ultrasound had no serious stress during the tests.

Pest control managements for preservation of wooden cultural properties (목조문화재의 원형보존을 위한 충해 방제방안)

  • Lee, Kyu-Sik;Jeong, So-Young;Chung, Yong-Jae
    • 보존과학연구
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    • s.21
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    • pp.5-55
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    • 2000
  • The cultural properties are damaged by various causes according to the characteristics of material, the condition of preservation, and the period of time. Especially, biodeterioration makes lots of damages in organic properties than inorganic ones. The damages of wooden cultural properties by insects usually are caused by the three orders; Isoptera, Coleoptera, and Hymenoptera. As the result of investigation on the state of 141 buildings of wooden cultural properties in 1999, some of them were damaged by many kinds off actors; wasp, powder post beetle, cigarette beetle, termite, decay, and physical cracking. And it was found that the patterns of damages were related to species-specific habits of insects. There are several methods of pest control for the prevention of wooden cultural properties from damages caused by insects. Those are as follows; physical control, chemical control, biological control, and integrated pest management. When insects and fungi were detected at the wooden buildings, the fumigation is best treatment to stop biodeterioration. And then, wood materials also need to be treated with insecticidal and antiseptic chemicals to avoid a reinfestation, because the fumigant is volatile. The six commercial chemicals which are applied to the insecticidal and antiseptic treatment of wooden cultural properties were purchased to test their abilities. According to the comparative results of efficacy of them in laboratory, chemical D showed excellent efficacy in all items, including antiseptic and termiticidal items. The goal of these pest controls is to protect wooden buildings from insects and microorganisms. The most effective method used currently is chemical control(fumigation, insecticidal and anticeptic chemical treatment), but it has to be treated periodically to control pest effectively. Recently environmentally-friendly control methods such as bait system or biological treatments are replacing traditional barrier treatments using large amounts of chemicals. Especially, termite is a social insect which makes a colony. Although a building with fumigation treatment is safe for a while, once attacked building has a risk of damage by reinfestation of termite. Therefore, to control termites from damaged building, the entire colony including reproductives(queen and king) and larvae around buildings must beeliminated. Bait system can be used as a preventive measure in early detection of them through termites colony monitoring and baiting. It would be the most effective for termite control if bait system would be used together with the chemical controls.

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Development of Direct Analysis of Metal and Non-metal Ions in Aqueous Samples with the Moderate Power Helium Microwave Induced Plasma (중급 출력 마이크로파 유도 플라즈마를 이용한 금속 및 비금속 수용액시료의 직접 분석법의 개발)

  • Park, Yong-Nam
    • Journal of the Korean Chemical Society
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    • v.35 no.6
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    • pp.699-706
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    • 1991
  • The moderate power (500 W) Microwave Induced Plasma was generated with helium gas and was used for the direct analysis of aqueous samples. Usually, the helium plasma obtained with a modified Beenakker type cavity forms a cylindrical one. Though, by the careful controls of gas flows, a "toroidal" shape plasma could be made but its analytical performances were found to be worse. Using the glass frit nebuliser, the detection limits for metal ions obtained were around 10~100 ppb and that for chloride was about 50ppm.

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Necessary optimality conditions in the small for degenerate hyperbolic distributed-parameter control systems

  • Chang, Kun-Soo;Lee, In-Beum
    • 제어로봇시스템학회:학술대회논문집
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    • 1990.10b
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    • pp.1043-1048
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    • 1990
  • The degenerate case of multivariable hyperbolic distributed-parameter systems (systems of hyperbolic partial differential equations) in time coordinate t and space coordinate x is characterized by a property that all the characteristic curves of the state equations are parallel to the coordinate axes of independent variables. It is a disturbing fact, although not well known, that the so-called maximum principle as applied to these systems does not exist for the control that depend on time alone. In this paper, however, it is shown that a set of necessary conditions in the small can exist for unconstrained as well as magnitude constrained controls in a locally convex set. The necessary conditions thus derived can be used conveniently to find the optimal control for degenerate hyperbolic distributed-parameter control systems.

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Energetic Disorder Dependence of Optimal Trap Depth in the Space Charge Field Formation for Photorefractivity

  • Lee, Choong-Keun;Park, Sun-Kyung;Yang, Min-O;Lee, Nam-Soo;Kim, Nak-Joong
    • Bulletin of the Korean Chemical Society
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    • v.28 no.3
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    • pp.447-450
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    • 2007
  • Trap effects on the formation of space-charge field (SCF) associated with the photorefractivity of nonlinear optical polymers were studied by the Monte Carlo simulation using modified Gaussian disorder model. The charge transport dynamics influenced by the presence of trap molecules controls the formation of SCF via the charge distribution. Temporal behavior of SCF formation and SCF dependence on the trap depth are discussed in terms of the concentration and distribution of charges (holes and ionized acceptors) developed following illumination of light. The correlation of the trap depth and the energetic disorder is presented for an optimal efficiency for the SCF formation.