• Title/Summary/Keyword: 차단효율

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Analysis and Improvement Strategies for Korea's Cyber Security Systems Regulations and Policies

  • Park, Dong-Kyun;Cho, Sung-Je;Soung, Jea-Hyen
    • Korean Security Journal
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    • no.18
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    • pp.169-190
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    • 2009
  • Today, the rapid advance of scientific technologies has brought about fundamental changes to the types and levels of terrorism while the war against the world more than one thousand small and big terrorists and crime organizations has already begun. A method highly likely to be employed by terrorist groups that are using 21st Century state of the art technology is cyber terrorism. In many instances, things that you could only imagine in reality could be made possible in the cyber space. An easy example would be to randomly alter a letter in the blood type of a terrorism subject in the health care data system, which could inflict harm to subjects and impact the overturning of the opponent's system or regime. The CIH Virus Crisis which occurred on April 26, 1999 had significant implications in various aspects. A virus program made of just a few lines by Taiwanese college students without any specific objective ended up spreading widely throughout the Internet, causing damage to 30,000 PCs in Korea and over 2 billion won in monetary damages in repairs and data recovery. Despite of such risks of cyber terrorism, a great number of Korean sites are employing loose security measures. In fact, there are many cases where a company with millions of subscribers has very slackened security systems. A nationwide preparation for cyber terrorism is called for. In this context, this research will analyze the current status of Korea's cyber security systems and its laws from a policy perspective, and move on to propose improvement strategies. This research suggests the following solutions. First, the National Cyber Security Management Act should be passed to have its effectiveness as the national cyber security management regulation. With the Act's establishment, a more efficient and proactive response to cyber security management will be made possible within a nationwide cyber security framework, and define its relationship with other related laws. The newly passed National Cyber Security Management Act will eliminate inefficiencies that are caused by functional redundancies dispersed across individual sectors in current legislation. Second, to ensure efficient nationwide cyber security management, national cyber security standards and models should be proposed; while at the same time a national cyber security management organizational structure should be established to implement national cyber security policies at each government-agencies and social-components. The National Cyber Security Center must serve as the comprehensive collection, analysis and processing point for national cyber crisis related information, oversee each government agency, and build collaborative relations with the private sector. Also, national and comprehensive response system in which both the private and public sectors participate should be set up, for advance detection and prevention of cyber crisis risks and for a consolidated and timely response using national resources in times of crisis.

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The Effects of Negative- and Positive- Charged Surfactants on In vitro DM Digestibility and the Growth of Ruminal Mixed Microorganisms (양(+) 이온성 및 음(-) 이온성 계면활성제 첨가가 반추위 혼합 미생물에 의한 In vitro 건물소화율 및 미생물 성장에 미치는 영향)

  • Lee, S.J.;Shin, N.H.;Kim, W.Y.;Moon, Y.H.;Kim, H.S.;Ha, J.K.;Lee, S.S.
    • Journal of Animal Science and Technology
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    • v.49 no.5
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    • pp.647-656
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    • 2007
  • In order to investigate the effects of supplemental ionic surfactants in in vitro ruminal fermentation, N-Lauroylsarcosine sodium salt(N-LSS) and sodium dodecyl sulfate(SDS) for negative(-) ionic surfactant, and hexadecylpyridinium chloride monohydrate(HPCM) and hexadecyltrimethyl ammonium bromide(HTAB) for positive (+) ionic surfactant were supplemented by 0.05% and 0.1% into the Dehority’s artificial medium containing rice straw(1mm) as a substrate. In vitro DM digestibility, the growth of rumen mixed microbes, pH, cumulative gas production and SEM(Scanning Electron Microscopy) observation of microbial attachment on rice straw particle were investigated through the experiment composing 9 treatments (two supplemental levels of two positive ionic(+) surfactant, two supplemental levels of two negative(-) ionic surfactant) including the control. The sample collection was at 6, 12, 24, 48 and 72 h post fermentation with 3 replications per treatments. DM digestibility in treatments supplemented (+) or (-) surfactants almost stopped afterward 12 h fermentation, in vitro DM digestibility at 72 h post fermentation in the ionic surfactants was at half level of that of the control(P<0.05). Accumulative gas production in in vitro was less(P<0.05) with addition of ionic surfactants compared to the control. The amount of rumen mixed microbes recovered from in vitro incubation fluid pleateaued at 12 h post fermentation for the positive (+) ionic surfactants, but steadily increased as fermentation time elapsed for the control. Rumen microbial growth rate was significantly(P<0.05) low in the negative(-) ionic surfactant compared to the control. pH of the incubation fluid was ranged from 6.02 to 7.20, and was the highest in the negative(-) ionic surfactants, and was the lowest in the control(P<0.05). In SEM observation, rumen microbial population attached on rice straw particle was less with addition of ionic surfactants than the control. In conclusion we could not found any positive effects of negative- and positive- charged surfactants on rumunal fermentation characteristics and rumen microbial growth rates.

Road-map for Environmental Friendly Integrated Pest Management(IPM) of Insect Pests on the Strawberry Vinyl-houses of Farmer's Field (딸기재배 하우스에서 발생하는 해충의 환경친화적 종합적방제를 위한 로드맵)

  • Lee, D.H.;Jo, C.W.;Park, C.R.;Lee, H.J.;Kang, E.J.;Seok, H.B.;Seo, M.J.;Kim, H.Y.;Kim, Y.H.;Yu, Y.M.;Youn, Y.N.
    • Korean journal of applied entomology
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    • v.47 no.3
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    • pp.273-286
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    • 2008
  • Road-map for the environmental friendly integrated pest management(IPM) of insect pests was drawn up on the strawberry vinyl-houses of farmer's field. Major insect pests were occurred Tetranychus urticae and Aphis gossypii during the strawberry plant seeding in the vinyl house and open field. Also, same insect pests were occurred in the vinyl house during harvesting season of strawberry. For the control of T. urticae and A. gossypii, Phytoseiulus persimilis and Aphidius colemani as natural enemies were input to the vinyl house, respectively. However, because these natural enemies could not control insect pest populations, acaricide and insecticide were sprayed. Then natural enemies were input again in the vinyl house. Natural enemies could not endure the intense cold and differences of temperature and relative humidity between day and night during strawberry harvesting season. So, their behavior and control activity of pests were more decrease than pests. Firstly, natural enemies are input in the vinyl house during the early breeding season of strawberry, secondly, acaricides and insecticide are sprayed for the control of mites and aphids, respectively, during the middle breeding season in the hard winter. Finally, natural enemies are re-input in the vinyl house during the middle and late breeding season.

Analysis of the Insulation Effectiveness of the Thermal Insulator by the Installation Methods (보온단열재의 설치방법에 따른 보온성 효과 분석)

  • Kim, Young-Bok;Lee, Si-Young;Jeong, Byoung-Ryong
    • Journal of Bio-Environment Control
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    • v.18 no.4
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    • pp.332-340
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    • 2009
  • In this study, the thermal insulation effectiveness of the greenhouse insulators by the installation methods was investigated to find the right installation way of the insulation materials. Physical properties of the insulators such as thickness, air transmissivity, apparent density, ultraviolet rays cutoff ratio, reflectance, thermal conductivity, moisture absorptivity were evaluated and the insulation ability of the insulators were measured by the module experiments. For the same insulator, the insulation ability of the case with the outward direction of the black colored face, i.e., with the inward direction of the white colored face, was better than that of vice versa. The case of the black colored both surfaces was better than the case of the white colored both surfaces. For aluminium reflection material, the case with the outward direction of the lustre face, i.e., with the inward direction of the non-lustre face, was better than that of vice versa. For the same material with the inner thin polyethylene foam (or polyester) and the chemical wool, the case with the outward direction of the inner thin polyethylene foam (or polyester), i.e., with the inward chemical wool, was better than that of vice versa. Addition of the inner thin polyethylene foam increased the insulation effect very much.

THE PREVALENCE OF WHITE SPOT LESIONS ON THE MESIAL SURFACES OF THE 1ST MOLARS IN CHILDREN AND MINIMAL INVASIVE APPROACH - A PILOT STUDY (어린이 제1대구치 근심면 초기 우식의 유병률과 최소 침습적 접근)

  • Ahn, Myung-Ki;Lee, Geum-Lang;Jeong, Tae-Sung;Kim, Shin
    • Journal of the korean academy of Pediatric Dentistry
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    • v.36 no.1
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    • pp.102-107
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    • 2009
  • In clinical pediatric dentistry, we have many chances to encounter the white spot like incipient enamel lesions on the mesial surfaces of the 1st molars with direct vision, especially just after the 2nd primary molars were exfoliated. But it was thought highly desirable to assess if these lesions are properly and effectively managed yet. This study aims at surveying the prevalence of incipient lesions on the mesial surfaces of the 1st molars in children through direct observation and examining the suitability of adhesive sealing on them as a pilot trial in searching for their proper management. 1. Among the 124 mesial surfaces of the 1st molars examined, 34% were sound, 53% had incipient carious lesions and 13% had cavitated lesions. 2. In the sectional views of the specimens, 20% showed microleakage after thermo-cycling and it was thought not recommendable as a permanent method. Therefore in order to effectively fight against the incipient caries lesions in children‘s permanent teeth, it was thought proper not to rely on any one method, but to perform reinforcing oral hygiene and promotion of remineralization in combination with therapeutic sealing which is stronger in short-term sealing effect. Although therapeutic sealing has been considered as the core in minimally invasive concept to treat the white spot lesions, its long-term clinical trials have not been suggested. Continuous research is strongly required for making this approach to acquire permanent nature, especially in regards of proper pretreatment and high molecular materials deeply penetrable into enamel.

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Study of Solidification by Using Portland and MSG(micro silica grouting) Cements for Metal Mine Tailing Treatment (금속 광미 처리를 위한 포틀랜드 시멘트와 MSG(micro silica grouting) 시멘트 고형화 실증 실험 연구)

  • Jeon, Ji-Hye;Kim, In-Su;Lee, Min-Hee;Jang, Yun-Young
    • Economic and Environmental Geology
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    • v.39 no.6 s.181
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    • pp.699-710
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    • 2006
  • Batch scale experiments to investigate the efficiency of the solidification process for metal mine tailing treatment were performed. Portland and MSG (micro silica pouting) cements were used as solidifier and three kinds of mine tailings (located at Gishi, Daeryang, and Aujeon mine) were mixed with cements to paste solidified matrices. Single axis com-pressible strengths of solidified matrices were measured and their heavy metal extraction ratios were calculated to investigate the solidification efficiency of solidified matrices created in experiments. Solidified matrices ($5cm{\times}5cm{\times}5cm$) were molded from the paste of tailing and cements at various conditions such as different tailing/cement ratio, cement/water ratio, and different cement or tailing types. Compressible strengths of solidified matrices after 7, 14, and 28 day cementation were measured and their strengths ranged from 1 to $2kgf/mm^2$, which were higher than Korean limit of compressible strength for the inside wall of the isolated landfill facility ($0.21kgf/mm^2$). Heavy metal extractions from intact tailings and powdered matrices by using the weak acidic solution were performed. As concentration of extraction solution for the powdered solidified matrix (Portland cement + Gishi tailing at 1:1 w.t. ratio) decreased down to 9.7 mg/L, which was one fifth of As extraction concentration for intact Gishi tailings. Pb extraction concentration of the solidified matrix also decreased to lower than one fourth of intact tailing extraction concentration. Heavy metal extraction batch experiments by using various pH conditions of solution were also performed to investigate the solidification efficiency reducing heavy metal extraction rate from the solidified matrix. With pH 1 and 13 of solution, Zn and Pb concentration of solution were over the groundwater tolerance limit, but at pH $1{\sim}13$ of solution, heavy metal concentrations dramatically decreased and were lower than the groundwater tolerance limit. While the solidified matrix was immerged Into very acidic or basic solution (pH 1 and 13), pH of solution changed to $9{\sim}10$ because of the buffering effect of the matrix. It was suggested that the continuous extraction of heavy metals from the solidified matrix is limited even in the extremely high or low pH of contact water. Results of experiments suggested that the solidification process by using Portland and MSG cements has a great possibility to treat heavy metal contaminated mine tailing.

A Study on 'Verfremdung' effects in visual advertisements with a special reference to the <017-I-Touch series, The Hand Transformed into a Web >, mobile network advertisement (동영상 광고에서 나타나는 '소격화' 효과에 관한 연구 - 광고 <017-I-Touch편 (손이 물갈퀴) >를 중심으로 -관어영시광고중소출현적‘맥생화’효과적연구(關於影視廣告中所出現的‘陌生化’效果的硏究))

  • Jin, Ri-Long;Ahn, Sang-Soo;Kim, Jong-Deok
    • Archives of design research
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    • v.18 no.2 s.60
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    • pp.37-46
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    • 2005
  • Today's advertisement is dominated by visual images, which deliver messages in the most efficient and engaging way. Vivid and live images, through multimedia, attract the viewer to consume the products being advertised. In this course, the effect of 'Verfremdung' or alienation is often detected. This terminology was at first used in a epic play of Bertolt Brecht to signify a specific effect to block the empathy of the audience by reminding them of their position as the audience separate from the play. 'Verfremdung' helps them to have a sense of objectivity and critical attitude toward the performance. Multimedia commercials nowadays exhibit such a quality together with 'viewer participation:' criticism on reality: and 'speed.' In an advertisement for Shinsegi Communications' mobile system titled <017-I-Touch series, the hand transformed into a web>, the copy, 'my blood type is 'i', ' is accompanied by six unrelated fictitious scenes in which the same ocean appears as a common denominator. Because there is no connection between the scenes, free imagination of the viewer has to be involved and thus plays a significant role in making them into a context. This fact dearly exhibit some characteristics of post- modern advertisement. Momentary 'Gap' and 'Difference' between scenes contribute to 'Verfremdung' or alienation' that makes it hard for the consumers to comprehend the content on the spot. Such an uneasy situation, however, keeps the viewers thinking about the advertisement itself. While repeatedly exposed to the alienated images, the viewers come to get involved in the advertisement, trying to make the fragmented images into a coherent context. In addition, the leaps between the scenes produce a sense of 'speed' in a context, which adds more impact to the way of delivering messages using multimedia. With the help of multimedia, 'Verfremdung: which was originally intended to bring about objective and critical altitude of the audience in a play, plays a crucial role in attracting the viewer's attention and conveying a specific message in a moment in contemporary advertisement.

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Hazard Analysis of Tomato Farms at the Growing Stage for the Establishment of the Good Agricultural Practices (GAP) (토마토 농산물우수관리제도(GAP)모델 확립을 위한 재배단계 위해분석)

  • Park, Su-Hee;Kwon, Woo-Hyun;Heo, Rok-Won;Kim, Kyeong-Yeol;Shim, Won-Bo;Shim, Sang-In;Chung, Duck-Hwa
    • Journal of Food Hygiene and Safety
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    • v.27 no.2
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    • pp.152-160
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    • 2012
  • The objective of this study was to analyze hazards for the growing stage of 6 tomato farms (A, B, C; soli farms, D, E, F; Nutriculture farms) located in Gyeongsangnam-do to establish the good agricultural practices (GAP). A total of 144 samples for analyzing hazards collected from cultivation environments (irrigation water, soil, nutrient solution, and air) and personal hygiene (hands, gloves, and cloths) were assessed for biological (sanitary indications and major food borne pathogens) and chemical hazards (heavy metals). Total bacteria, coliform, and fungi were detected at levels of 0.2-7.2, 0.0-6.1, and 0.0-5.4 log CFU/g, mL, hand or 100 $cm^2$, respectively. Escherichia coli were only detected in the soil sample from B farm. In case of pathogens, Bacillus cereus was detected at levels of 0.0-4.4 log CFU/(g, mL, hand or 100 $cm^2$), whereas Staphylococuus aureus, Listeria monocytogenes, E. coli O157, and Salmonella spp. were not detected in all samples. Heavy metals as a chemical hazard were detected in soil and irrigation water, but levels of them were lower than the permit limit. In conclusion, chemical hazard levels complied with GAP criteria, but biological hazards at the growing stage of tomato farms were confirmed. Therefore a proper management to prevent microbial contamination is needed.

Inhibitory Effects on the Enzymes Involved in the Inflammation by the Ethanol Extracts of Plant Foodstuffs (식물성 일반식품 자원의 에탄올 추출물이 염증 효소계에 미치는 영향)

  • Kwon, Eun-Sook;Kim, Il-Rang;Kwon, Hoon-Jeong
    • Korean Journal of Food Science and Technology
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    • v.39 no.3
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    • pp.348-352
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    • 2007
  • Inflammation is a complex process resulting from a variety of mechanisms. Combined inhibition of the activities of enzymes involved in the process may therefore be considered more important in anti-inflammatory property of plant extracts than any single contribution. In this study, the inhibitory effects of the ethanol extracts of thirty plant foods on the activities of secretory phospholipase $A_{2}$ ($sPLA_{2}$), cyclooxygenase-1 (COX-1), cyclooxygenase-2 (COX-2), and 12-lipoxygenase (12-LOX) were examined. Several legumes, mungbean sprout and some leaf vegetables inhibited the activity of $sPLA_2$, upstream enzyme of inflammation pathway. Only soybean sprout and mungbean sprout significantly inhibited 12-LOX activity. Although most of extracts inhibited the activities of both COX-1 and COX-2, water dropwort and amaranth showed selectivity for the inhibition of COX-2 over COX-1. Especially, mungbean showed anti-inflammatory property at both upstream and downstream of inflammation pathway with relatively low $IC_{50}$ values for $sPLA_{2}$ and COX-2 enzymes. Mungbean sprout exhibited inhibitory effects on all enzymes related to early and late inflammation and soybean sprout suppressed 12-LOX and COX-2 simultaneously, although the activities of these plants were showed at relatively high concentration. Therefore, mungbean, mungbean sprout, and soybean sprout appear to exhibit anti-inflammatory effects by combined inhibition of inflammatory enzymes.

Effect of Activated Carbon, Orpar or Zeolite on Leaching Loss of Fenitrothion, Triadimefon and Diniconazole in Model Green of Golf Course (골프장 모형그린에서 활성탄, Orpar또는 Zeolite의 처리가 Fenitrothion, Triadimefon, Diniconazole의 용탈에 미치는 영향)

  • Oh, Sang-Sil;Koh, Yong-Ku;Chung, Jong-Bae;Hyun, Hae-Nam
    • Applied Biological Chemistry
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    • v.44 no.2
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    • pp.97-102
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    • 2001
  • Cheju island depends on a hydrogeologically vulnerable aquifer system as its principle source of drinking water. Most of golf courses are located in the area which is important for the ground water recharge, and pesticides are applied to golf courses often at relatively high rates. Therefore, turf pesticides in golf course should be applied without adversely impacting ground water. In this experiment, downward movement of pesticides was monitored in model greens of golf course, where different adsorbents were layered in 3-cm thickness at 35-cm depth, and effect of the adsorption layer on the leaching loss of pesticides was investigated. Major leachings were observed in the periods of heavy rain and very limited leaching was observed under artificial irrigation. Fenitrothion and triadimefon, which have relatively short persistence and high adsorption coefficient, were found in the leachate in low concentrations only at the first rainfall event, around 20 days after the pesticide application. However, diniconazole, which has a relatively long half-life (97 days), was detected in the leachate during the whole period of experiment and concentration was much higher than those of the other pesticides. Maximum leachate concentrations were 1.9, 10.3, and 84.5 ${\mu}l^{-1}$ for fenitrothion, triadimefon, and diniconazole, respectively. Therefore, in golf course green which allows rapid water percolation and has extremely low adsorption capacity, persistence in soil could be more important factor in determination of leaching potential of pesticides. Total quantity of pesticides leached from the model green was <0.2% for fenitrothion and triadimefon and 1.8% for diniconazole. Adsorption layers significantly reduced pesticide leaching, and active carbon and Orpar were more effective than zeolite. In the model green having adsorption layer of active carbon or Orpar, leaching loss of pesticides was reduced below 0.01% of the initial application.

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