• Title/Summary/Keyword: Mechanism of spread

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Efficient Multicasting Mechanism for Mobile Computing Environment (산불 발생지역에서의 산불 이동속도 예측 및 안전구역 확보에 관한 연구)

  • Woo, Byeong-hun;Koo, Nam-kyoung;Oh, Young-jun;Jang, Kyung-sik;Lee, Kang-whan
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2015.05a
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    • pp.89-92
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    • 2015
  • In this paper, we propose a method to reduce the fire suppression time. Our suggestions can secure a safe area according to the diffusion path and speed of the fire, forest fire prediction minimize casualties and property damage forests. The existing path prediction method wildfire spread predict the wildfire spread model and speed through topography, weather, fuel factor and the image information. In this case, however, occur to control a large mountain huge costs. Also Focus on the diffusion model predictions and the path identified by the problem arises that insufficient efforts to ensure the safe area. In this paper, we estimate the moving direction and speed of fire at a lower cost, and proposes an algorithm to ensure the safety zone for fire suppression. The proposed algorithm is a technique to analyze the attribute information that temperature, wind, smoke measured over time. According to our algorithm forecast wildfire moving direction and ensure the safety zone. By analyzing the moving speed and the moving direction of the simulated fire in a given environment is expected to be able to quickly reduce the damage to the forest fire fighters.

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A review of effect and how to use xylitol (자일리톨의 효과 및 활용방법에 대한 고찰)

  • Shin, Kyoung-Hee;Ahn, Yong-Soon
    • Journal of Korean society of Dental Hygiene
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    • v.10 no.6
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    • pp.1095-1105
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    • 2010
  • Objectives : This paper is designed to help the public prevent their future dental caries, based on the studies of xylitol about it's efficacy and effectiveness, and its appropriate usage. Methods : This study of xylitol on the basis of existing research papers and literature is not only to learn about the mechanism of what xylitol acts, but also to search the effectiveness of incompleteness of xylitol-containing foods, bacterial infection between xylitol and mother-baby, and the side-effects of xylitol. Results : 1. Xylitol's continuous intake of teeth effects the decrease of calculus amount, cleanness of teeth, as well as the remineralization process. The xylitol effect varies depending on the weight of xylitol, which has no effect on root caries. 2. Mouth gargle solution is higher resistant against acids; recalcification is significantly reduced; and remineralization effect represents. 3. It is reported that regular consumption of xylitol by mothers just during two years after birth has significantly decreased the spread possibility of mutans streptococcei. 4. The reduction of dental caries by xylitol is happened by its restraining the growth of bacteria resource caries, with their presence in amount of uncontrolled growth. 5. When a small amount of eating xylitol is absorbed slowly into gastrointestinal tract, being followed by glucose metabolism in the liver, while its excessive amount of eating can cause gastrointestinal problems. Conclusion : Dental hygienists should be required to provide dental information to the public on the basis of academic knowledge. In situation that one is not yet sure of xylitol on solid and multifaceted researches, there must be needed more accurate and detailed reviews on the side-effects of xylitol and the overall impact on the oral environments.

Ultimate behavior of long-span steel arch bridges

  • Cheng, Jin;Jiang, Jian-Jing;Xiao, Ru-Cheng;Xiang, Hai-Fan
    • Structural Engineering and Mechanics
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    • v.14 no.3
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    • pp.331-343
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    • 2002
  • Because of the increasing span of arch bridges, ultimate capacity analysis recently becomes more focused both on design and construction. This paper investigates the static and ultimate behavior of a long-span steel arch bridge up to failure and evaluates the overall safety of the bridge. The example bridge is a long-span steel arch bridge with a 550 m-long central span under construction in Shanghai, China. This will be the longest central span of any arch bridge in the world. Ultimate behavior of the example bridge is investigated using three methods. Comparisons of the accuracy and reliability of the three methods are given. The effects of material nonlinearity of individual bridge element and distribution pattern of live load and initial lateral deflection of main arch ribs as well as yield stresses of material and changes of temperature on the ultimate load-carrying capacity of the bridge have been studied. The results show that the distribution pattern of live load and yield stresses of material have important effects on bridge behavior. The critical load analyses based on the linear buckling method and geometrically nonlinear buckling method considerably overestimate the load-carrying capacity of the bridge. The ultimate load-carrying capacity analysis and overall safety evaluation of a long-span steel arch bridge should be based on the geometrically and materially nonlinear buckling method. Finally, the in-plane failure mechanism of long-span steel arch bridges is explained by tracing the spread of plastic zones.

Detection Trend of Helminth Eggs in the Strata Soil Samples from Ancient Historic Places of Korea

  • Seo, Min;Chai, Jong-Yil;Kim, Myeung Ju;Shim, Sang Yuk;Ki, Ho Chul;Shin, Dong Hoon
    • Parasites, Hosts and Diseases
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    • v.54 no.5
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    • pp.555-563
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    • 2016
  • For several years, we have conducted a series of studies on the patterns of ancient parasitism prevailing in the soil of rural and urban areas of past Kingdom of Korea. Actually, during our survey of paleoparasitology in archaeological sites of Korean peninsula, numerous ancient parasite eggs were discovered in the samples from the city districts of Hansung (Joseon) and Buyeo (Baikje), the palace moat at Gyeongju (Silla), shell-midden site at Bonghwang-dong (Silla to Joseon), and the reservoir found in Hwawangsansung fortress (Silla). By the paleoparasitological studies, with respect to parasitism in the high-density populations of ancient towns and cities, we have managed to catch glimpses of the patterns prevalent therein: a serious parasitic contamination of the soil in ancient urban areas, but not in rural areas of the past. Our historical research also proposed the plausible mechanism of parasite infection very serious indeed among urban populations in Korean history. Although city dwelling doubtless has accrued significant benefits for people and populations with agriculture, it can be equally supposed that living in such highly populated areas might have facilitated the spread of parasite infection.

Nano-sized Drug Carriers and Key Factors for Lymphatic Delivery

  • Choi, Ji-Hoon;Lee, Yong-Bok
    • Journal of Pharmaceutical Investigation
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    • v.40 no.spc
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    • pp.75-82
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    • 2010
  • Specific diseases like cancer and acquired immune deficiency syndrome (AIDS) occur at various organs including lymphatics and spread through lymphatic system. Thus, if therapeutic agents for such diseases are more distributed or targeted to lymphatic system, we can obtain several advantages like reduction of systemic side effect and increase of efficacy. For these reasons, much interest has been focused on the nature of lymphatics and a lot of studies for lymphatic delivery of drugs have been carried out. Because lymphatics consist of single layer endothelium and have high permeability compared with blood capillaries, especially, the studies using nano-sized carriers have been performed. Polymeric nano-particle, liposome, and lipid-based vehicle have been adopted for lymphatic delivery as carriers. According to the administration route and the kind of carrier, the extent of lymphatic delivery efficiency of nano-sized carriers has been changed and influenced by several factors such as size, charge, hydrophobicity and surface feature of carrier. In this review, we summarized the key factors which affect lymphatic uptake and the major features of carriers for achieving the lymphatic delivery. Lymphatic delivery of drug using nano-sized carriers has many fold improved ability of lymphatic delivery compared with that of conventional dosage forms, but it has not shown whole lymph selectivity yet. Even though nano-sized carriers still have the potential and worth to study as lymphatic drug delivery technology as before, full understanding of delivery mechanism and influencing factors, and setting of pharmacokinetic model are required for more ideal lymphatic delivery of drug.

Screening of Antifungal Microorganisms with Strong Biological Activity against Oak Wilt Fungus, Raffaelea quercus-mongolicae

  • Hong, A Reum;Yun, Ji Ho;Yi, Su Hee;Lee, Jin Heung;Seo, Sang Tae;Lee, Jong Kyu
    • Journal of Forest and Environmental Science
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    • v.34 no.5
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    • pp.395-404
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    • 2018
  • Since the mass mortality of Quercus mongolica has been first reported in Gyeonggi province at 2004, the disease spread rapidly over Korean peninsula annually. Ambrosia beetle (Platypus koryoensis) was known as the insect vector of oak wilt fungus, Raffaelea quercus-mongolicae, and control methods of the disease had mainly been focused on eradication of insect vector. However, for the efficient management of the disease, combined control methods for both of the pathogenic fungus and insect vector are strongly required. As one of the efforts to suppress the pathogenic fungus, antifungal activities of Streptomyces isolated from oak forest soil were assayed in this study. Optimum culture condition for the selected isolates was also studied, As a result, Streptomyces blastmyceticus cultured in PDB (Potato Dextrose Broth) at $25^{\circ}C$ for 1 week showed the strongest antifungal activity against oak wilt fungus. Mycelial growth inhibition rates (MGIRs) of Streptomyces isolates were compared on culture media supplemented with heated and unheated culture filtrates of S. blastmyceticus. MGIRs on culture media with unheated culture filtrates were generally higher than those on culture media with heated culture filtrates. Antagonistic mechanism to get involved in the inhibition of hyphal growth and spore formation of the pathogen is due to the antifungal metabolites produced by Streptomyces. This study will provide the fundamental information in developing biocontrol agents for the environment-friendly management of oak wilt disease.

Development of BiPbAgSrCaCuO Superconductor used diffusion of dual layer and The growth mechanism process of superconducting phase (이중층 시료에서 확산을 이용한 BiPbAgSrCaCuO 초전도체 개발 및 초전도상 성장기구)

  • Choi, S.H.;Gang, H.G.;Yu, H.S.;Yu, J.J.;Choi, M.H.;Kim, M.K.;Choi, H.S.;Han, T.H.;Park, S.J.;Hwang, J.S.;Han, B.S.
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 1993.05a
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    • pp.22-27
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    • 1993
  • we prepared 70K new BiPbAgSrCaCuO superconductor used diffusion of dual layer which composed of SrCaCuO and BiPbAgCuO compound. This method is used permeation and diffusion on partial melting point of BiPbAgCuO compound. Samples were analyzed by means of X-ray diffraction analysis, Thermal analysis, critical temperature and scanning electron microscopy. It was found that the best results were obtained for spread volume (A:B=1:0.6) and sintring time 210hours.

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Analysis on the Cultural Phenomena related to the Depiction of Women's Costume in Korean Modern Novels (한국근대소설의 여성복식에 나타난 문화현상 분석)

  • Jeon, Hyun-Sil;Hong, Na-Young
    • Journal of the Korean Society of Costume
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    • v.61 no.6
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    • pp.38-59
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    • 2011
  • This study is based on the periodical discourse of women and their costumes, described in modern novels that were published from late 1890s to the 1930s. New cultural phenomena emerged among Korean women in the period of modernization. In particular, rapid increase of jobs for women and preference for western female body shape are very noticeable phenomena that can be observed in novels of the 1930s. In addition, the symbolic meanings of female costumes are variously described in modern novels according to the periodical and spatial environment and jobs for women. The symbolic meanings are organized as 'Trophysm, Expression of sexuality, Liberation from male-dominated society, Symbolic difference between rural and urban areas, Vanity, Decadence, Mechanism tending to hide and Change of values'. And women's costumes kept changing in the boundary of 'Confliction, Coexistence and Harmonization' of traditional and western costumes. 'Confliction' phenomenon got emerged in novels published between 1900 and 1910. The resistance on traditional costumes that restricted woman's life got spread. But western female costumes as a symbol of new culture could not be generalized but accepted as high fashion. 'Coexistence' phenomenon was appeared in novels of the 1920s. At that time, the modernization for traditional costumes by female students was emerged along with trendy fashion. Also, the frequency of using western fashion items was increased in the Korean society. Therefore, it shows that western costumes in the Korean society became popularized in the coexistence with traditional costumes. 'Harmonization' phenomenon was emerged in novels of the 1930s. In the novels, the emergence of western female costumes, personal preference items, and westernized hair style implies that western costumes were absorbed into the Korean society that had kept traditional costumes.

A Study on Particulate Matter Reduction Effects of Vegetation Bio-Filters by Airflow Volume (공조풍량별 식생바이오필터의 입자상 오염물질 저감효과 연구)

  • Choi, Boo Hun;Kim, Tae Han
    • Journal of the Semiconductor & Display Technology
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    • v.20 no.4
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    • pp.89-95
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    • 2021
  • As the influence of fine dust on society spreads gradually, the public's interest in indoor air is increasingly rising. Air-purifying plants are drawing keen attention due to their natural purifying function enabled by plant physiology. However, as their fine dust reduction mechanism is limited to adsorption only, vegetation bio-filters that optimize purification effects through integration with air-conditioning systems is rising as an alternative. In accordance with the relevant standard test methods, this study looked into the fine dust reduction assessment method by air-conditioning airflow volume that can be used for the industrial spread of vegetation bio-filters. In the case of PM10 at 300 ㎍/m3, it was in the order of EG-B(3,500CMH, 29 min.) < EG-A (2,500CMH, 37 min.) < CG(0CMH, 64 min.) for reaching the maintenance level (100 ㎍/m3) of publicly used facilities. For reaching the WHO Guideline(50 ㎍/m3) requirement, it was in the order of EG-B (51 min.) < EG-A (160 min.) < CG (170 min.). In the case of PM2.5, it was in the order of EG-B (26 min.) < EG-A (33 min.) < CG (57 min.) for reaching the maintenance level (50 ㎍/m3) of publicly used facilities. It was in the order of EG-B (48 min) < EG-A (140 min) < CG (158 min) for reaching the WHO Guideline (25 ㎍/m3) requirement. The findings from the analysis showed that fine dust can be reduced most efficiently when the system is operated at 3,500CMH level. The limitation of this study is that due to the absence of a way of assessing the stress of plants in vegetation bio-filters, generating optimal air-conditioning air flow of the relevant system and economics analysis against the existing facility-type air purification system have been clarified, which should be explored further though follow-up studies.

CARE OF TRISMUS AND OROCUTANEOUS FISTULA BY ODONTOGENIC INFECTION IN A DISABLED PATIENT (장애환자에서 치성감염에 의한 아관긴급과 구강피부누공의 관리)

  • Oh, Ji-Hyeon;Son, Jeong-Seog;Yoo, Jae-Ha;Kim, Jong-Bae
    • The Journal of Korea Assosiation for Disability and Oral Health
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    • v.9 no.2
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    • pp.111-117
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    • 2013
  • Some odontogenic infections erode into fascial spaces directly and spread toward lymphatic tissues and blood streams. The principal maxillary primary spaces are the canine, buccal, and infratemporal space, the next secondary spaces are the masseteric, temporal and pharygeal space. As a result of the infection, trismus and orocutaneous fistula may be occurred. Trismus is owing to conditions not associated with temporomandibular joint itself and may be of myogenic, neurogenic, or psychogenic nature. Muscular trismus is due to infection adjacent to the elevator muscles of the jaw. The four principles of treatment of infection are as follows: (1) removal of the cause, (2) establishment of drainage, (3) institution of antibiotic therapy, and (4) provision of supportive care, including rest, nutrition and physiotherapy. Jaw physiotherapy is necessary to increase the amount of mouth opening and regain normal muscle tone. If proper care of odontogenic infection could be attained, the orocutaneous fistula will heal and close spontaneously by wound contraction mechanism of natural homeostatic response. This is a case report of the care of trismus and orocutaneous fistula due to fascial space abscess by advanced odontogenic infection in a physically disabled patient.