• Title/Summary/Keyword: AMF

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Development of Accident Modification Factors for Road Design Safety Evaluation Algorithm of Rural Intersections (지방부 교차로의 도로설계 안전성 판단 알고리즘 구축을 위한 AMF 개발 (신호교차로를 중심으로))

  • Kim, Eung-Cheol;Lee, Dong-Min;Choe, Eun-Jin;Kim, Do-Hun
    • Journal of Korean Society of Transportation
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    • v.27 no.3
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    • pp.91-102
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    • 2009
  • A traffic accident prediction model developed using various design variables(road design variables, geometric variables, and traffic environmental variables) is one of the most important factors to safety design evaluation system for roads. However, statistical accident models have a crucial problem not applicable for all intersections. To make up this problem, this study developed AMFs(Accident Modification Factors) through statistical modeling methods, historical accident databases, judgment from traffic experts, and literature review by considering design variable's characteristics, traffic accident rates, and traffic accident frequency. AMFs developed in this study include exclusive left-turn lane, exclusive right-turn lane, sight distance, and intersection angle. Predictabilities of the developed AMFs and the existing accident prediction models are compared with real accident historical data. The results showed that performances of the developed AMFs are superior to the existing statistical accident prediction models. These findings show that AMFs should be considered as a important process to develop safety design evaluation algorithms. Additionally, AMFs could be used as an index that can judge the impact of corresponding design variables on accidents in rural intersections.

Spore Diversity of Arbuscular Mycorrhizal Fungi in a Post-mining Area in Korea (폐광산 지역의 근권 토양에 분포하는 수지상균근균 포자의 다양성)

  • Park, Hyeok;Lee, Eun-Hwa;Ka, Kang-Hyeon;Eom, Ahn-Heum
    • The Korean Journal of Mycology
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    • v.44 no.2
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    • pp.82-86
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    • 2016
  • In this study, we investigated the spore diversity of arbuscular mycorrhizal fungi (AMF) in rhizospheres of a post-mining area and a natural forest area in Jecheon, Korea. The rhizospheres of the post-mining areas were dominated by Acaulospora mellea, while those of the natural forest area were dominated by Ambispora leptoticha. The number of AMF spores in rhizospheres of the post-mining area was significantly higher than that in the rhizospheres of the natural forest area. Although the diversity index of each area showed no significant difference, the community similarity of AMF within the rhizospheres of natural forest area was significantly higher than that observed within those of post-mining area. These results showed that AM fungal communities in rhizospheres could change because of the degree of disturbance.

Effects of Arbuscular Mycorrhizal Fungus, Glomus manihot, on Plant Growth and Nutrient Uptake of Pepper Seedlings (Arbuscular mycorrhizal fungus인 Glomus manihot 균 접종이 고추의 성장과 영양분 흡수에 미치는 영향)

  • 이호용;민봉희
    • Korean Journal of Environmental Biology
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    • v.21 no.3
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    • pp.292-296
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    • 2003
  • Effects of aybusculayr mycorrhizal fungus (aMF), Glomus manihot, on plant growth and nutrient uptake on pepper (Capsicum annuum L.) seedlings were evaluated in the nursery experiment. Five different strains of pepper, Chungok, Shingang, Manitta, Gonggongchil, and Shintaeyang, were used in this study. Total fresh weight, nutrient (nitrogen, phosphate and potassium) uptake were increased in all strains inoculated with G. manihot alone and G. manihot and rock phosphate over control at 2 weeks after seeding. Plant weight and phosphate uptake in plants treated with AMF were significantly higher (P< 0.05) than those of control at 6 weeks after seeding. The treatment with G. manihot and rock phosphate gave better plant performance than the treatment with G. manihot alone at 6 weeks after seeding. The lengths of pathogenic symptom on pepper by Phytophthora capsici were reduced significantly by the inoculation of G. manihot spores, Therefore, it would be expected that AMF can be used as the biocontrol agent on pathogens in pepper.

Effect of Arbuscular Mycorrhizal Fungi on Growth of Korean Ginseng (Panax ginseng C. A. Mey.) Seedlings (수지상균근균이 인삼 (Panax ginseng C. A. Mey.)의 생장에 미치는 영향)

  • Kil, Yi-Jong;Eo, Ju-Kyeong;Eom, Ahn-Heum
    • The Korean Journal of Mycology
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    • v.41 no.2
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    • pp.81-94
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    • 2013
  • The purpose of this study was to investigate effects of inoculation of arbuscular mycorrhizal fungi (AMF) on growth of Korean ginseng (Panax ginseng C. A. Mey.) seedlings. Five species of AMF (Glomus mosseae, Glomus intraradices, Glomus etunicatum, Acaulospora longula, Acaulospora trappei) were inoculated to ginseng seedlings at 60 days after ginseng seed germination. Dry weights, heights of the plants and chlorophyll fluorescence were measured at 120 days after inoculation of AMF. Dry weights and shoot heights were increased in seedlings inoculated with AMF compared to the controls without AMF. However, chlorophyll fluorescence of seedlings with AMF showed no significant difference compared to the control.

Diversities of Arbuscular Mycorrhizal Fungi in Cultivated Field Soils of Korean Ginseng (금산의 인삼 재배 토양에 분포하는 수지상균근균의 다양성)

  • Kil, Yi-Jong;Eo, Ju-Kyeong;Eom, Ahn-Heum
    • The Korean Journal of Mycology
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    • v.40 no.1
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    • pp.1-6
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    • 2012
  • In this study, soil samples were collected from cultivated fields of 1-5 year old Korean ginseng in Geumsan, Korea. Spores of arbuscular mycorrhizal fungi were extracted from soils and identified using morphological characteristics and 18s rDNA sequences of the spores. Total 10 species of AMF were identified: Acaulospora longula, Archaeospora trappei, Glomus caledonium, Glomus etunicatum, Glomus intraradices, Glomus mosseae, Glomus sp., Paraglomus occultum, Paraglomus brasilianum, and Scutellospora heterogama. Relative abundance of spores of A. trappei were increased with increase of cultivation period of the ginseng. However, relative abundance of other species of AMF and Shannon diversity (H') of AMF were significantly decreased with the increase of cultivation periods of the ginseng.

Radioprotective role of amifostine on osteointegration of titanium implants in the tibia of rats

  • Nevra Aydemir Celep;Hulya Kara ;Elif Erbas;Elif Dogan
    • Journal of Veterinary Science
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    • v.24 no.3
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    • pp.35.1-35.10
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    • 2023
  • Background: Titanium is the most widely used metal for bone integration, especially for cancer patients receiving ionizing radiation. This study aimed to investigate the amifostine administration that would reduce the effects of radiation on bone healing and osseointegration in rat models. Objectives: It is aimed that the application of amifostine in rats receiving radiotherapy treatment will reduce the negative effects of ionizing radiation on the bone. Methods: Thirty-five adult male Wistar rats were randomly divided into one healthy and four experimental groups. In three consecutive days, two experimental groups of rats (AMF-RT-IMP and RT-IMP) were exposed to radiation (15 Gy/3 fractions of 5 Gy each). Then the titanium implants were inserted into the left tibia. Before the radiotherapy process, a 200 mg/kg dose of amifostine (AMF) was administered to the rats in the AMF-IMP and AMF-RT-IMP groups. Twenty-eight days after the screw implant, all rats were sacrificed, and their blood samples and tibia bones were collected for analysis. Results: The results indicated an accelerated bone formation and a more rapid healing process in the screw implants in the AMF-IMP, AMF-RT-IMP, and AMF-RT groups than in the RT-IMP group. Also, bone-implant contact area measurement and inflammation decreased with amifostine treatment in the implants subjected to irradiation (p < 0.05). Conclusions: The results obtained in the present study suggested that amifostine prevents the losses of bone minerals, bone integrity, and implant position from ionizing-radiation when given before exposure.

Comparison of AMF Contacts for High Interrupting Capacity Vacuum Interrupter (고차단용량 진공인터럽터의 AMF 전극 비교연구)

  • Kim, J.S.;Choi, M.J.;Ryu, S.S.;Kim, I.M.;Choi, Y.C.
    • Proceedings of the KIEE Conference
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    • 2004.07c
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    • pp.1863-1865
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    • 2004
  • As rise the demands for the protcetion of environment and the compactness of equipments, the movement brisks for replacing the circuit breaker of GIS(Gas Insulated Switchgear) to VI(Vacuum Interrupter). For these reason an increase in the interruption capability of VI is required. To satisfy these requirement, the academic and industrial worlds have been studying extensively for AMF(Axial Magnetic Field) contact, which is effective in interrupting large current over tens of kA, and introduced many kind of AMF contacts. However there are little effort to compare these contacts comprehensively, so it is difficult to choose most suitable shape for user's needs. In this paper, focusing unipolar type contact among various type of AMF contacts, we performed magnetic field analysis for several models designed in same dimension and compared the result and characteristics of each model in order to help deciding the direction for developing profitable VIs for interrupting large current.

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Symbiotic Properties of Arbuscular Mycorrhizal Fungi and Sand Dune Plants (사구식물(砂丘植物)과 Arbuscular 내생균근(內生菌根) 균(菌)의 공생(共生) 특성(特性))

  • Kim, Jun-Tae;Lee, Ki-Hyeon;Jung, Byung-Chul;Kim, Chong-Kyun
    • The Korean Journal of Mycology
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    • v.21 no.3
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    • pp.235-245
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    • 1993
  • The symbiotic properties of arbuscular mycorrhizal fungi(AMF) such as the absence and/or presence of symbiosis, spore density, and six factors of phycochemical properties of soil were investigated in the rhizosphere of seven sand dune plants and three control plants around Kum river. The infection of AMF was confirmed in all plants. Three genera, nine species of the AMF spores were identified in the sand dune; Ac. scrobiculata, G. aggregatum, G. convolutum, G. diaphanum, G. dimophicum, G. geosporum, G. vesiculiferum, G. tortuosum, S. pachycaulis. All of them were also found in the control, but S. pachycaulis were only separated in the sand dune. In the control, three genera, four species were identified; G. flavisporum, Gi. margarita, Sc. gregaria. Sc. persica. The species specificity was not found between the sand dune plant and AMF. However, the AMF was thought to be correlated with the soil factors. The spore density was stimulated with increase of the organic matter and the nitrogen content, but inhibited with the water content and the phosphorus content. In respect of the seasonal factor, the spore density was increased in the late growth period of plants.

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Effects of Alternating Magnetic Field Assisted Annealing of Pentacene Film for Organic Thin Film Transistor Applications

  • Park, Jae-Hoon;Choi, Jong-Sun
    • Transactions on Electrical and Electronic Materials
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    • v.8 no.1
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    • pp.32-35
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    • 2007
  • In this article, a novel annealing technique using alternating magnetic field (AMF) is adopted to improve the electrical characteristics of pentacene film, thereby enhancing the performance of pentacene-based organic thin film transistors (OTFTs). According to the investigation results, the electrical conductivity in the pentacene film could be increased from 0.32 to 1.18 S/cm by annealing the pentacene film using AMF. And also, OTFTs with the pentacene film annealed by AMF exhibited an improved performance compared to the device without annealing. These results suggest that an annealing using AMF can be an effective method to improve the performance of devices based on organic semiconductors.

Effects of Organic Farming on Communities of Arbuscular Mycorrhizal Fungi

  • Lee, Si-Woo;Lee, Eun-Hwa;Eom, Ahn-Heum
    • Mycobiology
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    • v.36 no.1
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    • pp.19-23
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    • 2008
  • Red pepper (Capsicum annum L.) roots and soils representing different agricultural management practices such as conventional (CON), no-chemical (NOC), and organic farming systems (ORG) were collected from 32 farm field sites in Kyunggi, Korea to investigate the effects of these agricultural practices on arbuscular mycorrhizal (AM) symbiosis. ORG inoculum significantly increased plant growth compared to inoculum from CON and NOC. A community analysis of AM fungi (AMF) using morphological features of spores revealed that AMF spore abundance and species diversity were significantly higher in ORG than in CON. Additionally, a community analysis of AMF colonizing roots using a molecular technique revealed higher AMF diversity in ORG than in CON. These results suggest that agricultural practices significantly influence AM fungal community structure and mycorrhizal inoculum potential.