• Title/Summary/Keyword: growth fire

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A Research on the Renovation Situation of the Business Buildings (업무시설의 리노베이션 현황에 관한 조사 연구)

  • Lee, Hyun-Jeong;Shim, Myung-Sup
    • Journal of the Korea Institute of Building Construction
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    • v.2 no.2
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    • pp.121-127
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    • 2002
  • The functions and uses of existing buildings are not properly changing as modern life needs. As a result, the frequent reconstruction(construction after removal) of existing buildings have been done but it became more and more difficult because of strengthening of regulations and systems concerning construction. And also it has several disadvantages like lower plot ratio and site coverage than existed buildings, enormous construction cost, production of waste-construction materials and thoughtless consumption of natural resources, which gives rise to environmental pollution. Therefore renovation is brought to the fore. In Korea, many business buildings were constructed in 1960s-1970s, during the period of high growth. Such buildings needs to be repaired in whole. It is caused by the change of social, economic, and cultural conditions and deterioration of equipments. Therefore renovation meets some necessary conditions; recovery of building functions and extension of building life span. In case study, the present state of renovation in business buildings is 1) Basic safety, for example, fire prevention and crime prevention, is great important. 2) Advanced technology, INS(international news service), IBS(Intelligent Building System), and internationalization, is pursued for adapting to multimedia ages. 3) It tries to promote proficiency, and to save the energy using spatial environment and natural energy(light and sound). Also, improving comfortable level of users and installing equipments for physically handicapped person needs to be considered.

A Study on the Characteristics of Short Circuit through the Cross Section Analysis of Electric Wire (전선의 단면분석을 통한 단락특성에 관한 연구)

  • Shong, Kil-Mok;Choi, Chung-Seog;Kim, Yun-Hoi;Kim, Sang-Hyeon;Park, Nam-Kyu
    • Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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    • 2005.05a
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    • pp.51-56
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    • 2005
  • For a fire cause judgement this paper describes the short circuit characteristics of a electric wire through the cross section analysis under ac condition. The cower wires prepared for the experiment were 1.2mm, 1.6mm, and 2.0mm in diameter. Through the cross section analysis(CSA), it was confirmed that the dendrite structure grew at the angle of about $40^{\circ}\;or\;60^{\circ}$ when the fusing current was applied to the wires. The larger the fusing current is, the more decreased the growth angle of the dendrite structure is. It was confirmed that the dendrite structure was arranged like the columnar structure. In this paper, the characteristics analysis of short circuit was carried out in the range of transient duration and the correlation constant k was investigated by measuring the short circuit duration and the fusing current.

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The Mongolian LTER : Hovsgol National Park

  • Goulden;Clyde E.;J. Tsogtbaatar;Chuluunkhuyag;W.C. Hession;D. Tumurbaatar;Ch. Dugarjav;C. Cianfrani;P. Brusilovskiy;G. Namkgaijangtsen
    • The Korean Journal of Ecology
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    • v.23 no.2
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    • pp.135-140
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    • 2000
  • The Government of Mongolia approved establishment of the Mongolian LTER network in December 1997. In June 1998, a seminar was organized by the Mongolian Academy of Sciences to initiate the program. Dr. James Gosz of the US LTER program keynoted the seminar. A Mongolian LTER Steering Committee was established to organize the network and to develop guidelines for its management. This Committee designated Hovsgol National Park in northern Mongolia as the first Mongolian LTER network site. Other potential sites are presently being considered. including study sites in steppe grassland and desert locations. The primary goals of the Mongolian LTER Network are to study human impacts on Mongolia's environment; with a focus on short-term impacts of nomadic grazing on terrestrial and aquatic ecosystems and long-term climate change impacts on more pristine environments in the protected areas. There are at least two additional goals: to provide information and advice on how best to protect Mongolia's pristine environments, and to train Mongolian students to work on environmental problems to encourage the growth of expertise for making sound environmental decisions.

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WSR Study of Particle Size, Concentration and Chemistry Near Soot Inception (WSR 초기매연 조건에서의 입자 크기, 농도 및 화학적 특성)

  • Lee, Eui-Ju;Mulholland, George W.
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.28 no.9
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    • pp.1117-1123
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    • 2004
  • The characteristics of soot near the soot inception point for an ethene-air flame was carried out in a WSR (well-stirred reactor). The new sampling tool like the temperature controlled filter system was introduced to minimize the condensation during sampling. The new analysis tools applied include the real time size distribution analysis with the Nano-DMA, particle size by transmission electron microscopy, C/H analysis, g filter analysis, and thermogravimetric analysis using both non-oxidative and oxidative pyrolysis. The WSR can generate young soot particles that can be collected and examined to gain insight into inception. For the current conditions, soot does not form for ${\Phi}$=1.9, inception occurs at or before ${\Phi}$=2.0, and inception combined with soot surface growth and/or coagulation occurs for ${\Phi}$=2.1. The filter samples for ${\Phi}$=1.9 are composed of volatile compounds that evolve at relatively low temperatures when heated in the presence or absence of O$_2$. The samples collected from the WSR at ${\Phi}$=2.0 and ${\Phi}$=2.1 are precursor-like in morphology and size. They have higher C/H ratios and lower organic percentages than precursor particles, but they are clearly not fully carbonized soot. The WSR PAH distribution is similar to that in young soot from inverse flames.

Preparation of Novel Magnesium Precursors and MgO Thin Films Growth by Atomic Layer Deposition (ALD)

  • Kim, Hyo-Suk;park, Bo Keun;Kim, Chang Gyoun;Son, Seung Uk;Chung, Taek-Mo
    • Proceedings of the Korean Vacuum Society Conference
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    • 2014.02a
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    • pp.364.2-364.2
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    • 2014
  • Magnesium oxide (MgO) thin films have attracted great scientific and technological interest in recent decades. Because of its distinguished properties such as a wide band gap (7.2 eV), a low dielectric constant (9.8), a low refractive index, an excellent chemical, and thermal stability (melting point=$2900^{\circ}C$), it is widely used as inorganic material in diverse areas such as fire resistant construction materials, optical materials, protective layers in plasma display panels, buffer layers of multilayer electronic/photonic devices, and perovskite ferroelectric thin films. Precursor used in the ALD requires volatility, stability, and low deposition temperature. Precursors using a heteroleptic ligands with different reactivity have advantage of selective reaction of the heteroleptic ligands on substrate during ALD process. In this study, we have synethesized new heteroleptic magnesium precursors ${\beta}$-diketonate and aminoalkoxide which have been widely used for the development of precursor because of the excellent volatility, chelating effects by increasing the coordination number of the metal, and advantages to synthesize a single precursor. A newly-synthesized Mg(II) precursor was adopted for growing MgO thin films using ALD.

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Modulation of Bacteria with a Combination of Natural Products in KIMCHI Fermentation

  • Kim, Jong-Deog;Shin, Jin-Hyuk;Seo, Hyo-Jin;Lim, Dong-Jung;Hong, Soon-Kang;Shin, Tai-Sun
    • KSBB Journal
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    • v.23 no.2
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    • pp.118-124
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    • 2008
  • Three kinds of bacteria that influence Kimchi fermentation, Lactobacillus plantarium for acidity, Leuconostoc mesenteroides for ripening Kimchi, and Pichia membranifaciens for decreasing Kimchi quality, were regulated by natural products including Theae folium, Taraxacum coreanum, Brassica juncea, Astragali radix, Gynostemma pentaphyllum, Camellia japonica, Agaricus blazei, and Cordyceps militaris. The common prescription combined T. folium, T. coreanum and C. militaris and simultaneously regulated these 3 bacteria as follows: the growth of L. plantarium and P. membranifaciens were inhibited and L. mesenteroides was promoted. The most effective mixing ratio was T. folium: T. coreanum: C. militaris = 3:2:1. With this new prescription, deep flavor, extended preservation, and a special taste are expected in the Kimchi due to these natural products.

Black Locust (Robinia pseudoacacia L.) in Bulgaria

  • Iliev, Nasko;Iliev, Ivan;Park, Young-Goo
    • Journal of Korean Society of Forest Science
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    • v.94 no.5 s.162
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    • pp.291-301
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    • 2005
  • Robinia pseudoacacia is one of most widely cultivated exotic species in Bulgaria. The total area of black locust plantations amounts to 2.9% of the total forest area of the country. 15.34% of the plantations are of management afforestations category, where the priority is given to timber production. They have been created on rich and moisture soils, which are the most appropriate for the species in order to achieve its biological potentials of high productivity. The rest of the available plantations in the country are planted on poorer and drier soils up to 600~800 m altitude. The high adaptive ability of the species to unsuitable environmental conditions as well as the high sprout potential was used for their creation. These stands are mainly done with the aim to protect and ameliorate damaged environments and production of small-size timber and fire woods. They are cultivated until 15-20 years and are revived by sprouts. Therefore the management goals searched, 45.69% of those forests are low productive and 38.97% with average productiveness. The present report deals with growth and productivity capacity of black locust plantations; production of sowing materials; production of reproductive and vegetative saplings for afforestation; the technological aspects of afforestation works; the management and use of black locust plantations as well as some more important diseases and pests affecting the species. The report is entirely based on Bulgarian scientific research works and experience with the Robinia preudoacacia. Recommendations for optimizing the use of species are given.

Theobroxide Treatment Inhibits Wild Fire Disease Occurrence in Nicotiana benthamiana by the Overexpression of Defense-related Genes

  • Ahn, Soon Young;Baek, Kwang-Hyun;Moon, Yong Sun;Yun, Hae Keun
    • The Plant Pathology Journal
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    • v.29 no.1
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    • pp.110-115
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    • 2013
  • Theobroxide, a novel compound isolated from a fungus Lasiodiplodia theobromae, stimulates potato tuber formation and induces flowering of morning glory by initiating the jasmonic acid synthesis pathway. To elucidate the effect of theobroxide on pathogen resistance in plants, Nicotiana benthamiana plants treated with theobroxide were immediately infiltrated with Pseudomonas syringae pv. tabaci. Exogenous application of theobroxide inhibited development of lesion symptoms, and growth of the bacterial cells was significantly retarded. Semiquantitative RT-PCRs using the primers of 18 defense-related genes were performed to investigate the molecular mechanisms of resistance. Among the genes, the theobroxide treatment increased the expression of patho-genesis-related protein 1a (PR1a), pathogenesis-related protein 1b (PR1b), glutathione S-transferase (GST), allen oxide cyclase (AOC), and lipoxyganase (LOX). All these data strongly indicate that theobroxide treatment inhibits disease development by faster induction of defense responses, which can be possible by the induction of defense-related genes including PR1a, PR1b, and GST triggered by the elevated jasmonic acid.

The Optimal Design of Explosion Prevention for LPG Storage Tank (폭발방지를 고려한 LPG 저장탱크 최적설계)

  • Leem, Sa-Hwan;Huh, Yong-Jeong;Son, Seok-Woo;Lim, Jae-Ki
    • Proceedings of the KAIS Fall Conference
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    • 2010.05b
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    • pp.949-952
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    • 2010
  • The utilization of LPG(Liquefied Petroleum Gas) is increasing as an environmental-friendly fuel in all countries making green growth new paradigm, and use of gas is spread fast as motor fuels to decrease air pollution. Loss of lives by explosion and fire is happening every year as gas use increases, and gas accident in large scale storage property is causing serious problems socially. To minimize this problem, underground containment type storage tank is being presented as an alternative recently. In this study, to minimize explosion occurrence in underground containment type storage tank, the suitable storage tank is designed to consider explosion prevention that makes exposure surface area minimize in confined contents volume and flame to construct storage tank by the most suitable condition in the underground containment room. As a result of the design of storage tank having the most suitable condition by this research, underground containment space was minimized on diameter 3m, length 4.83m in 20 tons storage tank and its safety was improved as exposure surface area in flame decreased by 89.4%, compared with the existent storage tank.

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A Study on MgF$_2$/CeO$_2$ AR Coating of Mono-Crystalline Silicon Solar Cell (단결정 실리콘 태양전지의 MgF$_2$/CeO$_2$ 반사 방지막에 환한 연구)

  • 유진수;이재형;이준신
    • The Transactions of the Korean Institute of Electrical Engineers C
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    • v.52 no.10
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    • pp.447-450
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    • 2003
  • This paper presents a process optimization of antireflection (AR) coating on crystalline Si solar cells. Theoretical and experimental investigations were performed on a double-layer AR (DLAR) coating of MgF$_2$/CeO$_2$. We investigated CeO$_2$ films as an AR layer because they have a proper refractive index of 2.46 and demonstrate the same lattice constant as Si substrate. RF sputter grown CeO$_2$ film showed strong dependence on a deposition temperature. The CeO$_2$ deposited at 40$0^{\circ}C$ exhibited a strong (111) preferred orientation and the lowest surface roughness of 6.87 $\AA$. Refractive index of MgF$_2$ film was measured as 1.386 for the most of growth temperature. An optimized DLAR coating showed a reflectance as low as 2.04% in the wavelengths ranged from 0.4${\mu}{\textrm}{m}$ to 1.1${\mu}{\textrm}{m}$. We achieved the efficiencies of solar cells greater than 15% with 3.12% improvement with DLAR coatings. Further details on MgF$_2$, CeO$_2$ films, and cell fabrication parameters are presented in this paper.