• Title/Summary/Keyword: 미분무

Search Result 84, Processing Time 0.033 seconds

A study on the Fire Extinguishing performance test of Water-Based Fire Protection System on Wooden cultural property (목조문화재에 대한 수계소화설비의 소화성능 실험 연구)

  • Kim, Hyun-Ju;Roh, Sam-Kew;Ham, Eun-Gu;Kim, Dong-Cheol;Kim, Kyung-Sik
    • Proceedings of the Korea Institute of Fire Science and Engineering Conference
    • /
    • 2011.11a
    • /
    • pp.179-182
    • /
    • 2011
  • 본 연구는 목조 건축물의 규모(높이)에 따른 수계 소화설비의 화재 진압 성능을 비교하여 최적의 소화설비를 선택함을 목적으로 한다. 높이 2.5m(소), 4m(중), 5.5m(대)의 모형화재실을 제작하고 모형화재실 천장에 스프링클러헤드와 미분무헤드를 설치, 소화실험을 진행하여 천장부 온도변화 및 소화시간, 방수량을 측정한다.

  • PDF

Explicit and Implicit Dynamic Analysis Using MLS Difference scheme (이동최소제곱 차분법을 이용한 explicit 및 implicit 2차원 동적해석)

  • Kim, Kyeong-Hwan;Lee, Sang-Ho;Yoon, Young-Cheol
    • Proceedings of the Computational Structural Engineering Institute Conference
    • /
    • 2011.04a
    • /
    • pp.719-722
    • /
    • 2011
  • 본 연구에서는 이동최소제곱 차분법을 2차원 동적고체문제를 해석하기 위하여 확장시켰으며 Newmark ${\beta}$ 방법을 통해 explicit와 implicit 시간적분법을 모두 적용하여 그 차이를 비교하였다. 이동최소제곱 차분법은 Taylor 다항식을 이용하여 미분계산을 근사화 함으로써 내부 및 경계에서도 강형식을 그대로 이용할 수 있다. 그래서 계산이 빠르고 수치적분이 필요하지 않아 무요소법의 장점을 잘 살릴 수 있고 해석차수를 손쉽게 조정할 수 있어 cubic 등의 고차 근사계산이 간편하다. 두 가지 수치예제를 통하여 동적해석에 대한 이동최소제곱 차분법의 적용성과 안정성을 검증하였다.

  • PDF

Fluidity and Compressive Strength Properties of Cement-Mortar admixed with II-Anhydrite and Pozollanic Fine Powders (불산부생 II -형 무수석고와 포졸란 미분체가 혼입된 시멘트.몰탈 유동성 및 압축강도 특성)

  • 김도수;김재호;조민형;전진환;남재현;노재성
    • Proceedings of the Korea Concrete Institute Conference
    • /
    • 1996.10a
    • /
    • pp.154-165
    • /
    • 1996
  • As II-anhydrite reacts with C3A(aluminate), C4AF(ferrite) at initial hydration of cement and assists the hydrolysis of C3S(calcium silicate), the production rate of ettringite(3C3A.3CaSO4.32H2O) and C-S-H gel was acclerated. It was known that compressive strength of cement concrete improved due to the effect of II-anhydrite. For the checking these effects of II-anhydrite, the fluidity and compressive strength of cementmortar admixed with II-anhydrite and pozollanic fine powders were investigated. By means of SEM analysis, the surface structure of mortar with the condition of steam curing at curing days=28 was investigated. As a result of this experiment, it was examined that II-anhydrite had an increase on the fluidity of cementpaste and compressive strength of mortar.

  • PDF

A Study on Properties of the High-Strength Concrete Admixed with II-Anhydrite and Pozzolanic Fine Power (불산부생 II 형 무수석고와 포졸란 미분체가 혼입된 고강도콘크리트의 특성에 관한 연구)

  • 조민형;길배수;전진환;김도수;남재현;노재성
    • Proceedings of the Korea Concrete Institute Conference
    • /
    • 1997.04a
    • /
    • pp.136-145
    • /
    • 1997
  • The purpose of this study is to develope of alternative adimixture for manufacture of PHC pile(compressive strength above 800kg/$\textrm{cm}^2$). For the investigation, properties of alternative admixture admixed with II-anhydrite and pozollanic fine powders(e.q., Fly-ash, Silica-Fume), the fluidity and viscosity in the cement pastes, the fluidity and compressive strength in mortars at steam curing condition, were respectively examined. Also, properties of compressive strength of concretes with exiting admixture(specimen name SM) and alterantive admixture(specimen name AP) for PHC pile, at steam and standard curing condition, were compared each other. As a result of this experimental study, it was found that specimens admixed with II-anhydrite and pozollanic fine powders had an increase on the fluidity of cement paste and mortar, and compressive strength of mortar and concrete was as good as concrete with SM.

  • PDF

A Study on the Production of Orthophoto Map from Digital Imagery Data of SPOT Satellite (SPOT 위성의 수치영상자료를 이용한 정사투영사진지도의 제작에 관한 연구)

  • Yeu, Bock-Mo;Sohn, Duk-Jae;Park, Joung-Nam;Jeong, Soo
    • Journal of Korean Society for Geospatial Information Science
    • /
    • v.1 no.2 s.2
    • /
    • pp.83-96
    • /
    • 1993
  • The orthophto map is seen as the form of picture with the uniform reduced scale as the current terrain map. Thus it provides a reasonable feeling of scene and is easy to be interpreted. Furthermore, digital orthophoto is currently used as the basic terrain information data of the Geo-Spatial Information System(GSIS). Therefore, the orhtophoto map has high potential use as a future terrain map. This paper studies the method of producing orthophoto map by using the digital satellite imagery data taken from SPOT satellite of France. The production of orthophoto map requires the process of generating orthophoto imagery with digital elevation model, which process is called digital differential rectification. As the final accuracy of orthophoto map depends on that of digital elevation model, the precise and efficient production method of digital elevation model should be preceded. This study investigated the method of producing digital elevation model directly from SPOT satellite imagery and generated ortho-image by resampling the original SPOT imagery through digital differential rectification. Finally, Simple orthophoto map was made by overlaying the ortho-image and the contour map from digital elevation model.

  • PDF

Quality Properties of Zero Cement Blast Furnace Slag Mortar Using the Recycled Fine Aggregates Depending on Mixing Factors (순환잔골재를 사용한 무 시멘트 고로슬래그 모르터의 배합요인에 따른 품질특성)

  • Han, Cheon-Goo;Son, Seok-Heon;Park, Kyung-Taek
    • Journal of the Korean Recycled Construction Resources Institute
    • /
    • v.5 no.3
    • /
    • pp.70-77
    • /
    • 2010
  • This study is to investigate experimentally the influence of mixing factors, such as a mortar mix proportion of non-cement mortar, flow, and W/B, on quality characteristics of blast furnace slag powder mortar incorporating dry type recycled fine aggregates. In the characteristics of fresh mortar, the W/B increased according to the increase in the flow due to the increase in water contents, but air contents decreased due to loss of air contrary to the increase in the W/B. In the case of hardened mortar, the compressive strength showed a decrease due to the highly determined W/B inversely according to the increase in the flow through the entire age in which the compressive strength increased proportionally according to the increase in the B/W. Also, the increasing rate of such compressive strength increased more largely due to the latent hydraulic property of the BS according to the passage of the age. The flexural strength at the age of 28 days according to the increase in the B/W represented a similar level in strength values without any increases. The flexural strength for the compressive strength was distributed as a range of 1/2 ~ 1/3 and that showed a higher range than that of conventional concretes.

  • PDF

Texture Properties of a Korean Rice Cake (Karedduk) with Addition of Carbohydrate Materials (당류 물질 첨가 가래떡의 텍스처 특성)

  • Kim, Sang-Sook;Chung, Hae-Young
    • Journal of the Korean Society of Food Science and Nutrition
    • /
    • v.36 no.9
    • /
    • pp.1205-1210
    • /
    • 2007
  • Texture properties of a Korean rice cake (Karedduk) added with carbohydrate materials after 0, 2, 6, 24 and 30 hrs of storage at $5^{\circ}C$ were investigated using textural characteristics and sensory descriptive analysis. Carbohydrate materials such as powdered sugar, trehalose, fructooligosaccharide (95%), isomalto, healtholigo, and galactooligosaccharide (50%) were added in 0, 1, 5 and 10% levels to dry rice flour. The texture profile analysis by Texture Analyzer revealed that adhesiveness and cohesiveness of the Korean rice cake (Karedduk) added with carbohydrate materials were similar to those of the control in trends, while hardness was low compared to the control except for fructooligosaccharide (95%) 5% and healtholigo 1% addition. The hardness and sweetness by sensory characteristics were significantly different compared to the control. Instrumental hardness was correlated with sensory hardness. Lastly, the Korean rice cake (Karedduk) added with carbohydrate materials except fructooligosaccharide (95%) 5% and healtholigo 1% addition was effective in delaying retrogradation.

Strength Development of Fly ash Substituted Concrete due to Blast Furnace Slag Powder and Gypsum Addition (고로슬래그 미분말 및 석고혼입에 따른 플라이애시 치환 콘크리트의 강도발현 특성)

  • Han, Cheon-Goo;Han, Min-Cheol;Jeon, Kyu-Nam
    • Journal of the Korean Recycled Construction Resources Institute
    • /
    • v.5 no.2
    • /
    • pp.97-104
    • /
    • 2010
  • In this study, the effect of blast furnace slag and gypsum addition on strength development of fly ash substituted concrete is investigated experimentally. As a result, the fluidity represented a similar or larger level than that of OPC but showed a tendency to decrease the fluidity according to the increase in the replacement level of BS and GS for the FA replacement concrete. In the case of the air content, although it showed a larger decrease compared to that of OPC, it also represented that BS and GS did not affect the air content significantly. Regarding the compressive strength in the case of the replacement of BS and GS for the FA 10% replacement concrete, it showed a higher early strength than OPC. Whereas, in the case of the BS 5% replacement and GS 1% incorporation for the FA 10% replacement concrete showed the most excellent performance due to its high strength. In the correlation of the compressive strength according to the kinds of admixtures, it was evident that the GS incorporation played an important role in high strength gain.

  • PDF

Evaluation Model and Experimental Validation of Tritium in Agricultural Plant (농작물의 삼중수소 오염평가 모델 개발 및 실험검증)

  • Kang Hee Suk;Keum Dong-kwon;Lee Hansoo;In Jun;Choi Yong Ho;Lee Chang Woo
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
    • /
    • v.3 no.4
    • /
    • pp.319-328
    • /
    • 2005
  • This paper describes a compartment dynamic model for evaluating the contamination level of kritium in agricultural plants exposed by accidentally released tritium. The present model uses a time-dependent growth equation of plant so that it can predict the effect of growth stage of plant during the exposure time. The model including atmosphere, soil and plant compartments is described by a set of nonlinear ordinary differential equations, and is able to predict time-dependent concentrations of tritium in the compartments. To validate the model, a series of exposure experiments of HTO vapor on Chinese cabbage and radish was carried out at the different growth stage of each plant. At the end of exposure, the tissue free water(TFWT) and the organically bound tritium(OBT) were measured. The measured concentrations were agreed well with model predictions.

  • PDF

Biological Activities of Culture Broth of Some Wood Rotting Basidiomycetes -Antimicrobial, plant growth regulatory, antitumor, and enzymatic activities- (목재부후성 담자균류 배양균사체의 생물활성 연구 -항균활성, 식물생장조절활성, 항암활성, 효소활성탐색-)

  • Cho, Soo-Muk;Yu, Seung-Hun;Shin, Gwan-Chull
    • The Korean Journal of Mycology
    • /
    • v.24 no.1 s.76
    • /
    • pp.17-24
    • /
    • 1996
  • For screening of biological activities of culture broth of some wood rotting basidiomycetes, antimicrobial activity, plant growth regulating activity, antitumor activity, and various enzyme activities were checked. Coriolus versicolor 5129 and C. pubescens 5131 strains showed inhibition activity against gram-positive bacteria and Lenzites betulina 8029 strain showed the activity against gram-negative bacteria. L. betulina 8085 inhibited the growth of both bacteria and plant pathogenic fungi. All of tested basidiomycetes inhibited the germination and growth of radish and cabbage at concentration of 0.8ml/ml. Especially, Fomitopsis pinicolor 8059 and Fomitella fraxinea 8084 showed strong inhibition activity. In contrast, Bjerkandera adusta 8054 stimulated the growth of cabbage and radish at concentration of 0.4 and 0.2ml/ml. All polysaccharides from tested basidiomycetes showed anti-tumor activity against sarcoma 180 and the stronger antitumor activity was observed in L. betulina 8029 and unidentified 8058 strain. All tested basidiomycetes had also an ability to degrade cellulose and lignin.

  • PDF