• 화약ㆍ발파
• /
• 제8권1호
• /
• pp.3-16
• /
• 1990

The cautious blasting works had been used with emulsion explosion electric M/S delay caps. Drill depth was from 3m to 6m with Crawler Drill $\varphi{70mm}$ on the calcalious sand stone(sort-moderate-semi hard Rock). The total numbers of feet blast were 88. Scale distance were induces 15.52-60.32. It was applied to propagation Law in blasting vibration as follows. Propagtion Law in Blasting Vibration $V=K(\frac{D}{W^b})^n$ where V : Peak partical velocity(cm/sec) D : Distance between explosion and recording sites (m) W : Maximum Charge per delay-period of eighit milliseconds or more(Kg) K : Ground transmission constant, empirically determind on th Rocks, Explosive and drilling pattern ets. b : Charge exponents n : Reduced exponents Where the quantity $D/W^b$ is known as the Scale distance. Above equation is worked by the U.S Bureau of Mines to determine peak particle velocity. The propagation Law can be catagrorized in three graups. Cabic root Scaling charge per delay Square root Scaling of charge per delay Site-specific Scaling of charge per delay Charge and reduction exponents carried out by multiple regressional analysis. It's divided into under loom and over loom distance because the frequency is verified by the distance from blast site. Empirical equation of cautious blasting vibration is as follows. Over 30m----under l00m----- $V=41(D/3\sqrt{W})^{-1.41}$ -----A Over l00m-----$V= 121(D/3\sqrt{W})^{-1.66}$-----B K value on the above equation has to be more specified for furthur understang about the effect of explosives, Rock strength. And Drilling pattern on the vibration levels, it is necessary to carry out more tests.

• 화약ㆍ발파
• /
• 제9권4호
• /
• pp.3-12
• /
• 1991

The cautious blasting works had been used with emulsion explosion electric M /S delay caps. Drill depth was from 3m to 6m with Crawler Drill 70mm on the calcalious sand stone (soft-moderate-semi hard Rock) . The total numbers of feet blast were 88. Scale distance were induces 15.52-60.32. It was applied to Propagation Law in blasting vibration as follows .Propagtion Law in Blasting Vibration V=k(D/W/sup b/)/sup n/ where V : Peak partical velocity(cm/sec) D : Distance between explosion and recording sites(m) W ; Maximum Charge per delay -period of eight milliseconds or more(Kg) K : Ground transmission constant, empirically determind on the Rocks, Explosive and drilling pattern ets. b : Charge exponents n : Reduced exponents Where the quantity D/W/sup b/ is known as the Scale distance. Above equation is worked by the U.S Bureau of Mines to determine peak particle velocity. The propagation Law can be catagrorized in three groups. Cabic root Scaling charge per delay Square root Scaling of charge per delay Site-specific Scaling of charge delay Charge and reduction exponents carried out by multiple regressional analysis. It's divided into under loom and over loom distance because the frequency is varified by the distance from blast site. Empirical equation of cautious blasting vibration is as follows. Over 30m--under 100m----V=41(D/ W)/sup -1.41/-----A Over l00m---------V=121(D/ W)/sup -1.56/-----B K value on the above equation has to be more specified for furthur understand about the effect of explosives. Rock strength, And Drilling pattern on the vibration levels, it is necessary to carry out more tests.

• 한국콘크리트학회:학술대회논문집
• /
• 한국콘크리트학회 2004년도 추계 학술발표회 제16권2호
• /
• pp.751-754
• /
• 2004

There are many factors that affect on the flowing properties of high flowing concrete(HFC), which are fluidity, compactibility, non-segregation ability and fillingability. And because the aggregate which is one of the factors occupies high volume in concrete, it has a much effect on the properties of high flowing concrete according to its size, quality and quantity etc. This is an experimental study to analyze the effect of admixture and volume of coarse aggregate in concrete on the flowing properties of high flowing concrete. For this purpose, the kinds of admixture are fly-ash and blast furnace slag. Also volume of coarse aggregate in concrete are 280, 290, 300, 310, 320 $(\ell/m^3)$. The test of flowablity properties is slump-flow, Air content, V-lot, L-Flow. According to test results, it was found that the compactibility of HFC is more superior to use blast furnace slag than other, and according .to kind of admixture, most compatible volume of coarse are different. Also when used blast furnace slag, the volume of coarse are increased than used fly-ash.

• 콘크리트학회논문집
• /
• 제16권1호
• /
• pp.1-9
• /
• 2004

본 논문은 고로슬래그미분말을 혼화한 콘크리트의 염화물 침투 및 철관 발청 성능을 평가한 것이다. 실험에는 1종 보통포틀랜드시멘트와 5종 내황산염시멘트 사용하였으며, 고로슬래그는 이들 시멘트 대신에 각각 $25\%$, $40\%$ 및 $55\%$를 치환하였다. 촉진 염화물 침투 시험결과에 대한 평가는 ASTM C 1202에 규정에 따랐으며, 철근 발청은 건습반복에 의한 촉진 시험에 의해 수행되었다. 시험체는 콘크리트로 제작하였으며, 각각 수중양생 28일, 56일 및 91일간 실시하였다. 모든 콘크리트 시험체는 3일간 염수 침지한 후 4일간 건조로에서 건조시키는 것을 1 cycle로 정하여 30 cycle에서 시험을 종료하는 것으로 하였다. 염수 침지 조건은 수온 $40^{\circ}C$, NaCl $3^{\circ}C$로 하였으며, 시험체의 건조는 건조로를 사용하여 $60^{\circ}C$에서 건조시키는 것으로 하였다. 시험결과, 고로슬래그미분말을 혼화한 1종 시멘트를 사용한 콘크리트 시험체의 염소이온 확산계수는 무치환의 경우에 비해 상당히 감소하였으며, 5종 시멘트를 사용한 경우에 있어서는 1종 시멘트를 사용한 시험체에 비해 염소이온의 확산계수는 증가하는 것으로 나타났다. 촉진시험에 의한 철근 발청은 고로슬래그미분말의 사용에 의해 상당한 저항성을 갖고 있으며, 5종 시멘트를 사용한 경우에는 철근 발청이 증가하는 현상을 나타내었다.

• 천문학논총
• /
• 제12권1호
• /
• pp.173-183
• /
• 1997

We have numerically simulated the evolution of supernova remnant VRO 42.05.01(G166.0+43) in order to understand its morphology m radio and X-ray observations as well as the dynamical interaction of the supernova remnant with the surrounding interstellar medium. The Radio and ROSAT observations suggest that the unusual morphology of VRO 42.05.01 is caused by a supernova blast wave breaking out of the cloud boundary where the supernova event occurred, and expanding into another cloud across a much less dense and presumably hot cavity. Our numerical results are consistent with the interactions of a passing supernova blast wave with the clouds across the cavity. We discuss the implications of our results on the dynamics of VRO 42.05.01 such as the reverse shocks, the rejuvenation of the hot cavity, and the reflected shocks formed by the reverse shock collisions. We have theoretically mapped the radio continuum(1.4 GHz) and X-ray(0.1~2 keV) morphology which are consistent with the observational ones.

• 천문학회보
• /
• 제40권2호
• /
• pp.38.1-38.1
• /
• 2015

Supernova remnants (SNRs) are one of the most energetic astrophysical events and are thought to be the dominant source of Galactic cosmic rays (CRs). A recent report on observations of gamma rays from the vicinity of SNRs have shown strong evidence that Galactic CR protons are accelerated by the shock waves of the SNRs. The actual gamma-ray emission from pion decay should depend on the diffusion of CRs in the interstellar medium. In order to quantitatively analyze the diffusion of high-energy CRs from acceleration sites, we have performed test particle numerical simulations of CR protons using a three-dimensional magnetohydrodynamics (MHD) simulation of an interstellar medium swept-up by a blast wave. We analyse the CRs diffusion at a length scale of order a few pc, and show the Richtmeyer-Meshkov instability can provide enough turbulence downstream of the shock to make the diffusion coefficient close to the Bohm level for energy larger than 30 TeV for a realistic interstellar medium.

• 한국콘크리트학회:학술대회논문집
• /
• 한국콘크리트학회 2000년도 가을 학술발표회 논문집(II)
• /
• pp.1242-1247
• /
• 2000

Results from a study on the effect of the chemical agent on the flowing and setting properties of high flowing.high strength concrete using blast-furnace slag are presented in this paper. The flowing and setting properties of concrete are investigated by slump, slump-flow, flowing velocity, L-flow, velocity of V-funnel, L-spatial passability and setting time. In addition, kinds of chemical agent were composed of naphthalene type, of naphthalene and melamine and melamine type. The results indicate that dispersive capacity can be increased by naphthalene composition. Also, it shows that viscosity and early strength can be increased by melamine composition.

• 식물병연구
• /
• 제17권1호
• /
• pp.44-51
• /
• 2011

우리나라에서 주로 재배되는 가지과작물의 종자 전염 병원균 중에서 세균성 병원균 Xanthomonns campestris pv. vesicatoria(Xcv), Clavibacter michiganensis subsp. michiganensis (Cmm), Erwinia carotovora subsp. carotovora (Ecc)와 바이러스 병원균 Pepper mild mottle virus (PMMoV) and Tobacco mild green mosaic virus (TMGMV)를 종자로부터 동시검출하기 위한 One-step Multiplex RT-PCR을 개발하였다. 각각의 병원균을 특이적으로 증폭시키는 병원균 검출용 프라이머 15세트를 primer-blast 프로그램을 이용하여 제작하였고 각각의 병원균을 특이적으로 검출할 수 있는 5세트의 프라이머 세트(Cmm-F/R, Ecc-F/R, Xcv-F/R, PMMoV-F/R, TMGMVF/R)를 선발하였다. 이들 프라이머 세트는 프라이머간의 또는 병원균 cDNA간의 간섭없이 타겟 병원균만을 검출하였다. 가지과 작물 중에서 유통 중인 고추종자 20품종과 토마토종자 10품종에 대한 종자 감염 병원균 검출을 위한 PCR을 수행한 결과, 2개 품종의 토마토종자에서 Ecc가 검출되었고 4개 품종의 고추종자에서도 Ecc가 검출되었다. 특히 고추 종자에선 Ecc가 검출된 4개 품종 외에 1개 품종에서 PMMoV, TMGMV가 동시 검출되었다. 이로 인해 개발된 One-step multiplex RT-PCR은 서로 간섭 현상 없이 병원균을 효율적으로 검출할 수 있음을 보여 주었다.

• 기술사
• /
• 제24권6호
• /
• pp.97-105
• /
• 1991

The cautious blasting works had been used with emulsion explosion electric M/S delay caps. Drill depth was from 3m to 6m with Crawler Drill ø70mm on the calcalious sand stone (soft-moderate-semi hard Rock). The total numbers of fire blast were 88 round. Scale distance were induces 15.52-60.32. It was applied to propagation Law in blasting vibration as follows. Propagation Law in Blasting Vibration (Equation omitted) where V : Peak partical velocity(cm/sec) D : Distance between explosion and recording sites(m) W : Maximum Charge per delay-period of eighit milliseconds o. more(kg) K : Ground transmission constant, empirically determind on the Rocks, Explosive and drilling pattern ets. b : Charge exponents n : Reduced exponents Where the quantity D / W$^n$ is known as the Scale distance. Above equation is worked by the U.S Bureau of Mines to determine peak particle velocity. The propagation Law can be catagrorized in three graups. Cubic root Scaling charge per delay Square root Scaling of charge per delay Site-specific Scaling of charge per delay Charge and reduction exponents carried out by multiple regressional analysis. It's divided into under loom and over 100m distance because the frequency is verified by the distance from blast site. Empirical equation of cautious blasting vibration is as follows. Over 30 ‥‥‥under 100m ‥‥‥V=41(D/$^3$√W)$\^$-1.41/ ‥‥‥A Over 100 ‥‥‥‥under 100m ‥‥‥V=121(D/$^3$√W)$\^$-1.56/ ‥‥‥B K value on the above equation has to be more specified for furthur understang about the effect of explosives, Rock strength. And Drilling pattern on the vibration levels, it is necessary to carry out more tests.

• ETRI Journal
• /
• 제29권2호
• /
• pp.240-242
• /
• 2007

This letter proposes a simplified maximum likelihood detection (SMLD) scheme to improve the detection performance of multiple-input multiple-output receivers. The SMLD detects V streams according to the first detected V sub-streams. Through an ML test, the most probable stream is selected. Moreover, to detect the layer with the worst post-detection SNR accurately, reverse ordering is applied to the SMLD. Simulation results show that the performance of the Vertical Bell Laboratories layered space-time (V-BLAST) system can be improved by adopting the SMLD technique. In the case of reverse ordering, the SMLD can achieve a similar ML performance with significant reduction in computational complexity.