• Earthquakes and Structures
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• 제1권3호
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• pp.253-267
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• 2010

A novel simple approach is presented for the seismic analysis of continuous buried pipelines subject to fault ruptures. The method is based on the minimization of the total dissipated energy during faulting, taking into account the basic factors that affect the problem, namely: a) the pipe yielding under axial and bending load, through the formation of plastic hinges and axial slip; b) the longitudinal friction across the pipe-soil interface; c) the lateral resistance of soil. The advantages and drawbacks of the proposed method are highlighted through a comparison with previous approaches, as well as with finite element calculations accounting for the 3D kinematics of the pipe-soil-fault systems under large deformations. Parametric analyses are also provided to assess the relative influence of the various parameters affecting the problem.

• 한국측량학회지
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• 제28권3호
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• pp.317-328
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• 2010

본 연구는 Sandwell 및 DNSC08 해상중력모델로부터 구한 프리에어 이상으로부터 동해 지역의 완전부우게 이상을 구한 결과를 설명한 것이다. 완전부우게 보정은 부우게 보정(Bullard A), 곡률보정(Bullard B)과 지형보정(Bullard C)의 세 부분으로 구성된다. 각 보정량의 계산을 위하여 전지구 기복모델인 ETOPO1을 통해 1분 간격의 표고데이터(지형 및 수심)를 취득하여 이용하였으며, 지형(해수)의 밀도로는 $2,670kg/m^3$($1,030kg/m^3$)의 수치를 일괄적으로 적용하였다. DNSC08 모델을 이용하여 계산된 완전부우게 이상은 동해 지역에 대하여 약 -34.390~267.925mGal의 분포를 나타내었으며, Sandwell 모델의 경우 -32.446~266.967mGal의 분포를 나타내었다. 또한, 두 모델 간 완전부우게 이상의 차이는 평균 $0.036{\pm}2.373mGal$로 계산되었으며, 가장 큰 완전부우게 이상값은 가장 낮은 수심분포를 보이는 위도 $42{\sim}43^{\circ}N$ 및 경도 $137{\sim}139^{\circ}E$ 사이의 지역에서 나타났다. 이러한 수치를 통해 DNSC08과 Sandwell 모델의 중력분포가 동해 지역에 대해 매우 유사한 것을 알 수 있었으며, 위성기반의 해상중력모델이 동해 지역의 지구물리학적, 지질학적, 측지학적 특성의 해석에 효율적으로 이용될 수 있다고 판단되었다.

• 한국광학회지
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• 제31권6호
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• pp.259-267
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• 2020

실외에서 운용되는 무선 광통신 시스템의 수신기는 태양광에 직·간접적으로 노출되기 마련이다. 본 논문에서는 주광이 무선 광통신 시스템의 수신 감도에 미치는 영향을 정량적으로 분석하였다. 이를 위하여 방사 조도 측정치를 활용하여 지상에 위치한 수신기에 특정 시야각으로 직접 또는 간접적으로 입사하는 단위 면적당 태양광 전력 스펙트럼 밀도를 얻었고, 이 값을 이용하여 세기 변조/직접 검출 및 코히어런트 시스템의 성능 열화를 계산하였다. 분석 결과 주광이 수신기에 간접적으로 인가되는 경우 수신 감도 페널티가 시스템 종류에 관계없이 1.3 dB 이하였으나, 직접적으로 인가되는 경우에는 30 dB 이상의 매우 큰 수신 감도 열화가 발생하였다. 또한 이러한 수신 감도 열화는 편광자 사용 또는 광학 필터 대역폭 조절에 의해서도 거의 경감되지 않았다.

• 한국축산식품학회지
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• 제42권2호
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• pp.225-239
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• 2022

As commensal colonizers in livestock, there has been little attention on staphylococci, especially non-aureus staphylococci (NAS), contaminating meat production chain. To assess prevalence of staphylococci in retail pork and slaughterhouse carcass samples in Korea, we collected 578 samples from Korean slaughterhouses (n=311) and retail markets (n=267) for isolation of staphylococci and determined antimicrobial resistance phenotypes in all the isolates. The presence of and prevalence of fusB-family genes (fusB, fusC, fusD, and fusF) and mutations in fusA genes were examined in fusidic acid resistant isolates. A total of 47 staphylococcal isolates of 4 different species (Staphylococcus aureus, n=4; S. hyicus, n=1; S. epidermidis, n=10; Mammaliicoccus sciuri, n=32) were isolated. Fusidic acid resistance were confirmed in 9/10 S. epidermidis and all of the 32 M. sciuri (previously S. sciuri) isolates. Acquired fusidic acid resistance genes were detected in all the resistant strains; fusB and fusC in S. epidermidis and fusB/C in M. sciuri. Multi-locus sequence type analysis revealed that ST63 (n=10, 31%) and ST30 (n=8, 25%) genotypes were most prevalent among fusidic acid resistant M. sciuri isolates. In conclusion, the high prevalence of fusB-family genes in S. epidermidis and M. sciuri strains isolated from pork indicated that NAS might act as a reservoir for fusidic acid resistance gene transmissions in pork production chains.

• Asian-Australasian Journal of Animal Sciences
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• 제26권3호
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• pp.349-357
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• 2013

The aim of this study was to evaluate the efficiency of supplements containing different energy sources in relation to mineral supplementation of steers grazing guineagrass (Panicum maximum cv Tanz$\hat{a}$nia) pasture, during the dry season. The experimental design was a randomized block with three treatments and four replications. The treatments consisted of a mineral supplementation and two other supplements, one based on corn seed and the other based on soybean hulls, and provided at 0.8% of body weight. Forty-eight, 12 month-old crossbred steers with an average initial body weight of 267 kg, were assigned to twelve paddocks (1,125 ha) of guineagrass. The animals that were fed with soybean hulls and corn seed presented a greater average daily gain (0.982 and 0.937) when compared with the mineral supplementation. Soybean hulls can be used as a satisfactory food source, replacing corn as an energy source in the supplementation of beef cattle without compromising animal performance.

• 한국동물위생학회지
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• 제30권3호
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• pp.363-374
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• 2007

A biochemical characterization and antimicrobial drugs susceptibility study was conducted in four breeding kennel which was canine abortion caused by Brucella canis in Gyeongbuk province in 2003-2006. Total of 267 dogs domesticated in the four kennel were examination. Among them, 143 (53.6%) dogs were sero-positive and 25 of blood samples were isolated to Brucella canis. At amplification of 35KDa-BCSP gene using PCR, 711 bp DNA fragment was same visible in 25 isolates and B canis RM6/66. Biochemical characterization of B canis isolated was non-hemolytic, no production of $H_2S$, no fermentation of carbohydrates, catalase-positive, oxidase-positive, indol-negative, hydrolyzation of urea, reduction of nitrate and development of thionin dye medium. Using disk-diffusion method, all of 25 strains tested were found to be highly susceptible to tetracycline, aminoglycoside, quinolone, macrolide antibiotics, rifampin and ampicillin in vitro. Using PFGE with restriction enzyme Smi I, 25 isolates tested were typed to 2 pattern, S1 and S2.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2004년도 하계학술대회 논문집 Vol.5 No.1
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• pp.267-270
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• 2004

A silver indium sulfide($AgInS_2$) epilayer was grown by the hot wall epitaxy method, which has not been reported in the literature. The grown $AgInS_2$ epilayer has found to be a chalcopyrite structure and evaluated to be high qualify crystal. From the photocurrent measurement in the temperature range from 30 K to 300 K, the two peaks of A and B were only observed, whereas the three peaks of A, B, and C were seen in the PC spectrum of 10 K. These peaks. are ascribed to the band-to-band transition. The valence band splitting of $AgInS_2$ was investigated by means of the photocurrent measurement. The crystal field splitting, $\ddot{A}cr$, and the spin orbit splitting, $\ddot{A}so$, have been obtained to be 0.150 eV and 0.009 eV at 10 K, respectively. And, the energy band gap at room temperature has been determined to be 1.868 eV. Also, the temperature dependence of the energy band gap, $E_g(T)$, was determined.

• 대한의용생체공학회:의공학회지
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• 제29권4호
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• pp.267-271
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• 2008

The RF shimming technique has been used to improve the transmit RF field homogeneity in highfield MRI. In the RF shimming technique, the amplitude and phase of the driving currents in each coil element are optimized to get homogenous flip angle or uniform image intensity. The inductive and capacitive coupling between the coil elements may degrade the RF field homogeneity if not taken into account in the optimization procedure. In this paper, we have analyzed the coupling effects on the RF shimming using a sixteen-element TEM RF coil model operating at 300 MHz. We have found that the coupling effects on the RF shimming can be reduced by putting high dielectric material between the active rung and the shield.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1993년도 정기총회 및 추계학술대회 논문집 학회본부
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• pp.264-267
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• 1993

A high plasma density of $10^{12}cm^{-3}$ can be produced at the pressure of few mTorr with R. F input power of 300-400W. A radially uniform plasma to a radius of 7cm at the substrate was produced at the pressure of 1 mTorr. The electron density and temperature were confirmed with double Langmuir probe, $\mu$-wave interferometer. It has bee found that the dispersion relation N/B=constant not be applied at the low R.F input power(<600W) but can be applied at high R.F input power(>600W).

• 열처리공학회지
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• 제16권5호
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• pp.267-274
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• 2003

The effect of the thermo-mechanical treatment on the microstructural development and the electric conductivity of Cu-Ca alloys are studied for the thixoforming processed rotor of the induction motor The Cu-Ca alloys containing Ca less than 1.0wt% show the electrical conductivity higher than 80% IACS They also show broad melting range over $150^{\circ}C$ which is desirable for the thixoforming process The semi-solid microstructure of cast alloy changes from the dendrite structure to globular structure by prior deformation before reheating. The details of microstructural changes by the thermo-mechanical treatment are discussed.