• Mycobiology
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• 제33권4호
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• pp.215-222
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• 2005

Variability in growth and sporulation of five isolates of Arthrobotrys dactyloides was studied on five agar, 6 bran and 5 grain media. Potato dextrose agar (PDA) supported maximum growth of isolate A, C and E, while growth of isolate Band D was significantly lower on this medium. On Czapek's agar and yeast glucose agar media the differentiation in the isolates in relation to growth was poor than PDA. The other two media showed much poorer differentiation. On Czapek's agar medium, sporulation was recorded in isolate B only, whereas other isolates showed rare sporulation. Among the bran media, pea bran agar medium supported maximum growth of all the isolates except isolate B. Gram and rice bran agar media were next best. However, the growth of isolate B on the gram bran agar medium was more or less equal as other isolates. On pigeon pea bran agar medium, isolate E failed to grow while other isolates recorded poor growth. On lentil bran agar medium, only isolate Band D recorded little growth, whereas other isolates failed to grow. All the isolates recorded good sporulation on bran agar media except pigeon pea and lentil bran agar media. The grain agar media supported moderate to very good growth of all the isolates. In general isolate B remained slow growing on these media except gram grain and sorghum grain agar media on which growth of this isolate was comparable to other isolates. Sporulation in general, was good on all the grain agar media. Among different substrates screened, barley grain and pea bran were found superior to others for mass culture of isolate A of A. dactyloides.

• Nuclear Engineering and Technology
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• 제53권6호
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• pp.1846-1857
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• 2021

Ultrasonic nondestructive testing is important for monitoring the structural integrity of dissimilar metal welds (DMWs) in pressure vessels and piping in nuclear power plants. However, there is a low probability of crack detection via inspection of DMWs using ultrasonic waves because the grain structures (grain orientations) of the weld area cause distortion and splitting of ultrasonic beams propagating in anisotropic media. To overcome this issue, the grain orientation should be known, and a precise ultrasonic wave simulation technique in anisotropic media is required to model the distortion and splitting of the waves accurately. In this study, a method for nondestructive prediction of the DMW grain orientations is presented for accurate simulation of ultrasonic wave propagation behavior in the weld area. The ultrasonic wave propagation behavior in anisotropic media is simulated via finite-element analysis when ultrasonic waves propagate in a transversely isotropic material. In addition, a methodology to predict the DMW grain orientation is proposed that employs a simulation technique for ultrasonic wave propagation behavior calculation and an optimization technique. The simulated ultrasonic wave behaviors with the grain orientations predicted via the proposed method demonstrate its usefulness. Moreover, the method can be used to determine the focal law in DMWs.

• Journal of Magnetics
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• 제7권3호
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• pp.106-114
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• 2002

To reduce the grain size and the media noise in a typical CrMo/CoCrPtB longitudinal media, a sputtering process which includes the exposure of oxygen onto the surface of CrW$_x$ (x=0, 25, 50, 75, 100 at.%) and CrTi$_{15}$ seedlayers with the thickness of 0.5 nm have been utilized. The main results are: (1) the media grain size and the media noise are reduced when using CrW$_x$ (x=0, 25, 50 at.%) seedlayers, and not reduced when using CrTils or CrW$_x$ (x=75, 100 at.%) seedlayers, (2) AES and RHEED results suggest that W seedlayer, which has the highest melting point, forms layer-like film with very small and dense island grain, due to its high free surface energy and low mobility. On the other hand, CrW$_{50}$ and Cr seedlayers, which have lower melting point than W seedlayer, form island film, (3) to effectively reduce the media grain size and improve the media signal to noise ratio, it is essential to utilize a very thin Cr-based seedlayer with high affinity for oxygen and which forms island-like structure, such as CrW$_{50}$ seedlayer.

• 한국버섯학회지
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• 제2권1호
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• pp.10-14
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• 2004

버섯을 이용한 기능성 전통 장류발효식품의 개발 및 버섯가공산업 육성을 위한 기초자료를 제공하고자 상식하고있는 7종류의 곡물배지에 느타리버섯 균사체 배양을 행하고 그 배양추출물의 생리활성 등을 검토하였다. 곡물을 냉수에 4시간 수침시킨 후 물 빼기를 한 다음 곡물 중량비에 대하여 수분을 25%(V/W) 전후로 첨가하고 증자시간을 30분 행하는 것이 느타리버섯 균사생육에 효과적이었다. 7종류의 곡물배지에 느타리버섯 균사를 고체 배양한 결과 조와 보리쌀 배지에서 생육이 가장 왕성하였고 그 다음은 대두박과 검정콩 배지로 나타났으며 밀, 옥수수 및 현미배지에서는 생육이 늦은 것으로 나타났다. 느타리버섯 균사추출물들이 폐암세포의 생육에 미치는 영향을 검토한 결과 옥수수, 대두박, 현미, 보리쌀 및 검정콩 배지에서 비교적 높은 항암성을 나타내었고, 조와 밀의 배지에서는 낮은 항암성을 나타내었다. 혈전용해활성은 대두박, 밀, 조, 보리쌀, 현미, 검정콩, 옥수수배지의 순으로 높게 나타났으며, 병원성 세균에 대한 항균활성은 Pseudomonas aeruginosa 및 Staphylococcus aureus에 대하여 높게 나타났다.

• Journal of Magnetics
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• 제3권3호
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• pp.96-98
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• 1998

In this paper a structurally coupled and magnetically decoupled Ba-ferrite thin film medium is proposed to evade the superparamagnetic limit and reduce media noise. The proposed medium consists of ferrimagnetic Ba-ferrite nano-grains (< 10 nm) and a non-magnetic grain boundary material. Magnetic grains are crystallographically matched with the grain boundary material. Spherical or cubic shaped Ba-ferrite particle is also proposed for above 100 Kfci particulate recording application.

• 한국방송∙미디어공학회:학술대회논문집
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• 한국방송공학회 2013년도 추계학술대회
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• pp.169-171
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• 2013

최근 Full-HD TV, UHDTV의 보급에 따라 고화질 영상에 대한 수요가 증가하고 있으며 N-Screen 서비스의 확장으로 고화질 영상을 빠르게 전송하는 문제의 중요성은 더욱 커지고 있다. 고화질 영상을 빠르게 전송하기 위해서는 압축 효율의 향상이 필요한데, 일반적으로 영상에 잡음이 많을 때에는 압축 효율이 떨어진다. 본 논문에서는 다양한 원인의 잡음들 중에 film grain noise에 초점을 맞추어 이를 조절하여 영상압축의 효율을 높이는 방법을 연구한다. film grain은 영화촬영 방법 및 환경 등에 따라 강도가 달라지기도 하지만 필름으로 촬영한 모든 영화에서 쉽게 관찰할 수 있으며 앞으로도 계속 포함이 될 것으로 예상되고, 디지털 영화의 경우에도 저조도에서는 이와 비슷한 특성의 잡음이 발생한다. 재안하는 방법에서는 film grain이 포함된 영상에서 grain을 추출/제거한 영상을 압축하며 추출한 film grain에서 작은 영역을 선택하여 sample grain을 만든 후 별도로 압축한다. 디코더에서 grain을 없앤 영상만을 보여줄 수 있지만, 경우에 따라 grain이 없으면 심미적으로 오히려 좋지 않은 결과가 보이기도 한다. 따라서 압축을 푼 후에는 sample grain에서 원본 영상 크기의 grain을 합성한 후 grain을 제거한 영상과 더하여 grain이 포함된 영상을 재 생성한다. 실험한 결과 원본과 유사한 grain이 생성되면서 압축효율이 향상됨을 확인할 수 있다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2000년도 하계학술대회 논문집
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• pp.208-211
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• 2000

We prepared Co-Cr-Ta and Co-Cr-Ta/Ti thin film for perpendicular magnetic recording media by facing targets sputtering system (FTS system). Ti underlayer effects on crystallographic and magnetic characteristics of Co-Cr-Ta perpendicular magnetic recording media have been investigated. Crystallgraphic and magnetic characteristic of prepared thin films were evaluated by x-ray diffractometry(XRD), vibrating sample magnetometer(VSM) and kerr hysteresis loop measurement. The coercivity and anisotropy field increase by introduced Ti underlayer when substrate temperature is higher than 150$^{\circ}C$. The c-axis dispersion angle and grain size of Co-Cr-Ta/Ti thin film is decrease than Co-Cr-Ta when substrate temperature is higher than 100$^{\circ}C$. Consequently, the use of a Ti underlayer highly orientated can be improved crystallographic and magnetic characteristics of Co-Cr -Ta perpendicular media layer.

• 한국염색가공학회지
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• 제19권2호
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• pp.24-31
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• 2007

This paper addresses factors of line image quality on grain leather printed via inkjet printer. Lines were printed onto coated leather media, and line width, edge blurriness, and edge raggedness were evaluated for line image quality. Various factors influenced to wetting and capillary wicking were studied and found out that wicking through capillary between fibers causes significant feathering on leather surface similar with pulp capillary in copy Paper. Polyurethane and acrylic resin coating resulted good image qualify by reducing capillary wicking. The mixture of polyurethane and acrylic resin applied on grain leather satisfied with both image quality and surface hand. $AllWrite^{TM}$ ink brought best results of image quality, comparing with $VeraPrint^{TM}$ ink and $JetWrite^{TM}$ ink.

• 한국미생물·생명공학회지
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• 제51권4호
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• pp.449-456
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• 2023

Sugar or dextrose increases the cost of production of xanthan gum by Xanthomonas campestris. Brewers' Spent Grain (BSG) was chosen as a source of fermentable sugars. BSG is a significant industrial by-product generated in large quantities from the breweries. Primarily used as animal feed due to its high fiber and protein content, BSG holds great potential as an economically and ecologically sustainable substrate for fermenting biomolecules. This study explores BSG's potential as a cost-effective carbon source for producing xanthan, utilizing Xanthomonas campestris NCIM 2961. An aqueous extract was prepared from BSG and inoculated with the bacterium under standard fermentation conditions. After fermentation, xanthan gum was purified using a standard protocol. The xanthan yield from BSG media was compared to that from MGYP media (control). The fermentation parameters, including pH, temperature, agitation and duration were optimized for maximum xanthan gum yield by varying them at different levels. Following fermentation, the xanthan gum was purified from the broth by alcoholic precipitation and then dried. The weight of the dried gum was measured. The obtained xanthan from BSG under standard conditions and commercial food-grade xanthan were characterized using FTIR. The highest xanthan yields were achieved at 32 ℃, pH 6.0, and 72 h of fermentation at 200 rpm using BSG media. The FTIR spectra of xanthan from BSG media closely resembled that of commercial food-grade xanthan. The results confirm the potential of BSG as a cost-effective alternative carbon source for xanthan production, thereby reducing production costs and solid waste.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2005년도 총회 및 춘계학술발표회
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• pp.446-450
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• 2005

Hydraulic conductivity of unconsolidated media can be determined by aquifer tests, laboratory tests and empirical equations based on grain size analysis. Commonly, the different methods give different hydraulic conductivities. Grain size measurements were done to determine hydraulic conductivity, using 184 soil samples collected from eight boreholes in a riverbank filtration area, Daesan-Myeon, Changwon City, Korea, Pumping tests were conducted at the riverbank filtration area. The average hydraulic conductivity by the empirical relations from grain size measurements comes out around $10^{-2}m/s$, 22 to 55 times higher than by the pumping test analyses. The hydraulic conductivity obtained from the empirical equations is interpreted to have a relationship with steady-state condition while that obtained from the pumping tests is interpreted to have a relationship with unsteady-state condition. Thus, hydraulic conductivity obtained from various methods should be critically analyzed for reasonable management of groundwater development.