• Journal of Mushroom
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• v.11 no.2
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• pp.69-76
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• 2013

Pholiota species were collected from different geographical regions of the world. Genetic diversity and phylogenetic relationships were analyzed by rDNA-ITS sequences and RAPD polymorphism. The sizes of rDNA-ITS PCR amplicons of Pholiota spp. varied from 233~271, 158~223 and 174~219 bp, respectively. A phylogenetic tree was constructed on the ITS region sequences and Pholiota strains were classified into 8 clusters. Twenty strains in seven Pholiota spp. were classified into seven clusters by RAPD polymorphism using 15 arbitrary primers. Our experimental results suggested that rDN-ITS and RAPD analysis are useful tool for classifying Pholiota spp. and strains.

• 한국신재생에너지학회:학술대회논문집
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• 2010.06a
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• pp.111.1-111.1
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• 2010

석탄가스화복합발전(IGCC: Integrated Gasification Combined Cycle)의 고온 고압 합성가스로부터 $CO_2$를 저비용으로 포집하기 위한 연소전 포집 기술 중 유동층 촉진수성가스전환(SEWGS) 공정이 제안되어 연구개발 중에 있다. 연소전 $CO_2$ 포집을 위한 SEWGS 공정은 동일한 2탑 순환 유동층 반응기에서 고온 고압의 합성가스($H_2$, CO)를 유동층 WGS 촉매를 사용하여 CO를 $CO_2$로 전환하는 동시에 전환반응으로 생성된 $CO_2$를 흡수제를 이용하여 포집하는 기술이다. 본 연구는 $CO_2$ 회수와 WGS 반응이 동시에 이루어지는 공정에 적용 가능한 건식 재생 흡수제 및 유동층 WGS 촉매 개발을 목표로 $CO_2$ 흡수제(P Series) 및 WGS 촉매(PC Series) 조성을 제안하고 분무건조기를 이용하여 6~8kg/batch로 성형 제조하였다. 제조된 $CO_2$ 흡수제 및 촉매의 특성 평가 결과 내마모도(Attrition resistance)를 포함한 물리적 특성이 유동층 공정의 요구조건을 만족하는 결과를 얻을 수 있었다. 또한, 모사 석탄 합성가스를 이용하여 20bar, $200^{\circ}C$ 흡수/$400^{\circ}C$ 재생 조건에서 열중량 분석기(TGA) 및 가압 유동층(Fluidized-bed) 반응기를 통한 흡수제의 $CO_2$ 흡수능 평가를 수행하였다. 그 결과 내마모도(AI) 3% 이하로 기계적 강도가 우수하며, $CO_2$ 흡수능 17.6 wt%(TGA) 및 11wt%(가압 유동층)를 나타냈다. 유동층 WGS 특성 평가 결과 내마모도가 7~35%로 우수하였고, CO 전환율은 $200^{\circ}C$에서 80% 이상으로, 유동층 SEWGS 공정에 적용 가능한 특성을 확인하였다.

• Journal of Chest Surgery
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• v.53 no.5
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• pp.306-309
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• 2020

A 59-year-old man presented for possible durable ventricular assist device (VAD) implantation. He had previously been diagnosed with congenitally corrected transposition of the great arteries, a ventricular septal defect, an atrial septal defect, pulmonary valve stenosis, and aortic valve regurgitation. In the previous 22 years, he had undergone palliative cardiac surgery 3 times. VAD implantation as a bridge to transplantation was planned. Owing to severe adhesions, mesocardia, a left ascending aorta, and moderate aortic regurgitation, we performed VAD implantation and aortic valve closure via a dual left thoracotomy and partial sternotomy.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.13 no.1
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• pp.215-220
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• 2013

In this paper, the signal reception environment of the satellite communications was analyzed on urban, suburban and rural environment. The correct analysis of received environment is very important in the satellite communications because the presence of various attenuation factors. Analyze attenuation factor through the simulation and that apply to each receiving environment. The urban and suburban various received sensitivity is determined according to building height and density. Moreover, attenuation occurs in rural areas due to the mountainous and vegetation. In this paper, we analysis of variety receiving environment according to movement of the ground station and the satellites can be utilized to provide stable multimedia services.

• Current Photovoltaic Research
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• v.2 no.1
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• pp.8-13
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• 2014

ZnSe/$Zn_3P_2$ heterojunctions with a substrate configuration were fabricated using a series of cost-effective processes. Thin films of ZnTe and $Zn_3P_2$ were successively grown by close-spaced sublimation onto Mo-coated glass substrates. ZnSe layers thinner than 100nm were formed by annealing the $Zn_3P_2$ films in selenium vapor. Surface selenization generated a high density of micro-cracks which, along with voids, provided shunt paths and severely deteriorated the diode characteristics. Annealing the $Zn_3P_2$ film at $300^{\circ}C$ in a $ZnCl_2$ atmosphere before surface selenization produced a dense microstructure and prevented micro-crack generation. The mechanism of micro-crack generation by the selenization was described and the suppression effect of $ZnCl_2$ treatment on the micro-crack generation was explained. ZnSe/$Zn_3P_2$ heterojunctions with low leakage current ($J_0$ < $1{\mu}A/cm^2$) were obtained using an optimized surface selenization process with $ZnCl_2$ treatment. However, the series resistance was very high due to the presence of an electrical barrier between the ZnTe and $Zn_3P_2$ layers.

• Geomechanics and Engineering
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• v.12 no.5
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• pp.849-862
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• 2017

With growing interests in using bacterial biopolymers in geotechnical practices, identifying mechanical properties of soft gel-like biopolymers is important in predicting their efficacy in soil modification and treatment. As one of the promising candidates, dextran was found to be produced by Leuconostoc mesenteroides. The model bacteria utilize sucrose as working material and synthesize both soluble and insoluble dextran which forms a complex and inhomogeneous polymer network. However, the traditional rheometer has a limitation to capture in situ properties of inherently porous and inhomogeneous biopolymers. Therefore, we used the particle tracking microrheology to characterize the material properties of the dextran polymer. TEM images revealed a range of pore size mostly less than $20{\mu}m$, showing large pores > $2{\mu}m$ and small pores within the solid matrix whose sizes are less than $1{\mu}m$. Microrheology data showed two distinct regimes in the bacterial dextran, purely viscous pore region of soluble dextran and viscoelastic region of the solid part of insoluble dextran matrix. Diffusive beads represented the soluble dextran dissolved in an aqueous phase, of which viscosity was three times higher than the growth medium viscosity. The local properties of the insoluble dextran were extracted from the results of the minimally moving beads embedded in the dextran matrix or trapped in small pores. At high frequency (${\omega}>0.2Hz$), the insoluble dextran showed the elastic behavior with the storage modulus of ~0.1 Pa. As frequency decreased, the insoluble dextran matrix exhibited the viscoelastic behavior with the decreasing storage modulus in the range of ${\sim}0.1-10^{-3}Pa$ and the increasing loss modulus in the range of ${\sim}10^{-4}-1\;Pa$. The obtained results provide a compilation of frequency-dependent rheological or viscoelastic properties of soft gel-like porous biopolymers at the particular conditions where soil bacteria produce bacterial biopolymers in subsurface.

• Journal of Environmental Science International
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• v.23 no.11
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• pp.1919-1927
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• 2014

In order to decide the location of appropriate onshore wind farm with higher potential wind energy, several decision processes using Geographic Information System (GIS) including Digital Elevation Map (DEM) were proposed and we also estimated the wind resources through the proposed decision process. Decision process consists with three steps. First step is excluding inappropriate location geographically using DEM data including SRTM (Shuttle Radar Topography Mission) terrain data, landslide, land-use, roadway, and forest road data. And the second step of decision process is consideration of the difficulty caused by the natural environmental problem. This step is carried out using ECVAM (Environmental Conservation Value Assessment Map) data. And final step is determination of the most suitable location through the Moving Suitability Identification Method (MSIM) based on the moving potentially estimated wind resources area. Proposed decision process was applied over the Korean Peninsula. Wind resource potential estimated by the first and the second step is cases shows 35.09 GW and 7.17 GW, respectively, and the total evaluated energy from the all proposed step were 0.43 GW and 1.87 GW for the 3 km and 1.5 km geographical grid size, respectively.

• Journal of the Korean Institute of Intelligent Systems
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• v.23 no.3
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• pp.202-207
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• 2013

In the paper, we design a autonomous mobile robot for freight transportation and propose an operation method of the robot in the warehouse. In order to implement autonomous navigation, it is needed to recognize the position of the robot and track the path to the target. Previous methods are hard to change the workspace environment and need high cost to install and keep a maintenance of the system. The lifter of freight transportation robot is designed to load and unload a baggage through up and down motion. Also, ultrasonic sensor, RFID, QR-code and camera sensor is used to carry out various functions while the robot navigates in the various environment. We design an operation method of the mobile robot in order to effectively arrive a goal position and transport a freight. The proposed methods are verified through various experiments.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.52 no.1
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• pp.112-121
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• 2007

Grain filling is a crucial factor that determines grain yield in crops since it is the final process directly associated with crops' yield performance. Grain filling process can be characterized by the interaction of rate and duration of grain filling. This study was conducted, using 16 temperate japonica rice genotypes, with aims to (1) seek variations in grain filling duration and rate on area basis, (2) compare the contribution of grain filling duration and rate to grain yield, and (3) examine the influence of temperature and solar radiation for effective grain filling on grain yield in relation to grain filling duration and rate. Grain filling rate and duration exhibited highly significant variations in the ranges of $20.7{\sim}46.3\;g\;m^{-2}d^{-1}\;and\;11.2{\sim}35.5$ days, respectively, depending on rice genotypes. Grain yield on unit area basis was associated positively with grain filling duration but negatively with grain filling rate. Grain filling rate and duration were negatively correlated with each other. Final grain weight increased linearly with the rise in both cumulative mean temperature and cumulative solar radiation for effective grain filling. Higher cumulative mean temperature and cumulative solar radiation for effective grain filling were the results of longer grain filling duration, but not necessarily higher daily mean temperature and daily solar radiation for effective grain filling. Grain filling rate demonstrated an increasing tendency with the rise in daily mean temperature for effective grain filling but their relationship was not obviously clear. It was concluded that grain filling duration, which influenced cumulative mean temperature and cumulative solar radiation for effective grain filling, was the main factor that determined grain yield on unit area basis in temperate Japonica rice.

• Korean Journal of Clinical Laboratory Science
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• v.48 no.1
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• pp.41-48
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• 2016

Motor evoked potential of spinal surgery is known to cause damage due to the movement path of the continuous scan operation and surgery can be performed with minimized disability after surgery. However, if it is not at all formed at the wave motion evoked potential can occur during surgery and, in some cases the size of the waveform to be measured is very small and intermittent. In this case, the surgery cannot provide information about whether there is neurological damage. Increased intensity of the wave-induced motion of the dislocation does not occur if it appears in a very small amplitude stimulus, but changing the inspection area that electrical stimulation of the waveform changes could not be found. However, stimulation of a wide area in the cerebral cortex was found to occur with a waveform in the patients who underwent examination. Through this study, we propose a useful motor evoked potential test. From November to December 2015 three spine surgery patients visited Samsung Medical Center as neurosurgery patients with omission discomfort, gait disturbance, and no symptom of strength before surgery. In spine surgery patients with motor grade weakness, when motor evoked potential waveform has not been measured, in examination of the site of electrical stimulation of the cerebral cortex from entering the C3+C5/C4+C6 or C3+C1/C4+C2 if by the activity of more motor neuron unit, it was found that the waveform is better formed.