• 천문학회보
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• 제46권2호
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• pp.38.2-39
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• 2021

I will presents the analysis of the gas properties of the protoplanetary disk surrounding the young low-mass (about 1.2M_sun) triple star, GG Tau A. This work makes use of ALMA observations of rotational lines of CO (¹²CO, ¹³CO and C¹⁸O) together NOEMA observations of a few dozens of other molecules. While the CO emission gives information on the molecular layer close to the disk atmosphere, its less abundant isotopologues ¹³CO and C¹⁸O bring information much deeper in the molecular layer. I will present the analysis of the morphology and kinematics of the gas disk using the CO isotopologues. A radiative transfer model of the ring in CO isotopologues will also be presented. The subtraction of this model from the original data reveals the weak emission of the molecular gas lying inside the cavity. Thus, I am able to evaluate the properties of the gas inside the cavity, such as the gas dynamics, excitation conditions, and the amount of mass in the cavity. High angular resolution observations of CO reveals sprials induced by embedded planet(s) located near the 3:2:1 mean-motion resonance that help to explain the special morphology of the circumbinary disk. I also discuss some chemical properties of the GG Tau A disk. I report the first detection of H2S and C₂S in a protoplanetary disk. The molecule abundance relative to ¹³CO of about twenties other molecules will also be given. In GG Tau A, the detections of rare molecules such as H₂S and C₂S have been probably possible because the disk is more massive (a factor about 3-5) than other disks where the molecules was searched. Such a large disk mass makes the system suitable to detect rare molecules and to study cold-chemistry in protoplanetary disks.

• 한국대기환경학회지
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• 제15권3호
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• pp.249-255
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• 1999

We sdudied effect of additives on catalytic activity in thermal catalytic de-NOx process which was composed of thermal reduction, catalytic reduction and catalytic oxidation stage. Pd-Pt/${\gamma}$-$Al_2O_3$ catalysts with the addition of transition metals(Co, Cu, Fe, Ni, W, Zn, Zr) and rare earth metals(Ce, Sr) were prepared by the conventional washcoating method. Those catalysts were characterized by CO pulse chemisorption, ICP, $N_2$ adsorption, SEM and XRD. The effect of catalyst additives on NOx removal for diesel emission was studied in thermal catalytic de-NOx process at reduction temperature(350~50$0^{\circ}C$), space velocity(5,000~20,000 $hr^{-1}$) and the engine load(0~120kW). The concentraton of CO, $CO_2$, NO and $NO_2$ in the exhaust gas increased with the engine load. On the other hand the concentration of $O_2$ decreased. The de-NOx activityof all prepared catalysts increased with respect to high CO and low $O_2$ level in the thermal reduction stage of the process. Insertion of Ce to Pt-Pd/${\gamma}$-$Al_2O_3$ catalyst showed the best activity of all the catalysts under these experimental conditions. De-NOx catalysts are effective to remove CO in addition to NOx in the catalytic reduction stage.

• 한국분말야금학회:학술대회논문집
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• 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part2
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• pp.1112-1113
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• 2006

The perovskite- type oxide $(ABO_3)$ containing transition metals on the B-site show mixed (electronic/ionic) conductivity. These mixed-conductivity oxides are promising materials for oxygen permeating membranes. The main objective of this research work is to synthesize and characterization ceramic powders of the Sr-Co-Fe-O system for methane conversion using membrane reactor. SCFO powders were synthesized from the route was based on the complex method of combination of acid EDTA and citrate and shown be available by control efficient of synthesis to performed $SrCo_{0.8}Fe_{0.2}O_{3-\delta$, moreover, it presented easy implementation, reproducibility and operation. Powder ceramic was characterized by XRD, microscopic optic, SEM and TG-DTA.

• Smart Structures and Systems
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• 제17권2호
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• pp.195-208
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• 2016

Seismic isolation systems are essentially designed to preserve structural safety, prevent occupants injury and properties damage. An active saturated LMI-based control design is proposed to attenuate seismic disturbances in base-isolated structures under saturation actuators. Using a mathematical model of an eight-storied building structure, an active control algorithm is designed. Performance evaluation of the controller is carried out in a simplified model version of a benchmark building system, which is recognized as a state-of-the-art model for numerical experiments of structures under seismic perturbations. Experimental results show that the proposed algorithm is robust with respect to model and seismic perturbations. Finally, the performance indices show that the proposed controller behaves satisfactorily and with a reasonable control effort.

• Animal Bioscience
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• 제35권1호
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• pp.138-146
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• 2022

Objective: The objective of the current study was to investigate the influences of conventional (CO) and deep litter (DE) systems on antimicrobial resistance in fecal Escherichia coli (E. coli). Methods: A cross-sectional study was carried out to detect antimicrobial resistance to E. coli in swine fecal samples in CO and DE systems located in western and northeastern Thailand. Individual rectal swab samples were taken only from healthy pigs. A total of 215 individual and healthy pigs were randomly selected for isolation and antimicrobial susceptibility test of E. coli by the disc diffusion method. The test panel included amoxicillin (AMX), colistin, doxycycline (DOX), enrofloxacin, gentamicin (GEN), kanamycin, neomycin (NEO), and trimethoprim-sulfamethoxazole (SXT). Results: There were significant (p<0.05) lower resistance levels for GEN, NEO, and SXT in the DE farms compared to those in the CO farms. There was a lower number of antimicrobial resistance agents (p<0.001) in the DE farms compared to those in the CO farms. This result was consistent with those in western (p<0.01) and northeastern (p<0.01) Thailand. Overall, antibiograms of AMX-SXT and AMX-DOX-SXT were found in the CO (19.09% and 20.91%, respectively) and the DE (16.19% and 24.76%, respectively) farms. No antimicrobial resistance (5.71%) was found and AMX (13.33%) resistant pigs in the DE farms, whereas the pattern of AMX-GEN-SXT (6.36%) and AMX-DOX-GEN-SXT (11.82%) resistant pigs was found in the CO farms. Conclusion: The DE system for pig farming was superior to conventional pig farming by lowering the resistance level of fecal E. coli to GEN, NEO, and SXT, with decreasing the number of antimicrobial resistance agents and inducing a small proportion of pigs to be free from antimicrobial resistance.

• Journal of Communications and Networks
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• 제16권5호
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• pp.523-533
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• 2014

Orthogonal frequency division multiple access (OFDMA) is a promising technique, which can provide high downlink capacity for the future wireless systems. The total capacity of OFDMA can be maximized by adaptively assigning subchannels to the user with the best gain for that subchannel, with power subsequently distributed by water-filling. In this paper, we propose the use of composite differential evolution (CoDE) algorithm to allocate the subchannels. The CoDE algorithm is population-based where a set of potential solutions evolves to approach a near-optimal solution for the problem under study. CoDE uses three trial vector generation strategies and three control parameter settings. It randomly combines them to generate trial vectors. In CoDE, three trial vectors are generated for each target vector unlike other differential evolution (DE) techniques where only a single trial vector is generated. Then the best one enters the next generation if it is better than its target vector. It is shown that the proposed method obtains higher sum capacities as compared to that obtained by previous works, with comparable computational complexity.

• BMB Reports
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• 제37권3호
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• pp.320-334
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• 2004

StMBF1 (Solanum tuberosum multiprotein bridging factor 1) is a plant member of the MBF1 family of transcriptional co-activators. In an attempt to understand the role of StMBF1, we analyzed its interaction with plant transcription factors of the homeodomain-leucine zipper (Hd-Zip) family, a group of proteins with a typical leucine zipper motif adjacent to a homeodomain. StMBF1 is able to interact in vitro with the Hd-Zip protein Hahb-4 both in the presence and absence of DNA. Upon binding, StMBF1 increases the DNA binding affinity of Hahb-4, and of another plant homeodomain containing protein from the GL2/Hd-Zip IV family, HAHR-1. The biological role of interactions is discussed in this paper.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2008년도 하계종합학술대회
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• pp.24-25
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• 2008

An Electrostatic discharge (ESD) protection has been a very important reliability issue in microelectronics, especially for RF (Radio Frequency) integrated circuits (ICs). This paper reviews design and analysis of on-chip ESD (electrostatic discharge) protection circuits for RF applications. Key issues in RF ESD protection, design methods, and RF ESD protection solutions are discussed.

• Computers and Concrete
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• 제4권3호
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• pp.243-257
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• 2007

A novel method for recognition, characterization, and quantification of deterioration in bridge components and laboratory concrete samples is presented in this paper. The proposed scheme is based on grey level co-occurrence matrix texture analysis using Haar's discrete wavelet transform on concrete imagery. Each image is described by a subset of band-filtered images containing wavelet coefficients, and then reconstructed images are employed in characterizing the texture, using grey level co-occurrence matrices, of the different types and degrees of damage: map-cracking, spalling and steel corrosion. A comparative study was conducted to evaluate the efficiency of the supervised maximum likelihood and unsupervised K-means classification techniques, in order to classify and quantify the deterioration and its extent. Experimental results show both methods are relatively effective in characterizing and quantifying damage; however, the supervised technique produced more accurate results, with overall classification accuracies ranging from 76.8% to 79.1%.

• 한국재료학회지
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• 제26권6호
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• pp.298-305
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• 2016

In this work, recent progress on graphene/metal oxide composites as advanced materials for $HgCl_2$ and $CO_2$ capture was investigated. Density Functional Theory calculations were used to understand the effects of temperature on the adsorption ability of $HgCl_2$ and water vapor on $CO_2$ adsorption on CaO (001) with reinforced carbon-based nanostructures using B3LYP functional. Understanding the mechanism by which mercury and $CO_2$ adsorb on graphene/CaO (g-CaO) is crucial to the design and fabrication of effective capture technologies. The results obtained from the optimized geometries and frequencies of the proposed cluster site structures predicted that with respect to molecular binding the system possesses unusually large $HgCl_2$ ($0.1-0.4HgCl_2g/g$ sorbent) and $CO_2$ ($0.2-0.6CO_2g/g$ sorbent) uptake capacities. The $HgCl_2$ and $CO_2$ were found to be stable on the surface as a result of the topology and a strong interaction with the g-CaO system; these results strongly suggest the potential of CaO-doped carbon materials for $HgCl_2$ and $CO_2$ capture applications, the functional gives reliable answers compared to available experimental data.