• Natural Product Sciences
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• v.24 no.1
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• pp.47-53
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• 2018

Callophylum symingtonianum (Guttiferae), an evergreen broad-leaved tree that usually grows in hill forests, can be found distributed in the Malay Peninsula. The barks, leaves, flowers and seeds is often used medicinally to treat diarrhea and rheumatism. In the present study, we isolated two inophyllum type coumarins, 12-O-ethylinophyllum D (1) and iso-soulattrolide (2) from the stembarks of C. symingtonianum together with their antibacterial activity. The compounds were isolated by chromatographic methods on a silica gel. The structures were established by spectroscopic methods including UV, IR, (1D and 2D) NMR and mass spectrometry as well as by comparison with several literature sources. The antibacterial activity of those compounds was tested using a disc-diffusion assay against Staphylococcus aureus, Bacillus cereus, Escherichia coli and Pseudomonas aeruginosa. Both compound exhibited mild inhibition against P. aeruginosa with both $111{\mu}g/ml$ MIC value. Compound 2 also inhibits S. aureus with $25{\mu}g/ml$ MIC value.

• Bulletin of the Korean Chemical Society
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• v.33 no.6
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• pp.1879-1884
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• 2012

The kinetic studies on the reactions of dipropyl chlorophosphate (3O) with substituted anilines ($XC_6H_4NH_2$) and deuterated anilines ($XC_6H_4ND_2$) have been carried out in acetonitrile at $55.0^{\circ}C$. The obtained deuterium kinetic isotope effects (DKIEs; $k_H/k_D$) are primary normal ($k_H/k_D$ = 1.09-1.01) with the strongly basic anilines while secondary inverse ($k_H/k_D$ = 0.74-0.82) with the weakly basic anilines. The steric effects of the two ligands on the rates are extensively discussed for the anilinolyses of the ($R_1O$)($R_2O$)P(=O or S)Cl-type chlorophosphates and chlorothiophosphates. A concerted mechanism is proposed with a frontside nucleophilic attack involving a hydrogen-bonded four-center-type transition state for the strongly basic anilines and with a backside attack transition state for the weakly basic anilines on the basis of the DKIEs, primary normal and secondary inverse with the strongly and weakly basic anilines, respectively.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.11 no.2
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• pp.1118-1133
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• 2017

Computer vision-based human activity recognition (HAR) has become very famous these days due to its applications in various fields such as smart home healthcare for elderly people. A video-based activity recognition system basically has many goals such as to react based on people's behavior that allows the systems to proactively assist them with their tasks. A novel approach is proposed in this work for depth video based human activity recognition using joint-based motion features of depth body shapes and Deep Belief Network (DBN). From depth video, different body parts of human activities are segmented first by means of a trained random forest. The motion features representing the magnitude and direction of each joint in next frame are extracted. Finally, the features are applied for training a DBN to be used for recognition later. The proposed HAR approach showed superior performance over conventional approaches on private and public datasets, indicating a prominent approach for practical applications in smartly controlled environments.

• Journal of Microbiology and Biotechnology
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• v.17 no.2
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• pp.207-217
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• 2007

The Saccharomyces0 cerevisiae KNU5377 strain, which was isolated from spoilage in nature, has the ability to convert biomass to alcohol at high temperatures and it can resist against various stresses [18, 19]. In order to understand the defense mechanisms of the KNU5377 strain under menadione (MD) as oxidative stress, we used several techniques for study: peptide mass fingerprinting (PMF) by matrix-assisted laser desorption/ionization-time of flight (MALDI-TOF) mass spectrometry (MS) followed by two-dimensional (2D) gel electrophoresis, liquid chromatography electrospray ionization tandem mass spectrometry (LC-ESI-MS/MS), and surface-enhanced laser desorption ionization-time of flight (SELDI-TOF) technology. Among the 35 proteins identified by MALDI-TOF MS, 19 proteins including Sod1p, Sod2p, Tsa1p, and Ahp1p were induced under stress condition, while 16 proteins were augmented under normal condition. In particular, five proteins, Sod1p, Sod2p, Ahp1p, Rib3p, Yaf9p, and Mnt1p, were induced in only stressed cells. By LC-ESI-MS/MS analysis, 37 proteins were identified in normal cells and 49 proteins were confirmed in the stressed cells. Among the identified proteins, 32 proteins were found in both cells. Five proteins including Yel047cp and Met6p were only upregulated in the normal cells, whereas 17 proteins including Abp1P and Sam1p were elevated in the stressed cells. It was interesting that highly hypothetical proteins such as Ynl281wp, Ygr279cp, Ypl273wp, Ykl133cp, and Ykr074wp were only expressed in the stressed cells. SELDI-TOF analysis using the SAX2 and WCX2 chips showed that highly multiple-specific protein patterns were reproducibly detected in ranges from 2.9 to 27.0 kDa both under normal and stress conditions. Therefore, induction of antioxidant proteins, hypothetical proteins, and low molecular weight proteins were revealed by different proteomic techniques. These results suggest that comparative analyses using proteomics might contribute to elucidate the defense mechanisms of KNU5377 under MD stress.

• Journal of Forest and Environmental Science
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• v.35 no.3
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• pp.159-172
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• 2019

Madhupur National Park (MNP) is one of the last remaining patches of old-growth natural Sal forest left in Bangladesh where the forest is tropical moist deciduous type. A study was revealed to assess the tree species diversity and composition in this area. For determining tree species the study was conducted through extensive random quadrat survey methods with $20m{\times}20m$ sized plots. Results of the study indicated that there were 139 tree species belonging to 100 genera and 40 families. The quadrat survey assessed the basal area, stem density, diversity indices and importance value index of the tree species having ${\geq}5cm$ D.B.H (Diameter at Brest Height). The basal area and stem density of the tree species were $20.689{\pm}1.08m^2/ha$ and $1412.93{\pm}64.27stem\;ha^{-1}$ while, diversity indices, i.e. Shannon-Wiener's diversity, Simpson's evenness, Margalef's species richness and Pielou's dominance indices indicated poor diversity in comparison to that of other PAs (Protected Areas) in South-Eastern region of Bangladesh. The structural composition based on height and D.B.H through reverse-J shaped curve indicated higher regeneration and recruitment but removal of trees of large growth classes. Sal (Shorea robusta) was the most dominant tree species that accounts 75% of the total tree individuals in the natural forest patches. However, some associates of Sal, i.e. Bhutum (Hymenodictyon orixensis), Gadila (Careya arborea), and Kusum (Schleichera oleosa) etc. were seemed to be rare in MNP.

• Bulletin of the Korean Chemical Society
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• v.29 no.8
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• pp.1554-1560
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• 2008

The probe diffusion and friction constants of methyl yellow (MY) in liquid n-alkanes of increasing chain length were calculated by equilibrium molecular dynamics (MD) simulations at temperatures of 318, 418, 518 and 618 K. Lennard-Jones particles with masses of 225 and 114 g/mol are modeled for MY. We observed that the diffusion constant of the probe molecule follows a power law dependence on the molecular weight of nalkanes, DMY${\sim}M^{-\gamma}$ well. As the molecular weight of n-alkanes increases, the exponent $\gamma$ shows sharp transitions near n-dotriacontane ($C_{32}$) for the large probe molecule (MY2) at low temperatures of 318 and 418 K. For the small probe molecule (MY1) $D_{MY1}$ in $C_{12}$ to C80 at all the temperatures are always larger than Dself of n-alkanes and longer chain n-alkanes offer a reduced friction relative to the shorter chain n-alkanes, but this reduction in the microscopic friction for MY1 is not large enough to cause a transition in the power law exponent in the log-log plot of DMY1 vs M of n-alkane. For the large probe molecule (MY2) at high temperatures, the situation is very similar to that for MY1. At low temperatures and at low molecular weights of n-alkanes, $D_{MY2}$ are smaller than $D_{self}$ of n-alkanes due to the relatively large molecular size of MY2, and MY2 experiences the full shear viscosity of the medium. As the molecular weight of n-alkane increases, $D_{self}$ of n-alkanes decreases much faster than $D_{MY2}$ and at the higher molecular weights of n-alkane, MY2 diffuses faster than the solvent fluctuations. Therefore there is a large reduction of friction in longer chains compared to the shorter chains, which enhances the diffusion of MY2. The calculated friction constants of MY1 and MY2 in liquid n-alkanes supported these observations. We deem that this is the origin of the so-called“solventoligomer”transition.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.12 no.6
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• pp.890-898
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• 2001

4H-SiC(silicon carbide) MESFET large signal model was studied using modified Materka-Kacprzak large signal MESFET model. 4H-SiC MESFET device simulation have been conducted by Silvaco\`s 2D device simulator, ATLAS. The result is modeled using modified Materka large signal model. simulation and modeling results are -8 V pinch off voltage, under V$\_$GS/=0 V, V$\_$DS/=25 V conditions, I$\_$DSS/=270 mA/mm, G$\_$m/=52.8 ms/mm were obtained. Through the power simulation 2 GHz, at the bias of V$\_$GS/-4 V md V$\_$DS/=25 V, 10 dB Gain, 34 dBm (1dB compression point)output porter, 7.6 W/mm power density, 37% PAE(power added efficiency) were obtained.7.6 W/mm power density, 37% PAE(power added efficiency) were obtained.d.

• Wind and Structures
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• v.29 no.1
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• pp.43-53
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• 2019

Vortex-induced vibration of three circular cylinders (each of diameter D) in an equilateral triangular arrangement is investigated using the immersed boundary method. The cylinders, with one placed upstream and the other two side-by-side downstream, are free to vibrate in the cross-flow direction. The cylinder center-to-center spacing L is adopted as L/D = 2.0. Other parameters include the Reynolds number Re = 100, mass ratio $m^*=2.0$, reduced velocity $U_r=2{\sim}15$ and damping ratio ${\zeta}=0$. Cylinder vibration responses are dependent on $U_r$ and classified into five regimes, i.e. Regime I ($U_r{\leq}3.2$), Regime II ($3.2<U_r{\leq}5.0$), Regime III ($5.0<U_r{\leq}6.4$), Regime IV ($6.4<U_r{\leq}9.2$) and Regime V ($U_r>9.2$). Different facets of vibration amplitude, hydrodynamic forces, wake patterns and displacement spectra are extracted and presented in detail for each regime.

• Bulletin of the Korean Chemical Society
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• v.28 no.8
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• pp.1261-1264
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• 2007

Bioassay-directed fractionations of the seed extracts of Trichosanthes kirilowii, have resulted in the isolation of two new compounds, 2-(4-hydroxy-3-methoxyphenyl)-3-(2-hydroxy-5-methoxyphenyl)-3-oxo-1-propanol (2) and isoetin 5'-methyl ether (5,7,2',4'-tetrahydroxy-5'-methoxyflavone) (3), together with two known compounds, 7-hydroxychromone (1) and 5,7,4'-trihydroxy-3',5'-dimethoxyflavone (tricin, 4). Their structures were characterized by spectroscopic analysis such as 2D-NMR, HRTOFMS, and UV. Compound 3 showed cytotoxicity against human lung cancer cell line A549, human skin melanoma SK-Mel-2, and mouse melanoma B16F1, with IC50 of 0.92, 8.0, and 7.23 μg/mL, respectively.

• The KIPS Transactions:PartD
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• v.11D no.2
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• pp.453-460
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• 2004

In this thesis, remote conveyor control and monitoring system is designed and Implemented for shoes production process based on Lego prototyping mechanism by using the I/O interface control board for the ISA Interface control board. A conveyor server for real time profess control is implemented based on RTLinux(Real-Time Linux) so that users deride priority of work. And device driver is implemented bated on the RTLinux. Through this system, real-time Client/server monitoring environments Is implemented and tested. And the JMF(Java Media Framework) based monitoring system was implemented and the total processing status war monitored.