• Carbon letters
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• v.14 no.1
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• pp.27-33
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• 2013

An increase in population initiating rapid industrialization was found to consequently increase the effluents and domestic wastewater into the aquatic ecosystem. In this research the potentialities of Sambucus nigra L. (SNL) plant in the remediation of water, contaminated with methylene blue (MB), a basic dye were investigated. SNL was chemically impregnated with $KHCO_3$. Operating variables studied were pH, amount of adsorbent and contact time. In general, pH did not have any significant effect on colour removal and the highest adsorption capacity was obtained in 0.035 g MB/g-activated carbon. The Langmuir, Freundlich, Temkin and Dubinin-Radushkevich adsorption models were applied to describe the equilibrium isotherms. The adsorption isotherm data were fitted to the Temkin isotherm. The mass transfer property of the sorption process was studied using Lagergren pseudo-first-order and chemisorption pseudo-second-order kinetic models. The sorption process obeyed the pseudo-second-order kinetic model. The surface area, pores volume and diameter were assessed by the Brunauer-Emmett-Teller and Barrett-Joyner-Halenda methods. The results were compared to those from activated carbon (Merck) and an actual sample. The results indicate that SNL can be employed as a natural and eco-friendly adsorbent material for the removal of dye MB from aqueous solutions.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1997.10a
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• pp.564-567
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• 1997

In the design of structure the forces acting on the structure are important parameter for noise and vibration control. However, in the complex structure, the forces at the injection point on the structure cannot be measured directly. Thus it is necessary to find out indirect force evaluation method. In this paper forces have been measured with in-situ vibration responses and system information. Three existing techniques of indirect force measurement, viz. direct inverse, principal component analysis and regularization have been compared. It has been shown that multi-vibration responses are essential for the precise estimation of the forces. To satisfy those conditions, Rotary compressor is adopted as test sample, because it is very difficult to measure the injection forces from internal excitation to shell. It has also been obtained that relatively higher force is transmitted though three welding paths to the compressor shell. It shows a good agreement between direct and indirect force evaluation with curvature shell and plate and is investigated the possibility of force evaluation of rotary compressor as a complex structure.

• Smart Structures and Systems
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• v.26 no.1
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• pp.63-75
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• 2020

Substructure pseudo-dynamic hybrid simulation (SPDHS) combining the advantages of physical experiments and numerical simulation has become an important testing method for evaluating the dynamic responses of structures. Various parameter identification methods have been proposed for online model updating. However, if there is large model gap between the assumed numerical models and the real models, the parameter identification methods will cause large prediction errors. This study presents an ANN (artificial neural network) method based on forgetting factor. During the SPDHS of model updating, a dynamic sample window is formed in each loading step with forgetting factor to keep balance between the new samples and historical ones. The effectiveness and anti-noise ability of this method are evaluated by numerical analysis of a six-story frame structure with BRBs (Buckling Restrained Brace). One BRB is simulated in OpenFresco as the experimental substructure, while the rest is modeled in MATLAB. The results show that ANN is able to present more hysteresis behaviors that do not exist in the initial assumed numerical models. It is demonstrated that the proposed method has good adaptability and prediction accuracy of restoring force even under different loading histories.

• The Korean Journal of Ecology
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• v.13 no.2
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• pp.143-148
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• 1990

During the autumn of 1985, the stem cortex of Salix pseudo-lasiogyne on the street sides in Seoul city was collected by a cork borer. The contents of S, Pb and Cd in this sample were determined. The ranges of S, Pb and Cd contents in all the samples were 0.98-3.46$\mu$/g, 0.77-1.81$\mu$g/g and 0.12-0.28$\mu$/g, respectively. Areas which slowed the highest level of S, Pb and Cd in the stem cortex were Yongon-dong, Yongdungp o, Ulchiro, Ch ongnyangni, Shinch on and Suyu-dong, Yongdungp o, Ulchiro and Ch ongnyangni, and Yongon-dong, Yongdungp o and Ch ongnyangni, respectively

• Bulletin of the Korean Chemical Society
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• v.23 no.2
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• pp.291-294
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• 2002

The reactions of triplet oxygen atom with halomethanes as a potential fire extinguisher were studied by a discharge flow-chemiluminescence imaging method. The experiments were carried out under second order conditions. The bimolecular atom-molecule reaction rate constants were determined in terms of the initial rate method. The initial concentration of oxygen atom was also determined under second order rate law instead of the pseudo-first order conditions with $[O(^3P)]_0{\ll}[sample]_0$. The second order conditions were more reliable than pseudo-first order conditions for the determinations of rate constants. The rate constants of the reactions $CF_3I\;+\;O(^3P)$, $CH_3PI\;+\'O(^3P)$, and $CHBrCl_2\;+\;O(^3P)$ were determined to be $5.0\;{\times}\;10^{-12}$ , $1.1\;×\;0^{-11}$ , and $1.9\;{\times}\;10^{-14}cm^3molecule^{-1}s^{-1}$, respectively.

• Near Infrared Analysis
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• v.1 no.2
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• pp.1-8
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• 2000

Using the net analyte signal, hybrid linear analysis was proposed to predict chemical concentration. In this paper, we select a sample from training set and apply orthogonal signal correction to obtain an improved pseudo unit spectrum for hybrid least analysis. using the mean spectrum of a calibration training set, we first show the calibration by hybrid least analysis is effective to the prediction of not only chemical concentrations but also physical property variables. Then, a pseudo unit spectrum from a training set is also tested with and without orthogonal signal correction. We use two data sets, one including five chemical concentrations and the other including ten physical property variables, to compare the performance of partial least squares and modified hybrid least analysis calibration methods. The results show that the hybrid least analysis with a selected training spectrum instead of well-measured pure spectrum still gives good performances, which is a little better than partial least squares.

• Communications for Statistical Applications and Methods
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• v.19 no.6
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• pp.899-904
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• 2012

High-dimensional categorical data models with small sample sizes have not been used extensively in genomic sequences that involve count (or discrete) or purely qualitative responses. A basic task is to identify differentially expressed genes (or positions) among a number of genes. It requires an appropriate test statistics and a corresponding multiple testing procedure so that a multivariate analysis of variance should not be feasible. A family wise error rate(FWER) is not appropriate to test thousands of genes simultaneously in a multiple testing procedure. False discovery rate(FDR) is better than FWER in multiple testing problems. The data from the 2002-2003 SARS epidemic shows that a conventional FDR procedure and a proposed test statistic based on a pseudo-marginal approach with Hamming distance performs better.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.15 no.1
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• pp.1-14
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• 2012

This study was carried out for the purpose of presenting basic data bases for conservation and management measures of Ecological and Scenery Conservation Area in Bongsan. The analysis results of the actual vegetation showed that rate of vegetation cover were composed of 72.3% of Robinia pseudo-acacia Forest, 10.7% of Sorbus alnifoila Forest, and Sorbus alnifoila was founded as a dominant woody plant species in the Core Zone of Bongsan Ecological and Scenery Conservation Area. To investigate the vegetation structure of Sorbus alnifolia Community in Bongsan Ecological and Scenery Conservation Area, twelve $100m^2$ sized plots were set up in Bongsan. According to the classification by TWINSPAN, the communities were divided into the three groups of Sorbus alnifolia Community, Pinus koraiensis Community and Robinia pseudo-acacia Community, To analyze annual diameter growth rate for major tree species, nine sample trees from research plots were measured. Expected ages of Sorbus alnifoila trees were 27~37years, Robinia pseudo-acacia trees were 17~26 years, Pinus koraiensis, Pinus rigida, Prunus sargentii, and Quercus mongolica trees were 27~38 years. As a result, annual diameter growth rates of Robinia pseudo-acacia and Pinus rigida tended to remarkably decreased, Sorbus alnifoila had the wood on inter-specific competition of the woody plant species. Importance values of Sorbus alnifoila in the three layers of Sorbus alnifoila communities were evenly high.

• Bulletin of the Korean Chemical Society
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• v.23 no.7
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• pp.990-994
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• 2002

Hydroxybenzothiophenes, dihydroxy-benzothiophenes, and benzothiophenedione were identified as inter-mediates of benzothiophene (BT) exposed to ultrasonic irradiation. It is proposed that benzothiophene is oxidized by OH radical to sequentially for m hydroxybenzothiophenes, dihydroxybenzothiophenes, and benzothiophenedione. Benzothiophene is decomposed rapidly following pseudo-first-order kinetics in a first-order manner by ultrasonic irradiation in aqueous solution. The toxicity of sonochemically treated solutions was checked by E. coli and a less inhibition in bacterial respiration was observed from the 120-min treated benzothiophene sample than from the untreated benzothiophene sample. Also evolution of carbon dioxide and sulfite was observed during ultrasonic reaction. A pathway for ultrasonic decomposition of benzothiophene in aqueous solution is proposed.

• The Bulletin of The Korean Astronomical Society
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• v.37 no.1
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• pp.46.2-46.2
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• 2012

The black hole mass-stellar velocity dispersion ($M_{BH}-{\sigma}_*$) relation observed in the present-day universe has motivated numerous studies on the black hole-galaxy co-evolution. It is crucial to define the$M_{BH}-{\sigma}_*$ local active galaxies since cosmic evolution of the correlations is calibrated based on the local relation. However, stellar velocity dispersion is difficult to measure in active galaxies due to much higher AGN continuum than stellar pseudo-continuum, resulting in a small sample with reliable velocity dispersion measurements for studying the AGN $M_{BH}-{\sigma}_*$ relation. To increase the sample size and improve the measurements, we obtained high S/N near-IR spectra for 3 local AGNs, i.e., NGC 3227, Akn 120, 3C 390.3, for which reverberation black hole masses are measured, using the TripleSpec at the Palomar 5-m Telescope. By investigating aperture effect and correcting for rotation component, we determine the luminosity-weighted ${\sigma}_*$, based on the spatially resolved kinematics and compare them with optical measurements from literature. Combining our new measurements with literature data, we present an improved $M_{BH}-{\sigma}_*$ relation for the enlarged sample of reverberation-mapped AGNs.