• Journal of Environmental Science International
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• v.13 no.9
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• pp.835-843
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• 2004

N,N-bis(2-salicylaldehyde)dipropylenetriamine(5- Hsaldipn), N,N-bis( 5-bromosalicyl-aldehyde) dipropylenetriamine (5-Brsaldipn), N,N-bis(5-chlorosalicy laldehyde )dipropylene-triamine(5-Clsaldipn), N,N-bis(2-hydroxy- $5-methoxy-benzaldehyde)dipropylenetriamine(5-OCH_3saldipn)$ and N,N-bis (2-hydroxy-5-nitrobenzaldehyde)dipropylenetriamine $(5-NO_2saldipn)$ were synthesized and characterized by elemental analysis, infrared spectrometry, NMR spectrometry and mass spectrometry. Their proton dissociation constants were determined in 70% dioxane/30% water solution by potentiometric. Stability constants of the complexes between these ligands and the metal ions such as Cu(II), Ni(II) and Zn(II) were measured in dimethyl sulfoxide by a polarographic method. Stability constants for the ligands were in the order of $5-OCH_3$ > 5-H > 5-Br > 5-Cl > $5-NO_2$ saldipn. Enthalpy and entropy changes were obtained in negative values.

• Biotechnology and Bioprocess Engineering:BBE
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• v.11 no.3
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• pp.187-198
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• 2006

The aromatic hydrocarbons (AHs), which include benzene, polycyclic aromatic hydrocarbons, and dioxin, are important chemical and environmental contaminants in industry that usually cause various diseases. Over the years, numerous studies have described and evaluated the adverse health effects induced by AHs. Currently, "Omics" technologies, transcriptomics and proteomics, have been applied in AH toxicity studies. Proteomics has been used to identify molecular mechanisms and biomarkers associated with global chemical toxicity. It could enhance our ability to characterize chemical-induced toxicities and to identify noninvasive biomarkers. The proteomic approach (e.g. 2-dimensional electrophoresis [2-DE]), can be used to observe changes in protein expression during chemical exposure with high sensitivity and specificity. Matrix-assisted laser desorption/ionization-time of flight mass spectrometry (MALDI-TOF MS) and electrospray ionization-quadrupole (ESI-Q)-TOF MS/MS are recognized as the most important protein identification tools. This review describes proteomic technologies and their application in the proteomic analysis of AH toxicity.

• 제어로봇시스템학회:학술대회논문집
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• 2001.10a
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• pp.111.4-111
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• 2001

In this paper, an adaptively tuned dynamic absorber is proposed. The adaptively tuned dynamic absorber is a dynamic absorber whose stiffness is tuned so that the natural frequency of the absorber coincides with the operating or natural frequency estimated by an adaptive algorithm. The feature of this absorber is as follows. It has an electrodynamic device for the stiffness control. Using Lorenz´s force, it changes the stiffness by changing the applied current. The change of stiffness results in the natural frequency shift, because its mass and damping coefficient are fixed. We may reduce the vibration of the overall system by tuning the natural frequency of the dynamic absorber to the resonant frequency of the structure, when the dominant single tone oscilation occurs in the system ...

• 제어로봇시스템학회:학술대회논문집
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• 2002.10a
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• pp.97.2-97
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• 2002

A method for the non-destructive detection of damage using parameterized partial differential equations and Galerkin approximation techniques is presented. This method provides the theoretical and experimental verification of a nondestructive time domain approach to examine structural damage in smart structure. The time histories of the vibration response of structure were used to identify the presence of damage. Damage in a structure causes changes in the physical coefficients of mass density, elastic modulus and damping coefficient. This paper examines the beam-like structures with PVDF sensor and PZT actuator to perform identification of those physical parameters and to detect the...

• 한국전산유체공학회:학술대회논문집
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• 2010.05a
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• pp.122-126
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• 2010

The Rayleigh Plesset based cavitation model(Singhal et al., 2002) is reproduced through a pressure-based finite-volume numerical method using unstructured hexagonal mesh, which is developed by the author. In the process of reproduction, a mass conservation problem by the large density changes associated with phase change, which wasn't mentioned by them, has been exposed. One resolution about it is proposed and then cavitating flow characteristics around a hydrofoil (NACA66) for evaluation of the code are investigated. The computational results are verified by the comparison with the experimental results and show good agreements with them.

• The Korean Journal of Nuclear Medicine
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• v.36 no.1
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• pp.64-73
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• 2002

FDG-PET has potential as an effective, non-invasive tool to measure tumor response to anticancer therapy. The changes in tumor FDG uptake may provide an early, sensitive guide to the clinical and subclinical response of tumors to cancer treatment, as well as functional assessment of residual viable tumor. This may allow the evaluation of subclinical response to anticancer drugs in early clinical trials and improvements in patients management. However, monitoring tumor responses with FDG-PET is still in its infancy. The methods of measurement of FDG uptake are currently diverse and timing with respect to anti cancer therapy variable. Therefore, there is a need for larger-scale trials along with standardized methodology and a collection of reproducibility data. The recent guideline from the European group seems to be the most comprehensive. In future, the combination of morphological and metabolic images may improve the quantitative nature of these measurements by relating tumor viability to total tumor mass. More data on sensitivity and specificity of FDG-PET technique are needed along with continued advancement of PET methodology.

• Ocean Science Journal
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• v.41 no.1
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• pp.31-41
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• 2006

Seasonal changes of abundance of the main phytoplankton groups of species (diatoms, dinoflagellates, chrysophytes, small flagellates and cryptophytes) and a set of environmental parameters were investigated in coastal and pre-estuarine waters of Peter the Great Bay (East/Japan Sea) in May-October of 1998 and 1999. Three periods of mass development were revealed: spring, summer and autumn blooms, with successive change of species. The conditions favourable for each group of species were determined. Driving mechanisms of the succession include nutrients transport through seasonal pycnocline by turbulent mixing, terrestrial nutrients supply by monsoon floods, nutrients supply by upwellings, and light control by the thickness of upper mixed layer. Summer succession could be explained by a simple SST-MLD diagram similar to Pingree S-kh diagram with sea surface temperature as indicator of stratification (S) and mixed layer depth as indicator of light availability (kh).

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.19 no.4
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• pp.363-369
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• 2009

A vibration analysis for a rotating cantilever beam with the tapered cross section is presented in this study. The stiffness changes due to the stretching caused by centrifugal inertia forces when a tapered cantilever beam rotates about the axis perpendicular to its longitudinal axis. When the cross section of cantilever beam are assumed to decrease constantly, the mass and stiffness also change according to the variation of the thickness and width ratio of a tapered cantilever beam. Such phenomena result in variations of natural frequencies and mode shapes. Therefore it is important to the equations of motion in order to be obtained accurate predictions of these variations. The equations of motion of a rotating tapered cantilever beam are derived by using hybrid deformation variable modeling method and numerical results are obtained along with the angular velocity and the thickness and width ratio.

• Journal of the Korean Institute of Telematics and Electronics D
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• v.34D no.12
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• pp.62-67
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• 1997

The optical lithography wit an ArF excimer laser as a light source is expected to be used in the mass production of giga-bit DRAMs which require less than 0.2.mu.m minimum feature size. In this case, the distortion of a patterned image becomes very severe, since the lithography porcess is performed at the resolution limit. Traditionally, the photomask pattern was designed and revised with trial-and-error methods, such as repeated execution of process simulators or actual process experiments which require time and effort. Ths paper describes a program which automatically finds an optimal mask pattern. The program divides the mask plane into cells with same sizes, chooses a cell randomly, changes the transparent/opaque property of the cell, and eventually genrates a mask pattern which produces required image pattern. The program was applied to real DRAM cell patterns to produce mask patterns which genertes image patterns closer to object images than original mask patterns.

• Proceedings of the KSR Conference
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• 2001.10a
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• pp.304-309
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• 2001

Natural frequencies are studied for dynamic analysis of plate girder bridges which are made up about 34% in the existing railway bridges in Korea. In this study, standard plate girder bridges designed by L-22, a standard load type of the railway specification in Korea, are modeled for finite element method analysis. SAP2000n, a commercial finite element method analysis tool, is used for structural analyses and evaluations. Span lengths of Plate girders have 7 types : 6m, 9m, 12m, 15m, 22m, 24m, and 30m. Natural frequencies are considered in mass rations and span lengths and they are compared with a recommendation of UIC 776-1R for alterations, from now on, in train conditions of operation. For changes of natural frequencies in plate girders by damages of structures, Parameter studies are accomplished.