트랜섬 선미를 가지는 선형의 비선형 포텐셜 유동해석

Journal of Soil and Groundwater Environment, 2011

Mercury accumulates in biota mainly as methylmercury. In nature, methylmercury shows high affinity to organic matter and CH 3 Hg + -organic matter complexation affects the mobility and bioavailabiity of methylmercury. In this study, we examined the methylmercury binding sites in an aquatic humic acid as affected by the pH condition using Hg L III -edge extended X-ray absorption fine structure (EXAFS). We evaluated methylmercury binding humic ligands using methylmercury-thiol, methylmerury-carboxyl, and methylmercury-amine complexation models. When CH 3 Hg + -to-humic reduced sulfur ratio is 0.3, we found that most of CH 3 Hg + binds to thiol ligands at pH 5 and 7. At pH 7, however, some carboxyl or amine ligand contribution is observed, unlike at pH 5 where CH 3 Hg + almost exclusively binds to thiol ligands. The carboxyl or amine ligand contribution may indicate that some types of thiol ligands in the natural organic matter have relatively low complexation constants or acid dissociation constants compared to those of some carboxyl or amine ligands. Analysis results indicate that ~0.2 fraction of methylmercury binds to amine or carboxyl ligands and ~0.8 to thiol ligands at pH 7.

Journal of Control, Automation and Systems Engineering, 2006

Journal of Ocean Engineering and Technology, 2012

In this paper, a Bayesian classifier based on PCA (principle component analysis) is proposed to classify underwater transient signals using 16 th order LPC (linear predictive coding) coefficients as feature vector. The proposed classifier is composed of two steps. The mechanical signals were separated from biological signals in the first step, and then each type of the mechanical signal was recognized in the second step. Three biological transient signals and two mechanical signals were used to conduct experiments. The classification ratios for the feature vectors of biological signals and mechanical signals were 94.75% and 97.23%, respectively, when all 16 order LPC vector were used. In order to determine the effect of underwater noise on the classification performance, underwater ambient noise was added to the test signals and the classification ratio according to SNR (signal-to-noise ratio) was compared by changing dimension of feature vector using PCA. The classification ratios of the biological and mechanical signals under ocean ambient noise at 10dB SNR, were 0.51% and 100% respectively. However, the ratios were changed to 53.07% and 83.14% when the dimension of feature vector was converted to three by applying PCA. For correct, classification, it is required SNR over 10 dB for three dimension feature vector and over 30dB SNR for seven dimension feature vector under ocean ambient noise environment.

Clean Technology, 2014

General household vacuum cleaners consist of dust collector, pre filter, motor and exhaust filter, and the filtered clean air is discharged to the atmosphere. By using the CFD methods, we estimated the internal flow in two types of commercial cyclone vacuum cleaners to evaluate the dust collection performance. From the analysis, it was known that the number of revolution had higher values in cyclone cone region. CFD analysis in a specific showed non-uniform velocity distribution at outlet, which results in the deterioration of particle collection performance. In order to improve flow condition, the installation of baffle was proposed and the values of velocity RMS were estimated.

Journal of the Korea institute for structural maintenance and inspection, 2013

Probabilistic nonlinear first ply failure loads of flat composite panels and nonlinear buckling loads of curved composite panels with cutouts are estimated to provide the more reliable main load carrying structure in the renewable energy industry and offshore structures. The response surface method approximates limit state surface to a second order polynomial form of random variables with the results of deterministic finite element analyses at given sampling design points. Furthermore, the iterative linear interpolation scheme is used to obtain a more accurate approximation of the limit state surface near the most probable failure point (MPFP). The advanced first order second moment method and the Monte Carlo method are performed on an approximated limit state surface to evaluate the probability of failure. Finally, the sensitivity of the reliability index with respect to transformed random variables is investigated to figure out the main random variables that have an effect on failures.

Transactions of the Korean Society of Mechanical Engineers A, 2013

Journal of Korea Multimedia Society, 2012

Transactions of the Korean Society of Automotive Engineers, 2016

This paper discusses about analyzing in-wheel vehicle's dynamic motion and load torque. Since in-wheel vehicle controls each left and right driving wheels, it is dangerous if vehicle's wheels are not in a cooperative control. First, this study builds the main wheel control logic using PID control theory and evaluates the stability. Using Carsim-Matlab/Simulink, vehicle dynamic motion is simulated in virtual 3D driving road. Through this, in-wheel vehicle's driving performance can be analyzed. The target vehicle is a rear-wheel drive in D-class sedan. Second, by using the first In-wheel vehicle's performance results, it derivate the drive motor's dynamic load torque for applying the dynamometer. Extracted load torque impute to dynamometer's load motor, linear experiment in dynamometer can replicated the 3-D road driving status. Also it, will be able to evaluate the more accurate performance analysis and stability, as a previous step of actual vehicle experiment.

Journal of The Korean Society of Agricultural Engineers, 2012

Accurate modeling rainfall induced landslide and slope stability requires a detailed knowledge of the distribution of material strength characteristics and suction distribution. However, material properties obtained from the drying cycle are still used for infiltration analysis in many cases, even though material properties of wetting cycle are quite different from those of drying cycle due to hydraulic hysteresis and air occlusion. Therefore, the selection of proper material properties such as soil-water retention curve (SWRC) and the hydraulic conductivity function (HCF) reflecting characteristics of wetting cycle and air occlusion is an essential prerequisite in order to simulate the infiltration phenomena and to predict the suction and water content distribution in unsaturated soils. It is concluded that the simulation of infiltration with material properties from the drying cycle did not reasonably match with experimental outputs. Further discussion is made on how to describe the material properties considering air occlusion during wetting cycle over the entire suction range in order to simulate infiltration phenomena.

Journal of Korea Spatial Information Society, 2014

The Triangle Mesh Warping method is suggested and applied in coordinate transformation to world geodetic system in this study. The common points of Uiwang city are used to compare the transformation accuracy of the suggested methods with existing national coordinate transformation methods. As a result, the Triangle Mesh Warping method was satisfied with accuracy criteria for positioning on a map larger than scale 1/1,000 with smaller number of common points and without distortion modeling. Additionally, in case of Guri and Pyeongtaek city that established the World Geodetic System, the suggested method generates the result of transformation accuracy better than 5cm. Based on the test, it was found that the suggested method improves the problem of securing many common points and reduces the problem of mis-match between the transformed data of adjacent areas. Accordingly, for transformation of large-scale topographic map, cadastral map, GIS DB and serial cadastral map to the World Geodetic System, it is judged that the Triangle Mesh Warping would be a good method for economical efficiency and accuracy using by minimum common point.

Journal of the Korea Concrete Institute, 2012

Cement has been traditionally used as a main binding material of high ductile fiber reinforced cementitious composites. The purpose of this paper is to investigate the feasibility of using alkali-activated slag and polyvinyl alcohol (PVA) fibers for manufacturing high ductile fiber reinforced cementless composites. Two mixture proportions with proper flowability and mortar viscosity for easy fiber mixing and uniform fiber dispersion were selected based on alkali activators. Then, the slump flow, compression, uniaxial tension and bending tests were performed on the mixes to evaluate the basic properties of the composites. The cementless composites showed an average slump flow of 465 mm and tensile strain capacity of approximately 2% of due to formation of multiple micro-cracks. Test results demonstrated a feasibility of manufacturing high ductile fiber reinforced composites without using cement.

A paired many-to-many -disjoint path cover (-DPC for short) of a graph is a set of  disjoint paths joining  distinct source-sink pairs in which each vertex of the graph is covered by a path. A two-dimensional  ×  torus is a graph defined as the product of two cycles   and   of length  and  , respectively. In this paper, we deal with an  ×  bipartite torus, even   ≥ , with a single faulty vertex, and present a necessary and sufficient condition for the torus to have a paired many-to-many 2-DPC connecting given two source-sink pairs as follows: Out of the four sources and sinks, exactly one of them has the same color as the faulty vertex. 1. 서 론 상호 연결망(interconnection networks)에서 노드들 사이의 라우팅이나 선형 배열의 임베딩 등과 관련하여 다루는 중요한 문제 중의 하나는 노드가 서로소인 경로 (node-disjoint paths)를 찾는 것이다. 노드가 서로소인 경로는 노드들 사이에 효율적인 데이터 라우팅을 위한 병렬 경로로 사용될 수 있다. 또한 노드가 서로소인 경 로에서 각 경로는 파이프라인 계산에 이용될 수 있다. 상호연결망은 자주 그래프로 모델 되는데, 정점과 에지 는 각각 노드와 통신 링크에 대응한다. 이 논문에서는 노드가 서로소인 경로를 간단히 서로소인 경로라고 부 르기로 한다. 서로...

Journal of the Korean Ceramic Society, 2012

Silicon carbide(SiC) exhibits many unique properties, such as high strength, corrosion resistance, and high temperature stability. In this study, a SiC-fiber web was prepared from polycarbosilane(PCS) solution by employing the electrospinning process. Then, the SiCfiber web was pyrolyzed at 1800 o C in argon atmosphere after it was subjected to a thermal curing. The SiC-fiber web (ground web)/ phenolic resin (resol) composite was fabricated by hot pressing after mixing the SiC-fiber web and the phenolic resin. The SiC-fiber web composition was controlled by changing the fraction of filler (filler/binder = 9:1, 8:2, 7:3, 6:4, 5:5). Thermal conductivity measurement indicates that at the filler content of 60%, the thermal conductivity was highest, at 6.6 W/mK, due to the resulting structure formed by the filler and binder being closed-packed. Finally, the microstructure of the composites of SiC-fiber web/resin was investigated by FE-SEM, EDS, and XRD.

Han'gug jeonsan yuchegong haghoeji, 2015

This paper introduces a computational method for analysis of the 6-DOF motions of a ship in waves using an overset grid technique which consists of inner and outer domains for representing body motions and numerical wave tank, respectively. High order interpolation scheme is employed to increase numerical accuracy over the interface where physical values, such as velocities and pressure, interact between the inner and outer domains. The numerical schemes and algorithm are addressed in the present paper. An application to motion of KCS container carrier in head waves is presented, and the comparison of responses on heave and pitch motions shows good agreement with those of model tests.

Journal of the Korean earth science society, 2007

The first magnetotelluric (MT) transect across the Korean Peninsula was obtained traversing from the East Sea