• 한국전산유체공학회:학술대회논문집
• /
• 2004.03a
• /
• pp.71-76
• /
• 2004

An extension of our recently developed locally linear reconstruction scheme to 2 dimensional incompressible flow solver is presented. The solver is based on a semi-implicit fractional step method in which the convective term is discretized by Adams-Bashforth method and the diffusion term by Crank-Nicolson method. Several numerical examples are tested to demonstrate the mesh type independent accuracy of the solver, which include decaying vortex flow, square cavity flow, and flow around a circular cylinder. The above examples are solved on quadrilateral or hybrid meshes. For all numerical examples, we obtained reasonable results.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
• /
• v.23 no.6
• /
• pp.491-496
• /
• 2010

The relaxation behavior of aligned electric dipoles in a mixed polymer of P2ANS with P(VDF-TrFE) is studied with optical second harmonic generation (SHG). In this work, a macroscopic noncentrosymmetry of the spin coated film was achieved by an electrical poling. The relaxation of induced polar order of nonlinear optic(NLO) chromophores after poling leads to an insufficient long-term stability of NLO properties. In this work, we develop a new technique to suppress such kind of dipole relaxation in a poled polymer. We found that the poled dipoles in a NLO polymer were effectively immobilized by the internal electric field created by a thermally annealed ferroelectric polymer. The long-term stability in a mixed system of NLO polymer/ferroelectric polymer was successively accomplished by a series of thermal treatments applied to the mixed polymer system at a temperature of $140^{\circ}C$ for at least 1hour after poling.

• 제어로봇시스템학회:학술대회논문집
• /
• 1996.10b
• /
• pp.387-390
• /
• 1996

In this paper, A new PI-type reaching law for variable structure control is proposed to alleviate the chattering and improve the robustness properties in the presence of matched uncertainty. The proposed reaching law consists of a proportional term and an integral term. And the dynamics of switching function can easily be specified by using the second-order system analysis method. And also the proposed scheme has the advantages of alleviating the chattering than Gao's one and reducing the influence of uncertainties by band pass filter characteristic. The efficiency of the proposed method has been demonstrated by simulations for Dutch Roll damping in a light aircraft.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.30 no.2 s.245
• /
• pp.171-178
• /
• 2006

Experimental and theoretical study of the non-planar response motions of a circular cantilever beam subject to base harmonic excitation has been presented in this paper work. Theoretical research is conducted using two non-linear coupled integral-differential equations of motion. These equations contain cubic linearities due do curvature term and inertial term. A combination of the Galerkin procedure and the method of multiple scales are used to construct a first-order uniform expansion for the case of one-to-one resonance. The results show that the non-linear geometric terms are very important for the low-frequency modes of the first and second mode. The non-linear inertia terms are also important for the high-frequency modes. We present the quantitative and qualitative results for non-planar motions of the dynamic behavior.

• Journal of the Korean Mathematical Society
• /
• v.44 no.3
• /
• pp.627-645
• /
• 2007

We investigate the eigenvalues of the semi-circulant preconditioned matrix for the finite difference scheme corresponding to the second-order elliptic operator with the variable coefficients given by $L_vu\;:=-{\Delta}u+a(x,\;y)u_x+b(x,\;y)u_y+d(x,\;y)u$, where a and b are continuously differentiable functions and d is a positive bounded function. The semi-circulant preconditioning operator $L_cu$ is constructed by using the leading term of $L_vu$ plus the constant reaction term such that $L_cu\;:=-{\Delta}u+d_cu$. Using the field of values arguments, we show that the eigenvalues of the preconditioned matrix are clustered at some number. Some numerical evidences are also provided.

• The Korean Journal of Food And Nutrition
• /
• v.4 no.1
• /
• pp.9-20
• /
• 1991

The purpose of this study Is to prove the propriety of prolongation in educational term of department of food and nutrition at junior college in Korea in order to Improve the quality of dietitian by giving substantial education. The prolongation of educational term from two to three years is necessary to cultivate a more excellent dietitian because of the following three reasons. First, the freshmen in junior colleges are poor in basic scholastic ability which is needed for the study of nutrition science. Second, many new subjects which will support the new rollers of dietitian, in accordance with social changes, should be supplemented In curriculum. Third, the subject of spot-practice for dietitian should be established as a regular course in curriculum.

• Journal of Ocean Engineering and Technology
• /
• v.22 no.2
• /
• pp.7-12
• /
• 2008

A far field solution of the slowly varying force on an offshore structure by gravity ocean waves was shown as a function of the reflection and transmission of the body disturbed waves. The solution was obtained from the conservation of the momentum flux, which simply describes various wave forces, while making it unnecessary to compute complicated integration over a control surface. The solution was based on the assumption that the frequency difference of the bichromatic incident waves is small and its second order term is negligible. The final solution is expressed in term of the reflection and transmission waves, i.e. their amplitudes and phase angles. Consequently, it shows that not only the amplitudes but also the phase differences make critical contributions to the slowly varying force. In a limiting case, the slowly varying force solution gives the one of the mean drift force, which is only dependent on the reflection wave amplitude. An approximation is also suggested in a case where only the mean drift force information is available.

• Korean Journal of Social Welfare
• /
• v.44
• /
• pp.178-208
• /
• 2001

This study concerns the understanding of 'social exclusion' which is getting poplular in Europe as the new term or paradigm in order to resolve poverty problem. As case study on the France, the purpose of this study is to extract the consideration of welfare policy and suggestions as to us. In order to understand comprehensively the concept 'social exclusion' and the situation of the France, this study analyzes the existing researches on its concept and tries to realize a comparative study. Thus, this study indicates that the France is the state which has taken the most interest in 'social exclusion'. The second parti of this study concerns the change of the concept 'social exclusion' and its policies in the France. The concept 'social exclusion' which has used in the 1960's, has settled as the term of policies in the 1980's, thanks to seriousness of poverty and unemployment problem and change of social consciousness (opinion). As policy on the 'social exclusion', there are Revenu minimum d'insertion of the 1988 and law on the social exclusion of the 1998. Through analysis of policies on the 'social exclusion' in the France, we can get the following consideration of welfare policy and suggestions: on the macro level, the necessity to establish the comprehensive perspective on the poverty problem, invention and development of the term as regard to social new problem; on the micro lever, planning of welfare program according to clients needs, importance of perpetual assessing of the existing welfare program and institutions, the institutional establishment of 'reserve budget', the application of decentralization principle and the active participation of the private sector in order to promote the effectiveness and the efficiency of the program and institutions.

• Asia Marketing Journal
• /
• v.15 no.1
• /
• pp.23-42
• /
• 2013

To overcome the profitability challenge these days, many global banks are increasingly focusing on cost efficiency through more efficient banking processes, such as online and mobile banking, whereas a number of other banks choose to differentiate their services for retaining and attracting the most valuable customer segment (Deloitte, 2011). While global banks in the retail banking industry are adopting either of these two business models as a strategic choice for their long-term growth, KB Kookmin Bank, one of the leading retail banks in South Korea, has begun to operate 'KB Rockstar' as a strategic channel, particularly designed to target college students in the youth market. The new marketing strategy has resulted in a positive impact on its brand image in customers' perception as well as a drastic increase in the number of youth customers. In this study, we analyze the case of 'KB Rockstar' and summarize the key factors for its success from a marketing perspective. First, 'KB Rockstar' is not simply a good channel strategy, but an innovative marketing strategy that aligns place, product and promotion together in order to create a synergy effect, resulting in the successful implementation of the bank's targeting strategy. Second, the strategy effectively establishes 'KB Rockstar' as a brand targeted to youth customers while also competently strengthening the image of the corporate brand, KB Kookmin Bank. The skillful implementation of organically combined marketing mix strategies has enabled the successful launch of the bank's sub-brand. Third, the strategy considers a retail bank branch as not only the place that makes sales transactions in order to generate short-term profits, but also the place that builds a long-term relationship with customers in order to maximize their lifetime values in the long run.

• Journal of the Korean Chemical Society
• /
• v.45 no.1
• /
• pp.14-24
• /
• 2001

In order to study the long-term change of water quality, water analysis for 9 items was conducted at 13 sites surrounding the Kumho river system for 18 times from September 1993 to August 1999. Analytical items for the study of water quality are as follows; water temperature, pH, BOD, COD, DO, SS, electrical conductivity, oil and grease, ABS and phenol. The six year term was divided into Part I(second study) and Part Ⅱ(third study), which covers the term from September 1993 to August 1996 and the term from September 1996 to August 1999, respectively. The mean values obtained for three years for water temperature, pH, BOD, COD, DO, SS, electrical conductivity, oil and grease, ABS and phenol for the Part I period showed 18.4$^{\circ}C$, 7.9, 4.88 ppm, 9.66 ppm, 9.0 ppm, 618.0 umho/cm, 6.9 ppm, 2.63 ppm, 3.57 ppm and 0.98 ppm, respectively. The mean values obtained for water temperature, pH, BOD, COD, DO, SS, electrical conductivity, oil and grease, ABS and phenol for the Part Ⅱ period showed 18.0$^{\circ}C$, 8.0, 2.86 ppm, 7.40 ppm, 8.94 ppm, 541.0 umho/cm, 6.0 ppm, 5.43 ppm, 0.94 ppm and 0.01 ppm respectively. The values of BOD, COD, SS, electrical conductivity, ABS and phenol in the second period were found to be decreased by 1/1.71, 1/1.31, 1/4.15, 1/3.80 and 1/98, respectively. The values of water temperature, pH and DO were nearly constant. However, the concentrations of oil and grease were found to be increased about 2.06 times in the second period.