• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
• /
• 2000.04a
• /
• pp.23-28
• /
• 2000

The Green integral equation for the calculation of the forward-speed time-harmonic radiation-diffraction potentials IS derived. The forward-speed Green function presented by Brard is used and the correct free surface boundary condition for the Green function is imposed. The cause of the mistakes in the existing Green integral equation is also pointed out.

• Journal of Ocean Engineering and Technology
• /
• v.11 no.2
• /
• pp.91-99
• /
• 1997

This paper presents theoretical formulations and numerical computations for predicting first-and second-order hydrodynamic force on a ship advvancing in waves. The theoretical formulation leads to linearized radiation and diffration problems solving the three-dimensional Green function integral equations over the mean wetted body surface. Green function representing a translating and pulsating source potantial for infinite water depth is used. In order to solve integral equations for three dimentional flows using Green function efficiently, the Hoff's method is adopted for numerical calculation of the Green function. Based on the first-order solution, the mean seconder-order forces and moments are obtained by directly integrating second-order pressure over the mean wetted body surface. The calculated items are carried out for analyzing the seakeeping characteristics of Series 60. The calculated items are hydrodynamic coefficients, wave exciting forces, frequency response functions and addd resistance in waves.

• Journal of the Chungcheong Mathematical Society
• /
• v.11 no.1
• /
• pp.163-172
• /
• 1998

In this paper, we will study properties of the Green's potential for the Green's function of B which is defined in [8]. In particular, we will investigate boundary behavior of some functions related with Green's function within tangential approach regions that were used in [4].

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.5 no.5
• /
• pp.1001-1010
• /
• 2001

In TLM method, Discrete Green's function ABC have been used when improved the exactness of analyzing in wide frequency band. But this technology has a complicated process to apply absorbing boundary, which means it needs additional numerical analyzing process to obtain discrete Green's function data. so, In this paper, we propose new Green's absorbing layer for simple process to apply absorbing boundary. newly proposed Green's absorbing layer is produced by applying of loss operation, loading discrete Green's function with attenuation. A state of optimum absorbing would be obtained by relation between increasing rate of loss, attenuation constant and length of green's absorbing layer. and then Analysts of waveguide BPF is carried out using Green's absorbing layer within state of optimum absorbing, then this result is in corrective agreement with the result applying traditional discrete Green's function ABC.

• Journal of the Korean Society of Manufacturing Technology Engineers
• /
• v.24 no.5
• /
• pp.535-540
• /
• 2015

We propose an enhanced Green's function approach to predict thermal stresses by considering temperature-dependent material properties. We introduce three correction factors for the maximum stress, the time taken to reach maximum stress, and the time required to attain steady state based on the Green's function results for each temperature. The proposed approach considers temperature-dependent material properties using correction factors, which are defined as polynomial expressions with respect to temperatures based on Green's functions, that we obtain from finite-element (FE) analyses at each temperature. We verify the proposed approach by performing detailed FE analyses on thermal transients. The Green's functions predicted by the proposed approach are in good agreement with those obtained from FE analyses for all temperatures. Moreover, the thermal stresses predicted using the proposed approach are also in good agreement with the FE results, and the proposed approach provides better predictions than the conventional Green's function approach using constant, time-independent material properties.

• Earthquakes and Structures
• /
• v.3 no.3_4
• /
• pp.507-518
• /
• 2012

It is now widely accepted that the resulting displacement field within elastic, inhomogeneous, anisotropic solids subjected to equipartitioned, uniform illumination from uncorrelated sources, has intensities that follow diffusion-like equations. Typically, coda waves are invoked to illustrate this concept. These waves arrive later as a consequence of multiple scattering and appear at "the tail" (coda, in Latin) of seismograms and are usually considered an example of diffuse field. It has been demonstrated that the average correlations of motions within a diffuse field, in frequency domain, is proportional to the imaginary part of Green's function tensor. If only one station is available, the average autocorrelation is equal to the average squared amplitudes or the average power spectrum and this gives the Green's function at the source itself. Several works address this point from theoretical and experimental point of view. However, a complete and explicit analytical description is lacking. In this work we study analytically some properties of the Green's function, specifically the imaginary part of Green's function for 2D antiplane problems. This choice is guided by the fact that these scalar problems have a closed analytical solution (Kausel 2006). We assume the diffusiveness of the field and explore its analytical consequences.

• Proceedings of the Korean Vacuum Society Conference
• /
• 2009.08a
• /
• pp.142-142
• /
• 2009

• Journal of electromagnetic engineering and science
• /
• v.1 no.1
• /
• pp.54-59
• /
• 2001

The dyadic Green`s function for an unbounded anisotropic medium is treated analytically in the Fourier domain. The Green`s function, which is expressed as a triple Fourier integral, can be next reduced to a double integral by performing the integral, by performing the integration over the longitudinal Fourier variable or the transverse Fourier variable. The singular behavior of Green`s is discussed for the general anisotropic case.

• Journal of the Korean Institute of Landscape Architecture
• /
• v.35 no.2 s.121
• /
• pp.81-90
• /
• 2007

This study used the functions for public benefits as a standard for evaluating Green Tourism. By referring to the existing literature, the "function of building emotion", the "function of providing a natural environment", the "function of preserving traditional cultures", and the "function of maintaining the local community" have been selected as the measuring variables. Detailed sub-variables of each function were prepared to examine and analyze the recognition of these are the part of Green Tourists. The Green Tourists of Yangsuri in Yangpyeong, Sinnonri in Yangpyeong, and Jurokri in Yeoju participated in the survey for which 13 variables were used as measurement. The results are as follows: First, Green Tourists recognize farm villages as places for rest and relaxation and they laid great importance on the function of providing access to the natural environment. Secondly, out of the 13 measurement variables, "beautiful scenery in farm village", "making a contribution to village income", and "trust in agricultural products" greatly influenced the overall evaluation of Green Tourism. Thirdly, regarding the relationship between the functions for public benefits and Green Tourism, it was found that "facilities and activities for experiencing farming", "facilities for rest", and "beautiful scenery in farm villages" are closely related to building the emotion experienced in these villages, and that "cultivating environmentally-friendly agricultural products" and "beautiful scenery in farm village" are closely related to the function of providing access to the natural environment.

• Journal of the Korean Institute of Landscape Architecture International Edition
• /
• no.2
• /
• pp.88-93
• /
• 2004

This research aims to grasp the basic knowledge of green belt, which exerts far-reaching effects upon safety, by comparing the revelation of the green belt of the two cities-Japan and China. In result, features of both countries were clarified. The green belt of Japan emphasizes on the function during emergency cases such as natural disasters, while the green belt in China, stresses its' function toward social safety in usual status, such as crimes, accidents or environmental pollution. Also, the function of the green space at normal situations has many in common between these two countries; however, the concepts differ according to geological or social system.