• Journal of Welding and Joining
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• v.8 no.3
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• pp.79-88
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• 1990

Welded joint often contains soft or softened regions such as the HAZ of TMCP steel welded with high heat input. In this study, the equivalent yield strength of plate structure containing softened region was predicted by FEM analysis, and its incremental behavior was explained with the results of the analysis. The calculated results of yield strength indicated the following for the plate structures. 1) As the softened region starts to yield, shear stress begins to build up along the boundary between base metal and softened region. This results in multi-axial stress condition which gives restraint on the softened region. 2) Restraint effect has a significant influence on the distribution of the shear stress, the nominal stress, and the strain. 3) The yielding behavior of softened region becomes the same as that of base metal when both ratios of length to width and thickness to width of softened region are larger than 30 and 13 respectively.

• Cartoon and Animation Studies
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• s.17
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• pp.163-173
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• 2009

The reactivation for Art & Culture Content Space in Gangwon province need new turning point according to new approach with internal and external change. That should be established in sustainable possibility model with preexisted natural advantage instead of economical depression and global warming of in these days. That is not a choice to get a successful construction of art & culture content space in Gangwon province. Throughout of reactivation of art & culture content space in Gangwon province, this proposal should go on with diversity of culture and concrete art & culture educational program absolutely to get a goal in regional economical success and social good influence. Already Yeongwol region had lots of art & cultural spaces and developmental strategy compared with other regions in decade. In these points, I choose this region and would like to research Yeongwol region in limit. Thus I would examine and study about art & culture content space in Yeongwol region. And I will concretely suggest that this proposal is composed with economical creating employment and incoming. The reactivation for Art &Culture Content Space in Yeongwol will build up social and cultural influences to this region to get a new modern cultural images and improvement of common life of regional people by and large. In the way of the process to globalization, this reactivation project for Art &Culture Content Space in Yeongwol should go on the base of regional culture background as a mean of glocalization paradigm strategically. Ahead of developing model for globalization in macroscopic view point, we have to research the demend of reginal situation of cultural content and build up its own strength points. Because Art & Culture Content Space in Yeongwol is the place of people in Yeongwol directly as itself. And managing plans of reactivation of art & culture content space in Yeongwol should build up with diversity of culture and environmental circumstances.

• Journal of Radiation Protection and Research
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• v.9 no.1
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• pp.19-25
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• 1984

There is not yet an universal method of electron dosimetry. The Authors measured dose distributions of the electron beams from Clinac-18 by means of silicon detector connected to X-Y recorder, and compared them in water phantom with dose distributions measured by film and ion chamber, both inserted in polystyrene phantom. The results are as followings, 1. Dose in build-up region increased with the field size for all energy, and depth dose profiles of $6{\sim}12MeV$ beam under the depth of maximum dose were independent of field size, but those of 15 and 18 MeV beam were dependent on the field size. 2. The widths of penumbra by semiconductor detector were narrower than those by film for same energy beam. 3. Depth dose profiles by three different dosimeter did not coincide each other. In the build-up region, dose by semiconductor detector was lower than that by any other dosimeter.

• Ocean and Polar Research
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• v.25 no.1
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• pp.63-74
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• 2003

The build-up of the heat field in shallow coastal water due to a point source has been investigated using an analytical solution of a time-integral form derived by extending the solutions by Holley(1969) and also presented in Harleman (1971). The uniform water depth is assumed with non-isotropic turbulent dispersion. The alongshore-flow is assumed to be uni-directional, spatially uniform and oscillatory. Due to the presence of the oscillatory alongshore-flow, the heat build-up occurs in an oscillatory manner, and the excess temperature thereby fluctuates in that course and even in the quasi-steady state. A series of calculations reveal that proper choices of the decay coefficient as well as dispersion coefficients are critical to the reliable prediction of the excess temperature field. The dispersion coefficients determine the absolute values of the excess temperature and characterize the shoreline profile, particularly within the tidal excursion distance, while the decay coefficient determines the absolute value of the excess temperature and the convergence rate to that of the quasi-steady state. Within the e-folding time scale $1/k_d$ (where $k_d$ is the heat decay coefficient), heat build-up occurs more than 90% of the quasi-steady state values in a region within a tidal excursion distance (L), while occurs increasingly less the farther we go to the downstream direction (about 80% at 1.25L, and 70% at 1.5L). Calculations with onshore and offshore discharges indicate that thermal spreading in the direction of the shoreline is reduced as the shoreline constraint which controls the lateral mixing is reduced. The importance of collecting long-term records of in situ meteorological conditions and clarifying the definition of the heat loss coefficient is addressed. Interactive use of analytical and numerical modeling is recommended as a desirable way to obtain a reliable estimate of the far-field excess temperature along with extensive field measurements.

• Journal of Forest and Environmental Science
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• v.9 no.1
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• pp.57-66
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• 1993

The purpose of this study is to offer detailed topographic information for substantially selecting the yarding machine for mechanized yarding operations, classifying the forest site by cluster analysis and principal component analysis, and investigating simultaneously the variables which give much influence on the classification of forest site in forestry build-up region (21, 477ha) of Chunchon Gun, Kwangweon Do. Ten topographic variables were used for the analysis. The results of study were as follows : 1) Gosung region (2, 252ha) was classified into hilly terrain (57%) and steep terrain (43%) and required the tractor prehauling system for the former one and the medium skyline system for latter one, respectively. 2) 65% of Gajung region (2,306ha) and 67% of Kwangpan region (2, 627ha) were classified into steep terrain fitted for the medium skyline system and the portion of both region showed the hilly terrain for the tractor prehauling system. 3) Jiam region (4, 591ha), consisted only of steep terrain, required the medium skyline system. 4) Gunja region (3, 400ha), Sudong region (3, 984ha) and Sinpo region (2, 340ha) were classified into steep terrain, requiring the medium skyline system, with 85%, 75%, and 75%, respectively.

• Journal of Radiation Protection and Research
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• v.43 no.2
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• pp.75-84
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• 2018

Background: Gamma-ray spectrometry helps in radiation shielding problems and different applications of radioisotopes. Experimental arrangements including broad beam geometries are widely used. The aim is to investigate and evaluate the ${\gamma}-ray$ spectra via attenuation by environmental materials. Materials and Methods: The photo peak to nominated parts in the ${\gamma}-ray$ spectra and the attenuation coefficients ${\mu}_b/{\rho}$ from broad beam geometries are measured for the materials water, soil, sand and cement at the energies 0.662, 1.25, and 1.332 MeV with a $3{^{\prime}^{\prime}}{\times}3{^{\prime}^{\prime}}$ NaI(Tl) detector. Results and Discussion: The ${\gamma}-ray$ spectra vary according to changes in the effective atomic number $Z_{eff}$ of the attenuator, the photon energy and the solid angle. The peak to total ratios are the most sensitive parts to variations in the experimental conditions and overturn in the region 0.663 MeV to 1.332 MeV. This is indicated as inversion trend. The results are discussed in view of $Z_{eff}$ and the experimental conditions. The intensity build-up is larger at the lower energy and larger scattering angles in agreement with Klein-Nishina formula and other results. The build-up factor B is$${\sim_=}$$1 at high ${\gamma}-energies$ and small scattering angles. Conclusion: The sensitivity to material characteristics decrease gradually from peak: to total, to Compton valley, to Compton plateau ratios. Rigorous collimation is necessary at small energies. Cement, of the largest $Z_{eff}$, is characterized by the maximum broad beam mass attenuation coefficients ${\mu}_b/{\rho}$. The obtained results provide information to decide for the suitable experimental set-up based on aim of the work.

• The Journal of Korean Society for Radiation Therapy
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• v.7 no.1
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• pp.176-184
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• 1995

It is very useful benefits to use the megavoltage photon beams in deep site tumor radiotherapy for skin sparing effects. But, In some cases of head and mock tumors, it is often necessary to use spoiler for rapid buildup on skin region. A spoiler with tissue equivalent material to be moved between the patients and the collimator can increase or control the skin dose and buildup region due to position and thickness of the spoiler was measured. Then, the effect of spoiler on skin dose and build up region in protruded tumor of head and neck was evaluated quantitatively. The measurements were abtained with PTW 2334 chamber (Markus type) on a polystylene phantom for 6MV x-ray from an accelerator.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.21 no.12
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• pp.1576-1585
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• 1997

The microexplosive combustion of a slurry droplet was investigated experimentally. The microexplosion has been approximately considered to be caused by pressure build-up in the shell and to be promoted by heterogeneous nucleation of liquid carrier, which is due to the suppression of evaporation and subsequent superheating of liquid carrier. To closely investigate the pressure build-up and the heterogeneous nucleation, the experiments were conducted in an electric combustor, of which temperature was controllable (400 K-900 K). And the effects of two aligned droplets on the interactive combustion and microexplosion were found in a hot post region of a flat flame burner. Transient internal temperature distributions for slurry droplets were measured. And the shell formation and the microexplosion of suspended A1/JP-8 and Al/n-heptane slurry droplets were examined with various surfactant concentrations (0.5-5 wt%) and solid loadings (10-50 wt.%). The microexplosion time of binary array of droplets was found to be less than that of the isolated droplet due to radiative interaction between droplets.

• 제어로봇시스템학회:학술대회논문집
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• 1997.10a
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• pp.261-264
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• 1997

A contactless eddy current type braking system is developed to take advantages of the recent brake system which uses hydraulic force can show high efficiency in a certain velocity region, but not in a high velocity region, and has initial response delay time and pressure build-up time which make stopping distance longer. These are the limits of mechanical brake system of a contact type, which makes a concept brake system required. So, in this paper, the contactless brake system .of a inductive current type is chosen instead of hydraulic brake system. This brake system can be used almost forever for being no wear and contributed to lightening weight of a vehicle. Besides, the contactless brake system can be used as that of electric or solar car with anti-lock brake system. The analysis of induced electromotive force and braking torque obtained with theoretical approximate model, the design of a braking system and a nonlinear controller, and the results of simulation of the ABS, experiment are included.

• The Bulletin of The Korean Astronomical Society
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• v.36 no.2
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• pp.56.1-56.1
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• 2011

We investigate the hydrodynamics of gas clouds in the central few hundred parsecs of the Galaxy. Non-axisymmetry (elongation) of the Galactic bulge can form a reservoir of dense molecular clouds at around two hundred parsecs from the center through the X1-X2 orbit transfer, and the star formation that has been sustained for the lifetime of the galaxy can build up a nuclear bulge there. If the nuclear bulge is elongated, this again can transport the gas there down to the central few parsecs region. We perform a series of 3-D hydrodynamic simulations that consider a potential for this "nested bar", cooling/heating, star formation and supernova feedback, and estimate the efficiency of the gas inflow down to the central parsec region.