• Journal of Advanced Marine Engineering and Technology
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• v.31 no.6
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• pp.681-686
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• 2007

The flow analysis was made by applying the turbulent models in the scroll volume of centrifugal compressor. The $k-{\varepsilon}.\;k-{\omega}$, Spalart-Allmaras and reynolds stress models are used in which the hybrid grid is applied for the simulation. The velocity vector the Pressure contour. the change of residual along the iteration number. and the dynamic head are simulated by solving the Navier-Stokes equations for the comparison of four example cases.

• MALSORI
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• no.40
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• pp.51-63
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• 2000

There are sentences where sentence stress is imposed on a specific word. These sentences are called 'focused sentences'. The purpose of this paper is to investigate the variation of pitch, duration, amplitude in focused words. It is noted that pitch of a focused word is higher than that of unfocused words irrespective of the accentual pattern, and that contour tones such as HL or LH are realized longer when these tones appear in focused words. Not only the noun but also the following particle like '-boda' is higher when these words are in focus. Hence pitch is proved to be the most salient prosodic feature of the focused sentence.

• Magazine of the Korean Society of Agricultural Engineers
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• v.30 no.4
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• pp.134-153
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• 1988

This paper was carried out to investigate the existence of a unique stress- strain behavior by obtaining some factors influencing the time dependent stress- strain behavior of clay. The results obtained from this study were summarized as follows ; 1. The relationship between stress ratro and strain in normally consolidated clay was in- dependent on pre-shear consolidation pressure. Therefore, shear strain could be expressed as a function with stress ratio. 2. The constitutive equation of shear strain on Modified Carn Clay Model coincided better with the observed value than Cam Clay Model. 3. The relationships between deviator stress and shear strain, between pore water pressure and shear strain were unified by the mean equivalent pressure. 4. The shear strain contour in norrnally consolidated clay was increased linearly through origin, but that in overconsolidated clay was not in accordance with the result of the former. 5. Because the effective stress path of normally consolidated clay was unified by the mean equivalent pressure, state boundary surface in (e,p,q) space was transformed into two dimensional surface. But it was considered to be suitable that the unified stress- strain in overconsolidated clay be expressed by a function with overconsolidation ratio. 6. The deviator for constant strain was increased linearly with increment of strain rate ($\varepsilon$) on semi-log scale, but pore water pressure was decreased. 7. The behavior of stress relaxation was transformed from linear to curvilinear with inc - rement of strain rate before stress relaxation test, and pore water pressure was increased in total range. 8. The strain of creep was increased linearly with increment of time on semi-log scale. The greater the strain rate before creep test became, the greater the increment of strain of creep became. And the pore water pressure during creep test was increased generally with increment of time on semi-log scale.

• Wind and Structures
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• v.27 no.5
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• pp.347-356
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• 2018

In this paper, stress distribution for a structurally stable greenhouse is considered in the present paper with subsequent investigation into the detailed stress distribution contour with the variation of self-weight and wind pressure level designation method under wind velocity of less than 30 m/sec. For reliable analysis, wind pressure coefficients of a single greenhouse unit were modeled and compared with experiment with correlation coefficient greater than 0.99. Wind load level was designated twofold: direct mapping of fluid dynamic analysis and conversion of modeled results into wind pressure coefficients ($C_P$). Finally, design criteria of EN1991-1-4 and NEN3859 were applied in terms of their wind pressure coefficients for comparison. $C_P$ of CFD result was low in the most of the modeled area but was high only in the first roof wind facing and the last lee facing areas. Besides, structural analysis results were similar in terms of stress distribution as per EN and direct mapping while NEN revealed higher level of stress for the last roof area. The maximum stress levels are arranged in decreasing order of mapping, EN, and NEN, generating 8% error observed between the EN and mapping results under 30 m/sec of wind velocity. On the other hand, effect of dead weight on the stress distribution was investigated via variation of high stress position with wind velocity, confirming shift of such position from the center to the forward head wind direction. The sensitivity of stress for wind velocity was less than 0.8% and negligible at wind velocity greater than 20 m/sec, thus eliminating self-weight effect.

• Speech Sciences
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• v.5 no.2
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• pp.57-75
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• 1999

The purpose of this paper is to develop an English prosody training system using PC for Korean learners of English. The program is called Intonation Training Tool (ITT). It operates on DOS 5.0. The hardware for this program requires over IBM PC 386 with 4 MBytes main memory, SVGA (1 MByte or more) for graphic, soundblaster 16 and over 14 inch monitor size. The ITT program operates this way: the learners can listen as well as see the English teacher's stress and intonation patterns on the monitor. The learner practices the same patterns with a microphone. This program facilitates the learner's stress and intonation patterns to overlap the teacher's patterns. The learner can find his/her stress and intonation errors and correct these independently. This program is expected to be a highly efficient learning tool for Korean learners of English in their English prosody training in the English class without the aid of a native English speaker in the classroom.

• Journal of the Korean Geotechnical Society
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• v.15 no.1
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• pp.151-160
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• 1999

A series of laboratory tests for the marine clay sampled under the sea of Kwangyang bay have been conducted. The main types of tests are the general index property tests, the oedometer tests and the triaxial compression tests in both undrained(CIU) and drained(CID) conditions. The clayey samples, classified as CL, CH with natural water content of 38.3~84.6% and liquidity index of 0.71~0.98, are in the normally consolidated state with O.C.R. of 1.0l~l.60. The undrained stress path from CIU tests can be normalized with isotropic consolidation pressure$(p_0)$ and equal shear strain contour is linear passing through the origin in the (q, p) plot. The undrained shear strain is found to be the only function of the stress ratio($\eta$) and linear with intercept in the ($\varepsilon/\eta,\eta$) plot. The built-up pore pressure normalized with pc is also linear with respect to $\eta$. and its slope is defined by ´C´ as a pore pressure parameter. Equations to predict the undrained stress path and the shear strain are proposed. It is proved that the proposed equations give better agreements to the measured values than the Cam-clay theories. The failure points of the stress path are located on the same C.S.L. in (q, p) plot during both CIU and CID tests, which justifies the concept of critical state theory.

• Transactions of the Korean Society of Mechanical Engineers
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• v.1 no.2
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• pp.73-81
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• 1977

It is well known fact that there is a theoretical analogous relation ship in terms of differential equation between the stress distribution of a bar under pure torsional moment and the deflection of a membrane subjected to a uniform pressure. This relationship has been applied to the experimental determination of torsional stresses with troublesome and elaborative measuring procedure since Griffith's invention of the soap-film apparatus. In this paper, the soap-film was replaced by a highly polished steel plate and whole visualable deflectional contour-line-map was able to obtain by using Michelson Interferometer with Ne-He Gas Laser lignt source enabling to determine the stress distribution in the vicnity of the symmetrical inner-boundary in a section. Experimental results were satisfactory and the margin of error in the measurement was lower than 1%.

• Proceedings of the Korea Concrete Institute Conference
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• 2004.05a
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• pp.510-513
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• 2004

The objectives of this research are to evaluate the effect of the compressive strength of concrete, reinforcing bar size, spacing of column transverse bars related to the concrete confinement effects on anchorage bond strength and bond behavior of beam-column joints subjected to cyclic loading and to predict the bond behavior of beam-column joints according to the variables by Finite Element Analysis appling the interface element between concrete and reinforced bar surface in a three-dimensional configuration. This paper shows that to verify the results by three-dimensional nonlinear finite element analysis appling a interface element, the test results that were already conducted are compared with analytic results. The behavior of bond and anchorage of beam bar is expressed by a local bond stress-slip relationship and the failure mode of bond is predicted by principal stress contour.

• Journal of Navigation and Port Research
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• v.29 no.6 s.102
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• pp.523-528
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• 2005

The flow analysis is made to simulate the turbulent flow in the pipe with an obstacle. The models used are k-$\epsilon$, k-$\omega$, Spalart-Allmaras and Reynolds. The structured grid is used for the simulation The velocity vector, the pressure contour, the change of residual along the iteration number and the dynamic head are simulated for the comparison of four example cases. For the analysis, the commercial code is used.

• Structural Engineering and Mechanics
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• v.53 no.1
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• pp.147-158
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• 2015

Elements used in steel structures may be considered as an assembly of number of thin flat walls. Local buckling of these members can limit the buckling capacity of axial load resistance or flexural strength. We can avoid a premature failure, caused by effects of local buckling, by limiting the value of the wall slenderness which depend on its critical buckling stress. According to Eurocode 3, the buckling stress is calculated for an internal wall assuming that the latter is a simply supported plate on its contour. This assumption considers, without further requirement, that the two orthogonal walls to this wall are sufficiently rigid to constitute fixed supports to it. In this paper, we focus on webs of steel profiles that are internal walls delimited by flanges profiles. The objective is to determine, for a given web, flanges dimensions from which the latter can be considered as simple support for this web.