• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.5 no.1
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• pp.17-26
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• 1996

In this paper, we have studied about the relationships between a core gap and a feeding velocity, an amplitude and the core gap by the exciting force, the parts movement and a bowl materials, and the feeding velocity and the weight of the parts in the parts feeder. The obtained are as follow : 1) Optimal condition of mean feeding velocity is speeded up largely when the core gap is in 0.6mm. 2) It can be safe to say that the relation between the feeding velocity and the exciting voltage relay on the core gap. 3) An exciting voltage is rised by an increase of the weight, but an amplitude has been in the range between 23$mu extrm{m}$ through 40${\mu}{\textrm}{m}$.

• Proceedings of the KSRS Conference
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• 2008.10a
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• pp.240-242
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• 2008

In the present article, we analyze airborne Pi-SAR (Polarimetric-Interferometric SAR) X-band images of ocean waves around the Miyake Island at approximately 180 km south from Tokyo, Japan. Two images of a same scene were produced at approximately 40 min. interval from two directions at right angles. One image shows dominant range travelling waves, but the other image shows a different wave pattern. This difference can be caused by the different image modulations of RCS and velocity bunching. We have estimated the dominant wavelength from the image of range waves, and from the wave phase velocity computed from the dispersion relation (though no wave height data were available), the image intensity is computed by using the velocity bunching model. The comparison of the result with the second image at right angle strongly suggests the evidence of velocity bunching.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.29 no.10 s.241
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• pp.1307-1314
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• 2005

The most important factor of the traffic accident on the wet road is a tire slip caused by hydroplaning. Meanwhile, hydroplaning characteristics are influenced very greatly by the vehicle velocity, so it is very important to reveal the relation between hydroplaning and the vehicle velocity. Since the experiment study is considerably limited, recently the numerical simulation using finite element method(FEM) and finite volume method(FVM) is widely adopted. In this paper, the effect of the vehicle velocity on the hydroplaning characteristics is investigated through the hydroplaning analysis using MSC/Dytran.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.5 no.2
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• pp.51-57
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• 1993

It is often assumed that the wave velocity at the bottom given by potential wave theory il the same as the wave velocity at the top of the turbulent boundary layer. This assumption is found to be the major cause of the error detected by recent elaborate theories and numerical models for the description of velocity profile near the sea bottom. A relationship is suggested between the potential velocity and the real boundary velocity. Based on this relation, the existing theories of Jonsson (1967) and Fredsoe (1984) are refined for the estimation of wave friction factor, and the computation results of the modified theories are favourably compared with the published laboratory results.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.20 no.6
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• pp.2036-2045
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• 1996

An experimental study has been performed to obtain the effect of relative velocity between droplet and environmental gas on the evaporation of a n-heptane free droplet of 180 $\mu$m in diameter flying in a hot and normal pressure air flow. Measurement of droplet diameter and velocity was conducted in a series of time by an electrically controlled optical system. From the experimental results, an empirical equation associated with the relation between evaporation rate constant and relative velocity was obtained.

• The Bulletin of The Korean Astronomical Society
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• v.41 no.2
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• pp.32.1-32.1
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• 2016

Early-type galaxies (ETGs) are supposed to follow the virial relation M ~ sigma^2 * R_e, with M being the galaxy mass, sigma being the stellar velocity dispersion, and R_e being the (2D) effective radius. I apply this relation to (a) the ATLAS3D sample and (b) the sample of Saglia et al. (2016). The two datasets reveal a statistically significant tilt of the empirical relation relative to the theoretical virial relation such that M ~ (sigma^2 * R_e)^0.92 with zero intrinsic scatter. This tilt disappears when replacing R_e with the semi-major axis of the projected half-light ellipse, a. Accordingly, a, not R_e, is the correct proxy for the scale radius of ETGs. By geometry, this implies that early-type galaxies are axisymmetric and oblate in general, in agreement with recent results from modeling based on kinematics and light distributions.

• Journal of Applied Reliability
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• v.18 no.3
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• pp.208-212
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• 2018

Purpose: The three Vs of volume, velocity and variety are commonly used to characterize different aspects of Big Data. Volume refers to the amount of data, variety refers to the number of types of data and velocity refers to the speed of data processing. According to these characteristics, the size of Big Data varies rapidly, some data buckets will contain outliers, and buckets might have different sizes. Correlation plays a big role in Big Data. We need something better than usual correlation measures. Methods: The correlation measures offered by traditional statistics are compared. And conditions to meet the characteristics of Big Data are suggested. Finally the correlation measure that satisfies the suggested conditions is recommended. Results: Mutual Information satisfies the suggested conditions. Conclusion: This article builds on traditional correlation measures to analyze the co-relation between two variables. The conditions for correlation measures to meet the characteristics of Big Data are suggested. The correlation measure that satisfies these conditions is recommended. It is Mutual Information.

• Wind and Structures
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• v.11 no.4
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• pp.291-302
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• 2008

Three-dimensional engineering simulations of momentum-driven tornado-like vortices are conducted to investigate the flow dynamics dependency on swirl ratio and the possible relation with real tornado Fujita scales. Numerical results are benchmarked against the laboratory experimental results of Baker (1981) for a fixed swirl ratio: S = 0.28. The simulations are then extended for higher swirl ratios up to S = 2 and the variation of the velocity and pressure flow fields are observed. The flow evolves from the formation of a laminar vortex at low swirl ratio to turbulent vortex breakdown, followed by the vortex touch down at higher swirls. The high swirl ratios results are further matched with full scale data from the Spencer, South Dakota F4 tornado of May 30, 1998 (Sarkar, et al. 2005) and approximate velocity and length scales are determined.

• Proceedings of the KIEE Conference
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• 1998.07g
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• pp.2461-2463
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• 1998

The container crane is more expensive than other cranes, and is designed for efficient use. Since there are more control variables than other crane has more fault factors. Therefore it is important to reduce these factors efficiently and also to increase the capacity to move more freight in due time. To solve the above problems the velocity relation of the motor will be examined. In this paper the velocity relation of the motor will be expressed in a mathematical equations for efficient control.

• Proceedings of the KIEE Conference
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• 2000.07d
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• pp.2567-2568
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• 2000

The container crane is more expensive than other cranes, and is designed for efficient use. Since there are more control variables than other crane has more fault factors, Therefore it is important to reduce these factors efficiently and also to increase the capacity to move more freight in due time. To solve the above problems the velocity relation of the motor will be examined. In this paper, the velocity relation of the motor will be expressed in a mathematical equations for efficient control.