• Proceedings of the KSRS Conference
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• 2002.10a
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• pp.610-614
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• 2002

Time-mean and absolute geostrophic velocities of the Kuroshio current south of Japan are derived from TOPEX/Poseidon altimeter data using a Gaussian jet model. When compared with simultaneous measurements from a shipboard acoustic Doppler current profiler (ADCP) at two intersection points, the altimetric and ADCP absolute velocities correlate well with the correlation of 0.55 to 0.74. The time-mean velocity is accurate to 1 cm s$^{-1}$ to 5 cm s$^{-1}$. The errors in the absolute and the mean velocities are similar to those reported previously far other currents. The comparable performance suggests the Gaussian jet model is a promising methodology for determining absolute geostrophic velocities, noting that in this region the Kuroshio does not meander sufficiently, which provides unfavorable environment for the performance of the Gaussian jet model.

• Bulletin of the Korean Mathematical Society
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• v.52 no.3
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• pp.925-933
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• 2015

It is well-known that the area of parabolic region between a parabola and any chord $P_1P_2$ on the parabola is four thirds of the area of triangle ${\Delta}P_1P_2P$. Here we denote by P the point on the parabola where the tangent is parallel to the chord $P_1P_2$. In the previous works, the first and third authors of the present paper proved that this property is a characteristic one of parabolas. In this paper, with respect to triangles ${\Delta}P_1P_2PQ$ where Q is the intersection point of two tangents to X at $P_1$ and $P_2$ we establish some characterization theorems for parabolas.

• Journal of Information Technology Applications and Management
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• v.23 no.3
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• pp.87-97
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• 2016

This paper proposes a fast sound source localization method using a TDOA sign-based algorithm. We present an L-shaped microphone set-up which creates four major regions in the range of $0^{\circ}{\sim}360^{\circ}$ by the intersection of the positive and negative regions of the individual microphone pairs. Then, we make an initial source region prediction based on the signs of two TDOA estimates before computing the azimuth value. Also, we apply a threshold and angle comparison to tackle the existing front-back confusion problem. Our experimental results show that the proposed method is comparable in accuracy to previous three microphone array methods; however, it takes a shorter computation time because we compute only two TDOA values.

• Journal of the Korean Institute of Telematics and Electronics
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• v.14 no.5
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• pp.1-6
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• 1977

When the input of synchronizer which is used for the purpose of synchronizing the master clock of computer with the interrupt system, a sort of random variable device, is gated with asynchronous intersection of the fall time of the master clock and the risetime oi the interrupt request, synchronizer is drived in Metastable region. This paper is presented circuit analysis of Metastable phenomena and analysis for transient process from metastable point to stable state, and also realities the collect logic with Inverter and open collector methods with a view to improving logic failure caused by the mishappen phenomena.

• Journal of the Korean Society for Precision Engineering
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• v.8 no.4
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• pp.137-145
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• 1991

A universal joint is a connecting device of two hinges which can transmit torque from one shaft to another at fixed or at varying angles of intersection. It has been used properly not only as rotational but also as intermittent motion. For the particular kinematics condition of a universal joint, torsional and bending vibrations are produced excessively in an elastic driveline. In this paper only the torsional vibration behavior of a driveline with universal joints is analyzed numerically with the discrete model and a design method of the dynamic vibration damper is proposed, in order to reduce torsional vibrations especially in resonance region as a result of parametric variation.

• JSTS:Journal of Semiconductor Technology and Science
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• v.15 no.6
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• pp.653-657
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• 2015

A new paired gate-source voltage RF capacitance-voltage (C-V) method of extracting the effective channel length and parasitic capacitance using the intersection between two closely spaced linear regression lines of the gate capacitance versus gate length measured from S-parameters is proposed to remove errors from conventional C-V methods. Physically verified results are obtained at the gate-source voltage range where the slope of the gate capacitance versus gate-source voltage is maximized in the inversion region. The accuracy of this method is demonstrated by finding extracted value corresponding to the metallurgical channel length.

• Journal of information and communication convergence engineering
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• v.14 no.4
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• pp.215-221
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• 2016

We consider a design of a combined quantizer and estimator for distributed systems wherein each node quantizes its measurement without any communication among the nodes and transmits it to a fusion node for estimation. Noting that the quantization partitions minimizing the estimation error are not independently encoded at nodes, we focus on the parameter regions created by the partitions and propose a cluster-based quantization algorithm that iteratively finds a given number of clusters of parameter regions with each region being closer to the corresponding codeword than to the other codewords. We introduce a new metric to determine the distance between codewords and parameter regions. We also discuss that the fusion node can perform an efficient estimation by finding the intersection of the clusters sent from the nodes. We demonstrate through experiments that the proposed design achieves a significant performance gain with a low complexity as compared to the previous designs.

• Journal of Institute of Control, Robotics and Systems
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• v.12 no.10
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• pp.962-967
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• 2006

Indoor positioning is highlighted recently, and various kinds of indoor positioning systems are under developments. Since positioning systems have their own characteristics, proper positioning scheme should be chosen according to the required specifications. Positioning methods are classified into time-based and angle-based one. This paper presents the error analysis of time-based and angle-based location methods. Because measurements of these methods are nonlinear, linearizations are needed in both cases to estimate the user position. In the linearization, Gauss-Newton method is used in both cases. To analyze the position error, we investigate the error ellipse parameters that include eccentricity, rotation angle, and the size of ellipse. Simulation results show that the major axes of TOA and AOA method lie in different quadrants at most region of workspace, especially where the geometry is poor. When the TOA/AOA hybrid is employed, it is found that the error ellipse is reduced to the intersection of ellipses of TOA and AOA.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 1997.04a
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• pp.594-601
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• 1997

Propeller fans are commonly equipped in outdoor units of air-conditioners to provide effective cooling in a dried heat exchanger. A new design technique was developed to satisfy requirements of aerodynamic and aeroacoustic performance, which employs the intersection method of two cylinders for mean camber line. Three proto-types of propeller fan including Palm-Shaped, Highly-Swept(PSHS) fan (proto 3)were not only to provide low lift forces for dipole sound, but also to reduce the organized tip vortices interacting with the fan guide causing narrow-banded rotating instabilities. Cross-correlation technique was applied to study flow noise source characteristics for three proto-type fans designed. The cross-correlations between a microphone at far field and a hot-wire sensor at near field show that flows near hub region of proto 3 fan are less organized and the flow structures especially at high flow rate coefficients for proto 3 fan are less correlated with noise generated than other proto-types fans.

• Molecules and Cells
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• v.20 no.2
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• pp.167-172
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• 2005

Ceruloplasmin (Cp) is a copper protein with important functions in iron homeostasis and in inflammation. Cp mRNA expression is induced by interferon (IFN)-${\gamma}$ in U937 monocytic cells, but synthesis of Cp protein is halted after about 12 h by transcript-specific translational silencing. The silencing mechanism requires binding of a 4-component cytosolic inhibitor complex, IFN-gamma-activated inhibitor of translation (GAIT), to a defined structural element (GAIT element) in the Cp 3'-UTR. Translational silencing of Cp mRNA requires the essential proteins of mRNA circularization, suggesting that the translational inhibition requires end-to-end mRNA closure. These studies describe a new mechanism of translational control, and may shed light on the role that macrophage-derived Cp plays at the intersection of iron homeostasis and inflammation.