• Journal of Ocean Engineering and Technology
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• v.34 no.1
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• pp.13-18
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• 2020

An azimuth propeller can generate thrust in all directions by rotating its housing with an electric motor. An azimuth propeller can be operated using several methods to stop a ship. This study aims to derive an efficient method to stop a ship safely using an azimuth propeller through full-scale maneuvering trials with the research vessel "NARA" of Pukyong National University in 4.63 m/s (9 kts). Five methods with different azimuth propeller operations were tested to stop the ship. The test results confirmed that the simultaneous use of the thrust and the hydrodynamic force acting on the strut is the most effective method to stop the ship.

• International Journal of Concrete Structures and Materials
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• v.9 no.3
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• pp.267-281
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• 2015

Six full-scale prestressed concrete (PC) I-beams with steel fibers were tested to failure in this work. Beams were cast without any traditional transverse steel reinforcement. The main objective of the study was to determine the effects of two variables-the shear-span-to-depth ratio and steel fiber dosage, on the web-shear and flexural-shear modes of beam failure. The beams were subjected to concentrated vertical loads up to their maximum shear or moment capacity using four hydraulic actuators in load and displacement control mode. During the load tests, vertical deflections and displacements at several critical points on the web in the end zone of the beams were measured. From the load tests, it was observed that the shear capacities of the beams increased significantly due to the addition of steel fibers in concrete. Complete replacement of traditional shear reinforcement with steel fibers also increased the ductility and energy dissipation capacity of the PC I-beams.

• Journal of the Korean Institute of Telematics and Electronics
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• v.8 no.1
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• pp.1-8
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• 1971

A survey meter which is used a G-M counter sensitive to beta and gamma radiation is studied. This device is completely transistorized, operated with battery, and can be read directly the 3 full-scale meter range: 2.5, 25 and 250 MR/HR respectively. The collector-coupled monostabel multivibrator consisting of a counting-rate meter circuit, and the astable blocking oscillator consisting of a dc-de converter for power supply are analyzed and derived the design dquations. To improve the resolving time of the G-M counter the device is designed to be triggered by low pulse in the order of 0.5v.

• Proceedings of the IEEK Conference
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• 2003.11a
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• pp.199-202
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• 2003

In this paper, we propose a new 3D coding method for heterogeneous systems over enhanced Access Grid (e-AG) with 3D display using spatio-temporal scalability. The proposed encoder produces four bit-streams: one base layer and enhancement layer l, 2 and 3. The base layer represents a video sequence for left eye with lower spatial resolution. An enhancement layer l provides additional bit-stream needed for reproduction of frames produced in base layer with full resolution. Similarly, the enhancement layer 2 represents a video sequence for right eye with lower spatial resolution and an enhancement layer 3 provides additional bit-stream needed for reproduction of its reference pictures with full resolution. In this system, temporal resolution reduction is obtained by dropping B-frames in the receiver according to network condition. The receiver system can select the spatial and temporal resolution of video sequence with its display condition by properly combining bit-streams.

• Journal of the Korean Institute of Telematics and Electronics C
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• v.35C no.12
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• pp.49-58
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• 1998

In this paper, we report new algorithms to select scan flip-flops for the no holding partial scan test method. The no holding partial scan test method is identical to the full scan test method except that some flip-flops are left unscanned. This test method does not hold scanned or unscanned flip-flops while shifting in test vectors, or applying them, or shifting out test results. The proposed algorithm allows a large number of flip-flops to be left unscanned while maintaining almost the complete full scan fault coverage.

• Journal of the Korean Institute of Telematics and Electronics A
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• v.33A no.5
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• pp.165-171
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• 1996

A noncoherent full-digital PN(pseudo noise) code acquisition/tracking loop has been presetned and implemented in FPGA for the CDMA band-limited direct-sequence spread-spectrum (DS-SS) signals. It employs a simple decimator to control of local PN code phase to lower the hardware cost, and a second order loop to enable the more accurate tracking. The proposed acquisition/tracking loop has been designed in RTL-level VHDL, synthesized into logic gates using the design analyzer of synopsys software, implemented in an ALTERA FPGA chip, and tested. The number of logic gates used in the implemented FPGA chip is around 7000. The functionality has been verified using a PC interface circuitry and a logic analyzer.

• Proceedings of the IEEK Conference
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• 1999.06a
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• pp.773-776
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• 1999

For providing good quality power steadily, it is required that operators manipulate the control system of power plant with the good knowledge of power plant system and the control strategies, and cope with accidents effectively. With those requirements, it is general to train operators in power plant control room using full-scope simulator. A full scope simulator adopts the I&C instruments in the main cotrol room, so has to include I/O interface system to interface the simulation computer with I&C instruments in main control room. In already developed simulators, most of I/O interface systems are closed. vendor-dependent. proprietary systems. so have the many disadvantages in terms of cost and maintenance. In this paper. we suggest the method to configure I/O interface system for Thermal Power Plant Simulator based on standard technology which gives the advantages of ease-of-use. cost effectiveness, and simplicity of maintenanceuse by using off-the-shelf products for system integration.

• Journal of the Korean Institute of Telematics and Electronics B
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• v.32B no.12
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• pp.1624-1634
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• 1995

Conventional full search block matching algorithm for motion estimation is computationally intensive and the resulting hardware cost is very high. In this paper, we present an efficient block matching algorithm using a 16:1 subsampling technique, and describe its hardware design. The algorithm reduces the number of pixels in calculating the mean absolute difference at each search location, instead of reducing the search locations.The algorithm is an extension of the block mating algorithm with 4:1 subsampling proposed by Liu and Zaccarin such that the amount of computation is reduced by a fact of 4(16 compared to the full search block matching algorithm) while producing similar performance.The algorithm can efficiently be designed into a hardware for real-time applications.

• Journal of international Conference on Electrical Machines and Systems
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• v.3 no.3
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• pp.252-255
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• 2014

In the case of long-stator linear drives, unlike rotative drives for which speed or position sensors are a single unit attached to the shaft, these sensors extend along the guideway. The position signal transmitted from maglev vehicle can't meet the need of the real-time propulsion control. In this paper the position estimator for propulsion inverter driving long stator linear synchronous motor (LSLSM) in high speed maglev train is proposed. In order to get the higher resolution of the position information transmitted from vehicle, Full order state observer is proposed for position estimator.

• Journal of the Korean Institute of Telematics and Electronics
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• v.9 no.3
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• pp.22-28
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• 1972

A new full-adder is proposed and it's operation-characteristic is described. The circuit proposed here was improved in operational stability and cicuit-configuration. The circuit is composed of a tunnel diode, Schottky-barrier diodes. The circuit design and it's opration is explained by considering the change of the load line when the input current is applied. The explanations are proved by experimental details.