• Journal of Applied Reliability
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• v.9 no.1
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• pp.47-58
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• 2009

In this paper, an accelerated life test procedure for a vacuum cleaner motor is proposed. We investigate the failure mechanism of the motor and select some accelerating factors and determine the orifice size as a key accelerating factor. Three stress levels of orifice size are tested and the failure data with censored data are analyzed. The modified accelerating test will reduce the test time in design phase by using the accelerating factor.

• Journal of the Korean Society for Precision Engineering
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• v.6 no.3
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• pp.46-59
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• 1989

The purpose of test fixture is to mechanically couple energy from a shaker into a test specimen. And then it is necessary to design a fixture of shich the fundamental natural frequency is over than one half times as high as the highest frequency of interest. But the dynamic behavior of vibration test fixture is usually different from, often far different from, what has been calculated. In this paper, the optimal dimensionless frequency parameter, ${lambda}$'s, are calculated from the test results of a various and complex shaped fixtures.

• Journal of the military operations research society of Korea
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• v.27 no.2
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• pp.124-133
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• 2001

The purpose of this study is investigate the differences among parametric and nonparametric test statistics for the tree alternative hypothesis in the randomized block design. As the results, it was found that there was no large differences among parametric and nonparametric test statistics in power when the block sizes were larger, and Hollander's statistic had better power than other nonparametric test statistics. It is recommended that Hollander's test statistic is more useful method when we have no information about the distribution of population.

• International Journal of Aerospace System Engineering
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• v.4 no.2
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• pp.1-4
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• 2017

This work dealt with design and manufacturing of WIG vehicle wing using carbon/epoxy composite materials. In this study, structural design and analysis of carbon composite structure for WIG craft were performed. Firstly, structural design requirement of wing for WIG vehicle was investigated. After structural design, the structural analysis of the wing was performed by the finite element analysis method. It was performed that the stress, displacement and buckling analysis at the applied load condition. And also, manufacturing of subscale wing using carbon/epoxy composite materials was carried out. After structural test of target structure, structural test results were compared with analysis results. Through the structural analysis and test, it was confirmed that the designed wing structure is safety.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.22 no.3_1spc
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• pp.593-599
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• 2013

In this study, a test-bench for developing and verifying a 1- or 2-axis nanopositioner was manufactured. Using this test-bench, adesigned and manufactured flexure stage based on an analysis can configure nanopositioning systems. A breadboard and fixture were fabricated to be equipped with various types of mechanisms and sizes of stages. The test-bench has linear encoders for calibrating sensors and verifying the orthogonality and parasitic motion of 2-axis nested-type nanopositioners. The controller was developed using LabVIEW and a TI microcontroller. A case study that exemplified the test bench for developing a nanopositioner by senior undergraduate students is shown.

• Journal of KIISE:Software and Applications
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• v.32 no.7
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• pp.592-600
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• 2005

Systematically extracting the test patterns of hot spots in an object-oriented software framework is a prerequisite for thoroughly testing the framework's functionality in a variety of contexts in which the framework is extended for reuse. This paper proposes a method for analyzing the design patterns and extracting the test patterns from the interaction test patterns of hot spots in an object-oriented framework. Based on the design pattern of the framework's hot spot, our method captures the object behavior allowed in that hot spot by means of statecharts, which are then used to generate the interaction test patterns and test cases. The generated test patterns and test cases can be applied repeatedly to applications which are built from extending the framework.

• Journal of Institute of Control, Robotics and Systems
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• v.14 no.8
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• pp.824-836
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• 2008

Relaxed static stability(RSS) concept has been applied to improve aerodynamic performance of modern version supersonic jet fighter aircraft. Therefore, flight control systems are necessary to stabilize an unstable aircraft, and provides adequate handling qualities and achieve performance enhancements. Standard FCSDVP (Flight Control System Design and Verification Process) is provided to reduce development period of the flight control system. In addition, if this process is employed in developing flight control system, it reduces the trial and error for development and verification of flight control system. This paper addresses the flight control system design and verification process for the RSS aircraft utilizing design goal based on military specifications, linear and nonlinear system design and verification based on universal software, handling quality test based on HILS(Hardware In-the-Loop Simulator) environment, and ground and flight test results to verify aircraft dynamic flight responses.

• Journal of Institute of Control, Robotics and Systems
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• v.14 no.6
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• pp.523-529
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• 2008

In this paper, we proposed mobile LCD module test device on embedded based, when operating the existing LCD, divide flicker clearly in full frame, and configuration so as to support between other CPU interface, MDDI, SPI, 24Bit RGB interface, etc. that is based on a high-speed CPU. In addition, when demand to test about each pixel of LCD, it is possible to change IP design of H/W, FPGA, but proposed system is application possible without other design changing. Proposed system is made smaller and equipped with battery, so secure with mobility for effective test the LCD/OLED module and it is able to test the pattern by the client program, for example exiting picture, mpeg, simple pattern test and test per pixel, scale, rotation, Odd/Even pixel per video, etc. From now on, if integrating with independent test system and it is configured that is able to mutual communication and test, it is expected to reduce consumption of human resources and improve productivity for LCD module test.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2005.06a
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• pp.1416-1419
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• 2005

Design and manufacturing of plastic injection mold with cavity pressure/temperature sensors were performed in the present study for tensile test specimen. Standards of mold-base and tensile test specimen were used to design an injection molding system. Cavity pressure and temperature sensors were placed on the side of fixed platen of injection mold machine to prevent them from external impact damage. Injection molding experiments with variations of injection speed and melt temperature were performed and polycarbonate tensile specimens were prepared for the tensile test. It was shown that injection molding processing parameters can have effect on the mechanical properties of the plastic injection molded part.

• Journal of Aerospace System Engineering
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• v.14 no.6
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• pp.85-90
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• 2020

The infrared signature that is associated with an aircraft is mainly caused by heat released from the engine and the exhaust plume. In this study, a test-system was designed to observe the overall infrared signature characteristics of a turbofan engine during operation under ground running conditions and the infrared reduction features that result from different exhaust nozzle configurations. A test stand was designed for the 1400 lbf class turbofan engine that included a bell-mouth type intake, fuel supply system, a measurement system, and a data acquisition/control system. The design and verification of the test system were conducted so that the basic nozzle and various 2D nozzles could be applied to study the infrared signature produced by a turbofan engine exhaust.