• International Journal of Ocean System Engineering
• /
• v.3 no.4
• /
• pp.218-224
• /
• 2013

This paper describes the design and control of a hovering AUV test-bed and analyzes the dynamic performance of the vehicle using simulation programs. The main purpose of this vehicle is to carry out fundamental tests of its station keeping, attitude control, and desired position tracking. Its configuration is similar to the general appearance of an ROV for underwater operations, and its dimensions are $0.75m{\times}0.5m{\times}0.5m$. It has four 450-W thrusters for longitudinal/lateral/vertical propulsion and is equipped with a pressure sensor for measuring the water depth and a magnetic compass for measuring its heading angle. The navigation of the vehicle is controlled by an onboard Pentium III-class computer, which runs with the help of the Windows XP operating system. This provides an appropriate environment for developing the various algorithms needed for developing and advancing a hovering AUV.

• Proceedings of the KIEE Conference
• /
• 2001.07c
• /
• pp.1712-1714
• /
• 2001

This paper deals with the development and application of an inner corrosion detector for the ACSR(Aluminum Conductor Steel Reinforced) power lines. The detector runs on an ACSR power line and inspects the inner corrosion of the conductor using the technology of the nondestructive eddy current test. It is consists of an ECT sensor, signal processing units, a RF transmitter/receiver, and etc.. The experimental result through field tests shows the detector can efficiently find both the zinc and aluminum loss of ACSR power lines.

• Proceedings of the KSR Conference
• /
• 2007.05a
• /
• pp.686-691
• /
• 2007

The ride comfort is more important according to train speedup. Generally it is defined as the vehicle vibration. There are many studies on evaluation method of ride comfort for railway. In the case of Korean high speed train(HSR 350x), the ride comfort has been assessed by statistical method according to UIC 513R. To verify the design requirements for the performance of HSR 350x, the qualification tests had been conducted from August 19, 2002 to December 2004 and the stabilization and reliability tests are carried out nowadays. Up to December 2006, total test runs and the accumulated milage of the train were 357 times and 164,000km, respectively. A total of 352 ride indices had been acquired through the on-line test from Aug. 2002 to Dec. 2006. In this paper, we have reviewed the characteristics of ride comfort for HSR 350x according to the operational conditions, such as load and track conditions, season and used time, by using the tests data.

• Journal of Biosystems Engineering
• /
• v.23 no.6
• /
• pp.549-560
• /
• 1998

The dynamic model of a tractor-trailer system developed in the first part of this paper was verified in this article by comparing the simulated acceleration responses of the system with actually measured ones. A commercially available tractor and a trailer were used for the verification test. Values of the model parameters were measured or theoretically derived if the measurement was practically impossible. The tractor-trailer system was operated with different forward speeds over three equally spaced half-sine bumps on the flat concrete surface. Results of the verification tests showed that autospectra of the measured and simulated accelerations of the tractor-trailer system agreed well up to the frequencies slightly feater than the fundamental frequencies of the ground excitations and at the frequencies of engine excitations. The mean of normalized errors of the simulated responses to the measured ones was estimated to be less than 10% for all the test runs. The peak responses in the autospectra also coincided well both in the frequency and magnitude.

• Journal of the Korean Society for Precision Engineering
• /
• v.16 no.4 s.97
• /
• pp.19-25
• /
• 1999

This paper addresses a development work of a SLA apparatus on laboratory basis. The SLA test machine is composed of optical, movement, curing and control subsystems. Optical part is performed by a He-Cd laser with mirror combination and mechanical movement is achieved by X-Y table. The developed system is evaluated by several test runs, and shows a good precision capability in forming a basic part. The technique used in this work can be extended to replace the high technology transfer cost of commercial RP machine.

• Proceedings of the KSR Conference
• /
• 2009.05a
• /
• pp.1218-1223
• /
• 2009

LIM(Linear induction motor)s are the main type of motors used for urban Maglev vehicles because they are less expensive to operate at a lower speed than linear synchronous motors. An LIM generates an attraction force while running, which perturbs the air gap of the electromagnet. This undesirable air gap variation could result in the mechanical contact of an electromagnet with the reaction plate. For this reason, the magnitude of the air gap variation must be limited within a certain range. The air gap changes when running the 1/2 vehicle under development for testing are analyzed through a test on the test track at KIMM. The results from this study could be used to minimize the air gap variations due to attraction force from LIM.

• Proceedings of the KIEE Conference
• /
• 2000.07c
• /
• pp.1963-1965
• /
• 2000

This paper deals with a problem of detecting the inner corrosion of the ACSR(Aluminum Conductor Steel Reinforced) power lines using a detector which consists of an ECT(Eddy Current Test) sensor, a constant current service, a signal processing unit, and a RF transmitter/receiver unit. The detector runs on the ACSR transmission line and inspects the corrosion of the conductor using the technic of the nondestructive eddy current test. The experimental result shows this detector can efficiently find the zinc loss in ACSR power lines.

• The Transactions of The Korean Institute of Electrical Engineers
• /
• v.56 no.8
• /
• pp.1466-1470
• /
• 2007

MEMS design flow based on DFM concept is presented and applied to gyroscope design as a test case. It is purposed to contribute to the yield improvement by considering the process-related parameters from the design phase. After defining the performance requirements, the sensitivity analysis should be done on the draft design(s) to find out the key parameters related with the device performance. By doing so, TEG can be designed for the selected process and/or material parameters. Through a set of test runs, the process capability is characterized and the material properties are extracted using the TEG. Then we can estimate the virtual yield of the current process for the designed device by running Monte Carlo analysis where the process and/or material property variations are considered. The estimated yield will make us redesign the device to be more robust or improve the current process to have the smaller variations.

• Proceedings of the Korean Society of Propulsion Engineers Conference
• /
• 2008.03a
• /
• pp.855-861
• /
• 2008

Micro wave rotor is expected to improve the performance of micro gas turbines drastically. In the present study, a micro wave rotor test rig was designed and built for micro gas turbines of 1-10 kW output range, and its test runs were carried out with cold air flow. In the previous experiments, the leakage loss had large influence on its operating condition. Therefore, abradable coating was applied on the end walls to achieve the operation with zero clearance for leakage reduction and its improvement on the operating condition is discussed in this study.

• Proceedings of the KSR Conference
• /
• 2008.11b
• /
• pp.864-869
• /
• 2008

Magnetic Levitated(Maglev) Vehicle, which utilizes electromagnetic forces between dual-pole electromagnets and a steel rail, generally runs on guideway structures. A prototype of an Urban Maglev Vehicle has been developed and tested in Korea, This study was conducted as a cooperation research subject of the 3-1 subject, performance improvement of maglev track structures, of the Center for Urban Maglev Program, statred in 2006. As the Maglev load is distributed rather than concentrated, a field test was conducted on Simple Span PSC-BOX Girder Bridge(L=25.0m) of the Expo-Maglev test track in Daejeon to examine the dynamic effect of the Maglev load on the bridge. Numerical analyses were also performed up to the maximum passing speed of 110 km/h by 10 km/h increments of Maglev Vehicle using Finite Element model of bridge, and girder deflections, accelerations and Dynamic Amplification Factor (DAF) are analysed.