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Oh, Dong-Joon;Howard, I.C.;Yates, J.R.
- Journal of Mechanical Science and Technology
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- v.14 no.9
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- pp.978-984
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- 2000
The aim of this study is to investigate the ductile fracture behaviour under Mode I loading using SA533B pressure vessel steel. Experiments consist of the Round Notch Bar Test (RNB), Single Edge Crack Bending Test (SECB), and V-Notch Bar Test (VNB). Results from the RNB test were used to tune the damage modelling constant. The other tests were performed to acquire the J-resistance curves and to confirm the damage constants. Microstructural observation includes the measurement of crack profile to obtain the roughness parameter. Finally, simulation using Rousellier Ductile Damage Theory (RDDT) was carried out with 4-node quadrilateral element ($L_c=0.25\;mm$). For the crack advance, the failed element removal technique was adopted with a ${\beta}$ criterion. In conclusion, the predicted simulation using RDDT showed a good agreement with the experimental results. A trial using a roughness parameter was made for a new evaluation of J-resistance curve, which is more conservative than the conventional one.
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Kim, C.K.;Cheon, J.M.;Lee, J.M.;Kweon, S.M.
- Proceedings of the KIEE Conference
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- 2004.07d
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- pp.2374-2376
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- 2004
In this paper, we describe a DSP-based test apparatus for Control Element Drive Mechanism (CEDM). Using this apparatus, we can catch the mechanical and electrical characteristics of CEDM and obtain the information about the improvement of CEDM and the design of CEDM power controller. The test apparatus for CEDM introduced in this paper can input firing angles directly into gate drive circuits of thyristors so that this method can be used to derive the maximum and minimum values of firing angles within available limits for a 3-phase half-wave rectifier. Angle inputs help us understand each coil's response characteristics. Since this apparatus generates a serial sequence for CEDM insertion and withdrawal operations, we may judge whether CEDM works correctly as expected or not in each phase of a step movement.
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Bykowski, B.B.;Bartley, G.J.J.;Webb, C.C.;Zhan, R.;Burrahm, R.W.
- International Journal of Automotive Technology
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- v.7 no.3
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- pp.245-249
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- 2006
Accelerated aging of engine exhaust system components such as catalytic converters are traditionally performed using an engine/dynamometer test stand. $SwRI^{(R)}'s\;FOCAS^{(R)}$ system reduces or eliminates many of the engine based aging limitations. This paper will describe several studies. These include: 1) replication of engine based catalyst aging cycles with added precision and dependability; 2) catalyst aging with and without lubricating oil effects; 3) effects of lubricant phosphorus on catalyst performance; and 4) the potential to thermally age components beyond the capabilities of engine based systems. The first study includes the development of the SwRI FOCAS system to run programmed aging conditions with or without lubricating oil. A description of the subsystems is given. The second two studies used the SwRI FOCAS system to age catalysts. One study compared thermal-only aging using of the SwRI FOCAS system with equivalent aging on a traditional engine/dynamometer test stand. The other study examined the effect on catalyst performance of two lubricating oils containing different levels of phosphorus, and compared the results to field data generated using the same oils in a fleet of vehicles.
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Hwang, G.H.;Jang, J.W.;Han, H.L.;Son, J.H.
- Proceedings of the IEEK Conference
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- 2008.06a
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- pp.1131-1132
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- 2008
In this paper, we developed UHF RFID R/W system using AT91SAM7S256(ARM chip), UHF RFID R/W module (WJ7090) and wireless LAN(IEEE 802.11.a/b). And we developed a transmission/receiving packet which is send to UHF R/W module in AT91SAM7S256. In order to show the usefulness of UHF RFID R/W system, we executed a performance test. The developed UHF RFID R/W system shows better performance for reading of RFID tag and data transmission through wireless LAN.
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Kim, K.H.;Sun, J.H.;Kim, Y.B.;Cho, Y.O.
- Proceedings of the KIEE Conference
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- 1993.07b
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- pp.636-639
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- 1993
This paper is discribed the results of insulation characteristic tests that are DC leakage current, test, tan${\delta}$ test, AC breakdown test and observation of tree in the used 6.6kV CV cables. In the correlation of these tests, the tan${\delta}$ test stands for the main deterioration factor of cable insulation.
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Min, B.G.;Ryu, S.P.;Baek, B.S.;Kim, Y.P.;Shin, H.J.;Kim, D.U.;Yoo, D.W.;Baek, J.W.
- Proceedings of the KIEE Conference
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- 1996.07a
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- pp.550-552
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- 1996
In order to develop a noble Uninterruptible Power Supply(UPS), we designed and manufactured the UPS using the PWM converter and the Resonant DC Link Inverter. This paper describes the power circuits, the key techniques, the control and monitoring unit of the developed UPS. Finally, using the UPS we verified the superiority through the type test.
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