The POWER4-based p690 systems offer the highest performance of the IBM eServer pSeries line of computers. Within the general-purpose UNIX server market, they also offer the highest levels of concurrent error detection, fault isolation, recovery, and availability. High availability is achieved by minimizing component failure rates through improvements in the base technology, and through design t...

In this work, spectral signal analyses are employed in fault detection and isolation scheme. The procedure was applied to detect the presence of fault in proces and suppose the processing in frequency domain of the data acquisition, which represent the known commands and the actual measure outcome. The approach has been applied to electrical motor and the results show that the fault detection s...

This paper presents a fault detection and isolation scheme for multirate systems with a fast input sampling rate and slower output sampling rates. We design a separate observer for each set of simultaneous measurements with the observer operating at their sampling rate. We use an unknown input observer design to allow state estimation in the presence of disturbances and modelling errors. The ob...

In this paper a generic method for fault detection and isolation (FDI) in manufacturing systems considered as discrete event systems (DES) is presented. The method uses an identified model of the closed loop of plant and controller built on the basis of observed fault free system behavior. An identification algorithm known from literature is used to determine the fault detection model in form o...

This paper tests some of the predictions of recent advances in trade theory that have focused on different trade patterns of firms within the same sector. Helpman, Melitz and Yeaple (2005) develop a model in which innate productivity differences between firms determine the degree of international engagement of firms: The least productive firms produce for the domestic market, better performers ...

Cause-e ect graphing is a well-known requirement based testing technique. However, since it was introduced by Myers in 1979, there seems not to have been any su ciently comprehensive studies to generate test cases from these graphs. This paper proposes to convert cause-e ect graphs into Boolean expressions and nd out the test cases using test input generation techniques for Boolean expressions,...

The development of on line model-based fault detection systems in machinery improves the operational reliability of industrial systems and reduces the operational and maintenance costs. In this direction, this paper presents the use of modelling information to determine changes in characteristics from measured data for the fault detection purpose of hydraulic driven machines as well as for the ...

In this paper we discuss the application of our recently developed nonlinear analytical redundancy (NLAR) fault detection technique to a two-degree of freedom robot manipulator. NLAR extends the traditional linear AR technique to derive the maximum possible number of fault detection tests into the continuous nonlinear domain. The ability to handle nonlinear systems vastly expands the accuracy a...

In this paper, we present an unified approach for fault detection and isolation in discrete-time systems affected by noises and faults on measurement and state equations. The proposed robust fault detection filter will be designed under less restrictive conditions compared with classical fault detection filter. After having parameterized the minimum-time left inverse of the system, the degrees ...