A Brief Review for Semiconductor Memory Testing Based on BIST Techniques

With rapid growth of semiconductor industry and increase in complexity of semiconductor based memory, necessity of stringent testing methodology has become one of top most criteria for memory evaluation. This paper describes the fundamental concepts and overview of Built-In-Self-Test (BIST). It describes different functional faults modeling of RAM and flash memory. This review mentions about testing approaches for memory and illustrates BIST techniques for finding faults, power dissipation, area overhead and test time during testing, also includes research gap and future scope regarding the testing of memory.

Signature-based detection of behavioural deviations in flight simulators - Experiments on FlightGear and JSBSim

Flight simulators are systems composed of numerous off-the-shelf components that allow pilots and maintenance crew to prepare for common and emergency flight procedures for a given aircraft model. A simulator must follow severe safety specifications to guarantee correct behaviour and requires an extensive series of prolonged manual tests to identify bugs or safety issues. In order to reduce the time required to test a new simulator version, this paper presents rule-based models able to automatically identify unexpected behaviour (deviations). The models represent signature trends in the behaviour of a successful simulator version that are compared to the behaviour of a new simulator version. Empirical analysis on nine types of injected faults in the popular FlightGear and JSBSim open source simulators shows that our approach does not miss any deviating behaviour considering faults which change the flight environment, and that we are able to find all the injected deviations in 4 out 7 functional faults and 75% of the deviations in 2 other faults.

Signature-based detection of behavioural deviations in flight simulators - Experiments on FlightGear and JSBSim

Flight simulators are systems composed of numerous off-the-shelf components that allow pilots and maintenance crew to prepare for common and emergency flight procedures for a given aircraft model. A simulator must follow severe safety specifications to guarantee correct behaviour and requires an extensive series of prolonged manual tests to identify bugs or safety issues. In order to reduce the time required to test a new simulator version, this paper presents rule-based models able to automatically identify unexpected behaviour (deviations). The models represent signature trends in the behaviour of a successful simulator version that are compared to the behaviour of a new simulator version. Empirical analysis on nine types of injected faults in the popular FlightGear and JSBSim open source simulators shows that our approach does not miss any deviating behaviour considering faults which change the flight environment, and that we are able to find all the injected deviations in 4 out 7 functional faults and 75% of the deviations in 2 other faults.

Defect Feature Acquisition of LED Wafer Using Region Growing Segmentation with Clustering Strategy

The defects of LED wafer may be caused from the manufacturing environments such as contamination. The appearance of the defects can results in functional faults of LED wafer. Therefore, it is very necessary to detect the defects in LED wafer. In this paper, a new method is presented for the defect feature acquisition of LED wafer, the method uses region growing to segment the LED wafer image in order to acquire the defect features. The clustering strategy is added to the region growing for enhancing the acquisition precision of defect features. The defect features that have been obtained can be used to detect these defects of LED wafer. The method consists of following two steps. First of all, the original image of LED wafer is partitioned into several sub-blocks that are not overlapped, and then these sub-blocks are segmented by clustering strategy. Secondly, the whole wafer image is segmented by using region growing algorithm.