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Gupta, Uday K.

Publications and source records attributed to Gupta, Uday K..

Method and system for reducing metadata overhead in a two-tier storage architecture

Example embodiments of the present invention relate to a method, a system, and a computer program product for maintaining dynamically loadable namespaces. The method includes presenting, to an application, a file system having a global single namespace (SN) comprising a plurality of dynamically-loadable namespaces (DLNs) maintained in a capacity tier (CT) of object storage of a storage system. In response to a job submitted by the application, dynamically loading a first dynamically-loadable namespace, including the metadata only for the first dynamically-loadable namespace, associated with the job from the capacity tier of object storage into a fast tier (FT) of storage of the storage system.

97 MATHEMATICS AND COMPUTING↗

Identification and interpretation of patterns in rocket engine data: Artificial intelligence and neural network approaches

This paper describes an expert system which is designed to perform automatic data analysis, identify anomalous events, and determine the characteristic features of these events. We have employed both artificial intelligence and neural net approaches in the design of this expert system. The artificial intelligence approach is useful because it provides (1) the use of human experts' knowledge of sensor behavior and faulty engine conditions in interpreting data; (2) the use of engine design knowledge and physical sensor locations in establishing relationships among the events of multiple sensors; (3) the use of stored analysis of past data of faulty engine conditions; and (4) the use of knowledge-based reasoning in distinguishing sensor failure from actual faults. The neural network approach appears promising because neural nets (1) can be trained on extremely noisy data and produce classifications which are more robust under noisy conditions than other classification techniques; (2) avoid the necessity of noise removal by digital filtering and therefore avoid the need to make assumptions about frequency bands or other signal characteristics of anomalous behavior; (3) can, in effect, generate their own feature detectors based on the characteristics of the sensor data used in training; and (4) are inherently parallel and therefore are potentially implementable in special-purpose parallel hardware.

Ali, Moonis↗