4 resultados para 329-U1371F
em Greenwich Academic Literature Archive - UK
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This paper details a modelling approach for assessing the in-service (field) reliability and thermal fatigue life-time of electronic package interconnects for components used in the assembly of an aerospace system. The Finite Element slice model of a Plastic Ball Grid Array (PBGA) package and suitable energy based damage models for crack length predictions are used in this study. Thermal fatigue damage induced in tin-lead solder joints are investigated by simulating the crack growth process under a set of prescribed field temperature profiles that cover the period of operational life. The overall crack length in the solder joint for all different thermal profiles and number of cycles for each profile is predicted using a superposition technique. The effect of using an underfill is also presented. A procedure for verifying the field lifetime predictions for the electronic package by using reliability assessment under Accelerated Thermal Cycle (ATC) testing is also briefly outlined.
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Time-series and sequences are important patterns in data mining. Based on an ontology of time-elements, this paper presents a formal characterization of time-series and state-sequences, where a state denotes a collection of data whose validation is dependent on time. While a time-series is formalized as a vector of time-elements temporally ordered one after another, a state-sequence is denoted as a list of states correspondingly ordered by a time-series. In general, a time-series and a state-sequence can be incomplete in various ways. This leads to the distinction between complete and incomplete time-series, and between complete and incomplete state-sequences, which allows the expression of both absolute and relative temporal knowledge in data mining.
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Global branding brings with it exposure to an increasingly culturally-diverse audience. Examples of Islamic finance products being consumed by non-Muslims, and designer labels being adopted, by those outside of their intended target audience; seem to suggest that brands are being shaped more and more by consumers. Within current literature on branding, and cross-cultural consumer behaviour; there appears to have emerged a difference of opinion - as to whether a consumer’s culture has any bearing on their decision making; or subsequent influence brand personalities. The purpose of this paper is to present existing evidence; as a basis for undertaking future research.