For small devices like the PDAs and mobile phones, formulation of relational database queries is not as simple as using conventional devices such as the personal computers and laptops. Due to the restricted size and r...For small devices like the PDAs and mobile phones, formulation of relational database queries is not as simple as using conventional devices such as the personal computers and laptops. Due to the restricted size and resources of these smaller devices, current works mostly limit the queries that can be posed by users by having them predetermined by the developers. This limits the capability of these devices in supporting robust queries. Hence, this paper proposes a universal relation based database querying language which is targeted for small devices. The language allows formulation of relational database queries that uses minimal query terms. The formulation of the language and its structure will be described and usability test results will be presented to support the effectiveness of the language.展开更多
Today reliability is one of the serious requirements of electronic systems. The numbers of system failures, repair cost, guarantee, etc. are estimated by reliability estimation. In this paper reliability of a switchin...Today reliability is one of the serious requirements of electronic systems. The numbers of system failures, repair cost, guarantee, etc. are estimated by reliability estimation. In this paper reliability of a switching power supply, which is used for personal computers, is evaluated. It will show that the most of failure rates depends on power circuit because of more stresses and dissipations. Derating effect of devices on the failure rate is discussed. A prototype power supply＇s waveforms are used for stress detection and calculation of dissipations.展开更多
文摘For small devices like the PDAs and mobile phones, formulation of relational database queries is not as simple as using conventional devices such as the personal computers and laptops. Due to the restricted size and resources of these smaller devices, current works mostly limit the queries that can be posed by users by having them predetermined by the developers. This limits the capability of these devices in supporting robust queries. Hence, this paper proposes a universal relation based database querying language which is targeted for small devices. The language allows formulation of relational database queries that uses minimal query terms. The formulation of the language and its structure will be described and usability test results will be presented to support the effectiveness of the language.
文摘Today reliability is one of the serious requirements of electronic systems. The numbers of system failures, repair cost, guarantee, etc. are estimated by reliability estimation. In this paper reliability of a switching power supply, which is used for personal computers, is evaluated. It will show that the most of failure rates depends on power circuit because of more stresses and dissipations. Derating effect of devices on the failure rate is discussed. A prototype power supply＇s waveforms are used for stress detection and calculation of dissipations.
