14,149 research outputs found

    Sprayable birefringent coating enables strain measurements on large surfaces

    Get PDF
    Birefringent coating for strain measurements on large surfaces contains constituents that can be premixed and sprayed as a single component with conventional paint spray equipment. Elevated temperatures are not required for spraying or curing of the coating material which has long pot life

    An overview of the DOE terrestrial crystalline solar cell research program

    Get PDF
    There has been significant progress in the crystalline solar cell area in the past two years that has rejuvenated interest in the high efficiency devices for terrestrial photovoltaic systems. The most significant developments have been in the crystalline solar cell area, but progress in the III-V area has also been recorded. A review of terrestrial crystalline cell research is presented along with a description of future research directions

    VHF command system study

    Get PDF
    Solutions are provided to specific problems arising in the GSFC VHF-PSK and VHF-FSK Command Systems in support of establishment and maintenance of Data Systems Standards. Signal structures which incorporate transmission on the uplink of a clock along with the PSK or FSK data are considered. Strategies are developed for allocating power between the clock and data, and spectral analyses are performed. Bit error probability and other probabilities pertinent to correct transmission of command messages are calculated. Biphase PCM/PM and PCM/FM are considered as candidate modulation techniques on the telemetry downlink, with application to command verification. Comparative performance of PCM/PM and PSK systems is given special attention, including implementation considerations. Gain in bit error performance due to coding is also considered

    A comparison of the radiation tolerance characteristics of multijunction solar cells with series and voltage-matched configurations

    Get PDF
    The effect of series and voltage-matched configurations on the performance of multijunction solar cells in a radiation environment was investigated. It was found that the configuration of the multijunction solar cell can have a significant impact on its radiation tolerance characteristics

    A comparison of the radiation tolerance characteristics of multijunction solar cells with series and voltage-matched configurations

    Get PDF
    The effect of series and voltage-matched configurations on the performance of multijunction solar cells in a radiation environment was investigated. It was found that the configuration of the multijunction solar cell can have a significant impact on its radiation tolerence characteristics

    The effect of different module configurations on the radiation tolerance of multijunction solar cells

    Get PDF
    The effect of different module configurations on the performance of multijunction (MJ) solar cells in a radiation environment was investigated. Module configuration refers to the electrical circuit in which the subcells of the multijunction cell are wired. Experimental data for AlCaAs, GaAs, InGaAs, and silicon single-junction concentrator cells subjected to 1 MeV electron irradiation was used to calculate the expected performance of AlGaAs/InGaAs, AlGa/silicon, GaAs/InGaAs, and GaAs/silicon Mj concentrator cells. These calculations included independent, series, and voltage-matched configurations. The module configuration was found to have a significant impact on the radiation tolerance characteristic of the MJ cells

    Ethnic Inequality in Canada: Economic and Health Dimensions

    Get PDF
    This study examines ethnic based differences in economic and health status. We combine existing literature with our analysis of data from the Canadian Census and National Population Health Survey. If a given sub-topic is well researched, we summarize the findings; if, on the other hand, less is known, we present data placing them in the context of whatever literature does exist. Our findings are consistent with existing literature on ethnic inequalities in Canada. Recent immigrants with a mother tongue other than English or French are among the most economically disadvantaged in Canadian society, though the results vary depending on gender and ethnic background. In fact economic inequality according to type of occupation can be attributed to gender rather than ethnicity; that is, the Canadian labour force continues to be more gender- than ethnically-differentiated. Yet recent immigrants, especially from Asia, are advantaged in health outcomes compared to Canadian-born persons – the “healthy immigrant” effect. Interestingly they are less likely to report having a physical check-up and, for women (especially Asian-born women), a mammogram within the last year compared to their Canadian-born counterparts. Given the significance of both gender and ethnicity as predictors of well-being, future research should examine the intersection between the two identity markers and their relationship to social inequality.ethnicity, immigration, language, gender, income, occupation, health

    Development of optical data processing techniques applicable to detection and study of meteor trails

    Get PDF
    Development of coherent optical data processing techniques applicable to detection of meteor trails and examination of propertie
    corecore