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To help the prospective observer take full advantage of the mid-IR capability of Gemini South, we characterize a key aspect of the mid-IR performance of the 8-meter telescope at Gemini-S, namely, the appearance and stability of its delivered mid-IR image profiles, with the goal of demonstrating that it can be used with a level of precision not used before. About 2000 images obtained with T-ReCS (a facility mid-IR camera at Gemini-S) between late 2003 and early 2009 were used for our image quality analysis. All targets are flux standards and recorded at one or more of the four bands Si-2 (8.74 μm), N (10.36 μm), Si-5 (11.66 μm), and Qa (18.3 μm). A non-linear least squares fitting of three profile models (Lorentzian, Gaussian, and Moffat) was performed on each image, and key parameters such as FWHM, ellipticity, position angle and Strehl-ratio were measured from the fitted profile. We find that the long-time-scale image quality is quite stable in terms of profile width or ellipticity, though short-time-scale variation is evident. We also examined the correlation between image quality and many ambient parameters and confirmed the interdependence between the image quality in the Qa band and the ambient humidity. The ellipticity of the profile was analyzed statistically as well. The average profiles for different filters can be used as important references in the future when a high-quality profile reference is not available during an observation.

The reaction time to the occurrence of unexpected events is essential in night-time driving which uses thermal cameras and EMCCD cameras. The present work analyses the implications of monochrome and coloured observation, of in-depth perception of the distance field, of visual accuracy of the display characteristics that the image is shown on, and of the detection matrices corresponding to the two cameras. The paper also looks at the significant impact of the ambient humidity on the fatigue increase due to prolonged observation. The study also contains a comparative analysis of the observation with, and without a reticle in the evaluation of distance elements from the observed scene. The experiments the present study is based on have been realised using a simulation software in LabVIEW. The work presents also particular case studies to be used in the practical analysis of the reaction time to the driving of vehicles and monitoring their traffic during day or night, with the display of the image on LCD. The experiments were based on films acquired in different ambient conditions, with clear atmosphere, with fog or snowing.

Manufacturers of PV-modules usually give a warranty for at least 20 years. There is still only little knowledge about the lifetime of newly developed modules, however. How do they cope with snow, desert-climate or tropical humidity? In order to answer this question the Fraunhofer-Institute for Solar Energy Systems and TUV Rheinland have installed different outdoor exposure sites where modules have to stand extreme climates: high temperatures with high differences between day and night in the Negev desert at Israel, snow, wind and changing irradiation in the German Alps, and high humidity at warm temperatures at Indonesia. Commercial modules from industrial partners as well as innovative modules with different combinations of encapsulants and back-sheets were exposed. UV-irradiation, solar-irradiation, ambient- and module temperatures, ambient humidity and wind speed is measured and collected at a central server in Germany. These data are the basis for the calculation of integral loads for the comparison of different climatic regions and for an estimation of the service life, an exciting field of work since decades 1,2,3 . Results from the evaluation of the monitoring during the fist 12 months of exposure are compared. Fluorescent lamps are chosen for accelerated UV-testing, since they simulate the UV-irradiation of the sun well while emitting less thermal radiation than Xenon-lamps. The UV-source is designed for use in climatic cabinets for damp-heat testing with UV.

Recent studies have shown spray cooling of the skin surface with millisecond cryogen spurts to be an effective method for protecting the epidermis from non-specific thermal injury during various laser mediated dermatological procedures. We have investigated the effects of ambient humidity level, spraying distance, and cryogen boiling point on the resulting radiometric surface temperature. Our findings indicate that: (1) decreasing the ambient humidity level results in less ice formation on the skin surface without altering the radiometric surface temperature during a cryogen spurt; (2) increasing the spraying distance to 85 mm lowers the radiometric surface temperature; and (3) boiling point of the cryogen does not directly affect the surface temperature in the geometries studied.