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[en] The characteristic interval plays a vital role on the existence of iterative roots of PM functions with height less than or equal to one. In this paper, we define the characteristic interval for continuous functions and prove theorems on extension and nonexistence of iterative roots for a class of continuous non-PM functions on a closed and bounded interval I. Also, we prove that a class of continuous non-PM functions, which do not possess any iterative roots, is dense in C(I, I).
[en] We present a sample of 17 newly discovered ultracool dwarf candidates later than ∼M8, drawn from 231.90 arcmin2 of Hubble Space Telescope Wide Field Camera 3 infrared imaging. By comparing the observed number counts for 17.5 ≤ J125 ≤ 25.5 AB mag to an exponential disk model, we estimate a vertical scale height of zscl = 290 ± 25 (random) ± 31 (systematic) pc for a binarity fraction of fb = 0. While our estimate is roughly consistent with published results, we suggest that the differences can be attributed to sample properties, with the present sample containing far more substellar objects than previous work. We predict the object counts should peak at J125 ∼ 24 AB mag due to the exponentially declining number density at the edge of the disk. We conclude by arguing that trend in scale height with spectral type may breakdown for brown dwarfs since they do not settle onto the main sequence.
[en] The proposed method is an expansion of the summation method for doublets of peaks with equal width. The mutual influence of the peaks is taken into account by a correction function depending on the response function of the spectrometer. A particular application is the evaluation of routine measurements, where similar spectra are recorded at high rates without changing the electronic adjustment. The method is restricted to doublets with a mutual distance of more than 1.5 fwhm and an intensity ratio down to about 1:10. (Auth.)
[en] A statistical investigation was made of the height of prominences observed at Lomnicky Stit coronal station throughout the years 1967 to 1986. It was shown that the prominence height law distribution depended on the phase of the solar activity cycle. The height of polar prominences during cycle changed more than that of the prominences in the main zone. (author). 4 figs., 6 tabs., 24 refs
[en] Generalized Morse wavelets are proposed to evaluate the phase information from projected fringe pattern with the spatial carrier frequency in the x direction. The height profile of the object is determined through the phase change distribution by using the phase of the continuous wavelet transform. The choice of an appropriate mother wavelet is an important step for the calculation of phase. As a mother wavelet, zero order generalized Morse wavelet is chosen because of the flexible spatial and frequency localization property, and it is exactly analytic. Experimental results for the Morlet and Paul wavelets are compared with the results of generalized Morse wavelets analysis. (paper)
[en] Two global models (HadAM3: The Hadley Centre Atmospheric Model version 3 and CAM3: The Community Atmospheric model version 3) have been studied regarding their capabilities in reproducing the small scale features over southern Africa compared with the NCEP reanalysis. In this study, geopotential height at 500hPa and 850hPa pressure levels are used to investigate the variability of small scale circulation features over southern Africa. The investigation took into consideration the magnitude of the models standard deviations. Most of the results were linked with rainfall and temperature over the region. It was found that the standardized anomalies in the geopotential height at the 500hPa pressure level are in phase with that of rainfall. In contrast, the standardized anomalies of 850hPa pressure level geopotential height are out of phase with the standardized anomalies of rainfall and temperature. In addition, the models are able to capture the variation in the mean cut-off lows, number of days with deep tropical lows and number of days with Tropical Temperate Troughs (TTTs) quite well. However, the models could not capture the number of days with temperate lows very well. Generally, the models are able to reproduce the synoptic scale circulation features which are crucial for reliable seasonal forecast over southern Africa. (author)
[en] The method of pointing and measuring any heights of trunks is based on the theory of the similar triangle. The new apparatus, that is able to point and measure any heights of trunk, is constituted of the red-laser-pointer that is able to move vertically on the observing point, the horizontal-scale that is able to lengthen or shorten its length as 1/100 distance from the observing point to measuring trees, and the vertical-object-scale that has thin horizontal-frames every centimeter as a ladder. When the length of horizontal-scale is adjusted to 1/100 distance from the observing point to the measuring tree, and when the laser-beam is radiated through observing point to the measuring tree, through nearly upper (or under) edge of the thin horizontal-frames of the vertical-object-scale, the any numbers of the thin horizontal-frames of the vertical-object-scale that are radiated by the red-laser-pointer are equal to the meter-lengths of the trunk of the measuring tree. And then the upper diameters that are pointed by the red-laser-pointer can be measured from the remote points as the same distance between two other parallel beams of the two red-laser-pointers that are attached on the remote calipers instead of its arms
[en] We study the dynamics of the meniscus rise of a liquid contained in a narrow gap between a flexible film and a solid wall. We show that the meniscus rises indefinitely expelling liquid from the gap region, and that the height of the rising front h(t) increases with time as , while the gap distance e(t) decreases as . These results are consistent with the experiments of Cambau et al. (EPL, 96 (2011) 24001). (letter)
[en] We propose dual-detection confocal reflectance microscopy (DDCRM) for high-speed 3D surface profiling. In comparison with conventional confocal microscopy, DDCRM can realize surface profiling without axial scanning. DDCRM is composed of two point detectors, each with a pinhole of different size. The ratio of the axial response curves measured by the two detectors provides the relationship between the axial position of the sample and the ratio of the intensity signals. Furthermore, DDCRM has a normalizing effect which allows this method to accurately measure the height of samples with various reflectance characteristics. (paper)