In this paper, we use vertically invariant morphological filters for time-varying or adaptive signal processing. The morphological filters adopted in this paper are vertically invariant openings and closings. Vertically invariant openings and closings have intuitive geometric interpretations and can provide different filtering scales with respect to different spacial positions. Hence, they are ...

This paper deals with the problem of identifying effective occluders for visibility culling. The solid-angle metric is commonly used for measuring the potential significance of occluders from a single viewpoint. In this paper, we show that it does not extend properly to from-region occlusion calculations. We propose to measure the effectiveness of an occluder by means of the size of its umbra. ...

This paper introduces a new concept within shadow segmentation for usage in shadow removal and augmentation through construction of an alpha overlay shadow model. Previously, an image was considered to consist of shadow and non-shadow regions. We construct a model that accounts for sunlit, umbra and penumbra regions. The model is based on theories about color constancy, daylight, and the geomet...

Shadow detection in real scene images is always a challenging but yet interesting area. Most shadow detection and segmentation methods are based on image analysis. This paper aimed to give a comprehensive and critical study of current shadow detection methods. Various approaches have been discussed related to shadow detection in images. The principles of these methods rely on intensity differen...

The Neotropical genus SchacontiaDyar (1914) is reviewed and revised to include eleven species. Schacontia replica Dyar, 1914, syn. n. and Schacontia pfeifferi Amsel, 1956, syn. n. are synonymized with Schacontia chanesalis (Druce, 1899) and eight new species are described: Schacontia umbra,sp. n., Schacontia speciosa,sp. n., Schacontia themis, sp. n., Schacontia rasa, sp. n., Schacontia nyx,sp....

Nothobranchius rachowi, a tropical fish that belongs to the family of the Cyprinodontidae, is introduced as a new animal for genetic toxicological studies. The karyotype of N. rachowi consists of 16 large chromosomes. This species can be used for studies on chromosomal aberrations as well as for observations on sister-chromatid exchanges (SCEs). Exposure to 120 mg ethyl methanesulphonate per li...

Oscillations in stomatal resistance to viscous air flow have been recorded in the juvenile and adult sclerophylls of Eucalyptus umbra R. T. Baker, in both controlled and natural environments. Under constant illumination, temperature, and humidity, irregular oscillations in stomatal resistance with a periodicity of approximately 20 to 30 minutes occurred spontaneously, when the soil water potent...

Abstract We present a detailed study of very strong magnetic fields in the NOAA Active Region (AR) 12673, which was most flare productive AR solar cycle 24. It produced four X-class flares including X9.3 on 2017 September 6 and X8.2 limb event 10. Our analysis is based direct measurements full Zeeman splitting Fe i 1564.85 nm line using all Stokes I, Q, U, V profiles. This approach allowed us t...

Kodaikanal Solar Observatory (KoSO) possesses one of world's longest and homogeneous records sunspot observations that span more than a century (1904-2017). Interestingly, these (originally recorded in photographic plates/films) were taken with the same setup over this entire time period which makes data unique best suitable for long-term solar variability studies. A large part data, between 19...