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There are four main processes involved during the reconstruction of bitmap images, which include boundary detection, corner points detection, parameterization and curve fitting. This paper presents the use of Artificial Bee Colony (ABC) algorithm during the process of parameterization and cubic Bézier curve was used for the reconstruction of generic shapes by using Least Square method. Since the purpose of this study is to minimize the distance between boundary of the original image and parametric curve, Sum Square Error (SSE) has been used to calculate the error given by these two curves. The results obtained by using ABC algorithm will be compared with the results obtained when using chord length method during the parameterization process. Note that, for the comparison purpose, the same images have been used and the procedure remains the same except for parameterization process. The finding of this study illustrates that the proposed method has successfully generated fitted cubic Bézier curve that resembles the boundary of original images and enhances its performance since it produces a small error as compared to the result obtained by using chord length parameterization method. [ABSTRACT FROM AUTHOR]

The Interface Region Imaging Spectrograph (IRIS) reveals numerous small-scale (sub-arcsecond) brightenings that appear as bright dots sparkling the solar transition region in active regions. Here, we report a statistical study on these transition-region bright dots. We use an automatic approach to identify 2742 dots in a Si IV raster image. We find that the average spatial size of the dots is 0.8 arcsec2 and most of them are located in the faculae area. Their Doppler velocities obtained from the Si IV 1394 Å line range from -20 to 20 km s-1. Among these 2742 dots, 1224 are predominantly blue-shifted and 1518 are red-shifted. Their non-thermal velocities range from 4 to 50 km s-1 with an average of 24 km s-1. We speculate that the bright dots studied here are small-scale impulsive energetic events that can heat the active region corona. [ABSTRACT FROM AUTHOR]

To date, differing implementations of continuous scan laser Doppler vibrometry have been demonstrated by various academic institutions, but since the scan paths were defined using step or sine functions from function generators, the paths were typically limited to 1D line scans or 2D areas such as raster paths or Lissajous trajectories. The excitation was previously often limited to a single frequency due to the specific signal processing performed to convert the scan data into an ODS. In this paper, a configuration of continuous-scan laser Doppler vibrometry is demonstrated which permits scanning of arbitrary areas, with the benefit of allowing multi-frequency/broadband excitation. Various means of generating scan paths to inspect arbitrary areas are discussed and demonstrated. Further, full 3D vibration capture is demonstrated by the addition of a range-finding facility to the described configuration, and iteratively relocating a single scanning laser head. Here, the range-finding facility was provided by a Microsoft Kinect, an inexpensive piece of consumer electronics. [ABSTRACT FROM AUTHOR]