This paper presents a novel method for performing the registration and gamma correction of images in a simultaneous manner. The image registration and relative gamma estimation problems are formulated such that both problems are solved at the same time by solving a single minimum squared distance problem. The proposed method utilizes the Fast Fourier Transform (FFT) to solve the combined regist...

The Panoramic Dental X-ray image is an important tool for a thorough dental examination. These X-ray images suffer from poor contrast because of the luminance non-linearity introduced by medical imaging techniques. Hence an automatic method of image enhancement of panoramic X-ray image is essential. A novel method of improving the quality of these images is determined based on gamma correction ...

As an efficient image contrast enhancement (CE) tool, adaptive gamma correction (AGC) was previously proposed by relating gamma parameter with cumulative distribution function (CDF) of the pixel gray levels within an image. ACG deals well with most dimmed images, but fails for globally bright images and the dimmed images with local bright regions. Such two categories of brightness-distorted ima...

Almost all the X-ray afterglows of gamma-ray bursts (GRBs) observed by the Swift satellite have a shallow decay phase in the first thousands of seconds. We show that in an inhomogeneous jet (multiple-subjet or patchy-shell) model the superposition of the afterglows of off-axis subjets (patchy shells) can have the shallow decay phase. The necessary condition for obtaining the shallow decay phase...

introduction: scatter radiation is one of the major sources of error in nuclear medicine data processing. different methods of scatter correction have been introduced in order to improve the quality of data. however the best method is to avoid recording of scatter photons in acquisition. the only difference between scattered and non-scattered photons is the energy. pulse height analyzer is the ...

The decay of fission fragments is studied through Monte Carlo Hauser-Feshbach model calculations taking into account the competition between the emissions of prompt fission neutrons and gamma rays. The importance of initial excitation energy and spin distribution in the primary light and heavy fragments is demonstrated through comparison with experimental data. Excitation energy sorting mechani...

An improved method for visual gamma correction is developed for LCD displays to increase the accuracy of digital colour reproduction. Rather than utilising a photometric measurement device, we use observers’ visual luminance judgements for gamma correction. Eight half tone patterns were designed to generate relative luminances from 1/9 to 8/9 for each colour channel. A psychophysical experiment...

Taking into account the recent suggestion that a short gamma-ray burst (GRB) looks like the first 1 sec of a long GRB, we propose that the jet of a GRB consists of multiple sub-jets or sub-shells (i.e., an inhomogeneous jet model). The multiplicity of the sub-jets along a line of sight ns is an important parameter. If ns is large (≫ 1) the event looks like a long GRB, while if ns is small (∼ 1)...

The two-parameter Poisson-Dirichlet distribution is the law of a sequence of decreasing nonnegative random variables with total sum one. It can be constructed from stable and Gamma subordinators with the two-parameters, α and θ, corresponding to the stable component and Gamma component respectively. The moderate deviation principles are established for the two-parameter Poisson-Dirichlet distri...

There is an abundant literature on inequalities for the (Euler’s) Gamma function C and its various related functions. Yet, only very recently, several authors began to study inequalities for the (Barnes’) double Gamma function C2. Here, in this paper, we aim at presenting several two-sided inequalities for the multiple Gamma functions Cn ðn 1⁄4 2; 3; 4; 5Þ. In our investigation of these two-sid...