In the present paper, the dechanneling and the energy loss of protons at the energy interval of 1400 to 2200 keV along the {100} and the {110} planar directions of Si were studied by the simulation of the measured channeling Rutherford back-scattering spectra based on the exponential dechanneling function with a parameter λ. This parameter is proportional to the dechanneling rate and represents the mean distance that ions travel along the channel before escaping from the channel. The Levenberg-Marquardt algorithm was used to set the best values of the channeling to random energy loss ratio, and the mean channeling distance. The experimental results are well reproduced by this simulation. The data analyzed in this energy range did not show any particular trend with regard to energy dependence of the parameters. The differences between both the planar channels in the Si crystal and their influence on the energy loss ratio and dechanneling of proton ions are described.

In this paper, the effect of the potential barrier and open area of Silicon along the crystallographic direction <100> and <110> on the channeling stopping power and the channeling half- distance for protons are investigated. The channeling stopping power and the channeling half- distance for protons are measured by simulation of the channeling spectra in the energy range of Ep=1800-2200keV. It is assumed that the dechanneling process behaves exponentially. It showed that the channeling stopping power for protons decreases when the potential barrier and open area of channel increase. Furthermore, the channeling half- distance increases by increasing the open area of the channel.

In this paper, a novel risk-based, two-objective (technical and economical) optimal reactive power dispatch method in a wind-integrated power system is proposed which is more consistent with operational criteria.  The technical objective includes the minimization of the new voltage instability risk index. The economical objective includes cost minimization of reactive power generation and active power loss. The proposed voltage instability risk employs a hybrid possibilistic (Delphi-Fuzzy)-probabilistic approach that takes into consideration the operator’s experience, the wind speed and demand forecast uncertainties when quantifying the risk index. The decision variables are the reactive power resources of the system. To solve the problem, the modified multi-objective particle swarm optimization algorithm with sine and cosine acceleration coefficients is utilized. The method is implemented on the modified IEEE 30-bus system. The proposed method is compared with those in the previously published literature, and the results confirm that the proposed risk index is better at estimating the voltage instability risk of the system, especially in cases with severe impact and low probability. In addition, according to the simulation results compared to typical security-based planning, the proposed risk-based planning may increase the security and economy of the system due to better utilization of system resources.

The Ion Beam Techniques have opened a new window to study crystal structures and imperfections of crystals. In this paper, we try to briefly describe concepts and applications of RES-Channeling to determine crystal parameters and disorders. Some experimental results of the analysis of semiconductor materials are presented in this paper, which has been obtained by means of RES-Channeling technique.

Calculation of stopping power and range of different ions is extremely important due to their special importance at controversy of shielding and health physics. Although the so-called Bethe-Bloch relationship describes well how to reduce the energy of particles, the difference in the interaction mechanisms of ions and light and heavy particles in a wide range of energy values causes that the accurate estimation of this relationship requires various corrections. In this article, in order to simulate stopping power changes in terms of proton inclining beam energy with different ions, artificial neural network and multilayer perceptron techniques will be used. And high efficiency of suggested way for stopping power and range and valid artificial model are achieved by comparing results of the neural network with results of calculating SRIM code and also available experimental data.

We calculate the stopping power for heavy-ion diclusters moving in a strongly coupled two-dimensional electron gas system by using the local field corrected dielectric function at finite temperature. We obtain a parameterized local field correction factor based on a relation between the thermal compressibility and exchange-correlation energy in two-dimension. The interpolated parameter is derived from the Monte-Carlo data for the exchange-correlation energy of a two-dimensional electron gas system. We compare our results with those of previous calculations which used a local field factor that satisfied the compressibility sum rule in three-dimension. In general, the stopping power increases by taking into account the short-range interactions. In addition, it is found that the dicluster stopping power (in particular the uncorrelated part) obtained from our calculations is smaller than the previous work.

Due to the vital role of back channels in mutual understanding and their use in many aspects of language learning, the present study investigated the attitudes toward back-channeling in Iranian EFL online versus regular classes. The study was quasi-experimental in design, with interviews and recording of course sessions by ZDF Soft Screen Recorder and the voice Memos application in both classes to measure the duration of silence, TTT (Teacher Talk Time), STT (Student Talk Time), BC (Back Channels), and other activities such as TCS (Teachers' Code-Switching), SCS (Students’ Code-Witching), S (the time passed in silence). In doing so, two online classes included 30, two regular ones included 27, and four English teachers of the participants were randomly selected from the Kanoon Language Institute in Isfahan, Iran, to take part in the study. Learners received four and a half hours of instruction per week within the course period. In the next step, all the data gathered was analyzed and statistically addressed by using, IBM SPSS Statistics (Version 26) software. The results revealed back channels had positive effects on learners in both classes. Besides, teachers and learners had positive attitudes toward using back channels, however, in online classes, learners were more willing to use back channels. The findings of this study could be fruitful for improvement with well-designed materials and explicitly teaching back channels, which can provide opportunities for learners to express their emotions, and ideas, and enhance their strengths.