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The design of a stable slope in a rock mass environment is a quite complicated job due to the anisotropic behaviour of the rock mass. In this research work, the cut slopes at the Swat motorway in the weakest schist rock is numerically analyzed by the shear strength reduction (SSR) approach using the Finite Element-based 2D RS2 software. The slope is divided into two cases according to the nature of the rock. Each case of the cut slope is analyzed by two stabilization methods 1) changing the characteristics of the slope 2) support system installation based on the Mohr-Coulomb (MCC) and Generalized Hoek and Brown (GHB) failure criteria in order to propose the most appropriate method for slope stabilization. The results obtained reveal that the Critical Strength Reduction Factor (CSRF) before applying the stabilization methods is 1.34 (MCC) and 1.04 (GHB) for Case-I and 1.21 (MCC) and 0.53 (GHB) for Case-II. CSRF for Case-I after changing the characteristics of the slope is observed to be 2.43 (MCC) and 2.33 (GHB), while for Case-II is 1.82 (MCC) and 1.26 (GHB), respectively. CSRF for Case-I after the support installation criteria is 1.59 (MCC) and 1.07 (GHB), while for Case-II is 1.65 (MCC) and 0.5 (GHB), respectively. Based on the comparative analysis, it is revealed that changing the characteristics of the slope method shows prominent results in both cases; therefore, this method can be effectively used in order to stabilize the slope in the weakest rock mass environment.

Dosimetry audits have an important role to safely deliver the prescribed radiation dose to the cancerous area.  It not only maintains and improve the treatment standards but also identify issues that are potentially harmful to the patients. This article presents the results of a comparative study of beam output measurements of a high-energy photon beam emitted from a medical linear accelerator.

The measurements were performed by an International Atomic Energy Commission (IAEA) Quality Assurance/Quality Control survey mission (level-I dosimetry), a national Secondary Standard Dosimetry Laboratory (SSDL) experts (level-II dosimetry) and hospital physicists (level-III dosimetry). Glass dosimeters and cylindrical ionization chambers for level I and cylindrical ionization chambers for level-II and -III dosimetry were used in water by following IAEA TRS-398 protocol.

The level-I dosimetry results of glass dosimeters and ionization chambers were compared and percent deviations of -0.4 % and 0.3 % were found for 6 and 15 MV-photon beams, respectively. Similarly, level-II and -III dosimetry results with respect to level-I are in good agreement and within the optimum uncertainty level of ±5%. The annual level-II dosimetry quality audits (i.e., from 2010 to 2015) showed that only one dosimetry audit is out of the optimum level set for this study. However, it is within the tolerance level set for level-II quality audit programs (i.e., < ±5%).

In conclusion, this article has demonstrated consistent radiotherapy radiation dosimetry results for MV-photons beams. It also showed quantitative information in-line with the currently achieved accuracy and precision of external megavoltage photon beam dosimetry. Furthermore, this study also established a baseline for current routine audits of radiotherapy dosimetry. Studies of this type are essential to appropriately follow the recommendations and procedures of the pertinent dosimetry protocols.

This paper intended to examine the impact of solar electrification on education attainment in rural areas of Bajaur Agency. The household survey was conducted by using a recall method for collecting the primary data through structured questionnaire. The data was analysed through regression model as well as through descriptive statistics. The solar energy has provided direct and indirect benefits to the plotted households in the study area of Bajaur Agency, Pakistan. The result reveals that, the study hours of students had increased after the installation of solar energy system. There was significant improvement in social activities which were earlier limited to day time. Moreover, a slight increase in income activities was also noticed due to increase in working hours. Thus, solar energy has improved the study hours and had a direct impact on human capital of the rural households. So, it is viable system and should be extended to such other inaccessible communities.