Dynamics of a Charged Particle Around a Slowly Rotating Kerr Black Hole Immersed in Magnetic Field

The dynamics of a charged particle moving around a slowly rotating Kerr black hole in the presence of an external magnetic field is investigated. We are interested to explore the conditions under which the charged particle can escape from the gravitational field of the black hole after colliding with another particle. The escape velocity of the charged particle in the innermost stable circular orbit is calculated. The effective potential and escape velocity of the charged particle with angular momentum in the presence of magnetic field is analyzed. This work serves as an extension of a preceding paper dealing with the Schwarzschild black hole [Zahrani {\it et al}, Phys. Rev. D 87, 084043 (2013)].Comment: 20 pages, 12 figure

Impact of evaluation of the vocational training institutes in the Punjab province, Pakistan

Thesis(Master) -- KDI School: Master of Public Policy, 2021This study examines the impact of the Vocational Training Institutes (VTIs) on employment in the Punjab province, Pakistan. I exploit the difference-in-difference and instrumental variable methods using data from Global Data Lab, Pakistan Board of Statistics (PBS) and Punjab Vocational Training Council (PVTC). I find an increase in the employment rate of Punjab province in response to the implementation of the VTIs. The female employment increased significantly, but the male employment did not increase. I also find no increase in the high-level employment as a falsification test. The results suggest that the vocational training program plays a crucial role in improving labor market outcomes and gender gap in developing countries.1. INTRODUCTION 2. EVALUATION METHODS.. 3. FINDINGS 4. Discussion and Limitations 5. Conclusion 6. Future PlanOutstandingmasterpublishedSaqib HUSSAI

Dynamics of Particles Around a Schwarzschild-like Black Hole in the Presence of Quintessence and Magnetic Field

We investigate the dynamics of a neutral and a charged particle around a static and spherically symmetric black hole in the presence of quintessence matter and external magnetic field. We explore the conditions under which the particle moving around the black hole could escape to infinity after colliding with another particle. The innermost stable circular orbit (ISCO) for the particles are studied in detail. Mainly the dependence of ISCO on dark energy and on the presence of external magnetic field in the vicinity of black hole is discussed. By using the Lyapunov exponent, we compare the stabilities of the orbits of the particles in the presence and absence of dark energy and magnetic field. The expressions for the center of mass energies of the colliding particles near the horizon of the black hole are derived. The effective force on the particles due to dark energy and magnetic field in the vicinity of black hole is also discussed.Comment: 25 pages, 17 figures, accepted for publication in the European Physical Journal

Time Management and Task Prioritization

Time management and task prioritization are major skills and they are especially important for medical students but medical college curricula do not have courses for these topics. This article aims to provide a medical student with some time management techniques that help reduce the work load

Strong Gravitational Lensing by Kiselev Black Hole

We investigate the gravitational lensing scenario due to Schwarzschild-like black hole surrounded by quintessence (Kiselev black hole). We work for the special case of Kiselev black hole where we take the state parameter $w_{q}=-\frac{2}{3}$. For the detailed derivation and analysis of the bending angle involved in the deflection of light, we discuss three special cases of Kiselev black hole: non-extreme, extreme and naked singularity. We also calculate the approximate bending angle and compare it with exact bending angle. We found the relation of bending angles in the decreasing order as: naked singularity, extreme Kiselev black hole, non-extreme Kiselev black hole and Schwarzschild black hole. In the weak field approximation, we compute the position and total magnification of relativistic images as well

Particle Dynamics Around Weakly Magnetized Reissner-Nordstr\"{o}m Black Hole

Considering the geometry of Reissner-Nordstr\"{o}m (RN) black hole immersed in magnetic field we have studied the dynamics of neutral and charged particles. A collision of particles in the inner stable circular orbit is considered and the conditions for the escape of colliding particles from the vicinity of black hole are given. The trajectories of the escaping particle are discussed. Also the velocity required for this escape is calculated. It is observed that there are more than one stable regions if magnetic field is present in the accretion disk of black hole so the stability of ISCO increases in the presence of magnetic field. Effect of magnetic field on the angular motion of neutral and charged particles is observed graphically.Comment: 16 pages, 16 figures, version accepted for publication in 'Advances in High Energy Physics

Evaluation of the Omni-Secure Firewall System in a private cloud environment:Knowledge

This research explores the optimization of firewall systems within private cloud environments, specifically focusing on a 30-day evaluation of the Omni-Secure Firewall. Employing a multi-metric approach, the study introduces an innovative effectiveness metric (E) that amalgamates precision, recall, and redundancy considerations. The evaluation spans various machine learning models, including random forest, support vector machines, neural networks, k-nearest neighbors, decision tree, stochastic gradient descent, naive Bayes, logistic regression, gradient boosting, and AdaBoost. Benchmarking against service level agreement (SLA) metrics showcases the Omni-Secure Firewall’s commendable performance in meeting predefined targets. Noteworthy metrics include acceptable availability, target response time, efficient incident resolution, robust event detection, a low false-positive rate, and zero data-loss incidents, enhancing the system’s reliability and security, as well as user satisfaction. Performance metrics such as prediction latency, CPU usage, and memory consumption further highlight the system’s functionality, efficiency, and scalability within private cloud environments. The introduction of the effectiveness metric (E) provides a holistic assessment based on organizational priorities, considering precision, recall, F1 score, throughput, mitigation time, rule latency, and redundancy. Evaluation across machine learning models reveals variations, with random forest and support vector machines exhibiting notably high accuracy and balanced precision and recall. In conclusion, while the Omni-Secure Firewall System demonstrates potential, inconsistencies across machine learning models underscore the need for optimization. The dynamic nature of private cloud environments necessitates continuous monitoring and adjustment of security systems to fully realize benefits while safeguarding sensitive data and applications. The significance of this study lies in providing insights into optimizing firewall systems for private cloud environments, offering a framework for holistic security assessment and emphasizing the need for robust, reliable firewall systems in the dynamic landscape of private clouds. Study limitations, including the need for real-world validation and exploration of advanced machine learning models, set the stage for future research directions