Role of Social Media in Civic-State Engagement and Political Apathy in New Public Sphere: A Survey of Faculty/Research-Scholars from Gomal & Qurtuba Universities DIK KP Pakistan

Social media [SM] has become a political platform in new public sphere for the politicians, governments and citizens. It is rapidly becoming a popular tool for political and social activism. It has become a smart instrument of protests and communication. Digital revolution is igniting political and social revolutions through social media using leading edge communication and data sharing gadgets. Social media has been found supporting civic-state engagement [CSE] and helpful in reducing political apathy [PA] particularly in the developing states like Pakistan. The events of last decade in the ‘Middle East have verified the powers of SM in political activism and breaking the ice of PA. This study explores the same theory of relationships among the academicians of higher education in Khyber Pakhtunkhwa, Pakistan. The results confirm the hypotheses by giving significant statistics regarding both positive and negative relations of SM with CSE and PA respectively

Spate Irrigation: Impact of Climate Change with Specific Reference to Pakistan

Spate irrigation is a unique system of agriculture practiced in the piedmont plains by harvesting of floods received after rainfall in the mountains. This system is practiced in different parts of the world; in Pakistan, it is extensive in the western belt. The system is based on water distribution from head to tail. There are laws for distribution of water, but due to the magnitude of flood, it sometimes retains in the upstream and sometimes finds its way to the river. Agriculture practiced in this system depends on floods, which brings sedimentation, useful in replenishing soil fertility. Soil has the ability to hold moisture for long. The changing climatic pattern has greatly influenced the system both under droughts and floods. Livelihood of the spate farmers depends on agricultural crops and livestock. In either case of the extreme climate, they have to cope with limited options. Changing climatic pattern is responsible for extending the climatic seasons and enhancing the irrationality of floods. Construction of huge dam on the torrential watershed is a great project executed by the government for large floods, overcomes energy crisis, and has potential to irrigate land through canal. This chapter is a brief comprehension of spate irrigation under changing climate with special focus on Pakistan

Synchronization and antisynchronization protocol design of chaotic nonlinear gyros: an adaptive integral sliding mode approach

A novel control protocol design, via integral sliding mode control with parameter update laws, for synchronization and desynchronization of a chaotic nonlinear gyro with unknown parameters is the focus of this work. The error dynamics of the actual system are substructured into nominal and uncertain parts to employ adaptive integral sliding mode (AISM) control. The uncertain parameters are estimated via devised adaptive laws. Then the disagreement dynamics are guided to origin via AISM control. The stabilizing controller is also designed in terms of nominal control along with a compensating component. The control and the parameter update laws are constructed to ensure the strictly negative derivative of a Lyapunov function. Graphical results related to synchronization, desynchronization, and chaos suppression are displayed to demonstrate the potential of the proposed control

An integral sliding mode-based robust consensus control protocol design for electro-mechanical systems

This paper proposes a consensus tracking control for a class of second-order multi-agent nonlinear systems and generalizes the concept of integral sliding mode for networked systems. This design relies upon an integral manifold which is defined as a function of the consensus error variables. The designed integral manifold helps in the establishment of sliding mode without reaching phase. Consequently, the robustness against uncertainties is guaranteed from the very start. The continuous control components, of the control laws, governs the dynamics of the nonlinear system in sliding mode and the discontinuous terms handle the disturbances. The stability analysis is given to show the sliding mode establishment and an example is considered to demonstrate the benefits of the proposed strategy

A comparative experimental study of robust sliding mode control strategies for underactuated systems

This paper presents a comprehensive comparative study for the tracking control of a class of underactuated nonlinear uncertain systems. A given nonlinear model of the underactuated system is, at first stage, transformed into an input output form and the driving applied control input of the transformed system is then designed via four sliding mode control strategies, i.e., conventional first-order sliding mode control (SMC), second-order SMC, fast terminal SMC, and integral SMC. At the second stage, a ball and beam system is considered and the aforementioned four control design strategies are experimentally implemented. A comprehensive comparative study of the simulation and experimental results is then conducted, which take into account the tracking performance, i.e., settling time, overshoots, robustness enhancement, chattering reduction, sliding mode convergences, and control effort

Linear model identification of beetle-mimicking flapping wing micro-air vehicle in hovering flight

This paper presents a linear time invariant model identification for beetle mimicking flapping wing micro air vehicle (FWMAV) in hovering mode. The identification is facilitated by assuming the wings of the beetle rectangular in shape and the body is considered cylindrical. The main thrust is provided by flapping the wings of the FWMAV whereas the trailing-edges-change mechanism was kept off. The measurable aerodynamic forces and moment’s measured data are utilized in the states' reconstruction. The state reconstruction was carried out via the discrete time integration of linear and angular acceleration. Having reconstructed the states, the standard least mean square estimation (LMSE) based estimation approach is used to estimate the system’s stability and control derivatives. The results of the estimation are validated with the experimental data, and show the success of the estimation approach

Neural network-based adaptive global sliding mode MPPT controller design for stand-alone photovoltaic systems

The increasing energy demand and the target to reduce environmental pollution make it essential to use efficient and environment-friendly renewable energy systems. One of these systems is the Photovoltaic (PV) system which generates energy subject to variation in environmental conditions such as temperature and solar radiations. In the presence of these variations, it is necessary to extract the maximum power via the maximum power point tracking (MPPT) controller. This paper presents a nonlinear generalized global sliding mode controller (GGSMC) to harvest maximum power from a PV array using a DC-DC buck-boost converter. A feed-forward neural network (FFNN) is used to provide a reference voltage. A GGSMC is designed to track the FFNN generated reference subject to varying temperature and sunlight. The proposed control strategy, along with a modified sliding mode control, eliminates the reaching phase so that the sliding mode exists throughout the time. The system response observes no chattering and harmonic distortions. Finally, the simulation results using MATLAB/Simulink environment demonstrate the effectiveness, accuracy, and rapid tracking of the proposed control strategy. The results are compared with standard results of the nonlinear backstepping controller under abrupt changes in environmental conditions for further validation

Review of sliding mode control application in autonomous underwater vehicles

973-984This paper presents a review of sliding mode control for autonomous underwater vehicles (AUVs). The AUVs are used under water operating in the presence of uncertainties (due to hydrodynamics coefficients) and external disturbances (due to water currents, waves, etc.). Sliding mode controller is one of the nonlinear robust controllers which is robust towards uncertainties, parameter variations and external disturbances. The evolution of sliding mode control in motion control studies of autonomous underwater vehicles is summarized throughout for the last three decades. The performance of the controller is examined based on the chattering reduction, accuracy (steady state error reduction), and robustness against perturbation. The review on sliding mode control for AUVs provides insights for readers to design new techniques and algorithms, to enhance the existing family of sliding mode control strategies into a new one or to merge and re-supervise the control techniques with other control strategies, in which, the aim is to obtain good controller design for AUVs in terms of great performance, stability and robustness

Nonlinear robust integral sliding super-twisting sliding mode control application in autonomous underwater glider

1016-1027The design of a robust controller is a challenging task due to nonlinear behaviour of the glider and surround environment. This paper presents design and simulation of nonlinear robust integral super-twisting sliding mode control for controlling the longitudinal plane of an autonomous underwater glider (AUG). The controller is designed for trajectory tracking problem in existence of external disturbance and parameter variations for pitching angle and net buoyancy of the longitudinal plane of an AUG. The algorithm is designed based on integral sliding mode control and super-twisting sliding mode control. The performance of the proposed controller is compared to original integral sliding mode and original super-twisting algorithm. The simulation results have shown that the proposed controller demonstrates satisfactory performance and also reduces the chattering effect and control effort