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This paper presents the optimum solar collector tilt angles that will result in maximum solar radiation on the surface of collectors for each climatic zone in Saudi Arabia. The study has been done on the hourly diffuse and daily global solar radiation values on a horizontal surface. The percentage increase in the value of solar radiation gain for both seasonal and monthly optimum tilts are determined with respect to the annual fixed tilt for the different climatic zones of Saudi Arabia. A correlation that determines the optimum tilt angle as a function of latitude and month is developed for the different climatic zones of kingdom of Saudi Arabia.

This paper comprises of portable grounding system for the safe operation of electrical system and to avoid the fatal accident related to electrical surges arises from fault current and lightning strokes. Grounding system is mainly affected by grounding resistance and nature of soil. During lightning strikes or short circuit surge arises grounding system should be capable of handling high current for short or prolong period. In conventional grounding system the material used are sand, salt and charcoal mixture. The disadvantages encountered in the use of conventional materials are dissipation in ground, high resistance and require deep digging of electrode. This paper investigates the electric field strength of proposed sample through FEA software. The tests are conducted to analyze the breakdown behavior of silica sand, china clay, bentonite and their mixture under alternating and direct current conditions. The electrical grounding system is made portable to provide low and acceptable resistance path for terrains where soil is not suitable for grounding system like forests, deserts and abnormal surfaces, eliminating the issue of deep digging of grounding electrodes.

The four-bar mechanism is a very useful mechanism that is part of all the machines. Four-bar mechanisms are used in various components of the automobiles, ranging from the simple windshield wiper mechanism to the sophisticated suspension system. This paper deals with the dynamic modeling and analysis of the 4-bar mechanisms that can help in the achievement of maximum accuracy in the output motion in the automobile applications. Both the kinematical and kinetic analyses are performed in this study. The dynamic modeling of the four-bar mechanism was performed in MATLAB and ADAMS software in order to accurately predict the motion of the output and coupler links for a corresponding motion of the input link.

Statistics show that almost 10% of the total road accidents are because of the rollover of heavy-duty tankers. The probability of rollover is higher in partially filled tankers than the filled tankers. The higher tendency of rollover accidents in partially filled tankers is because of the liquid sloshing inside the tankers. This rollover inside the tanker results in the dynamic instability of the tanker. The rollover stability is sensitive to the shape of the tanker, the properties of the fluid inside the tanker, the fill level of the tanker and the location of the baffles inside the tanker. The baffles and active rollover control system can be used to overcome the dynamic instability of the heavy-duty tankers. Active control system can limit the dynamic shifting of Center of Gravity (C.G). Baffles on the other hand found to be more effective in terms of minimizing the dynamic moments and forces on the tanker's wall. Different baffle configurations can be used to reduce the liquid sloshing effect. However, this research is mainly focus on determining the effect of different locations of horizontal baffles for different fill level of an elliptical tank. The effect of baffle location was analyzed numerically in terms of dynamic moments and forces. The numerical modeling was performed using the Volume of Fluid (VOF) method and the commercial CFD tool CFD-RC. The post analysis was done using custom computer codes to evaluate the resultant dynamic forces and moments.

The vehicle suspension system is one of the main design factors in the automobile industry that can exponentially increase the level of customers comport and satisfaction. Various design strategies can be used to get optimum values for the various parameters in the suspension system. In this paper, a passive vehicle suspension system was modeled, and the system was optimized using Genetic Algorithm (GA) optimization technique. The GA is based on natural evolution and is successfully applied to various real-world problems. The variance of the dynamic load resulting from the vibrating vehicle is taken as the performance measure (i.e., objective function) of the suspension system. During the application of GA, first appropriate mutation rate, crossover rate, and population size were evaluated which were used to calculate optimum values for the parameters in the suspension system. The optimum values for the suspension system correspond to minimum values of the settling time and maximum overshoot and thus helps in decreasing the effect of the dynamic loads by reducing the vehicle vibration.

Researchers have widely used statistical and machine learning techniques to construct prediction models in several domains such as prediction of software faults, spam detection, disease diagnosis, and financial fraud identification. The prediction of patients prone to lung cancer can help doctors in their decision making regarding their treatments. In this regard, this research paper attempts to evaluate the discriminative power of several predictors in the study to increase the efficiency of lung cancer detection through their symptoms. A number of classifiers including Support Vector Machine (SVM), C4.5 Decision tree, Multi-Layer Perceptron, Neural Network, and Naive Bayes (NB) are evaluated on a benchmark dataset obtained from UCI repository. The performance is also compared with well-known ensembles such as Random Forest and Majority Voting. Based on performance evaluations, it is observed that Gradient-boosted Tree outperformed all other individual as well as ensemble classifiers and achieved 90% accuracy.

Simulation driven designs are used for the efficient development of high precision devices such as parallel manipulators/platforms. Accurate prediction of these simulations depends upon the fact that how closely actual conditions are incorporated in the analysis. Stiffness is a key property for parallel platforms as it dictates the positional accuracy of the system. Overall stiffness of the platforms is not only driven by the stiffness of the links but also by contact stiffness of joints. Heavily loaded platforms present a special case as these are more prone to system failure if not designed properly. In this work, the stiffness behavior of 6-DOF platform’s top plate subjected to various boundary conditions at joints have been analyzed. Different boundary conditions i.e. volume at joints, surface at joints and line at joints, has been used to depict real joint behavior. The stiffness of platform is analyzed for each of these cases independently and comparison of simulation results for every condition is presented both for static as well as dynamic conditions. This comparison presents a useful outcome for better prediction of static stiffness behavior and dynamic response thus aiding in more accurate design of such applications.

In this study, dynamic analysis is conducted on a Floating Mooring Line-Driven Platform (FMDP) subjected to sea wave forces. The effect of changing mooring lines pattern is investigated to enhance the dynamic behavior of the FMDP. The analysis is demonstrated with six mooring lines FMDP. A new mooring lines pattern (6-3-3) is studied and compared with the (6-6) Stewart-Gough manipulator pattern. The dynamic behavior, cables tension, and platform stiffness are determined across FMDP effective area. The dynamic analysis of FMDP is improved using the new mooring lines pattern (6-3-3).

We investigate a plasmonic electro-optic modulator with an extinction ratio exceeding 1 dB/μm by engineering the optical mode to be in-plane with the graphene layer, and show how lowering the operating temperature enables steeper switching.

The parameter sensitivity is a major cause of AC drives to stop working optimally. This paper looks into fractional order controller for Interior Permanent Magnet motors. The interior permanent magnet motors have become more demanding in hybrid vehicles, for which the parameter (resistance, inductance, magnetization of permanent magnets) drift is a common cause of degradation of drive due to rise in ambient temperature. The fractional PI/PID controller, which has five degree of freedoms, compared to classical PI/PID which have three degree of freedoms. This paper presents the simulations of fractional order controller (PI) based on fractional order calculus, for robust speed control of the Interior permanent magnet motors. The fractional order controller is compared with the well-tuned PI controller. The analysis constitutes the big range of parameters drift of the motor, to compensate the range of actual drift in the parameters.

The voting system is set of rules which define how the desire of people may be express and how results may be achieved from it. For this purpose an electronic voting machine EVM is introduced in this paper which replaced conventional methods of voting i-e manual voting. Proposed machine in this paper is faster, efficient, and reliable and error free as compared to manual voting system which is slower, poses full day fatigue on people and chances of error are greater. Its main feature is its ease to operate. Voter polls a vote very easily and final results are displayed in no time by just pressing a result button, after the elections have been conducted.

In this paper, we study the problem of optimizing the error generated in the allocation of processing elements to tasks, based on real-time scheduling. The makespan of the tasks to be scheduled is the same, in the computational grid. Tasks to be assigned to processing elements are randomly generated and are mapped to processors. Scheduling is done, considering real-time environment and mapping is achieved via biased and unbiased mapping of tasks to processors. The heuristics are used with the simulated computational grid and the results are compared extensively against each other.

In deregulated power market, the variation of demand curves with the varying weather parameters is a probabilistic problem. The weather parameters, such as temperature, humidity, and precipitation affect the load requirements in non-autonomous wide area smart grid system. We modeled the relationships of the load with aforementioned weather parameters. Moreover, various correlation models, such as Pearson, Spearman, and Kendall are quantitatively analyzed for each independent weather data variables. Furthermore, simple linear regression and multi-linear regression techniques are applied for the statistical varying load model in the wide area smart grid system. The effect of each independent variable on the dependent variable (load) is critically observed using statistical tool R. The linear and non-linear varying patterns exhibited monitoring information for the load control and management of wide area smart grid system.

Smart grid is the future for the conventional power systems. In Pakistan, many energy projects are completed and some of them are under still in implementation phase. The aim of this paper is to highlight the prosperous developments in energy sector for the smart grid implementation. The basic objective that is targeted is to have sufficient energy production as compared to connected load at the distribution section. We provide a detail overview of the running projects, past projects, and future projects for the smart grid implementation in Pakistan. The first basic step towards smart system is to have sufficient generation than demand of the consumers. Our paper highlights the energy potential in Pakistan and various energy statistics, such as installed capacity.

Voltage and frequency is dynamically scaled to produce energy efficient multi-core network-on-chip (NoC). A detailed analysis of the techniques employed for this purpose are studied and based on the optimized performance the most effective ones are reported. We also highlight the most promising high performance and energy minimizing techniques.