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Superiority of Prostration as a Protection from Lightning Strike

Problem statement: Because of the significant fatalities due to lightning strikes in open fields, exploration has been made to find the human body’s most comfortable posture having the lowest length, width and height and the least ground touch in any terrain indoor and outdoor for the safest shelter from lightning strikes that neutralize an enormous amount of positive and negative charges. Approach: Risks of direct lightning strike and of side flash and ground current due to a lightning hit at a nearby place have been discussed along with an estimation of interlimb current for standing, sitting, lying flat and prostrated positions using the fundamental laws of electricity in physics. Results: It is found that prostration in which the body is comfortably squeezed within a length of one meter with the forehead-nose tip, the palms, the knees and the toes grounded, making a maximum body height about 35 cm, offers the least chance of a lightning strike, side flash hit and interlimb current flows, concluding the best shelter against lighting hit. Conclusion/Recommendation: Prostration is superior to all other postures of sitting and lying to lower our body weight in order to avoid dangers of lightning. During lightning, outdoor people who are not in closed safe transportations, or not in otherwise better shelters are recommended to use this posture of the body as a safe protection from lightning strikes. Considering the fatalities caused by lightning, families and communities should hold lighting drills before the advent of the lightning season.

Absolute Flux Comparison of Magnetospheric Particles

Problem statement: The calculation of magnetospheric particle flux by dividing the particle count rate by the instrument geometric factor does not take into account the anisotropic pitch angle distribution function. A comparison of particle fluxes measured by different instruments fail to lead to the right comparison. To circumvent the omission of anisotropy of the pitch angle distribution and to make the correct comparison of particle fluxes, the instrument response function to different pitch angles within the sampling range of the instrument has been incorporated into the count rates over a certain readout time. Conclusion/Recommendations: A quantity in absolute comparison of magnetospheric particle flux has been found. The newly defined quantity of different observations does lead to the correct comparison for studying temporal variations. Investigators interested to study temporal features of magnetospheric particles over epochs may find the response functions for different instruments flown at different epochs useful for their study.

Identification of Defects in Composite Materials Using an Improved Wavelet Analysis Algorithm

Problem statement: The present work carries on the use of a method based on the wavelet transform to detect internal flaws of composite materials. The objective of this work consists in working out a data processing sequence of an ultrasonic signal identifying nearly flaws in composite laminate materials and estimating their position. Approach: The use of a numerical signal processing technique, based on the Fast Wavelet Transforms was applied. Results: The method was implanted and optimized for detection and classification of delamination and porosity flaws in manufactured materials. Since the information about the signal requires a large amount of computation time and resources, a technique was used to reduce the dimensions of the sampling signals. In Non-destructive evaluation of stratified composite materials, the identification of some defect features requires more recent and advanced methods than classical techniques. Notably, in thin composite materials, the reflected NDE ultrasonic signals were overlapping. As a result, the flaws evaluation was becoming unfeasible. Many works dedicated to advanced signal processing based on time-frequency analysis had been widely used in Non-Destructive Evaluation (NDE) applications. To evaluate the nearly flaw detection of delamination and porosity enclosed in composite multilayer plate, the wavelet analysis was applied to ultrasound waveforms acquired by immersion pulse-echo technique. Conclusion: The obtained results offer some defect features relating their nature and position. The applied wavelet analysis provided excellent results for the investigated materials containing artificial delamination and porosity flaws.

The Concept of Event-Driven Time

The most fascinating feature of time is that there is no time at all. This study introduces the concept of event-driven time. Time is considered a count of changes or events that set up a local �clock� in each system. With such an approach, every system runs its own local time. Time does not exist without changes in the system. As two systems interact, they generate a sequence of interaction events that are being added to the internal pool of events in each system. Any observation is made with the local time of the observer system and this fact changes the observer�s local time by adding observation events to the observer�s time count. Local time in any finite and closed system is finite and obeys the saturation principle due to limitations of the event counting capacity of the system. Traditional continuous time is a convenient approximation for the enormous number of events occurring in our world that set up our local �clock�. The event-based approach does not conflict with modern physics but proposes a new view of the fundamental notion of time and brings us one step closer to understanding the world in which we live. The greatest mystery of the notion of time is that there is no time at all

Plasma Beams Free Vibration Ivestigation using the Boubaker Polynomials Expansion Scheme

Problem statement: In the present study, plasma beams free vibration frequencies alteration has been investigated through an original protocol. Approach: The Boubaker Polynomials Expansion scheme BPES has been performed for deducing and ranging the dimensionless frequencies of the beam vibrations. Results: Natural frequencies of the plasma beam have been estimated for given parameters values. Conclusion: Yielded results have been compared and discussed. It was found that a good agreement as the values determined with experimental results determined by previous researchers.

Implementation of an Improved Data Encryption Algorithm in a Web Based Learning System

Problem statement: This study proffered solution to some identified data insecurity problems in software development by the use of Web-based learning system as a test bed and development of an hybrid crypto-biometric security system. Approach: A variant of data encryption algorithm tagged (XOR-RSA algorithm) is developed in order to encrypt the messages being sent between the learner and the facilitator. Results: A comparative analysis of performance of this algorithm was carried out using cryptographic algorithm metrics in order to establish its stronger performance above the existing algorithms. The result shows that the improved algorithm (XOR-RSA) performed better than prominent data encryption algorithms in the likes of RSA, SKIPJACK, DES1 and 3DES. Conclusion/Recommendations: This was eventually implemented in a web based learning system. The work provides a prototype for the development of secured Web-based learning infrastructure and its contextual framework, which foster indigenization of electronic learning technology which will adequately address the related challenges in the phenomenon of system security in terms of confidentiality and integrity of the system.

Variable Separation and Boubaker Polynomial Expansion Scheme for Solving the Neutron Transport Equation

Problem statement: In this study, we present general analytical solutions to the Neutron Boltzmann Transport Equation NBTE using a polynomial expansion scheme. Approach: Some simple assumptions have been introduced in the main system thanks to the Boubaker Polynomial Expansion Scheme (BPES) in order to make the general analytical procedure simple and adaptable for solving similar real life problems. Results: Finding particular solution to the Neutron equation by making use of boundary conditions and initial conditions may be too much for the present study and reduce the generality of the solutions. Conclusion: The proposed analytical solution of the neutron transport equation has been positively compared to some recently publish results. I should present a relevant supply to studies on reactor modeling.

Electronegativity, Interaction Parameter and Electronicpolarizability for Bisumth Borate Metal Glasses

Problem statement: In the present work, we applied the concept of the optical electronegativity to predict basic properties of some ternary oxide glasses. Recently Optical electronegativity of many binary oxide glasses has been evaluated on the basis of two different parameters, the linear refractive index and the energy gap, which have demonstrated remarkable correlation. Approach: In this study, the refractive indexhas beendetermined through the optical electronegativity and obtain a perfect linear correlation between the calculated refractive index and the estimated values using the dielectric constant value of the prepared samples. Results: The average electronic oxide polarizability and the interaction parameter of our ternary oxide glasses have been estimated on the basis of the average optical electronegativity. Conclusion: The estimated values are in good agreement with the available experimental data. The present research is an improvement of the optical electronegativity determination.

New approach between the Optical Basicity and the Dielectric Constant through the Molar Polarizability for Some Binary Glasses

Problem statement: In the present study, a new correlation between the optical basiciry which describes the electronic charge clouds around the oxide glass and the dielectric constant has been proposed through the molar polarizability of the binary oxide glasses. Approach: Two experimental forms have been suggested relating the optical basicity and the molar electronic polarizability. Hence, the dielectric constant and the optical basicity for some binary glass systems can be deduced. Results: The molar polarizability and the dielectric constant of these glasses exhibit a linear relation as represented with the optical basicity. We have applied the proposed relation on the binary glasses. Conclusion: It was found that a good agreement as the values determined with experimental results determined by previous researchers.

On the Closed Form Solutions of Linear and Nonlinear Cauchy Reaction-Diffusion Equations Using the Hybrid of Fourier Transform and Variational Iteration Method

Problem statement: In the present study, a hybrid of Fourier transform and Variational Iteration Method (FTVIM) is developed for solving the non-homogeneous linear and nonlinear partial differential equations of Cauchy reaction-diffusion problem. Approach: The closed form solutions obtained from the series solution of recursive sequences is valid for the entire range of problem domain. Results and Conclusion: Moreover, the very rapid convergence towards the exact solutions using the new method, FTVIM, indicates that the amount of computational work is much less than the computational work required for both the previous VIMs and the modified VIMs.