VIBRATION ENERGY HARVESTING TECHNIQUE: A COMPREHENSIVE REVIEW

In order to minimize the requirement of external power source and maintenance for electric devices such as wireless sensor networks, the energy harvesting technique based on vibrations has been a dynamic field of studying interest over past years. Researchers have concentrated on developing efficient energy harvesters by adopting new materials and optimizing the harvesting devices. One important limitation of existing energy harvesting techniques is that the power output performance is seriously subject to the resonant frequencies of ambient vibrations, which are often random and broadband. This paper reviews important vibration-to-electricity conversion mechanisms, including theory, modelling methods and the realizations of the piezoelectric, electromagnetic and electrostatic approaches. Different types of energy harvesters that have been designed with nonlinear characteristics are also reviewed. As one of important factors to estimate the power output performance, the energy conversion efficiency of different conversion mechanisms is also summarized. Finally, the challenging issues based on the existing methods and future requirement of energy harvesting are also discussed.

SOLAR PANEL DUST MONITORING SYSTEM

Solar energy has been one of the most explored sources of renewable due to its economical source of energy. However, the main barrier for solar energy generation is the present of dust particles on the panel surface that decreases its performance. Hence, persistent monitoring on dust accumulation is of importance to guarantee the optimum power is achieved. Thus, this research aims to develop the real-time dust monitoring system of the solar panel. A dust sensor with IoT will be developed for this purpose. The reading of dust accumulation will be recorded and is accessible online through smartphones or desktop.

DEVELOPING GUIDELINES FOR ENVIRONMENTAL IMPACT ASSESSMENT OF KASHMIR UNDERPASS PROJECT IN FAISALABAD

Road development projects are important as they provide economical, political and social benefits but delays can occur. EIA is conducted for every project as required by the Environmental Protection Act of 1997 and the Environmental Policy of Pakistan for the purpose of ensuring mitigation of environmental impacts due to project activities. The Kashmir Underpass project in Faisalabad is assigned to FDA, for the purpose of satisfying growing need of traffic load due to population increase in surrounding areas in newly developed societies. This research examines the different factors of project affecting the environment. Questionnaire approach was utilized to gain insights of environmental impacts due to the project. Results showed that 93% of respondents didn’t knew about EIA and why it is necessary. Respondents were facing impacts from dust particles, noise, traffic, business loss etc. These impacts were analyzed and guidelines were developed for EIA of Kashmir Underpass Project.

ANALYSIS OF EARTH FILL HYDRAULIC DAM WITH VARYING CREST LENGTH AND PERMEABILITY TO DEVELOP CORRELATIONS

In this paper, an earthen dam is analysed using different soil layers having different soil properties and dimensions. Normally a slope fail when the shear strength reduces from the minimum required value which keeps it stable. Internal erosion is the main cause which causes a dam to fail and it is mainly due seepage with time. A detail analysis of a predefined dam slope is performed in different layers to check the seepage variation as well as the factor of safety. Different soil layers and properties were used such that it is investigated from a fail condition to a complete stable condition. Limit equilibrium and finite element approaches are used. Correlations for factor of safety between these two approaches are also developed. These correlations and results could be used as guidelines in any dam or slope safety calculation.

A STUDY OF PSEUDO SPECTRAL GALERKIN METHOD FOR SOLVING DIFFERENTIAL EQUATIONS

Differential equations have a remarkable potential to exhibit real life phenomenon. Many methods have been developed to solve these differential equations, though only a few stands with time. This paper presents a comparison of Pseudo Spectral Galerkin Method for solving ordinary differential equations with many other global methods. Results shows the high accuracy and rapid convergence of said method. Graphical comparison and error tables have been provided for better understanding of results.

SEISMIC ANALYSIS OF A SOIL SLOPE TO DEVELOP CORRELATIONS FOR FACTOR OF SAFETY CONSIDERING HORIZONTAL AND VERTICAL SEISMIC COEFFICIENTS

Seismic analysis of soil slopes is required to get safe value for slope design. Especially in earthquake zones. Normally a variation in factor of safety values is observed in normal analysis of a slope where seismic coefficients are kept zero as compare to seismic analysis where seismic coefficients are considered in the analysis. In this research, seismic horizontal coefficients are used to find the factors of safety. Correlations are developed between factor of safety values and seismic coefficients. The correlation can be used to find the factor of safety in any slope stability project for a homogenous slope. The outcome of this work are the correlations. These correlations can be used to find the factor of safety values considering horizontal seismic coefficient, vertical seismic coefficient and both.

RAINFALL TREND AND IT IMPACT IN KEFFI NASARAWA STATE

Rainfall is the vital ingredient and factor of soil nourishment on which crops are grown. The basic agricultural practices all over the world depend on rainfed cultivation for their sustainable development. This study focus on the rainfall trend between 2010 -2018 as it affects crop production in Keffi Nasarawa State, Nigeria. The time series analysis was conducted by using appropriate techniques of data collection and analysis. The linear integration model, quadratic trend model, growth curve model and regression analysis was applied to show the correlation between the rainfall and crop production in the study area. It was discovered that the period of rainy months have high correction and significantly fitted the model which indication high crop yields per harvest.

IMPROVEMENT OF THE HYDRAULIC JUMP FEATURES USING INCOMPLETE CIRCULAR PILES

The roughness elements are efficient tools to control the features of the hydraulic jump in the rectangular stilling basins. The present study suggests the use of modified elements to control the features of the free jump. The proposed tool is an incomplete circular pile. The use of piles in a one row with the different setup has been investigated. The measurements showed that the case of piles with the comparative summation areas A/∆=6.72 and the comparative distances between piles X/H1 =0.0 reduced the comparative height and length of the free jump by 11% and 24.6%, respectively. The paper detected the necessary helpful statistical formulas for the phenomenon.

GAS LIFT OPTIMIZATION OF A MATURE WELL IN NIGER DELTA, NIGERIA USING INCOMPLETE DATASET: A CASE STUDY

Well DEF, a well located in Niger Delta region of Nigeria was shut down for 7 years. On gearing towards re-starting production, different options such as installation of gas lift mechanism, servicing and installation of packers and valves were evaluated for possibility of increasing well fluid productivity. Hence, this research was focused on optimizing well fluid productivity using PROSPER through installation of continuous gas lift mechanism on an existing well using incomplete dataset; in addition, the work evaluated effect of gas injection rates, wellhead pressure, water cut and gas gravity on efficiency of the artificial lift mechanism for improved well fluid production. Results of the study showed that optimum gas injection rate of 0.6122 MMscf/day produced well fluid production of 264.28 STB/day which is lower than pristine production rate (266 STB/day) of the well. Also, increment in wellhead pressure resulted in decrease in well production, increase in water cut facilitated reduction in well fluid productivity while gas gravity is inversely proportional to well fluid productivity. Based on results obtained, authors concluded that Well DEF does not require gaslift mechanism hence, valves and parkers need to be re-serviced and re-installed for sustained well fluid.

SOIL STABILIZATION AND IMPROVEMENT OF MARINE CLAYS USING CEMENT AND LIME IN A MARSHLAND

This study assesses the stabilization of marine clay soil using cement and lime to improve on the subgrade material. The tests conducted include: the natural moisture content, specific gravity, sieve analysis, Atterberg limit, compaction and California Bearing Ratio (CBR). The types of stabilization used were mechanical and chemical. The results obtained were classified using AASHTO classification system and based on the results the soil corresponds to group A-6 soils. The highest CBR values of 33.24% and 424.35% were obtained at 20% cement content for unsoaked and soaked and for lime the highest CBR values were 5.07 and 10.46 for 11% lime content for both unsoaked and unsoaked. Based on the results obtained, the addition of cement and lime to clay soil in the presence of water improved the CBR values for soft clay stabilization for highway construction with low traffic volume. It is therefore concluded that the addition of cement and lime to clay soil improved the bearing capacity and the maximum dry density of the clay soil. Further research should be carried out to examine the effects of industrial by-products on effective clay soil stabilization.