Novel nonimaging solar concentrator for portable solar systems for developing countries

Portable solar chargers have been gaining popularity as a new technology to help increase electrification in rural areas in developing countries. It is a fast developing industry aiming to produce a low-cost solution for the application of off-grid solar lighting and charging of small devices to be used by the poorest and most vulnerable of society. Solar concentrators are proposed as an add-on to help further reduce costs, to increase light-output hours and to reduce charging time. So far, no suitable concentrator designs have been proposed. This paper presents a novel concept for the design of a static nonimaging concentrator, suitable for portable solar systems for developing countries. The novel concentrator design is compared with existing concentrators and its suitability for portable solar chargers, as well as its potential for further improvement, are highlighted

Modeling and simulation of heterojunction solar cell; determination of optimal values.

A heterojunction solar cell of ZnSe/ZnO/CIGS/Si structure has been simulated in order to determine the optimal values. The performed modeling and Simulation is used to get an idea and identify the optimal values that can be use in the manufacturing process, and the values obtained in this simulation presented an electrical parameters using Solar Cell Capacitance Simulator (SCAPS). In this study, the influence of absorber or wafer thickness and doping concentration were varied on the solar cell device and the following optimal values were obtained; Current density (Jsc)=35.0833SmA/cm2, Open circuit voltage (Voc)=0.S339V, Fill Factor (FF) =S5.45%, and an efficiency (η)=25%. The range of doping concentration (lx1012 to lx1020 cm−3). These variations lead to the achievement of 25% efficiency of the heterojunction solar cell and the optimal values shows a promising performance that the manufacturers can adopt

Polymer nanocomposites and related legal issues: an overview.

Manipulation of engineered nanomaterials (ENMs) to develop different consumer and industrial products are the preferred choice in modern day industrial production due to their unprecedented, but diversified promises and prospects. The researchers claimed in 2006 that the NMs were in a stage where plastic was in the 1960s. This analogy was made to indicate the potential wide use of the NMs in consumer and industrial products. Burgeoning research has been carried out in almost every corner of the world to explore and exploit the prospects of ENMs. Application of nanoparticles (NPs) into polymer matrix materials have also been tested, and dramatic changes in the mechanical, thermal, electrical, and diffusion properties to the properties of the host polymers were observed. The polymer nanocomposites (PNCs) are undoubtedly very prospective and it can be anticipated that PNCs will widely be used in the automotive industry to replace the metal accessories and to reduce CO2 emissions. However, in order to do so, it is crucial that the manufacturers handle different socio-legal and regulatory issues around the ENMs and PNCs carefully. This record only contains an introduction to the chapter, the full chapter is available from: https://doi.org/10.1016/B978-0-12-811033-1.00026-

Eye-tracking assistive technologies for individuals with amyotrophic lateral sclerosis

Amyotrophic lateral sclerosis, also known as ALS, is a progressive nervous system disorder that affects nerve cells in the brain and spinal cord, resulting in the loss of muscle control. For individuals with ALS, where mobility is limited to the movement of the eyes, the use of eye-tracking-based applications can be applied to achieve some basic tasks with certain digital interfaces. This paper presents a review of existing eye-tracking software and hardware through which eye-tracking their application is sketched as an assistive technology to cope with ALS. Eye-tracking also provides a suitable alternative as control of game elements. Furthermore, artificial intelligence has been utilized to improve eye-tracking technology with significant improvement in calibration and accuracy. Gaps in literature are highlighted in the study to offer a direction for future research

Using Illustrations to Make Decisions on the Most Appropriate Qualitative Research Methodology: The Industry 4.0 Scenario

Industry 4.0 is viewed as a complex scenario. This complex scenario could be interpreted using illustrations such as sketches or drawings. Ideally, sketches and drawings are useful in illustrating complexity and multiple abstracts from observed social reality. The use of illustrations allows novice qualitative researchers to explore observed social reality in depth with less linear insight. However, few scholars mention the use of illustrations at the research planning stage because most sketches and drawings have been used as tools during data collection, merely to understand an interviewee's perspective. Therefore, this article aims to demonstrate the use of illustrations as a tool to facilitate the research process from problem identification to the selection of the qualitative research methodology. Five specific purposes of illustration that significantly contribute to the body of knowledge for effective decision making and are useful tools in delivering information are demonstrated in this article. Based on the illustrations demonstrated in this article, the most appropriate qualitative research methodology is the case study. Overall, the proposed use of illustrations can assist a novice qualitative researcher in determining the appropriate epistemological and ontological stances - as well as their methodology and method - more effectively

Modelling of electroluminescence in polymeric material using dimensional analysis method: effect of applied voltage and frequency.

Electroluminescence (EL) method has been used by several researchers to observe the behaviour of an aged polymeric material. EL is a phenomenon that occurs when the atoms of a material are being excited due to the application of and external high electrical stresses. The changes in the energy level of these excitation states can be used as an indicator for the initiation of electrical ageing. There are several factors that affect the behaviour of EL emission such as, among others, applied voltage, applied frequency, ageing of material and types of materials and gases used are discussed in this paper. A mathematical approach relating these factors and the intensity of EL is proposed through the aid of Dimensional Analysis method. A close relationship is obtained between experimental and simulation that suggests this mathematical approach can be utilized as a tool to predict electrical ageing of insulation material

A Study on the Correlation Between Hand Grip and Age Using Statistical and Machine Learning Analysis

Handgrip strength (HGS) is an easy-to-use instrument for monitoring people's health status. Numerous researchers in many countries have done a study on handgrip disease or demographic data. This study focused on classifying aged groups referring to handgrip value using machine learning. A total of fifty-four participants had involved in this study, ages ranging from 24 years to 57 years old. Digital Pinch Grip Analyzer had been used to measure the handgrip measurement three times to get more accurate results. The result is then recorded by Clinical Analysis Software (CAS) that is built into the analyzer. An independent t-test is used to investigate the significant factor for age group classification. The data were then classified using machine learning analysis which are Support Vector Machine (SVM), Random Forest (RF), and Naïve Bayes. The overall dataset shows that the Support Vector Machine is the most suitable classification technique with average accuracy between 5 groups of age is 98%, specificity of 0.79, the sensitivity of 0.9814 and 0.0185 of mean absolute error. SVM also give the lowest mean absolute error compared to RF and Naïve Bayes. This study is consistent with the previous work that there is a relationship between handgrip and age

A Study on the Correlation Between Hand Grip and Age Using Statistical and Machine Learning Analysis

Handgrip strength (HGS) is an easy-to-use instrument for monitoring people's health status. Numerous researchers in many countries have done a study on handgrip disease or demographic data. This study focused on classifying aged groups referring to handgrip value using machine learning. A total of fifty-four participants had involved in this study, ages ranging from 24 years to 57 years old. Digital Pinch Grip Analyzer had been used to measure the handgrip measurement three times to get more accurate results. The result is then recorded by Clinical Analysis Software (CAS) that is built into the analyzer. An independent t-test is used to investigate the significant factor for age group classification. The data were then classified using machine learning analysis which are Support Vector Machine (SVM), Random Forest (RF), and Naïve Bayes. The overall dataset shows that the Support Vector Machine is the most suitable classification technique with average accuracy between 5 groups of age is 98%, specificity of 0.79, the sensitivity of 0.9814 and 0.0185 of mean absolute error. SVM also give the lowest mean absolute error compared to RF and Naïve Bayes. This study is consistent with the previous work that there is a relationship between handgrip and age

An experimental study on the effect of methane potent biogas mixture on gas permeation mechanism.

This study focuses on the use of composite alumina membranes for the separation of carbon dioxide from methane. The technique can be applied to pre, post and oxycombustion operations in industry and would be particularly useful in mitigating the effect of greenhouse gases in our world today. The porous tubular ceramic supports used in this study were tailor made by Ceramiques Techniques et Industrielles (CTI SA) in France consisting of an alumina support and separation layer of pore sizes ranging from 15 – 6000nm. The membrane layers are fixed on the support, starting with very coarse (intermediate) layers then more layers with decreasing pore sizes are added until the designated pore sizes are reached. For example, to achieve a membrane with the pore size of 6000nm, the support will have one layer (1) of a macroporous membrane, while a membrane with pore size of 200nm will have the support plus layer (1) and layer (2). Again, to achieve a membrane with mesoporous size of 15 nm, we will have the support plus layers (1 + 2 + 3). The layers are made from different materials such as aluminium oxide (Al2O3), titanium oxide (TiO2), zirconium oxide (ZrO2), silicon dioxide (SiO2), silicon carbide (SiC). Materials are carefully selected so that they are thermally compatible with the support to prevent delamination or crack formation at elevated temperatures

Experimental evaluation of a solar window incorporating rotationally asymmetrical compound parabolic concentrators (RACPC).

Building integrated photovoltaic (BIPV) systems have been proposed to make solar photovoltaic systems more attractive. These systems are not only capable of generating electricity, but can also contribute to minimise energy consumption in buildings by providing natural illumination, space and water heating, ventilation and shading. Despite these advantages, one of the issues that still prevents the widespread adoption of BIPV systems is their high capital cost. This paper discusses a novel type of non-imaging optical concentrator that can be used to reduce the capital cost of a BIPV system. This new concentrator, known as rotationally asymmetrical compound parabolic concentrator (RACPC), has a flat entrance aperture that facilitates integration within a double-glazing window and reduces fabrication costs. The RACPC, which has a geometrical concentration of 3.66x, also offers other advantages over conventional solar concentrators: suitability for fenestration, ease of integration with square PV cells, and passive tracking. Several experiments were carried out on a double-glazing solar window incorporating an array of 4x3 concentrator-PV cells. The experiments were carried out indoors under standard test conditions. The results show that the RACPC-PV window effectively increases the short-circuit current by a factor of over 3 at normal incidence when compared with a non-concentrated solar window. The solar window also shows an increase in maximum power generation by a factor of nearly 3