Theoretical study of the effect of fibre orientations and porosity on heat conductivity of reinforced polymer composites

In recent years, there has been an increasing demand for engineering materials which not only possess good mechanical and thermal properties but are also cheap and environmentally friendly. Composites are unique engineering materials which can be tailor made from a large variety of materials to suit specific applications. Composites primarily consist of a polymer resin matrix in which other material is incorporated in discrete units for reinforcing. The reinforcing materials can be in the form of fibres or flakes orientated in various ways to impart maximum performance. Natural fibres such as sisal, kenaf, bagasse, hemp etc. have been studied as reinforcing material for conventional polymer resins. Such composites are often termed green composites and they have unique mechanical properties when compared to conventional composites. They are also available at a cheap price and weigh a lot less. In addition, they can also offer unique thermal and acoustic insulation properties. Due to these attractive features they are used in the automotive, aerospace, textile and construction industries. A particularly important feature which determines the properties of natural fibre composites and their porosity. From an industrial and academic point of view, there is a need to study the heat conductivity of newly developed composites. This is influenced by the porosity of the composite. This project, investigated the effect of porosity and their orientation on the heat conductivity of polymer composites. Experimental and theoretical studies were conducted on mainly sisal-glass fibre polymer composites. Different volume of fibre fractions were tested in this study. It was expected that the presence of the fibres would dramatically improve the heat conductivity properties of the materials because the sisal fibres have internal porosity. The results of this work are expect to contribute to academic and industrial knowledge about the thermal performance of fibre composites. The data will be published in a professional journal. This knowledge will contribute to the manufacturing of newly developed materials for industrial applications

Numerical analysis of the thermomechanical behaviour of an integrally water-heated tool for composite manufacturing

Integrally water-heated tooling is one of the technologies available for ‘out-of-autoclave’ processing of advanced thermoset polymer composites. Temperature variation and temperature cycling, during heating and cooling, affect the properties of tool material and may produce undesirable thermal effects that degrade the tool durability and performance, especially when the tool construction involves various materials. Hence, in the current study, the performance and the thermomechanical behaviour of an integrally water-heated tool have been investigated using finite element analysis method. The intended tool, in the current study, consists different materials of composite and metals and is designed to heat up to 90℃. Linear mechanical properties, coefficient of thermal expansions and transient heating curve of each tool part are determined experimentally and set during the numerical analysis of tool structure to calculate the static thermal load effects of deformation, stress and strain. Comparing the numerical thermal effects with the ultimate stresses and strains of the tool, materials concluded that no failure occurs with regard to static thermal loads. However, the calculated stresses are as much as the lowest magnitude of safety relates to the tool mould part made of Alepoxy. </jats:p

A Secure Image Steganography Using Shark Smell Optimization and Edge Detection Technique

The stegangraphic system supply premium secrecy and ability of conserving the mystery information from gaining stalked or cracked. The suggested method consists of three phases which are edge detection, embedding and extraction. This paper concentrated on three basic and significant parts which are payload, quality, and security also introduces a new steganography method by using edge detection method and shark smell optimization to effectively hide data with in images. Firstly, to promote the hiding ability and to realize altitude standard of secrecy the mystery message is separated into four parts and the cover image is masked and also divided into four sections, then the edge detection algorithm and shark smell optimization is performed on each section respectively. Edge prospectors were utilized to produce edge pixels in every section to hide mystery message and attain the best payload. To increase security, the shark smell optimization is used to select the best pixels among edge pixels based on its nature in motion, then reflect these pixels above original carrier media. Finally the mystery message bits are hidden in the selected edge pixels by using lest significant bit technique. The experimental outcomes appreciated utilizing several image fitness appreciation fashion, it displays best hiding ability, achieve higher image quality with least standard of deformation and provide altitude standard of secrecy, also the results shows that the suggested method exceeds previous approaches in idioms of the PSNSR, MSE also demonstrate that the mystery information cannot be retrieved of the stego image without realizing the algorithms and the values of parameters that are used in hidden proces

Anisotropic diffusion of water molecules in hydroxyapatite nanopores

Funded by EPSRC Grant EP/K000128/1

Reducing the environmental impact of surgery on a global scale: systematic review and co-prioritization with healthcare workers in 132 countries

Abstract Background Healthcare cannot achieve net-zero carbon without addressing operating theatres. The aim of this study was to prioritize feasible interventions to reduce the environmental impact of operating theatres. Methods This study adopted a four-phase Delphi consensus co-prioritization methodology. In phase 1, a systematic review of published interventions and global consultation of perioperative healthcare professionals were used to longlist interventions. In phase 2, iterative thematic analysis consolidated comparable interventions into a shortlist. In phase 3, the shortlist was co-prioritized based on patient and clinician views on acceptability, feasibility, and safety. In phase 4, ranked lists of interventions were presented by their relevance to high-income countries and low–middle-income countries. Results In phase 1, 43 interventions were identified, which had low uptake in practice according to 3042 professionals globally. In phase 2, a shortlist of 15 intervention domains was generated. In phase 3, interventions were deemed acceptable for more than 90 per cent of patients except for reducing general anaesthesia (84 per cent) and re-sterilization of ‘single-use’ consumables (86 per cent). In phase 4, the top three shortlisted interventions for high-income countries were: introducing recycling; reducing use of anaesthetic gases; and appropriate clinical waste processing. In phase 4, the top three shortlisted interventions for low–middle-income countries were: introducing reusable surgical devices; reducing use of consumables; and reducing the use of general anaesthesia. Conclusion This is a step toward environmentally sustainable operating environments with actionable interventions applicable to both high– and low–middle–income countries

Smart Cities and The UAVs Applications. A Review Of The Ongoing Research in The UAVs Unit

Nowadays, drones are one of the most important and valuable sources for acquiring aerial imagery and data related to inspection, monitoring, mapping, smart city organization, disaster monitoring and prevention, and 3D modeling. Drones are a low-cost alternative to aerial and space photography because they provide users with images with high spatial resolution down to centimeters. These images enable the production of accurate 3D models such as Digital Surface and Terrain Models (DTM/DSM), contour lines, vector information, etc. This research provides a brief overview of the studies conducted in the Unmanned Aircraft Unit - Remote Sensing Center - University of Mosul. The programs, sequence of operations, and treatments that were followed on the drone images taken by these aircraft were reviewed to prepare them for use in remote sensing and aerial survey operations. This flows towards the use of this technology in the development of smart cities. Specialized GIS software was also used to analyze and process the aerial images that were taken using the DJI Phantom 4 aircraft to study several areas in the city of Mosul, where several sorties were conducted at different periods and times of time

Green biopolymer and plasticizer for solid electrolyte preparation: FTIR, electrochemical properties and EDLC characteristics

In this study a green electrolyte was developed by incorporating methylcellulose (MC) polymer with potassium thiocyanate as ion provider and plasticized with glycerol to enhance salt dissociation. The purpose of glycerol addition was to improve DC conductivity and to enhance the performance of an electric double-layer capacitor (EDLC) device. The electrochemical and structural characteristics of the green electrolyte were examined. The broadening of the FTIR bands and a decrease in intensity indicated the interaction between the electrolyte components. The suitability of the electrolyte films for device applications was confirmed by measuring ionic conductivity using electrochemical impedance spectroscopy (EIS) skills. A significant amount of charge was concentrated at the electrode–electrolyte interface because of the high dielectric constant of the electrolyte. The loss tangent (tan δ) and modulus (M“) spectra obtained from electrical impedance spectroscopy showed distinct peaks associated with ion relaxation processes. The results of the transference number measurement (TNM) experiment indicated that ions were more influential than electrons. The stability of the film under different voltage conditions was evaluated using the linear sweep voltammetry (LSV) method. The performance of the EDLC was determined through cyclic voltammetry (CV) and charge–discharge evaluations. The CV pattern of the device at low scan rates showed a non-Faradaic mode of charge storage with a nearly rectangular shape. The newly constructed EDLC exhibited an initial capacitance per unit mass of 79F/g, a utilization efficiency of 87%, a power density of 1950 W/kg, and an energy storage density of 12.1 Wh/kg