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In-vivo experimental techniques to understand the biomechanical behavior of a restored tooth, under varying oral conditions, is very limited because of the invasive nature of the study and complex tooth geometry structure. Therefore, 3D-Finite element analyses are used to understand the behavior of a restored tooth under varying oral conditions. In this study, the distribution of maximum principal stress (MaxPS) and the location of MaxPS on a restored tooth using six different commercially available dental resin composites under the influence of thermal and thermomechanical stimuli are performed.An intact tooth was scanned using µ-CT and segmented to obtain separate geometric models of the tooth, including enamel and dentine. Then, a class II mesial-occlusal-distal (MOD) cavity was constructed for the tooth model. The restored tooth model was further meshed and imported to the commercial Finite Element (FE) software ANSYS. Thermal hot and cold stimuli at 50 °C and 2 °C, respectively, were applied on the occlusal and lingual surface of the tooth model with the tooth's ambient temperature set at 37 °C. A uniform loading of 400 N was applied on the occlusal surface of the tooth to imitate the masticatory forces during the cyclic thermal stimuli.The results of this study showed that the restorative materials with higher thermal conductivity showed a lower temperature gradient between the restoration and enamel, during the application of thermal stimuli, leading to a higher value of MaxPS on the restoration. Moreover, on applying thermal stimuli, the location of MaxPS at the restoration-enamel junction (REJ) changes based on the value of the coefficient of thermal expansion (CTE). The MaxPS distribution on the application of simultaneous thermal and mechanical stimuli was not only dependent on the elastic modulus of restorative materials but also their thermal properties such as the CTE and thermal conductivity. The weakest part of the restoration was at the REJ, as it experienced the peak stress level during the application of thermomechanical stimuli.The findings from this study suggest that restorative materials with lower values of elastic modulus, lower coefficient of thermal expansion and higher values of thermal conductivity result in lower stresses on the restoration. The outcomes from this study also suggest that the thermal and mechanical properties of a restorative material can have a considerable effect on the selection of restorative materials by dental clinicians over conventional restorative materials.

In this study, the paper will show an investigation based on the mechanical properties of cotton fabric and Coconut Husk composites and develop a biodegradable composite material. Mechanical tests such as Tensile, Compression, and Three-point flexural. Furthermore, they will be compared to the E- Glass sandwich composite based on the acquired physical properties. The reason why cotton fabric and coconut husk were chosen is due to the advantage of being environment friendly, low cost and low weight. This gives an advantage to both structural application and maintaining a green environment. Recently composite materials have been brought up in the aeronautical industry, as there has been a wide utilization of synthetic fibres and non-biodegradable plastics at the same time creating a threat to the environment, mainly because of the disposal problems, bad recycling and non-biodegradability characteristics. Natural fibres have been found as a solution to this problem. Mechanical investigation of the biodegradable composite was conducted by performing flexural, compression and tensile tests. The analysis showed that the strength to weight ratio for the composites increased by the inclusion of natural fibres. This property of better strength to weight ratio could be used to obtain better material for industries such as marine, aviation, and space.

This experimental investigation explored the optimisation of silane treatment of surface-modified S-2 Glass fibres in restorative dental composites for improved mechanical performance. The influence of optimum amount of silane to improve the interfacial adhesion at the fibre-matrix interfaces and its effect on the mechanical properties of the restorative composites were explored.S-2 Glass fibres of 5 μm diameter and 250 μm length were surface modified using the acid etching technique. The etched fibres were then treated with either 3-methacryloxypropyltrimethoxysilane (3-MPS), 3-Glycidoxipropyltrimethoxysilane (3-GPS) or 8-methacryloxyoctyltrimethoxysilane (8-MOTS) at varying molar % / wt% concentrations. Fibres that were not silanised with any silane coupling agents were used as the control sample. The silanol content of each mixed silane was observed using Fourier transform infrared (FT-IR) spectroscopy analysis. Fibres (5 wt%) with optimised molar% / wt% silane coupling concentration were added to UDMA/TEGDMA dental resin. Mechanical properties such as flexural strength, flexural modulus, and the breaking energy of the materials were evaluated using a comprehensive experimental programme.FTIR spectrum of glass fibre silanised with each silane coupling agent revealed many peaks from 3800 to 1400 cmThe interfacial adhesion between the fibre and the resin due to silane coupling agents has helped to improve the mechanical properties of the fibre-reinforced dental composite. This is the first experimental study to provide a thorough investigation into the significance of the optimal use of silane coupling agents to treat the S-2 Glass fibres and subsequently the influence on the mechanical performance of the fibre-reinforced flowable dental composites.

The aim of researches conducted in thermal protection systems in aeronautics and astronautics field of engineering is to generally defend the craft from high heat loads during operation while operating at hypersonic regimes in air and space. The motive of the following composition is to draft a review analysis on ablative heating materials as thermal protective equipment on reusable planetary/atmospheric re-entry vehicles such as a space shuttle, an inter-continental ballistic missile, or a hypersonic cruise missile. The heat liberation can cause much damage to the aircraft/spacecraft whilst operation which is generally beyond repair. It is therefore of utmost importance to research multiple strategy to reduce the effect of shockwaves damage to spacecraft/aircraft materials. We shall initiate the analysis by mentioning some re-usable tile thermal protection system types such as high temperature reusable surface insulation tiles (H.R.S.I), fibrous refectory composite insulation tiles (F.R.C.I), low temperature reusable surface insulation tiles (L.R.S.I) and gradually move on to ablative thermal protection systems with the advent of reinforced carbon-carbon’s application in astronautics and aeronautics respectively.

There is a rising agreement within space debris group that balance is inadequate to force the orbiting debris masses and that ensuring a protected future for space activities, which require the advancement and organization of frameworks that effectively eject space-junk from Earth’s orbit. Prescient examinations demonstrate that if people do not make a move to control the space flotsam and jetsam masses, an expanding number of unexpected crashes between orbiting objects will prompt the runaway development of Space-debris in Earth’s orbit. It goes ahead to examine the political difficulties in creating and executing viable frameworks and finishes up with proposals for sorting out and dealing with a space debris evacuation program in the present geopolitical condition. This paper starts with an outline of the developing space trash issue to define the need to create and convey dynamic evacuation frameworks during the upcoming years. Issues will likewise emerge in partitioning the foreseen high expenses, as few nations are in charge of the larger part of the space debris masses, yet all countries will profit by its removal.

Global Atmospheric Analysis is based upon varies remote sensing techniques. One of the key factors for this kind of survey is Land Surface Temperature (LST). LST surveys are utilized for the development of predicted climate models, urban covered land-atmosphere, supervising vegetation and monitoring Global Warming. It gives us the data ranging from spatial to temporal variation for the land. Along with LST; Land Surface Emissivity is also a vital factor in surveys related to earth surface characteristics. These values are required to utilize in the method applied to this survey. Extensive possibilities for surveying the surface through remote sensing is provided by the LANDSAT series. The analysis of this survey is based upon the images taken of Dubai and it is achieved by utilizing Thermal Infrared Sensor (TIS) and Operation Line Imager (OLI) satellite sensor records. Thermal band images obtained from LANDSAT 8 are processed in QGIS software by using band 10 data.

Nowadays we are finding newer and newer efficient ways to carry out tasks by using the concept of automation and machinery combined. One of the ways to accomplish such a task is by using a quadcopter. It can accomplish a vertical trip in a steady way and be utilized to screen or gather information in an explicit area, for example, mapping landscapes. Mechanical advances have diminished the expense and increment the execution of the low power microcontrollers that enabled the overall population to build up their very own quadcopter. The objective of this venture is to manufacture, change, and make enhancements in the control configuration of the quadcopter to acquire stable flight. The objective of this paper is to incorporate Wi-Fi communication in controlling the quadcopter by using an inexpensive microcontroller as a flight computer and develop an HTML webpage to receive the video-feed transmitted from the mobile phone camera fixed on the quadcopter.

Ion propulsion is based on the concept of the collisions of neutral atoms with high energy electrons which causes ionization, this ionization then releases the positive ion allowing it to accelerate through the electrodes causing them to shoot out with high speeds. Ion propulsion technology took 50 years to produce until October 24 of 1998. In this year the first ever spacecraft to utilize ion propulsion technology to propel it was the Deep Space 1. From that year on ion propulsion technology was steadily increasing in popularity due to the fact that ion propulsion does not have a need for moving parts therefore less stress on the body/fuselage of any space/aircraft. Ion propulsion technology through the use of xenon as a propellant led NASA to the proposal of their newest project named N.E.X.T. NASA's Evolutionary Xenon thruster. NEXT system opens a door to a wide range of office of space science missions such as Saturn Ring Observer, and Comet surface sample collection mission.

In recent time published research indicates only limited works have been addressed in the field of machining properties with respect to ecofriendly materials. However, characteristic natural fibers have extraordinary potential for decreasing the materials weight, bio-degradable, and bringing down material cost. The aim of the present work is to focus mainly on the abrasive waterjet machining of Kevlar composite and hybridized Kevlar-Jute fiber Reinforced Epoxy Composite. An endeavor is made to minimize the use of manufactured synthetic Kevlar fiber by incorporating natural jute strands to such an extent that the resultant hybrid composite shows superior quality when compared with single fortifications of jute strands. Composite laminates are synthesized using hand lay-up technique. The test specimen were synthesized and characterization has been performed according to the American Society for Testing and Materials (ASTM) standards. The composites were synthesized using Epoxy Resin (Razeen® LR 1150) and Hardener (ADDcure® 91618) along with reinforcing fiber Jute & Kevlar. Finally, the design of experiments is conducted using Taguchi Approach, wear testing using Taber Abrader Model 5135 for checking the wear formation in the material for different number of cycles, statistical models are analyzed using Analysis of variance (ANOVA), and microscopic investigation is carried out to examine the internal structure of ruptured surfaces and its failure morphology using scanning electron microscopy (SEM).

The implementation of composite materials have widely increased in the recent years in the field of aerospace and aeronautical engineering. This is mainly due to advanced mechanical and physical properties that is found in the composite structures such as ease of fabrication, good electrical properties, better thermal properties and above all higher strength to weight ratio when compared to metals. A sandwich composite consists of multiple layers of a composite mixture consisting of matrix and fibers. In this research an analysis on various hybridized sandwich composites with different core were subjected to simple testing with constant unit load on SOLID185 offered by the software ANSYS Mechanical APDL 18.1 to compute displacements and stresses. The ratio of young’s moduli of layers and its effects on the displacements and stresses were studied.

Noise arising from aircrafts while it is in operation is a big concern in this day and age. This report aims to analyse and reduce the noise production from the nozzles of an Ejector jet engine with the help of Passive Noise Suppression. The research will take use of an existing model and a new variation model by printing it through a 3D printer and undergoing it through acoustic test. This Research will help us better compare the differences in noise production with the existing model and the newer model and then put up these data for future studies. The experiment would require to perform an experiment involving measuring of input and output decibels, frequency comparison when sound of a constant frequency is sent through customized nozzles in order to read the same on the other end of the nozzle. This in turn will provide the necessary results needed for the experiment and then would be compared with each other to form the basis of the experiment. The conclusion would be that the model with the least amount of facets and the least amount of chevrons, 4 facet and 4 facet chevrons, would produce the least amount of noise due to its design characteristics

Maintaining surveillance is no easy job, neither is chasing criminals nor looking for kids or elderly people who are lost in crowded areas. This report aims to propose a viable solution for the aforementioned issue. The proposal encompasses the working of an Unmanned Aerial Vehicle (UAV) with an add-on of face recognition software created by us. The process flow includes inputting the face of the person (either blacklisted or lost) into the software followed by drone run to scan for the inputted faces and providing live alerts when a match is found along with their location. The application of this project can be extended to look humans in closed environments- such as exhibition halls, pattern tracking, and public safety surveillance. UAVs are the future and using them for such applications help reduce the human efforts, thereby making things easier and human error-free.

For decades composite materials have been used in aviation industry, but the forth coming generations of airframe structures will be the first in which the major fundamental component are fabricated from composites instead of metals. The fabrication of Three Dimensional spacer fabric is a recently established concept where the surfaces of fabric are strongly interlinked to each other by vertical pile fibers which are interwoven using different techniques with the skins. Hence as a result of this new technique, better skin-core debonding resistance, superior integrity and perfect durability is achieved. In addition, the interstitial space of the construction can be filled up with foams to provide synergistic support with vertical piles. This paper discusses on the fabrication of the composites and in the secondary stage understanding the mechanical properties of the specimen by flexural testing and in the final stage comparison of test results.

Unmanned Ariel vehicles are very exciting for all, and can be used by anyone; it provides a new perspective to the modern world. Misuse of drone's leads to warfare then epitomizes altogether different effect and possibly followed uncontrolled threat to society at large. UAE have been coming up with regulation to restrict and monitor the use of non-commercial usage on emerging technologies. The paper aims to address regulation, requirements, restriction, and to discuss legislation on civil aviation and flight activities on drones.