Sahith Reddy Madara | University of Toulouse (original) (raw)

Papers by Sahith Reddy Madara

72nd International Astronautical Congress, Dubai, United Arab Emirates, 25-29 October 2021., 2021

72nd International Astronautical Congress (IAC), Dubai, United Arab Emirates, 25-29 October 2021., 2021

This paper will look into the factors that affect the correlation between the Jupiter-Io observed... more This paper will look into the factors that affect the correlation between the Jupiter-Io observed radio events and the Sun radio bursts using the Sharjah Decametric Radio Telescope (SDRT) located at the Sharjah Academy for Astronomy, Space Sciences, and Technology in the United Arab Emirates. The SDRT has been operational since 2019 and is sponsored by the UAE Space Agency. We analyze the number of Jupiter and Sun events to the Sun cycle's predicted events from 2019 to 2020 related to the solar cycles 25 and 25. One factor that affected our Jovian-Io observations is the apparent angle between the Sun and Jupiter. We have noticed that these events are at a maximum during opposition and minimum during the conjunction. Some Jovian events were predicted by the Radio-Jupiter Pro III software but were not detected by the SDRT. We show a modest correlation between the observed solar flares and the trapped particle flux at Io's orbit responsible for Jupiter's radio Land S-bursts. These observations are essential to understand the Jupiter-Io exchange of particles due to its moon Io volcanic nature and Jupiter's intense magnetic field enhanced by the solar radio bursts observed by the SDRT.

72nd International Astronautical Congress (IAC), Dubai, United Arab Emirates, 25-29 October 2021., 2021

This paper studies the correlation between the number of sunspots observed by the Sharjah Optical... more This paper studies the correlation between the number of sunspots observed by the Sharjah Optical Observatory (SOO) and the solar radio bursts observed by the Sharjah Decametric Radio Telescope (SDRT) following the new 25 th solar cycle. Both observatories (SOO and SDRT) are located at the Sharjah Academy for Astronomy, Space Sciences, and Technology (SAASST) in the United Arab Emirates. As the Sun's magnetic field changes, the Sun's activity changes. The start of a solar cycle coincides with a solar minimum, referred to as the quiet radio Sun when the Sun has the least number of sunspots. Our SDRT observations reveal that the last quiet Sun phenomenon occurred between 2018 and 2019, i.e., the end of the 24 th solar cycle and the beginning of the new 25 th solar cycle. In 2020, solar activity and the number of sunspots saw a surge. The half period of the solar cycle is the solar maximum, or once the Sun has the highest number of sunspots. The 24 th solar cycle ended in December 2019 when the average number of sunspots achieved its minimum, and the first sunspots of the new cycle started to occur. Our preliminary results showed a strong correlation between the number of sunspots observed by the SOO and the detected radio bursts by the SDRT system. The two observatories' optical and radio contribute to the SAASST Space Weather program as part of the UAE Space Agency's vision to have a national program related to solar observations.

72nd International Astronautical Congress (IAC), Dubai, United Arab Emirates, 25-29 October 2021., 2021

In this paper, we are reviewing the following trajectory methods, for the above-mentioned asteroi... more In this paper, we are reviewing the following trajectory methods, for the above-mentioned asteroids, with origins at Earth: [(i) gravity assist planetary swing-by, (ii) Hohmann transfer, (iii) Lambert's problem] while considering the spacecraft's ToF (time of flight), total fuel usage (ΔV), and the final orbital elements. Through a comparison between the trajectory methods of each potential target asteroid that we have listed above, and the corresponding estimate of energy needed for missions, we provide a thorough analysis beneficial for future missions. Further, we compare and calculate parameters like ΔV and ToF to reach these asteroids (flyby or rendezvous) using gravity assist (G), Solar Electric Propulsion (SEP), and SEP+G trajectory methods. The paper provides a detailed study particularly focusing on the trajectory design methods for asteroid missions.

71st International Astronautical Congress (IAC), CyberSpace Edition, 12-14 October 2020, 2020

SharjahSat-1 is a collaborative research project by the Sharjah Academy for Astronomy, Space Scie... more SharjahSat-1 is a collaborative research project by the Sharjah Academy for Astronomy, Space Science, and Technology (SAASST), University of Sharjah (UoS), Istanbul Technical University (ITU), and Sabanci University (SU). The 3U+ CubeSat will implement an improved X-ray Detector (iXRD), as the primary payload, and a secondary payload, which is a system of two optical cameras. The X-ray detector's objective is to detect hard X-rays from very bright X-ray sources, and to study the solar coronal holes, whereas the camera system will provide a low-resolution remote sensing application. Sharjah-Sat-1 would be the first CubeSat mission to be developed by the SAASST team and UoS students, which aims to build capacities and expertise that would be of much value for the following future CubeSat missions. The thermal analysis of the Sharjah-Sat-1 is a crucial step to assure the safety of the internal systems of the satellite from the harsh conditions of outer space. Each component of the satellites has different operating temperature requirements. Since passive thermal control methods are mostly used for smaller satellites, and no means of active thermal control systems are to be used on Sharjah-Sat-1, it is critical to ensure that each component would remain in the allowable temperature range that it was designed to operate in throughout the satellite's mission. According to two different orbits that are chosen based on the suitable launching options available in the Q1 of 2021 and Q2 of 2021, a detailed thermal model of Sharjah-Sat-1 is developed using commercial software. The simulations are carried out to help evaluate mission viability in different orbits in relation to subsystems' temperature limits. The thermal tests will be performed to support modelling and analysis in the thermal vacuum chamber of ITU-Space Systems Design and Test Laboratory. The simulated scenarios on the different orbits will enable us to choose the best orbit, in terms of assuring the safety of the satellite’s internal systems, since an appropriate thermal analysis design could potentially save the mission from failure and extend mission lifetime. Both orbits analyzed are found to be adequate for the mission.

71st International Astronautical Congress (IAC) – The CyberSpace Edition, 12-14 October 2020, 2020

In recent years, nanosatellites have experienced rapid development in light of the launch of hund... more In recent years, nanosatellites have experienced rapid development in light of the launch of hundreds of them in Low-Earth Orbit (LEO). As part of the research investigations conducted in spacecraft operations, the Sharjah Academy for Astronomy, Space Sciences, and Technology (SAASST) is currently developing Sharjah-Sat-1. The 3U X-ray Detector CubeSat is set to launch in the second quarter of 2021. A Ground Station control system is essential for communicating with Sharjah-Sat-1 to facilitate receiving telemetry and sending commands. In support of such a mission and future ones, a full-fledged ground station has been built, which can be useful for multiple satellite missions. The ground station is currently operating on UHF/VHF frequency bands with high gain. An S-band dish antenna system is planned to be installed soon to augment ground station capability to support ongoing CubeSat operations. The Ground Station's hardware is composed of several components, i.e., UHF/VHF antennas, a Software Defined Radio (SDR) transceiver, a suitable Rotator with Elevation-Azimuth dual controller, and a Rotator control interface. As for the software employed, it is mainly the Ham Radio Deluxe package that consists of a Ham Radio Deluxe (HRD) satellite tracking, HRD rotator control, and an HRD rig, along with a custom-designed ground station console software for Sharjah-Sat-1 related data and commands. With the implementation of this system, the ground station is fully automated while tracking and can also be remotely controlled. Besides its satellite tracking use, the ground station will provide practical training for university students in anticipation of future small satellite operations.

71st International Astronautical Congress (IAC) – The CyberSpace Edition, 2020

An array consisting of four dual dipole antennas has been built at the Sharjah Academy for Astron... more An array consisting of four dual dipole antennas has been built at the Sharjah Academy for Astronomy, Space Sciences, and Technology (United Arab Emirates) to conduct decametric radio observations. Based on the NASA radio Jove design, the array spans an area of about 400 square meters. The receiver of the array is designed to operate at 20.1 MHz to conduct observations of the Jupiter-Io interactions, solar bursts, and the background radio emission of the Milky Way. The main aim is to construct a system to initiate undergraduate students to radio astronomy research. In this paper, we report on the initial observations of several Jupiter-Io radio outbursts. These radio outbursts outline the exchange of charged particles between Jupiter and its closest moon Io through Jupiter's intense magnetic field. These observations are essential to understand the physical mechanisms that can cause the Jovian radio emission, especially the cyclotron maser emission mechanism. In this process, the charged particles that result from Io volcanic eruptions spiral around the Jupiter-Io magnetic field bridge to emit a hollow conical beam of radiation. Our long-term decametric radio observations, combined with other long-wavelength observations, can help us understand the Jupiter-Io interaction better. The array is located at 25.286 degrees N, 55.463 degrees E in the city of Sharjah. The UAE Space Agency has funded this project under grant fund number J03-2016-03.

Elsevier Materials Today, 2020

In abrasive waterjet machining (AWJM), water acts as an accelerating medium and abrasive particle... more In abrasive waterjet machining (AWJM), water acts as an accelerating medium and abrasive particles are used for cutting materials. This is a cost effective and environmentally friendly technique. Kevlar 49 is one of the most commonly used composite materials and is extensively used in aerospace industries where high strength-to-weight ratio and excellent corrosion resistance are required. This material can be processed by only by abrasive waterjet machining technology due to its high strength. The quality of AWJM is depending upon the process parameters of this technology. This paper provides an experimental investigation for the performance analysis of process parameters on machining Kevlar 49 using abrasive waterjet technology. In this paper mathematical model is also being developed to predict the surface roughness to find the relation between the inputs and the outputs. The first part predicts the surface roughness based on the pressure and the traverse speed whereas the second part indicates the surface roughness variation with standoff distance and the mass flow rate. The model is developed with the back-propagation algorithm using artificial neural network (ANN). The initial weights are assumed, and the algorithm predict and update the weights until it could predict the actual value. The final model is used to verify the results and is found that it is more than 95% accurate. Hence this model is used to study surface roughness by varying all the parameters theoretically.

Elsevier: Materials Today, 2020

Present study deals with hot forging behavior of the sintered AISI 8740 powder metallurgy steels ... more Present study deals with hot forging behavior of the sintered AISI 8740 powder metallurgy steels through powder metallurgy route. These steels extensively used for automobile application for its strength and elongation. Green compacts were fabricated with aspect ratios 1.28, 0.92 and 0.55. These green compacts were fabricated using appropriate die set assembly with 0.6 MN capacity Universal testing machine at 550 ± 10 MPa pressure and subsequently sintered at an elevated temperature in a protective atmosphere using Muffle furnace. Green compacts were forged and analysed with different densification and properties evaluation. Structure property correlation were analysed systematically. The fractography of all compacts show fine dimples and cleavage kind of fracture that confirms mixed mode of fracture due to the existence of multi-phase combination of different alloying elements.

Elsevier Materials Today: Proceedings, 2020

This study shows the vibration and low velocity impact behaviour of AlMg4.5Mn reinforced nanoclay... more This study shows the vibration and low velocity impact behaviour of AlMg4.5Mn reinforced nanoclay nanocomposites at room temperature. Composite samples with different weight percentage of nanoclay were fabricated using liquid state synthesis casting technique, to achieve homogeneous dispersion of Nanoclay. The material characterization was studied by Scanning Electron Microscope (SEM) and Energy-dispersive X-ray spectroscopy (EDS). From the study it was concluded that the Hardness value of the aluminium alloy reinforced nanoclay was increased in addition of nanoclay weight percentage. The natural frequencies of impacted AlMg4.5Mn reinforced nanoclay composites was found to be increased in addition of 2.5 wt% nanoclay.

Elsevier Materials Today: Proceedings, 2020

Ti-6Al-4V is classified among the most commonly used Ti-alloys and is extensively used in aerospa... more Ti-6Al-4V is classified among the most commonly used Ti-alloys and is extensively used in aerospace and medical industries where low-density, high strength and outstanding corrosion resistance are required.
This material cannot be processed by conventional machining methods because of its high strength. Abrasive Waterjet Machining, abbreviated as AWJM, is an unconventional machining process suitable for machining Ti-6Al-4V as it generates less heat affected zone. The quality of AWJM is governed by process parameters, the selection of these parameters is critical in this technology to achieve the desirable output measures. This paper provides an experimental investigation for the performance analysis of process parameters on machining Ti-6Al-4V using abrasive waterjet technology. In order to select appropriate parameters, a mathematical equations were developed using Regression Investigation Method (RIM) Artificial Neural Network (ANN) procedures. Based on the input and output data collected from the experiments, modelling is done and tested for the different set of data to ensure the accuracy. These mathematical models can be used to identify the static and dynamic behavior of the process. These models will further help in simulating the process, expanding the design facilities and studying the physical and chemical variation in the process. Models provide understanding the operations, control methods and the possible optimization. The developed models also help in documenting the performance of the existing system.

Elsevier Materials Today: Proceedings, 2019

Abrasive waterjet machining (AWJM) is one of the unconventional machining practices and is used w... more Abrasive waterjet machining (AWJM) is one of the unconventional machining practices and is used widely in industries. The key output performance measures in this technique are depth of cut and surface roughness. This paper presents the experimental investigation on machining conditions of abrasive waterjet process in machining mild steel. Taguchi's method of design of experiments was used to select input process parameters by varying water pressure, traverse speed, abrasive mass flow rate and standoff distance. The depth of cut and surface roughness were measured using Sigma Scope 500 profile projector and surface roughness tester respectively. After getting the required data from the experimental setup the same data is fed to the artificial neural networks and back propagation algorithm procedure is used to train the data using MATLAB programming package. It is observed that the artificial neural network (ANN) model was able to foresee the new set of data. This mathematical modelling tool can be used to predict dynamic varying different types of input to identify the stability of the system.

Elsevier Materials Today: Proceedings, 2019

The present study deliberates the optical properties of vacuum evaporated Pb 15 Se 85Àx Ge x (x =... more The present study deliberates the optical properties of vacuum evaporated Pb 15 Se 85Àx Ge x (x = 0, 3, 6 at. %) thin films. The absence of sharp peaks in XRD hints about the non-crystalline nature. Transmission spectra (at normal incidence) are acquired in the spectral region of 400-2400 nm. A blue-shift in the transmission spectra hints about the increase in the band-gap. Experimentally, the band-gap is calculated using Tauc-extrapolation method. The band-gap transition is indirect and is found to increase with the substitution of Se by Ge in the glassy alloy. The optical density and penetration depth are calculated using the absorption coefficient data. The penetration depth increases with the increase in Ge-content and the cutoff wavelength shows a blue shift. The obtained optical properties are correlated with the physical parameters. Considering the topological model, it is revealed that the system shows a transition from floppy to the intermediate region. Lone pair electron value is greater than 3 and that favours the glass formation. The distribution of bonds in the present system is also examined using chemical bond approach (CBA) model and the system's cohesive energy (CE) is also calculated. The increase in cohesive energy shows that the average stabilisation energy of the system is increasing. This also reflects the increased value of experimentally calculated optical band-gap. The average heat of atomization also shows an increase with Ge addition. Conduction band potential seems to shift away from the Fermi level. The results are discussed based on the change in bond energy, bond length, total system energy and topo-logical models applied on the system.

Springer Nature Singapore (Internet of Things and Analytics for Agriculture, Volume 2, Studies in Big Data 67), 2019

This paper discusses key challenges faced by transformation of smart cities and integration of gr... more This paper discusses key challenges faced by transformation of smart
cities and integration of green technologies, initiatives, and existing systems that are in place to solve for these challenges. With overpopulation, fast urbanization, and environmental changes, powerful administration of trees and plants is required like never before. We present an Internet of things (IoT)-based smart tree management
architecture for cities which is able to track various characteristics of a given tree such as the air quality, sunlight level, sound pollution level, and other important characteristics for efficient city planning, afforestation plans, and higher quality produce. We divide the solution into three sections: The Sensor Node, The Cloud Integration, and User Experience. We have developed a working prototype using a Raspberry Pi and a mobile application consisting of an intuitive user interface that lets users and farm owners get information about a certain tree and view its information and alerts. We utilize low-power wide-area network modules for the connectivity of the various sensors to the cloud. A map view is also developed which consists of various filters that let city authorities understand the distribution of healthy and damaged trees across the city accompanied by an extensive customized dashboard. A prototype of a
green smart tree management system based on the Internet of things is discussed and implemented. The paper describes the functions and actual characteristics of each system component in detail. The experimental results suggest the feasibility of the application to enable the development of smart cities across theworldwhich will play a key role in decreasing pollution levels across the city and increasing afforestation in areas that require it the most. This solution can be useful in spreading awareness among citizens on the importance of afforestation and proper management of trees in the city and can help farmers in rural areas to avoid hours of manual inspection and labor spent in inspecting the health of their farms.

IOP Journal of Physics: Conference Series, 2019

Abrasive waterjet cutting is one of the unconventional methods used to cut some of the difficult ... more Abrasive waterjet cutting is one of the unconventional methods used to cut some of the difficult to cut materials. In certain materials this method has proved to give better results compared to the conventional methods. In this model the water jet cutting is done on hastelloy using the three parameters which are abrasive mass flow rate, traverse speed, and the stand-off distance. The mathematical modelling to predict the kerf width based on these three input parameters is discussed in this paper. As the relation between the input and the output parameter is non-linear in nature neural network back propagation algorithm is used for the prediction. Here the experiment is conducted using waterjet cutting machine and the data's like surface roughness, metal removal rate, kerf width and the kerf angle data are collected. Both the input and the output parameters are fed to the neural network toolbox programmed in the MATLAB. After 1000 iterations it has been found that the prediction is closer to the actual value. The mathematical constants which is the weight matrix is used to test the new set of data for accuracy. It has been found that the prediction is more accurate compared to the conventional methods. This experiment is based Taguch's design which uses the above three parameters to cut the material. This paper also discusses on the predication of surface roughness of hastelloy created due to the variation in these parameters.

International Journal of Recent Technology and Engineering (IJRTE), 2019

Abrasive waterjet cutting is one of the unconventional cutting processes capable of cutting exten... more Abrasive waterjet cutting is one of the unconventional cutting processes capable of cutting extensive range of difficult-to-cut materials. This paper assesses the impact of process parameters on surface roughness which is a significant machining performance measure in abrasive waterjet cutting of hastelloy. The experimental parameters were selected based on Taguch's design of experiments. Experiments were conducted in varying nozzle traverse speed, abrasive mass flow rate and standoff distance for cutting hastelloy using abrasive waterjet cutting process. The effects of these parameters on surface roughness have been discussed.

Self-healing materials are artificial or synthetically created substances that have the built-in ... more Self-healing materials are artificial or synthetically created substances that have the built-in ability to automatically repair damage to themselves without any external diagnosis of the problem or human intervention. This article presents the current research and developments in self-healing composite materials. A detailed study is conducted on various types of self-healing composites with their self-healing mechanisms. The applications of self-healing materials in various fields including space sector is also discussed. Economics and Future outlooks for self-healing smart materials is highlighted at the end of the article. This research article will be useful to manufacturers, policy makers and researchers widely.

Key Words: Self-Recuperating Structures; Ionomeric Self-Healing; Anticorrosion Coating; Fatigue Resistance; Surface Cracks; Intrinsic and Extrinsic Self-Healing

The three dimensional spacer textures, comprise of two bi-directional woven texture surfaces, whi... more The three dimensional spacer textures, comprise of two bi-directional woven texture surfaces, which are mechanically associated with vertical sewed heaps. The three dimensional spacer textures can be made of glass fiber, carbon fiber or basalt fiber. The Three Dimensional Composites are classified based on the different factors depending on the orientation of the yarn, the yarn sets and the geometry. The three dimensional composites have multiple layers and hence they overcome delamination, which is a common defect in two dimensional composites. Nevertheless, these composite materials have relatively lower transverse properties and also, have size and thickness limitations. This literature reviews on several important published literatures on three dimensional composite materials. The review studies the numerous effects that lead to the failure of the composite material.

International Journal of Scientific & Engineering Research, 2017

The increasing availability of green power enables electricity customers to accelerate installati... more The increasing availability of green power enables electricity customers to accelerate installation of renewable energy technologies. This review paper provides various approaches towards power market worldwide. Impact of power generation on international trade are discussed to understand various opportunities in green power generation. Current trends used in green power generation with scope for future advancements are also discussed in detail. Also the various challenges in this field with economic and ecological effects are addressed. This review paper will help researchers and policy makers widely.

Index Terms— Green Power, wind energy, solar energy, sustainability, renewable energy, international trade

72nd International Astronautical Congress, Dubai, United Arab Emirates, 25-29 October 2021., 2021

72nd International Astronautical Congress (IAC), Dubai, United Arab Emirates, 25-29 October 2021., 2021

This paper will look into the factors that affect the correlation between the Jupiter-Io observed... more This paper will look into the factors that affect the correlation between the Jupiter-Io observed radio events and the Sun radio bursts using the Sharjah Decametric Radio Telescope (SDRT) located at the Sharjah Academy for Astronomy, Space Sciences, and Technology in the United Arab Emirates. The SDRT has been operational since 2019 and is sponsored by the UAE Space Agency. We analyze the number of Jupiter and Sun events to the Sun cycle's predicted events from 2019 to 2020 related to the solar cycles 25 and 25. One factor that affected our Jovian-Io observations is the apparent angle between the Sun and Jupiter. We have noticed that these events are at a maximum during opposition and minimum during the conjunction. Some Jovian events were predicted by the Radio-Jupiter Pro III software but were not detected by the SDRT. We show a modest correlation between the observed solar flares and the trapped particle flux at Io's orbit responsible for Jupiter's radio Land S-bursts. These observations are essential to understand the Jupiter-Io exchange of particles due to its moon Io volcanic nature and Jupiter's intense magnetic field enhanced by the solar radio bursts observed by the SDRT.

72nd International Astronautical Congress (IAC), Dubai, United Arab Emirates, 25-29 October 2021., 2021

This paper studies the correlation between the number of sunspots observed by the Sharjah Optical... more This paper studies the correlation between the number of sunspots observed by the Sharjah Optical Observatory (SOO) and the solar radio bursts observed by the Sharjah Decametric Radio Telescope (SDRT) following the new 25 th solar cycle. Both observatories (SOO and SDRT) are located at the Sharjah Academy for Astronomy, Space Sciences, and Technology (SAASST) in the United Arab Emirates. As the Sun's magnetic field changes, the Sun's activity changes. The start of a solar cycle coincides with a solar minimum, referred to as the quiet radio Sun when the Sun has the least number of sunspots. Our SDRT observations reveal that the last quiet Sun phenomenon occurred between 2018 and 2019, i.e., the end of the 24 th solar cycle and the beginning of the new 25 th solar cycle. In 2020, solar activity and the number of sunspots saw a surge. The half period of the solar cycle is the solar maximum, or once the Sun has the highest number of sunspots. The 24 th solar cycle ended in December 2019 when the average number of sunspots achieved its minimum, and the first sunspots of the new cycle started to occur. Our preliminary results showed a strong correlation between the number of sunspots observed by the SOO and the detected radio bursts by the SDRT system. The two observatories' optical and radio contribute to the SAASST Space Weather program as part of the UAE Space Agency's vision to have a national program related to solar observations.

72nd International Astronautical Congress (IAC), Dubai, United Arab Emirates, 25-29 October 2021., 2021

In this paper, we are reviewing the following trajectory methods, for the above-mentioned asteroi... more In this paper, we are reviewing the following trajectory methods, for the above-mentioned asteroids, with origins at Earth: [(i) gravity assist planetary swing-by, (ii) Hohmann transfer, (iii) Lambert's problem] while considering the spacecraft's ToF (time of flight), total fuel usage (ΔV), and the final orbital elements. Through a comparison between the trajectory methods of each potential target asteroid that we have listed above, and the corresponding estimate of energy needed for missions, we provide a thorough analysis beneficial for future missions. Further, we compare and calculate parameters like ΔV and ToF to reach these asteroids (flyby or rendezvous) using gravity assist (G), Solar Electric Propulsion (SEP), and SEP+G trajectory methods. The paper provides a detailed study particularly focusing on the trajectory design methods for asteroid missions.

71st International Astronautical Congress (IAC), CyberSpace Edition, 12-14 October 2020, 2020

SharjahSat-1 is a collaborative research project by the Sharjah Academy for Astronomy, Space Scie... more SharjahSat-1 is a collaborative research project by the Sharjah Academy for Astronomy, Space Science, and Technology (SAASST), University of Sharjah (UoS), Istanbul Technical University (ITU), and Sabanci University (SU). The 3U+ CubeSat will implement an improved X-ray Detector (iXRD), as the primary payload, and a secondary payload, which is a system of two optical cameras. The X-ray detector's objective is to detect hard X-rays from very bright X-ray sources, and to study the solar coronal holes, whereas the camera system will provide a low-resolution remote sensing application. Sharjah-Sat-1 would be the first CubeSat mission to be developed by the SAASST team and UoS students, which aims to build capacities and expertise that would be of much value for the following future CubeSat missions. The thermal analysis of the Sharjah-Sat-1 is a crucial step to assure the safety of the internal systems of the satellite from the harsh conditions of outer space. Each component of the satellites has different operating temperature requirements. Since passive thermal control methods are mostly used for smaller satellites, and no means of active thermal control systems are to be used on Sharjah-Sat-1, it is critical to ensure that each component would remain in the allowable temperature range that it was designed to operate in throughout the satellite's mission. According to two different orbits that are chosen based on the suitable launching options available in the Q1 of 2021 and Q2 of 2021, a detailed thermal model of Sharjah-Sat-1 is developed using commercial software. The simulations are carried out to help evaluate mission viability in different orbits in relation to subsystems' temperature limits. The thermal tests will be performed to support modelling and analysis in the thermal vacuum chamber of ITU-Space Systems Design and Test Laboratory. The simulated scenarios on the different orbits will enable us to choose the best orbit, in terms of assuring the safety of the satellite’s internal systems, since an appropriate thermal analysis design could potentially save the mission from failure and extend mission lifetime. Both orbits analyzed are found to be adequate for the mission.

71st International Astronautical Congress (IAC) – The CyberSpace Edition, 12-14 October 2020, 2020

In recent years, nanosatellites have experienced rapid development in light of the launch of hund... more In recent years, nanosatellites have experienced rapid development in light of the launch of hundreds of them in Low-Earth Orbit (LEO). As part of the research investigations conducted in spacecraft operations, the Sharjah Academy for Astronomy, Space Sciences, and Technology (SAASST) is currently developing Sharjah-Sat-1. The 3U X-ray Detector CubeSat is set to launch in the second quarter of 2021. A Ground Station control system is essential for communicating with Sharjah-Sat-1 to facilitate receiving telemetry and sending commands. In support of such a mission and future ones, a full-fledged ground station has been built, which can be useful for multiple satellite missions. The ground station is currently operating on UHF/VHF frequency bands with high gain. An S-band dish antenna system is planned to be installed soon to augment ground station capability to support ongoing CubeSat operations. The Ground Station's hardware is composed of several components, i.e., UHF/VHF antennas, a Software Defined Radio (SDR) transceiver, a suitable Rotator with Elevation-Azimuth dual controller, and a Rotator control interface. As for the software employed, it is mainly the Ham Radio Deluxe package that consists of a Ham Radio Deluxe (HRD) satellite tracking, HRD rotator control, and an HRD rig, along with a custom-designed ground station console software for Sharjah-Sat-1 related data and commands. With the implementation of this system, the ground station is fully automated while tracking and can also be remotely controlled. Besides its satellite tracking use, the ground station will provide practical training for university students in anticipation of future small satellite operations.

71st International Astronautical Congress (IAC) – The CyberSpace Edition, 2020

An array consisting of four dual dipole antennas has been built at the Sharjah Academy for Astron... more An array consisting of four dual dipole antennas has been built at the Sharjah Academy for Astronomy, Space Sciences, and Technology (United Arab Emirates) to conduct decametric radio observations. Based on the NASA radio Jove design, the array spans an area of about 400 square meters. The receiver of the array is designed to operate at 20.1 MHz to conduct observations of the Jupiter-Io interactions, solar bursts, and the background radio emission of the Milky Way. The main aim is to construct a system to initiate undergraduate students to radio astronomy research. In this paper, we report on the initial observations of several Jupiter-Io radio outbursts. These radio outbursts outline the exchange of charged particles between Jupiter and its closest moon Io through Jupiter's intense magnetic field. These observations are essential to understand the physical mechanisms that can cause the Jovian radio emission, especially the cyclotron maser emission mechanism. In this process, the charged particles that result from Io volcanic eruptions spiral around the Jupiter-Io magnetic field bridge to emit a hollow conical beam of radiation. Our long-term decametric radio observations, combined with other long-wavelength observations, can help us understand the Jupiter-Io interaction better. The array is located at 25.286 degrees N, 55.463 degrees E in the city of Sharjah. The UAE Space Agency has funded this project under grant fund number J03-2016-03.

Elsevier Materials Today, 2020

In abrasive waterjet machining (AWJM), water acts as an accelerating medium and abrasive particle... more In abrasive waterjet machining (AWJM), water acts as an accelerating medium and abrasive particles are used for cutting materials. This is a cost effective and environmentally friendly technique. Kevlar 49 is one of the most commonly used composite materials and is extensively used in aerospace industries where high strength-to-weight ratio and excellent corrosion resistance are required. This material can be processed by only by abrasive waterjet machining technology due to its high strength. The quality of AWJM is depending upon the process parameters of this technology. This paper provides an experimental investigation for the performance analysis of process parameters on machining Kevlar 49 using abrasive waterjet technology. In this paper mathematical model is also being developed to predict the surface roughness to find the relation between the inputs and the outputs. The first part predicts the surface roughness based on the pressure and the traverse speed whereas the second part indicates the surface roughness variation with standoff distance and the mass flow rate. The model is developed with the back-propagation algorithm using artificial neural network (ANN). The initial weights are assumed, and the algorithm predict and update the weights until it could predict the actual value. The final model is used to verify the results and is found that it is more than 95% accurate. Hence this model is used to study surface roughness by varying all the parameters theoretically.

Elsevier: Materials Today, 2020

Present study deals with hot forging behavior of the sintered AISI 8740 powder metallurgy steels ... more Present study deals with hot forging behavior of the sintered AISI 8740 powder metallurgy steels through powder metallurgy route. These steels extensively used for automobile application for its strength and elongation. Green compacts were fabricated with aspect ratios 1.28, 0.92 and 0.55. These green compacts were fabricated using appropriate die set assembly with 0.6 MN capacity Universal testing machine at 550 ± 10 MPa pressure and subsequently sintered at an elevated temperature in a protective atmosphere using Muffle furnace. Green compacts were forged and analysed with different densification and properties evaluation. Structure property correlation were analysed systematically. The fractography of all compacts show fine dimples and cleavage kind of fracture that confirms mixed mode of fracture due to the existence of multi-phase combination of different alloying elements.

Elsevier Materials Today: Proceedings, 2020

This study shows the vibration and low velocity impact behaviour of AlMg4.5Mn reinforced nanoclay... more This study shows the vibration and low velocity impact behaviour of AlMg4.5Mn reinforced nanoclay nanocomposites at room temperature. Composite samples with different weight percentage of nanoclay were fabricated using liquid state synthesis casting technique, to achieve homogeneous dispersion of Nanoclay. The material characterization was studied by Scanning Electron Microscope (SEM) and Energy-dispersive X-ray spectroscopy (EDS). From the study it was concluded that the Hardness value of the aluminium alloy reinforced nanoclay was increased in addition of nanoclay weight percentage. The natural frequencies of impacted AlMg4.5Mn reinforced nanoclay composites was found to be increased in addition of 2.5 wt% nanoclay.

Elsevier Materials Today: Proceedings, 2020

Ti-6Al-4V is classified among the most commonly used Ti-alloys and is extensively used in aerospa... more Ti-6Al-4V is classified among the most commonly used Ti-alloys and is extensively used in aerospace and medical industries where low-density, high strength and outstanding corrosion resistance are required.
This material cannot be processed by conventional machining methods because of its high strength. Abrasive Waterjet Machining, abbreviated as AWJM, is an unconventional machining process suitable for machining Ti-6Al-4V as it generates less heat affected zone. The quality of AWJM is governed by process parameters, the selection of these parameters is critical in this technology to achieve the desirable output measures. This paper provides an experimental investigation for the performance analysis of process parameters on machining Ti-6Al-4V using abrasive waterjet technology. In order to select appropriate parameters, a mathematical equations were developed using Regression Investigation Method (RIM) Artificial Neural Network (ANN) procedures. Based on the input and output data collected from the experiments, modelling is done and tested for the different set of data to ensure the accuracy. These mathematical models can be used to identify the static and dynamic behavior of the process. These models will further help in simulating the process, expanding the design facilities and studying the physical and chemical variation in the process. Models provide understanding the operations, control methods and the possible optimization. The developed models also help in documenting the performance of the existing system.

Elsevier Materials Today: Proceedings, 2019

Abrasive waterjet machining (AWJM) is one of the unconventional machining practices and is used w... more Abrasive waterjet machining (AWJM) is one of the unconventional machining practices and is used widely in industries. The key output performance measures in this technique are depth of cut and surface roughness. This paper presents the experimental investigation on machining conditions of abrasive waterjet process in machining mild steel. Taguchi's method of design of experiments was used to select input process parameters by varying water pressure, traverse speed, abrasive mass flow rate and standoff distance. The depth of cut and surface roughness were measured using Sigma Scope 500 profile projector and surface roughness tester respectively. After getting the required data from the experimental setup the same data is fed to the artificial neural networks and back propagation algorithm procedure is used to train the data using MATLAB programming package. It is observed that the artificial neural network (ANN) model was able to foresee the new set of data. This mathematical modelling tool can be used to predict dynamic varying different types of input to identify the stability of the system.

Elsevier Materials Today: Proceedings, 2019

The present study deliberates the optical properties of vacuum evaporated Pb 15 Se 85Àx Ge x (x =... more The present study deliberates the optical properties of vacuum evaporated Pb 15 Se 85Àx Ge x (x = 0, 3, 6 at. %) thin films. The absence of sharp peaks in XRD hints about the non-crystalline nature. Transmission spectra (at normal incidence) are acquired in the spectral region of 400-2400 nm. A blue-shift in the transmission spectra hints about the increase in the band-gap. Experimentally, the band-gap is calculated using Tauc-extrapolation method. The band-gap transition is indirect and is found to increase with the substitution of Se by Ge in the glassy alloy. The optical density and penetration depth are calculated using the absorption coefficient data. The penetration depth increases with the increase in Ge-content and the cutoff wavelength shows a blue shift. The obtained optical properties are correlated with the physical parameters. Considering the topological model, it is revealed that the system shows a transition from floppy to the intermediate region. Lone pair electron value is greater than 3 and that favours the glass formation. The distribution of bonds in the present system is also examined using chemical bond approach (CBA) model and the system's cohesive energy (CE) is also calculated. The increase in cohesive energy shows that the average stabilisation energy of the system is increasing. This also reflects the increased value of experimentally calculated optical band-gap. The average heat of atomization also shows an increase with Ge addition. Conduction band potential seems to shift away from the Fermi level. The results are discussed based on the change in bond energy, bond length, total system energy and topo-logical models applied on the system.

Springer Nature Singapore (Internet of Things and Analytics for Agriculture, Volume 2, Studies in Big Data 67), 2019

This paper discusses key challenges faced by transformation of smart cities and integration of gr... more This paper discusses key challenges faced by transformation of smart
cities and integration of green technologies, initiatives, and existing systems that are in place to solve for these challenges. With overpopulation, fast urbanization, and environmental changes, powerful administration of trees and plants is required like never before. We present an Internet of things (IoT)-based smart tree management
architecture for cities which is able to track various characteristics of a given tree such as the air quality, sunlight level, sound pollution level, and other important characteristics for efficient city planning, afforestation plans, and higher quality produce. We divide the solution into three sections: The Sensor Node, The Cloud Integration, and User Experience. We have developed a working prototype using a Raspberry Pi and a mobile application consisting of an intuitive user interface that lets users and farm owners get information about a certain tree and view its information and alerts. We utilize low-power wide-area network modules for the connectivity of the various sensors to the cloud. A map view is also developed which consists of various filters that let city authorities understand the distribution of healthy and damaged trees across the city accompanied by an extensive customized dashboard. A prototype of a
green smart tree management system based on the Internet of things is discussed and implemented. The paper describes the functions and actual characteristics of each system component in detail. The experimental results suggest the feasibility of the application to enable the development of smart cities across theworldwhich will play a key role in decreasing pollution levels across the city and increasing afforestation in areas that require it the most. This solution can be useful in spreading awareness among citizens on the importance of afforestation and proper management of trees in the city and can help farmers in rural areas to avoid hours of manual inspection and labor spent in inspecting the health of their farms.

IOP Journal of Physics: Conference Series, 2019

Abrasive waterjet cutting is one of the unconventional methods used to cut some of the difficult ... more Abrasive waterjet cutting is one of the unconventional methods used to cut some of the difficult to cut materials. In certain materials this method has proved to give better results compared to the conventional methods. In this model the water jet cutting is done on hastelloy using the three parameters which are abrasive mass flow rate, traverse speed, and the stand-off distance. The mathematical modelling to predict the kerf width based on these three input parameters is discussed in this paper. As the relation between the input and the output parameter is non-linear in nature neural network back propagation algorithm is used for the prediction. Here the experiment is conducted using waterjet cutting machine and the data's like surface roughness, metal removal rate, kerf width and the kerf angle data are collected. Both the input and the output parameters are fed to the neural network toolbox programmed in the MATLAB. After 1000 iterations it has been found that the prediction is closer to the actual value. The mathematical constants which is the weight matrix is used to test the new set of data for accuracy. It has been found that the prediction is more accurate compared to the conventional methods. This experiment is based Taguch's design which uses the above three parameters to cut the material. This paper also discusses on the predication of surface roughness of hastelloy created due to the variation in these parameters.

International Journal of Recent Technology and Engineering (IJRTE), 2019

Abrasive waterjet cutting is one of the unconventional cutting processes capable of cutting exten... more Abrasive waterjet cutting is one of the unconventional cutting processes capable of cutting extensive range of difficult-to-cut materials. This paper assesses the impact of process parameters on surface roughness which is a significant machining performance measure in abrasive waterjet cutting of hastelloy. The experimental parameters were selected based on Taguch's design of experiments. Experiments were conducted in varying nozzle traverse speed, abrasive mass flow rate and standoff distance for cutting hastelloy using abrasive waterjet cutting process. The effects of these parameters on surface roughness have been discussed.

Self-healing materials are artificial or synthetically created substances that have the built-in ... more Self-healing materials are artificial or synthetically created substances that have the built-in ability to automatically repair damage to themselves without any external diagnosis of the problem or human intervention. This article presents the current research and developments in self-healing composite materials. A detailed study is conducted on various types of self-healing composites with their self-healing mechanisms. The applications of self-healing materials in various fields including space sector is also discussed. Economics and Future outlooks for self-healing smart materials is highlighted at the end of the article. This research article will be useful to manufacturers, policy makers and researchers widely.

Key Words: Self-Recuperating Structures; Ionomeric Self-Healing; Anticorrosion Coating; Fatigue Resistance; Surface Cracks; Intrinsic and Extrinsic Self-Healing

The three dimensional spacer textures, comprise of two bi-directional woven texture surfaces, whi... more The three dimensional spacer textures, comprise of two bi-directional woven texture surfaces, which are mechanically associated with vertical sewed heaps. The three dimensional spacer textures can be made of glass fiber, carbon fiber or basalt fiber. The Three Dimensional Composites are classified based on the different factors depending on the orientation of the yarn, the yarn sets and the geometry. The three dimensional composites have multiple layers and hence they overcome delamination, which is a common defect in two dimensional composites. Nevertheless, these composite materials have relatively lower transverse properties and also, have size and thickness limitations. This literature reviews on several important published literatures on three dimensional composite materials. The review studies the numerous effects that lead to the failure of the composite material.

International Journal of Scientific & Engineering Research, 2017

The increasing availability of green power enables electricity customers to accelerate installati... more The increasing availability of green power enables electricity customers to accelerate installation of renewable energy technologies. This review paper provides various approaches towards power market worldwide. Impact of power generation on international trade are discussed to understand various opportunities in green power generation. Current trends used in green power generation with scope for future advancements are also discussed in detail. Also the various challenges in this field with economic and ecological effects are addressed. This review paper will help researchers and policy makers widely.

Index Terms— Green Power, wind energy, solar energy, sustainability, renewable energy, international trade