David Christopher

Wolaita Sodo University

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P. Rajesh Kanna

Vellore Institute of Technology University

S. Joe Patrick Gnanaraj

Kalasalingam Academy of Research and Education

Asiful H. Seikh

King Saud University

Hussein A. Mohammed

King Fahd University of Petroleum and Minerals

Moti Lal Rinawa

Government Medical College

G. R. Madhusudhana

Indian Institute of Science Bangalore

Md Ataul Islam

University of Manchester

P. Venkumar

Kalasalingam Academy of Research and Education

Mohamad Reda A. Refaai

Prince Sattam Bin Abdulaziz University

B. S. Praveen Kumar

Govt. Dental College & Hospital

Cooperative Institutions

King Saud University

Sathyabama Institute of Science and Technology

Saveetha University

Anna University, Chennai

Cracow University of Technology

Indian Institute of Science Bangalore

Institute of Engineering

Velammal Medical College Hospital and Research Institute

Princess Nourah bint Abdulrahman University

Aditya Birla (India)

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Thermal Storage for the Analysis of Hybrid Energy Systems Based on Geothermal and Solar Power

International Journal of Photoenergy (2022)

K. U. Aravind Muthu Mekala Natarajan N. P. Muthuraju Nidhi Soni Essam A. Al‐Ammar

Thermal degradation of geothermal energy occurs even during the duration of geothermal energy facilities. The enormity and efficiency of thermal energy available for electric transformation, as well as plant performance and power production, are both affected by the decrease in geofluid heat. Additionally, due to the generally increased turbine exhaust temperatures, the efficiency of geothermal energy based upon air-cooled organic Rankine cycle devices (ORCs) degrades considerably at hot room temperatures. A newly designed Geothermal-Concentrator Solar Power (GEO-CSP) station is simulated in this work, which allows for greater geothermal power use and enhances the effectiveness of the geothermal ORC system over the power plant’s lifespan. The geothermal fluid entering the ORC’s heating element is heated using the sun’s radiation. The CSP facility is fitted with a thermal energy storing unit that stores excess energy from the sun accessible throughout the day and releases it at nighttime whenever the energy system’s performance is better. When the storage facility is included in the concentrator CSP technology, the incremental yearly energy generation from solar increases by 19 percent, from 5.3 percent to 6.3 percent, similar to the geothermal-only plant. As a result, adding a TES unit to the hybrid unit could be quite beneficial.

Organic Rankine Cycle

Geothermal heating

Geothermal power

Thermal energy

10.1155/2022/1296822

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Citations (2)

Application of IoT-Based Drones in Precision Agriculture for Pest Control

Advances in Materials Science and Engineering (2022)

Mohamad Reda A. Refaai Vinjamuri S. N. C. H. Dattu N. Gireesh Ekta Dixit C.H. Sandeep

Unmanned aerial vehicles (UAVs), commonly known as drones, have been progressively prevalent due to their capability to operate quickly and their vast range of applications in a variety of real-world circumstances. The utilization of UAVs in precision farming has lately gained a lot of attention from the scientific community. This study addresses with the assistance of drones in the precision agricultural area. This paper makes significant contributions by analyzing communication protocols and applying them to the challenge of commanding a fleet of drones to protect crops from parasite infestations. In this research, the effectiveness of nine powerful deep neural network models is measured for the detection of plant diseases using diverse methodologies. These deep neural networks are adapted to the immediate situation using transfer learning and deep extraction of features approaches. The presented study takes into account the used pretrained deep learning model for extracting features and fine-tuning. The deep feature extraction characteristics are subsequently categorized using support vector machines (SVMs) and extreme learning machines (ELMs). For measuring performance, the precision, sensitivities, specific, and F1-score are all evaluated. Deep feature extraction and SVM/ELM classification generated better outcomes than transfer learning, according to the analysis result. Furthermore, the analysis of the various methodologies tries to assess their effectiveness and costs. The different approaches, for example, confront difficulties such as investigating the region in the shortest possible time feasible, while eliminating the same region being searched by more drones, detecting parasites, and stopping their spread by applying the appropriate number of pesticides. Simulation models are a significant aid to researchers in conducting to evaluate these technologies and creating specific tactics and coordinating procedures capable of effectively supporting farms and achieving the aim. The main objective of this paper is to compare the search techniques of two distinct methods of parasitic to identify performance.

Drone

Transfer of learning

Precision Agriculture

Feature (linguistics)

10.1155/2022/1160258

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Citations (10)

Employing a Carbon-Based Nanocomposite as a Diffusive Solid-Phase Extraction Adsorbent for Methamphetamine for Therapeutic Purposes

Adsorption Science & Technology (2023)

K. Lakshmi Kala G. Anbuchezhiyan Kavitha . Pingili Pradeep Kumar Singh V. M. Vel

Due to the obvious minimal doses of drugs in biological matrices as well as the societal difficulties caused by methamphetamine usage, methamphetamine identification is critical in clinical and forensic laboratories. Because of their simple and inexpensive production procedure, as well as their excellent selectivity and sensitivity, polymeric carbon-based nanocomposites are strong contenders for the diffusive solid-phase extraction approach. The diffusive solid-phase extraction absorbent nanographene oxide polypyrrole composite was produced and used to recover methamphetamine from a complicated urine substrate. The generated NGPPC was fully characterized, and the significant extracting parameters have been explored using the one-parameter-at-a-time strategy. NGOPC is being used to extract methamphetamine using a urine medium with high efficiency. The NGPPC synthesizing procedure was easy, and the extraction method will demonstrate good repeatability. Moreover, the practical and efficient synthesis process stimulates the use of carbon-based compounds in various extraction procedures. As for detecting and quantifying equipment, HPLC monitors are being used. 300 mL methanol, 7 min extracting and desorption duration, 5000 mixing frequency, urinary pH value of 20, 40 mg adsorption, and 5 mL amount of urine were the optimal extraction variables. Following tracing the calibration graph, the method’s linear ranges were determined to be 40-600 ng/ml. The detection limits (LOD) and quantitation limits (LOQ), correspondingly, were 10 and 35.80 ng/mL. The proposed methodology seemed to have a detection range of 9 ng/mL. The suggested approach’s applicability in numerous characterization and medical facilities was proven by the examination of addicted subjects using the proposed technique. For successful extraction of methamphetamine using biological urine samples, the carbon-based adsorbent was being used as diffusive solid-phase extraction adsorption.

Solid phase extraction

Repeatability

10.1155/2023/8650678

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Citations (1)

EXPERIMENTAL STUDY OF HIGH MOISTURE CONTENT GAS CROSSFLOW OVER A CYLINDER AT MODERATE REYNOLDS NUMBERS

Journal of Engineering Thermophysics (2001)

David Christopher

Source

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Citations (1)

A Systematic Review on the Mechanical, Tribological, and Corrosion Properties of Al 7075 Metal Matrix Composites Fabricated through Stir Casting Process

Advances in Materials Science and Engineering (2023)

M. Sambathkumar R. Gukendran T. Mohanraj D.K. Karupannasamy N. Natarajan

Aluminium alloy components are used in lightweight engineering applications and lack mechanical properties, wear resistance, and corrosion resistance. When hard reinforcement particulates are dispersed in the aluminium matrix alloy, aluminium matrix composites (AMCs) are formed. This new material exhibits enhanced properties such as better specific stiffness, specific strength, corrosion resistance, elastic modulus, wear resistance, and lightweight. AMCs have many favorable properties compared to their alloy and extensive applications. Especially, in the space industry, where weight reduction and an increase in modulus are prevalent, the strength-to-weight ratio is more important. This study focuses on the tribological, mechanical, and corrosion properties of Al 7075 metal matrix composites (MMCs) reinforced with one or more particulates such as aluminium oxide (Al2O3), boron carbide (B4C), titanium carbide (TiC), silicon carbide (SiC), titanium dioxide (TiO2), and titanium diboride (TiB2). In AMCs, the reinforcements are incorporated by either the solid or liquid metallurgy route. The study addresses the findings and shortcomings in the preparation of MMCs with reinforcements and their improvement in corrosion resistance, wear resistance, mechanical properties, and lower coefficient of thermal expansion than the Al 7075 base alloy. A comprehensive survey of reinforcement particulates in MMCs and their influences are outlined from the literature, encompassing recent research trends to enhance the structural properties.

Specific strength

Boron carbide

Titanium diboride

10.1155/2023/5442809

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Citations (48)

Optimization and Wear Properties for the Composites of Metal Matrix AA8011/Boron Nitride Using Taguchi Method

Journal of Nanomaterials (2022)

B. S. Praveen Kumar K. R. Shobha Manoj Kumar Singh Moti Lal Rinawa S. Madhavarao

In automotive and aircraft design, a new emerging material known as AA8011 metal matrix composite has earned a place for the reason that it is extremely durable and extremely hard. Newer composite variants were created and selected because of the demand for improved tribological performance. This study’s objective is to find out how an AA8011‐Boron Nitride metal matrix composite (MMC) wears out under different loads and sliding speeds. AMMC fortified with Boron Nitride particles are created using the powder metallurgy route and contain weight fractions ranging from 10% to 15% of the AA8011 and 37 μ m Boron Nitride particles. The material is made in an electric melting furnace through a stir casting procedure. Next, the materials are tested to see how long they will last in a tribotester set up like this: a block on a roller. With a controlled experimentation strategy, wear data can be collected using the L27 Taguchi method. Dry sliding wear of composites is controlled by four parameters: Boron Nitride substance, load‐bearing capacity, slid speed, and sliding time. An analysis of variance is used to determine their effects. Sliding speed, friction, and normal load all have an effect on how much dry sliding wear occurs. In addition, the least amount of wear is obtained by combining the four controlling parameters optimally.

Matrix (chemical analysis)

10.1155/2022/6957545

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Citations (14)

TRANSIENT NATURAL CONVECTION HEAT TRANSFER IN A CAVITY FILLED WITH A FLUID-SATURATED, POROUS MEDIUM

Proceeding of International Heat Transfer Conference 9 (1986)

David Christopher

Transient (computer programming)

Transient analysis

10.1615/ihtc8.3850

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Citations (5)

Optimization and Tribological Properties of Hybridized Palm Kernel Shell Ash and Nano Boron Nitride Reinforced Aluminium Matrix Composites

Journal of Nanomaterials (2022)

M. Lokeshwari P. Vidya Sagar K. Dilip Kumar D. Thirupathy Ram Subbiah

The tribological properties of hybridized reinforced aluminium matrix composites were optimized using Taguchi and Grey Relational Analysis in conjunction with an L16 orthogonal array. The combination of palm kernel shell ash (PKSA) (0–5 wt. %) along with nano BN reinforcements was taken in interest. Loads and speeds (500, 750, 1000, and 1250 rpm) were employed as control parameters for the experiment. Using a Taber type abrasion machine, the wear samples were made, and the wear experiments were carried out. Speed and load were more important than the percentage of reinforcements in composites when it came to evaluating wear index and loss of volume. With respect to wear index and volume loss, Taguchi‐relational Grey’s analysis identified A3B1C1 (reinforcement = 5 wt. %; load = 500 g; speed = 500 rpm) as the optimal process parameter combination, with a reinforcement of 3 wt. %, load = 500 g, and speed = 500 rpm being the second‐best option. Validation tests have revealed that the anticipated and experiment values at the optimal situations are both within the acceptable range. Performance is influenced more by speed than by load, which is influenced more by the weight percentage of composites, as demonstrated by the application of the Taguchi and Grey Relational Analysis methods.

Palm kernel

Matrix (chemical analysis)

10.1155/2022/8479012

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Citations (9)

Mechanical Behaviour of Alkali-Treated Fabric-Reinforced Polymer Matrix Composites

Advances in Polymer Technology (2022)

M. D. Mohan Gift Sneha S. Mantri Raviteja Surakasi Moti Lal Rinawa Dhiren Patel

Polyethylene (PE) was used as a composite material to create a fabric containing 40% pineapple, 30% jute, and 30% cotton fibres by weight. The physical characterisation is carried out, like deterioration and water absorption tests. PE-based composites were shown to have a lower water absorption rate when dipped in deionized water to perform an absorption test. Fabric/PE composites decomposed slowly in the soil during the degradation test. Alkali solution of 5 percent, 7 percent, and 9 percent sodium hydroxide by weight for 60 minutes was studied as alkali impact mechanical characteristics: mechanical testing’s like tensile strength and modulus, elongation at break, bending strength, and modulus. Data investigation exposed that the tensile strength and modulus, elongation at break, bending strength, and composite modulus values were 64 MPa and 871 MPa, 23.14 percent, 45 MPa, and 512 MPa. There were tensile strength and modulus, elongation at break, bending strength, and modulus of the neat polyethylene sheet that were 32Mpa and 342 MPa, 79 percent, 22 MPa, and 234 MPa, respectively. Compared to a polyethylene sheet, composite values for tensile strength and modulus, bending strength, and modulus raised by 107%, 156%, 110%, and 115% as a result of fabric reinforcing.

Elongation

Flexural modulus

Sodium hydroxide

Tensile testing

10.1155/2022/1833955

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Citations (1)

NATURAL CONVECTION MELTING AROUND A HORIZONTAL CYLINDER BURIED IN FROZEN WATER-SATURATED POROUS MEDIA

Proceeding of International Heat Transfer Conference 9 (1994)

David Christopher Bu‐Xuan Wang

10.1615/ihtc10.1540

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Citations (6)