Open Access Original Research Article

Studies of A356 Aluminum Alloy for Sand Mould Casting Gating System

Kishor Purushottam Kolhe, Abebe Halefom Gebrekidan

Journal of Engineering Research and Reports, Page 1-13
DOI: 10.9734/jerr/2022/v22i917558

The present study focus on tackling the casting defect of aluminium A356 alloy, this alloys have very good casting and machining characteristics, which dominantly affects the part produced by identifying the major defects caused by existing gating system. The major objective of this study is to minimize casting defect of spare part manufactured in textile Share Company by using Pro CAST software. This study is conducted in Bahirdar textile foundry workshop, the casting parameters which highly contributes to the soundness casting are identified with basic metallurgical and foundry properties of aluminium A356 alloy. The development of gating system for aluminium alloy is done by following American foundry society standard for getting reliable results. The optimization of Ingate and riser of gating system is carried out by Taguchi Method. The analysis result reports the shrinkage (macro) porosities and hot spot defects under existing gating system practised in the factory. After identifying the porosity defect; results of analysis process are iterated to get the optimum results, porosity found to be minimized for various gating system parameters. From simulation result; it is found that the best suited gating system parameter for aluminium A356 alloy sand casting is tapered sprue in decreasing initiation of defect from scratch. Finally, it is recommended that the company should implement the optimized processes parameters in addition to taking remedial action on the influential factors of the casting process.

Open Access Original Research Article

Characterization of Monostatic Radar System for Accuracy Improvement through Parameter Estimation

K. I. C. Ugwu, J. Eke, D. O. Abonyi

Journal of Engineering Research and Reports, Page 14-21
DOI: 10.9734/jerr/2022/v22i917560

This paper presents the characteristics of monostatic radar for improving accuracy of detection through determination of the factors that were responsible for power losses in radar signal transmission and interception by targets. These factors were improved upon by looking at some parameter like the antennae gain or transmitter gain, and evaluating the result through Matlab testing of some measured distance values. This was achieved by simulating mathematical radar equations by liu, 2014, of signals transmitted over selected distances say, from 5km to 100km and evaluated the result. These power losses in the transmitted signal which characterize the error in range resolution and target detection of the returned signal in a radar system, were mitigated by increasing the antennae or transmitter gain over long distances in monostatic radar to improve the range and detection capability. The transmitting material effective aperture which forms part of the radar design was also characterized to show its effect in high definition radar development. In the table below, results of matlab simulation of varied target positions were tabulated to show better definition of target ranges over long distances while increasing transmitter gain, and effective aperture of the transmitting material though it was a function of the distance of the receiver from the target. Specific radar design and implementation are basically worked upon through these factors which can aid material selection to forestall errors in radar target detection.

Open Access Original Research Article

An Enhanced Intelligent Facts Device for Reduction of Losses on Power Lines

K. I. Anyanor, M. U. Efoke, J. P. I. Iloh

Journal of Engineering Research and Reports, Page 22-33
DOI: 10.9734/jerr/2022/v22i917561

In this research, an enhanced intelligent FACTS device for reduction of losses on power lines using intelligent Static Synchronous Series Compensator (SSSC) devices for Nigerian 330kv network has been presented. The findings showed total real power losses of 127.9131MW before network compensation, with transmission lines accounting for 125.7MW and producing stations accounting for 2.2131MW. After compensation using Static Synchronous Series Compensator (SSSC), the total Real power losses were reduces to 104.53MW, while the total Reactive losses (MVar) reduced to 26.87MVar. The research concludes that the injection of reactive power by Static Synchronous Series Compensator (SSSC) devices compensates for the drop in voltage, leading to improvement in voltage and reduces power losses for the network.

Open Access Original Research Article

Radio Wave Propagation in a Forested Channel

A. S. Adegoke, U. K. Okpeki, O. Green

Journal of Engineering Research and Reports, Page 34-40
DOI: 10.9734/jerr/2022/v22i917562

The appearance of vegetation along radio communication channel can significantly reduce quality of propagating signal. Hence, the need for wireless signal operators to understand the characteristic of channel components for effective radio planning and deployment.

This paper has investigated the influence of vegetative channel on wireless signals and examined the dependence of signal loss on path geometry. Measurements were conducted in a sort-depth forest (at SHF frequencies) following two different paths (paths 1 & 2) within the woodland. The experimentation was conducted in autumn and summer so as to determine likely seasonal effect on losses along different path geometries.

Results show decay in signal level as the depth of penetration increases which also varies from path to path. These (results) were later compared with standard empirical models MED, FITUR and COST 235 and it shows a statistical adherence with only one of the models, the MED.

It is therefore imperative that for effective signal deployment devoid of significant impairment, wireless network operators must take cognisance of the channel characteristics and path geometries in order to guarantee proper planning, modeling and deployment.

Open Access Original Research Article

Deep Neural Network Approach Based Segmentation, Detection and Classification of Brain Tumor

Asim Zaman, Ling Yu, Nasir Ud Din, Kifayat Ullah, Qaisar Hayat

Journal of Engineering Research and Reports, Page 41-50
DOI: 10.9734/jerr/2022/v22i917563

The segmentation, detection and extraction of malignant tumor regions from magnetic resonance (MR) images are challenging tasks in medical image analysis. Approaches based on machine and deep learning have been introduced, which performed better than traditional image processing methods. However, many approaches still show limited ability due to the complex dataset and image modalities. This study evaluated the deep learning approach's performance and traditional image processing algorithms for medical imaging segmentation, detection, and classification. The proposed system comprises multiple stages. The Median filters are used in the pre-processing step, and morphological operation and Otsu thresholding are used to segment MR images. Discrete Wavelet Transform (DWT) algorithm is considered in the extraction features, and their classification is executed by a convolutional neural network (CNN) and support vector machine (SVM) algorithms. The Mat lab has been used for simulation and experimental findings to evaluate the suggested method's performance on the brain's complex and highly 2D structures. The results show that the methodology is reliable and efficient, with 93.5% accuracy.

Open Access Original Research Article

Challenges in Hybrid Teaching Amidst Pandemic: The Proposed Model

Jimmy Nebrida, Aldrin Bangud

Journal of Engineering Research and Reports, Page 51-64
DOI: 10.9734/jerr/2022/v22i917564

This study aimed to understand how an engineering division transforms its practices to attune to hybrid teaching pedagogy in higher education. Specifically, it aimed to identify challenges encountered by lecturers and students and how these challenges are responded to. Furthermore, it was aimed to develop a model to address problems in hybrid teaching. The study made use of a qualitative research design to gather in-depth insights about the problem and generate new ideas for research. Theoretical sampling is used as prescribed for grounded theory. It identifies the participants which allows a theory to emerge and supports the conducting of interviews with an initial interview from the head of division until saturation is achieved. Results of the study showed that the engineering division recognized the challenges brought by hybrid teaching like unequal opportunity among students to be engaged in class activities, inefficient support for online students, technical issues with the platform, lack of devices for online learning, additional time during the weekend, unresponsive online students, inability to monitor online students, low level of readiness and hesitation among lecturers, unstable internet connection and sound-related issues. The division responded with solutions like provision of laptops, collaborative teaching, online teaching apps, gamification, audio-visual learning, tutorial videos, use of school and personal resources, and repetition for mastery. The mechanism utilized in addressing the challenges faced are continuous professional development, informal sharing and discussion with colleagues, and institutional in-house training.

Open Access Original Research Article

Investigative Study of Effects of Gallus domesticus guano, Cucumeropsis mannii shell and Elaeis guineensis shell Additives on the Refractory Properties of Isiagu Clay

Victor E. Ojukwu, Philomena K. Igbokwe, Victor I. Ugonabo

Journal of Engineering Research and Reports, Page 65-75
DOI: 10.9734/jerr/2022/v22i917565

This research investigated the effects of chicken dropping, melon shell and palm kernel additives on the refractory properties of Isiagu Clay. The raw materials were collected locally, processed and analysed using Scanning Electron Microscope/Energy Dispersive X-ray (SEM/EDX). The additives were added to the raw clay in the ratio of 2.5,5.0,7.5 and 10 wt% and fired at 900oC and 1100oC, respectively. The refractory properties measured were; linear shrinkage, apparent porosity and bulk density. The result of the SEM/EDX analyses showed that the clay is a fireclay since it contains 61.68% Al2O3 and 34.97% SiO2 while chicken dropping, melon shell, and palm kernel shell contained 37.41% SiO2, 84.62% P2O5, and 48.31% Nb2O5, respectively. Chicken dropping was responsible for strength, melon for toughness and palm kernel shell for conductivity. SEM/EDX morphological results showed that the clay sample contains tiny to coarse particles. The bulk density measurement confirmed the strength and toughness of melon shell, the only additive which met the international standard for refractory application. XRD analysis results showed the presence of two crystalline phases at 21.4o and 22.4o namely, quartz and calcite in the additives used which are both responsible for strength in the refractory brick. Sudden variation in properties was observed for chicken droppings due to the presence of a reasonable amount of P2O5. From the study, melon shell and palm kernel shell are suitable for refractory brick production and further studies are recommended for chicken dropping. ANOVA results confirmed that for melon shell and apparent porosity only temperature was significant.

Open Access Original Research Article

Fuzzy Equalization Strategy Based on Multilayer Circuits

Xu Lu, Chong Wang

Journal of Engineering Research and Reports, Page 76-88
DOI: 10.9734/jerr/2022/v22i917566

In this study, the influence of the external current and the equalization current on the working current of the lithium battery during the equalization process is fully analyzed, a fuzzy equalization approach based on a multilayer circuit is proposed, with external current and the battery's SOC as inputs, and fuzzy rules to output a suitable equalization current to keep the battery's operating current within the permitted range. It is verified by simulation that the proposed fuzzy control strategy can limit the operating current of the lithium battery within the range of [-3A-3A], and the maximum operating current of the battery is reduced by 50% compared with the unbalanced strategy. It can ensure the safety in the process of battery balancing.