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Assessment Of The Extent Of Implementation Of Quality Management System (Qms) And Cost Of Quality (Coq) Concepts – A Case From A Developing Country, M.B. Ramzan, S.M. Qureshi, M. Ullah, M.S. Memon, M.A. Siddiqui Apr 2025

Assessment Of The Extent Of Implementation Of Quality Management System (Qms) And Cost Of Quality (Coq) Concepts – A Case From A Developing Country, M.B. Ramzan, S.M. Qureshi, M. Ullah, M.S. Memon, M.A. Siddiqui

The Journal of Engineering Research

In developed countries, the application of the quality management system (QMS) is widely proven. However, in developing countries, like Pakistan, industries are not mature enough to understand and implement the system. The aim of this study is to examine the perception of quality, implementation of QMS and cost of quality (COQ) program in value-added garment sector, which is one of the major subsectors of textile industry in Pakistan. The methodology of the study is a questionnaire survey. The findings suggest that the majority of the respondent firms have well implemented quality management (QM) practices. Trend of results also depicts that …

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Investigation Of Effective Parameters Of Drop-On-Demand Droplet Generator, Mojtaba Ghodsi, M. Ghodsi, Y. Hojjat, H. Sadeghian, H. Ziaiefar, M. Mohammadzaheri, A. Al-Yahmedi Apr 2025

Investigation Of Effective Parameters Of Drop-On-Demand Droplet Generator, Mojtaba Ghodsi, M. Ghodsi, Y. Hojjat, H. Sadeghian, H. Ziaiefar, M. Mohammadzaheri, A. Al-Yahmedi

The Journal of Engineering Research

This article presents a design and development of a drop-on-demand (DOD) droplets generator. This generator uses molten metal as a liquid and can be used in fabrication, prototyping and any kind of printing with solder droplets. This setup consists of a vibrator solenoid with tunable frequency to produce a semi-spherical shape of molten metal, close to the surface of fabrication. This design also has a nozzle with micro-size orifice, a rod for transmitting force and a heater to melt the metal and keep it in superheat temperature. This DOD can produce droplets in different sizes (less than 550 µm) by …

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An Enhanced Smith Predictor Based Control System Using Feedback-Feedforward Structure For Time-Delay Processes, M. Mohammadzaheri, R. Tafreshi Apr 2025

An Enhanced Smith Predictor Based Control System Using Feedback-Feedforward Structure For Time-Delay Processes, M. Mohammadzaheri, R. Tafreshi

The Journal of Engineering Research

This paper presents enhanced Smith predictor based control systems (SPBCSs) for processes with a time-varying or fixed time delay. This work focuses on improving the arrangement and asynchrony of SPBCS components rather than the design of the predictor and the feedback controller, which have been well discussed in the literature. The proposed control system advances SPBCS through implementation of two design recommendations: (i) replacing the classical feedback controller by a feedback-feedforward control system, and (ii) synchronizing the reference signal and the predicted output. As a result, common shortcomings of SPBCSs or control systems based on Pade approximation, i.e. the …

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Newtonian And Non-Newtonian Pulsatile Flows Through An Artery With Stenosis, Abdus Samad, A. Husain, M. Zunaid, A. Samad Apr 2025

Newtonian And Non-Newtonian Pulsatile Flows Through An Artery With Stenosis, Abdus Samad, A. Husain, M. Zunaid, A. Samad

The Journal of Engineering Research

The current study presents three-dimensional modeling and analysis of blood flow through artery stenosis under several variants of pulsatile flow to mimic the atherosclerosis artery disease. The study considered Newtonian and non-Newtonian blood flow models and solved the three-dimensional laminar and unsteady Navier-Stokes (NS) equations for different inlet velocity profiles. The Carreau Yasuda model was used for hemodynamics modeling of fluid viscosity. A comparative analysis was carried out for Newtonian and non-Newtonian fluid models under several simple pulsatile, equivalent pulsatile and physiological velocity profiles. The non-Newtonian fluid exhibited a higher centerline velocity. Wall shear stresses, shear strain rates, velocity fields, …

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Design Of Biomechanical Legs With A Passive Toe Joint For Enhanced Human-Like Walking, Riadh Zaier, A. Al-Yahmedi Apr 2025

Design Of Biomechanical Legs With A Passive Toe Joint For Enhanced Human-Like Walking, Riadh Zaier, A. Al-Yahmedi

The Journal of Engineering Research

This paper presents the design procedure of a biomechanical leg, with a passive toe joint, which is capable of mimicking the human walking. This leg has to provide the major features of human gait in the motion trajectories of the hip, knee, ankle, and toe joints. Focus was given to the approach of designing the passive toe joint of the biomechanical leg in its role and effectiveness in performing human like motion. This study was inspired by experimental and theoretical studies in the fields of biomechanics and robotics. Very light materials were mainly used in the design process. Aluminum and …

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Estimating Drilling Cost And Duration Using Copulas Dependencies Models, M. Al Kindi, M. Al-Lawati, N. Al-Azri Apr 2025

Estimating Drilling Cost And Duration Using Copulas Dependencies Models, M. Al Kindi, M. Al-Lawati, N. Al-Azri

The Journal of Engineering Research

Estimation of drilling budget and duration is a high-level challenge for oil and gas industry. This is due to the many uncertain activities in the drilling procedure such as material prices, overhead cost, inflation, oil prices, well type, and depth of drilling. Therefore, it is essential to consider all these uncertain variables and the nature of relationships between them. This eventually leads into the minimization of the level of uncertainty and yet makes a "good" estimation points for budget and duration given the well type. In this paper, the copula probability theory is used in order to model the dependencies …

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Out Of Axis Movement Of An Auv Inside A Water Pipeline, M. Moonesun, A. Mahdian, Y.M. Korol, A. Brazhko Apr 2025

Out Of Axis Movement Of An Auv Inside A Water Pipeline, M. Moonesun, A. Mahdian, Y.M. Korol, A. Brazhko

The Journal of Engineering Research

The research intends to evaluate the variation in the resistance and the lift of a torpedo shaped AUV brought about by the wall effect inside the pipe as it moves out of the axis inside a water pipeline. Movement of an AUV at the axis of a pipe causes minimum resistance and lift forces, but when the AUV moves at a position parallel with the axis of the pipe (out of axis of the pipe), the hydrodynamic forces especially the lift force changes. The AUV must be able to move a float inside the pipe and perform non-contact inspection. In …

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Quantitative Analysis Of Force And Torque In Bone Drilling, K. Alam, R. Muhammad, A. Shamsuzzoha, A. Alyahmadi, N. Ahmed Apr 2025

Quantitative Analysis Of Force And Torque In Bone Drilling, K. Alam, R. Muhammad, A. Shamsuzzoha, A. Alyahmadi, N. Ahmed

The Journal of Engineering Research

Bone drilling is an important and the most frequent operation in orthopaedics and other bone surgical procedures. Prediction and control of drilling force and torque are critical to safe and efficient surgeries. This paper studies the drilling force and torque arising from bone drilling process. Drilling parameters such as drilling speed, feed rate, drill size and drill condition (sharp and worn) were changed to measure the force and torque in the direction of the drill penetration. Experimental results demonstrated lower drilling force using a sharp drill compared to a worn drill for similar drilling conditions. Contrary to the drilling force, …

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Strengthening Of Historical Stone Masonry Buildings In Oman Using Textile Reinforced Mortars, A.H. Al-Saidy, A.W. Hago, S. El-Gamal, M. Dawood Apr 2025

Strengthening Of Historical Stone Masonry Buildings In Oman Using Textile Reinforced Mortars, A.H. Al-Saidy, A.W. Hago, S. El-Gamal, M. Dawood

The Journal of Engineering Research

Most historical buildings and structures in Oman were built using unreinforced stone masonry. Such structures are prone to damage from seismic activity as these structures have negligible resistance to tensile stresses. This paper presents an exploration of the physical and chemical properties of local building materials and the results of experiments with a new strengthening technique using textile reinforced mortar. Limestone and Sarooj were the main building materials used historically in these buildings. Sarooj is a local Omani term for artificial pozzolana produced by calcining clays. Two mortar mixes were developed, one as the jointing mortar and the second as …

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Development Of A System Model For Determining Optimal Personnel Interaction Strategy In A Production Industry, B. Kareem, A. Adekiigbe Apr 2025

Development Of A System Model For Determining Optimal Personnel Interaction Strategy In A Production Industry, B. Kareem, A. Adekiigbe

The Journal of Engineering Research

Manufacturing organizations have become more complex in recent time as a result of technological advances. Communication among production workers operating in an environment marked by increased organizational complexity may require planning for the economically appropriate selection of network channels/media with enhanced productivity. This paper examines traditional and modern communication channels (media) and their comparative advantages over one another in their adoption in manufacturing organizations. In this framework, six media (human messengers, mobile-phones, intranet, fixed-internet, mobile-internet, and private branch exchange [PBX] phone systems) were subjected to analyses using five identified network patterns (all-channel, chain, Y, wheel, and circle) of interactions in …

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Storage Of Nitrous Oxide (Nox) In Diesel Engine Exhaust Gas Using Alumina-Based Catalysts: Preparation, Characterization, And Testing, A. Alsobaai Apr 2025

Storage Of Nitrous Oxide (Nox) In Diesel Engine Exhaust Gas Using Alumina-Based Catalysts: Preparation, Characterization, And Testing, A. Alsobaai

The Journal of Engineering Research

This work investigated the nitrous oxide (NOx) storage process using alumina-based catalysts (K2 O/Al2 O3 , CaO/Al2 O3, and BaO/Al2 O3 ). The feed was a synthetic exhaust gas containing 1,000 ppm of nitrogen monoxide (NO), 1,000 ppm i-C4 H10 , and an 8% O2 and N2 balance. The catalyst was carried out at temperatures between 250–450°C and a contact time of 20 minutes. It was found that NOx was effectively adsorbed in the presence of oxygen. The NOx storage capacity of K2 O/Al2 O3 was higher than that of BaO/Al2 O3. The NOx storage capacity for K2 O/Al2 O3 …

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Mathematical Model Describes Treatment Of Waste Water Using Modified Activated Carbon, A.S. Ibrahim, A.S. Al Buloshi, S.S. Al Zaabi, L.A. Al Yafai Apr 2025

Mathematical Model Describes Treatment Of Waste Water Using Modified Activated Carbon, A.S. Ibrahim, A.S. Al Buloshi, S.S. Al Zaabi, L.A. Al Yafai

The Journal of Engineering Research

The proposed mathematical model covered in this paper includes the most important parameters associated with the rates of adsorption and desorption. Also, partial pressure is included since it is an important factor that affects rates of adsorption and desorption. The study focuses on the effects of the constant rates on adsorption of pollutant concentrations for benzene, nickel, cadmium, and copper using modified active carbon. When the rate constant of adsorption decreases, the pollutant concentration will also decrease, yielding high acceptable evidence of the logic of the proposed mathematical model. Also, the proposed model is compared with experimental data and other …

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A Comparative Study On Energy Derived From Biomass, A.M. Algarny, I.M. Al-Naimi, M.A.M Alhefnawy Apr 2025

A Comparative Study On Energy Derived From Biomass, A.M. Algarny, I.M. Al-Naimi, M.A.M Alhefnawy

The Journal of Engineering Research

The paper promotes sustainable community through empowering the production and utilization of biomass renewable energy. The aim of this paper is to urge societies to adopt sustainable energy practices and resources; the objective is to appraise the possibilities of biomass energy produced through a neighborhood in Eastern Province, Saudi Arabia. The system incorporates an evaluation of the measure of biomass created, then utilizes two ascertaining techniques to gauge whether the measure of energy can be delivered. The computation strategies are hypothetical, with one drawn from past works and the other from a Biomass Calculation Template performed as part of the …

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Performance Comparison Of Digital Circuits Using Subthreshold Leakage Power Reduction Techniques, B. Kalagadda, N. Muthyala, K.K. Korlapati Apr 2025

Performance Comparison Of Digital Circuits Using Subthreshold Leakage Power Reduction Techniques, B. Kalagadda, N. Muthyala, K.K. Korlapati

The Journal of Engineering Research

Complementary metal-oxide semiconductors (CMOS), stack, sleep and sleepy keeper techniques are used to control sub-threshold leakage. These effective low-power digital circuit design approaches reduce the overall power dissipation. In this paper, the characteristics of inverter, twoinput negative-AND (NAND) gate, and half adder digital circuits were analyzed and compared in 45nm, 120nm, 180nm technology nodes by applying several leakage power reduction methodologies to conventional CMOS designs. The sleepy keeper technique when compared to other techniques dissipates less static power. The advantage of the sleepy keeper technique is mainly its ability to preserve the logic state of a digital circuit while reducing …

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The Simulation Study Of A Restructured Residential Low-Voltage Distribution System Microgrid, L. Ramesh, Umamageswari Umamageswari Apr 2025

The Simulation Study Of A Restructured Residential Low-Voltage Distribution System Microgrid, L. Ramesh, Umamageswari Umamageswari

The Journal of Engineering Research

A primary and necessary focus in creating a greener environment is the conversion of existing power-generation sources to renewable power sources in the near future. Another important focus is to develop sustainable household power generation to a low-voltage electricity grid with a power purchase and selling facility. To help with achieving the above vision, the objective of this work is to critically analyze the existing low-voltage distribution system and make suggestions for restructuring it to the low-voltage interconnected microgrid (MG). The test was carried out in the Tamil Nadu Electricity Board (TNEB) 100kVA transformer feeder which was connected to supply …

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Experimental Investigation Of Biogas Production From Kitchen Waste Mixed With Chicken Manure, H. Mousa, A. Obaidat, H.B. Khaled, A. Alawaneh, A. Tarawneh Apr 2025

Experimental Investigation Of Biogas Production From Kitchen Waste Mixed With Chicken Manure, H. Mousa, A. Obaidat, H.B. Khaled, A. Alawaneh, A. Tarawneh

The Journal of Engineering Research

ogas produced from solid kitchen waste (KW) mixed with chicken manure (M) at different mass ratios was investigated. The effect of the ratio of the amount of water to the mixed solid waste on the amount of biogas produced was studied. The results showed that at a fixed ratio of water-to-solid waste, the amount of biogas increased as the amount of chicken M increased. At a fixed M-to-KW ratio, the amount of biogas produced increased as the solid content increased and then decreased, reaching its maximum value at a solid waste-to-water ratio of 1:1. The pH of the bioreactor containing …

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An Investigation Of Excessive Seepage From The Al-Fulaij Recharge Dam, Oman, Y.E.A. Mohamedzein, S.M. Al-Hashmi, A.A. Al-Rawas Apr 2025

An Investigation Of Excessive Seepage From The Al-Fulaij Recharge Dam, Oman, Y.E.A. Mohamedzein, S.M. Al-Hashmi, A.A. Al-Rawas

The Journal of Engineering Research

The Al-Fulaij recharge dam is located on the Al Batinah coast in Oman and was constructed in 1992. The dam is about 3.3 km long and 7.7 m high with a storage capacity of 3.7 million cubic meters of water. It is an earthfill dam with silty, sandy gravel fill in the embankment. Excessive seepage of between 5,000–12,500 m3/day was observed during floods in 1993, and several sinkholes were noticed close to the upstream toe. Remedial work consisting of an upstream blanket and a cutoff trench wall was performed in 2000. However, these remedial measures failed and almost the same …

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Realization Of A Photovoltaic Fed Sparse Alternating Current (Ac)-Link Inverter, R. Ramaprabha, G. Ramya, U. Ashwini, A.H. Fathima Humaira Apr 2025

Realization Of A Photovoltaic Fed Sparse Alternating Current (Ac)-Link Inverter, R. Ramaprabha, G. Ramya, U. Ashwini, A.H. Fathima Humaira

The Journal of Engineering Research

In this paper, a soft-switched alternating current (AC)-link buck-boost inverter with a reduced number of switches, referred to as a sparse AC-link buck-boost inverter, was designed and implemented for a photovoltaic (PV) interface. Important features of the sparse configuration included a lower number of switches, lower failure rates, compactness, and cost-effectiveness. The link was composed of a low reactive rating series inductor/capacitor pair. Significant merits of the AC-link buck-boost inverter are a zero voltage turn on and a soft turn off of the switches, resulting in minimum voltage stress on the switches and negligible switching losses. In this paper, 10 …

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A Comparison Of Trends In Extreme Rainfall Using 20-Year Data In Three Major Cities In Oman, L.N. Gunawardhan, G.A. Al-Rawas Apr 2025

A Comparison Of Trends In Extreme Rainfall Using 20-Year Data In Three Major Cities In Oman, L.N. Gunawardhan, G.A. Al-Rawas

The Journal of Engineering Research

Many regions in the world have recently experienced more frequent and intensive disasters such as flash floods and persistent droughts. The Sultanate of Oman is no exception to this. We analyzed twodecade long daily precipitation records in three major cities, namely, Sohar, Muscat and Salalah, mainly focusing on extremes. A set of climate indices defined in the RClimDex software package was used. Moreover, annual maximum 1-day precipitations in three study areas were analyzed using the Generalized Extreme Value (GEV) distribution function. Results showed significant changes in the precipitation regime in recent years. The annual total precipitation in Sohar and Salalah …

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Performance Of Cement-Based Patch Repair Materials In Plain And Reinforced Concrete Members, A.H. Al-Saidy Apr 2025

Performance Of Cement-Based Patch Repair Materials In Plain And Reinforced Concrete Members, A.H. Al-Saidy

The Journal of Engineering Research

Structural elements such as beams, slabs, and columns may require strengthening or repair during their service life. Different repair materials (RMs) are available and it is usually difficult to choose the best ones, especially when considering the cost of such materials. This paper presents the results of an experimental investigation of patch RMs on plain concrete prisms as well as on reinforced concrete beams. Three cement-based RMs available in the market with different mechanical properties and an ordinary Portland cement (OPC) mix produced in the lab were used in the study. Damage was induced in prisms/beams and then repaired using …

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Vibrations Of Circular Plates With Elastically Restrained Edge Against Translation And Resting On Elastic Foundation, L.B. Rao, C.K. Rao Apr 2025

Vibrations Of Circular Plates With Elastically Restrained Edge Against Translation And Resting On Elastic Foundation, L.B. Rao, C.K. Rao

The Journal of Engineering Research

The present paper deals with exact solutions for the free vibration characteristics of thin circular plates elastically restrained against translation and resting on Winkler-type elastic foundation based on the classical plate theory. Parametric investigations are carried out for estimating the influence of edge restraint against translation and stiffness of the elastic foundation on the natural frequencies of circular plates. The elastic edge restraint against translation and the presence of elastic foundation has been found to have a profound influence on vibration characteristics of the circular plate undergoing free transverse vibrations. Computations are carried out for natural frequencies of vibrations for …

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Single Cfta Based Current-Mode Universal Biquad Filter, S.V. Singh, R.S. Tomar, D.S. Chauhan Apr 2025

Single Cfta Based Current-Mode Universal Biquad Filter, S.V. Singh, R.S. Tomar, D.S. Chauhan

The Journal of Engineering Research

This paper introduces a new current-mode (CM) universal biquad filter structure with optimum number of active and passive elements. In the design, the proposed circuit uses a single active element namely, current follower trans-conductance amplifier (CFTA) and two grounded capacitors as passive elements. The main feature of the proposed circuit is that it can realize all five standard filtering functions such as low pass (LP), band pass (BP), high pass (HP), band stop (BS) and all pass (AP) responses across an explicit high impedance output terminal through the appropriate selection of three inputs. In addition, the same circuit is also …

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Sustainability In Small And Medium-Sized Manufacturing Enterprises: An Empirical Study, I. Garbie Apr 2025

Sustainability In Small And Medium-Sized Manufacturing Enterprises: An Empirical Study, I. Garbie

The Journal of Engineering Research

The main goal of this paper is to analyze and investigate sustainable practices in small and medium-sized manufacturing enterprises (SMEs). A comprehensive analysis and a mathematical framework are used to assess the sustainability indexes (SDIs) of each aspect/issue and pillar/dimension, and of the whole manufacturing enterprise. Sustainability in the whole manufacturing enterprise is represented by the sustainable development index (SDI). The results show that there is a significant difference in SDIs between aspects and dimensions, with economic sustainability representing the highest percentage in the SDI. Also, the results show that industrial companies are adopting sustainable practices and applying them to …

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Prediction Of Permanent Deformation Of Foamed And Emulsified Sulfur Asphalt Soils Mixes, H.I. Al-Abdul Wahhab, G.M.S. Abdullah Apr 2025

Prediction Of Permanent Deformation Of Foamed And Emulsified Sulfur Asphalt Soils Mixes, H.I. Al-Abdul Wahhab, G.M.S. Abdullah

The Journal of Engineering Research

This paper presents a study carried out to evaluate and compare the permanent deformation of marginal soils. Under consideration were marl, sabkha and dune sand stabilized with foamed and emulsified sulfur asphalt (FSA, ESA) with mixes of the same soils stabilized with conventional foamed and emulsified asphalt (FA, EA) for road base construction. Designed mixes at their optimum asphalt content were evaluated for the dynamic resilient modulus (MR) at 22 °C and 40 °C and dynamic triaxial at three levels of deviatoric stress and at 22 °C and 40 °C. The wheel tracking (WT) test was carried out at 22 …

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Semi Interlocking Masonry As Infill Wall System For Earthquake Resistant Buildings: A Review, Y. Totoev, A. Al Harthy Apr 2025

Semi Interlocking Masonry As Infill Wall System For Earthquake Resistant Buildings: A Review, Y. Totoev, A. Al Harthy

The Journal of Engineering Research

Masonry is one of the most popular building materials. It has many excellent material properties and proven durability. Over time, masonry structures have evolved from massive walls, which work mainly through compression, to more slender walls, which could also experience tension and shear. Earthquake-induced tensile and shear stresses often exceed the capacity of traditional unreinforced masonry resulting in substantial damage and failure. A new mortar-less masonry system called semi-interlocking masonry (SIM) is presented in this paper. It has reduced stiffness and susceptibility to damage and utilized a special method of interlocking bricks that allows relative sliding of brick courses in-plane …

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Effect Of Sediment Density On The Bed Topography In A Channel Bend Using Numerical Modeling, M. Vaghefi, Y. Safarpoor, S.S. Hashemi Apr 2025

Effect Of Sediment Density On The Bed Topography In A Channel Bend Using Numerical Modeling, M. Vaghefi, Y. Safarpoor, S.S. Hashemi

The Journal of Engineering Research

In this paper, the bed topography of a channel at a 90-degree bend was studied at the T-shaped spur dike installed at the middle of the outer bank. Numerical analyses were performed with the Sediment Simulation in Intakes with Multiblock Option (SSIIM) model. Three relative curvatures (R/B = 2, 3, and 4) related to the three sediment densities (P = 2.35, 2.5, and 2.65) were modeled in nine cases and the effects of sediment density on the bed scour patterns were studied. It was observed that the maximum amount of scour occurred near the head of the dike wing at …

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Production Of Paperboard Briquette Using Waste Paper And Sawdust, J.K. Odusote, S.A. Onowuma, E.A. Fodeke Apr 2025

Production Of Paperboard Briquette Using Waste Paper And Sawdust, J.K. Odusote, S.A. Onowuma, E.A. Fodeke

The Journal of Engineering Research

Nigeria has abundant supplies of biomass resources and agro-forestry residues (waste), including sawdust, whose potentials are yet to be fully utilized for economic advantage. This study was undertaken to investigate the properties of paperboard briquettes produced from a mixture of shredded waste paper (pulp) and sawdust using starch as binder. The paperboard briquettes were produced manually by compressing soaked mixtures of pulp and sawdust in a wooden mould (28 cm x 28 cm x 1 cm) with a compressive load of 26 kg in the mixing ratios (by weight) 100:0, 70:30, 50:50, 70:30, and 0:100 of pulp to sawdust, respectively. …

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Performance Analysis Of A Multiple Micro-Jet Impingements Cooling Model, A. Husain, N.A. Al-Azri, A. Samad, K.Y. Kim Apr 2025

Performance Analysis Of A Multiple Micro-Jet Impingements Cooling Model, A. Husain, N.A. Al-Azri, A. Samad, K.Y. Kim

The Journal of Engineering Research

The present study investigates the thermal performance of a multiple micro-jet impingements model for electronics cooling. The fluid flow and heat transport characteristics were investigated for steady incompressible laminar flow by solving three-dimensional (3D) Navier-Stokes equations. Several parallel and staggered micro-jet configurations (ie. inline 2 Å~ 2, 3 Å~ 3 and 4 Å~ 4 jets, and staggered five-jet and 13-jet arrays with the jet diameter to the channel height ratios from 0.25–0.5) were analyzed at various flow rates for the maximum temperature rise, pressure drop, heat-transfer coefficient, thermal resistance, and pumping power characteristics. The parametric investigation was carried out based …

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Stochastic Allocation Of Transmit Power For Realistic Wireless Channel Models, N. G. Tarhuni, M. Elmusrati, M. Al-Nadabi Apr 2025

Stochastic Allocation Of Transmit Power For Realistic Wireless Channel Models, N. G. Tarhuni, M. Elmusrati, M. Al-Nadabi

The Journal of Engineering Research

Control of transmitted power is crucial for the successful operation of multi-user wireless channels communications. There are practical situations in which the transmitted power cannot be adjusted by feedback information; hence, only forward transmit power allocation can be applied, especially in situations where a feedback channel is not available in a wireless network or when wireless nodes are only transmit types. Conventionally, transmitted power can be fixed. Higher gain may be observed if the sensors’ transmitted power is randomized. In this work, random power allocation for a Nakagami-m distributed wireless channel model was investigated, and a number of random distributions …

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Optimization Of Process Design Problems Using Differential Evolution Algorithm, A.M. Gujarathia, G. Vakili-Nezhaad, M. Vatani Apr 2025

Optimization Of Process Design Problems Using Differential Evolution Algorithm, A.M. Gujarathia, G. Vakili-Nezhaad, M. Vatani

The Journal of Engineering Research

A modified differential evolution algorithm (MDE) has been used for solving different process related design problems (namely calculation of the NRTL and Two-Suffix Margules activity coefficient models parameters in 20 ternary extraction systems including different ionic liquids and reactor network design problem). The obtained results, in terms of root mean square deviations (rmsd) for these models are satisfactory, with the overall values of 0.0023 and 0.0170 for 169 tie-lines for NRTL and Two-Suffix Margules models, respectively. The results showed that the MDE algorithm results in better solutions compared to the previous work based on genetic algorithm (GA) for correlating liquid-liquid …

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