Open Access. Powered by Scholars. Published by Universities.®

Engineering Commons

Open Access. Powered by Scholars. Published by Universities.®

Discipline
Institution
Keyword
Publication Year
Publication
Publication Type
File Type

Articles 30811 - 30840 of 196358

Full-Text Articles in Engineering

Effect Of 3d Printing Parameters On The Fatigue Properties Of Parts Manufactured By Fused Filament Fabrication: A Review, Hamed Bakhtiari, Muhammad Aamir, Majid Tolouei-Rad Jan 2023

Effect Of 3d Printing Parameters On The Fatigue Properties Of Parts Manufactured By Fused Filament Fabrication: A Review, Hamed Bakhtiari, Muhammad Aamir, Majid Tolouei-Rad

Research outputs 2022 to 2026

The advancement in 3D printing techniques has raised the hope to use additively manufactured parts as final products in various industries. However, due to the layer-by-layer nature of AM parts, they are highly susceptible to failure when they are subjected to fatigue loading. This review provides a detailed account of the influence of 3D printing parameters on the fatigue properties of parts manufactured by fused filament fabrication (FFF). Existing standards for fatigue testing of polymers and their limitation for 3D-printed parts are discussed. In addition, the cyclic behaviour of polymers is reviewed, and the impact of 3D printing parameters on …


Improved Rate Of Secret Key Generation Using Passive Re-Configurable Intelligent Surfaces For Vehicular Networks, Hina Ayaz, Muhammad Waqas, Ghulam Abbas, Ziaul Haq Abbas, Muhammad Bilal, Kyung-Sup Kwak Jan 2023

Improved Rate Of Secret Key Generation Using Passive Re-Configurable Intelligent Surfaces For Vehicular Networks, Hina Ayaz, Muhammad Waqas, Ghulam Abbas, Ziaul Haq Abbas, Muhammad Bilal, Kyung-Sup Kwak

Research outputs 2022 to 2026

The reconfigurable intelligent surfaces (RIS) is a new technology that can be utilized to provide security to vehicle-to-vehicle (V2V) communications at the physical layer. In this paper, we achieve a higher key generation rate for V2V communications at lower cost and computational complexity. We investigate the use of a passive RIS as a relay, to introduce channel diversity and increase the key generation rate (KGR), accordingly. In this regard, we consider the subsets of consecutive reflecting elements instead of the RIS as a whole in a time slot, i.e., instead of a single reflector, the subsets of reflectors are utilized …


Multivariate Cross-Validation And Measures Of Accuracy And Precision, Ute Mueller, Sangga Rima Roman Selia, Raimon Tolosana-Delgado Jan 2023

Multivariate Cross-Validation And Measures Of Accuracy And Precision, Ute Mueller, Sangga Rima Roman Selia, Raimon Tolosana-Delgado

Research outputs 2022 to 2026

Cross-validation and performance measures are standard components in the evaluation of a geostatistical model. These are well established in the univariate case, but measures for multivariate geostatistical modeling have not received as much attention. In the case of a single target variable, the univariate approaches remain valid, but in the fully multivariate case where a vector of variables needs to be estimated, the evaluation needs to be based on all estimates simultaneously. An extension of cross-validation and associated performance measures to the fully multivariate case is presented and discussed for the case of regionalized compositions. The method is demonstrated by …


A Provable Secure And Efficient Authentication Framework For Smart Manufacturing Industry, Muhammad Hammad, Akhtar Badshah, Ghulam Abbas, Hisham Alasmary, Muhammad Waqas, Wasim A. Khan Jan 2023

A Provable Secure And Efficient Authentication Framework For Smart Manufacturing Industry, Muhammad Hammad, Akhtar Badshah, Ghulam Abbas, Hisham Alasmary, Muhammad Waqas, Wasim A. Khan

Research outputs 2022 to 2026

Smart manufacturing is transforming the manufacturing industry by enhancing productivity and quality, driving growth in the global economy. The Internet of Things (IoT) has played a crucial role in realizing Industry 4.0, where machines can communicate and interact in real-time. Despite these advancements, security remains a major challenge in developing and deploying smart manufacturing. As cyber-attacks become more prevalent, researchers are making security a top priority. Although IoT and Industrial IoT (IIoT) are used to establish smart industries, these systems remain vulnerable to various types of attacks. To address these security issues, numerous authentication methods have been proposed. However, many …


Comparative Static And Dynamic Analyses Of Solvents For Removal Of Asphaltene And Wax Deposits Above- And Below-Surface At An Iranian Carbonate Oil Field, Milad Norouzpour, Amin Azdarpour, Rafael M. Santos, Ali Esfandiarian, Moein Nabipour, Erfan Mohammadian, Abbas K. Manshad, Alireza Keshavarz Jan 2023

Comparative Static And Dynamic Analyses Of Solvents For Removal Of Asphaltene And Wax Deposits Above- And Below-Surface At An Iranian Carbonate Oil Field, Milad Norouzpour, Amin Azdarpour, Rafael M. Santos, Ali Esfandiarian, Moein Nabipour, Erfan Mohammadian, Abbas K. Manshad, Alireza Keshavarz

Research outputs 2022 to 2026

During production from oil wells, the deposition of asphaltene and wax at surface facilities and porous media is one of the major operational challenges. The crude oil production rate is significantly reduced due to asphaltene deposition inside the reservoir. In addition, the deposition of these solids inside the surface facilities is costly to oil companies. In this study, the efficiency of different solvents in dissolving asphaltene and wax was investigated through static and dynamic tests. The analysis of solid deposits from the surface choke of one of the Iranian carbonate oil fields showed that they consisted of 41.3 wt % …


Conife-Layered Double Hydroxide Decorated Co-N-C Network As A Robust Bi-Functional Oxygen Electrocatalyst For Zinc-Air Batteries, Yasir Arafat, Yijun Zhong, Muhammad R. Azhar, Mohammad Asif, Moses O. Tadé, Zongping Shao Jan 2023

Conife-Layered Double Hydroxide Decorated Co-N-C Network As A Robust Bi-Functional Oxygen Electrocatalyst For Zinc-Air Batteries, Yasir Arafat, Yijun Zhong, Muhammad R. Azhar, Mohammad Asif, Moses O. Tadé, Zongping Shao

Research outputs 2022 to 2026

Rechargeable zinc-air batteries (ZABs) are cost-effective energy storage devices and display high-energy density. To realize high round-trip energy efficiency, it is critical to develop durable bi-functional air electrodes, presenting high catalytic activity towards oxygen evolution/reduction reactions together. Herein, we report a nanocomposite based on ternary CoNiFe-layered double hydroxides (LDH) and cobalt coordinated and N-doped porous carbon (Co-N-C) network, obtained by the in-situ growth of LDH over the surface of ZIF-67-derived 3D porous network. Co-N-C network contributes to the oxygen reduction reaction activity, while CoNiFe-LDH imparts to the oxygen evolution reaction activity. The rich active sites and enhanced electronic and mass …


Editorial: Rock Physics Modeling And Well-Log Practice For Unconventional Reservoirs, Qiaomu Qi, Lidong Dai, Maxim Lebedev, Tobias Müller, Junfang Zhang Jan 2023

Editorial: Rock Physics Modeling And Well-Log Practice For Unconventional Reservoirs, Qiaomu Qi, Lidong Dai, Maxim Lebedev, Tobias Müller, Junfang Zhang

Research outputs 2022 to 2026

Unconventional resources with commercial interest in the world mainly include heavy oils, shales, coalbed methane and tight gas sands. The production and development of these resources have changed the supply pattern of global energy. Quantitative interpretation of geophysical data in the exploration, well logging and engineering development of the unconventional resources requires a comprehensive understanding of the physical properties of rocks and their relationships. The research of rock physics provides an interdisciplinary treatment of physical properties, whether it is highly related to geological, geophysical and geomechanical methodologies. The development of new rock physics methods is essential when integrating core, well-log, …


Experimental Assessment Of Hole Quality And Tool Condition In The Machining Of An Aerospace Alloy, Muhammad Aamir, Aamer Sharif, Muhammad Z. Zahir, Khaled Giasin, Majid Tolouei-Rad Jan 2023

Experimental Assessment Of Hole Quality And Tool Condition In The Machining Of An Aerospace Alloy, Muhammad Aamir, Aamer Sharif, Muhammad Z. Zahir, Khaled Giasin, Majid Tolouei-Rad

Research outputs 2022 to 2026

This paper deals with an experimental investigation of hole quality in Al2024-T3, which is one of the aerospace alloys used in aircraft fuselage skin due to its high level of resistance to fatigue crack propagation. The experiments are conducted with 6 mm uncoated carbide and HSS drill bits using a CNC machine under dry conditions and different drilling parameters. The characteristics of the hole quality are investigated in terms of its perpendicularity, cylindricity, circularity and hole size. An ANOVA (analysis of variance) and Pareto charts are used to analyze the effects of the drilling parameters on the hole quality. The …


Inelastic Behavior Of Steel And Composite Frame Structure Subjected To Earthquake Loading, P. D. Gajbhiye, Nuha S. Mashaan, V. Bhaiya, Rajan L. Wankhade, S. P. Vishnu Jan 2023

Inelastic Behavior Of Steel And Composite Frame Structure Subjected To Earthquake Loading, P. D. Gajbhiye, Nuha S. Mashaan, V. Bhaiya, Rajan L. Wankhade, S. P. Vishnu

Research outputs 2022 to 2026

Steel construction is used more often these days as an alternative to the R.C.C. when lightweight, high-strength, large-span structures with a faster erection are required. Extensive studies have been conducted by researchers to study the seismic performance of reinforced concrete and steel structures, both in terms of elastic and inelastic behavior. Composite construction is also a recent advancement in the building industry with similar advantages. However, no emphasis has been given to the comparison between the inelastic behavior of steel and composite structures when subjected to lateral loads. This study compares the inelastic behavior of steel and a composite frame …


Role Of Air Staging In A Batch-Type Fixed Bed Biomass Combustor Under Constant Primary Air, Awais Junejo, Yasir M. Al-Abdeli, Jacobo Porteiro Jan 2023

Role Of Air Staging In A Batch-Type Fixed Bed Biomass Combustor Under Constant Primary Air, Awais Junejo, Yasir M. Al-Abdeli, Jacobo Porteiro

Research outputs 2022 to 2026

Staged combustion of biomass is the most suitable thermo-chemical conversion for achieving lower gaseous emissions and higher fuel conversion rates. In a staged fixed bed combustion of biomass, combustion air is supplied in two stages. In the first stage, primary air is provided below the fuel, whereas in the later stage, secondary air is supplied in the freeboard region. The available literature on the effects of air staging (secondary air location) at a constant primary air flow rate on combustion characteristics in a batch-type fixed bed combustor is limited and hence warrants further investigations. This study resolves the effect of …


An Investigation Of The Morphological, Thermal, Mechanical, And Barrier Properties Of An Active Packaging Containing Micro- And Nano-Sized Zno Particles, Raihan Syarifa, Yasaman Esmaeili, Shima Jafarzadeh, Farhad Garavand, Shahrom Mahmud, Fazilah Ariffin Jan 2023

An Investigation Of The Morphological, Thermal, Mechanical, And Barrier Properties Of An Active Packaging Containing Micro- And Nano-Sized Zno Particles, Raihan Syarifa, Yasaman Esmaeili, Shima Jafarzadeh, Farhad Garavand, Shahrom Mahmud, Fazilah Ariffin

Research outputs 2022 to 2026

Biodegradable films are extremely important for food packaging applications since they minimize environmental effects. However, their application areas are limited due to insufficient characteristics required for particular applications. The objective of the present research was to improve the properties of sago-based biodegradable films embedded with nano- and micro-ZnO (zinc oxide). Nano and micro-ZnO were incorporated in the films at different percentages (1%, 3%, and 5%) in that the films were formed using the solvent casting method. The physicochemical, barrier, thermal, optical, morphology, and mechanical properties of sago-based films were investigated. Adding 5% of micro- and nano-ZnO significantly improved film thickness …


Nanoscale Oxygenous Heterogeneity In Fepc Glass For Highly Efficient And Reusable Catalytic Performance, Qi Chen, Lingyu Guo, Haoxiang Di, Zhigang Qi, Zhaoxuan Wang, Ziqi Song, Laichang Zhang, Lina Hu, Weimin Wang Jan 2023

Nanoscale Oxygenous Heterogeneity In Fepc Glass For Highly Efficient And Reusable Catalytic Performance, Qi Chen, Lingyu Guo, Haoxiang Di, Zhigang Qi, Zhaoxuan Wang, Ziqi Song, Laichang Zhang, Lina Hu, Weimin Wang

Research outputs 2022 to 2026

Metallic glass, with its unique disordered atomic structure and high density of low-coordination sites, is regarded as the most competitive new catalyst for environmental catalysis. However, the efficiency and stability of metallic glass catalysts are often affected by their atomic configuration. Thus, the design and regulation of the nanoscale structure of metallic glasses to improve their catalytic efficiency and stability remains a challenge. Herein, a non-noble component, Fe75P15C10 amorphous ribbon, is used as a precursor to fabricate a hierarchical gradient catalyst with nanoscale heterogeneous and oxygenous amorphous structure by simple annealing and acid-immersing. The resulting catalyst offers an ultrahigh catalytic …


Strong And Ductile Al–Mn–Mg–Sc–Zr Alloy Achieved In Fabrication-Rate Enhanced Laser Powder Bed Fusion, Hao Zhang, Lai Chang Zhang, Hongyu Liu, Xiaodong Niu, Marcus C. Lam, Wenzhe Zhang, Xiaojie Jin, Fuzhong Chu, Xinhua Wu, Sheng Cao Jan 2023

Strong And Ductile Al–Mn–Mg–Sc–Zr Alloy Achieved In Fabrication-Rate Enhanced Laser Powder Bed Fusion, Hao Zhang, Lai Chang Zhang, Hongyu Liu, Xiaodong Niu, Marcus C. Lam, Wenzhe Zhang, Xiaojie Jin, Fuzhong Chu, Xinhua Wu, Sheng Cao

Research outputs 2022 to 2026

The high cost of laser powder bed fusion (LPBF) fabricated high-strength Sc containing aluminium alloy hinders its applications. To reduce the cost, we reported a LPBF fabricated strong and ductile Al–Mn–Mg–Sc–Zr alloy using large layer thicknesses to improve the fabrication efficiency on coarse powder particles. A high relative density exceeding 99.2% was achieved at layer thicknesses up to 120 μm. In post-process heat-treated specimens, the yield strength only had a slight 6% decrease from layer thickness of 30 to 120 μm; such a decrease in strength was attributed to the larger grain size resulted from the adopted larger layer thickness. …


Influence Of Soil Fabric On Dynamic Properties Of Sand: An Experimental Study, Arpit Jain, Satyendra Mittal, Sanjay K. Shukla Jan 2023

Influence Of Soil Fabric On Dynamic Properties Of Sand: An Experimental Study, Arpit Jain, Satyendra Mittal, Sanjay K. Shukla

Research outputs 2022 to 2026

Natural field sites originate under the action of external sources such as rivers, wind, or marine environments. These sources are responsible for constituting a variety of soil fabrics, which ultimately modify the deformation characteristics. Additionally, the dynamic properties of a site present the characterization of a region and have been profusely utilized by field engineers and researchers. In the present study, the dynamic properties of soil specimens have been evaluated for specimen preparation techniques, namely, air pluviation (AP) and water sedimentation (WS). The cyclic triaxial tests were conducted on the strain-controlled consolidated undrained specimens at a frequency of 0.1 Hz. …


Investigating The Potential Of High-Density Polyethylene And Nano Clay Asphalt-Modified Binders To Enhance The Rutting Resistance Of Asphalt Mixture, Ashraf Abdel-Raheem, Anmar Dulaimi, Ahmed S. Mohamed, Ghada S. Moussa, Yasin O. Özkılıç, Nuha Mashaan, Ramadhansyah P. Jaya, Talaat Abdel-Wahed Jan 2023

Investigating The Potential Of High-Density Polyethylene And Nano Clay Asphalt-Modified Binders To Enhance The Rutting Resistance Of Asphalt Mixture, Ashraf Abdel-Raheem, Anmar Dulaimi, Ahmed S. Mohamed, Ghada S. Moussa, Yasin O. Özkılıç, Nuha Mashaan, Ramadhansyah P. Jaya, Talaat Abdel-Wahed

Research outputs 2022 to 2026

This study investigates the potential of two bitumen modifiers, high-density polyethylene (HDPE) and nano clay (NC), to enhance the rutting resistance of asphalt mixture. Four HDPE asphalt binders were prepared by mixing the HDPE at percentages of 2%, 4%, 6%, and 8% with the virgin binder, while four NC asphalt binders were produced by mixing the NC at percentages of 1%, 2%, 3%, and 4%. The consistency and flow of virgin binder, HDPE binders, and NC binders were evaluated by penetration, softening point, and viscosity tests. The results show a gradual increment in the binder stiffness by increasing the percentage …


Physical Layer Authenticated Image Encryption For Iot Network Based On Biometric Chaotic Signature For Mpfrft Ofdm System, Esam A. A. Hagras, Saad Aldosary, Haitham Khaled, Tarek Hassan Jan 2023

Physical Layer Authenticated Image Encryption For Iot Network Based On Biometric Chaotic Signature For Mpfrft Ofdm System, Esam A. A. Hagras, Saad Aldosary, Haitham Khaled, Tarek Hassan

Research outputs 2022 to 2026

In this paper, a new physical layer authenticated encryption (PLAE) scheme based on the multi-parameter fractional Fourier transform–Orthogonal frequency division multiplexing (MP-FrFT-OFDM) is suggested for secure image transmission over the IoT network. In addition, a new robust multi-cascaded chaotic modular fractional sine map (MCC-MF sine map) is designed and analyzed. Also, a new dynamic chaotic biometric signature (DCBS) generator based on combining the biometric signature and the proposed MCC-MF sine map random chaotic sequence output is also designed. The final output of the proposed DCBS generator is used as a dynamic secret key for the MPFrFT OFDM system in which …


The Compressive Strength And Microstructure Of Alkali-Activated Mortars Utilizing By-Product-Based Binary-Blended Precursors, Otman M. M. Elbasir, Megat A. M. Johari, Zainal A. Ahmad, Nuha S. Mashaan, Abdalrhman Milad Jan 2023

The Compressive Strength And Microstructure Of Alkali-Activated Mortars Utilizing By-Product-Based Binary-Blended Precursors, Otman M. M. Elbasir, Megat A. M. Johari, Zainal A. Ahmad, Nuha S. Mashaan, Abdalrhman Milad

Research outputs 2022 to 2026

Researchers have investigated the feasibility of using ultrafine palm oil fuel ash (u-POFA) as a cement replacement material because of its potential to reduce the environmental impact of concrete production. u-POFA, a by-product of palm oil fuel combustion, is a suitable replacement for Portland cement in concrete mixes because of its sustainability and cost-effectiveness. This study investigated the microstructural and compressive strengths of alkali-activated mortars (AAMs) based on fly ash (FA) and granulated blast-furnace slag (GBFS) being added with varying percentages of u-POFA. The mixture samples were prepared in eighteen mortars using sodium metasilicate (Na2SiO3) as the source material and …


Thermal Curing Effects On Alkali-Activated Treated Soils With Palm Oil Fuel Ash, Lokmane Abdeldjouad, Wisam Dheyab, Yaser Gamil, Afshin Asadi, Sanjay K. Shukla Jan 2023

Thermal Curing Effects On Alkali-Activated Treated Soils With Palm Oil Fuel Ash, Lokmane Abdeldjouad, Wisam Dheyab, Yaser Gamil, Afshin Asadi, Sanjay K. Shukla

Research outputs 2022 to 2026

Regarding the significance of binder quantity, alkali activator molarities, and thermal curing, this work was utilized to geopolymerize with a potassium-based alkaline activator to strengthen soils. Five different molarities of palm oil fuel ash (POFA) in four different amounts were utilized to activate the clayey soil. POFA admixtures have been used to test soils. The results showed that for mixtures with 10 and 12.5 molarities, the unconfined compressive strength (UCS) with 15 % and 20 % of POFA was stronger. Comparing the strengths of the blends with various POFA amounts and concentration molarities allowed for this determination. To increase the …


Hydrogen-Wettability Alteration Of Indiana Limestone In The Presence Of Organic Acids And Nanofluid, Mirhasan Hosseini, Rossen Sedev, Mujahid Ali, Muhammad Ali, Jalal Fahimpour, Alireza Keshavarz, Sefan Iglauer Jan 2023

Hydrogen-Wettability Alteration Of Indiana Limestone In The Presence Of Organic Acids And Nanofluid, Mirhasan Hosseini, Rossen Sedev, Mujahid Ali, Muhammad Ali, Jalal Fahimpour, Alireza Keshavarz, Sefan Iglauer

Research outputs 2022 to 2026

This study focuses on the wettability alteration (changing from a hydrophobic state to a hydrophilic state) of Indiana limestone for hydrogen (H2) geological storage. We examine the effect of hexanoic acid C6, lauric acid C12, and stearic acid C18, on the wettability of Indiana limestone at ambient (298 K and 0.1 MPa) and reservoir (323 K and 8.27 MPa) conditions. The effects of silica nanofluids (silica with deionized water) at various concentrations (0.1 wt%, 0.25 wt%, and 0.5 wt%) on the wettability reversal of stearic-aged samples were tested at ambient and reservoir …


Comparative Study On Development Of Novel Catalytic Oxidation For Removing Emerging Contaminants, Abdul H. Asif Jan 2023

Comparative Study On Development Of Novel Catalytic Oxidation For Removing Emerging Contaminants, Abdul H. Asif

Theses: Doctorates and Masters

‘Wastewater treatment’ is not itself a new concept, where global water bodies have been polluted since the evolution of mankind. As a result of human activities including domestic, industrial and commercial practices, levels of water pollution through aqueous contaminants are increasing every day. Moreover, rapid industrialisation and recent human progress has given rise to a new classification of pollution, that of emerging contaminants (ECs). Further, these chemicals are highly resistant to biodegradation and are capable of travelling, where they can penetrate from one part of the world to another. Whilst traditional wastewater treatment techniques, such as adsorption, might be effective …


Experimental Investigation Of The Interface And Wetting Characteristics Of Rock-H2-Brine Systems For H2 Geological Storage, Mirhasan Hosseini Jan 2023

Experimental Investigation Of The Interface And Wetting Characteristics Of Rock-H2-Brine Systems For H2 Geological Storage, Mirhasan Hosseini

Theses: Doctorates and Masters

The projected rise in demand for hydrogen (H2) production is a response to several factors, including greenhouse gas emissions caused by burning fossil fuels, depletion of fossil fuel reserves, and their uneven distribution around the earth. Thus, increased requirement for large-scale hydrogen storage solutions is anticipated to overcome imbalance between energy demand and supply. Deep underground formations such as salt caverns and porous reservoir rocks (e.g., depleted hydrocarbon reservoirs and deep saline aquifers) are necessary to achieve such volumes in practice. This process is known as underground hydrogen storage (UHS) which is technically very similar to underground natural gas storage. …


Heterogeneous Microstructure And Mechanical Behaviour Of Al-8.3fe-1.3v-1.8si Alloy Produced By Laser Powder Bed Fusion, S. J. Yu, P. Wang, H. C. Li, R. Setchi, M. W. Wu, Z. Y. Liu, Z. W. Chen, S. Waqar, Lai-Chang Zhang Jan 2023

Heterogeneous Microstructure And Mechanical Behaviour Of Al-8.3fe-1.3v-1.8si Alloy Produced By Laser Powder Bed Fusion, S. J. Yu, P. Wang, H. C. Li, R. Setchi, M. W. Wu, Z. Y. Liu, Z. W. Chen, S. Waqar, Lai-Chang Zhang

Research outputs 2022 to 2026

The relationship between processing parameters, microstructure, and mechanical properties of Al-8.3Fe-1.3V-1.8Si alloy processed by laser powder bed fusion is seldom studied. Therefore, fully dense alloys with two parameters were selected to investigate this key issue. The results show that the alloy with low power and scanning speed (S200) shows fan-shell-shaped melt pools and laser tracks while another (S350) shows a deeper and wider melt pool. Both alloys obtain a heterogeneous microstructure without a secondary phase in melt pool (MP) and a nano-sized phase in melt pool boundary (MPB). The difference between solid-solution strengthening and Orowan strengthening in MP and MPB …


Artifacts In Localised Multivariate Uniform Conditioning: A Case Study, Oscar Rondon, Hassan Talebi Jan 2023

Artifacts In Localised Multivariate Uniform Conditioning: A Case Study, Oscar Rondon, Hassan Talebi

Research outputs 2022 to 2026

Localised Multivariate Uniform Conditioning (LMUC) is a technique designed for spatially locating Selective Mining Unit (SMU) grades derived using Multivariate Uniform Conditioning (MUC) for the assessment of recoverable resources. LMUC has the advantage of producing SMU estimates conforming to the MUC panel-specific grade-tonnage curves while preserving the spatial grade distribution at the selective mining level. However, LMUC results have two severe artifacts. This paper documents both artifacts using four grades from a large nickel–cobalt laterite deposit in Western Australia.


A New Volumetric Strain-Based Method For Determining The Crack Initiation Threshold Of Rocks Under Compression, Hao Li, Ruizhi Zhong, Leo Pel, David Smeulders, Zhenjiang You Jan 2023

A New Volumetric Strain-Based Method For Determining The Crack Initiation Threshold Of Rocks Under Compression, Hao Li, Ruizhi Zhong, Leo Pel, David Smeulders, Zhenjiang You

Research outputs 2022 to 2026

The crack initiation stress threshold ( ci) is an essential parameter in the brittle failure process of rocks. In this paper, a volumetric strain response method (VSRM) is proposed to determine the σci based on two new concepts, i.e., the dilatancy resistance state index ( ci) and the maximum value of the dilatancy resistance state index difference (| ci|), which represent the state of dilatancy resistance of the rock and the shear sliding resistance capacity of the crack-like pores during the compressive period, respectively. The deviatoric stress corresponding to the maximum | ci| is taken as the ci . We …


Optimizing Technical And Economic Aspects Of Off-Grid Hybrid Renewable Systems: A Case Study Of Manoka Island, Cameroon, Reagan J. J. Molu, Serge R. D. Naoussi, Patrice Wira, Wulfran F. Mbasso, Saatong T. Kenfack, Barun K. Das, Enas Ali, Muhannad J. Alshareef, Sherif S. M. Ghoneim Jan 2023

Optimizing Technical And Economic Aspects Of Off-Grid Hybrid Renewable Systems: A Case Study Of Manoka Island, Cameroon, Reagan J. J. Molu, Serge R. D. Naoussi, Patrice Wira, Wulfran F. Mbasso, Saatong T. Kenfack, Barun K. Das, Enas Ali, Muhannad J. Alshareef, Sherif S. M. Ghoneim

Research outputs 2022 to 2026

The lack of accessible and reliable electrical energy in Cameroon has become a pervasive obstacle to the nation's progress, with energy availability, quality, and cost identified as key hindrances to development over the past 15 years. Conventional solutions that rely on combustion engines and electrochemical storage systems have proven to be cost-prohibitive, limited in power output, and constrained in capacity. The dependence on traditional diesel generators has perpetuated maintenance challenges and a continuous demand for fuel supply, while the accompanying noise and pollution have restricted their use in residential areas. Recognizing the imperative of reducing dependence on fossil fuels and …


Natural Manganese Ores For Efficient Removal Of Organic Pollutants Via Catalytic Peroxymonosulfate-Based Advanced Oxidation Processes, Zhengxin Yao, Roufei Chen, Ning Han, Hongqi Sun, Ngie Hing Wong, Lusi Ernawati, Shaobin Wang, Jaka Sunarso, Shaomin Liu Jan 2023

Natural Manganese Ores For Efficient Removal Of Organic Pollutants Via Catalytic Peroxymonosulfate-Based Advanced Oxidation Processes, Zhengxin Yao, Roufei Chen, Ning Han, Hongqi Sun, Ngie Hing Wong, Lusi Ernawati, Shaobin Wang, Jaka Sunarso, Shaomin Liu

Research outputs 2022 to 2026

Peroxymonosulfate-based advanced oxidation processes (PMS-AOPs) for in situ persistent organic pollutant (POP) remediation in aqueous solutions can be a promising technology. However, this technology is constrained by its high toxicity and cost of metal oxide and non-metal catalysts for PMS activation. Here, we investigated the catalytic performance of a widely available natural mineral, manganese ore (MO), for PMS activation. A series of natural MO samples in an aqueous solution were prepared via the Fenton-like reaction. The samples' crystalline structure, surface morphology, textural properties, and other surface characteristics of the selected MO were systematically characterized. The effects of PMS concentration and …


Corrosion Behavior And Mechanisms Of The Heat-Treated Ti5cu Produced By Laser Powder Bed Fusion, Xin Wang, Peng Qin, L. Y. Chen, Hongqi Sun, Laichang Zhang Jan 2023

Corrosion Behavior And Mechanisms Of The Heat-Treated Ti5cu Produced By Laser Powder Bed Fusion, Xin Wang, Peng Qin, L. Y. Chen, Hongqi Sun, Laichang Zhang

Research outputs 2022 to 2026

This work investigated the corrosion behavior of laser powder bed fusion produced (LPBFed) Ti5Cu and its heat-treated counterparts at 740 and 900 °C (named as HT-740 and HT-900 respectively) in Hank’s solution. The results indicated that the presence of acicular a'-Ti phase in LPBFed Ti5Cu was beneficial to corrosion, but the corrosion resistance of HT-740 and HT-900 were increased owing to the dual-phase microstructure (a'/a-Ti + Ti2Cu) or the increased content of Ti2Cu phase in the microstructure. The Ti2Cu phase could provide an ‘envelope’ protection to the a'/a-Ti phase and slow down the micro-galvanic reaction between a'/a-Ti phase and Ti2Cu …


Modular Product Architecture For Sustainable Flexible Manufacturing In Industry 4.0: The Case Of 3d Printer And Electric Toothbrush, Tufail Habib, Muhammad Omair, Muhammad Salman Habib, Muhammad Zeeshan Zahir, Sikandar Bilal Khattak, Se-Jin Yook, Muhammad Aamir, Rehman Akhtar Jan 2023

Modular Product Architecture For Sustainable Flexible Manufacturing In Industry 4.0: The Case Of 3d Printer And Electric Toothbrush, Tufail Habib, Muhammad Omair, Muhammad Salman Habib, Muhammad Zeeshan Zahir, Sikandar Bilal Khattak, Se-Jin Yook, Muhammad Aamir, Rehman Akhtar

Research outputs 2022 to 2026

Integrating sustainability, a flexible manufacturing system, and Industry 4.0 resolves the issues of fluctuating market demand arising from customization requirements. Modular products allow flexibility to adapt to changing requirements and optimize resource utilization. In this study, a method was proposed and applied to two products, i.e., a 3D printer and an electric toothbrush featuring modular architecture, multiple product versions, and customization, to contribute to the development of sustainable flexible manufacturing systems. From the results of the two case studies nine modules were identified that contain specific functions and related interface information. From these modules, one platform was developed that comprises …


Performance Evaluation Of Single Stand And Hybrid Solar Water Heaters: A Comprehensive Review, Zohreh Rahimi-Ahar, Mehdi Khiadani, Leile Rahimi Ahar, Abdellah Shafieian Jan 2023

Performance Evaluation Of Single Stand And Hybrid Solar Water Heaters: A Comprehensive Review, Zohreh Rahimi-Ahar, Mehdi Khiadani, Leile Rahimi Ahar, Abdellah Shafieian

Research outputs 2022 to 2026

In this review, flat plate and concentrate-type solar collectors, integrated collector–storage systems, and solar water heaters combined with photovoltaic–thermal modules, solar-assisted heat pump solar water heaters, and solar water heaters using phase change materials are studied based on their thermal performance, cost, energy, and exergy efficiencies. The maximum water temperature and thermal efficiencies are enlisted to evaluate the thermal performance of the different solar water heaters. It is found that the solar water heaters’ performance is considerably improved by boosting water flow rate and tilt angle, modification of the shape and number of collectors, using wavy diffuse and electrodepositioned reflector …


Photocatalytic Reforming Of Lignocellulose: A Review, Xinyuan Xu, Lei Shi, Shu Zhang, Zhimin Ao, Jinqiang Zhang, Shaobin Wang, Hongqi Sun Jan 2023

Photocatalytic Reforming Of Lignocellulose: A Review, Xinyuan Xu, Lei Shi, Shu Zhang, Zhimin Ao, Jinqiang Zhang, Shaobin Wang, Hongqi Sun

Research outputs 2022 to 2026

Biomass has been considered as a promising energy resource to combat the exhaustion of fossil fuels, as it is renewable, sustainable, and clean. Photocatalytic reforming is a novel technology to utilize solar energy for upgrading biomass in relatively mild conditions. This process efficiently reforms and recasts biomass into hydrogen and/or valuable chemicals. To date, lignocellulose, including cellulose, hemicellulose and lignin, has attracted extensive studies in facile photocatalytic valorisation. This review summarizes and analyzes the most recent research advances on photoreforming of lignocellulose to provide insights for future research, with a particular emphasis on the reformation of lignin because of its …