bluuebunny/crossref_metadata_2025_split huggingface dataset:
Zeolite as a natural adsorbent for nitrogenous compounds being removed from water
Authors: Abdulredha M , Kadhim N R , Hussein A H , Almutairi M , Alkhaddar R , Yeboah D , Hashim K 
Published: March 2021

Abstract
Water is vital to the survival of humans and all other life forms, yet many sources of freshwater are being contaminated due to pollution, significantly limiting freshwater availability, and threatening human existence. Nitrates and ammonium are common water contaminants whose concentrations in water have increased significantly due to the excessive use of fertilisers. High concentrations of such contaminants in water can lead to multiple health issues, and thus controlling the concentration levels of these pollutants in water grows into the main task for environmental scientists. A natural zeolite filter was employed in this study to minimise traces of contaminants in water. Samples of synthetic polluted water were prepared that contained 50 mg/L of each contaminant for the laboratory tests. Testing natural zeolite doses ranging from 1 to 5 g/L at various pH levels (between 3 and 10) showed that a zeolite filter significantly improved the water quality from the initial concentrations of each pollutant by between 10 and 50 mg/l. In particular, more than 93% of both contaminants (nitrate and ammonium) were removed by using a 5 g/L dose of zeolite in a neutral pH level range for 120 minutes.
Nano and bio-composites and their applications: A review
Authors: Ali M S , Al-Shukri A A , Maghami M R , Gomes C 
Published: March 2021

Abstract
Recent developments in the materials science field have highlighted the need for further composite materials study, especially with regard to bio and nano-composites, as their abilities to meet modern requirements with regard to facilitating technological advancement is far greater than those of monolithic materials. There are several advantages to nano and bio-composites as compared to conventional materials, including properties such as fatigue resistance, impact resistance, stiffness, corrosion resistance, biodegradability, thermal conductivity, low relative density, environmentally friendly waste stages, and high specific strength. Recent years have seen the discovery of several new high-performing composite materials, and improvements in the fields of aviation, automobile, adhesion, building, and electronic engineering also support the adoption of more general utilisation of nano and bio-composites in a much wider range of applications than those for which they were originally designed. This paper thus highlights and reviews information on bio- and nano-composite materials to determine current trends in how these materials are used in the various fields of engineering in numerous applications, and to examine the role of nanotechnology in the enhancement of composite properties.
A Novel Review on Nano-fluid and Phase Change Material based Photovoltaic Thermal (PV/T) Systems
Authors: Shojaeefard M H , Sakran N B , Sharfabadi M M , Davoudi N 
Published: March 2021

AbstractIn this paper, advanced researches on photovoltaic thermal systems are reviewed. First, the PV/T concept and it’s advantageous and disadvantageous are mentioned. Then the latest innovations for improving the performance of PV/T systems such as applying Nano-fluid and Phase Change Material (PCM) and also hybrid-Nano-fluid are discussed. The results of numerical, energy, exergy and experimental studies in this issue have been considered. Investigations show that the utilization of Nano-fluid and PCM improve the thermal efficiency of the PV/T systems and reduce the consumption of fossil fuels.
Simulation of cam-based infinitely variable transmission
Authors: Faleh M , Al-Hamood A , Majeed M H 
Published: March 2021

Abstract
Infinitely variable transmission (IVT) is a system that gives a continuous (non-discrete) variation that includes zero in transmission ratios between two rotating elements. In this paper, a cam based IVT mechanism was designed and simulated using SolidWorks software containing two identical units. Each unit included a cam with a follower and oscillatory slotted links pivoted at a hinge that could be moved vertically by altering the transmission ratio, achieved by using a hydraulic ram or a power screw. system units also include a grooved wheel and a follower or actuator. During operation, the grooved wheels displayed an oscillating rotational motion, so that they are connected to the output shaft via one-way clutches (ratchets) to give the output shafts one-way directional motion. The cam profiles are designed and investigated within the system with regards to performance. A combination of uniform velocity and 1-5 polynomial profiles where selected and designed for the current study In general, the results obtained from the simulation showed compatibility with the expected theoretical results derived from the design of the current IVT system. These results indicated uniform velocity during the power stroke in each unit for all parts in the units. However, the ratchets used in this study produced a noticeable fluctuation in the angular velocity of the output shaft, and further work on the selection and development of more efficient ratchets is thus strongly recommended.
Experimental study on performance improvement of air cooler incorporating two-stages
Authors: Muhsen M M , Abdulrasool A A , Sadiq B R 
Published: March 2021

Abstract
An experimental study was conducted using two compact heat exchangers (air-cooled) to improve indoor air conditions in Iraq summer weather. The layout of the rig is constructed in such a way that the air flows through a two-stage direct/indirect cooling system to minimize the high air temperature. The water in the basin of the unit was then unitized to the second stage as a working fluid. The findings showed that the temperature could be changed to a point 13% lower than that achieved by the standard design at an affordable cost and in an environmentally appropriate manner. The difference in the humidity ratio was also comparatively reduced with respect to the original discharge from the evaporative cooler alone, as the new system eliminates only sensible heat. This new design, is well-suited to hot and dry conditions where the cost of the air conditioning system based on refrigerants is high, the percentage increase in the overall effectiveness is about 25%.
Investigating the effects of post-heat treatment on residual stress in AlSi12 parts processed with Selective Laser Melting
Authors: Ponnusamy P , Masood S H , Ruan D , Palanisamy S , Rashid R A 
Published: March 2021

Abstract
Residual stresses are the stresses that remain on a part after the original cause of any stress has been removed. In Selective Laser Melting (SLM), an additive manufacturing process, residual stress occurs in the created part due to rapid melting and rapid solidification; these stresses are responsible for distortion, which must therefore be minimised or eliminated. Residual stresses can be reduced in SLM built parts by the application of post heat treatment, and this process is investigated in this study. X-ray diffraction was employed for the experimental analysis of the residual stresses in AlSi12 parts processed by SLM that were then subjected to heat treatments at different temperatures, ranging from 200 °C to 500 °C, in order to investigate how residual stresses and microstructure changes vary with heat treatment temperatures.
An examination of the effect of adding zirconia to bioactive glass-ceramic properties
Authors: Aswad M A , Sabree I K , H S Abd Ali 
Published: March 2021

Abstract
Zirconia has been frequently used as a bone substitute based on its material properties and bioinert nature, which make it a suitable composite material for multiple bio applications. In this study, 45S5 bioactive glass ceramic (BGC) (45% SiO2, 24.5% CaO, 24.5% Na2O, 6% P2O5) was synthesised using a melt derivation process. The biocomposite for testing was prepared by mixing 1wt% of ZrO2 with the prepared BGC. The sample of simple BGC was sintered at 900 °C, while the composite was sintered at 1170 °C. XRD diffraction testing confirmed the formation of Na2Ca2Si3O8 and Na2Ca2Si3O9 phases in the structure of pure the BGC sample, while the composite displayed the emergence of tetragonal and monoclinic ZrO2 peaks in addition to bioglass ceramic peaks. SEM testing also showed distinct differences between the structures. The results suggest that adding ZrO2 to the bioactive glass matrix improves its mechanical properties and increases density while decreasing the porosity value.
Frequency-Based Time-of-Use Pricing with Multiple Battery-buffered Smart Loads
Authors: Zurfi Ahmed , Altahir Ali Abdul Razzaq , Al-Doori Bilal. , Zhang Jing 
Published: March 2021

Abstract
This work discusses a new time-of-use energy pricing structure based on grid frequency. Under the proposed pricing structure, energy cost depends on the time of frequency deviation and the period during which energy is used. This pricing mechanism is intended for use with multiple behind-the-meter home batteries as part of a frequency-controlled smart load strategy known as a battery buffered smart load. The load energy consumption from the grid and energy storage rates thus depend on the frequency deviation and hours of use, which means that the proposed pricing encourages battery-using customers to not only utilise energy arbitrage, shifting peak demand but also to contribute to demand-side primary frequency control. The second contribution of this paper is the presentation of an operation strategy for multiple buffered battery smart load units in which charge and discharge decisions are made according to off- and on-peak period information to ensure continuous provision of primary frequency control under the proposed time of frequency division pricing. A MATLAB simulation of the proposed pricing and operation modes of the BBSL was conducted with multiple battery-buffered smart load to assess feasibility.
A Green Data Management Layer in Industrial IoT
Authors: Ghaderi A , Qavany Z , Movahedi Z 
Published: March 2021

AbstractAll Nowadays, industry 4.0, which aims at transforming industrial manufacturing systems to the smart factories, has gained considerable attention from both industry and academia. The Industrial Internet of Things (IIoT) plays a primordial role to achieve the objectives of Industry 4.0, by enabling the Cyber-Physical Production Systems (CPPS) to communicate and cooperate with each other and with humans both internally and across the participants of the supply chain. A communication model used commonly in IIoT networks consists of the publish-subscribe model, in which the data generated by sensor nodes are cached in a central controller to be subsequently consumed by actuator nodes. However, the traditional centralized data management is inappropriate for real application because of its communication overhead and inability to cope with strict delay requirements of IIoT applications and energy constraints of IIoT networks. To address these issues, we propose a Green Data Management Layer (GDML), which caches data distributedly in some IoT nodes, called proxy nodes, so that the network energy consumption is optimized while the constraints on data access latency and IoT nodes’ cache capacity are met. In this measure, the extra IoT nodes not involved in data transmission nor in data caching are switched off to prolong the battery lifetime of constrained IoT nodes. We modeled the aforementioned optimization problem as an Integer Linear Programming (ILP) and solved it using the CPLEX tool. The obtained results show that the proposed GDML outperforms significantly alternative solutions in terms of overall energy consumption, energy consumption devoted to data transmission, energy consumption devoted to keeping active the involved nodes, while the constraints on data applications latency and the cache size of IoT nodes are satisfied.
Domain-Specific Languages for IoT: Challenges and Opportunities
Authors: Salman Aymen J , Al-Jawad Mohammed , Tameemi Wisam Al 
Published: March 2021

Abstract
Internet of Things (IoT) is a multidisciplinary tool used by field experts to fabricate technology into their discipline; these fields experts thus need access to a simple, understandable and user-friendly programming language for this purpose. Domain-Specific Languages (DSL) have been developed to pave the way for such domain experts to integrate IoT capabilities into their everyday tasks. IoT is thus one of the main technologies targeting human day-to-day activities, and the concept of IoT has caused a general rethink and reimagining of the shape of life in the future. Many researchers are thus working on fields related to IoT such as networking, power consumption, data aggregation and fusion, finding ways to offer this new technology for end user access in a smooth and easy manner. Introducing new application development methods and using software engineering standards and tools that enable end-users to develop their own IoT applications is another aspect that has received attention in the last decade; however, this aspect requires more work from the research community. The main contribution of this paper is to highlight current efforts related to the IoT field and to perform quantitative analysis to highlight the current state of the art in both positive and negative terms, including the current limitations and obstacles faced by both end-users and field experts seeking to build their own IoT applications.
Simulation of EEG-Based Apparatus Control for Quadriplegic Patients
Authors: Mohammed Mohammed Jamal , Abed Jameel Kadhim , Mahdi Ali Jafer 
Published: March 2021

Abstract
The use of electroencephalogram (EEG) waves in the field of Brain Computer Interfaces (BCI) has recently attracted a lot of interest, with varied applications ranging from entertainment to medicine emerging, showing that EEG waves are suitable for controlling appliances through a microcontroller. This study presents an offline strategy for the extraction of digital control signals from brain EEG waves using MATLAB/SIMULINK. The principle is applied as follows: (i) the extraction of α- and β-bands from the original brain EEG wave; (ii) detection of the peaks of both bands; and (iii) calculation of the power density of both bands to classify the mental mode and to generate appropriate control signals. Simulation results including signal processing tracking for various EEG waves are demonstrated that verify the effectiveness of the proposed strategy in terms of using brain EEG waves for apparatus control.
The Correlation Between Gastrocnemius Muscle Thickness And Activity Limitations In Patients With Severe OA
Authors: Ghazwan Aseel , Alsaadan Waleed A , Rany Nadia 
Published: March 2021

Abstract
Muscle thickness offers an excellent indicator of maximal force generating capacity, and, accordingly, a reduction in muscle thickness may contribute to muscle weakness; this in turn may be related to functional limitations in patients undergoing total knee replacement. The purpose of this study was to correlate the morphologic changes in the gastrocnemius muscle in relation to muscle activity in subjects with severe knee osteoarthritis (OA), in order to establish an objective means of measuring muscle function and muscle recovery. Two subject groups participated in this study, one group of 10 non-pathological subjects (NP) and a separate group of 10 subjects with severe OA. The muscle thickness (MT) and EMG muscle activity (MA) of the medial gastrocnemius (MG) and lateral gastrocnemius (LG) were assessed using ultrasonography (US) and electromyography (EMG), respectively. The correlation between MA and MT was thus investigated, and linear regression analysis performed to determine prediction equations for muscle activity. The results showed that MA is highly related to MT for both MG and LG in NP subjects. The MA prediction equation based on linear regression analysis resulted in R2 values of 0.90 and 0.95 (p<0.05) for LG and MG, respectively, while in OA subjects, a good correlation was shown between MA and MT within the MG, with R2 = 0.80, though a more moderate correlation was found for LG, with R2 = 0.52. The thickness of the MG was not significantly increased during maximum voluntary contraction (MVC) as compared with the resting state, while the thicknesses of LG significantly increased, from 15 to 22 mm, on moving from resting to MVC. This study thus demonstrated that MG is more useful parameter than LG for the prediction of muscle force generating intensity in patients with severe OA.
Fuzzy logic control of a catalytic naphtha unit
Authors: Ahmed D F , Khalaf I H 
Published: March 2021

AbstractThis work examines the fuzzy logic-based control of a catalytic reformer. The control process requires development of an exact process model valid over a wide range of operating conditions. Two control methods, proportional integral derivative (PID) and Fuzzy-PID, were applied to determine the optimal operating conditions. The output temperature from the feedback fuzzy controller was sent to the PID controllers as a setpoint in the heating system loop, and two fuzzy logic systems, one in the forward path and one in the feedback path were developed to give setpoints for temperature control loops in the four reactors. A fuzzy logic-based optimal control scheme was established to increase the aromatics yield, subject to constraints on the inlet temperature of the reactors. A rigorous kinetic model was then developed by expressing the heat and mass balances under unsteady state conditions. This model was used to determine the temperature and concentration profiles of three main hydrocarbons, naphthenes, paraffins, and aromatics, across the four reactors. A reaction scheme involving 27 pseudo components connected using a network of 71 reactions for components in a wide range of carbon numbers was thus modelled. The simulation results for the model were compared with previous studies to validate the model, and good agreement was found between the reformate composition of the proposed model and the plant reformate composition and temperature. The simulation results also showed that the PID –Fuzzy controller is accurate but that it requires additional time to reach a steady state value.
Model-Based Design Workflows for Cyber-Physical Systems Applied to an Electric-Mechanical Coolant Pump
Authors: Höpfner Gregor , Jacobs Georg , Zerwas Thilo , Drave Imke , Berroth Joerg , Guist Christian , Rumpe Bernhard , Kohl Jens 
Published: March 2021

Abstract
Cyber-Physical Systems (CPS) connect mechanics, electrics and electronics as well as software. Considering the interactions between these domains is a major challenge in product development. Model-Based Systems Engineering (MBSE) enables cross-domain system development, based on commonly understood system architectures. However, there is still a gap in using MBSE for development, especially in mechanics. Systematic evaluation of design decisions based on system architecture models is not done. The strong simulation methods predicting physical product behaviour are not well connected to the evolving system architecture. We propose a new approach for connecting simulation and design models in a System Modelling Language (SysML) system model using the example of a combustion engine’s cooling circuit. The electric-mechanical coolant pump is chosen for design. The design processes of the hydrodynamic pump wheel and the volume flow controller are modelled as workflows in SysML. Here, we integrate design models for the pump wheel and the controller into the workflows. Thereby, parameters of the pump wheel and controller are calculated. Design results are automatically transferred to CAD. A workflow is created, testing the cooling circuit’s behaviour against requirements, combining a Simulink control model and a Simcenter Amesim heat transfer model. The approach results in a framework for automated design and test processes.
Extended Evaluation of Pitting Degradation Tests to Increase the Remaining Useful Life of Gear Wheels
Authors: Gretzinger Yvonne , Kroner Andreas , Henß Mark , Dazer Martin , Bertsche Bernd 
Published: March 2021

Abstract
Within this work, the potential of an operating strategy is analysed based on test runs in laboratory environment, field tests as well as simulations. The operating strategy is used to increase the remaining useful life of gear wheel pitting by reducing the local stress at the weakened tooth. The local stress reduction is achieved by applying an adapted periodic input torque to the transmission and shift the minimum in the area of the weakened tooth. All the other teeth undergo a higher stress and therefore compensate the reduction. To analyse the potential of this strategy, the evaluation of pitting degradation tests has to be extended to all teeth using data from test runs as well as field tests. Both analyses show great potential as many teeth are totally intact. Finally, a simulative approach was carried out to quantify the potential and to show a reference value for the accuracy of the measuring system. As a result, for an increase in lifetime of 10 %, the measurement system has to locate pittings with a size smaller than 1 % based on the total tooth flank. If the pitting is located even earlier, a maximum of 38 % increase in lifetime is possible.
Investigation of lubricant supply in rolling point contacts under starved conditions using CFD simulations
Authors: Fischer D , Goeldel S von , Jacobs G , Stratmann A , König F 
Published: March 2021

Abstract
High friction and wear in rolling bearings are prevented by a lubricating film, which separates the contacting surfaces. In rolling contacts with limited lubricant supply, the film thickness decreases at high rolling speeds, as more lubricant is displaced than replenished. This lubricant depletion is known as starvation and may induce mixed lubrication due to a low film thickness. When estimating the bearing lifetime, a fully flooded lubrication, i.e. an unlimited lubricant supply, is usually assumed. This leads to an overestimation of film thickness in operating ranges where starvation occurs. Thus, considering the onset of starvation is crucial to reduce the risk of premature bearing failures due to high friction and wear in the mixed lubrication regime. Therefore, this contribution presents a method, based on computational fluid dynamics (CFD) simulations, to calculate the onset of starvation in oil lubricated point contacts.