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Calibration of CO and CO₂ Monitors Used in Periodic Inspection of Vehicles at Fixed Stations for Environmental Control

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Green and Sustainable Chemistry 2024年第2期14卷 29-41页

作者： adel Bassuoni Shehata Abdulrahman Rashed Al Askar Najjy Hamad Al Yami Abdullah Suleiman Al Owaysi Sultan K. Alharbi Chemistry Department National Measurement and Calibration Center (NMCC) Saudi Standards Metrology and Quality Organization (SASO) Riyadh Kingdom of Saudi Arabia

Global efforts for environmental cleanliness through the control of gaseous emissions from vehicles are gaining momentum and attracting increasing attention. Calibration plays a crucial role in these efforts by ensuring the quantitative assessment of emissions for informed decisions on environmental treatments. This paper describes a method for the calibration of CO/CO2 monitors used for periodic inspections of vehicles in cites. The calibration was performed in the selected ranges: 900 - 12,000 µmol/mol for CO and 2000 - 20,000 µmol/mol for CO2. The traceability of the measurement results to the SI units was ensured by using certified reference materials from CO/N2 and CO2/N2 primary gas mixtures. The method performance was evaluated by assessing its linearity, accuracy, precision, bias, and uncertainty of the calibration results. The calibration data exhibited a strong linear trend with R² values close to 1, indicating an excellent fit between the measured values and the calibration lines. Precision, expressed as relative standard deviation (%RSD), ranged from 0.48 to 4.56% for CO and from 0.97 to 3.53% for CO2, staying well below the 5% threshold for reporting results at a 95% confidence level. Accuracy measured as percent recovery, was consistently high (≥ 99.1%) for CO and ranged from 84.90% to 101.54% across the calibration range for CO2. In addition, the method exhibited minimal bias for both CO and CO2 calibrations and thus provided a reliable and accurate approach for calibrating CO/CO2 monitors used in vehicle inspections. Thus, it ensures the effectiveness of exhaust emission control for better environment.

关键词： Monitors Periodic Inspection CO/CO2 Calibration Linearity Precision Accuracy

Potential Benefits and Obstacles of the Use of Internet of Things in Saudi Universities: Empirical Study

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Advances in Internet of Things 2024年第1期14卷 1-20页

作者： Najmah adel Fallatah Fahad Mahmoud Ghabban Omair Ameerbakhsh Ibrahim Alfadli Wael Ghazy Alheadary Salem Sulaiman Alatawi Ashwaq Hasen Al-Shehri College of Computer Science and Engineering Taibah University Madinah Saudi Arabia Ministry of Education in Al-Madinah Al-Munawwarah Region Madinah Saudi Arabia

Internet of Things (IoT) among of all the technology revolutions has been considered the next evolution of the internet. IoT has become a far more popular area in the computing world. IoT combined a huge number of things (devices) that can be connected through the internet. The purpose: this paper aims to explore the concept of the Internet of Things (IoT) generally and outline the main definitions of IoT. The paper also aims to examine and discuss the obstacles and potential benefits of IoT in Saudi universities. Methodology: the researchers reviewed the previous literature and focused on several databases to use the recent studies and research related to the IoT. Then, the researchers also used quantitative methodology to examine the factors affecting the obstacles and potential benefits of IoT. The data were collected by using a questionnaire distributed online among academic staff and a total of 150 participants completed the survey. Finding: the result of this study reveals there are twelve factors that affect the potential benefits of using IoT such as reducing human errors, increasing business income and worker’s productivity. It also shows the eighteen factors which affect obstacles the IoT use, for example sensors’ cost, data privacy, and data security. These factors have the most influence on using IoT in Saudi universities.

关键词： Internet of Things (IoT) M2M Factors Obstacles Potential Benefits Universities

Planning Target Volume Margin in Linac-Based Stereotactic Radiosurgery for Brain Metastases

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Journal of Cancer Therapy 2024年第7期15卷 265-272页

作者： Hany S. Attallah Radwa M. Hamed Khaled M. EL-Shahat Aliaa Mahmoud Mahmoud Abdallah Ibraheem Haggag Emad Moustafa adel Yassin Department of Radiation Oncology International Medical Center (IMC) Cairo Egypt Department of Radiation Oncology Armed Forces Medical Collogue (AFCM) Cairo Egypt Department of Medical Physics Al Azhar University Cairo Egypt Department of Medical Physics International Medical Center (IMC) Cairo Egypt Department of Medical Physics Department of Clinical Oncology Faculty of Medicine Zagazig University Zagazig Egypt

Background: The treatment of brain metastases with radiotherapy has shifted to the use of Stereotactic Radio-surgery (SRS). The technical issue of expanding the treatment volume around the Gross Tumor Volume (GTV) is a current debate. Radiotherapy centers use variable GTV-PTV margins, ranging from one to 2 mm. Material and Methods: We performed a dosimetric comparison in plans of twenty patients using three margins: PTV zero, PTV1, and PTV2. We also developed imaginary Peel volumes. These volumes are described as follows: Peel1 = PTV1 − GTV, Peel2 = PTV2 − GTV. Results: Our results showed that the mean PTV volume differed significantly across the different margins (p = 0.000). The V12 of the brain significantly varied as a function of PTV margin (p = 0.000). The target coverage and plan quality indices were not significantly different. The Peel volume dosimetric analysis showed that the mean dose was significantly higher in the nearby normal brain tissue: Peel1 (p = 0.022) and Peel 2 (p = 0.013). Conclusion: According to our dosimetric analysis, expanding the GTV into a PTV by 1 mm margin is more convenient than 2 mm.

关键词： SRS Brain Metastases PTV

Integration of automatic voltage regulator and power system stabilizer: small-signal stability in DFIG-based wind farms

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Journal of Modern Power Systems and Clean Energy 2019年第5期7卷 1115-1128页

作者： Sirine ESSALLAH adel BOUALLEGUE adel KHEDHER Universite de Sousse Ecole Nationale d’Ingenieurs de SousseLATIS-Laboratory of Advanced Technology and Intelligent Systems4023 SousseTunisia

The increasing penetration of wind farms in the energy sector directly affects the dynamic behavior of the power *** increasing use of wind energy in the power system worsens its stability and inherently influences the firmness of a small *** investigate these effects,one of the synchronous generators(SGs)of the grid is considered defective and is replaced by a doubly fed induction generator(DFIG)-based wind farm of the same *** small-signal stability of a power system is usually evaluated via eigenvalue analysis where local-area and inter-area oscillatory modes for the New England test system are *** controls,such as automatic voltage regulator(AVR)and power system stabilizer(PSS),are added to attenuate the generated *** this study,the impact of wind energy on the small-signal stability of the power system is *** combinations of AVR and PSS types are considered to mitigate the undesirable alterations.A comparative study is performed based on numerical simulations to choose the best combination of AVR and PSS *** obtained results prove that the proposed combination yields good results in terms of stability enhancement both under normal operating conditions and in DFIG-based wind farms.

关键词： Power system stability Power transmission system Transient analysis Voltage regulation

Validation of a Method for Characterization of Ethanol in Water by HS-GC-FID to Serve the Traceability of Halal Measurements

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Green and Sustainable Chemistry 2024年第2期14卷 17-28页

作者： adel B. Shehata Abdulrahman R. Al Askar Mohammed A. Al Rasheed Abdulrahman M. Al Zahrany Fahd A. Al Kharraa Sowailem A. Al Sowailem Chemistry Department/National Measurement and Calibration Center (NMCC) Saudi Standards Metrology and Quality Organization (SASO) Riyadh Kingdom of Saudi Arabia

The determination of the ethanol content in food products is of fundamental importance for HALAL certification. In this work, an analytical method for the determination of ethanol in water by headspace gas chromatography with flame ionization detector (HS-GC-FID) has been developed and validated for the use in characterization of ethanol reference materials. The validation study was carried out in the linear calibration range 100 - 1500 mg/kg using the NIST SRM 2900, nominal 95.6%. The studied performance characteristics of the method were the limit of detection, LOD, the limit of quantification LOQ, selectivity, linearity, precision, recovery and bias. The validation results showed that the method is selective, precise, accurate and free from any significant bias. The LOD and LOQ were 1.27 and 3.86 mg/kg respectively and the estimated expanded uncertainty was 2% indicating that the method is fit for the purpose of certification of ethanol in water reference materials.

关键词： Ethanol HS-GC-FID Validation Linearity Precision Bias

Enhancing Thermal Performance of a Parabolic Trough Collector with Inserting Longitudinal Fins in the Down Half of the Receiver Tube

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Journal of Thermal Science 2020年第5期29卷 1309-1321页

作者： LAARABA adel MEBARKI Ghazali Department of physics University of BatnalBatna 05000Algeria Faculty of Technology LESEI LaboratoryDepartment of Mechanical EngineeringUniversity of Batna2Batna 05000Algeria

Heat transfer in a finned absorber of a parabolic trough collector was studied numerically. The main aim of this work was to study the effect of attached fins on the enhancement of the thermal performance of a parabolic trough collector. The values of the fin's length varied from 0 to 20 mm;their thicknesses varied from 0 to 8 mm and their number was 5. The parameters used in the current study are: the thermal and dynamic field,friction coefficient, Nusselt number, the thermal efficiency and thermal enhancement index. Obtained results show that inclusion of fins to the lower half of the absorber tube can enhance the heat transfer between the absorber tube and working fluid. The increase of the fin*s length increases the friction factor, Nusselt number and thermal efficiency, and the increase of fin's thickness also increases the previous parameters. Starting the value 6 mm of thickness, its effect remains the same, but thickness is less effective than length. The values 15 mm of length and 6 mm of thickness are selected as optimal values. Results show that the inclusion of the fins enhances the thermal performance of the parabolic collector by 8.45%.

关键词： solar energy Nusselt number thermal efficiency parabolic trough collector forced convection

Anomaly Classification Using Genetic Algorithm-Based Random Forest Modelfor Network Attack Detection

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Computers, Materials & Continua 2021年第1期66卷 767-778页

作者： adel Assiri Management Information Systems Department College of BusinessKing Khalid UniversityAbha61421Saudi Arabia

Anomaly classification based on network traffic features is an important task to monitor and detect network intrusion ***-based intrusion detection systems(NIDSs)using machine learning(ML)methods are effective tools for protecting network infrastructures and services from unpredictable and unseen *** several ML methods,random forest(RF)is a robust method that can be used in ML-based network intrusion detection ***,the minimum number of instances for each split and the number of trees in the forest are two key parameters of RF that can affect classification ***,optimal parameter selection is a real problem in RF-based anomaly classification of intrusion detection *** this paper,we propose to use the genetic algorithm(GA)for selecting the appropriate values of these two parameters,optimizing the RF classifier and improving the classification accuracy of normal and abnormal network *** validate the proposed GA-based RF model,a number of experiments is conducted on two public datasets and evaluated using a set of performance evaluation *** these experiments,the accuracy result is compared with the accuracies of baseline ML classifiers in the recent *** results reveal that the proposed model can avert the uncertainty in selection the values of RF’s parameters,improving the accuracy of anomaly classification in NIDSs without incurring excessive time.

关键词： Network-based intrusion detection system(NIDS) random forest classifier genetic algorithm KDD99 UNSW-NB15

Mesoporous WO_3-graphene photocatalyst for photocatalytic degradation of Methylene Blue dye under visible light illumination

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Journal of Environmental Sciences 2018年第4期30卷 328-337页

作者： adel A.Ismail M.Faisal adel Al-Haddad Wastewater Treatment and Reclamation Technologies (WTRT) Water Research Center Kuwait Institute for Scientific Research Advanced Materials and Nano-Research Centre Najran University

Advanced oxidation technologies are a friendly environmental approach for the remediation of industrial wastewaters. Here, one pot synthesis of mesoporous WO3 and WO3-graphene oxide（GO） nanocomposites has been performed through the sol–gel method. Then, platinum（Pt） nanoparticles were deposited onto the WO3 and WO3-GO nanocomposite through photochemical reduction to produce mesoporous Pt/WO3 and Pt/WO3-GO nanocomposites. X-ray diffraction（XRD） findings exhibit a formation of monoclinic and triclinic WO3 phases. Transmission Electron Microscope（TEM） images of Pt/WO3-GO nanocomposites exhibited that WO3 nanoparticles are obviously agglomerated and the particle sizes of Pt and WO3 are ~ 10 nm and 20–50 nm, respectively. The mesoporous Pt/WO3 and Pt/WO3-GO nanocomposites were assessed for photocatalytic degradation of Methylene Blue（MB） as a probe molecule under visible light *** findings showed that mesoporous Pt/WO3, WO3-GO and Pt/WO3-GO nanocomposites exhibited much higher photocatalytic efficiencies than the pure WO3. The photodegradation rates by mesoporous Pt/WO3-GO nanocomposites are 3, 2 and 1.15 times greater than those by mesoporous WO3, WO3-GO, and Pt/WO3, respectively. The key factors of the enhanced photocatalytic performance of Pt/WO3-GO nanocomposites could be explained by the highly freedom electron transfer through the synergetic effect between WO3 and GO sheets, in addition to the Pt nanoparticles that act as active sites for O2 reduction, which suppresses the electron hole pair recombination in the Pt/WO3-GO nanocomposites.

关键词： Mesoporous Pt/WO3 nanocomposites Graphene oxide Methylene Blue photodegradation Visible light

Characterization of component interactions in two-stage axial turbine

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Chinese Journal of Aeronautics 2016年第4期29卷 893-913页

作者： adel Ghenaiet Kaddour Touil Laboratory of Energetics and Conversion Systems Faculty of Mechanical Engineering University of Sciences and Technology Houari Boumediene Laboratory of Thermal Power Systems Applied Mechanics

This study concerns the characterization of both the steady and unsteady flows and the analysis of stator/rotor interactions of a two-stage axial turbine. The predicted aerodynamic performances show noticeable differences when simulating the turbine stages simultaneously or separately. By considering the multi-blade per row and the scaling technique, the Computational fluid dynamics(CFD) produced better results concerning the effect of pitchwise positions between vanes and blades. The recorded pressure fluctuations exhibit a high unsteadiness characterized by a space–time periodicity described by a double Fourier decomposition. The Fast Fourier Transform FFT analysis of the static pressure fluctuations recorded at different interfaces reveals the existence of principal harmonics and their multiples, and each lobed structure of pressure wave corresponds to the number of vane/blade count. The potential effect is seen to propagate both upstream and downstream of each blade row and becomes accentuated at low mass flow rates. Between vanes and blades, the potential effect is seen to dominate the quasi totality of blade span, while downstream the blades this effect seems to dominate from hub to mid span. Near the shroud the prevailing effect is rather linked to the blade tip flow structure.

关键词： CFD FFT analysis Pressure fluctuations Two-stage axial turbine Unsteady flows Vane/blade interactions