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Flag-Based Vehicular Clustering Scheme for Vehicular Ad-Hoc Networks

Computers, Materials & Continua 2023年第12期77卷 2715-2734页

作者： Fady Samann Shavan Askar Department of Energy engineering Technical College of EngineeringDuhok Polytechnic UniversityDuhok42001Iraq Department of Information System engineering Technical College of EngineeringErbil Polytechnic UniversityErbil44001Iraq

Clustering schemes in vehicular networks organize vehicles into logical groups.They are vital for improving network performance,accessing the medium,and enabling efficient data dissemination.Most schemes rely on periodically broadcast hello messages to provide up-to-date information about the vehicles.However,the periodic exchange of messages overwhelms the system and reduces efficiency.This paper proposes the Flag-based Vehicular Clustering(FVC)scheme.The scheme leverages a combination of Fitness Score(FS),Link Expiration Time(LET),and clustering status flags to enable efficient cluster formation in a hybrid manner.The FVC relies on the periodic broadcast of the basic safety message in the Dedicated Short-Range Communications(DSRC)standard for exchanging the vehicle’s status,FS,and joining request.Piggybacking extra information onto the existing periodic beacon reduces the overhead of exchanging additional control messages,which is the main contribution of this work.The scheme is implemented in a hybrid manner by utilizing a Road Side Unit(RSU)to implement a clustering algorithm.This work considered the FastPAM algorithm,a fast version of the Partitioning Around Medoids(PAM)clustering algorithm,to generate a list of potential cluster heads.The FVC scheme uses the LET as the clustering metric with the FastPAM algorithm.Moreover,the Lightweight FastPAM Vehicular Clustering(LFPVC)algorithm is considered by selecting the initial cluster heads based on the FS instead of the greedy FastPAM’s build stage.In the absence of the RSU,the vehicles utilize the FS with proper back-off time to self-elect the cluster head.The hybrid FVC scheme increased the cluster lifetime by 32%and reduced the control-message overhead by 63%compared to the related work.Moreover,the LFPVC algorithm achieved similar results to the FastPAM algorithm.

关键词： Clustering scheme VANET FastPAM

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Fast adaptive regression-based model predictive control

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Control Theory and Technology 2023年第4期21卷 555-570页

作者： Eslam Mostafa Hussein A.Aly Ahmed Elliethy Electrical and Computer engineering Military Technical CollegeCairo14627Egypt

Model predictive control(MPC)is an optimal control method that predicts the future states of the system being controlled and estimates the optimal control inputs that drive the predicted states to the required reference.The computations of the MPC are performed at pre-determined sample instances over a finite time horizon.The number of sample instances and the horizon length determine the performance of the MPC and its computational cost.A long horizon with a large sample count allows the MPC to better estimate the inputs when the states have rapid changes over time,which results in better performance but at the expense of high computational cost.However,this long horizon is not always necessary,especially for slowly-varying states.In this case,a short horizon with less sample count is preferable as the same MPC performance can be obtained but at a fraction of the computational cost.In this paper,we propose an adaptive regression-based MPC that predicts the best minimum horizon length and the sample count from several features extracted from the time-varying changes of the states.The proposed technique builds a synthetic dataset using the system model and utilizes the dataset to train a support vector regressor that performs the prediction.The proposed technique is experimentally compared with several state-of-the-art techniques on both linear and non-linear models.The proposed technique shows a superior reduction in computational time with a reduction of about 35–65%compared with the other techniques without introducing a noticeable loss in performance.

关键词： Regression analysis MPC Control Parametrization Wavelet Support vector regression(SVR) Optimization

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Internet of Things (IoT) Security Enhancement Using XGboost Machine Learning Techniques

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Computers, Materials & Continua 2023年第10期77卷 717-732页

作者： Dana F.Doghramachi Siddeeq Y.Ameen Department of Information Systems engineering Techniques Erbil Technical Engineering CollegeErbil Polytechnic UniversityErbil44001Iraq Department of Energy engineering Technical College of EngineeringDuhok Polytechnic UniversityDuhok42001Iraq

The rapid adoption of the Internet of Things(IoT)across industries has revolutionized daily life by providing essential services and leisure activities.However,the inadequate software protection in IoT devices exposes them to cyberattacks with severe consequences.Intrusion Detection Systems(IDS)are vital in mitigating these risks by detecting abnormal network behavior and monitoring safe network traffic.The security research community has shown particular interest in leveraging Machine Learning(ML)approaches to develop practical IDS applications for general cyber networks and IoT environments.However,most available datasets related to Industrial IoT suffer from imbalanced class distributions.This study proposes a methodology that involves dataset preprocessing,including data cleaning,encoding,and normalization.The class imbalance is addressed by employing the Synthetic Minority Oversampling Technique(SMOTE)and performing feature reduction using correlation analysis.Multiple ML classifiers,including Logistic Regression,multi-layer perceptron,Decision Trees,Random Forest,and XGBoost,are employed to model IoT attacks.The effectiveness and robustness of the proposed method evaluate using the IoTID20 dataset,which represents current imbalanced IoT scenarios.The results highlight that the XGBoost model,integrated with SMOTE,achieves outstanding attack detection accuracy of 0.99 in binary classification,0.99 in multi-class classification,and 0.81 in multiple sub-classifications.These findings demonstrate our approach’s significant improvements to attack detection in imbalanced IoT datasets,establishing its superiority over existing IDS frameworks.

关键词： IoT detection system machine learning SMOTE XGboost

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Chemical stability, thermal behavior, and shelf life assessment of extruded modified double-base propellants

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Defence Technology（防务技术） 2018年第1期14卷 70-76页

作者： Sherif Elbasuney Ahmed Fahd Hosam E.Mostafa Sherif F.Mostafa Ramy Sadek School of Chemical engineering Military Technical College

Double base propellant suffers from lack of chemical stability; this could result in self ignition during storing. Modified double base(MDB) propellant based on stoichiometric binary mixture of oxidizermetal fuel(Ammonium perchlorate/Aluminum), and energetic nitramines(HMX) offered enhanced thrust as well as combustion characteristics. This study is devoted to evaluate the impact of such energetic additives on thermal behavior, chemical stability, and shelf life. Extruded MDB formulations were manufactured by extrusion process. Artificial aging at 80℃ for 28 days was conducted. Shelf life assessment was performed using Van't Hoff's equation. Quantification of evolved NOxgases with aging time was performed using quantitative stability tests. MDB formulation based on HMX demonstrated extended service life of 16 years compared with(AP/Al)-MDB which demonstrated 9 years. This finding was ascribed to the reactivity of AP with nitroglycerin with the formation of perchloric acid. Thermal behavior of aged MDB, exhibited an increase in heat released with time; this was ascribed to the autocatalytic thermal degradation during artificial aging. The increase in released heat by 31% was found to be equivalent to evolved NOx gases of 6.2 cm^3/5 g and 2.5 cm^3/1 g for Bergmann-Junk test, and Vacuum stability test respectively. This manuscript shaded the light on a novel approach to quantify evolved NOx gases to heat released with aging time. MDB based on HMX offered balanced ballistic performance,chemical stability, and service life.

关键词： Double-base Chemical stability Thermal behavior Artificial aging Shelf life assessment

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Multiple Phase Change Materials for Performance Enhancement of a Solar Dryer with Double Pass Collector

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Energy engineering 2021年第5期118卷 1483-1497页

作者： Ahmed J.Hamad Fawziea M.Hussien Johain J.Faraj engineering technical college Middle Technical UniversityBaghdadIraq

The fluctuation in drying temperature influences the food products’quality and drying time significantly during the drying process using an indirect solar dryer.One of the effective methods to reduce these variations in the temperature is based on thermal storage materials to control the drying temperature.An experimental investigation is presented in this study to evaluate the performance of an indirect solar dryer with air double pass using multiple phase change materials(PCM)as thermal storage materials.Two PCMs with different melting points are used to store the available heat energy during peak sunshine periods and reduce the drying temperature fluctuations.Drying tests on a food product sample are conducted in three cases,the first was without PCMs using natural convection.The second and third cases are based on forced convection with and without using multiple PCMs under Baghdad city conditions.The results showed that;approximately a steady temperature of hot drying air was obtained during relatively low ambient temperatures when the dryer was incorporated with multiple PCMs.The drying time of the product sample for the natural,forced convection without PCMs and forced with PCMs was 87,72 and 47 h,respectively.The higher performance of the dryer was for the forced convection with PCMs.The reduction percentage in drying time was about 17.2%and 46%for the forced convection without and with PCMs respectively compared with natural convection.The average drying rate for the natural,forced without PCMs and forced convection with PCMs was 0.0093,0.0135 and 0.0172 kg/h,respectively.The enhancement in thermal efficiency of the solar collector and drying chamber with multiple PCMs was 43%and 25.5%,respectively,compared with a typical solar dryer.

关键词： Solar dryer double pass indirect dryer multiple PCM drying rate

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Molecular and nanostructure designed superhydrophilic material with unprecedented antioil-fouling property for diverse oil/water separation

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Science China(Technological Sciences) 2022年第6期65卷 1273-1282页

作者： WANG ZheCun GUAN Min YANG Xin LI HanZhen WANG LaiGui college of Materials Science and engineering Liaoning Technical UniversityFuxin 123000China School of Mechanics and engineering Liaoning Technical UniversityFuxin 123000China

The design and development of new advanced superwetting porous membranes with antioil-fouling performance are still rare and highly desirable because of their potential widespread applications.A metallic phosphate nanoflower-covered mesh membrane with superhydrophilic and unprecedented antioil-fouling properties is prepared by an exceptionally simple and effective in-situ solution corrosion method.As demonstrated,the outstanding antioil-fouling property of the resulting mesh membrane is connected with the special phosphate group and the three-dimensional(3 D) nanoflower structure.Owing to the antioil-fouling property,upon to water,the oil-fouled mesh membrane can keep the surface free of various kinds of oils,including viscous crude oil to light n-hexane.Thanks to its unprecedented self-cleaning property,the superhydrophilic mesh membrane can effectively separate different oil/water mixtures without prior wetted by water,exhibiting great potential for practical spilled oil remediation.

关键词： crude oil/water separation inorganic membrane antioil-fouling property metallic phosphate nanoflowers oil spill remediation

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Novel colored flames via chromaticity of essential colors

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Defence Technology（防务技术） 2019年第2期15卷 210-215页

作者： Ramy Sadek Mohamed Kassem Mohamed Abdo Ahmed Fahd Hesham Tantawy Amir Elsaidy Sherif Elbasuney School of Chemical engineering Military Technical College

Colored flame compositions have distinctive variety of applications ranging from military signaling,rocket tracking, and illuminating devices. Certain elements and compounds when heated to high temperature are able to emit unique wavelengths in the visible region. This study, reports on the development of novel colored flames that cannot be generated by emitting atomic/molecular species. This was achieved by using chromaticity of basic colored flames. Mixing of high quality primary colored flames including Blue, Yellow, and Red in proper ratio was conducted; any interfering incandescent emission resulted from MgO was eliminated using Al metal fuel. The spectral characteristics in terms of luminous intensity, and color quality were evaluated using digital luxmeter and UV-Vis. spectrometer respectively.High quality mixed colored flames include violet, sweet pink, and marigold were developed. This study shaded the light on the state of the art for the real development of novel colored flame compositions and chromaticity of basic colored flames.

关键词： Pyrotechnics Colored flame Atomic spectroscopy Molecular spectroscopy Luminous intensity Color quality Chromaticity

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New Zircon U-Pb Ages of Granitic Rocks in Northeastern Jiagedaqi of the Da Hinggan Mountains and their Significance

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Acta Geologica Sinica(English Edition) 2018年第4期92卷 1656-1658页

作者： YIN Zhigang LI Haina HAO Ke GONG Zhaomin PANG Xuechang LI Min ZHANG Shengting college of Mining engineering Liaoning Technical University

Objective The research area is located in the north of the Xing＇an block and within the Ali River-Zhalantun granite belt in the eastern part of the Xingmeng orogenic belt. The geotectonic setting and geological evolution history of this area are complex with strong magmatic activity and extremely developed granite rocks. Since predecessors have not obtained accurate dating result, there is much controversy over the formation of granitic rocks. Therefore, this work conducted zircon U-Ph dating on alkali-feldspar granite and granite porphyry in the northeast of Jiagedaqi to provide age constraint. The age data shows that the forming age is the Early Cretaceous and provides age basis for the tectonic evolution of the Da Hinggan Mountains.

关键词： Pb Th New Zircon U-Pb Ages of Granitic Rocks in Northeastern Jiagedaqi of the Da Hinggan Mountains and their Significance

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Continuous hydrothermal synthesis of AlO(OH)nanorods as a clean flame retardant agent

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Particuology 2015年第5期13卷 66-71页

作者： Sherif Elbasuney School of Chemical engineering Military Technical College

Aluminum-oxide-hydroxide （AIOOH） is a clean and non-toxic flame retardant. There have been many trials for the fabrication of ultrafine AIOOH, Two main approaches exist for nano-AlOOH synthesis： reactive precipitation and batch hydrothermal synthesis, Both approaches are laborious and time consuming with poor control of particle morphology. We report on the novel continuous flow manufacture of AIOOH nanorods with controlled morphology （particle size and shape） by hydrothermal synthesis. AIOOH was harvested from its mother liquor （colloidal solution） using poly（acrylamide-co-acrylic acid） copolymer as a flocculating agent. The developed AIOOH shape and size, crystalline phase, thermal stability, and endothermic heat sink action were investigated by transmission electron microscopy, X-ray diffractome- try, thermogravimetric analysis, and differential scanning calorimetry, respectively. The phase transition of AlOOH to Al2O3 was demonstrated by conducting different X-ray diffractometry scans from 400 to 700℃. These results may provide an option for the continuous synthesis of nano-AIOOH as a clean and non-toxic flame retardant with excellent thermal stability. Consequently, enhanced flammability properties can be achieved at low solids loading.

关键词： Flame retardants Hydrated minerals Hydrothermal synthesis

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Synthesis and surface modification of nanophosphorous-based flame retardant agent by continuous flow hydrothermal synthesis

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Particuology 2015年第5期13卷 82-88页

作者： Sherif Elbasuney Hosam E.Mostafa School of Chemical engineering Military Technical College

Nanoparticles can provide flame retardance to hosting polymers and act as nano fire extinguishers. Hydroxyapatite （Ca5（OH）（PO4）3）（HA） is not hygroscopic, and is thermally stable up to 800℃, with 18.5 wt% phosphorous content. It is this high phosphorous content that can provide HA with flame retardant properties. In this paper, we report on the continuous synthesis of ultrafine HA using a hydrothermal synthesis technique. The HA surface properties were changed from hydrophilic to hydrophobic by post-synthesis surface modification. The ratio of the HA nanoparticles and an intumescent agent known as Exolit AP750 was investigated to yield a self-extinguishing multi-component epoxy nanocomposite for extended application under extreme fire conditions. The HA/AP750/epoxy nanocomposite was able to resist a flame at 1700 oc and self-extinguish after the flame had been removed. The nanocomposite showed an enhanced flammability performance in standard cone calorimetry testing and formed a compact and cohesive protective char layer with a 50% decrease in peak heat released compared with virgin epoxy. Our aim was to establish the use of HA as an effective nanofiller with phosphorous-based flame retardant properties. The surface of this nano fire extinguisher was modified effectively with different surfactants for enhanced compatibility with different polymeric matrices.

关键词： Flame retardancy Phosphorous-based agent Nanocomposites Hydrothermal synthesis Hydroxyapatite

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