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An Optimization Approach of IoD Deployment for Optimal Coverage Based on Radio Frequency Model

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Computer Modeling in Engineering & Sciences 2024年第6期139卷 2627-2647页

作者： Tarek Sheltami Gamil Ahmed Ansar yasar Computer Engineering Department Interdisciplinary Research Center of Smart Mobility and LogisticsKing Fahd University of Petroleum and MineralsDhahran31261Saudi Arabia Transportation Research Institute(IMOB) Hasselt UniversityHasselt3500Belgium

Recently,Internet of Drones(IoD)has garnered significant attention due to its widespread applications.However,deploying IoD for area coverage poses numerous limitations and challenges.These include interference between neighboring drones,the need for directional antennas,and altitude restrictions for drones.These challenges necessitate the development of efficient solutions.This research paper presents a cooperative decision-making approach for an efficient IoDdeployment to address these challenges effectively.The primary objective of this study is to achieve an efficient IoDdeployment strategy thatmaximizes the coverage regionwhile minimizing interference between neighboring drones.In deployment problem,the interference increases as the number of deployed drones increases,resulting in bad quality of communication.On the other hand,deploying a few drones cannot satisfy the coverage demand.To accomplish this,an enhanced version of a concise population-based meta-heuristic algorithm,namely Improved Particle SwarmOptimization(IPSO),is applied.The objective function of IPSO is defined based on the coverage probability,which is primarily influenced by the characteristics of the antennas and drone altitude.A radio frequency(RF)model is derived to evaluate the coverage quality,considering both Line of Sight(LOS)and Non-Line of Sight(NLOS)down-link coverage probabilities for ground communication.It is assumed that each drone is equipped with a directional antenna to optimize coverage in a given region.Extensive simulations are conducted to assess the effectiveness of the proposed approach.Results demonstrate that the proposed method achieves maximum coverage with minimum transmission power.Furthermore,a comparison is made against Collaborative Visual Area Coverage Approach(CVACA),and a game-based approach in terms of coverage quality and convergence speed.The simulation results reveal that our approach outperforms both CVACA and the gamebased schemes in terms of coverage and convergence speed.Comparisons validate the sup

关键词： IoD line of sight optimal deployment IPSO RF model

The Association between Serum Resistin Levels and Major Adverse Cardiac Events

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World Journal of Cardiovascular Diseases 2017年第10期7卷 332-339页

作者： Umit yasar sinan Ozge Cetinarslan Veysel Oktay Ilknur Calpar Yalcin Dalgic Aysem Kaya Alev Arat Ozkan Murat K. Ersanli Department of Cardiology Istanbul University Institute of Cardiology Istanbul Turkey Department of Biochemistry Istanbul University Institute of Cardiology Istanbul Turkey

Resistin is a member of the family of cysteine-rich secretary proteins called resistin-like molecules (RELMs). It is suggested to be involved in inflammatory conditions and atherosclerosis. We have established a significant correlation between serum resistin levels and coronary artery disease (CAD) in a study was performed between 2011 and 2012 in our institute in two hundred fourteen patients (164 CAD patients and 50 controls). Then the CAD patients were followed up to investigate the relationship between increased serum resistin levels and major adverse cardiac events (MACE) between 2012 and 2016. One hundred fifty-five of 164 patients (95%) were followed up and 9 patients lost to follow up. There were 39 MACE (25%) in four years of follow-up.?There were 16 in-hospital deaths due to cardiac causes, 8 revascularization procedures, and 15 re-hospitalization due to acute coronary syndrome (ACS) or heart failure (HF). The patients with MACE had similar serum resistin level (median: 71.37 pg/ml) compared to patients without MACE (median: 80.23 pg/ml) (p > 0.05).

关键词： Resistin Adipokine Atherosclerosis Coronary Artery Disease Major Adverse Cardiac Event

Network pharmacology and computational analysis of berberine and kuwanon Z as possible natural antiviral compounds in COVID-19

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Pharmacology Discovery

Pharmacology Discovery 2024年第1期4卷 31-43页

作者： Ansari Vikhar Danish Ahmad Qazi yasar Subur W Khan Syed Ayaz Ali Ansari Altamash Mohd Mukhtar Khan Nikhil S Sakle y.2.chavan college of pharmacy dr.babasaheb ambedkar marathwada universityaurangabad 431001india

Background:Global efforts to discover effective therapeutic agents for combating coronavirus disease 19(COVID-19)have intensified the exploration of natural compounds with potential antiviral properties.In this study,we utilized network pharmacology and computational analysis to investigate the antiviral effects of Berberine and Kuwanon Z against severe acute respiratory syndrome coronavirus 2,the viruses responsible for COVID-19.Method:Utilizing comprehensive network pharmacology approaches,we elucidated the complex interactions between these compounds and the host biological system,highlighting their multitarget mechanisms.Network pharmacology identifies COVID-19 targets and compounds through integrated protein‒protein interaction and KEGG pathway analyses.Molecular docking simulation studies were performed to assess the binding affinities and structural interactions of Berberine and Kuwanon Z with key viral proteins,shedding light on their potential inhibitory effects on viral replication and entry.Results:Network-based analyses revealed the modulation of crucial pathways involved in the host antiviral response.Compound-target network analysis revealed complex interactions(122 nodes,121 edges),with significant interactions and an average node degree of 1.37.KEGG analysis revealed pathways such as the COVID-19 pathway,chemokines and Jak-sat in COVID-19.Docking studies revealed that Kuwanon Z had binding energies of-10.5 kcal/mol for JAK2 and-8.1 kcal/mol for the main protease.Conclusion:The findings of this study contribute to the understanding of the pharmacological actions of Berberine and Kuwanon Z in the context of COVID-19,providing a basis for further experimental validation.These natural compounds exhibit promise as potential antiviral agents,offering a foundation for the development of novel therapeutic strategies in the ongoing battle against the global pandemic.

关键词： COVID-19 kuwanon Z berberine network pharmacology SARS-CoV-2 molecular docking

Unraveling the therapeutic mechanisms of myristic acid and luteolin 7-rutinoside in oral cancer: insights from network pharmacology and molecular docking analysis

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Pharmacology Discovery

Pharmacology Discovery 2024年第2期4卷 1-9页

作者： Ansari Vikhar Danish Ahmad Misba Ruhi Syed Ayaz Ali Qazi yasar Mohd.Mukhtar Khan Subur W Khan Mohammed Imran Anees Y.B.Chavan College of Pharmacy Dr.Babasaheb Ambedkar Marathwada UniversityAurangabad 431001India Maulana Azad College Dr.Babasaheb Ambedkar Marathwada UniversityAurangabad 431001India

Background:The compound Luteolin-7-rutinoside(L7R)is a flavone derivative of luteolin,predominantly identified in plant species belonging to the families Asteraceae.Conversely,Myristic acid is characterized by its structure as a 14-carbon,unsaturated fatty acid.In this investigation,we endeavor to elucidate the putative mechanisms underlying the therapeutic effects of Myristic Acid and Luteolin 7-rutinoside in the context of oral cancer treatment,employing network pharmacology coupled with molecular docking methodologies.Methods:The protein targets of Myristic Acid and Luteolin 7-rutinoside were identified through a search on the Swiss Target Database.Subsequently,a compound-target network was constructed using Cytoscape 3.9.1.Targets associated with OC were retrieved from the OMIM and GeneCards databases.The overlap between compound targets and OC-related targets was determined,and the resulting shared targets were subjected to protein-protein interaction(PPI)network analysis using the STRING database.Additionally,gene ontology(GO)and Kyoto Encyclopedia of Genes and Genomes(KEGG)enrichment analyses were conducted on the identified targets.Molecular docking were performed to investigate the interactions between the core target and the active compound.Results:The component target network comprises 103 nodes and 102 edges.Among the proteins in the protein-protein interaction(PPI)network,those with higher degrees are TNF,PPARG,and TP53.Analysis through Gene Ontology(GO)and Kyoto Encyclopedia of Genes and Genomes(KEGG)pathways indicates that the treatment of OC with Myristic Acid and Luteolin 7-rutinoside primarily involves the regulation of miRNA transcription and inflammatory response.The identified signaling pathways include Pathways in cancer,PPAR signaling pathway,EGFR signaling pathway,and TNF signaling pathway.Molecular docking studies reveal that Luteolin 7-rutinoside and Myristic acid exhibit higher affinity towards TNF,PPARG,TP53,and EGFR.Conclusion:This study reveals the potential molecular mechanism of My

关键词： myristic acid luteolin 7-rutinoside network pharmacology oral cancer molecular docking

SubStop:An analysis on subscription email bombing attack and machine learning based mitigation

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High-Confidence Computing

High-Confidence Computing 2022年第4期2卷 37-51页

作者： Aurobinda Laha Md Tahmid yasar Yu Cheng Big River Steel LLC 2027 E.State Hwy 198Osceola72370ArkansasUSA Illinois Institute of Technology 3301 S.Dearborn St.Chicago60616IllinoisUSA

Email Bombing,a kind of denial-of-service(DoS)attack is crippling internet users and is on the rise recently.A particularly notorious type is the Subscription Bombing attack,where a victim user’s inbox is bombarded with a stream of subscription emails at a particular period.This kind of attack helps the perpetrator to hide their real motive in lieu of a barrage of legitimate-looking emails.The main challenge for detecting subscription bombing attacks is that most of the attacking email appears to be legitimate and benign and thus can bypass existing anti-spam filters.In order to shed some light on the direction of detecting the bombing attacks,in this paper we first conduct some reverse engineering study on the Gmail anti-spam mechanism(as the information is not publicly available)and in-depth feature analysis of real-life bombing attack emails.Leveraging the insights from our reverse engineering study and data analysis,we propose a novel layered detection architecture,termed as SubStop,to detect and mitigate subscription bombs.SubStop exploits the statistics of incoming volume,source domain distribution,the correlation among different features,and implements machine learning to achieve effective detection.In specific,we utilize the weighted support vector machine(WSVM)and properly tune the class weights to achieve high accuracy in detecting bombing attacks.Despite the scarcity of public email data sets,we conduct extensive experiments on a real-life subscription bomb attack and real-time attacks using our bombing simulation script(which is facilitated by our reverse engineering findings),on test email accounts.Detailed experimental results show that our proposed architecture is very robust and highly accurate in detecting and mitigating a subscription bombing attack.

关键词： Email bombing Subscription Reverse engineering Support vector machine

STEM Education as a Concept Borrowing Issue: Perspectives of School Administrators in Turkey

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ECNU Review of Education 2023年第1期6卷 84-104页

作者： Busra Kulakoglu yasar Kondakci Department of Educational Sciences Middle East Technical UniversityAnkaraTurkey

Purpose:As a borrowed concept,science,technology,engineering,and mathematics(STEM)education holds limited relevance in many country contexts.This study investigates how school administrators in Turkey view STEM education from three dimensions:(a)their understanding of STEM education,(b)their experiences of STEM implementations,and(c)their perception of their roles in STEM implementation.Design/Approach/Methods:This phenomenological study analyzes the perceptions of school principals working in prominent high schools in Turkey.Findings:The findings indicate that there are gaps in STEM implementation at both the conceptual level and the school level,including epistemological issues,infrastructural gaps,mismatch with overall organizational culture,and knowledge and skill gaps.Despite efforts to integrate STEM education into educational practices,significant deficiencies are making it an unrealistic practice in Turkey.Originality/Value:While the literature on STEM education is expanding,a few empirical studies focus on school management in relation to STEM education.Arguably,despite promising to transform science and mathematics teaching,STEM education appears to have limited relevance to science and mathematics teaching in Turkeyrendering it yet another example of concept and policy borrowing in education.

关键词： Educational policy perceptions of school principals policy borrowing STEM education

Energy-Efficient UAVs Coverage Path Planning Approach

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Computer Modeling in Engineering & Sciences 2023年第9期136卷 3239-3263页

作者： Gamil Ahmed Tarek Sheltami Ashraf Mahmoud Ansar yasar Computer Engineering Department Interdisciplinary Research Center of Smart Mobility and LogisticsKing Fahd University of Petroleum and MineralsDhahran31261Saudi Arabia Transportation Research Institute(IMOB) Hasselt UniversityHasselt3500Belgium

Unmanned aerial vehicles(UAVs),commonly known as drones,have drawn significant consideration thanks to their agility,mobility,and flexibility features.They play a crucial role in modern reconnaissance,inspection,intelligence,and surveillance missions.Coverage path planning(CPP)which is one of the crucial aspects that determines an intelligent system’s quality seeks an optimal trajectory to fully cover the region of interest(ROI).However,the flight time of the UAV is limited due to a battery limitation and may not cover the whole region,especially in large region.Therefore,energy consumption is one of the most challenging issues that need to be optimized.In this paper,we propose an energy-efficient coverage path planning algorithm to solve the CPP problem.The objective is to generate a collision-free coverage path that minimizes the overall energy consumption and guarantees covering the whole region.To do so,the flight path is optimized and the number of turns is reduced to minimize the energy consumption.The proposed approach first decomposes the ROI into a set of cells depending on a UAV camera footprint.Then,the coverage path planning problem is formulated,where the exact solution is determined using the CPLEX solver.For small-scale problems,the CPLEX shows a better solution in a reasonable time.However,the CPLEX solver fails to generate the solution within a reasonable time for large-scale problems.Thus,to solve the model for large-scale problems,simulated annealing forCPP is developed.The results show that heuristic approaches yield a better solution for large-scale problems within amuch shorter execution time than the CPLEX solver.Finally,we compare the simulated annealing against the greedy algorithm.The results show that simulated annealing outperforms the greedy algorithm in generating better solution quality.

关键词： Coverage path planning MILP CPLEX solver energy model optimization region of interest area of interest

Chemical Interpretation on the Multi-Stage Oxidation of Diethyl Ether

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Journal of Thermal Science 2023年第2期32卷 513-520页

作者： SAKAI Yasuyuki NAKAMURA Hisashi SUGITA Toru TEZUKA Takuya UYGUN yasar Department of Mechanical Systems Engineering Ibaraki UniversityIbaraki 316-8511Japan Institute of Fluid Science Tohoku UniversityMiyagi 980-8577Japan Graduate School of Engineering Tohoku UniversityMiyagi 980-8579Japan Mathematics and Logistics Jacobs University BremenBremen 28759Germany

Multi-stage ignition and/or double NTC(negative temperature coefficient)behavior resulted from the low-temperature oxidation of ether compounds are still not clearly explained.We have investigated the oxidation mechanism of a stoichiometric DEE(diethyl ether)/air mixture by using a micro flow reactor with a controlled temperature profile to see the detail of low-temperature weak flame structure.The simulation was also performed to understand the chemical kinetics mechanism of observed weak flame structure.Chemiluminescence measurement showed separated weak flame in the temperature range of 600 K-800 K.The simulation also qualitatively reproduced this separated weak flame,and showed four peak of heat release.From the reaction flow analysis,it was found that(1)O-O bond scission reaction of keto-hydroperoxide produced by DEE,(2)O-O bond scission reaction of CH3O2H,CH3CO3H,and C2H5O2H,(3)O-O bond scission reaction of H2O2,and(4)H+O2=O+OH are key chain branching reactions to explain the multi-stage oxidation.

关键词： diethyl ether micro flow reactor weak flame multi-stage oxidation reaction path

Stroke and dilated cardiomyopathy associated with celiac disease

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World Journal of Gastroenterology 2010年第18期16卷 2302-2304页

作者： Murat Dogan Erdal Peker Eren Cagan sinan Akbayram Mehmet Acikgoz Huseyin Caksen Abdurrahman Uner yasar Cesur Department of Pediatric Endocrinology Yuzuncu Yil UniversityMedical School Department of Pediatric Neurology Yuzuncu Yil UniversityMedical School Department of Pediatric Hematology Yuzuncu Yil UniversityMedical School Department of Pediatric Cardiology Yuzuncu Yil UniversityMedical School

Celiac disease(CD) is manifested by a variety of clinical signs and symptoms that may begin either in childhood or adult life.Neurological symptoms without signs of malabsorption have been observed for a long time in CD.In this report,an 8-year-old girl with CD presented with rarely seen dilated cardiomyopathy and stroke.The girl was admitted with left side weakness.Her medical history indicated abdominal distention,chronic diarrhea,failure to thrive,and geophagia.On physical examination,short stature,pale skin and a grade 2 of 6 systolic murmur were detected.Muscle strength was 0/5 on the left side,and 5/5 on the right side.Coagulation examinations were normal.Tests for collagen tissue diseases were negative.Factor V Leiden and prothrombin GA20210 mutations were negative.Tandem mass spectrophotometry and blood carnitine profiles were normal.Brain magnetic resonance imaging and cerebral angiography showed an infarction area at the basal ganglia level.Examinations of serologic markers and intestinal biopsy revealed CD.We emphasize that in differential diagnosis of ischemic stroke,CD should be kept in mind.

关键词： Celiac disease Stroke Cardiomyopathy Children