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When LoRa meets distributed machine learning to optimize the network connectivity for green and intelligent transportation system

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Green Energy and Intelligent Transportation 2024年第3期3卷 24-41页

作者： Malak Abid Ali Khan Hongbin Ma Arshad Farhad asad mujeeb Imran Khan Mirani Muhammad Hamza National Key Lab of Autonomous Intelligent Unmanned Systems School of AutomationBeijing Institute of TechnologyBeijing 100081China Department of Computer Science Namal UniversityPakistan Department of Electrical Engineering Tsinghua UniversityBeijing 100084China Faculty of Information Technology Beijing University of TechnologyBeijing 100124China School of Mechanical Engineering Beijing Institute of TechnologyBeijing 100081China

LoRa technology contributes to green energy by enabling efficient,long-range communication for the Internet of Things(IoT).This paper addresses the challenges related to coverage range in outdoor monitoring systems utilizing LoRa,where the network performance is affected by the density of gateways(GWs)and end devices(EDs),as well as environmental *** mitigate interference,data throughput losses,and high-power consumption,the proposed spreading factor(SF)and hybrid(data rate|SF)models dynamically adjust the transmission *** orchestration of concurrent data modifications within the network server(NS)is crucial for uninterrupted communication between GWs and EDs,especially in monitoring electric vehicle(EV)stations to reduce traffic congestion and *** K-means and density-based spatial clustering of applications with noise(DBSCAN)algorithms optimizes ED allocation,averts data congestion,and improves the signal-tointerference noise ratio(SINR).These methods ensure seamless information reception by meticulously allocated EDs across various GW *** estimate the free-space losses(FSL),a log-distance path loss model(log-PL)is *** various bandwidths(BWs),bidirectional communications,and duty cycles(DCs)helps to prevent saturation,thus prolonging the operational lifespan of *** findings reveal a notable packet rejection rate(PRR)of 0%for the DBSCAN(hybrid model).In contrast,the K-means exhibits a PRR ranging from 5%(hybrid model)to 35.29%(SF model)for the ten GWs ***,the network saturation is reduced to 10.185%and 9.503%,respectively,highlighting an improvement in the average efficiency of slotted ALOHA(91.1%)and pure ALOHA(90.7%).These enhancements increase the lifespan of EDs to 15,465.27 days.

关键词： DBSCAN Green transportation Hybrid model Intelligent transportation K-means

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英国配电网长期增量成本定价模型分析及对中国增量配电网启示

英国配电网长期增量成本定价模型分析及对中国增量配电网启示

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作者： asad mujeeb（阿萨德）华北电力大学(北京)

学位级别：硕士

配电网系统是现代电力系统的重要组成部分。近年来,随着能源需求不断增加,可再生能源在电力系统中的渗透率不断提高。越来越多的分布式发电机组(DGs,Distributed Generators)接入配电网,以满足电力系统用户的用电需要。目前,大量分布式... 详细信息

配电网系统是现代电力系统的重要组成部分。近年来,随着能源需求不断增加,可再生能源在电力系统中的渗透率不断提高。越来越多的分布式发电机组(DGs,Distributed Generators)接入配电网,以满足电力系统用户的用电需要。目前,大量分布式发电机组的接入促使配电网系统逐渐向现代化、智能化演进,也推动了分散式电力市场的发展。英国政府向国内14家配电网络运营商(DNO)施压,要求其在配电网系统中接入更多的分布式发电机组,并明确提出指标,要求到2020年时可再生能源机组发电量占全国发电量的15%,到2050年提高到80%。分布式发电机组在配电网中大量应用可以使电网更加绿色、提高电网供电可靠性,但从长远来看,可再生能源的波动性和间歇性也为配电网安全运行带来了诸多挑战。配电网定价对于电网建设非常重要,它保证了电网增量投资后的收益和成本回收。其中,电网运行安全是影响配电网定价计算和分配的重点考虑因素。若电力系统中造成了 N-1的突发情况,消费者和供应商无法获知网络运行情况,配电网定价问题就变得非常棘手。为了解决这一问题,本文研究在英国配电网长期增量成本(LRIC,long run incremental cost)定价模型的基础上对网络安全进行了分析。本研究提出一种新的深度强化学习方法,称为深度强化学习算法(DQN,deep reinforcement learning algorithm),以优化网络中的无功功率值,在保持网络安全的前提下,平衡并降低网络定价价格。该方法以IEEE 14节点系统为数学模型,用DQN算法伪码在MATLAB中进行了实际仿真。分析了节点注入网络前后有无安全因素的网络安全。通过多次迭代优化网络无功功率,最终得到了理想的结果。本文还介绍了中国增量配电改革情况和中国配电定价改革情况,分析了英国配电网定价方法对中国的经验启示。

关键词：配电网定价长期增量成本(LRIC) 网络安全无功功率深度强化学习节点注入

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ULAM-HYERS-RASSIAS STABILITY AND EXISTENCE OF SOLUTIONS TO NONLINEAR FRACTIONAL DIFFERENCE EQUATIONS WITH MULTIPOINT SUMMATION BOUNDARY CONDITION

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Acta Mathematica Scientia 2020年第2期40卷 589-602页

作者： Syed Sabyel HAIDER mujeeb Ur REHMAN School of Natural Sciences National University of Sciences and TechnologyH-12 Islamabad44000Pakistan

The purpose of this study is to acquire some conditions that reveal existence and stability for solutions to a class of difference equations with non-integer orderμ∈(1,2].The required conditions are obtained by applying the technique of contraction principle for uniqueness and Schauder’s fixed point theorem for ***,we establish some conditions under which the solution of the considered class of difference equations is generalized Ulam-Hyers-Rassias *** for the illustration of results is given.

关键词： Fractional difference equation Green's function existence and uniqueness Ulam-Hyers-Rassias stability summation boundary condition

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THREE POINT BOUNDARY VALUE PROBLEMS FOR NONLINEAR FRACTIONAL DIFFERENTIAL EQUATIONS

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Acta Mathematica Scientia 2011年第4期31卷 1337-1346页

作者： mujeeb ur Rehman Rahmat Ali Khan Naseer Ahmad Asif National University of Sciences and Technology (NUST) Centre for Advanced Mathematics and Physics University of Malakand Chakdara Dir(L) Khyber Pakhtunkhawa Pakistan

In this paper, we study existence and uniqueness of solutions to nonlinear three point boundary value problems for fractional differential equation of the type c D δ 0＋ u（t） = f （t, u（t）, c D σ 0＋ u（t））, t ∈ [0, T ], u（0） = αu（η）, u（T ） = βu（η）, where 1 〈 δ 〈 2, 0 〈 σ 〈 1, α, β∈ R, η∈ （0, T ）, αη（1 -β）＋（1-α）（T βη） = 0 and c D δ 0＋ , c D σ 0＋ are the Caputo fractional derivatives. We use Schauder fixed point theorem and contraction mapping principle to obtain existence and uniqueness results. Examples are also included to show the applicability of our results.

关键词： fractional differential equations three point boundary conditions existence and uniqueness results

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Electronic and optical properties of TiO_2 and its polymorphs by Z-scan method

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Chinese Physics B 2014年第8期23卷 340-344页

作者： S. Divya V P N Nampoori P Radhakrishnan A mujeeb International School of Photonics Cochin University of Science and Technology

TiO2 is a material which has attracted considerable attention from the scientific community for its innumerable prop- erties. TiO2 is known to exist in nature in three different crystalline structures： rutile, anatase, and brookite. Anatase and rutile TiO2 films have been widely characterized for their potential applications in solar cells, self-cleaning coatings, and photocatalysis. In the present report, the third-order nonlinear susceptibilities of TiO2 and its polymorphs, anatase, and rutile, prepared by the sol-gel technique followed by heat treatment are investigated using the Z-scan technique at a wavelength of 532 nm with a duration of 7 ns. Imaginary and real values of Z（3） for amorphous, anatase, and rutile are also calculated and found to be 5 × 10^-19 m2/V2, 27 × 10^-19 m2/V2, 19 × 10^-19 m2/V2, respectively. It is found that the values of the optical constants of amorphous TiO2 after heat treatment vary considerably. It is assumed that this could be due to the variation in the electronic structure of TiO2 synchronous with the formation of its polymorphs, anatase, and rutile. Amorphous TiO2 is marked by the localization of the tail states near the band gap, whereas its crystalline counterparts are characterized by completely delocalized tail states.

关键词： excitons reverse saturable absorption (RSA) excitonic nonlinearity

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Non-Invasive Early Diagnosis of Obstructive Lung Diseases Leveraging Machine Learning Algorithms

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Computers, Materials & Continua 2022年第9期72卷 5681-5697页

作者： mujeeb Ur Rehman Maha Driss Abdukodir Khakimov Sohail Khalid Department of Electrical Engineering Riphah International UniversityIslamabad44000Pakistan Security Engineering Lab Prince Sultan UniversityRiyadh12435Saudi Arabia RIADI Laboratory National School of Computer ScienceUniversity of ManoubaManouba2010Tunisia Peoples’Friendship University of Russia(RUDN University) Moscow117198Russia

Lungs are a vital human body organ,and different Obstructive Lung Diseases(OLD)such as asthma,bronchitis,or lung cancer are caused by shortcomings within the ***,early diagnosis of OLD is crucial for such patients suffering from OLD since,after early diagnosis,breathing exercises and medical precautions can effectively improve their health state.A secure non-invasive early diagnosis of OLD is a primordial need,and in this context,digital image processing supported by Artificial Intelligence(AI)techniques is reliable and widely used in the medical field,especially for improving early disease ***,this article presents an AIbased non-invasive and secured diagnosis for OLD using physiological and iris *** research work implements different machine-learning-based techniques which classify various subjects,which are healthy and effective *** iris features include gray-level run-length matrix-based features,gray-level co-occurrence matrix,and statistical *** features are extracted from iris ***,ten different classifiers and voting techniques,including hard and soft voting,are implemented and tested,and their performances are evaluated using several parameters,which are precision,accuracy,specificity,F-score,and *** on the statistical analysis,it is concluded that the proposed approach offers promising techniques for the non-invasive early diagnosis of OLD with an accuracy of 97.6%.

关键词： Obstructive lung disease non-invasive diagnosis machine learning physiological features voting techniques

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Machine learning for intrusion detection in industrial control systems:challenges and lessons from experimental evaluation

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Cybersecurity 2021年第1期4卷 415-426页

作者： Gauthama Raman M.R. Chuadhry mujeeb Ahmed Aditya Mathur iTrust Singapore University of Technology and Design(SUTD)8 Somapah RdSingapore 487372Singapore University of Strathclyde 16 Richmond StGlasgow G11XQUnited Kingdom

Gradual increase in the number of successful attacks against Industrial Control Systems(ICS)has led to an urgent need to create defense mechanisms for accurate and timely detection of the resulting process *** this end,a class of anomaly detectors,created using data-centric approaches,are gaining *** machine learning algorithms such approaches can automatically learn the process dynamics and control strategies deployed in an *** use of these approaches leads to relatively easier and faster creation of anomaly detectors compared to the use of design-centric approaches that are based on plant physics and *** the advantages,there exist significant challenges and implementation issues in the creation and deployment of detectors generated using machine learning for city-scale *** this work,we enumerate and discuss such *** presented is a series of lessons learned in our attempt to meet these challenges in an operational plant.

关键词： Industrial control systems ICS security Machine learning Intrusion detection Testbed and experimental Study

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Optimization of dual effects of Mg–1Ca alloys on the behavior of chondrocytes and osteoblasts in vitro

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Progress in Natural Science:Materials International 2014年第5期24卷 433-440页

作者： Yana Dou Ayeesha mujeeb Yufeng Zheng Zigang Ge Center for Biomedical Materials and Tissue Engineering Academy for Advanced Interdisciplinary Studies Peking University Department of Materials Science and Engineering College of Engineering Peking University Department of Biomedical Engineering College of Engineering Peking University Arthritis Clinic and Research Center Peking University People's Hospital

Mg ions can enhance the proliferation and redifferentiation of chondrocytes and the osteogenic differentiation of osteoblasts at specific concentrations, respectively. However, degradation of Mg alloys at varying degradation rates could lead to complex changes in the surrounding tissue environment, such as changes in the dynamic concentration of Mg ions and subsequent p H value. Considering the above mentioned factors, the comprehensive effects of Mg alloys on chondrocytes and osteoblasts behaviors have not yet been optimized. In this study, we evaluated the effects of Mg–1Ca microspheres on cell behavior with an aim to optimize conditions favorable for both cell types. Cells were cultured with Mg–1Ca microspheres prepared using the following concentrations: 250 μg/ml, 500 μg/ml and 1000 μg/ml. At specific time points,cytotoxicity, expression of specific genes and extracellular matrix deposition by cells(Alizarin Red Staining of osteoblasts and Alcian blue staining for chondrocytes) were evaluated. The experimental results revealed that Mg–1Ca microspheres prepared at a concentration of 250 μg/ml were optimum for both cell types, where chondrocytes were found to be in hypertrophy state while osteoblasts in close proximity to the microspheres showed osteogenetic differentiation. Interestingly, a slight change in osteoblasts behavior was observed nearer to and at a relative distance away from Mg–1Ca microspheres, an important observation for administering the application of microspheres as potential scaffolds.

关键词： Magnesium Degradation Chondrocyte Phenotype

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Traumatic abdominal wall hernia:a rare and often missed diagnosis in blunt trauma

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World Journal of Emergency Medicine 2022年第6期13卷 492-494页

作者： Sohil Pothiawala Sunder Balasubramaniam mujeeb Taib Savitha Bhagvan Trauma Service Auckland City HospitalAuckland 1023New Zealand

Dear editor,Traumatic abdominal wall hernia(TAWH)is defined as disruption of the abdominal wall musculature and fascia with herniation of intra-abdominal contents,in the absence of surgery to that area of the abdominal wall.[1]It is rare,with an incidence of 0.17%-0.90%in patients with blunt abdominal trauma.[2,3]Deceleration forces caused by falls from height or seat belt injuries are the most common causes of TAWH.[4]Low-energy blunt injuries from bicycle or motorcycles handlebars or charging animals are less frequent *** to the rare incidence and complex presentation of this condition with other distracting injuries,this diagnosis is often not considered,resulting in missed or delayed *** present a case of a 46-year-old male who suffered major abdominal trauma,and was found to have TAWH as well as intra-abdominal organ injury.

关键词： injuries abdominal diagnosis

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Intensity and composition-dependent sign reversal of non-linearity in TiO_2/CeO_2 nanocomposites

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Chinese Physics B 2014年第3期23卷 298-302页

作者： S.Divya V.P.N.Nampoori P.Radhakrishnan A.mujeeb International School of Photonics Cochin University of Science and Technology

CeO2/TiO2 composite nanoparticles with different Ce/Ti molar ratios have been successfully synthesized via sol-gel method. It was found that the band gap of the nanocomposite is tunable by varying Ce/Ti content. The nonlinear response of the sample was studied by using the nanosecond laser pulses from a Q switched Nd：Yag laser employing the Z-scan method. Open aperture Z-scan experiment revealed that with the increase in the CeO2 amount in the nanocomposite, the non-linearity of the composite increases, and it was assumed that this could be due to the modification of TiO2 dipole symmetry by the addition of CeO2. Closed aperture Z-scan experiment showed that when the CeO2 amount increases, positive nonlinear refraction decreases, and this could be attributed to the increase in the two photon absorption which subsequently suppresses the nonlinear refraction.

关键词： sol-gel method non-linearity Z-scan experiment reversesaturation absorption curve

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