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A Mutual Authentication and Cross Verification Protocol for Securing Internet-of-Drones (IoD)

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Computers, Materials & Continua 2022年第9期72卷 5845-5869页

作者： Saeed ullah jan Irshad Ahmed Abbasi Fahad Algarni Department of Computer Science&IT University of MalakandChakadara18800Pakistan Faculty of Science&Arts Belqarn Department of Computer ScienceUniversity of BishaSabtul Alaya 61985Saudi Arabia Faculty of Computing and Information Technology University of BishaBisha 67714Saudi Arabia

With the rapid miniaturization in sensor technology,Internet-ofDrones(IoD)has delighted researchers towards information transmission security among drones with the control station server(CSS).In IoD,the drone is different in shapes,sizes,characteristics,and configurations.It can be classified on the purpose of its deployment,either in the civilian or military domain.Drone’s manufacturing,equipment installation,power supply,multi-rotor system,and embedded sensors are not issues for researchers.The main thing is to utilize a drone for a complex and sensitive task using an infrastructureless/self-organization/resource-less network type called Flying Ad Hoc Network(FANET).Monitoring data transmission traffic,emergency and rescue operations,border surveillance,search and physical phenomenon sensing,and so on can be achieved by developing a robust mutual authentication and cross-verification scheme for IoD deployment civilian drones.Although several protocols are available in the literature,they are either design issues or suffering from other vulnerabilities;still,no one claims with conviction about foolproof security mechanisms.Therefore,in this paper,the researchers highlighted the major deficits in prior protocols of the domain,i.e.,these protocols are either vulnerable to forgery,side channel,stolen-verifier attacks,or raised the outdated data transmission flaw.In order to overcome these loopholes and provide a solution to the existing vulnerabilities,this paper proposed an improved and robust public key infrastructure(PKI)based authentication scheme for the IoD environment.The proposed protocol’s security analysis section has been conducted formally using BAN(Burrows-Abadi-Needham)logic,ProVerif2.03 simulation,and informally using discussion/pragmatic illustration.While the performance analysis section of the paper has been assessed by considering storage,computation,and communication cost.Upon comparing the proposed protocol with prior works,it has been demonstrated that it is efficient and effective and recomme

关键词： Cryptography authentication confidentiality reachability ZSP

以熔盐为传热流体的塔式接收器技术对能量产生的影响

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以熔盐为传热流体的塔式接收器技术对能量产生的影响

作者： saad ullah Farooqi 哈尔滨工业大学

学位级别：硕士

在本文中,讨论了两种集中式太阳能发电站,其中一种具有主动存储系统,而另一种具有潜热存储系统。在主动存储系统系统中,中心塔接收器将熔盐加热至550℃,并储存在热箱中。当需要电力时,熔盐被送到蒸汽发生器,冷却后回到冷箱。本文提出的... 详细信息

在本文中,讨论了两种集中式太阳能发电站,其中一种具有主动存储系统,而另一种具有潜热存储系统。在主动存储系统系统中,中心塔接收器将熔盐加热至550℃,并储存在热箱中。当需要电力时,熔盐被送到蒸汽发生器,冷却后回到冷箱。本文提出的这个项目,具有20MW的发电能力,最长可达9小时的自主权。新开发熔盐用于传热和储存,该熔盐由Ca(NO),KNO,NaNO组成。该盐具有低成本的优点,并具有良好的性能。其熔点为140℃,热稳定性高达550℃。新开发用于设计潜热储存的相变材料NaCl+NaCO,其高熔点为630℃,相变焓为311J/g该系统可以实现更高的效率。在储存和蒸汽发生器之间以及罐和接收器之间需要传热液体传输能量。本文对发电站的主要部件进行详细的数学建模,包括定日镜,中央塔接收器,热盐储罐,冷箱,涡轮机和发电机,最后进行仿真,以模拟现实条件下发电站的性能。基于太阳和定日镜的位置,基于每年的每小时计算塔式接收器上收到的第一种能量。然后根据MATLAB中的热力学模型,对每个子系统进行仿真。仿真结果表明发电站表现良好,夏季需求高峰期,建议在中午12点至晚上8点之间进行运作。200万公斤的盐使发电站有能力在冬天每天工作4.5小时以上,在夏季每天工作9小时以上。在相同的条件下,使用高效率的多级涡轮机,高温储存,潜热储存设计将使我们达到24MW的功率。

关键词：集中式太阳能发电站传热液体相变材料中央塔接收器

降雨入渗触发非饱和煤矸石堆积边坡失稳的机理研究

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降雨入渗触发非饱和煤矸石堆积边坡失稳的机理研究

作者： Kaleem ullah jan Khan 吉林大学

学位级别：硕士

土坡的稳定性与降雨渗透过程有关,其特点是剪切强度降低以及吸力损失,从而最终导致了失稳。土坡失稳主要发生在降雨期间或降雨后,虽然已经被证明为降雨渗透导致土体强度降低以及孔隙水压力迅速增加而造成,但引发斜坡失稳的重要影响机理... 详细信息

土坡的稳定性与降雨渗透过程有关,其特点是剪切强度降低以及吸力损失,从而最终导致了失稳。土坡失稳主要发生在降雨期间或降雨后,虽然已经被证明为降雨渗透导致土体强度降低以及孔隙水压力迅速增加而造成,但引发斜坡失稳的重要影响机理还没有得到充分的讨论。降雨强度和降雨持续时间对边坡稳定性的影响,但降雨渗透过程对煤矸石堆积边坡稳定性的影响尚需深入研究。为此研究降雨入渗过程对土坡稳定性的影响,尤其对世界范围内广泛分布的矿渣堆积体稳定性及环境安全具有重要意义。降雨特征(降雨强度和持续时间)和土体的导水性影响着边坡的稳定状态及失效类型。一般来说,土坡破坏的机理有两种,即降雨湿润锋的传播导致垫层吸力的丧失以及地下水位的上升。到目前为止,仍然没有明确的指标来确定导致矿渣型边坡失效的主导参数。因此,本研究在开展东北阜新地区一煤矸石堆积边坡失稳机制研究中考虑了降雨渗透过程。通过收集已有资料、现场调查、实验室试验和数值模拟方法,较深入研究了煤矸石堆积边坡降雨诱发的失稳过程及其机理。采用渗流-应力耦合和非耦合有限元分析方法,对煤矸石堆积边坡的失效机理进行评价。采用物理模型测试分析了不同降雨条件下土坡中孔隙水压力的分布特征,采用有限元法数值方法按照渗流-应力耦合和非耦合两张方式研究了不同降雨持续时间(1天、2天、3天、4天和5天)和降雨强度对边坡变形破坏的影响。通过在坡面不同位置(坡顶、坡中、坡尖)设置监测点,观察并比较每次降雨后孔隙水压力的变化、变形规律和稳定性。煤矸石的高渗透性与在坡趾附近观察到的因水流而产生的最大变形进一步解释了坡体向下运动的原因,与现场观测和物理模型的观测结果有较好的一致性。研究结果还表明,渗透率的增加导致孔隙水压力的滞后性增加,土坡稳定系数下降。耦合分析中的安全系数(应力和孔隙水压力的耦合效应)与未耦合分析(水力反应效应)相比显著降低。为防止边坡进一步破坏,防止其对道路交通的影响,采用锚固与水平排水相结合的设计。建议在边坡顶部采用混凝土梁锚杆加固路基,在坡脚附近设置桩排。引入水平排水系统,分流雨水,保护边坡和道路的顶部和底部。采用极限平衡Bishop法分析了桩锚加固的效果,评价了加固方案对边坡安全系数的影响。结果表明:桩锚加固土边坡的安全系数由0.9提高到1.14;利用工程价值研究,在滑坡区设计水平排水系统,控制滑坡体内过量降雨入渗,保护坡顶和坡底道路,分流雨水。

关键词：煤矸石堆积体降雨入渗过程水-力耦合分析非饱和土力学安全系数治理措施

Mechanical and magneto-electronic properties of europium lanthanide-based cubic perovskites EuYO_(3)(Y=Cr, Mn, Fe): An ab initio study

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Journal of Rare Earths 2024年第3期42卷 562-569,I0005页

作者： Hayat ullah Azra Sarwar Sajad Ali Rabah Khenata Abdelmadjid Bouhemadou saad Bin-Omran Department of Physics Women University of Azad Jammu&Kashmir Bagh 10250Pakistan Department of Physics Abdul Wali Khan UniversityMardan23200KPPakistan LPQ3M Laboratory Institute of Science and TechnologyUniversity of Mascara29000MascaraAlgeria Laboratory for Developing New Materials and Their Characterization Farhat Abbas University Setif l19000SetifAlgeria Department of Physics and Astronomy College of ScienceKing Saud UniversityP.O.Box 2455Riyadh11451Saudi Arabia

Computational calculations using density functional theory(DFT) were performed for the first time using the full potential linearized augmented plane wave plus local orbital method(FP-LAPW + LO) to determine the structural, elastic, electronic and magnetic properties of europium-based cubic perovskites EuYO_(3)(Y=Cr, Mn, Fe). The exchange correlation potentials of GGA along with some analytical methods were adopted for the computation of structural and elastic properties. Moreover, the GGA + U formalism was also added for obtaining more precise electronic and magnetic properties, particularly to address the Eu-4f and Y-3d orientations in the spin-polarized double cell symmetry. The observed lattice parameters of these compounds are consistent with experiment. The observed bulk moduli predict that EuCrO_(3) is harder and less compressible than EuMnO_(3) and EuFeO_(3). The calculated tolerance factors of these compounds are within the cubic symmetry range. Our computed critical radius of EuCrO_(3) shows that EuCrO_(3) has a larger migration energy. Based on their elastic properties, these compounds are ductile in nature. We also computed the thermal properties of these compounds. The band structures and density of states show that these compounds are metallic in character. The lowest ground state energy and magnetic moments of these compounds expose their ferromagnetic nature. The metallic nature and strong ferromagnetism of these compounds make them promising applicants for application in spintronic.

关键词： Perovskites GGA+U Elastic constants Band structure Magnetic moments Rare earths

A PHEMT Based Wideband LNA for Wireless Applications

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China Communications 2015年第10期12卷 108-116页

作者： Muhammad saad Khan ZHANG Hongxin HE Pengfei Sulman Shahzad Rahat ullah School of Electronic Engineering Beijing University of Posts and Telecommunications(BUPT) Electrical Engineering Department University College of Engineering & TechnologyBahauddin Zakariya University Institute of Science and Technology for Opto-electronic Information Yantai University State Key Laboratory of Information Photonics and Optical Communications Beijing University of Posts and Telecommunications

This work is about the development of a super low noise amplifier with minimum power consumption and high gain for several wireless applications.The amplifier operates at frequency bands of 0.9-2.4 GHz and can be used in many applications like Wireless local area network(WLAN),WiFi,Bluetooth,ZigBee and Global System for mobile communications(GSM).This new design can be employed for the IEEE 802.15.4 standard in industrial,scientific and medical(ISM) Band.The enhancement mode pseudomorphic high electron mobility transistor PHEMT is used here due to its high linearity,better performance and less noisy operation.The common source inductive degeneration method is employed here to enhance the gain of amplifier.The amplifier produces a gain of more than 17 dB and noise figure of about 0.5 dB.The lower values of S11 and S22 reflect the accuracy of impedance matching network placed at the input and output sides of amplifier.Agilent Advance Design System(ADS) is used for the design and simulation purpose.Further the layout of design is developed on the FR4 substrate.

关键词：宽带低噪声放大器 PHEMT 无线应用赝配高电子迁移率晶体管全球移动通信系统设计系统 ZigBee 阻抗匹配网络

新型Al/CuFe多层核壳颗粒增强铝基复合材料的显微组织和力学性能

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Transactions of Nonferrous Metals Society of China 2022年第6期32卷 1822-1833页

作者： Rashid ALI Fahad ALI Aqib ZAHOOR Rub Nawaz SHAHID Naeem ul Haq TARIQ Zafar IQBAL Adnan Qayyum BUTT saad ullah Hasan Bin AWAIS Department of Metallurgy and Materials Engineering Pakistan Institute of Engineering and Applied Sciences(PIEAS)IslamabadPakistan Materials Division Pakistan Institute of Nuclear Science and Technology(PINSTECH)IslamabadPakistan

采用不同烧结工艺制备新型Al/Cu Fe多层核壳颗粒增强铝基复合材料(AMCs),研究其对显微组织和力学性能的影响。分别采用电置换法和化学镀法在铝粉颗粒上沉积Cu层和Fe层,制备多层Al/Cu Fe核壳颗粒。采用X射线衍射(XRD)、扫描电子显微镜(SE... 详细信息

采用不同烧结工艺制备新型Al/Cu Fe多层核壳颗粒增强铝基复合材料(AMCs),研究其对显微组织和力学性能的影响。分别采用电置换法和化学镀法在铝粉颗粒上沉积Cu层和Fe层,制备多层Al/Cu Fe核壳颗粒。采用X射线衍射(XRD)、扫描电子显微镜(SEM)/能谱(EDX)、密度计、显微硬度和压缩试验等方法对复合材料进行表征。结果表明,在放电等离子烧结复合材料中,由于沉积层向金属间化合物相转变,界面反应程度提高,复合材料的相对密度(99.26%)、显微硬度(165 HV0.3)和强度(572 MPa)均显著提高。此外,热压复合材料壳层结构中存在的未转化Cu导致其断裂应变最高(20.4%)。研究结果对通过选择合适的烧结路径来调整AMCs的显微组织和控制其力学性能具有重要意义。

关键词：核壳增强相铝基复合材料化学镀烧结工艺放电等离子烧结界面反应

RBF-FD Method for Some Dispersive Wave Equations and Their Eventual Periodicity

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Computer Modeling in Engineering & Sciences 2020年第5期123卷 797-819页

作者： Marjan Uddin Hameed ullah jan Muhammad Usman Department of Basics Sciences UETPeshawarPakistan Department of Mathematics University of DaytonDaytonUSA

In this paper,we approximate the solution and also discuss the periodic behavior termed as eventual periodicity of solutions of(IBVPs)for some dispersive wave equations on a bounded domain corresponding to periodic forcing.The constructed numerical scheme is based on radial kernels and local in nature like finite difference method.The temporal variable is executed through RK4 scheme.Due to the local nature and sparse differentiation matrices our numerical scheme efficiently recovers the solution.The results achieved are validated and examined with other methods accessible in the literature.

关键词： RBFs meshless methods RBF-FD scheme eventual periodicity BBM and KdV type equations.

Colorless WDM-PON Using Single Side Band Carrier Suppressed Signals Mitigating Carrier Rayleigh Backscattering

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China Communications 2016年第12期13卷 150-161页

作者： Rahat ullah Bo Liu Qi Zhang Yousaf Khan Amjad Ali Qinghua Tian Feng Tian M.saad Khan Tabinda Salam Sibghat ullah Lijia Zhang Xiangjun Xin State Key Laboratory of Information Photonics and Optical Communications Beijing University of Posts and TelecommunicationsNo.10 Xitucheng Road Beijing China 100876 School of Electronic Engineering Beijing University of Posts and Telecommunications No. 10 Xitucheng Road Beijing China 100876 Electrical Engineering Department Iqra University Peshawar Pakistan. Sarhad University Peshawar Pakistan 25000 School of Information and Communication Beijing University of Posts and TelecommunicationsNo. 10 Xitucheng Road Beijing China 100876

A new scheme is offered for minimizing carrier Rayleigh backscattering(CRB) in single feeder fiber based wavelength division multiplexed passive optical network(WDM-PON). The proposed scheme is based on single side band carrier suppressed(SSBCS) signal, both at network and receiver sides, used for the first time at optical line terminal(OLT) and optical network unit(ONU) sides. We use dual-drive Mach-zehnder modulator(DD-MZM) for generating SSB-CS signals, which decreases the expense per bit in full transmission. SSB-CS mitigates CRB, both at OLT and ONU sides, because of having no chance of reflections from the carrier. Since no extra dedicated RF or laser source is used at ONU side, we thus achieve cost effective colorless WDM-PON system. Suppressed signals from four channels, each of 10 Gbps, are multiplexed before injecting into the fiber span of 25 km at OLT. At ONU side, half of the downlink power is used for re-modulating the data signal. The simulation results show an errorfree transmission. Moreover, the detailed power budget calculations show that the proposed scheme can be sought out for splitting ratio up to 128. Hence it offers enough system's margin for unseen losses.

关键词： Carrier Rayleigh backscattering dual drive Mach-zehnder modulator single side band suppress carrier on-off keying

X-Band Power Amplifier for Next Generation Networks Based on MESFET

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China Communications 2017年第4期14卷 11-19页

作者： Muhammad saad Khan Hongxin Zhang Fan Zhang Sulman Shahzad Rahat ullah Sajid Ali Qasim Ali Arain Manzoor Ahmed School of Electronic Engineering Beijing University of Posts and Telecommunications (BUPT) Beijing 100876 China Beijing Key Laboratory of Work Safety Intelligent Monitoring Beijing University of Posts and Telecommunications Beijing 100876 china College of Information Science and Electrical Engineering Zhejiang University Hangzhou Zhejiang 310027china Electrical Engineering Department University College of Engineering & Technology Bahauddin Zakariya University Multan Pakistan State Key Laboratory of Information Photonics and Optical Communications Beijing University of Posts and Telecommunications Beijing 100876 China Department of Coxnputer Science D.G. Khan Campus. University of Education Lahore Pakistan Future lnternet & Communication Lab (FIB) Department of Electronic Engineering Tsinghua University Beijing 100084 China

Advanced wireless standards of communication like 3GPP and LTE are becoming more and more efficient and with this evolution of communication systems mobile equipment is also become smaller and smaller. Power amplifier designing has become a very crucial task in this era where efficiency and size are the main concern of any designer. In this paper we have design and analyzed X-band Class E Metal-semiconductor field effect transistor(MESFET) based Power Amplifier. This device targets the devices which use OFDM technique to improve their spectral efficiency for the next generation communication systems. Microstrip lines are used to achieve small size for our design instead of lumped components. Load Pull measurements are used to get MESFET input and output impedances optimum values. For linear and non linear operation small signal mathematical model of the design is used. To reduce thermal losses FR4 substrate is used to increase PA efficiency. Our designs shows small values of input and output return loss of about-22.3d B and-23.716 d B achieving a high gain of about25.6 d B respectively, with PAE of about 30 % having stability factor greater than 1 and 21.894 d Bm of output power.

关键词： MESFET X-band power amplifier advance design system PAE LTE