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基于动态极坐标参数化的遥感影像匹配方法

地球信息科学学报 2019年第10期21卷 1586-1593页

作者：孙嘉玉左正康孙逸渊 sana ullah 张瑞华赵海盟空间信息集成与3S工程应用北京市重点实验室(北京大学) 北京100871 桂林航天工业学院广西高校无人机遥测重点实验室桂林541004

图像匹配作为三维重建至关重要的环节,其精度直接影响了平差优化、正射校正等模块的精度。对于城镇、农场等特征密集型区域,特征距离小,相似性强,易于匹配图像;而针对草地、沙漠等特征不明显区域,特征距离大,如果使用特征点匹配的方法,... 详细信息

图像匹配作为三维重建至关重要的环节,其精度直接影响了平差优化、正射校正等模块的精度。对于城镇、农场等特征密集型区域,特征距离小,相似性强,易于匹配图像;而针对草地、沙漠等特征不明显区域,特征距离大,如果使用特征点匹配的方法,严格阈值下难以获得足够数量的匹配对,放宽阈值又将引入较多误匹配对,这也是导致稀疏点云不够均匀的原因之一。在此场景下,本文提出了基于动态极坐标参数化的无人机正视影像匹配算法,首先对图像做极坐标参数变化,采用动态策略解决极轴方向采样不均匀的问题,使用最小二乘法对得到的极坐标影像对做位移方向上的匹配,匹配后得到的旋转量和平移量,将该结果和SIFT算法的结果做比较。本文设计了2组实验,即参数已知的解算实验和参数未知的解算实验,且每组实验进行3次。在同等配置的计算机上,对两张7360像素×5400像素,32位的影像,本文方法的位姿解算时间相比SIFT的时间减少约57%,二者求得的位姿差通常小于1%。结论表明二者的结果在精度上表现相当,在时间上明显优于SIFT算法,具有实际的应用价值。

关键词：无人机极坐标遥感影像匹配三维重建光束法平差参数化影像拼接

协同性的介电损耗和磁损耗使少层WS2纳米片与NiO纳米粒子的杂化物具有优异的微波吸收性能

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Science Bulletin 2020年第2期65卷 138-146,88页

作者：张德庆熊英飞程俊业柴吉星刘婷婷巴学巍 sana ullah 郑广平严明曹茂盛 School of Materials Science and Engineering Qiqihar UniversityQiqihar 161006China Department of Mechanical Engineering Hong Kong Polytechnic UniversityHong KongChina Department of Materials Science and Engineering and Shenzhen Key Laboratory for Additive Manufacturing of High-performance MaterialsSouthern University of Science and TechnologyShenzhen 518055China School of Materials Science and Engineering Beijing Institute of TechnologyBeijing 100081China

由于高的比表面、层状结构以及特殊的电子结构,二硫化钨在电磁波吸收领域受到了科研人员的广泛关注.然而,二硫化钨有限的电磁吸收能力和带宽还有待进一步的改进,以满足其作为电磁吸收材料的实际应用.本研究采用水热法制备了具有异质结构... 详细信息

由于高的比表面、层状结构以及特殊的电子结构,二硫化钨在电磁波吸收领域受到了科研人员的广泛关注.然而,二硫化钨有限的电磁吸收能力和带宽还有待进一步的改进,以满足其作为电磁吸收材料的实际应用.本研究采用水热法制备了具有异质结构的WS2/NiO杂化材料,并将其发展成为电磁波吸收基体.在4.27 mm厚度下,掺20%NiO杂化物材料的最大反射损失可达-53.31 dB;RL值小于-10 dB的带宽范围为4.54~18 GHz,此时吸波材料的厚度在3.5~5.5 mm.研究结果表明,WS2/NiO杂化材料优异的吸波性能是由于磁性Ni O的加入,形成了WS2和Ni O的异质界面,从而引起杂化材料协同的磁损耗和介电损耗,这为设计优异的吸波材料以及实际的应用开辟了新的途径.

关键词： 2D nanosheets WS2/NiO hybrids Hetero-structures Microwave absorption

Lady Windermere Syndrome: An Interesting Clinical and Radiological Presentation

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Exploring dielectric phenomena in sulflower-like nanostructures via Monte Carlo technique

Case Reports in Clinical Medicine 2022年第9期

作者： farid khan wajiha ali muhammad imtiaz uzma sana ullah

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Communications in Theoretical Physics 2024年第4期76卷 188-198页

作者： N Saber Z Fadil Hussein Sabbah A Mhirech B Kabouchi L Bahmad Chaitany Jayprakash Raorane Siva Sankar sana Hassan Fouad Mohamed Hashem Laboratory of Condensed Matter and Interdisciplinary Sciences(LaMCScI) Research Unit Labelled CNRSTURL-CNRST-17.Faculty of SciencesPO Box 1014Mohammed Ⅴ University in RabatMorocco College of Engineering and Technology American University of the Middle EastEgaila 54200Kuwait School of Chemical Engineering Yeungnam UniversityGyeongsan38541Republic of Korea Applied Medical Science Department Community CollegeKing Saud UniversityPO Box 11433Riyadh Saudi Arabia Department of Dental Health College of Applied Medical SciencesKing Saud UniversityPO Box 12372RiyadhSaudi Arabia

This research focuses on the electric behavior of a mixed ferrielectric sulflower-like *** structure includes a core with spin S_(i)^(Z)-1 atoms and a shell with spin σ_(j)^(Z)-5/2 *** Blume–Capel model and the Monte Carlo technique(MCt)with the Metropolis algorithm are *** are established for absolute zero,investigating stable spin configurations correlated with various physical *** MCt method explores phase transition behavior and electric hysteresis cycles under different physical parameters.

关键词： sulfower-like nanostructure dielectric characteristics Monte Carlo technique phase transition phase diagrams electric hysteresis

Homologous heterostructure of MoS2 and MoO2 coupled with carbon layers as cathode catalyst for rechargeable lithium-oxygen batteries

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Rare Metals 2024年第7期43卷 3383-3390页

作者： Yi-Ming Zhang Zhao-Rui Zhou Lan-Ling Zhao Ye-Bing Li Rui-Feng Li Ya Zhou sana Shoukat Abulgasim-Ahmed-Abbaker Adam Jun Wang Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials (Ministry of Education) Shandong University Shenzhen Research Institute of Shandong University School of Physics Shandong University

Lithium-oxygen batteries tend to experience high overpotentials because of the sluggish oxygen reduction reaction and oxygen evolution reaction during cycling.A potential solution to address this issue is to develop a... 详细信息

关键词： Electrolytic reduction

BIoMT:A Blockchain-Enabled Healthcare Architecture for Information Security in the Internet of Medical Things

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Computer Systems Science & Engineering 2023年第9期46卷 3667-3684页

作者： Sahar Badri sana ullah Jan Daniyal Alghazzawi Sahar Aldhaheri d Nikolaos Pitropakis Information Systems Department Faculty of Computing and Information TechnologyKing Abdulaziz UniversityJeddah80200Saudi Arabia School of Computing Edinburgh Napier UniversityEdinburghEH105DYUK

Rapid technological advancement has enabled modern healthcare systems to provide more sophisticated and real-time services on the Internet of Medical Things(IoMT).The existing cloud-based,centralized IoMT architectures are vulnerable to multiple security and privacy *** blockchain-enabled IoMT is an emerging paradigm that can ensure the security and trustworthiness of medical data sharing in the IoMT *** article presents a private and easily expandable blockchain-based framework for the *** proposed framework contains several participants,including private blockchain,hospitalmanagement systems,cloud service providers,doctors,and *** security is ensured by incorporating an attributebased encryption ***,an IoT-friendly consensus algorithm is deployed to ensure fast block validation and high scalability in the IoMT *** proposed framework can perform multiple healthcare-related services in a secure and trustworthy *** performance of blockchain read/write operations is evaluated in terms of transaction throughput and *** outcomes indicate that the proposed scheme achieved an average throughput of 857 TPS and 151 TPS for read and write *** average latency is 61 ms and 16 ms for read and write operations,respectively.

关键词： Blockchain cybersecurity IoT IoMT smart healthcare

Effect of Different Levels of Phosphorus and Method of Application on the Growth and Yield of Wheat

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Natural Science 2016年第7期8卷 305-314页

作者： Shahzado Noonari Shahmir Ali Kalhoro Amjad Ali Amanullah Mahar Sajjad Raza Muneer Ahmed Syed Fayaz Ali Shah sana ullah Baloch Department of Agronomy Sindh Agriculture University Tandojam Pakistan Institute of Soil & Water Conservation Northwest A&F University Yangling China Faculty of Agriculture Lasbela University of Agriculture Water and Marine Science Uthal Pakistan College of Natural Resources & Environment Northwest A&F University Yangling China Agricultural Research Institute (Tarnab) Peshawar Pakistan Key Laboratory of Crop Physiology Ecology and Production Huazhong Agricultural University Wuhan China

An experiment was conducted to evaluate the productivity of wheat under different levels of phosphorus and method of application at Department of Agronomy, Sindh Agriculture University, Tandojam. Experiment was laid out in a RCBD (factorial) with three replications. The treatments were four phosphorus levels (P1 = 0 Kg?ha–1 + Recommended Nitrogen, P2 = 30 Kg?ha–1 + Recommended Nitrogen, P3 = 60 Kg?ha–1 + Recommended Nitrogen and P4 = 90 Kg?ha–1 + Recommended Nitrogen) and two placement methods (A1 = Drilling method and A2 = Broadcast method). The statistical analysis of phosphorus levels and placement exhibited significant differences to the maturity days, plant height, tiller production, spike length, grains per spike, seed index, harvest index and grain yield ha–1. However, the interactions of P levels and placement in all crop characters were non-significant except the grain yield/ha–1. The results revealed that application of 90 kg P ha–1 prolonged 143 days for maturity, taller plants (100.16 cm), more tiller plant–1 (13.50), lengthy spikes (12.83 cm), more grains spike–1 (51.33), heavier seed index (48.16 g), better harvest index (50.82%) and satisfactory grain yield (4240.50 Kg?ha–1). The unit increase in grain yield was positively correlated with the increased values of observed crop parameters by extending the values of maturity r = 0.85, plant height r = 0.94, tillers plant r = 0.96, spike length r = 0.95, grains spik–1 r = 0.97, seed index r = 0.95 and harvest index r = 0.97. It was concluded that 90 kg P ha–1 was superior level of phosphorus if, applied with seed drilling for obtaining satisfactory grain yield of wheat crop.

关键词： Wheat Phosphorous Broadcasting Drilling Yield

Precocious Puberty in a 5-Year-Old Girl with a Giant Hypothalamic Hamartoma Discovered Perinatally: Case Report

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Open Journal of Endocrine and Metabolic Diseases 2024年第4期14卷 101-106页

作者： Ghita Bourkadi sanae Habibi sana Abourazzak Moustapha Hida Department of Endocrinology Diabetology Metabolic Diseases and Nutrition Hassan II University Hospital Fez Morocco Department of Pediatrics Hassan II University Hospital Fez Morocco Faculty of Medicine and Pharmacy Sidi Mohamed Ben Abdellah University Fez Morocoo

Background: Hypothalamic hamartoma is a rare non-neoplastic lesion, typically identified in early childhood during investigations for precocious puberty and/or gelastic seizures. However, cases of diagnosis even earlier or during fetal development have been documented. Case Presentation: A newborn girl was diagnosed with hydrocephalus during pregnancy. An MRI revealed a large oval hypothalamic process, which suggested a hypothalamic hamartoma. At the age of 2, she experienced alternating crying and laughing seizures, followed by a decrease in visual acuity. Due to involvement of the optic pathways, surgery was not performed and she underwent antiepileptic medicines and gamma knife radiotherapy. At the age of 5 years and 3 months, she presented with breast development and laboratory tests confirmed central precocious puberty. Quarterly injections of GnRH agonists have since been administered with favorable results. Conclusion: Early-diagnosed hypothalamic hamartomas require close monitoring, by an experienced multidisciplinary, to promptly detect and treat potential complications, especially precocious puberty, and prevent any undesirable impact on final height.

关键词： Perinatally-Hypothalamic Hamartoma-Giant-Precocious Puberty

铋纳米颗粒负载的氮掺杂石墨毡用于稳定高效的铁铬液流电池

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新型炭材料（中英文） 2024年第1期39卷 131-141页

作者：车航欣高宇飞杨家辉洪崧郝磊端徐亮 sana Taimoor Alex WRobertson 孙振宇北京化工大学化学工程学院有机-无机复合材料国家重点实验室北京100000 桂林电子科技大学机电工程学院广西桂林541000 Department of Physics University of WarwickCoventry CV47ALUK

铁铬氧化还原液流电池(ICRFB)是一种具有成本效益的可规模化储能系统,其利用资源丰富、低成本的铬和铁作为电解液的活性物质。然而,ICRFB存在Cr^(3+)/Cr^(2+)电化学活性低、负极易产生严重的析氢反应(HER)等问题。本文报道了一种简单的... 详细信息

铁铬氧化还原液流电池(ICRFB)是一种具有成本效益的可规模化储能系统,其利用资源丰富、低成本的铬和铁作为电解液的活性物质。然而,ICRFB存在Cr^(3+)/Cr^(2+)电化学活性低、负极易产生严重的析氢反应(HER)等问题。本文报道了一种简单的合成策略,即通过自聚合和湿化学还原方法结合煅烧处理,在氮掺杂石墨毡(GF)表面沉积了非晶态铋(Bi)纳米颗粒(NPs),其作为ICRFB的负极材料时可展示出高效的电化学性能。生成的BiNPs与H+形成中间体,极大地抑制了HER副反应。此外,Bi的引入和GF表面的N掺杂通过协同作用显著提高了Fe^(2+)/Fe^(3+)和Cr^(3+)/Cr^(2+)的电化学活性,降低了电荷传递电阻,提高了反应传质速率。在不同的电流密度下,经25次循环,库仑效率仍高达97.7%。在60.0 mA cm^(-2)电流密度下,能量效率达到85.8%,超过了许多其他报道的材料。循环100次后容量达到862.7 mAh/L,约为GF的5.3倍。

关键词：铁铬液流电池 Bi 负极氮掺杂石墨毡