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Identifying disaster-related tweets and their semantic,spatial and temporal context using deep learning,natural language processing and spatial analysis:a case study of Hurricane Irma

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International Journal of Digital Earth 2019年第11期12卷 1205-1229页

作者： Muhammed Ali Sit Caglar Koylu Ibrahim demir Department of Computer Science University of IowaIowa CityIAUSA Department of Geographical and Sustainability Sciences University of IowaIowa CityIAUSA Department of Civil and Environmental Engineering University of IowaIowa CityIAUSA

We introduce an analytical framework for analyzing tweets to(1)identify and categorize fine-grained details about a disaster such as affected individuals,damaged infrastructure and disrupted services;(2)distinguish impact areas and time periods,and relative prominence of each category of disaster-related information across space and *** first identify disaster-related tweets by generating a human-labeled training dataset and experimenting a series of deep learning and machine learning methods for a binary classification of *** employ LSTM(Long Short-Term Memory)networks for the classification task because LSTM networks outperform other methods by considering the whole text structure using long-term semantic word and feature ***,we employ an unsupervised multi-label classification of tweets using Latent Dirichlet Allocation(LDA),and identify latent categories of tweets such as affected individuals and disrupted ***,we employ spatiallyadaptive kernel smoothing and density-based spatial clustering to identify the relative prominence and impact areas for each information category,*** Hurricane Irma as a case study,we analyze over 500 million keyword-based and geo-located collection of tweets before,during and after the *** results highlight potential areas with high density of affected individuals and infrastructure damage throughout the temporal progression of the disaster.

关键词： Social sensing Twitter deep learning natural language processing spatial analysis hurricane

超晶格La-Mg/Y-Ni复合储氢合金晶体结构及性能研究进展

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复合材料学报 2024年第3期41卷 1204-1214页

作者：张晓杰田晓张颖韩家乐杨艳春塔娜内蒙古师范大学物理与电子信息学院呼和浩特010022 内蒙古师范大学稀土功能新能源储能材料内蒙古自治区工程研究中心呼和浩特010022 内蒙古师范大学功能材料物理与化学自治区重点实验室呼和浩特010022

超晶格La-Mg/Y-Ni复合储氢合金具有放电容量大、能量密度高和成本低等优点,是一种重要的氢能存储和转换材料,目前主要用做镍氢电池负极材料和直接硼氢化物燃料电池阳极催化剂。La-Mg-Ni复合合金最初是在La-Ni基储氢合金的基础上,通过用... 详细信息

超晶格La-Mg/Y-Ni复合储氢合金具有放电容量大、能量密度高和成本低等优点,是一种重要的氢能存储和转换材料,目前主要用做镍氢电池负极材料和直接硼氢化物燃料电池阳极催化剂。La-Mg-Ni复合合金最初是在La-Ni基储氢合金的基础上,通过用部分Mg替代La而发展起来的。由于La-Mg-Ni复合合金中金属Mg熔点、沸点低,易挥发,导致采用常规熔炼法很难制备;同时合金中的Mg在碱性电解液中容易腐蚀、氧化,导致合金的循环稳定性差。为克服La-Mg-Ni复合合金制备困难和循环稳定性差等问题,研究者又在La-Ni基储氢合金的基础上,通过用部分Y替代La开发出了La-Y-Ni合金。La-Mg-Ni和La-Y-Ni复合合金具有非常相似的超晶格结构,均能表现出很好的储氢性能,均属于同一类新型超晶格结构储氢合金。本文对La-Mg/Y-Ni储氢合金近20多年的研究成果进行了梳理。本文首先介绍超晶格La-Mg-Ni和La-Y-Ni复合合金的相结构组成及相结构的演变规律,同时分析了Mg元素和Y元素部分替代La元素分别对La-Mg/Y-Ni合金结构和性能的影响,然后讨论了La-Mg/Y-Ni复合合金中的相结构对合金性能的影响。最后,指出了超晶格La-Mg/Y-Ni复合储氢合金未来所面临的挑战和发展方向。

关键词：储氢材料 La-Mg-Ni复合储氢合金 La-Y-Ni复合储氢合金相结构电化学性能

波联国际泽被人间--追忆医学超声学先驱王威琪院士

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声学学报 2024年第3期49卷 361-365页

作者：汪源源他得安马作鹏复旦大学生物医学工程系上海200438 人民网上海频道上海200120

“波联国际,泽被人间。”1988年,美国,华盛顿。世界医学生物超声联合会授予一位中国科学家、复旦大学教师先驱者奖(Pioneer Award),时任复旦大学校长苏步青院士闻讯立即亲笔提写这八字横幅,以示祝贺。

关键词：苏步青复旦大学校长医学生物王威琪院士先驱者

Epidemiology, Clinical Features and Antifungal Resistance Profile of Candida auris in Africa: Systematic Review

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Journal of Biosciences and Medicines 2024年第1期12卷 126-149页

作者： Isidore Wendkièta Yerbanga Seydou Nakanabo Diallo Toussaint Rouamba Delwendé Florence Ouedraogo Katrien Lagrou Rita Oladele Jean-Pierre Gangneux Olivier Denis Hector Rodriguez-Villalobos Isabel Montesinos Sanata Bamba Centre Hospitalier Universitaire Régional de Ouahigouya Ouahigouya Burkina Faso Ecole Doctorale des Sciences De la Santé Université Nazi Boni Bobo-Dioulasso Burkina Faso Centre Muraz/Institut National de Santé Publique Bobo-Dioulasso Burkina Faso Clinical Research Unit of Nanoro Institute for Research in Health Sciences National Center for Scientific and Technological Research Ouagadougou Burkina Faso Department of Microbiology Immunology and Transplantation KU Leuven Leuven Belgium and Department of Laboratory Medicine and National Reference Center for Mycosis Excellence Center for Medical Mycology (ECMM) University Hospitals Leuven Leuven Belgium College of Medicine University of Lagos Lagos Nigeria Univ Rennes CHU Rennes Inserm Irset (Institut de recherche en santé environnement et travail) European ECMM Excellence Center in Medical Mycology Université de Rennes Rennes France Department of Microbiology CHU Namur site-Godinne Université Catholique de Louvain Yvoir Belgium Ecole de Santé Publique Université Libre de Bruxelles Brussels Belgium Department of Microbiology Cliniques Universitaires Saint-Luc—Université Catholique de Louvain Bruxelles Belgium Centre Hospitalier Universitaire Sour? Sanou Bobo-Dioulasso Burkina Faso

Candida auris since it discovery in 2009 is becoming a severe threat to human health due to its very quickly spread, its worldwide high resistance to systemic antifungal drugs. In resource-constrained settings where several conditions are met for its emergence and spread, this worrisome fungus could cause large hospital and/or community-based outbreaks. This review aimed to summarize the available data on C. auris in Africa focusing on its epidemiology and antifungal resistance profile. Major databases were searched for articles on the epidemiology and antifungal resistance profile of C. auris in Africa. Out of 2,521 articles identified 22 met the inclusion criteria. In Africa, nearly 89% of African countries have no published data on C. auris. The prevalence of C. auris in Africa was 8.74%. The case fatality rate of C. auris infection in Africa was 39.46%. The main C. auris risk factors reported in Africa were cardiovascular disease, renal failure, diabetes, HIV, recent intake of antimicrobial drugs, ICU admissions, surgery, hemodialysis, parenteral nutrition and indwelling devices. Four phylogenetic clades were reported in Africa, namely clades I, II, III and IV. Candida auris showed a pan-African very high resistance rate to fluconazole, moderate resistance to amphotericin B, and high susceptibility to echinocandins. Finally, C. auris clade-specific mutations were observed within the ERG2, ERG3, ERG9, ERG11, FKS1, taC1b and MRR1 genes in Africa. This systematic review showed the presence of C. auris in the African continent and a worrying unavailability of data on this resilient fungus in most African countries.

关键词： Africa Antifungal Resistance Candida auris Clinical Features Phylogenetic Clades

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船舶螺旋桨推力的在线高精度辨识方法

中国舰船研究 2024年第3期19卷 310-318页

作者：马相龙吴昊邹冬林薛林塔娜饶柱石上海船舶设备研究所上海200031 上海交通大学机械系统与振动全国重点实验室上海200240 上海交通大学振动、冲击、噪声研究所上海200240 高新船舶与深海开发装备协同创新中心上海200240

[目的]螺旋桨推力在轴系上产生的微弱形变信号易被干扰噪声所淹没,导致难以准确测量其推力,故提出一种在低信噪比下仍具有很高精度的螺旋桨推力测量方法。[方法]综合考虑测量数据误差的影响以及数据中潜藏的力学机制,基于Kalman滤波结... 详细信息

[目的]螺旋桨推力在轴系上产生的微弱形变信号易被干扰噪声所淹没,导致难以准确测量其推力,故提出一种在低信噪比下仍具有很高精度的螺旋桨推力测量方法。[方法]综合考虑测量数据误差的影响以及数据中潜藏的力学机制,基于Kalman滤波结合推力–位移状态方程建立轴系推力辨识模型,并以恒定转速、变转速及低频波动转速3种工况为例开展轴系推力测量研究,分析不同信噪比下该方法的推力辨识精度与鲁棒性。[结果]研究结果表明,当信噪比仅为20 dB时,推力辨识的最大相对误差仅为3.56%,验证了其在低信噪比下的高精度辨识能力与鲁棒性。[结论]研究成果可为实船环境下螺旋桨推力及轴系状态的在线实时高精度监测提供参考。

关键词： Kalman滤波推力辨识推进轴系位移测量在线监测

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正交匹配追踪优化稀疏频散Radon变换多模式导波分离方法

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声学学报 2024年第3期49卷 371-380页

作者：郑书航陈洪磊凌非尧许凯亮他得安复旦大学信息科学与工程学院生物医学工程系上海200438 复旦大学集成芯片与系统全国重点实验室上海201203 复旦大学义乌研究院义乌322000 复旦大学工程与应用技术研究院生物医学工程技术研究所上海200433

原始频散Radon变换(DRT)方法中的有限孔径效应以及算子非正交性影响了DRT导波信号参数提取的精度,因此提出了一种稀疏频散Radon变换方法以实现更精确的导波混叠模式分离和参数估计。该方法基于导波信号的参数域稀疏性,引入正交匹配追踪... 详细信息

原始频散Radon变换(DRT)方法中的有限孔径效应以及算子非正交性影响了DRT导波信号参数提取的精度,因此提出了一种稀疏频散Radon变换方法以实现更精确的导波混叠模式分离和参数估计。该方法基于导波信号的参数域稀疏性,引入正交匹配追踪算法构造代价函数,经多次迭代在频散Radon域中获得稀疏能量谱,可精确分离阵列导波信号中的混叠模式并去噪。对不同信噪比下各模式仿真信号,稀疏DRT方法的信号重建误差较原始频散Radon变换方法下降51.1%。仿真和实验验证了所提算法在导波模式参数提取和混合模式分离方面的可靠性。

关键词：超声导波模式分离频散Radon变换正交匹配追踪

推进轴系弯-纵耦合非线性效应对推力测量精度影响研究

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船舶力学 2024年第7期28卷 1063-1072页

作者：邹冬林马相龙吴昊薛林杨宇泽塔娜饶柱石上海交通大学振动、冲击、噪声研究所机械系统与振动国家重点实验室上海200240 上海船舶设备研究所上海200031 高新船舶与深海开发装备协同创新中心上海200240

高精度监测推进轴系推力对船舶快速性预报、船-机-桨优化匹配及轴系健康管理等具有重要意义。然而,对于超长推进轴系,由于其跨距大、细长比(轴系半径与长度之比)小、且承受推力大,此时轴系将产生严重弯-纵耦合非线性变形。这将对基于应... 详细信息

高精度监测推进轴系推力对船舶快速性预报、船-机-桨优化匹配及轴系健康管理等具有重要意义。然而,对于超长推进轴系,由于其跨距大、细长比(轴系半径与长度之比)小、且承受推力大,此时轴系将产生严重弯-纵耦合非线性变形。这将对基于应变或变形位移等形变信息来测量推力的方法产生重要影响。因此,本文研究推进轴系弯-纵耦合非线性效应对推力测量精度的影响。考虑Von Karman非线性位移-应变关系,利用Hamilton变分原理结合有限元方法建立推进轴系非线性力学模型,研究弯-纵耦合效应对轴系变形位移和应变的影响规律,以及由此引起的推力测量误差。研究结果表明:在低转速时,轴系弯-纵耦合效应较弱,对推力测量影响很小;高转速时,忽略轴系弯-纵耦合效应将引起较大测量误差(240 r/min时,误差可达13.95%);测点越靠近螺旋桨,弯-纵耦合效应越强,推力测量误差越大,因此将测点布置在轴系前端推力轴承附近可有效减少轴系弯-纵耦合效应引起的测量误差。研究结果对跨度大、细长比小的超长轴系推力测量有指导意义。

关键词：推进轴系推力测量非线性弯-纵耦合有限元法

Phytochemical Composition and Insecticidal Property of Native Plants against the Cowpea Weevil Callosobruchus maculatus Fab. (Coleoptera: Bruchidae) for Natural Preservation of Cowpea Seeds

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Advances in Entomology 2024年第1期12卷 56-66页

作者： Elias Mano Rabièta Simde Koï Wenceslas Kam Nadjatou Ouédraogo Désiré Dramane Abdoul Khader Sanou Rasmané Abdou Ouédraogo Boubakar Ouattara Pierre Alexandre Eric Djifaby Sombié Souleymane Nacro Laboratory of Natural Substances and Technologies of Natural Products and the Environment (LABTECH-PRONE) Institute of Research in Applied Sciences and Technologies (IRSAT) Ouagadougou Burkina Faso Central Horticulture Laboratory of the Regional Center of Excellence in Fruits and Vegetables of Bobo-Dioulasso Institute of Environment and Agricultural Research (INERA) Bobo Dioulasso Burkina Faso Department of Animal Biology and Physiology University Joseph Ki-Zerbo Ouagadougou Burkina Faso National Agricultural Training School of Matourkou (ENAFA) Bobo Dioulasso Burkina Faso Institute of Rural Development (IDR) Nazi Boni University Bobo Dioulasso Burkina Faso

About 80% of cowpea seeds are lost along with 30% of their weight after six months of unprotected storage due to attacks by Callosobruchus maculatus. This study aimed at evaluating the effect of applying bioinsecticides on the biological parameters of C. maculatus to reduce its damage to cowpea stocks. Four treatments including an untreated control and three doses of powdery extracts of C. nigricans, Z. zanthoxyloides and H. suaveolens, were compared in a Fischer block with four completely randomized repetitions. One hundred undamaged cowpea seeds were mixed with doses of each extract in Petri dishes and then fed as food substrates to ten pairs of C. maculatus for eight days. The extracts of H. suaveolens, C. nigricans and Z. zanthoxyloides all contain active ingredients including polyphenols, flavonoids, anthocyanins and alkaloids, etc. The extract of Z. zanthoxyloides was found to be more active on adults (100.00% mortality) followed by C. nigricans (98.75% mortality) and H. suaveolens (97.50% mortality) at 80 mg/g. Fecundity per female decreased significantly in the treated batches of 13.82 eggs for H. suaveolens at 10.12 eggs for C. nigricans at a dose of 80 mg/g. Germination rate of seeds was statistically raised to 100% at 60 and 80 mg/g by C. nigricans powder and lowered to 83.00% at 20 mg/g by Z. zanthoxyloides extracts. The application of Z. zanthoxyloides extract would be a less expensive alternative for the sustainable management of C. maculatus in cowpea stocks.

关键词： Cassia nigricans Hyptis suaveolens Zanthoxylum zanthoxyloides Biological Activities Vigna unguiculata Pest Burkina Faso

Automated integration of real-time and non-real-time defense systems

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Defence Technology（防务技术） 2021年第2期17卷 657-670页

作者： Emre Dalkıran Tolga Onel Okan Topçu Kadir Alpaslan demir Barbaros Naval Science and Engineering Institute Turkish Naval AcademyNational Defense UniversityTuzlaIstanbul34942Turkey Department of Computer Engineering Turkish Naval AcademyNational Defense UniversityTuzlaIstanbul34942Turkey Department of Computer Engineering Middle East Technical University Northern Cyprus CampusKalkanliGuzelyurtMersin 1099738Turkey Institute of Social Sciences Gebze Technical UniversityGebzeKocaeli41400Turkey

Various application domains require the integration of distributed real-time or near-real-time systems with non-real-time *** cities,smart homes,ambient intelligent systems,or network-centric defense systems are among these application *** Distribution Service(DDS)is a communication mechanism based on Data-Centric Publish-Subscribe(DCPS)*** is used for distributed systems with real-time operational *** Message Service(JMS)is a messaging standard for enterprise systems using Service Oriented Architecture(SOA)for non-real-time *** allows Java programs to exchange messages in a loosely coupled *** also supports sending and receiving messages using a messaging queue and a publish-subscribe *** this article,we propose an architecture enabling the automated integration of distributed real-time and non-real-time *** test our proposed architecture using a distributed Command,Control,Communications,Computers,and Intelligence(C4I)*** system has DDS-based real-time Combat Management System components deployed to naval warships,and SOA-based non-real-time Command and Control components used at *** proposed solution enables the exchange of data between these two systems *** compare the proposed solution with a similar *** solution is superior in terms of automation support,ease of implementation,scalability,and performance.

关键词： Systems integration System of systems Systems engineering Software engineering C4I systems Defense systems Data distribution service DDS integration Java message service JMS