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Journal of Earth Science and Engineering 2013年第8期3卷 515-526页

作者： Pedro J. Llanos Gerald R. Hintz martin w. lo James K. Miller Flight Mechanics Section GMV Space and Defence S. A. Tres Cantos Madrid 28760 Spain Astronautical Engineering Department University of Southern California Los Angeles 90089 USA Jet Propulsion Laboratory California Institute of Technology Pasadena 91109 USA Retired Chief Scientist Space Navigation and Flight Dynamics Section KinetX Inc. Simi Valley California 93065 USA

Investigation of new.orbit geometries exhibits a very attractive behavior for a spacecraft to monitor space w.ather coming from the Sun. Several orbit transfer mechanisms are analyzed as potential alternatives to monitor solar activity such as a sub-solar orbit or quasi-satellite orbit and short and long heteroclinic and homoclinic connections betw.en the triangular points L4 and L5 and the collinear point L3 of the CRTBP （circular restricted three-body problem） in the Sun-Earth system. These trajectories could serve as channels through w.ere material can be transported from L5 to L3 by performing small maneuvers at the departure of the Trojan orbit. The size of these maneuvers at L5 is betw.en 299 m/s and 730 m/s depending on the transfer time of the trajectory and does not need any deterministic maneuvers at L3. Our results suggest that material may also be transported from the Trojan orbits to quasi-satellite orbits or even displaced quasi-satellite orbits.

关键词： Quasi-satellite orbits heteroclinic homoclinic Sun-Earth triangular points invariant manifolds solar observations.

A path planning algorithm for a crop monitoring fixed-w.ng unmanned aerial system

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Science China(Information Sciences) 2024年第8期67卷 5-23页

作者： longhao QIAN Yi lok lo Hugh Hong-tao LIU Institute of Aerospace Studies University of Toronto Department of Mechanical Engineering The University of Hong Kong

w.th the grow.ng demand for automation in agriculture, industries increasingly rely on drones to perform crop monitoring and surveillance. In this regard, fixed-w.ng unmanned aerial systems(UASs)are viable platforms for scanning a large crop field, given their payload capacity and range. To achieve maximum coverage w.thout landing for battery replacement, an algorithm for producing a minimal required energy survey path is essential. Hence, an energy-aw.re coverage path planning algorithm is proposed *** constraints for a fixed-w.ng UAS to fly at low.altitudes w.ile achieving full coverage of the crop field are first analyzed. Then, the full path is decomposed into straight-line and U-turn primitives. Finally, an algorithm to calculate a combination of straight-line segments and U-turns is proposed to obtain the path w.th minimum required energy consumption. The genetic algorithm is used to efficiently determine the order of the straight-line paths to traverse. Case studies show.that the proposed algorithm can produce planning results for a convex-polygon-shaped crop field.

关键词： path planning genetic algorithm energy minimization fixed-w.ng UAS aerial survey

Tau in the pancreas:understanding the link betw.en type 2 diabetes mellitus and Alzheimer's disease

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Signal Transduction and Targeted Therapy 2024年第1期9卷 6-7页

作者： w.nlu Li Steffen Tiedt Eng H.lo Neuroprotection Research Laboratories Departments of Radiology and NeurologyMassachusetts General HospitalHarvard Medical SchoolCharlestownMA02129USA Consortium International pour la Recherche Circadienne sur l’AVC(CIRCA) BostonUSA Institute for Stroke and Dementia Research LMU University HospitalLMU MunichMunichGermany

A recent study published in Molecular Psychiatry proposes a cellular mechanism that may contribute to decreased insulin production in individuals w.th type 2 diabetes mellitus(T2DM).1 Using a combination of cell culture experiments,animal models and studies in T2DM patients,the authors show.that an up-regulation of tau inβ-islet cells can inhibit pancreatic insulin secretion through changes in microtubule assembly.

关键词： T2DM Alzheimer tau

Fault Diagnosis Scheme for Railw.y Sw.tch Machine Using Multi-Sensor Fusion Tensor Machine

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Computers, Materials & Continua 2024年第6期79卷 4533-4549页

作者： Chen Chen Zhongw.i Xu Meng Mei Kai Huang Siu Ming lo School of Electronic and Information Engineering Tongji UniversityShanghai201804China Department of Architecture and Civil Engineering City University of Hong KongHong KongChina School of Computer Engineering Jimei UniversityXiamen361021China

Railw.y sw.tch machine is essential for maintaining the safety and punctuality of train operations.A data-driven fault diagnosis scheme for railw.y sw.tch machine using tensor machine and multi-representation monitoring data is developed *** existing methods,this approach takes into account the spatial information of the time series monitoring data,aligning w.th the domain expertise of on-site manual ***,a multi-sensor fusion tensor machine is designed to improve single signal data’s limitations in insufficient ***,one-dimensional signal data is preprocessed and transformed into tw.-dimensional ***,the fusion feature tensor is created by utilizing the images of the three-phase current and employing the CANDE-COMP/PARAFAC(CP)decomposition ***,the tensor learning-based model is built using the extracted fusion feature *** developed fault diagnosis scheme is valid w.th the field three-phase current *** experiment indicates an enhanced performance of the developed fault diagnosis scheme over the current approach,particularly in terms of recall,precision,and F1-score.

关键词： Railw.y sw.tch machine tensor machine fault diagnosis

Refill friction stir spot w.lding (RFSSw.: a review.of processing, similar/dissimilar materials joining, mechanical properties and fracture mechanism

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Journal of Iron and Steel Research International 2024年第8期31卷 1825-1839页

作者： Yun-qiang Zhao Hao-kun Yang Aloshyn Andriia Hong-hang lo Jia-xin Li Guangdong Provincial Key Laboratory of Advanced w.lding Technology China-Ukraine Institute of WeldingGuangdong Academy of SciencesGuangzhou 510000GuangdongChina Smart Manufacturing Division Hong Kong Productivity CouncilHong Kong 999077China E.O.Paton Electric w.lding Institute of National Academy of Sciences of Ukraine Kiev 01001KievanUkraine

Refill friction stir spot w.lding(RFSSw.provides a novel method to join similar and/or dissimilar metallic materials w.thout a key-hole in the center of the *** the key-hole free characterization,the similar/dissimilar RFSSw.joint exhibits remarkable and endurable characteristics,including high shear strength,long fatigue life,and strong corrosion *** the meanw.ile,as the key-hole free joint has different microstructures compared w.th conventional friction stir spot w.lding,thus the RFSSw.joint shall possess different shear and fatigue fracture mechanisms,w.ich needs further *** explore the underlying failure mechanism,the similar/dissimilar metallic material joining parameters and pre-treatment,mechanical properties,as w.ll as fracture mechanisms under this novel technology w.ll be *** details,the w.lding tool design,w.lding parameters setting,and the influence of processing on the lap shear and fatigue properties,as w.ll as the corrosion resistance w.ll be mainly ***,the roadmap of RFFSw.is also discussed.

关键词： Refill friction stir spot w.lding Processing Mechanism Similar materials joining Dissimilar materials joining Microstructure Mechanical property Fracture mechanism

Autolysosomal acidification impairment as a mediator for TNFR1 induced neuronal necroptosis in Alzheimer’s disease

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Neural Regeneration Research 2024年第9期19卷 1869-1870页

作者： Evridiki Asimakidou Richard Reynolds Anna M.Barron Chih Hung lo Department of Clinical Neurosciences University of CambridgeCambridgeUK Department of Brain Sciences Faculty of MedicineImperial College LondonLondonUK Lee Kong Chian School of Medicine Nanyang Technological UniversitySingaporeSingapore

Neuronal necroptosis-an emerging form of regulated cell death associated w.th neuroinflammatory signaling:Alzheimer’s disease(AD)is characterized by the presence of extracellular amyloid-β(Aβ)plaques and intracellular tau neurofibrillary tangles as w.ll as progressive neuronal *** evidence has suggested that prolonged neuroinflammation w.th increased levels of cytokines,arising from neuronal injury,innate immune responses from glial cells,and peripheral inflammation,leads to neuronal death and AD progression.

关键词： Alzheimer death tau Aβ

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Mathematical Modeling of Cell Polarity Establishment of Budding Yeast

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Communications on Applied Mathematics and Computation 2024年第1期6卷 218-235页

作者： Yue Liu Jun Xie Hay-Oak Park w.ng-Cheong lo Department of Mathematics City University of Hong KongTat Chee AvenueKowloonHong KongChina Department of Molecular Genetics The Ohio State UniversityColumbusOHUSA

The budding yeast Saccharomyces cerevisiae is a pow.rful model system for studying the cell polarity *** cell polarization process is regulated by signaling molecules,w.ich are initially distributed in the cytoplasm and then recruited to a proper location on the cell membrane in response to spatial cues or *** of these signaling molecules involves complex regulation,so the mathematical models become a useful tool to investigate the mechanism behind the *** this review.w. discuss how.mathematical modeling has shed light on different regulations in the cell *** also propose future applications for the mathematical modeling of cell polarization and morphogenesis.

关键词： Budding yeast Cdc42 Morphogenesis Septin Mathematical models

How.Can Practitioners Support Citizen Volunteers in Disaster Risk Reduction? Insight from “Good and Ready” in Aotearoa New.Zealand

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International Journal of Disaster Risk Science 2024年第3期15卷 374-387页

作者： lo?c Le Dé Steve Ronoh Ei Mon Thinn Kyu Brigitte Rive School of Public Health and Interdisciplinary Studies Auckland University of Technology Pacific Health Research Centre Auckland University of Technology New.Zealand Red Cross

Global and national policy framew.rks emphasize the importance of people's participation and volunteers' role in disaster risk reduction. w.ile research has extensively focused on volunteers in disaster response and recovery, less attention has been paid on how.organizations involved in disaster risk management can support volunteers in leading and coordinating communitybased disaster risk reduction. In 2019, the New.Zealand Red Cross piloted the Good and Ready initiative in Auckland,Aotearoa New.Zealand, w.th the objective to empow.r local people in resilience building w.th a focus on volunteers and community participation. This research examined the positive and negative outcomes of Good and Ready and investigated volunteers' experiences in the disaster resilience initiative. It involved the codesign of a questionnaire-based survey using participatory methods w.th Good and Ready volunteers, the dissemination of the survey to gather volunteers' view.oints, and a focus group discussion w.th participatory activities w.th Red Cross volunteers. The findings highlight that a key challenge lies in finding a balance betw.en a program that provides flexibility to address contextual issues and fosters communities' ow.ership, versus a prescriptive and standardized approach that leaves little room for creativity and self-initiative. It pinpoints that supporting volunteers w.th technical training is critical but that soft skills training such as coordinating, communicating,or facilitating activities at the local level are needed. It concludes that the sustainability of Good and Ready requires understanding and meeting volunteers' motivations and expectations and that enhancing partnerships w.th local emergency management agencies w.uld strengthen the program.

关键词： Community-based approach Disaster risk reduction New.Zealand Participation Volunteers

Post-fontan circulation hepatocellular carcinoma:Open and laparoscopic hepatectomy

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Hepatobiliary & Pancreatic Diseases International 2024年第1期23卷 90-93页

作者： Karin KY Ho w.ng Hoi She Simon HY Tsang Kevin S lo Tan To Cheung Department of Surgery The University of Hong Kong102 Pok Fu Lam RoadHong KongChina Department of Anaesthesiology Queen Mary Hospital102 Pok Fu Lam RoadHong KongChina

To the Editor:Fontan-associated liver disease show. increasing incidence as advances in pediatric cardiology have prolonged life expectancy in patients w.th single ventricle congenital heart defects[1].Their unique physiology and procedure-related sequelae present an increasingly relevant challenge in hepatic *** hereby reported a series of patients suffering from hepatocellular carcinoma(HCC)w.o successfully underw.nt open and laparoscopic hepatectomy.

关键词： hepatocellular hepatectomy surgery

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Corporate Social Responsibility and Shipping Supply Chain Risks

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Economics w.rld 2024年第3期11卷 145-155页

作者： w.n-Chi lo Ming Chuan University TaoyuanTaiwan

This study aims to investigate w.ether Corporate Social Responsibility(CSR)activities reduce supply chain disruptions by examining the impact of the Suez Canal obstruction on the Ever Given container ship in March *** study conclude that the more responsible companies have higher returns and are less affected by this event than the less responsible companies;the less responsible companies have low.r *** companies w.th better CSR have a low.r impact on their supply chains w.en faced w.th disruptions in the supply chain.

关键词： Suez Canal obstruction corporate social responsibility supply chain risks event study Ever Given container ships