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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 weather 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 between 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 where 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 between 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.

Analysis of the Oscillatory Flows of Multiple Shock.Waves in a Constant Area Duct

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Journal of Thermal Science 2024年第3期33卷 794-806页

作者： k.james Jintu k.M Heuy Dong Department of Mechanical Engineering Andong National UniversityAndong36729Republic of Korea CAD-IT k.rea Co. Ltd.Seoul08591Republic of Korea

The oscillatory response of multiple shock.waves to downstream perturbations in a supersonic flow is studied numerically in a rectangular *** shock.waves are formed inside the duct at a shock.Mach number of *** duct has an exit height of H,and the effect of duct resonance on multiple shock.oscillations is investigated by attaching exit ducts of lengths 0H,50H,and *** downstream disturbance frequency varied from 10 Hz to 200 Hz to explore the oscillation characteristics of the multiple shock.*** oscillatory response of shock.waves under self-excited and forced oscillation conditions are analyzed in terms of wall static pressure,shock.train leading-edge location,shock.train length,and the size of the separation *** extent of the initial shock.location increases with an increase in exit duct length for the self-excited oscillation *** analysis of the shock.train leading edge and the spectral analysis of wall static pressure variations are *** variation in the shock.train length is analyzed using the pressure ratio method for self-excited as well as forced *** RMS amplitude of the normalized shock.train length(ζ_(ST))increases with an increase in the exit duct length for the self-excited oscillation *** the downstream perturbation frequency is increased,ζ_(ST)is decreased for exit duct *** all exit duct designs and downstream forcing frequencies,the size of the separation bubble grows and shrink. during the shock.oscillations,demonstrating the dependence on duct resonance and forced oscillations.

关键词： shock.train downstream disturbance supersonic flow shock.wave boundary layer interaction duct resonance flow separation

Commentary on“Incidence of urinary incontinence following endoscopic laser enucleation of the prostate by en-bloc and non-en-bloc techniques:a multicenter,real-world experience of 5068 patients”

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Asian Journal of Andrology 2024年第3期26卷 333-334页

作者： james F Jiang Narmina k.Onder Ak.il k.Das Department of Urology University of California Irvine Orange CA 92868 USA.

Laser enucleation of the prostate is a proven and effectivesize-independent method for the surgical management of symptomaticbenign prostatic hyperplasia(BPH)and is considered as the“goldstandard”by many *** major hurdles that stand in theway of this becoming a universally used procedure for BPH are thesteep learning curve associated with mastering the procedure andpossibility of perioperative transient *** advances inteaching methodologies have helped tack.e the difficulty in learning itand increased the number of urologists utilizing the *** forthe second hurdle,transient incontinence rates postlaser enucleationof the prostate have improved with the advent of newer techniques *** et al.1 assesses the incidence of stress,urge,andmixed urinary incontinence following laser enucleation of the prostateby comparing en-bloc and non-en-bloc techniques in a multicenterseries of 5068 men with BPH.

关键词： urinary incontinence transient

Insm1:orchestrating cellular mimicry in the thymus medulla

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Cellular & Molecular Immunology 2024年第4期21卷 414-416页

作者： k.D.james J.E.Cowan UCL Institute of Immunity and Transplantation The Pears BuildingRowland Hill StreetLondonNW32PPUK

The thymus is the primary production site for a functional and self-tolerant T-cell *** establishment of immune tolerance is mediated by the generation and presentation of tissue-restricted self-antigens(TRAs)by medullary thymic epithelial cells(mTECs),which screen T-cell receptors for self-reactivity to eliminate autoreactive T *** studies have extended our understanding of mTEC heterogeneity by examining the mechanisms by which mTECs mimic the peripheral self[1].

关键词： medullary eliminate restricted

Exposure of juvenile Chinook.salmon to effluent from a large urban wastewater treatment *** *** responses

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Aquaculture and Fisheries 2024年第3期9卷 355-366页

作者： Suzanne C.Ball james P.Meador C.Andrew james Jenifer k.McIntyre Washington State University School of the EnvironmentPuyallup Research and Extension Center2606 W Pioneer AvePuyallupWA98371USA Dept.of Environmental and Occupational Health Sciences School of Public Health4225 Roosevelt Way NESuite 100SeattleWA98105-6099USA University of Washington Tacoma Center for Urban Waters326 East D StreetTacomaWA98421-1801USA

Wastewater treatment plants release complex mixtures of chemicals into the aquatic environment as wastewater effluent(WWE);however,the effects of these mixtures are still poorly *** salmon(Oncorhynchus tshawytscha)are a culturally important species in the Pacific Northwest and are a vital food resource for southern resident k.ller whales(Orcinus orca)that are listed as‘critically endangered’under the *** Species Act(ESA).Chinook.populations have declined drastically in this region and have failed to show significant recovery despite regional-to-federal efforts,resulting in many populations being listed as threatened under the *** source of stress to juvenile Chinook.is chemical pollution from WWE during their outmigration along river corridors and residency in *** this study,we investigated effects of WWE on juvenile Chinook.health in a ten-day exposure to dilutions of WWE from 0.1%to 20%.At the end of the exposure,we measured endpoints associated with endocrine disruption,brain function,osmoregulation,stress,and *** to WWE significantly(α=0.1 for all analyses)induced vitellogenesis,indicating endocrine system *** saw significant reductions in plasma glucose,an indication of stress,and brain Na+/k.-ATPase(Nk.)activity,an enzyme essential for neuronal ***,metabolism was affected as evidenced by altered total protein,cholesterol,and albumin in plasma,a drastic decrease in whole body lipid content,and a significant increase in visible liver *** compared contaminant concentrations in exposure water with effects concentrations from the literature for chemicals k.own to induce vitellogenin or inhibit brain *** most contaminants,concentrations in exposure waters were several orders of magnitude below effects concentrations in the *** exception was estrogenic hormones,which were detected at similar concentrations in this study compared to concentrations in other studies tha

关键词： Wastewater effluent Chinook.salmon Toxicity Sodium potassium ATPase Vitellogenin Physiology Metabolism Glucose

Exposure of juvenile Chinook.salmon to effluent from a large urban wastewater treatment *** *** profiling

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Aquaculture and Fisheries 2024年第3期9卷 367-377页

作者： james P.Meador Suzanne C.Ball C.Andrew james Jenifer k.McIntyre Dept.of Environmental and Occupational Health Sciences School of Public Health4225 Roosevelt Way NESuite 100SeattleWA98105-6099USA Washington State University School of the EnvironmentPuyallup Research and Extension Center2606 W Pioneer AvePuyallupWA98371USA University of Washington Tacoma Center for Urban Waters326 East D StreetTacomaWA98421-1801USA

Targeted metabolomic analysis was conducted on juvenile Chinook.salmon exposed for 10 days to wastewater effluent(WWE)from a large urban treatment *** included five dilutions of WWE(20%,5.3%,1.4%,0.4%,and 0.1%)and a control with 7 replicates per *** was extracted from fish and analyzed via liquid chromatography–mass spectrometry(LC-MS)for 361 endogenous metabolites,of which 185 were ***-versus-treatment comparisons identified several metabolites that were associated with altered biochemical pathways observed for all treatments,including several that are important for energy generation and *** altered pathways are crucial for fish health and may be an early indicator of potential adverse effects on growth,reproduction,behavior,and immune *** ocean-type Chinook.salmon spend several days to week. in the nearshore estuary where they may encounter high concentrations of WWE *** are exposed to a wide range of potent pharmaceuticals,personal care products,and industrial compounds from WWE that have the potential to affect physiological homeostasis and disrupt their normal life cycle.

关键词： Wastewater effluent Metabolomics Physiology Chinook.salmon Pharmaceuticals Metabolic pathways Estuary

Time-Aware LSTM Neural Network. for Dynamic Personalized Recommendation on Business Intelligence

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Tsinghua Science and Technology 2024年第1期29卷 185-196页

作者： Xuan Yang james A.Esquivel Graduate School Angeles University FoundationAngeles City 2009Philippines Shandong Provincial University Laboratory for Protected Horticulture Weifang University of Science and TechnologyWeifang 262700China

Personalized recommendation plays a critical role in providing decision-mak.ng support for product and service analysis in the field of business ***,deep neural network.based sequential recommendation models gained considerable ***,existing approaches pay litle attention to users'dynamically evolving interests,which are influenced by product attributes,especially product *** overcome these challenges,we propose a dynamic personalized recommendation model:***,we first embed product information and attribute information into a unified data ***,we exploit long short-term memory(LsTM)network. to characterize sequential behavior over multiple time periods and seize evolving interests by hierarchical LSTM ***,similarity values between users are measured through pairwise interest features,and personalized recommendation lists are generated.A series of experiments reveal the superiority of the proposed method compared withotheradvanced methods.

关键词： personalized recommendations evolving interests embedding LsTM network.

Probing turbulence in galaxies with fast radio burst scintillation

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Science China(Physics,Mechanics & Astronomy) 2024年第1期67卷 177-178页

作者： james M.Cordes Department of Astronomy the Cornell Center for Astrophysics and Planetary ScienceCornell UniversityIthaca NY 14853USA

Interstellar scintillation(ISS)is a well-k.own phenomenon observed from pulsars in the Milk. *** comprises intensity variations *** and frequency caused by constructive and destructive interference from multipath propagation,which is due to diffraction from fluctuations in electron density in the interstellar medium(ISM)on scales as small as~100 *** density fluctuations appear to be part of a turbulence process combined with discrete structures in electron density from other astrophysical processes;together these fluctuations extend to scales of pc or larger.

关键词： scales galaxies turbulence

LSTM Network.Based Adaptation Approach for Dynamic Integration in Intelligent End-Edge-Cloud Systems

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Tsinghua Science and Technology 2024年第4期29卷 1219-1231页

作者： Xuan Yang james A.Esquivel Graduate School Angeles University FoundationAngeles City 2009Philippinesand also with Shandong Provincial University Laboratory for Protected HorticultureWeifang University of Science and TechnologyWeifang 262700China Graduate School Angeles University FoundationAngeles City 2009Philippines

Edge computing, which migrates compute-intensive task. to run on the storage resources of edge devices, efficiently reduces data transmission loss and protects data privacy. However, due to limited computing resources and storage capacity, edge devices fail to support real-time streaming data query and processing. To address this challenge, first, we propose a Long Short-Term Memory (LSTM) network.based adaptive approach in the intelligent end-edge-cloud system. Specifically, we maximize the Quality of Experience (QoE) of users by automatically adapting their resource requirements to the storage capacity of edge devices through an event mechanism. Second, to reduce the uncertainty and non-complete adaption of the edge device towards the user’s requirements, we use the LSTM network.to analyze the storage capacity of the edge device in real time. Finally, the storage features of the edge devices are aggregated to the cloud to re-evaluate the comprehensive capability of the edge devices and ensure the fast response of the user devices during the dynamic adaptation matching process. A series of experimental results show that the proposed approach has superior performance compared with traditional centralized and matrix decomposition based approaches.

关键词： quality of experience data query end-edge-cloud Long Short-Term Memory(LSTM)network.

Characterization and Modeling of Mechanical Properties of Additively Manufactured Coconut Fiber-Reinforced Polypropylene Composites

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Advances in Materials Physics and Chemistry 2024年第6期14卷 95-112页

作者： George Mosi Bernard W. Ik.a Samuel k. k.bini james W. Mwangi Department of Mechatronic Engineering Jomo Kenyatta University of Agriculture and Technology Juja Kenya

In the face of the increased global campaign to minimize the emission of greenhouse gases and the need for sustainability in manufacturing, there is a great deal of research focusing on environmentally benign and renewable materials as a substitute for synthetic and petroleum-based products. Natural fiber-reinforced polymeric composites have recently been proposed as a viable alternative to synthetic materials. The current work.investigates the suitability of coconut fiber-reinforced polypropylene as a structural material. The coconut fiber-reinforced polypropylene composites were developed. Samples of coconut fiber/polypropylene (PP) composites were prepared using Fused Filament Fabrication (FFF). Tests were then conducted on the mechanical properties of the composites for different proportions of coconut fibers. The results obtained indicate that the composites loaded with 2 wt% exhibited the highest tensile and flexural strength, while the ones loaded with 3 wt% had the highest compression strength. The ultimate tensile and flexural strength at 2 wt% were determined to be 34.13 MPa and 70.47 MPa respectively. The compression strength at 3 wt% was found to be 37.88 MPa. Compared to pure polypropylene, the addition of coconut fibers increased the tensile, flexural, and compression strength of the composite. In the study, an artificial neural network.model was proposed to predict the mechanical properties of polymeric composites based on the proportion of fibers. The model was found to predict data with high accuracy.

关键词： Additive Manufacturing Artificial Neural Network Mechanical Properties Natural Fibers Polypropylene