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Optimal impulsive rendezvous for highly elliptical orbits using linear primer vector theory

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Chinese Journal of Aeronautics 2024年第3期37卷 194-207页

作者： Maozhang zheng Jianjun luo Zhaohui DANG National Key Laboratory of Aerospace Flight Dynamics Northwestern Polytechnical UniversityXi’an 710072China

In this paper,minimum-fuel rendezvous is investigated for the case in which the reference orbit is highly *** this end,the well-known Tschauner-Hempel equations are used to describe the relative motions between rendezvous spacecraft and the ***’s primer vector theory is then applied on this linear but time-varying *** analytical solution of the required primer vector for this problem is then derived by using a recently developed *** the existing non-optimal solutions which don’t satisfy the conditions,the methods are further designed to improve the performance by shifting impulses or adding a new ***,two algorithms are developed for free-impulse time-fixed rendezvous *** first algorithm can determine the globally optimal trajectory with the optimal number of *** second one enables for fast trajectory *** proposed algorithms have been successfully applied to coplanar and three-dimensional rendezvous problems in which the target is flying on highly elliptical orbits.

关键词： Orbital transfer Optimal trajectory Primer vector Tschauner-Hempel equations Globally planning Fast planning

Morphology Study for GeV Emission of Nearby Supernova Remnant G332.5-5.6

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Research in Astronomy and Astrophysics 2024年第4期24卷 134-140页

作者： Ming-Hong luo Qing-Wen Tang xiu-Rong Mo Department of Physics School of Physics and Materials ScienceNanchang UniversityNanchang 330031China

A spatial template is important to study nearby supernova remnants(SNRs).For SNR G332.5-5.6,we report a Gaussian disk with a radius of about 1°.06 to be a potential good spatial model in the γ-ray *** this new Gaussian disk,its GeV lightcurve shows a significant variability of about seven *** γ-ray observations of this SNR could be explained well either by a leptonic model or a hadronic model,in which a flat spectrum for the ejected electrons/protons is required.

关键词： ISM:supernova remnants gamma rays:ISM

HetNets Under Decoupled Uplink and Downlink Access with UE Random Discontinuous Transmission: Local Delay and Energy Efficiency

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China Communications 2024年第3期21卷 205-216页

作者： Zhang Yue zheng Fuchun luo Jingjing School of Electronic and Information Engineering Harbin Institute of Technology(Shenzhen)Shenzhen 518055China

Due to the limited uplink capability in heterogeneousnetworks (HetNets), the decoupled uplinkand downlink access (DUDA) mode has recently beenproposed to improve the uplink performance. In thispaper, the random discontinuous transmission (DTX)at user equipment (UE) is adopted to reduce the interferencecorrelation across different time slots. By utilizingstochastic geometry, we analytically derive themean local delay and energy efficiency (EE) of an uplinkHetNet with UE random DTX scheme under theDUDA mode. These expressions are further approximatedas closed forms under reasonable *** results reveal that under the DUDA mode, there isan optimal EE with respect to mute probability underthe finite local delay constraint. In addition, with thesame finite mean local delay as under the coupled uplinkand downlink access (CUDA) mode, the HetNetsunder the DUDA mode can achieve a higher EE witha lower mute probability.

关键词： decoupled uplink and downlink access(DUDA) heterogeneous networks(HetNets) random discontinuous transmission(DTX) stochastic geometry

Robust Distributed Model Predictive Control for Formation Tracking of Nonholonomic Vehicles

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IEEE/CAA Journal of Automatica Sinica 2024年第2期11卷 560-562页

作者： Zhigang luo Bing Zhu Jianying zheng Zewei zheng School of Automation Science and Electrical Engineering Beihang UniversityBeijing 100191China

Dear Editor,This letter proposes a robust distributed model predictive control(MPC) strategy for formation tracking of a group of wheeled vehicles subject to constraints and disturbances. Formation control has attract... 详细信息

关键词： letter constraints searching

Progress in research on the exploration and evaluation of deep geothermal resources in the Fujian-Guangdong-Hainan region,China

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Energy Geoscience

Energy Geoscience 2024年第2期5卷 1-13页

作者： Herong zheng Jun luo Petroleum Exploration and Production Research Institute SINOPECBeijing 102206China

Deep geothermal resources in the Fujian-Guangdong-Hainan region,China,offer significant potential for sustainable *** diverse igneous rock formations along the southeast coast present intricate geological challenges that impede exploration and evaluation *** this study,we address critical concerns related to the Fujian-Guangdong-Hainan region's deep geothermal resources,encompassing heat source composition,formation conditions,strategic favorable areas,and exploration *** methods involve the analysis of regional geothermal reservoirs and cap *** findings include:the primary heat sources in the Fujian-Guangdong-Hainan region consist of the radioactive heat generation from granites in the crust,heat conduction in the mantle,and,in specific areas like Yangjiang and Shantou,melts within the middle and lower crust;the deep,high-temperature geothermal resources in the region predominantly reside in basins'depressed *** areas are characterized by the confluence of triple heat sources:heat from the Earth's crust,mantle,and other supplementary sources;our analysis led to the identification of three strategic areas favorable for deep geothermal resources in the Fujian-Guangdong-Hainan *** are the Beibu Gulf Basin's continental area,the Yuezhong Depression,and the Fuzhou-Zhangzhou area.

关键词： Deep geothermal resources Geology of geothermal energy Strategic selection

Emerging delivery systems based on aqueous two-phase systems:A review

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Acta Pharmaceutica Sinica B 2024年第1期14卷 110-132页

作者： Yaowen Zhang Yankun luo Jingqi Zhao Wenzhuo zheng Jun Zhan Huaping zheng Feng luo State Key Laboratory of Oral Diseases National Clinical Research Center for Oral DiseasesWest China School of StomatologySichuan UniversityChengdu 610041China Department of Obstetrics and Gynecology West China Second University HospitalSichuan UniversityChengdu 610041China Key Laboratory of Birth Defects and Related Diseases of Women and Children(Sichuan University) Ministry of EducationChengdu 610041China Department of Dermatology Rare Diseases CenterInstitutes for Systems GeneticsFrontiers Science Center for Disease-related Molecular NetworkWest China HospitalSichuan UniversityChengdu 610041China Department of Prosthodontics West China School of StomatologySichuan UniversityChengdu 610041China

The aqueous two-phase system(ATPS)is an all-aqueous system fabricated from two immiscible aqueous *** is spontaneously assembled through physical liquid-liquid phase separation(LLPS)and can create suitable templates like the multicompartment of the intracellular *** structures containing multiple compartments make it possible to endow materials with advanced *** to the properties of ATPSs,ATPS-based drug delivery systems exhibit excellent biocompatibility,extraordinary loading efficiency,and intelligently controlled content release,which are particularly advantageous for delivering drugs in ***,we will systematically review and evaluate ATPSs as an ideal drug delivery *** on the basic mechanisms and influencing factors in forming ATPSs,the transformation of ATPSs into valuable biomaterials is ***,we concentrate on the most recent cutting-edge research on ATPS-based delivery ***,the potential for further collaborations between ATPS-based drug-carrying biomaterials and disease diagnosis and treatment is also explored.

关键词： Aqueous two-phase systems Drug delivery systems Biomaterials Microcapsules Microparticles Cell therapy Cancer treatment Organ regeneration

Spatiotemporal Prediction of Urban Traffics Based on Deep GNN

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Computers, Materials & Continua 2024年第1期78卷 265-282页

作者： Ming luo Huili Dou Ning zheng School of Computer Science Hangzhou Dianzi UniversityHangzhou310018China Zhejiang Institute of Communications Hangzhou310012China School of Cyberspace Security Hangzhou Dianzi UniversityHangzhou310018China

Traffic prediction already plays a significant role in applications like traffic planning and urban management,but it is still difficult to capture the highly non-linear and complicated spatiotemporal correlations of traffic *** well as to fulfil both long-termand short-termprediction objectives,a better representation of the temporal dependency and global spatial correlation of traffic data is *** order to do this,the Spatiotemporal Graph Neural Network(S-GNN)is proposed in this research as amethod for traffic *** S-GNN simultaneously accepts various traffic data as inputs and investigates the non-linear correlations between the *** terms of modelling,the road network is initially represented as a spatiotemporal directed graph,with the features of the samples at the time step being captured by a convolution *** order to assign varying attention weights to various adjacent area nodes of the target node,the adjacent areas information of nodes in the road network is then aggregated using a graph *** data is output using a fully connected layer at the *** findings show that S-GNN can improve short-and long-term traffic prediction accuracy to a greater extent;in comparison to the control model,the RMSE of S-GNN is reduced by about 0.571 to 9.288 and the MAE(Mean Absolute Error)by about 0.314 to *** experimental results on two real datasets,Pe MSD7(M)and PEMS-BAY,also support this claim.

关键词： Urban traffic traffic temporal correlation GNN prediction

Reactive transport modeling constraints on the complex genesis of a lacustrine dolomite reservoir: A case from the Eocene Qaidam Basin,China

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Petroleum Science 2024年第4期21卷 2240-2256页

作者： Ying Xiong Bo Liu xiu-Cheng Tan zheng-Meng Hou Jia-Shun luo Ya-Chen Xie Kai-Bo Shi Kun-Yu Wu School of Earth and Space Sciences Peking University Institute of Oil and Gas Peking University China National Petroleum Corporation Key Laboratory of Carbonate Reservoirs Southwest Petroleum University Institute of Subsurface Energy Systems Clausthal University of Technology Research Institute of Exploration and Development PetroChina Qinghai Oil Field Company

Reactive transport modeling(RTM) is an emerging method used to address geological issues in diagenesis research. However, the extrapolation of RTM results to practical reservoir prediction is not sufficiently understood. This paper presents a case study of the Eocene Qaidam Basin that combines RTM results with petrological and mineralogical evidence. The results show that the Eocene Xiaganchaigou Formation is characterized by mixed siliciclastic-carbonate-evaporite sedimentation in a semiclosed saline lacustrine environment. Periodic evaporation and salinization processes during the syngeneticpenecontemporaneous stage gave rise to the replacive genesis of dolomites and the cyclic enrichment of dolomite in the middle-upper parts of the meter-scale depositional sequences. The successive change in mineral paragenesis from terrigenous clastics to carbonates to evaporites was reconstructed using RTM simulations. Parametric uncertainty analyses further suggest that the evaporation intensity(brine salinity) and particle size of sediments(reactive surface area) were important rate-determining factors in the dolomitization, as shown by the relatively higher reaction rates under conditions of higher brine salinity and fine-grained sediments. Combining the simulation results with measured mineralogical and reservoir physical property data indicates that the preservation of original intergranular pores and the generation of porosity via replacive dolomitization were the major formation mechanisms of the distinctive lacustrine dolomite reservoirs(widespread submicron intercrystalline micropores) in the Eocene Qaidam Basin. The results confirm that RTM can be effectively used in geological studies, can provide a better general understanding of the dolomitizing fluid-rock interactions, and can shed light on the spatiotemporal evolution of mineralogy and porosity during dolomitization and the formation of lacustrine dolomite reservoirs.

关键词： Reactive transport modeling Lacustrine dolomite Mineralogy and porosity evolution Reservoir genesis

Hypoglycemic effect and the mechanism of action of a polysaccharide from sweet corncob in a high-fat diet and streptozotocin-induced diabetic mice

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Food Science and Human Wellness 2024年第3期13卷 1543-1555页

作者： Xin Wang Weiye xiu Ye Han Zhili Wang Yu luo Yongqiang Ma Heilongjiang Provincial Key Laboratory of Cereals and Comprehensive Processing of Cereal Resources College of Food EngineeringHarbin University of CommerceHarbin 150028China

Type 2 diabetes mellitus(T2DM)is a metabolic disease caused by a glycolipid metabolism disorder and isletβ-cell ***-80-I is a biologically active water-soluble polysaccharide isolated from sweet corncob,an agricultural *** hypoglycemic effects of SCP-80-I on T2DM mice and its mechanisms were investigated in this ***-80-I was found to significantly reduce blood glucose and lipid deposition levels in T2DM mice,as well as decrease serum leptin and increase adiponectin ***,real time-polymerase chain reaction(RT-PCR)and Western blotting results revealed that SCP-80-I could regulate the expression of several glycolipid metabolisms and insulin secretion genes and proteins,including 5'-AMP-activated protein kinase(AMPK),carnitine palmitoyltransferase I(CPTI),and acetyl coenzyme A carboxylase(ACC)in the liver and AMPK,sirtuin1(Sirtl),peroxisome proliferator-activated receptorycoactivator-1(PGC-1α),and uncoupling protein 2(UCP2)in the *** have a hypoglycemic effect,SCP-80-1 regulated glycolipid metabolism and islet cell function in the liver by regulating the AMPK/AC C/CPT1 signaling pathway and the AMPK/Sirt1/PGC-1αand AMPK/Sirtl/UCP2 signaling *** findings improve our understanding of polysaccharides derived from sweet corncob and the use of SCP-80-I in the production of hypoglycemic foods.

关键词： Sweet corn cob polysaccharide Type 2 diabetes Signal pathway 5’-AMP-activated protein kinase(AMPK)