检索结果-南通市图书馆

View of thermodynamic phase transition of the charged Gauss-Bonnet AdS black hole via the shadow

在线全文

学校读者我要写书评

暂无评论

Chinese Physics B 2024年第4期33卷 355-362页

作者：何柯腱郭森罗智李国平 College of Physics Chongqing UniversityChongqing 401331China Guangxi Key Laboratory for Relativistic Astrophysics School of Physical Science and TechnologyGuangxi UniversityNanning 530004China School of Physics and Astronomy China West Normal UniversityNanchong 637000China

We examine thermodynamic phase transition(PT)of the charged Gauss-Bonnet Ad S black hole(BH)by utilizing the shadow *** this system,we rescale the corresponding Gauss-Bonnet coefficientαby a factor of 1/(D-4),and ensure thatαis positive to avoid any singularity *** equation derived for the shadow radius indicates that it increases as the event horizon radius increases,making it an independent variable for determining BH *** investigating the PT curve in relation to shadows,we can observe that the shadow radius can be used as an alternative to the event horizon radius in explaining the phenomenon of BH ***,the results indicate that an increase in the parameterαcorresponds to a decrease in the temperature of the *** utilizing the relationship between the temperature and the shadow radius,it is possible to obtain the thermal profile of the Gauss-Bonnet AdS *** is evident that there is an N-type variation in temperature for pressures Py,as the parameterαincreases,the region covered by shadow expands while the temperature *** utilization of BH shadows as a probe holds immense significance in gaining a deeper understanding of BH thermodynamic behavior.

关键词： Gauss-Bonnet AdS black hole thermodynamic shadow

Transformer-Aided Deep Double Dueling Spatial-Temporal q-Network for Spatial Crowdsourcing Analysis

在线全文

学校读者我要写书评

暂无评论

Computer Modeling in Engineering & Sciences 2024年第4期139卷 893-909页

作者： yu Li Mingxiao Li Dongyang Ou Junjie guo Fangyuan Pan Department of Computing Hangzhou Dianzi UniversityHangzhou310018China

With the rapid development ofmobile Internet,spatial crowdsourcing has becomemore andmore *** crowdsourcing consists of many different types of applications,such as spatial crowd-sensing *** terms of spatial crowd-sensing,it collects and analyzes traffic sensing data from clients like vehicles and traffic lights to construct intelligent traffic prediction *** collecting sensing data,spatial crowdsourcing also includes spatial delivery services like DiDi and *** task assignment and worker selection dominate the service quality for spatial crowdsourcing *** research conducted task assignments via traditional matching approaches or using simple network ***,advanced mining methods are lacking to explore the relationship between workers,task publishers,and the spatio-temporal attributes in ***,in this paper,we propose a Deep Double Dueling Spatial-temporal q Network(D3SqN)to adaptively learn the spatialtemporal relationship between task,task publishers,and workers in a dynamic environment to achieve optimal ***,D3SqNis revised through reinforcement learning by adding a spatial-temporal transformer that can estimate the expected state values and action advantages so as to improve the accuracy of task *** experiments are conducted over real data collected fromDiDi and ELM,and the simulation results verify the effectiveness of our proposed models.

关键词： Historical behavior analysis spatial crowdsourcing deep double dueling q-networks

A Note on the Signless Laplacian Spectral Ordering of Graphs with Given Size

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Mathematical Research with Applications 2024年第3期44卷 304-312页

作者： Nannan LIU Shuguang guo School of Mathematics and Statistics Qinghai Normal University School of Mathematics and Statistics Yancheng Teachers University

Abstract For a simple undirected graph G with fixed size m≥2k （k∈Z+） and maximum degree?（G）≤m-k,we give an upper bound on the signless Laplacian spectral radius q（G）of *** two connected graphs G1and G2with size m≥8,employing this upper bound,we prove that q（G1）>q（G2） if?（G1）>?（G2）+1 and■.For triangle-free graphs,we prove two stronger *** an application,we completely characterize the graph with maximal signless Laplacian spectral radius among all graphs with size m and circumference c for m≥max{2c,c+9},which partially answers the question proposed by Chen et ***[Linear Algebra Appl.,2022,645:123–136].

关键词： signless Laplacian spectral radius upper bound ordering size circumference

Viscoacoustic generalized screen propagator in constant-q model

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Petroleum Science 2024年第4期21卷 2356-2369页

作者： Zhong-Kui Dai Jia-Chun you Xing-guo Huang Wei Liu College of Geophysics Chengdu University of Technology College of Instrumentation and Electrical Engineering Jilin University

When seismic waves propagate through the geological formation, there is a significant loss of energy and a decrease in imaging resolution, because of the viscoacoustic properties of subsurface medium. This profoundly impacts seismic wavefield propagation, imaging and interpretation. To accurately image the true structure of subsurface medium, the consensus among geophysicists is to no longer treat subsurface medium as ideal homogeneous medium, but rather to incorporate the viscoacoustic properties of subsurface medium. Based on the generalized screen propagator using conventional acoustic wave equation(acoustic GSP), our developed method introduces viscoacoustic compensation strategy, and derives a one-way wave generalized screen propagator based on time-fractional viscoacoustic wave equation(viscoacoustic GSP). In numerical experiments, we conducted tests on two-dimensional multi-layer model and the Marmousi model. When comparing with the acoustic GSP using the acoustic data, we found that the imaging results of the viscoacoustic GSP using the viscoacoustic data showed a significant attenuation compensation effect, and achieved imaging results for both algorithms were essentially consistent. However, the imaging results of acoustic GSP using viscoacoustic data showed significant attenuation effects, especially for deep subsurface imaging. This indicates that we have proposed an effective method to compensate the attenuated seismic wavefield. Our application on a set of real seismic data demonstrated that the imaging performance of our proposed method in local areas surpassed that of the conventional acoustic GSP. This suggests that our proposed method holds practical value and can more accurately image real subsurface structures while enhancing imaging resolution compared with the conventional acoustic GSP. Finally, with respect to computational efficiency, we gathered statistics on running time to compare our proposed method with conventional q-RTM, and it is evid

关键词： One-way wave equation Viscoacoustic wave equation Generalized screen propagator Attenuation and dispersion effects

Seasonal variation of mesoscale eddy intensity in the global ocean

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Acta Oceanologica Sinica 2024年第1期43卷 48-58页

作者： yongcan Zu yue Fang Shuangwen Sun Libao Gao yang yang Guijun guo First Institute of Oceanography/Key Laboratory of Marine Science and Numerical Modeling Ministry of Natural ResourcesQingdao 266061China Laboratory for Regional Oceanography and Numerical Modeling Laoshan LaboratoryQingdao 266237China Shandong Key Laboratory of Marine Science and Numerical Modeling Qingdao 266061China

Mesoscale eddies are a prominent oceanic phenomenon that plays an important role in oceanic mass transport and energy *** by rotational speed,the eddy intensity is one of the most fundamental properties of an ***,the seasonal spatiotemporal variation in eddy intensity has not been examined from a global ocean *** this study,we unveil the seasonal spatiotemporal characteristics of eddy intensity in the global ocean by using the latest satellite-altimetry-derived eddy trajectory data *** results suggest that the eddy intensity has a distinct seasonal variation,reaching a peak in spring while attaining a minimum in autumn in the Northern Hemisphere and the opposite in the Southern *** seasonal variation of eddy intensity is more intense in the tropical-subtropical transition zones within latitudinal bands between 15°and 30°in the western Pacific Ocean,the northwestern Atlantic Ocean,and the eastern Indian Ocean because baroclinic instability in these areas changes *** analysis found that the seasonal variation of baroclinic instability precedes the eddy intensity by a phase of 2–3 months due to the initial perturbations needing time to grow into mesoscale eddies.

关键词： seasonal variation mesoscale eddy intensity baroclinic instability global ocean

MADRL-based UAV swarm non-cooperative game under incomplete information

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Aeronautics 2024年第6期37卷 293-306页

作者： Ershen WANG Fan LIU Chen HONG Jing guo Lin ZHAO Jian XUE Ning HE School of Electronic and Information Engineering Shenyang Aerospace UniversityShenyang 110136China College of Robotics Beijing Union UniversityBeijing 100101China School of Engineering Science University of Chinese Academy of SciencesBeijing 100049China College of Smart City Beijing Union UniversityBeijing 100101China

Unmanned Aerial Vehicles(UAVs)play increasing important role in modern *** this paper,considering the incomplete observation information of individual UAV in complex combat environment,we put forward an UAV swarm non-cooperative game model based on Multi-Agent Deep Reinforcement Learning(MADRL),where the state space and action space are constructed to adapt the real features of UAV swarm air-to-air *** multi-agent particle environment is employed to generate an UAV combat scene with continuous observation *** recently popular MADRL methods are compared extensively in the UAV swarm noncooperative game model,the results indicate that the performance of Multi-Agent Soft Actor-Critic(MASAC)is better than that of other MADRL methods by a large *** swarm employing MASAC can learn more effective policies,and obtain much higher hit rate and win *** under different swarm sizes and UAV physical parameters are also performed,which implies that MASAC owns a well generalization ***,the practicability and convergence of MASAC are addressed by investigating the loss value of q-value networks with respect to individual UAV,the results demonstrate that MASAC is of good practicability and the Nash equilibrium of the UAV swarm non-cooperative game under incomplete information can be reached.

关键词： UAV swarm Reinforcement learning Deep learning Multi-agent Non-cooperative game Nash equilibrium

Analysis of Fatty Acid in Biological Samples Using Liquid Chromatography–quadrupole-Orbitrap Mass Spectrometry Under Parallel Reaction Monitoring Mode

在线全文

学校读者我要写书评

暂无评论

Journal of Analysis and Testing 2024年第2期8卷 210-217页

作者： Jingxuan yang Wenjun guo Xiaohang Xu Liang Zhao yajuan Xu yang Wang School of Pharmaceutical Sciences Changchun University of Chinese MedicineChangchun130117China Key Laboratory of Medicinal Materials Jilin Academy of Chinese Medicine SciencesChangchun130021China Jilin Ginseng Academy Changchun University of Chinese MedicineChangchun130117China

Fatty acids(FAs)are an important class of functional small molecules and participate in a variety of life biological *** experiment proposed a liquid chromatography–quadrupole-qrbitrap mass spectrometry(LC–q-Orbitrap MS)method to perform FA profiling under parallel reaction monitoring(PRM)acquisition *** FA was derivatized by 2-dimethylaminoethylamine(DMED)to increase the ionization e fficiency and provide the characterized fragment *** mass spectra obtained from full scan,multiple ion monitoring(MIM),and PRM were *** results showed that the protonated ion of FA+DMED–H2O was detected and the neutral loss of 45.06 Da was observed in the tandem mass *** PRM method provided the highest selectivity and sensitivity for FA detection with the help of accurate mass weight and specific neutral loss-based *** method validation was performed using the FA standards and pooled quality control serum sample,which showed that the established method had good repeatability,stability,and ***,the developed method was successfully applied to analyze the rat serum and brain tissue samples for the drug e ffi-cacy evaluation of gross saponin of Tribulus terrestris ***(GSTTF)against middle cerebral artery occlusion(MCAO)-induced ischemic *** method has extensive practicability and great potential in the detection of FA,especially for the analysis of samples with complex matrices.

关键词： Fatty acid Derivatization LC-q-Orbitrap MS Parallel reaction monitoring Biological sample

在线全文

学校读者我要写书评

暂无评论

青藏高原冰尘微生物对有机质的潜在转化过程

中国科学：地球科学 2024年第6期54卷 2008-2019页

作者：郭泌汐刘勇勤钟旭史权何晨郑强蔡阮鸿青藏高原地球系统与资源环境重点实验室中国科学院青藏高原研究所北京100101 兰州大学泛第三极环境中心兰州730000 Department of Earth Oceanand Atmospheric SciencesUniversity of British ColumbiaVancouverBC V6T 1Z4Canada 中国石油大学重质油国家重点实验室北京102249 厦门大学近海海洋环境科学国家重点实验室厦门361102 厦门大学福建省海洋碳汇重点实验室厦门361005

微生物在冰川碳循环中发挥着重要作用,然而当前缺乏对冰尘微生物参与的溶解性有机质(DOM)转化过程的深入研究.本研究利用了分析化学和微生物生态学的主流手段——超高分辨率的傅里叶变换离子回旋共振质谱(FT-ICR MS)和微生物16S rRNA测... 详细信息

微生物在冰川碳循环中发挥着重要作用,然而当前缺乏对冰尘微生物参与的溶解性有机质(DOM)转化过程的深入研究.本研究利用了分析化学和微生物生态学的主流手段——超高分辨率的傅里叶变换离子回旋共振质谱(FT-ICR MS)和微生物16S rRNA测序技术,分别解析了培养实验中青藏高原龙匣宰陇巴冰川冰尘的DOM分子组成以及微生物群落,并耦联两者构建了复杂微生物参与的冰川DOM转化过程.研究结果表明:在60天的培养实验中,冰尘DOM的生物可利用性随着培养时间的增加而降低,微生物对DOM组分的转化过程可分为三个阶段.在前7天里,微生物选择性降解了具有较高H/Cwa和较低O/Cwa的DOM分子,且群落变化不大;在第15至30天期间,DOM组分保持稳定,但微生物多样性增加;到培养末期, DOM分子在微生物作用下转化为难降解的惰性DOM组分,这些惰性DOM具有更高的芳香指数和O/Cwa、更低的H/Cwa以及含有更多的杂原子.此外,培养实验揭示了冰尘中Cyanobacteria、Bacteroidota、Gammaproteobacteria、Firmicutes和Actinobacteriota等类群协同作用于DOM组分转化,使其变得惰性.本研究揭示了冰尘中微生物转化DOM组分的过程,为理解微生物在冰川有机碳循环中的作用提供了新见解.

关键词：冰尘溶解性有机质微生物降解微生物群落时间变化

On-Chip Micro Temperature Controllers Based on Freestanding Thermoelectric Nano Films for Low-Power Electronics

在线全文

学校读者我要写书评

暂无评论

Nano-Micro Letters 2024年第7期16卷 98-108页

作者： qun Jin Tianxiao guo Nicolas Perez Nianjun yang Xin Jiang Kornelius Nielsch Heiko Reith Institute for Metallic Materials Leibniz Institute for Solid State and Materials Research01069 DresdenGermany Institute of Materials Engineering University of Siegen57076 SiegenGermany Institute of Applied Physics Technical University of Dresden01069 DresdenGermany Institute of Materials Science Technical University of Dresden01069 DresdenGermany

Multidimensional integration and multifunctional com-ponent assembly have been greatly explored in recent years to extend Moore’s Law of modern ***,this inevitably exac-erbates the inhomogeneity of temperature distribution in microsystems,making precise temperature control for electronic components extremely ***,we report an on-chip micro temperature controller including a pair of thermoelectric legs with a total area of 50×50μm^(2),which are fabricated from dense and flat freestanding Bi2Te3-based ther-moelectric nano films deposited on a newly developed nano graphene oxide membrane *** tunable equivalent thermal resistance is controlled by electrical currents to achieve energy-efficient temperature control for low-power electronics.A large cooling temperature difference of 44.5 K at 380 K is achieved with a power consumption of only 445μW,resulting in an ultrahigh temperature control capability over 100 K mW^(-1).Moreover,an ultra-fast cooling rate exceeding 2000 K s^(-1) and excellent reliability of up to 1 million cycles are *** proposed on-chip temperature controller is expected to enable further miniaturization and multifunctional integration on a single chip for microelectronics.

关键词： Temperature control Low-power electronics On-chip micro temperature controller Freestanding thermoelectric nano films Temperature-sensitive components