检索结果-南通市图书馆

Product Form Solution of a Queuing-Inventory System with Lost Sales and Server Vacation

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 Systems Science & Complexity 2024年第2期37卷 729-758页

作者： yue Dequan zhang Yuying XU Xiuli yue Wuyi School of Science Yanshan UniversityQinhuangdao 066004China School of Economics and Management Yanshan UniversityQinhuangdao 066004China The Kyoto College of Graduate Studies for Informatics Kyoto City 606-8225Japan

In this study,the authors consider an M/M/1 queuing system with attached inventory under an(s,S)control *** server takes multiple vacations whenever the inventory is *** is assumed that the lead time and the vacation time follow exponential *** authors formulate the model as a quasi-birth-and-dearth(QBD)process and derive the stability condition of the ***,the stationary distribution in product form for the joint process of the queue length,the inventory level,and the server’s status is ***,the conditional distributions of the inventory level when the server is on and operational,and when it is off due to a vacation,are *** the stationary distribution,the authors obtain some performance measures of the *** authors investigate analytically the effect of the server’s vacation on the performance ***,several numerical examples are presented to investigate the effects of some parameters on the performance measures,the optimal policy,and the optimal cost.

关键词： Cost function multiple vacations product form solution queuing-inventory system (s S)control policy

Compositional evolution for mixed aerosols containing gluconic acid and typical nitrate and the effect of multiply factors on hygroscopicity

在线全文

学校读者我要写书评

暂无评论

Journal of Environmental Sciences 2024年第5期139卷 206-216页

作者： yue Zhu Shufeng Pang Yunhong zhang School of Chemistry and Chemical Engineering Beijing Institute of TechnologyBeijing 100081China

The aging process of atmospheric aerosols usually leads to a mixture of inorganic salts and organic compounds of anthropogenic *** organic compounds,polyhydroxy organic acids are important components,however,the study on composition and hygroscopic properties of the mixture containing inorganics and polyhydroxy organic acids is *** this study,gluconic acid,the proxy of polyhydroxy organic acids,is mixed with the representative nitrate(Mg(NO_(3.)_(2),Ca(NO_(3.)_(2))to form ***-FTIR and optical microscopy are employed to study the component changes and hygroscopicity as a function of relative *** relative humidity fluctuates,the FTIR-ATR spectra display that the internal mixed gluconic acid(CH_(2)(CH)_(4)(OH)_(5)COOH)and nitrate can react to release acidic gases,forming relevant gluconate and further affecting the *** specific presentation is particles cannot be recovered to their original size after the dehydration-hydration process and there will be some disparities in GF for mixed *** the gluconic acid-Ca(NO_(3.)_(2)/Mg(NO_(3.)_(2)mixtures with molar ratios of 1:1,higher degree of reaction resulting in the production of large amounts of gluconate should be responsible to the lower hygroscopicity compared to ZSR *** 1:2 gluconic acid-nitrate mixed systems(with higher nitrate content),the hygroscopicity of mixtures are higher than the ZSR prediction.A possible reason could be‘salt-promoting effect’on the organic fractions of the surplus inorganic salt in the *** data can improve the chemical composition list evaluation,in turn hygroscopic properties and phase state of atmospheric aerosol,and then the climate effect.

关键词： Hygroscopicity Gluconic acid Reaction ZSR simulation Size growth factors

Solar evaporation for simultaneous oil-water separation and electricity generation with Janus wood-based absorbers

在线全文

学校读者我要写书评

暂无评论

Frontiers of Environmental Science & Engineering 2024年第2期18卷 13-23页

作者： yue Yang Ze Fu Qi zhang Jiangsu Key Laboratory of Chemical Pollution Control and Resources Reuse School of Environmental and Biological EngineeringNanjing University of Science&TechnologyNanjing 210094China Key Laboratory of Industrial Ecology and Environmental Engineering(Ministry of Education) School of Environmental Science and TechnologyDalian University of TechnologyDalian 116024China National Laboratory of Solid State Microstructures Collaborative Innovation Center of Advanced MicrostructuresCollege of Engineering and Applied SciencesKey Laboratory of Intelligent Optical Sensing and Manipulation(Ministry of Education)Jiangsu Key Laboratory of Artificial Functional MaterialsNanjing UniversityNanjing 210093China

Oily wastewater from ocean oil spills endangers marine ecosystems and human health. Therefore, developing an effective and sustainable solution for separating oil-water mixtures is urgent. Interfacial solar photothermal evaporation is a promising approach for the complete separation of two-phase mixtures using only solar energy. Herein, we report a carbonized wood-based absorber with Janus structure of comprising a hydrophobic top-layer and an oleophobic bottom-layer for simultaneous solar-driven oil-water separation and electricity generation. Under sunlight irradiation, the rapid evaporation of seawater will induce a separation of oil-water mixtures, and cause a high salt concentration region underlying the interface, while the bottom “bulk water” maintains in a low salt concentration, thus forming a salinity gradient. Electricity can be generated by salinity gradient power. Therefore, oil-water separation efficiency of > 99% and derived extra electricity power of ~0.1 W/m2 is achieved under solar radiation, demonstrating the feasibility of oil-water separation and electricity production synchronously directly using solar energy. This work provides a green and cost-effective path for the separation of oil-water mixtures.

关键词： Oily wastewater Carbonized wood Salinity gradient Electricity generation Solar irradiation

Decadal Changes in Dry and Wet Heatwaves in Eastern China:Spatial Patterns and Risk Assessment

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Advances in Atmospheric Sciences 2024年第10期41卷 2011-2026页

作者： yue zhang Wen ZHOU Ruhua zhang Department of Atmospheric and Oceanic Sciences and Institute of Atmospheric Sciences Fudan UniversityShanghai 200438China CMA-FDU Joint Laboratory of Marine Meteorology Fudan UniversityShanghai 200438China Key Laboratory of Polar Atmosphere-ocean-ice System for Weather and Climate Ministry of EducationFudan UniversityShanghai 200438China

Under global warming,understanding the long-term variation in different types of heatwaves is vital for China’s preparedness against escalating heat *** study investigates dry and wet heatwave shifts in eastern China over recent *** trend analysis displays pronounced warming in inland midlatitudes and the Yangtze River Valley,with increased humidity in coastal *** results indicate intensifying dry heatwaves in northern China,while the Yangtze River Valley sees more frequent dry *** the other hand,Indochina and regions north of 25°N also experience intensified wet heatwaves,corresponding to regional humidity *** analysis is conducted based on different situations:strong,frequent dry or wet *** dry heatwaves are influenced by anticyclonic circulations over northern China,accompanied by warming SST anomalies around the coastal midlatitudes of the western North Pacific(WNP).Frequent dry heatwaves are related to strong subsidence along with a strengthened subtropical high over the *** and frequent wet heatwaves show an intensified Okhotsk high at higher latitudes in the lower troposphere,and a negative circumglobal teleconnection wave train pattern in the upper *** El Niño SST patterns are observed in two kinds of wet heatwave and frequent dry heatwave *** analysis indicates that El Niño events heighten the likelihood of these heatwaves in regions most at *** global warming continues,adapting and implementing mitigation strategies toward extreme heatwaves becomes crucial,especially for the aforementioned regions under significant heat stress.

关键词： decadal changes dry heatwave wet heatwave eastern China

EPR-Net: constructing a non-equilibrium potential landscape via a variational force projection formulation

在线全文

学校读者我要写书评

暂无评论

National Science Review 2024年第7期11卷 135-147页

作者： yue Zhao Wei zhang Tiejun Li Center for Data Science Peking University Zuse Institute Berlin Department of Mathematics and Computer Science Freie Universit?t Berlin Laboratory of Mathematics and Applied Mathematics(LMAM)and School of Mathematical Sciences Peking University Center for Machine Learning Research Peking University

We present EPR-Net, a novel and effective deep learning approach that tackles a crucial challenge in biophysics: constructing potential landscapes for high-dimensional non-equilibrium steady-state ***-Net leverages a nice mathematical fact that the desired negative potential gradient is simply the orthogonal projection of the driving force of the underlying dynamics in a weighted inner-product ***, our loss function has an intimate connection with the steady entropy production rate(EPR),enabling simultaneous landscape construction and EPR estimation. We introduce an enhanced learning strategy for systems with small noise, and extend our framework to include dimensionality reduction and the state-dependent diffusion coefficient case in a unified fashion. Comparative evaluations on benchmark problems demonstrate the superior accuracy, effectiveness and robustness of EPR-Net compared to existing methods. We apply our approach to challenging biophysical problems, such as an eight-dimensional(8D)limit cycle and a 52D multi-stability problem, which provide accurate solutions and interesting insights on constructed landscapes. With its versatility and power, EPR-Net offers a promising solution for diverse landscape construction problems in biophysics.

关键词： high-dimensional potential landscape non-equilibrium system entropy production rate dimensionality reduction deep learning

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

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

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

A novel three-inflection-point sliding mode control framework for forward-tilting morphing aerospace vehicle with performance constraints and actuator faults

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Aeronautics 2024年第8期37卷 293-310页

作者： Xinkai LI Lei DOU Hongli zhang yue MENG School of Electrical Engineering Xinjiang UniversityUrumqi 830047China

A prescribed performance control scheme based on the three-inflection-point hyperbolic function and predefined time performance function is proposed to solve the trajectory tracking problem of the forward-tilting morphing aerospace vehicle with time-varying actuator *** accurately estimate the loss degree of actuator faults,an immersion and invariance observer based on the predefined time dynamic scale factor is designed to estimate and compensate it.A composite dynamic sliding mode surface is designed using a three-inflection-point hyperbolic function,and a novel three-inflection-point sliding mode control framework is *** convergent domain of the sliding manifold is adjusted by parameters,and the system error convergence is controllable.A transfer function is designed to eliminate the sensitivity of the three-inflection-point hyperbolic sliding mode to the unknown initial state,and combined with the barrier Lyapunov function,and the performance constraint of the system is *** global asymptotic stability of the system is demonstrated using a strict mathematical *** effectiveness and superiority of the proposed control scheme are proven by simulation experiments.

关键词： Morphing aerospace vehicle Actuator faults Immersion and invariance Three-inflection-point sliding mode control Prescribed performance control

Domain Engineering the Flexoelectric Response of BaTiO_(3.–SrTiO_(3. Binary Films:A Phase Field Study

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Acta Mechanica Solida Sinica 2024年第4期37卷 590-597页

作者： Junyu Tao Fan zhang Jianyuan zhang Weijin Chen yue Zheng School of Materials Shenzhen Campus of Sun Yat-sen UniversityShenzhen518107China Guangdong Provincial Key Laboratory of Magnetoelectric Physics and Devices School of PhysicsSun Yat-sen UniversityGuangzhou510275China State Key Laboratory of Optoelectronic Materials and Technologies School of PhysicsSun Yat-sen UniversityGuangzhou510275China Centre for Physical Mechanics and Biophysics School of PhysicsSun Yat-sen UniversityGuangzhou510275China Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai) Zhuhai519082China

The flexoelectric effect describes the interplay between material polarization and strain *** much research has focused on control strategies for flexoelectricity,the impact of ferroelectric domain structure on the flexoelectric effect remains *** phase field simulations,we conduct a comparative study on the flexoelectric response of two types of BaTiO_(3.–SrTiO_(3. binary films:BaTiO_(3.–SrTiO_(3. multilayers and(Ba,Sr)TiO_(3. solid *** findings reveal that the flexoelectric response of these two systems,at the same Ba/Sr ratio,differs not only in magnitude but also in other aspects like temperature dependence,linearity,and hysteresis,due to their different ferroelectric domain structures and evolution *** study deepens our current understanding of flexoelectricity in ferroelectrics and suggests“domain engineering”as a potential way to tailor this effect.

关键词： Ferroelectric Flexoelectricity Multilayers Solid solution Phase field

Interface structure of α-Mg/14H-LPSO:First-principles prediction and experimental study

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 Rare Earths 2024年第9期42卷 1792-1799,I0006页

作者： Yuan Shi Xiaohua zhang Hongyan yue Chao Li School of Materials Science and Chemical Engineering Harbin University of Science and TechnologyHarbin150040China

The interfacial structure of the α-Mg/14H-LPSO phase in rare earth-including magnesium alloy was investigated via high-angle annular dark-field scanning transmission electron microscopy(HAADFSTEM) imaging and first-principles calculations of density-functional *** possible interfacial models were constructed according to the different terminations of the LPSO phase,and the corresponding interfacial energies were calculated,from which the four most stable structures(Terl-MgY-hollow,Ter2-Zn-hollow,Ter3.MgYII-hollow and Ter4-Mg-bridge) were *** interfacial phase diagrams related to the Y chemical potentials were obtained from the calculations,and the most stable interfacial structure was ***-MgY-hollow and Ter2-Zn-hollow have the lowest interfacial energies in the range of-0.7 eV <Δμγ<-0.6 eV,where fluctuating change of state is the minimized and the interface is the most *** separation work of the two models was calculated to predict the bonding strength of the structures at both ends of the *** calculation results show that the maximum interfacial separation work is 1.45 J/m^(2) for the interface model of α-Mg and 14H-LPSO phase structure with Ter2-Zn-hollow termination.

关键词： Rare earths Magnesium alloy HAADF-STEM LPSO First-principles Interface