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THE SPIRIT OF CAPITALISM,NON-EXPECTEDUTILITY AND ASSET PRICING 被引量:3
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作者 Yang Yunhong 《Acta Mathematica Scientia》 SCIE CSCD 1999年第4期409-416,共8页
This paper investigates testable restrictions on the time-series behavior of consumption and asset returns implied by a representative agent model with the spirit of capitalism in which intertemporal preference is rep... This paper investigates testable restrictions on the time-series behavior of consumption and asset returns implied by a representative agent model with the spirit of capitalism in which intertemporal preference is represented by a utility function that generalizes conventional,time-additive,expected utility.In the recursive structure of preference,the author examines the implication for cosumptions,portfolio holdings,and stock-market prices when investors accumulate wealth not only for the sake of consumption but also for wealth-induced social status.When investors care about relative social status,the propensity to consume and risk-taking behavior will depend on social standards,and stock prices will be volatible.Hence,the spirit of capitalism seems to be a driving force behind stock-market volatility and economic growth.Because the elasticity df substitution and the coefficient of relative risk aversion are independent and the spirit of capitalism is introduced,the equity premium puzzle can be partially explained in the model. 展开更多
关键词 the spirit of capitalism non-expected utility asset pricing wealth growth
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BIM-Based Visualization System for Settlement Warning in Multi-Purpose Utility Tunnels(MUTs)
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作者 Ping Wu Jie Zou +1 位作者 Wangxin Li Yidong Xu 《Structural Durability & Health Monitoring》 2026年第1期283-301,共19页
The existing 2D settlement monitoring systems for utility tunnels are heavily reliant on manual interpretation of deformation data and empirical predictionmodels.Consequently,early anomalies(e.g.,minor cracks)are ofte... The existing 2D settlement monitoring systems for utility tunnels are heavily reliant on manual interpretation of deformation data and empirical predictionmodels.Consequently,early anomalies(e.g.,minor cracks)are often misjudged,and warnings lag by about 24 h without automated spatial localization.This study establishes a technical framework for requirements analysis,architectural design,and data-integration protocols.Revit parametric modelling is used to build a 3D tunnel model with structural elements,pipelines and 18 monitoring points(for displacement and joint width).Custom Revit API code integrated real-time sensor data into the BIM platform via an automated pipeline.The system achieved a spatial accuracy of±1 mm in locating deformation hotspots.Notifications are triggered within 10 s of anomaly detection,and the system renders 3D risk propagation paths in real-time.Realtime 3D visualization of risk propagation paths is also facilitated.The efficacy of the solution was validated in a Ningbo utility tunnel project,where it was demonstrated that it eliminates human-dependent judgment errors and reduces warning latency by 99.9%compared to conventional methods.The BIM-IoT integrated approach,which enables millimetre-level precision in risk identification and near-instantaneous response,establishes a new paradigm for intelligent infrastructure safety management. 展开更多
关键词 Multi-purpose utility tunnels settlement monitoring BIM-based visualization WARNING
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Utility and influence mechanism of densification modulation on grain boundary diffusion in NdFeB magnets 被引量:1
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作者 San'gen Luo Munan Yang +4 位作者 Shuwei Zhong Sajjad Ur Rehman Jiajie Li Xiaoqiang Yu Bin Yang 《Journal of Rare Earths》 2025年第3期569-577,I0006,共10页
Grain boundary diffusion technology is pivotal in the preparation of high-performance NdFeB magnets.This study investigates the factors that affect the efficiency of grain boundary diffusion,starting from the properti... Grain boundary diffusion technology is pivotal in the preparation of high-performance NdFeB magnets.This study investigates the factors that affect the efficiency of grain boundary diffusion,starting from the properties of the diffusion matrix.Through the adjustment of the sintering process,we effectively prepared magnets with varied densities that serve as the matrix for grain boundary diffusion with TbH,diffusion.The mobility characteristics of the Nd-rich phase during the densification stage are leveraged to ensure a more extensive distribution of heavy rare earth elements within the magnets.According to the experimental results,the increase in coercivity of low-density magnets after diffusion is significantly greater than that of relatively high-density magnets.The coercivity values measured are 805.32 kA/m for low-density magnets and 470.3 kA/m for high-density magnets.Additionally,grain boundary diffusion notably enhances the density of initial low-density magnets,addressing the issue of low density during the sintering stage.Before the diffusion treatment,the Nd-rich phases primarily concentrate at the triangular grain boundaries,resulting in an increased number of cavity defects in the magnets.These cavity defects contain atoms in a higher energy state,making them more prone to transition.Consequently,the diffusion activation energy at the void defects is lower than the intracrystalline diffusion activation energy,accelerating atom diffusion.The presence of larger cavities also provides more space for atom migration,thereby promoting the diffusion process.After the diffusion treatment,the proportion of bulk Nd-rich phases significantly decreases,and they infiltrate between the grains to fill the cavity defects,forming continuous fine grain boundaries.Based on these observations,the study aims to explore how to utilize this information to develop an efficient technique for grain boundary diffusion. 展开更多
关键词 NdFeB magnets DENSITY Grain boundary diffusion Defect utility Rare earths
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Empowering Underground Utility Tunnel Operation and Maintenance with Data Intelligence:Risk Factors,Prospects,and Challenges 被引量:1
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作者 Jie Zou Ping Wu +2 位作者 Jianwei Chen Weijie Fan Yidong Xu 《Structural Durability & Health Monitoring》 2025年第3期441-471,共31页
As an essential part of the urban infrastructure,underground utility tunnels have a long service life,complex structural performance evolution and dynamic changes both inside and outside the tunnel.These combined fact... As an essential part of the urban infrastructure,underground utility tunnels have a long service life,complex structural performance evolution and dynamic changes both inside and outside the tunnel.These combined factors result in a wide variety of disaster risks during the operation and maintenance phase,which make risk management and control particularly challenging.This work first reviews three common representative disaster factors during the operation and maintenance period:settlement,earthquakes,and explosions.It summarizes the causes of disasters,key technologies,and research methods.Then,it delves into the research on the intelligent operation and maintenance architecture for utility tunnels.Additionally,it explores the data challenges,monitoring technologies,and management platform architectures faced during the operation and maintenance process.This work provides new research perspectives for the long-term,healthy,and sustainable development of utility tunnels,which serve as the underground arteries of cities. 展开更多
关键词 Integrated utility tunnels operational hazards critical technologies intelligent maintenance smart platforms
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Utility-Driven Edge Caching Optimization with Deep Reinforcement Learning under Uncertain Content Popularity
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作者 Mingoo Kwon Kyeongmin Kim Minseok Song 《Computers, Materials & Continua》 2025年第10期519-537,共19页
Efficient edge caching is essential for maximizing utility in video streaming systems,especially under constraints such as limited storage capacity and dynamically fluctuating content popularity.Utility,defined as the... Efficient edge caching is essential for maximizing utility in video streaming systems,especially under constraints such as limited storage capacity and dynamically fluctuating content popularity.Utility,defined as the benefit obtained per unit of cache bandwidth usage,degrades when static or greedy caching strategies fail to adapt to changing demand patterns.To address this,we propose a deep reinforcement learning(DRL)-based caching framework built upon the proximal policy optimization(PPO)algorithm.Our approach formulates edge caching as a sequential decision-making problem and introduces a reward model that balances cache hit performance and utility by prioritizing high-demand,high-quality content while penalizing degraded quality delivery.We construct a realistic synthetic dataset that captures both temporal variations and shifting content popularity to validate our model.Experimental results demonstrate that our proposed method improves utility by up to 135.9%and achieves an average improvement of 22.6%compared to traditional greedy algorithms and long short-term memory(LSTM)-based prediction models.Moreover,our method consistently performs well across a variety of utility functions,workload distributions,and storage limitations,underscoring its adaptability and robustness in dynamic video caching environments. 展开更多
关键词 Edge caching video-on-demand reinforcement learning utility optimization
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Personalized fund recommendation with dynamic utility learning
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作者 Jiaxin Wei Jia Liu 《Financial Innovation》 2025年第1期1558-1584,共27页
This study introduces a fund recommendation system based on the ε-greedy algorithm and an incremental learning framework.This model simulates the interaction process when customers browse the web-pages of fund produc... This study introduces a fund recommendation system based on the ε-greedy algorithm and an incremental learning framework.This model simulates the interaction process when customers browse the web-pages of fund products.Customers click on their preferred fund products when visiting a fund recommendation web-page.The system collects customer click sequences to continually estimate and update their utility function.The system generates product lists using the ε-greedy algorithm,where each product on the list has the probability of 1-ε of being selected as an exploitation strategy,and the probability of ε is chosen as the exploration strategy.We perform a series of numerical tests to evaluate the estimation performance with different values of ε. 展开更多
关键词 Personalized fund recommendation ε-greedy algorithm Dynamic utility learning
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Recent advances in carbon-based materials for CO_(2) capture and utilization
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作者 FU Lang YAO Dingding +2 位作者 HU Qiang YAN Shuiping YANG Haiping 《燃料化学学报(中英文)》 北大核心 2026年第3期15-32,共18页
CO_(2) capture and utilization(CCU)technologies have been recognized as crucial strategies for mitigating global warming,reducing carbon emission,and promoting resource circularity.As such,the design and development o... CO_(2) capture and utilization(CCU)technologies have been recognized as crucial strategies for mitigating global warming,reducing carbon emission,and promoting resource circularity.As such,the design and development of related materials have attracted considerable research attention.Carbon-based materials,characterized by tunable pore structures,abundant active sites,high specific surface area,and excellent chemical stability,demonstrate significant potential for applications in CO_(2) capture and utilization.This review systematically analyzes the adsorption behaviors and performance variations of typical carbon materials,including activated carbon,porous carbon,graphene,and carbon nanotubes during CO_(2) capture processes.Concerning CO_(2) utilization,emphasis is placed on recent advances in the catalytic applications of carbon-based materials in key reactions such as methanation,reverse water-gas shift,dry reforming of methane,and alcohol synthesis.Moreover,the benefits and drawbacks of carbon materials in terms of CO_(2) adsorption capacity,catalytic activity,and stability are thoroughly evaluated,and their potential applications in integrated CO_(2) capture and utilization technologies are discussed.Finally,key strategies for enhancing the performance of carbonaceous materials through structural modulation and surface modification are elucidated.This review aims to provide theoretical guidance for the future development and large-scale implementation of carbon-based materials in CCU technologies. 展开更多
关键词 CO_(2)capture and utilization carbon materials ADSORPTION CATALYSIS
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Patterns of utilization of antipsychotic drugs and direct medical costs among patients with schizophrenia in a tertiary care hospital
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作者 Aqeel Haider Lekha Saha Debashish Basu 《World Journal of Psychiatry》 2026年第1期125-135,共11页
BACKGROUND Drug utilization research has an important role in assisting the healthcare administration to know,compute,and refine the prescription whose principal objective is to enable the rational use of drugs.Resear... BACKGROUND Drug utilization research has an important role in assisting the healthcare administration to know,compute,and refine the prescription whose principal objective is to enable the rational use of drugs.Research in developing nations relating to the cost of treatment is scarce when compared with developed countries.Thus,the drug utilization research studies from developing nations are most needed,and their number has been growing.AIM To evaluate patterns of utilization of antipsychotic drugs and direct medical cost analysis in patients newly diagnosed with schizophrenia.METHODS The present study was observational in type and based on a retrospective cohort to evaluate patterns of utilization of antipsychotic drugs using World Health Organization(WHO)core prescribing indicators and anatomical therapeutic chemical/defined daily dose indicators.We also calculated direct medical costs for a period of 6 months.RESULTS This study has found that atypical antipsychotics are the mainstay of treatment for schizophrenia in every age group and subcategories of schizophrenia.The evaluation based on WHO prescribing indicators showed a low average number of drugs per prescription and low prescribing frequency of antipsychotics from the National List of Essential Medicines 2015 and the WHO Essential Medicines List 2019.The total mean drug cost of our study was 1396 Indian rupees.The total mean cost due to the investigation in our study was 1017.34 Indian rupees.Therefore,the total mean direct medical cost incurred on patients in our study was 4337.28 Indian rupees.CONCLUSION The information from the present study can be used for reviewing and updating treatment policy at the institutional level. 展开更多
关键词 Patterns of utilization Antipsychotic drugs Direct medical cost SCHIZOPHRENIA DRUGS
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Research on the Independent Status of the Data Utilization Right
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作者 Zhang Ying 《Contemporary Social Sciences》 2026年第1期140-155,共16页
Among the “three data rights,” the data utilization right has been persistently overlooked, and is similar to a neglected “middle child” in the context of the data rights family. However, it is precisely during th... Among the “three data rights,” the data utilization right has been persistently overlooked, and is similar to a neglected “middle child” in the context of the data rights family. However, it is precisely during the stages of processing and utilization that data undergoes its transformations and where its economic value is ultimately created. A series of recent policy documents on treating data as a factor of production have emphasized that the building of a scientific data property rights system requires a fair and efficient mechanism for benefit distribution, which provides reasonable preference for creators of data value and use value in terms of the income generated by data elements. Constrained by the inertial thinking of property right logic, the data utilization right is often regarded as a “transitional fulcrum” wherein the holders of data resources have to authorize the operators of data products to realize data value thereby. In the future structural design and implementation of the coordination mechanism for the property right system against the backdrop of the data factor-oriented reform, the establishment of data processing and utilization as an independent right will require the implementation of two core initiatives: first, attaching importance to the independent protection of the benefit distribution;second, implementing risk regulation for data security through optimization of governance. These two initiatives will serve as the key for optimizing the data factor governance system and accelerating the release of data value. 展开更多
关键词 utilization right data property rights structure benefit distribution risk regulation
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CO_(2)utilization and fixation in biomass-derived furanics conversion:Thermochemical and electrochemical pathways
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作者 Saeideh Gharouni Fattah Sabah Karimi +5 位作者 Shaoyu Yuan Zheng Li Mohammad Jalal Zohuriaan-Mehr Lu Lin Xianhai Zeng Buxing Han 《Green Energy & Environment》 2026年第1期1-22,共22页
Carbon dioxide(CO_(2))is the main greenhouse gas(GHG)released by human activities.The substitution of fossil resources by biomass as a bio-renewable resource,has significant potential to reduce GHG emissions.The appro... Carbon dioxide(CO_(2))is the main greenhouse gas(GHG)released by human activities.The substitution of fossil resources by biomass as a bio-renewable resource,has significant potential to reduce GHG emissions.The approach to biomass,as the only true full-scale alternative to fossil resources,is progressing rapidly.Converting biomass into furanic compounds,as versatile platform chemicals for synthesizing a wide range of bio-based products is the cornerstone of sustainable technologies.The extensive body of this review combines the biomass valorization to furanic compounds by CO_(2)utilization and furanic compounds conversion by CO_(2)fixation.These processes can be strategically applied through both‘thermochemical’and‘electrochemical’pathways,by utilizing CO_(2)from the atmosphere or industrial emission point and returning it to the natural carbon cycle.In the thermochemical pathway CO_(2)acts as a carbon source(carboxylation and polymerization)or active reaction assistant in the biomass conversion(CO_(2)-assisted conversion),without altering its oxidation state,facilitating the synthesis of valuable products and polymers.Conversely,in the electrochemical pathway,CO_(2)can be used as a carbon source(electrocarboxylation)to give the corresponding carboxylic acid,or it can undergo reduction,yielding methanol,carbon monoxide(CO),formic acid,and analogous compounds,while on the other side,furanic compounds undergo oxidation yielding high-value-added chemicals.Finally,potential future research directions are suggested to promote CO_(2)utilization and fixation in the valorization of biomass-derived furanic compounds,and challenges facing further research are highlighted. 展开更多
关键词 CO_(2)utilization and fixation Biomass valorization Furanic compounds Thermochemical and electrochemical pathways Renewable and sustainable resources
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Analyzing our educational resource deployment of compulsory education by marginal utility
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作者 高丽 程宝良 《陕西师范大学学报(哲学社会科学版)》 CSSCI 北大核心 2006年第S1期353-356,共4页
In the base of utility and marginal utility,the article put forwardthe concept of utility and marginal utilityof educational outlay and the theory of them,and analyzed the actuality of educational resource deployment ... In the base of utility and marginal utility,the article put forwardthe concept of utility and marginal utilityof educational outlay and the theory of them,and analyzed the actuality of educational resource deployment in ourcountry,gave some advice about howtoi mprove our educational resource deployment of compulsory education. 展开更多
关键词 marginal utility educational resource compulsory education
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Neural network approach to predicting mercury emission from utility boiler
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作者 杨宏旻 周波 《Journal of Southeast University(English Edition)》 EI CAS 2008年第1期55-58,共4页
The feasibility of using an ANN method to predict the mercury emission and speciation in the flue gas of a power station under un-tested combustion/operational conditions is evaluated. Based on existing field testing ... The feasibility of using an ANN method to predict the mercury emission and speciation in the flue gas of a power station under un-tested combustion/operational conditions is evaluated. Based on existing field testing datasets for the emissions of three utility boilers, a 3-layer back-propagation network is applied to predict the mercury speciation at the stack. The whole prediction procedure includes: collection of data, structuring an artificial neural network (ANN) model, training process and error evaluation. A total of 59 parameters of coal and ash analyses and power plant operating conditions are treated as input variables, and the actual mercury emissions and their speciation data are used to supervise the training process and verify the performance of prediction modeling. The precision of model prediction ( root- mean-square error is 0. 8 μg/Nm3 for elemental mercury and 0. 9 μg/Nm3 for total mercury) is acceptable since the spikes of semi- mercury continuous emission monitor (SCEM) with wet conversion modules are taken into consideration. 展开更多
关键词 mercury speciations electric utility boiler PREDICTION artificial neural network
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EOS Utility软件在摄影理论可视化教学中的应用
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作者 张廷琦 《电脑知识与技术》 2023年第13期171-173,共3页
可视化的理论知识更容易被识记、理解,而在摄影理论教学中,运用静态的图形图像,并不能理想地将复杂理论知识及其相互间的关系表征、可视化。运用EOS Utility软件进行摄影理论知识的辅助教学,可将各知识点内涵及其相互间的关系进行动态... 可视化的理论知识更容易被识记、理解,而在摄影理论教学中,运用静态的图形图像,并不能理想地将复杂理论知识及其相互间的关系表征、可视化。运用EOS Utility软件进行摄影理论知识的辅助教学,可将各知识点内涵及其相互间的关系进行动态地表征,实现摄影参数可视化、摄影过程可视化、摄影效果可视化,使摄影知识点及其相互间的关系更容易被识记、理解,提高教学效率。 展开更多
关键词 可视化 摄影 知识 教学 EOS utility软件
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Optimal consumption-leisure, portfolio and retirement selection based on α-maxmin expected CES utility with ambiguity 被引量:23
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作者 FEI Wei-yin 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2012年第4期435-454,共20页
This article studies optimal consumption-leisure, portfolio and retirement selection of an infinitely lived investor whose preference is formulated by a-maxmin expected CES utility which is to differentiate ambiguity ... This article studies optimal consumption-leisure, portfolio and retirement selection of an infinitely lived investor whose preference is formulated by a-maxmin expected CES utility which is to differentiate ambiguity and ambiguity attitude. Adopting the recursive multiple- priors utility and the technique of backward stochastic differential equations (BSDEs), we transform the (^-maxmin expected CES utility into a classical expected CES utility under a new probability measure related to the degree of an investor's uncertainty. Our model investi- gates the optimal consumption-leisure-work selection, the optimal portfolio selection, and the optimal stopping problem. In this model, the investor is able to adjust her supply of labor flex- ibly above a certain minimum work-hour along with a retirement option. The problem can be analytically solved by using a variational inequality. And the optimal retirement time is given as the first time when her wealth exceeds a certain critical level. The optimal consumption-leisure and portfolio strategies before and after retirement are provided in closed forms. Finally, the distinctions of optimal consumption-leisure, portfolio and critical wealth level under ambiguity from those with no vagueness are discussed. 展开更多
关键词 α-maxmin expected CES utility stochastic control BSDEs optimization of utility variationalinequality optimal consumption-leisure-portfolio and retirement.
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Seismic response of underground utility tunnels: shaking table testing and FEM analysis 被引量:39
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作者 Jiang Luzhen Chen Jun Li Jie 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2010年第4期555-567,共13页
Underground utility tunnels are widely used in urban areas throughout the world for lifeline networks due to their easy maintenance and environmental protection capabilities. However, knowledge about their seismic per... Underground utility tunnels are widely used in urban areas throughout the world for lifeline networks due to their easy maintenance and environmental protection capabilities. However, knowledge about their seismic performance is still quite limited and seismic design procedures are not included in current design codes. This paper describes a series of shaking table tests the authors performed on a scaled utility tunnel model to explore its performance under earthquake excitation. Details of the experimental setup are first presented focusing on aspects such as the design of the soil container, scaled structural model, sensor array arrangement and test procedure. The main observations from the test program, including structural response, soil response, soil-structure interaction and earth pressure, are summarized and discussed. Further, a finite element model (FEM) of the test utility tunnel is established where the nonlinear soil properties are modeled by the Drucker- Prager constitutive model; the master-slave surface mechanism is employed to simulate the soil-structure dynamic interaction; and the confining effect of the laminar shear box to soil is considered by proper boundary modeling. The results from the numerical model are compared with experiment measurements in terms of displacement, acceleration and amplification factor of the structural model and the soil. The comparison shows that the numerical results match the experimental measurements quite well. The validated numerical model can be adopted for further analysis. 展开更多
关键词 lifeline system utility tunnel shaking table test finite element method soil-structure interaction
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Dynamic response of utility tunnel during the passage of Rayleigh waves 被引量:12
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作者 Jie Li Qingxia Yue Jun Chen 《Earthquake Science》 CSCD 2010年第1期13-24,共12页
The modeling methodologies and calculation of dynamic response of underground structure under Rayleigh waves is investigated in this paper. First the free field responses under Rayleigh waves are analyzed and the nume... The modeling methodologies and calculation of dynamic response of underground structure under Rayleigh waves is investigated in this paper. First the free field responses under Rayleigh waves are analyzed and the numerical results agree well with the theoretical results. Then, the approximate Rayleigh waves are put forward based on the preliminary re- search, and Rayleigh wave field is obtained through fast Fourier transform technique. Taking a utility tunnel as an example, its dynamic responses under Rayleigh waves is calculated by ABAQUS. The results demonstrate that bending deformation is the main component of structural deformation and the deformation at the top of the structure is about twice as much as that at bottom of the structure. The effect of soil-structure interface and the buried depth of underground structure are also investi- gated via parameter analysis. For the shallow buffed underground structures, Rayleigh waves can be the key factor to control the responses and damage of the structure. 展开更多
关键词 utility tunnel Rayleigh wave dynamic response fast Fourier transform
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Cooperative adaptive bidirectional control of a train platoon for efficient utility and string stability 被引量:8
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作者 高士根 董海荣 +3 位作者 宁滨 Roberts Clive 陈磊 孙绪彬 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第9期161-170,共10页
This paper proposes cooperative adaptive control schemes for a train platoon to improve efficient utility and guarantee string stability. The control schemes are developed based on a bidirectional strategy, i.e., the ... This paper proposes cooperative adaptive control schemes for a train platoon to improve efficient utility and guarantee string stability. The control schemes are developed based on a bidirectional strategy, i.e., the information of proximal(preceding and following) trains is used in the controller design. Based on available proximal information(prox-info) of location, speed, and acceleration, a direct adaptive control is designed to maintain the tracking interval at the minimum safe distance. Based on available prox-info of location, an observer-based adaptive control is designed to achieve the same target, which alleviates the requirements of equipped sensors to measure prox-info of speed and acceleration. The developed schemes are capable of on-line estimating of the unknown system parameters and stabilizing the closed-loop system, the string stability of train platoon is guaranteed on the basis of Lyapunov stability theorem. Numerical simulation results are presented to verify the effectiveness of the proposed control laws. 展开更多
关键词 train platoon string stability cooperative adaptive control efficient utility
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UMR: A utility-maximizing routing algorithm for delay-sensitive service in LEO satellite networks 被引量:5
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作者 Lu Yong Zhang Jun Zhang Tao 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2015年第2期499-507,共9页
This paper develops a routing algorithm for delay-sensitive packet transmission in a low earth orbit multi-hop satellite network consists of micro-satellites. The micro-satellite low earth orbit (MS-LEO) network end... This paper develops a routing algorithm for delay-sensitive packet transmission in a low earth orbit multi-hop satellite network consists of micro-satellites. The micro-satellite low earth orbit (MS-LEO) network endures unstable link connection and frequent link congestion due to the uneven user distribution and the link capacity variations. The proposed routing algorithm, referred to as the utility maximizing routing (UMR) algorithm, improve the network utility of the MS-LEO network for carrying flows with strict end-to-end delay bound requirement. In UMR, first, a link state parameter is defined to capture the link reliability on continuing to keep the end-to-end delay into constraint; then, on the basis of this parameter, a routing metric is for- mulated and a routing scheme is designed for balancing the reliability in delay bound guarantee among paths and building a path maximizing the network utility expectation. While the UMR algo- rithm has many advantages, it may result in a higher blocking rate of new calls. This phenomenon is discussed and a weight factor is introduced into UMR to provide a flexible performance option for network operator. A set of simulations are conducted to verify the good performance of UMR, in terms of balancing the traffic distribution on inter-satellite links, reducing the flow interruption rate, and improving the network utility. 展开更多
关键词 Delay bound LEO satellite networks MICRO-SATELLITE Network utility QoS routing
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Low-income and overweight in China:Evidence from a life-course utility model 被引量:3
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作者 REN Yan-jun Bente Castro Campos +1 位作者 Jens-Peter Loy Stephan Brosig 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2019年第8期1753-1767,共15页
Previous literature has demonstrated that low-income people are more likely to settle for poor health choices in developed countries. By using income as a budget constraint and signal for future wellbeing in a life-co... Previous literature has demonstrated that low-income people are more likely to settle for poor health choices in developed countries. By using income as a budget constraint and signal for future wellbeing in a life-course utility model, we examine the association amongst income and overweight. The data used for this study are from the China Health and Nutrition Survey(CHNS). Estimations are conducted for overweight initiation, cessation, and participation mirroring a decision to begin and a past decision to not terminate. Our findings propose that body weight and the likelihood of overweight commencement rise with additional income but at a diminishing degree, representing a concave relation;while the likelihood of overweight discontinuance declines with additional income but at an accelerating degree, suggesting a convex relation.We presume that, as opposed to developed countries, low-income people are less inclined to be overweight in China, a country in transition. This could be explained by an income constraint for unhealthy foodstuff. Nevertheless, it will switch when income surpasses the critical threshold of the concave or inverted U-shape curve indicating that low-income people appear to receive not as much utility from future health. Specifically, this adjustment seems to occur earlier for females and inhabitants of urban areas. 展开更多
关键词 LOW-INCOME OVERWEIGHT LIFE-COURSE utility China
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Utility function based fair data scheduling algorithm for OFDM wireless network 被引量:3
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作者 Guo Kunqi Sun Lixin Jia Shilou 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2007年第4期731-738,共8页
A system model is formulated as the maximization of a total utility function to achieve fair downlink data scheduling in multiuser orthogonal frequency division multiplexing (OFDM) wireless networks. A dynamic subca... A system model is formulated as the maximization of a total utility function to achieve fair downlink data scheduling in multiuser orthogonal frequency division multiplexing (OFDM) wireless networks. A dynamic subcarrier allocation algorithm (DSAA) is proposed, to optimize the system model. The subcarrier allocation decision is made by the proposed DSAA according to the maximum value of total utility function with respect to the queue mean waiting time. Simulation results demonstrate that compared to the conventional algorithms, the proposed algorithm has better delay performance and can provide fairness under different loads by using different utility functions. 展开更多
关键词 OFDM SCHEDULING ALGORITHM utility function.
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