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Quantum simulation meets quantum biology

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Science China(Physics,Mechanics & Astronomy) 2017年第3期60卷 87-88页

作者： jianming cai School of Physics & Center for Quantum Optical Science Huazhong University of Science and Technology Wuhan 430074 China

Quantum biology has attracted increasing interest in recent years [1]. It is remarkable that quantum effect such as quantum coherence and entanglement has been found existing in several examples of biological processe... 详细信息

关键词：量子生物学量子模拟量子效应生物过程量子纠缠量子相干

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帕金森神经网络建模及核团数字电路设计

中国科学：技术科学 2024年第8期54卷 1586-1600页

作者：蔡建明包涵边逸轩徐权陈墨包伯成常州大学微电子与控制工程学院常州213159

已有的帕金森神经网络模型并未包含基底神经回路中的所有神经核团.因此,在研究发病机理和寻找最佳深部脑刺激(deep brain stimulation,DBS)的刺激靶点时忽略了其他核团潜在的影响.本文根据基底神经回路结构,利用Hindmarsh-Rose(HR)神经... 详细信息

已有的帕金森神经网络模型并未包含基底神经回路中的所有神经核团.因此,在研究发病机理和寻找最佳深部脑刺激(deep brain stimulation,DBS)的刺激靶点时忽略了其他核团潜在的影响.本文根据基底神经回路结构,利用Hindmarsh-Rose(HR)神经元模型成功构建了完整的帕金森神经网络模型.三种不同外加刺激下的数值仿真结果表明,缺失黑质致密部(substantia nigra pars compacta,SNc)核团的帕金森神经网络会出现神经元高度同步行为和异常β振荡活动,符合目前公认的帕金森发病机理,从而验证了所提的模型的合理性.此外,受生物伦理、实验难度的影响,电子神经网络更适合帕金森DBS治疗方案研究,因此,本文以SNc核团为例在现场可编程逻辑门阵列(field programmable gate array,FPGA)平台上构建了不同外加刺激下的SNc核团数字电路.电路实验结果能完整呈现出与数值仿真一致的放电行为,表明了数字电路设计的正确性.本文所设计的电路占用较低的数字电路资源,为帕金森神经网络电路实现做好基础准备.

关键词：帕金森神经网络 HR神经元模型动力学模型现场可编程逻辑门阵列(FPGA) 神经元同步

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Urban Economic Cluster Template and Its Dynamics of Beijing,China

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Chinese Geographical Science 2014年第6期24卷 740-750页

作者： YANG Zhenshan LIANG Jinshe cai jianming Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing Normal University

Economic clusters have been a central focus of current urban and regional research, policies and practices. However, a methodology to identify and analyze policy-relevant economic cluster dynamics is still not well developed. Based on input-output(I-O) data of 1987, 1992, 1997, 2002 and 2007 of Beijing, this article presents an adapted principle component analysis for identifying the evolution of local economic cluster patterns. This research addresses the changes of economic interaction of industries with complementary and common activities over time. The identified clusters provide an insight into the reality of economic development in a diversifying urban economy: the increasing importance of services and the growing interaction between service and manufacturing industries. Our method therefore provides the analysts with a better understanding of the emergence, disappearance and development of economic clusters citywide. The results could be used to assist monitoring urban economic development and designing more practical urban economic strategies.

关键词： economic clusters industrial linkages urban economic dynamics functional analysis input-output Beijing China

Memristive cyclic three-neuron-based neural network with chaos and global coexisting attractors

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Science China(Technological Sciences) 2022年第11期65卷 2582-2592页

作者： BAO Han CHEN ZhuGuan cai jianming XU Quan BAO BoCheng School of Microelectronics and Control Engineering Changzhou UniversityChangzhou 213164China

It has been documented that a cyclic three-neuron-based neural network with resistive synaptic weights cannot exhibit *** this end,a memristive cyclic three-neuron-based neural network is presented using a memristive weight to substitute a resistive *** memristive cyclic neural network always has five equilibrium points within the parameters of interest,and their stability analysis shows that they are one index-2 saddle-focus,two index-1 saddle-foci,and two stable node-foci,*** analyses are performed for the memristive cyclic neural network by several numerical simulation *** results demonstrate that the memristor synapse-based neural network with the simplest cyclic connection can not only exhibit chaos,but also present global coexisting attractors composed of stable points and unstable periodic or chaotic orbits under different initial ***,with the designed implementation circuit,Multisim circuit simulations and hardware experiments are executed to validate the numerical simulations.

关键词： memristive weight cyclic neural network chaos coexisting attractors hardware experiment

A multi-task deep learning model for short-term taxi demand forecasting considering spatiotemporal dependences

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Journal of Traffic and Transportation Engineering(English Edition) 2021年第1期8卷 83-94页

作者： Huimin Luo jianming cai Kunpeng Zhang Ruihang Xie Liang Zheng School of Traffic and Transportation Engineering Central South UniversityChangsha 410075China College of Electrical Engineering Henan University of TechnologyZhengzhou 450001China

Short-term taxi demand forecasting is of great importance to incentivize vacant cars moving from over-supply regions to over-demand regions,which can minimize the wait time for passengers and *** the consideration of spatiotemporal dependences,this study proposes a multi-task deep learning(MTDL)model to predict short-term taxi demand in multi-zone *** nonlinear Granger causality test is applied to explore the causality relationships among various traffic zones,and long short-term memory(LSTM)is used as the core neural unit to construct the framework of the multi-task deep learning *** addition,several hyperparameter optimization methods(e.g.,grid search,random search,Bayesian optimization,hyperopt)are used to tune the *** the taxi trip data in New York City for validation,the multi-task deep learning model considering spatiotemporal dependences(MTDL*)is compared with the single-task deep learning model(STDL),the full-connected multi-task deep learning model(MTDL#)and other benchmark algorithms(such as LSTM,support vector machine(SVM)and k-nearest neighbors(k-NN)).The experiment results show that the proposed MTDL model is promising to predict short-term taxi demand in multi-zone level,the nonlinear Granger causality analysis is able to capture the spatiotemporal correlations among various traffic zones,and the Bayesian optimization is superior to the other three methods,which verified the feasibility and adaptability of the proposed method.

关键词： Traffic engineering Short-term traffic prediction Deep learning Multi-task model Spatiotemporal dependences

Urban Metabolic Efficiencies and Elasticities of Chinese Cities

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Chinese Geographical Science 2016年第6期26卷 715-730页

作者： SONG Tao cai jianming YANG Zhenshan CHEN Mingxing LIN Jing Institute of Geographical Sciences and Natural Resources Research Chinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China

Urban metabolism is a complex system of materials, energy, population and environment, which usually can be measured by the Emergy Synthesis(ES) and the Slacks-Based Measure(SBM) approach. In this paper, by employing the two approaches of ES and SBM, as well as metabolic evolution index, urban metabolic stocks, efficiencies and elasticity of 31 Chinese cities are evaluated in a systematic way. The results imply that over the last decade(2000–2010), most of the cities, such as Chongqing, Nanjing, Shijiazhuang, Hangzhou, were experiencing drastic urban metabolic efficiency decline accompanied with a moderate decrease of industrial outputs. By contrast, metropolises and specialized cities have improved their urban metabolic performances, with higher output-input ratio and fewer undesirable outputs. However, their exported emergy experienced a substantial increase as well. It is concluded that local urban management might develop policies to diversify urban renewable supplies and address the undesirable output problems. The urban emergy of renewable resources should be specified as a prime focus for future research. In addition, mechanisms of different urban metabolic models will also be necessary for researchers.

关键词： urban metabolism emergy Slacks-Based Measure (SBM) metabolic elasticity

Spatial pattern and its evolution of Chinese provincial population： Methods and empirical study

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Journal of Geographical Sciences 2015年第12期25卷 1507-1520页

作者： DENG Yu LIU Shenghe cai jianming LU Xi Chris P NIELSEN Institute of Geographic Sciences and Natural Resources Research CAS Beijing 100101 China Key Laboratory of Regional Sustainable Development Modeling CAS Beijing 100101 China School of Engineering and Applied Sciences Harvard Cambridge MA 02138 USA

China has been experiencing an unprecedented urbanization process. In 2011, China＇s urban population reached 691 million with an urbanization rate of 51.27%. Urbaniza- tion level is expected to increase to 70% in China in 2030, reflecting the projection that nearly 300 million people would migrate from rural areas to urban areas over this period. At the same time, the total fertility rate of China＇s population is declining due to the combined effect of economic growth, environmental carrying capacity, and modern social consciousness. The Chinese government has loosened its ＂one-child policy＂ gradually by allowing childbearing couples to have the second child as long as either of them is from a one-child family. In such rapidly developing country, the natural growth and spatial migration will consistently reshape spatial pattern of population. An accurate prediction of the future spatial pattern of population and its evolution trend are critical to key policy-making processes and spatial planning in China including urbanization, land use development, ecological conservation and environ- mental protection. In this paper, a top-down method is developed to project the spatial dis- tribution of China＇s future population with considerations of both natural population growth at provincial level and the provincial migration from 2010 to 2050. Building on this, the spatial pattern and evolution trend of Chinese provincial population are analyzed. The results sug- gested that the overall spatial pattern of Chinese population will be unlikely changed in next four decades, with the east area having the highest population density and followed by central area, northeast and west area. Four provinces in the east, Shanghai, Beijing, Tianjin and Jiangsu, will remain the top in terms of population density in China, and Xinjiang, Qinghai and Tibet will continue to have the lowest density of population. We introduced an index system to classify the Chinese provinces into three categori

关键词： China provincial population urbanization migration spatial pattern natural growth

Regional Economic Types and Development Strategy of Small Towns in Suburb Beijing

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Chinese Journal of Population,Resources and Environment 2010年第2期8卷 75-82页

作者： Han Fei cai jianming Liu Junping Institution of Geographic Sciences and Natural Resources Research CAS Beijing 100101 China Graduate School of the Chinese Academy of Sciences Beijing 100039-China Beijing Rural Economy Research Center Beijing 100192 China

The purpose of this article is to classify the regional economic types and development dynamics of small towns in suburb Beijing by applying the classification methods developed by Nelson's method and Location Quotient method into 183 small towns in *** types of small towns are thus identified,including urban agriculture dominated towns,manufacturing dominated towns,service industry dominated towns and comprehensive type towns with balanced economic *** the environment of geographical information system,the spatial distribution pattern of four types of small towns with their evolution trend is *** results indicate that four types of small towns have obvious'core-periphery'spatial structure but with different functional orientations and evolution *** on this,the different development strategies for each type of small towns are summarized,providing a scientific reference for the differentiating planning and development strategies of these small towns.

关键词： suburbs small towns regional economic types development strategy Beijing

Efficiency and Economy of a New Agricultural Rainwater Harvesting System

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Chinese Journal of Population,Resources and Environment 2010年第4期8卷 41-48页

作者： Ji Wenhua cai jianming Marinus van Veenhuizen Institute of Geographic Sciences and Natural Resources Research Chinese Academy of SciencesBeijing 100101China Graduate University of Chinese Academy of Sciences Beijing 100049China ETC-Urban Agriculture Leusden 3830 ABNetherland

Shortage of water is the key limiting factor for agricultural development of *** harvesting(RWH) could provide an alternative water source for greenhouse agriculture,but local natural and socioeconomic conditions challenge the application of the *** article analyses the advantages and disadvantages of different types of greenhouse RWH in Beijing,and describes a new greenhouse RWH system demonstrated in 2008 in Huairou,a suburb district of *** analyses the efficiency,cost-benefit ratios and limiting factors of the new *** results show that with the new system,RWH efficiency can be as high as 66%(of total rainfall) and the rainwater usage rate can reach 69% of total water *** ratio of benefit to cost of government investment can be 1.84,and the ratio of benefit to cost of a farmer's investment could be 1.68 provided the project is designed to save water and also increase ***,the price of groundwater for agriculture directly influences the potential for applying and scaling up the *** the RWH system does not increase the farmers' incomes at the current water price,they will not use it until the water price rises to a critical point,which is determined by external *** article also suggests a number of measures to increase the efficiency of the system in order to apply it on a large scale.

关键词： Beijing greenhouse agriculture rainwater harvesting cost-benefit