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某石油泄漏场地土壤二甲苯空间分布的三维插值

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生态学杂志 2016年第10期35卷 2861-2866页

作者：史广荆耀栋秦明星刘庚山西农业大学资源环境学院山西太谷030801 太原师范学院汾河流域科学发展研究中心太原030012

为精确界定污染场地中污染物三维空间分布范围,本文以中国某石油储罐泄露污染场地为研究对象,采用最近邻点法、反距离加权法及克里金法3种三维空间插值模型,对场地中特征污染物二甲苯进行三维空间插值计算及污染分布表征,比较不同插值... 详细信息

为精确界定污染场地中污染物三维空间分布范围,本文以中国某石油储罐泄露污染场地为研究对象,采用最近邻点法、反距离加权法及克里金法3种三维空间插值模型,对场地中特征污染物二甲苯进行三维空间插值计算及污染分布表征,比较不同插值模型的计算精度,揭示场地中实际受污染土方量。结果表明,反距离加权法预测平均误差为4.94,均方根误差为14.11,其精度明显高于另外2.模型,界定的污染分布范围较符合实际污染情况,通过该方法进行插值后计算受污染土方量为666.2.m^3。研究结果对该类型污染场地污染物空间分布表征和修复治理决策制定提供科学依据。

关键词：污染评价空间分布三维插值二甲苯

Isolated tuberculous ePididymitis in Northwestern China PoPulation:A review of 56 cases

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Isolated tuberculous ePididymitis in Northwestern China PoPu...

第十六届全国泌尿外科学术会议

作者： Wu Chunyun~1,Zou Tiejun~2.Tang Kaifa~2. Sun Ping~2.0} JunPing~2. 1.DePartment of Sanitation and AntiePidemic,2.DePartment of Urology,The First Affiliated HosPital,Xi’an Jiaotong University,School of Medicine 710061

Objective:To describe the clinical characteristics of isolated tuberculous ePididymitis and to Profile its diagnosis and treatment in this grouP of ***:A retrosPective case study of the hosPital records of Patients

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两段加氢生产溶剂油工艺优化

现代化工 2018年第4期38卷 186-188,190页

作者：王成邵春宇姚劲唐明兴新疆寰球工程公司新疆乌鲁木齐830019 中国科学院山西煤炭化学研究所山西太原030001

通过实验确定了抽余油一段、二段加氢所需氢油体积比,一段氢油体积比50~100,二段2.0~300。针对目前抽余油两段加氢工艺存在的一段高温低氢油体积比、二段低温高氢油体积比的特点,提出两段加氢工艺改进方案。采用分别控制一段、二段氢油... 详细信息

通过实验确定了抽余油一段、二段加氢所需氢油体积比,一段氢油体积比50~100,二段2.0~300。针对目前抽余油两段加氢工艺存在的一段高温低氢油体积比、二段低温高氢油体积比的特点,提出两段加氢工艺改进方案。采用分别控制一段、二段氢油体积比的方法降低系统能耗。利用Aspen Plus流程模拟软件模拟了改进前后3种工况下系统温度、能耗等变化,结果显示系统能耗降低11.6%~2..8%。

关键词：抽余油加氢苯加氢节能减排工艺优化

Artificial Neural Networks:Current Applications in Modern Medicine

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Artificial Neural Networks:Current Applications in Modern Me...

Needs and challenges of optical atmospheric monitoring on the background of carbon neutrality in China

2.10 International Conference on Computer and Communication Technologies in Agriculture Engineering (CCTAE 2.10)

作者： SHI Lei 1 2.1. Information Science and Technology College Dalian Maritime University Dalian 11602. China WANG xing-cheng 1 2. College of Information Science and Engineering Bohai University Jinzhou 12.000 China.

Artificial neural networks （ANNs） are a form of artificial computer intelligence which are the mathematical algorithms, generated by computers. They are the digitized model of biological brain and can detect complex nonlinear relationships between dependent as well as independent variables in a data where human brain may fail to detect. Nowadays, ANNs are widely used for medical applications in various disciplines of medicine such as diagnosis, electronic signal analysis, medical image analysis and radiology. In this paper, authors have summarized various applications of ANNs in modern medicine.

关键词： Artificial neural networks application medicine

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Frontiers of Environmental Science & Engineering 2024年第6期18卷 49-62页

作者： Wenqing Liu Chengzhi xing Anhui Institute of Optics and Fine Mechanics Hefei Institutes of Physical ScienceChinese Academy of SciencesHefei 23001China

The achievement of the targets of coordinated control of PM2.5 and O3 and the carbon peaking and carbon neutrality depend on the development of pollution and greenhouse gas monitoring *** monitoring technology,based on its technical characteristics of high scalability,high sensitivity and wide-targets detection,has obvious advantages in pollution/greenhouse gases monitoring and has become an important direction in the development of environmental monitoring *** present,a system of environmental optical monitoring technology with differential optical absorption spectroscopy(DOAS),cavity ring-down spectroscopy(CRDS),light detection and ranging(LIDAR),laser heterodyne spectroscopy(LHS),tunable diode laser absorption spectroscopy(TDLAS),fourier transform infrared spectroscopy(FTIR)and fluorescence assay by gas expansion(FAGE)as the main body has been ***,with the promotion of“reduction of pollution and carbon emissions”strategy,there have been significant changes in the sources of pollution/greenhouse gases,emission components and emission concentrations,which have put forward new and higher requirements for the development of monitoring *** the future,we should pay more attention to the development of new optical monitoring techniques and the construction of stereoscopic monitoring system,the interdisciplinarity(among mathematics,physics,chemistry and biology,etc.),and the monitoring of greenhouse gases and research on atmospheric chemistry.

关键词： Pollution Greenhouse gas Optical atmospheric monitoring Needs and challenges

Distributed Fault-Tolerant Control of Uncertain Multi-Agent Systems with Connectivity Maintenance

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Journal of Systems Science & Complexity 2024年第1期37卷 40-62页

作者： xing Xueyan HU Guoqiang Continental-NTU Corporate Lab Nanyang Technological UniversitySingapore 639798Singapore Continental-NTU Corporate Lab and the School of Electrical and Electronic Engineering Nanyang Technological UniversitySingapore 639798Singapore

In this paper,a distributed cooperative control protocol is presented to deal with actuator failures of multi-agent systems in the presence of connectivity *** the developed strategy,each agent can track the reference trajectory of the leader in the presence of actuator failures,disturbances and *** connectivity of the multi-agent system can always be ensured during the control *** achieve the aforementioned control objectives,a potential function is introduced to the distributed adaptive fault-tolerant control algorithm to preserve the initial connected network among the *** uncertainty of the multi-agent system,which is allowed to be described by discontinuous functions,is approximated and compensated using the fuzzy logic *** asymptotic stability of the closed-loop system is demonstrated through the use of Cellina’s approximate selection theorem of nonsmooth *** to the developed adaptive laws,the upper bound of the disturbance is allowed to be uncertain,which facilitates the implementation of the control ***,simulation results are provided to verify the effectiveness of the proposed control scheme.

关键词： Actuator failure connectivity maintenance coordination control uncertainties

Reinforcement Learning-Based Dynamic Order Recommendation for On-Demand Food Delivery

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Tsinghua Science and Technology 2024年第2期29卷 356-367页

作者： xing Wang Ling Wang Chenxin Dong Hao Ren Ke xing Department of Automation Tsinghua UniversityBeijing 100080China School of Mechanical and Automotive Engineering Qingdao Hengxing University of Science and TechnologyQingdao 266100China Meituan Beijing 100015China

On-demand food delivery(OFD)is gaining more and more popularity in modern *** a kernel order assignment manner in OFD scenario,order recommendation directly influences the delivery efficiency of the platform and the delivery experience of *** paper addresses the dynamism of the order recommendation problem and proposes a reinforcement learning solution *** actor-critic network based on long short term memory(LSTM)unit is designed to deal with the order-grabbing conflict between different ***,three rider sequencing rules are accordingly proposed to match different time steps of the LSTM unit with different *** test the performance of the proposed method,extensive experiments are conducted based on real data from Meituan delivery *** results demonstrate that the proposed reinforcement learning based order recommendation method can significantly increase the number of grabbed orders and reduce the number of order-grabbing conflicts,resulting in better delivery efficiency and experience for the platform and riders.

关键词： on-demand food delivery order recommendation reinforcement learning actor-critic network long short term memory

Dynamic plugging regulating strategy of pipeline robot based on reinforcement learning

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Petroleum Science 2024年第1期21卷 597-608页

作者： xing-Yuan Miao Hong Zhao College of Mechanical and Transportation Engineering China University of PetroleumBeijing102249China

Pipeline isolation plugging robot (PIPR) is an important tool in pipeline maintenance operation. During the plugging process, the violent vibration will occur by the flow field, which can cause serious damage to the pipeline and PIPR. In this paper, we propose a dynamic regulating strategy to reduce the plugging-induced vibration by regulating the spoiler angle and plugging velocity. Firstly, the dynamic plugging simulation and experiment are performed to study the flow field changes during dynamic plugging. And the pressure difference is proposed to evaluate the degree of flow field vibration. Secondly, the mathematical models of pressure difference with plugging states and spoiler angles are established based on the extreme learning machine (ELM) optimized by improved sparrow search algorithm (ISSA). Finally, a modified Q-learning algorithm based on simulated annealing is applied to determine the optimal strategy for the spoiler angle and plugging velocity in real time. The results show that the proposed method can reduce the plugging-induced vibration by 19.9% and 32.7% on average, compared with single-regulating methods. This study can effectively ensure the stability of the plugging process.

关键词： Pipeline isolation plugging robot Plugging-induced vibration Dynamic regulating strategy Extreme learning machine Improved sparrow search algorithm Modified Q-learning algorithm

Research on the influences of motion characteristics of jetting projectile charge under water

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Defence Technology（防务技术） 2024年第3期33卷 411-425页

作者： xing Chen Yong-gang Lu Institute of Systems Engineering China Academy of Engineering PhysicsMianyang 621900SichuanChina

Shaped charge warhead is important for enhancing the damage performance of underwater *** paper used finite element analysis software and based on JPC water penetration experiments to examine the influence of liner parameters(wall thickness,material),charge aspect ratio,and stand-off distance on the movement characteristics of JPC in *** findings reveal that the head diameter of the JPC increases and experiences significant erosion after entering the water,the effective length of the JPC in water undergoes two distinct phases:a growth phase and a decrease phase,with the velocity of the JPC decaying *** the liner thickness,stand-off distance and the charge aspect ratio can improve the erosion resistance and the velocity retention capacity of the *** optimal ranges for liner thickness and stand-off distance are 0.0363D_(k) to 0.0545D_(k)(D_(k) is the charge diameter),the stand-off distance should be within 1.0D_(k).After the charge aspect ratio higher than 1.2.,the charge structure exerts minimal influence the movement characteristics of the JPC in *** density plays a crucial role in the velocity decay pattern of the JPC during *** with higher densities exhibit superior velocity retention capabilities in water,with the velocity decay pattern converging if the densities are ***,copper,tantalum and tungsten liners are deemed appropriate for underwater shaped charge ***,the results will provide an important reference for the design of underwater shaped charge warhead.

关键词： JPC Movement characteristics Underwater penetration Numerical simulation