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Control-Net网络技术在污水处理厂的应用
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作者 高素萍 张磊 《自动化技术与应用》 2005年第4期37-40,共4页
Control -net网络是一个开放的、高速的、确定性的工业局域网,用于传输对时间有苛刻要求的信息,为对等通信提供实时控制和报文传送。可实现PC机、控制器、操作界面设备、I/O模块等不同设备间的联网通信。网络成功地应用在多种工业自动... Control -net网络是一个开放的、高速的、确定性的工业局域网,用于传输对时间有苛刻要求的信息,为对等通信提供实时控制和报文传送。可实现PC机、控制器、操作界面设备、I/O模块等不同设备间的联网通信。网络成功地应用在多种工业自动控制系统上。 展开更多
关键词 control-net网 工业局域网 实时监控 溶解氧
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Study of the control-equilibrium of control systems
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作者 Liu Qiaoge Fu Mengyin Sun Changsheng 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2008年第4期775-778,共4页
Not so much had been talked about equilibrium in control area. On the basis of the phenomenon of balance, the concept of control-equilibrium and control-equilibrium of a control system is proposed. According to this t... Not so much had been talked about equilibrium in control area. On the basis of the phenomenon of balance, the concept of control-equilibrium and control-equilibrium of a control system is proposed. According to this theory, a perfect control method should not only guarantee stability of the system, but also ensure the control-equilibrium of the system. To achieve the control-equilibrium, feed-forward control is required. 展开更多
关键词 BALANCE control-equilibrium-state control-equilibrium feed-forward control
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基于Control-net网络的污水处理厂管控一体化系统 被引量:1
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作者 高素萍 《中国给水排水》 CAS CSCD 北大核心 2007年第14期59-62,共4页
基于污水处理厂对生产过程控制自动化、管理信息化的要求和计算机网络技术的特点,结合工程实例从系统结构、软件平台、硬件配置、数据库和实现功能几方面对管控一体化系统的设计与实现进行了详细的阐述,指出生产管理自动化是企业管控一... 基于污水处理厂对生产过程控制自动化、管理信息化的要求和计算机网络技术的特点,结合工程实例从系统结构、软件平台、硬件配置、数据库和实现功能几方面对管控一体化系统的设计与实现进行了详细的阐述,指出生产管理自动化是企业管控一体化系统实现的关键环节。 展开更多
关键词 污水处理厂 分布式控制 管控一体化
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Co-effect of Demand-control-support Model and Effort-reward Imbalance Model on Depression Risk Estimation in Humans: Findings from Henan Province of China 被引量:9
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作者 YU Shan Fa NAKATA Akinori +4 位作者 GU Gui Zhen SWANSON Naomi G ZHOU Wen Hui HE Li Hua WANG Sheng 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2013年第12期962-971,共10页
Objective To investigate the co-effect of Demand-control-support (DCS) model and Effort-reward Imbalance (ERI) model on the risk estimation of depression in humans in comparison with the effects when they are used... Objective To investigate the co-effect of Demand-control-support (DCS) model and Effort-reward Imbalance (ERI) model on the risk estimation of depression in humans in comparison with the effects when they are used respectively. Methods A total of 3 632 males and 1 706 females from 13 factories and companies in Henan province were recruited in this cross-sectional study. Perceived job stress was evaluated with the Job Content Questionnaire and Effort-Reward Imbalance Questionnaire (Chinese version). Depressive symptoms were assessed by using the Center for Epidemiological Studies Depression Scale (CES-D). Results DC (demands/job control ratio) and ERI were shown to be independently associated with depressive symptoms. The outcome of low social support and overcommitment were similar. High DC and low social support (SS), high ERI and high overcommitment, and high DC and high ERI posed greater risks of depressive symptoms than each of them did alone. ERI model and SS model seem to be effective in estimating the risk of depressive symptoms if they are used respectively. Conclusion The DC had better performance when it was used in combination with low SS. The effect on physical demands was better than on psychological demands. The combination of DCS and ERI models could improve the risk estimate of depressive symptoms in humans. 展开更多
关键词 DEPRESSION Work-related stress Demand-control-support Effort- reward imbalance
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基于Control-mind数控系统的电液束设备控制功能开发
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作者 李玉麒 叶俊强 《电加工与模具》 2021年第3期35-38,44,共5页
现有的电液束加工设备存在控制可扩展性不够、无对刀功能、加工孔的入口孔型一致性难以得到保证、人工输入及修改数控程序时易出现错误等问题。基于Control-mind数控系统,开发出具有定制界面和特定功能的新电液束加工设备,以满足新的加... 现有的电液束加工设备存在控制可扩展性不够、无对刀功能、加工孔的入口孔型一致性难以得到保证、人工输入及修改数控程序时易出现错误等问题。基于Control-mind数控系统,开发出具有定制界面和特定功能的新电液束加工设备,以满足新的加工工艺需求。 展开更多
关键词 control-mind数控系统 电液束加工 控制功能
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Robust Adaptive Gain Higher Order Sliding Mode Observer Based Control-constrained Nonlinear Model Predictive Control for Spacecraft Formation Flying 被引量:11
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作者 Ranjith Ravindranathan Nair Laxmidhar Behera 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2018年第1期367-381,共15页
This work deals with the development of a decentralized optimal control algorithm, along with a robust observer,for the relative motion control of spacecraft in leader-follower based formation. An adaptive gain higher... This work deals with the development of a decentralized optimal control algorithm, along with a robust observer,for the relative motion control of spacecraft in leader-follower based formation. An adaptive gain higher order sliding mode observer has been proposed to estimate the velocity as well as unmeasured disturbances from the noisy position measurements.A differentiator structure containing the Lipschitz constant and Lebesgue measurable control input, is utilized for obtaining the estimates. Adaptive tuning algorithms are derived based on Lyapunov stability theory, for updating the observer gains,which will give enough flexibility in the choice of initial estimates.Moreover, it may help to cope with unexpected state jerks. The trajectory tracking problem is formulated as a finite horizon optimal control problem, which is solved online. The control constraints are incorporated by using a nonquadratic performance functional. An adaptive update law has been derived for tuning the step size in the optimization algorithm, which may help to improve the convergence speed. Moreover, it is an attractive alternative to the heuristic choice of step size for diverse operating conditions. The disturbance as well as state estimates from the higher order sliding mode observer are utilized by the plant output prediction model, which will improve the overall performance of the controller. The nonlinear dynamics defined in leader fixed Euler-Hill frame has been considered for the present work and the reference trajectories are generated using Hill-Clohessy-Wiltshire equations of unperturbed motion. The simulation results based on rigorous perturbation analysis are presented to confirm the robustness of the proposed approach. 展开更多
关键词 Adaptive gain higher order sliding mode observer leader-follower formation nonlinear model predictive control spacecraft formation flying tracking control
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Quantized Nonlinear Control-A Survey 被引量:11
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作者 JIANG Zhong-Ping LIU Teng-Fei 《自动化学报》 EI CSCD 北大核心 2013年第11期1820-1830,共11页
Quantized control systems design is motivated by the convergence of controls and communications to address modern engineering applications involving the use of information technology. This paper presents an overview o... Quantized control systems design is motivated by the convergence of controls and communications to address modern engineering applications involving the use of information technology. This paper presents an overview of recent developments on the control of linear and nonlinear systems when the control input is subject to quantization or the quantized states or outputs are used as feedback measurements. The co-existence of high-dimeasionality, quantization, nonlinearity and uncertainty poses great challenges to quantized control of nonlinear systems and thus calls for new ideas and techniques. The field of quantized nonlinear control is still at its infancy. Preliminary results in our recent work based on input-to-state stability and cyclic-small-gain theorems are reviewed. The open problems in quantized nonlinear control are also outlined. 展开更多
关键词 Quantized control nonlinear systems input-to-state stability small-gain theorem
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Hierarchical-control-based output synchronization of coexisting attractor networks
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作者 宋运忠 唐贻发 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第2期127-134,共8页
This paper introduces the concept of hierarchical-control-based output synchronization of coexisting attractor networks. Within the new framework, each dynamic node is made passive at first utilizing intra-control aro... This paper introduces the concept of hierarchical-control-based output synchronization of coexisting attractor networks. Within the new framework, each dynamic node is made passive at first utilizing intra-control around its own arena. Then each dynamic node is viewed as one agent, and on account of that, the solution of output synchronization of coexisting attractor networks is transformed into a multi-agent consensus problem, which is made possible by virtue of local interaction between individual neighbours; this distributed working way of coordination is coined as inter-control, which is only specified by the topological structure of the network. Provided that the network is connected and balanced, the output synchronization would come true naturally via synergy between intra and inter-control actions, where the rightness is proved theoretically via convex composite Lyapunov functions. For completeness, several illustrative examples are presented to further elucidate the novelty and efficacy of the proposed scheme. 展开更多
关键词 hierarchical control passive control composite Lyapunov function the Newton--Leipnik equation attractor
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Temperature-control-induced masculinization in tiger puffer Takifugu rubripes
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作者 ZHOU He ZHUANG Zixin +6 位作者 ZHANG Rui XU Qizheng LIANG Yuting JIANG Zhiqiang LI Xia MA Tianyu LI Yajuan 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2019年第3期1125-1135,共11页
This study used tiger puffer Takifugu rubripes to explore new,simple methods for lowtemperature-induced masculinization in a cultured fish without the use of ultraviolet irradiation or sex hormones.An orthogonal test ... This study used tiger puffer Takifugu rubripes to explore new,simple methods for lowtemperature-induced masculinization in a cultured fish without the use of ultraviolet irradiation or sex hormones.An orthogonal test L9(3^4)design was used to consider three factors at three levels:treatment starting times(days post-hatch,dph:factor A)of 20,50 and 80 dph;treatment temperatures(factor B)of 13℃,15℃and 17℃;and treatment durations(factor C)of 30,45 and 60 days.A control group was reared at 21±1℃.The experiments were repeated twice.At 230 dph,the gonads were removed from thirty randomly sampled fish in each group.Histological observations and analysis of single nucleotide polymorphisms(SNP)were used to identified pseudo males,which biological sex was male and genetic sex were female(XX).Treatment group 4(A2B1C2)resulted in the highest proportion of males(75%).According to the intuitive analysis of the orthogonal-array experiments,the optimal combination of lowtemperature-induced masculinization of T.rubripes was A2B1C2.The population sex ratio depended on the three factors in the sequence B→A→C.A comparison of the daily increases in length and weight during and after the low-temperature conditions showed that the absolute daily increases in weight and length were significantly less during treatment than after treatment.Daily increases in weight and length did not significantly differ between the treatment groups and the controls(P>0.05),demonstrating that the growth rate could return to normal after the low-temperature conditions.This study establishes a low-temperatureinduced masculinization technology for T.rubripes and demonstrates that although the growth rate(length and weight)decreased in an array of nine treatment groups during the processing time,it returned to a normal level after processing.The results should serve as a guide for achieving the masculinization of T.rubripes in production. 展开更多
关键词 TAKIFUGU rubripes temperature control MASCULINIZATION ORTHOGONAL test growth RATE
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Linear-control-based synchronization of coexisting attractor networks with time delays
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作者 宋运忠 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第6期162-168,共7页
This paper introduces the concept of linear-control-based synchronization of coexisting attractor networks with time delays. Within the new framework, closed loop control for each dynamic node is realized through line... This paper introduces the concept of linear-control-based synchronization of coexisting attractor networks with time delays. Within the new framework, closed loop control for each dynamic node is realized through linear state feedback around its own arena in a decentralized way, where the feedback matrix is determined through consideration of the coordination of the node dynamics, the inner connected matrix and the outer connected matrix. Unlike previously existing results, the feedback gain matrix here is decoupled from the inner matrix; this not only guarantees the flexible choice of the gain matrix, hut also leaves much space for inner matrix configuration. Synchronization of coexisting attractor networks with time delays is made possible in virtue of local interaction, which works in a distributed way between individual neighbours, and the linear feedback control for each node. Provided that the network is connected and balanced, synchronization will come true naturally, where theoretical proof is given via a Lyapunov function. For completeness, several illustrative examples are presented to further elucidate the novelty and efficacy of the proposed scheme. 展开更多
关键词 linear feedback control Lyapunov function the Newton-Leipnik equation attractor time delays
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Preliminary Study on the Ecological Agriculture Development Model of"Pennisetum sineseRoxb-Rocky Desertification Control-Edible Mushrooms"in Guizhou Province
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作者 senlin zhu aihua zhang +3 位作者 shanyuan wei xu chen muyun du rende yang 《Agricultural Science & Technology》 CAS 2017年第12期2406-2409,共4页
In Guizhou Province, the area of rocky desertification land is 3.023 8 million hm^2, accounting for 17.16% of total area of land in the province. Rocky desertification is the most important ecological problem that res... In Guizhou Province, the area of rocky desertification land is 3.023 8 million hm^2, accounting for 17.16% of total area of land in the province. Rocky desertification is the most important ecological problem that restricts the economic and social development in Guizhou, so the primary task of ecological construction in Guizhou Province is to curb rocky desertification. How to effectively, efficiently and persistently use rocky desertification land is not only the key to the improvement of ecological environment, but also an urgent problem solved for local people's survival and anti-poverty. Due to having developed roots, growing fast, high yield of grass, strong resistance to drought, and high regeneration capacity, Pennisetum sinese Roxb has become a new method to control rocky desertification. How to use P. sinese Roxb efficiently becomes the key to the ecological control of rocky desertification by P. sinese Roxb. In this study, the ecological agriculture development model of "P. sinese Roxb-rocky desertification control-edible mushrooms" was studied, and the effect of cultivating Pleurotus eryngii with P. sinese Roxb in rocky desertification land was analyzed. Moreover, an outlook for the application of P. sinese Roxb in rocky desertification areas of Guizhou was given. 展开更多
关键词 Rocky desertification control Pennisetum sinese Roxb Edible mushrooms Ecological agriculture
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PROCONTROL-P 分散控制系统在深圳西部电厂 300 MW 机组上的应用
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作者 陈德斌 王正军 《中国电力》 EI CSCD 北大核心 1998年第2期44-48,共5页
介绍了ABB公司PROCONTROL-P型分散控制系统(DCS)的特点、基本功能、硬件结构、软件设计及在深圳西部电厂2×300MW机组上的应用情况。实践说明,该系统可靠性较高、功能丰富,可满足大型火电机组监视和控... 介绍了ABB公司PROCONTROL-P型分散控制系统(DCS)的特点、基本功能、硬件结构、软件设计及在深圳西部电厂2×300MW机组上的应用情况。实践说明,该系统可靠性较高、功能丰富,可满足大型火电机组监视和控制要求。 展开更多
关键词 软件设计 分散控制系统 发电厂 锅炉
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ABB Procontrol-P控制系统可靠性分析
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作者 林青 《长沙水电师院学报(自然科学版)》 1999年第1期56-59,共4页
通过系统分析ABBProcontrolP分散控制系统软硬件的可靠性,并结合实际应用情况,得出该控制系统是可靠的。
关键词 控制系统 可靠性 发电厂
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悬挂式全电驱小区精量播种机控制系统的设计与试验 被引量:1
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作者 东忠阁 程睿 +4 位作者 吴泽全 赵尔迪 侯云涛 李占成 蔡晓华 《农机化研究》 北大核心 2026年第3期70-77,共8页
为实现小区播种机高效清种与充种,提升区块行长、区间间隔与播种株距的控制精度,并完成多作业行区块的精确对齐,设计了一套悬挂式全电驱小区播种机智能控制系统。该系统集成RTK差分定位、种盒自动传送、排种器伺服驱动、快速清充种、电... 为实现小区播种机高效清种与充种,提升区块行长、区间间隔与播种株距的控制精度,并完成多作业行区块的精确对齐,设计了一套悬挂式全电驱小区播种机智能控制系统。该系统集成RTK差分定位、种盒自动传送、排种器伺服驱动、快速清充种、电驱变量施肥和人机交互等模块,构建了一套完整的精密播种控制体系。针对地轮滑移和北斗RTK定位更新频率低的问题,提出了动态校正算法,通过RTK信号对地轮速度进行在线辨识与滑移补偿,提升了行进测速和株距、播种控制精度;通过台架试验优化清充种控制时序,提升清种与充种效率;田间试验结合打标装置对小区行长、区间间隔、不同作业方向区块对齐精度和株距一致性进行验证,结果表明:在3.0 km/h作业速度下,品种隔离成功率达到100%,播种株距合格率为93.2%,小区行长和区间道控制误差分别小于5 cm和2 cm,各行区块对齐偏差不超过6 cm。研究为提高小区育种播种的精度与作业可靠性提供了有效的技术支撑。 展开更多
关键词 小区播种机 精准控制 动态校正 快速清充种 控制时序
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“风光水火储一体化”能源基地有功功率实时协调控制策略 被引量:1
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作者 李滨 陆光榛 +2 位作者 李佩杰 阳育德 陆峥 《电力系统自动化》 北大核心 2026年第2期188-196,共9页
在“风光水火储一体化”能源基地中,增强风光发电的可控性以及为电力系统提供优质辅助服务的关键在于各类能源的协调控制。现有控制策略存在分解计算效率低、数据处理慢、结果可靠性差和抽蓄、储能调节裕度的越限预警能力薄弱的问题。为... 在“风光水火储一体化”能源基地中,增强风光发电的可控性以及为电力系统提供优质辅助服务的关键在于各类能源的协调控制。现有控制策略存在分解计算效率低、数据处理慢、结果可靠性差和抽蓄、储能调节裕度的越限预警能力薄弱的问题。为此,文中将一种高效的在线时间序列分解方法OneShotSTL应用到有功调节量时序数据的分析和处理中。该方法通过增量计算策略,仅更新与新数据相关的局部计算,显著提升处理效率和实时性。首先,在跟踪发电计划和辅助调频模式下,采用OneShotSTL方法从有功调节量时序数据中提取趋势项、周期项和残差项,实现火电、可变速抽水蓄能、储能分别与趋势分量、周期分量以及残差分量的精准配对。其次,为保障可变速抽水蓄能和储能的调节裕度,提出基于随机指标的抽水蓄能水库库容、储能荷电状态恢复策略。在此基础上,形成一种能源基地有功功率实时协调控制策略。最后,以中国南方区域某“风光水火储一体化”能源基地为例进行仿真分析,验证所提策略的有效性。 展开更多
关键词 能源基地 实时控制 协调控制 有功调节 调频 风电 光伏
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川西—川中地区须家河组致密砂岩气成藏特征及有利勘探方向 被引量:1
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作者 罗冰 冉崎 +7 位作者 王小娟 郑超 张奥博 谢忱 陈世加 许强 王昌勇 李勇 《天然气地球科学》 北大核心 2026年第1期59-77,共19页
为揭示川西—川中地区须家河组天然气差异富集主控因素,指出下一步有利勘探方向,系统分析了须家河组构造地层演化、烃源条件、储集特征和成藏规律。研究结果表明:①须家河组沉积后经历了印支期、燕山期和喜马拉雅期3期构造运动,形成了... 为揭示川西—川中地区须家河组天然气差异富集主控因素,指出下一步有利勘探方向,系统分析了须家河组构造地层演化、烃源条件、储集特征和成藏规律。研究结果表明:①须家河组沉积后经历了印支期、燕山期和喜马拉雅期3期构造运动,形成了北西向、北东向2组断裂体系,发育须一+须二段、须三段和须五段3套烃源岩,具有烃源岩厚度大、有机质丰度高、热演化程度适中、生气强度大等特征,奠定了须家河组致密气大面积分布的物质基础;②须家河组储层岩性主要为岩屑砂岩,发育粒内溶孔、粒间溶孔以及残余粒间孔等储集空间类型,为裂缝—孔隙型和孔隙型储层;③须家河组致密砂岩气藏主要受源—储—断三元耦合控制,其中烃源岩的分布控制致密气的富集区域和气藏边界,在满足自封闭成藏条件时优质储层控制了天然气富集程度,断裂既可以为天然气垂向运移提供通道,其伴生裂缝又可以沟通孤立孔隙提高储层渗流能力控制高产。综合上述成果,以须三段、须四段和须五段为目标层段,优选了致密气有利富集区,对须家河组下步勘探部署具有重要指导意义。 展开更多
关键词 致密砂岩气 须家河组 成藏控制因素 成藏条件 勘探方向 四川盆地
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深部岩层动力灾害防控基本原理与工程学 被引量:1
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作者 谭云亮 杨生龙 +3 位作者 刘学生 范德源 李学斌 王宇 《采矿与岩层控制工程学报》 北大核心 2026年第1期202-221,共20页
深部煤炭开采已成为必然,研究深部岩层动力灾害发生机理、防控原理及工程技术,对于保障煤矿安全生产、践行煤炭托底保供国家要求具有重要意义。首先,探讨了工作面推进方向覆岩、侧空覆岩、断层切割覆岩3种典型条件下其运动致灾动力学过... 深部煤炭开采已成为必然,研究深部岩层动力灾害发生机理、防控原理及工程技术,对于保障煤矿安全生产、践行煤炭托底保供国家要求具有重要意义。首先,探讨了工作面推进方向覆岩、侧空覆岩、断层切割覆岩3种典型条件下其运动致灾动力学过程,构建了覆岩结构力学模型,解答了覆岩运动诱发巷道动力冲击的力学机制。然后,基于深部岩层结构的复杂性、致灾特征的多样性,提出了岩层空间结构全尺度调控方法,揭示了从巷道围岩局部卸压到区域岩层改性全尺度卸压力学原理。最后,阐明了以覆岩结构改性、上行卸压开采、煤层弱化、煤柱宽度设计、高预应力支护为主要内容的灾害防控基本原理,并开展了多项防治工程实践。实践结果表明,麦垛山煤矿水压致裂后围岩变形量减小了44.61%~46.53%,枣泉煤矿大直径钻孔卸压后煤体位移降低了68.24%~77.78%,大安山煤矿高强吸能支护后两帮变形量减小了62.5%,上行卸压开采和多参量智能化监测预警平台分别在忻州窑矿和新巨龙煤矿取得了成功应用。 展开更多
关键词 动力灾害 岩层结构 力学模型 全尺度防控 工程实践
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宁夏特殊用煤的煤岩煤质煤类特征控制因素与成因类型 被引量:1
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作者 魏迎春 王鑫 +5 位作者 姬晓燕 曹代勇 梁永平 李新 李婧琦 朱文豪 《煤炭科学技术》 北大核心 2026年第1期338-348,共11页
推进煤炭资源从燃料向燃料与原料并重转变,实现煤炭清洁高效利用是21世纪解决能源、资源和环境问题的重要途径,煤炭质量评价是煤炭清洁高效利用的基础性工作,赋存规律及控制因素研究为煤炭质量评价提供科学依据。以煤岩、煤质、煤类的... 推进煤炭资源从燃料向燃料与原料并重转变,实现煤炭清洁高效利用是21世纪解决能源、资源和环境问题的重要途径,煤炭质量评价是煤炭清洁高效利用的基础性工作,赋存规律及控制因素研究为煤炭质量评价提供科学依据。以煤岩、煤质、煤类的成因为切入点,分析了宁夏特殊用煤形成和演变及其控制因素,查明了宁夏特殊用煤分布特征,划分了宁夏特殊用煤的成因类型。结果表明:宁夏太原组、山西组、延安组的沉积环境分别以障壁海岸、湖泊三角洲、冲积平原为主;太原组和山西组泥炭沼泽类型以潮湿森林沼泽和潮湿草本沼泽为主,延安组泥炭沼泽类型以干燥森林沼泽为主;受沉积环境和泥炭沼泽类型共同影响,3套煤层的煤岩、煤质特征存在差异。宁夏煤均受深成变质作用影响,大部分变质程度较低,香山煤田太原组和宁东煤田韦州矿区西部煤叠加了动力变质作用,贺兰山煤田煤叠加了区域岩浆热变质作用,变质程度较高。根据特殊用煤对煤岩、煤质及煤类的要求,分析了宁夏特殊用煤的时空分布特征,优质无烟煤分布在汝箕沟矿区;炼焦用煤主要分布在横城矿区、韦州矿区东部、四股泉矿区、沙巴台矿区、石炭井矿区和石嘴山矿区;液化用煤主要分布在红墩子矿区、鸳鸯湖矿区和灵武矿区;除上述区域外的煤均可作气化用煤。从沉积环境、泥炭沼泽类型和变质作用类型入手,建立了宁夏特殊用煤成因类型划分方案,将宁夏特殊用煤成因类型划分为16种,其中太原组8种、山西组5种、延安组4种(其中太原组和山西组均包含“湖泊三角洲-潮湿森林沼泽-深成变质作用型”这一成因类型)。该成果可为宁夏煤炭清洁高效利用提供理论支撑。 展开更多
关键词 宁夏 特殊用煤 煤质特征 控制因素 成因类型
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面向手机直连的低轨卫星网络通信技术 被引量:1
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作者 李静玲 王显煜 +6 位作者 甄立 孟庆治 梁薇 穆桐 崔涛 李倩 崔万照 《中国空间科学技术(中英文)》 北大核心 2026年第1期1-12,共12页
为突破传统地面通信覆盖限制,构建全时全域无缝连接的手机直连天地一体化服务能力,对手机直连低轨卫星网络通信技术进行了系统性研究。首先阐述了手机直连卫星的应用背景、概念与内涵,继而给出了手机直连低轨卫星的网络架构,以及手机直... 为突破传统地面通信覆盖限制,构建全时全域无缝连接的手机直连天地一体化服务能力,对手机直连低轨卫星网络通信技术进行了系统性研究。首先阐述了手机直连卫星的应用背景、概念与内涵,继而给出了手机直连低轨卫星的网络架构,以及手机直连卫星所服务的个人与企业用户的业务特征及指标要求。针对手机直连低轨卫星三类主要技术路线的发展趋势、优劣势及技术演进进行了具体分析,并指出其发展面临的频谱资源严重受限、链路受限与功率失衡等关键问题与技术挑战,重点阐述了手机直连低轨卫星网络需要突破的频谱资源优化、5G/6G标准化协议演进、超大规模星载天线以及卫星网络资源高效管控关键技术。最后面向未来6G新型业务应用需求,提出了天地一体化网络架构、人工智能(AI)、天基算力网络以及无线通感算融合6G技术对于手机直连低轨卫星网络的新型赋能。上述系统性的阐述与分析,为手机直连低轨卫星网络通信技术的发展提供了切实可行的研究方向。 展开更多
关键词 手机直连低轨卫星 标准化协议演进 星载天线 频谱优化 资源管控
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果园植保装备现状与趋势分析 被引量:1
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作者 王金星 虞得斌 +2 位作者 刘国钊 张宏建 王光明 《农机化研究》 北大核心 2026年第3期284-291,共8页
针对果园植保作业效率低,迫切需要机械化作业以实现节本增效的问题,对近年来国内外果园植保装备的研究进展进行归纳总结,以探明其现状与趋势。首先,从关键元器件、变量植保、机器视觉和自动导航4个角度对果园植保装备的研究现状进行梳理... 针对果园植保作业效率低,迫切需要机械化作业以实现节本增效的问题,对近年来国内外果园植保装备的研究进展进行归纳总结,以探明其现状与趋势。首先,从关键元器件、变量植保、机器视觉和自动导航4个角度对果园植保装备的研究现状进行梳理;其次,从精准施药、无人化作业、地空协同作业和综合防治4个方面对果园植保装备的技术发展趋势进行分析;最后,在总结前人研究的基础上对果园植保装备的未来发展进行展望,以期为果园植保装备的后续发展与产业化提供重要参考。 展开更多
关键词 果园植保 植保装备 精准施药 精准识别 自动导航 综合防治
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