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Controlling factors of high-quality volcanic reservoirs of Yingcheng Formation in the Songnan gas field 被引量:3
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作者 DU Shang SHAN Xuan-long +1 位作者 YI Jian LI Ji-yan 《Journal of Central South University》 SCIE EI CAS CSCD 2018年第4期892-902,共11页
Predicting high-quality volcanic reservoirs is one of the key issues for oil and gas exploration in the Songnan gas field.Core,seismic,and measurement data were used to study the lithologies,facies,reservoir porosity,... Predicting high-quality volcanic reservoirs is one of the key issues for oil and gas exploration in the Songnan gas field.Core,seismic,and measurement data were used to study the lithologies,facies,reservoir porosity,and reservoir types of the volcanic rocks in the Songnan gas field.The primary controlling factors and characteristics of the high-quality volcanic reservoirs of the Yingcheng Formation in the Songnan gas field were investigated,including the volcanic eruptive stage,edifice,edifice facies,cooling unit,lithology,facies,and diagenesis.Stages with more volatile content can form more high-quality reservoirs.The effusive rhyolite,explosive tuff,and tuff lava that formed in the crater,near-crater,and proximal facies and in the high-volatility cooling units of large acidic-lava volcanic edifices are the most favorable locations for the development of the high-quality reservoirs in the Songnan gas field.Diagenesis dissolution,which is controlled by tectonic action,can increase the size of secondary pores in reservoirs.Studying the controlling factors of the high-quality reservoirs can provide a theoretical basis for the prediction and analysis of high-quality volcanic reservoirs. 展开更多
关键词 Songnan gas field Yingcheng Formation high-quality volcanic reservoir controlling factor
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Research of CAN Bus in the Coal Mine Field Data Transmission based on Reliability
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作者 LUO Li 《International Journal of Technology Management》 2014年第8期83-85,共3页
Under the current situation, China' s rapid economic development, various new science, emerge in an endless stream of new technology, under the environment of coal mine industry, seize the opportunity, by virtue of i... Under the current situation, China' s rapid economic development, various new science, emerge in an endless stream of new technology, under the environment of coal mine industry, seize the opportunity, by virtue of its original advantages, coupled with technology introduction and innovation consciousness of the play, ushered in a new period of development, into the modern coal mining era. CAN bus technology is a new technology which has the typical data transmission in coal mining, the introduction of a certain degree of CAN bus technology, not only improve the efficiency of data transmission, at the same time, in terms of reliability and greatly enhance. In this paper, to a certain extent on the introduction of the CAN bus technology, and on this basis, based on the CAN bus in the coal mine field data transmission reliability research and analysis 展开更多
关键词 can bus Underground Coal Mines field bus Control system Data Transmission Reliability
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基于CAN协议的电液控制系统设计开发 被引量:2
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作者 郭爱军 赵海伟 郭文孝 《煤炭技术》 CAS 2024年第1期237-240,共4页
介绍了首次使用CAN总线来控制电液系统,对传统电液控制系统进行简化,阐述了采用CAN总线技术电液控制系统的构造。研究CAN总线通讯协议、CAN管理器、CAN总线阀的控制逻辑基础,采用CAN总线+嵌入式编程的方法,根据CAN管理器实时反馈末端执... 介绍了首次使用CAN总线来控制电液系统,对传统电液控制系统进行简化,阐述了采用CAN总线技术电液控制系统的构造。研究CAN总线通讯协议、CAN管理器、CAN总线阀的控制逻辑基础,采用CAN总线+嵌入式编程的方法,根据CAN管理器实时反馈末端执行元件的动作状态,经过程序进行相应判断处理,将部分功能动作自动化、智能化,实现了锚杆锚护工艺一键支护的功能。 展开更多
关键词 can总线 电液控制 电磁阀控制 现场总线
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Review of Field Weakening Control Strategies of Permanent Magnet Synchronous Motors
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作者 Runze Jing Gaolin Wang +1 位作者 Guoqiang Zhang Dianguo Xu 《CES Transactions on Electrical Machines and Systems》 EI CSCD 2024年第3期319-331,共13页
Due to high power density,high efficiency,and accurate control performance,permanent magnet synchronous motors(PMSMs)have been widely adopted in equipment manufacturing and energy transformation fields.To expand the s... Due to high power density,high efficiency,and accurate control performance,permanent magnet synchronous motors(PMSMs)have been widely adopted in equipment manufacturing and energy transformation fields.To expand the speed range under finite DC-bus voltage,extensive research on field weakening(FW)control strategies has been conducted.This paper summarizes the major FW control strategies of PMSMs,which are categorized into calculation-based methods,voltage closed-loop control methods,and model predictive control related methods.The existing strategies are analyzed and compared according to performance,robustness,and execution difficulty,which can facilitate the implementation of FW control. 展开更多
关键词 Calculation-based methods field weakening control Model predictive control Permanent magnet synchronous motor OVERMODULATION Voltage closed-loop control
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Oscillation of Dzyaloshinskii–Moriya interaction driven by weak electric fields
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作者 陈润泽 曹安妮 +3 位作者 王馨苒 柳洋 杨洪新 赵巍胜 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第2期487-491,共5页
Dzyaloshinskii–Moriya interaction(DMI) is under extensive investigation considering its crucial status in chiral magnetic orders, such as Néel-type domain wall(DW) and skyrmions. It has been reported that the in... Dzyaloshinskii–Moriya interaction(DMI) is under extensive investigation considering its crucial status in chiral magnetic orders, such as Néel-type domain wall(DW) and skyrmions. It has been reported that the interfacial DMI originating from Rashba spin–orbit coupling(SOC) can be linearly tuned with strong external electric fields. In this work, we experimentally demonstrate that the strength of DMI exhibits rapid fluctuations, ranging from 10% to 30% of its original value, as a function of applied electric fields in Pt/Co/MgO heterostructures within the small field regime(< 10-2V/nm). Brillouin light scattering(BLS) experiments have been performed to measure DMI, and first-principles calculations show agreement with this observation, which can be explained by the variation in orbital hybridization at the Co/MgO interface in response to the weak electric fields. Our results on voltage control of DMI(VCDMI) suggest that research related to the voltage control of magnetic anisotropy for spin–orbit torque or the motion control of skyrmions might also have to consider the role of the external electric field on DMI as small voltages are generally used for the magnetoresistance detection. 展开更多
关键词 Dzyaloshinskii-Moriya interaction weak electric field control effect Rashba spin-orbit coupling interfacial orbital hybridization
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Control Effect Evaluation of Herbicides for Malignant Weed Nut Grass in Sugarcane Field
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作者 李文凤 张荣跃 +4 位作者 黄应昆 尹炯 罗志明 王晓燕 单红丽 《Agricultural Science & Technology》 CAS 2016年第6期1391-1394,共4页
In order to screen herbicides with ideal safety characteristics to control malignant weed nut grass in sugarcane field, 20% thifensulfuron methyl WP and 65% MCPA·ametryne·diuron WP were selected for the fiel... In order to screen herbicides with ideal safety characteristics to control malignant weed nut grass in sugarcane field, 20% thifensulfuron methyl WP and 65% MCPA·ametryne·diuron WP were selected for the field efficacy trial. The results showed that 20% thifensulfuron methyl WP and 65% MCPA·ametryne·diuron WP had good control effect on nut grass. The optimum dosage of 20% thifensulfuron methyl WP and 65% MCPA.ametryne-diuron WP was 1 125 g/hm^2 (effective ingredients 225 g) and 3 150 g/hm^2 (effective ingredients 2 047.5 g), respectively. These two herbicides should be dissolved in 675 kg water per hectare and applied in the vigorous growth period of nut grass (height 10-15 cm) with oriented stem leaf spraying. The control effect after 15 days could be above 87.9%. 展开更多
关键词 Sugarcane field Malignant weed Nut grass Herbicide control
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Current status and construction scheme of smart geothermal field technology
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作者 LI Gensheng SONG Xianzhi +2 位作者 SHI Yu WANG Gaosheng HUANG Zhongwei 《Petroleum Exploration and Development》 SCIE 2024年第4期1035-1048,共14页
To address the key problems in the application of intelligent technology in geothermal development,smart application scenarios for geothermal development are constructed.The research status and existing challenges of ... To address the key problems in the application of intelligent technology in geothermal development,smart application scenarios for geothermal development are constructed.The research status and existing challenges of intelligent technology in each scenario are analyzed,and the construction scheme of smart geothermal field system is proposed.The smart geothermal field is an organic integration of geothermal development engineering and advanced technologies such as the artificial intelligence.At present,the technology of smart geothermal field is still in the exploratory stage.It has been tested for application in scenarios such as intelligent characterization of geothermal reservoirs,dynamic intelligent simulation of geothermal reservoirs,intelligent optimization of development schemes and smart management of geothermal development.However,it still faces many problems,including the high computational cost,difficult real-time response,multiple solutions and strong model dependence,difficult real-time optimization of dynamic multi-constraints,and deep integration of multi-source data.The construction scheme of smart geothermal field system is proposed,which consists of modules including the full database,intelligent characterization,intelligent simulation and intelligent optimization control.The connection between modules is established through the data transmission and the model interaction.In the next stage,it is necessary to focus on the basic theories and key technologies in each module of the smart geothermal field system,to accelerate the lifecycle intelligent transformation of the geothermal development and utilization,and to promote the intelligent,stable,long-term,optimal and safe production of geothermal resources. 展开更多
关键词 smart geothermal field intelligent development of geothermal reservoirs application scenario intelligent characterization intelligent simulation intelligent optimization control smart management
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银河麒麟系统下基于缓存队列的CAN驱动设计与实现
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作者 刘丽霞 刘志鹏 +1 位作者 张力 李之乾 《计算机工程与设计》 北大核心 2024年第10期3170-3176,共7页
为使基于FPGA的CAN功能在国产操作系统上得以应用,提出一种在银河麒麟操作系统下基于缓存队列的CAN驱动设计与实现方法。在目前主流的银河麒麟V10操作系统下,利用Linux下PCIe设备驱动架构,设计并实现基于FPGA的国产CAN驱,实现CAN发送、... 为使基于FPGA的CAN功能在国产操作系统上得以应用,提出一种在银河麒麟操作系统下基于缓存队列的CAN驱动设计与实现方法。在目前主流的银河麒麟V10操作系统下,利用Linux下PCIe设备驱动架构,设计并实现基于FPGA的国产CAN驱,实现CAN发送、接收通信功能。使用缓存队列解决CAN使用的SJA1000协议中硬件接收缓存有限可能造成的丢包问题。对比测试结果表明,提出的CAN驱动满足通信应用,性能稳定,无丢包发生。实现成果可以转化为第三方库丰富操作系统内核驱动库。 展开更多
关键词 区域网络控制 驱动 现场可编程门阵列 周边设备高速连接标准 接收缓存 操作系统 通信
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基于“龙芯一号”的国产化CAN总线通信控制器
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作者 张厚义 季睿 +1 位作者 奚煜 王堃 《柴油机》 2024年第2期55-60,共6页
针对斯特林发动机系统控制台设计一种完全国产化的总线通信控制器。基于项目要求和“龙芯一号”芯片的功能,设计以“龙芯一号”为核心的最小系统板和功能板。重点阐述国产化芯片和模块的选型、各硬件功能电路的设计原理、控制器的软件... 针对斯特林发动机系统控制台设计一种完全国产化的总线通信控制器。基于项目要求和“龙芯一号”芯片的功能,设计以“龙芯一号”为核心的最小系统板和功能板。重点阐述国产化芯片和模块的选型、各硬件功能电路的设计原理、控制器的软件框架以及CAN通信的实现过程等。该控制器实现了在1 Mibit/s速率下的CAN通信,数据稳定且通信冗余可靠,可有效实现对多路信号的控制和读取。 展开更多
关键词 斯特林发动机 控制 芯片 现场总线
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Research on Integration of Coal Mine Moni-toring and Control System with Field Bus Control System 被引量:3
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作者 WU Jian-xin DING Ying JIANG Xiu-zhu 《Journal of China University of Mining and Technology》 EI 2006年第1期82-85,共4页
According to the construction of current coal mine monitoring and control systems in China, the paper proposes three kinds of applicable schemes of integrating PLC and DCS systems with field bus technology to digitize... According to the construction of current coal mine monitoring and control systems in China, the paper proposes three kinds of applicable schemes of integrating PLC and DCS systems with field bus technology to digitize the system and to improve the flexibility and extent of the system. Essentially, the paper introduces the integration of FCS on I/O layers. Based on a real coal mine safety-monitoring and control system applied with a CAN field bus, the major technology of system relays and extensions is discussed. We believe that one of the most applicable methods is currently replacing the connection between function-stations and field-sensors with a CAN bus on I/0 layers for system integration. 展开更多
关键词 monitor and control field bus control system can INTEGRATION
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Controlling Fusion of Majorana Fermions in One-Dimensional Systems by Zeeman Field
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作者 邵陆兵 汪子丹 +3 位作者 沈瑞 盛利 王伯根 邢定钰 《Chinese Physics Letters》 SCIE CAS CSCD 2017年第6期96-99,共4页
We propose the realization of Majorana fermions (MFs) on the edges of a two-dimensional topological insulator in the proximity with s-wave superconductors and in the presence of transverse exchange field h. It is sh... We propose the realization of Majorana fermions (MFs) on the edges of a two-dimensional topological insulator in the proximity with s-wave superconductors and in the presence of transverse exchange field h. It is shown that there appear a pair of MFs localized at two junctions and that a reverse in the direction of h can lead to permutation of two MFs. With decreasing h, the MF states can either be fused or form one Dirac fermion on the π-junctions, exhibiting a topological phase transition. This characteristic can be used to detect physical states of MFs when they are transformed into Dirac fermions MFs is also given. localized on the π-junction. A condition of decoupling two 展开更多
关键词 MF controlling Fusion of Majorana Fermions in One-Dimensional systems by Zeeman field
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CANBUS分布式计算机控制系统设计及应用
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作者 陈双叶 赵颖燕 《北京工业大学学报》 CAS CSCD 北大核心 2002年第2期134-137,共4页
介绍了基于CANBUS现场总线的分布式计算机控制系统的硬件构成原理和软件设计方法,并将其应用在锅炉蒸汽热网智能监控系统中.整个系统由工业控制计算机/服务器,网络通讯控制器、现场控制器及远程计算机组成.系统软件采用了Internet/lntra... 介绍了基于CANBUS现场总线的分布式计算机控制系统的硬件构成原理和软件设计方法,并将其应用在锅炉蒸汽热网智能监控系统中.整个系统由工业控制计算机/服务器,网络通讯控制器、现场控制器及远程计算机组成.系统软件采用了Internet/lntranet和Web技术,建立以浏览器/服务器(B/S)为模式的计算机信息管理系统.实际应用表明:该系统具有抗干扰能力强、现场组态容易、网络化程度高、人机界面友好等特点. 展开更多
关键词 现场总线 智能监控 控制器局域网 INTERNET/INTRANET 浏览器/服务器
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基于Fieldbus和FIX聚乙烯催化剂生产监控系统的设计与实现
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作者 姚晓峰 陈晓侠 车忠鹂 《仪器仪表标准化与计量》 2003年第3期33-35,48,共4页
本文根据聚乙烯催化剂生产的特点,提出了一套现场总线监控系统的设计理论和实现方法。文章从上位机和智能仪表组态两方面分别做了论述。系统运行结果证明,该系统提高了生产控制的安全性、稳定性和经济性,同时也提高了生产效率,具有广阔... 本文根据聚乙烯催化剂生产的特点,提出了一套现场总线监控系统的设计理论和实现方法。文章从上位机和智能仪表组态两方面分别做了论述。系统运行结果证明,该系统提高了生产控制的安全性、稳定性和经济性,同时也提高了生产效率,具有广阔的应用前景。 展开更多
关键词 聚乙烯催化剂 现场总线 监控系统 fieldbus FIX 上位机 智能仪表 组态
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Integration system research and development for three-dimensional laser scanning information visualization in goaf 被引量:1
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作者 罗周全 黄俊杰 +2 位作者 罗贞焱 汪伟 秦亚光 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2016年第7期1985-1994,共10页
An integration processing system of three-dimensional laser scanning information visualization in goaf was developed. It is provided with multiple functions, such as laser scanning information management for goaf, clo... An integration processing system of three-dimensional laser scanning information visualization in goaf was developed. It is provided with multiple functions, such as laser scanning information management for goaf, cloud data de-noising optimization, construction, display and operation of three-dimensional model, model editing, profile generation, calculation of goaf volume and roof area, Boolean calculation among models and interaction with the third party soft ware. Concerning this system with a concise interface, plentiful data input/output interfaces, it is featured with high integration, simple and convenient operations of applications. According to practice, in addition to being well-adapted, this system is favorably reliable and stable. 展开更多
关键词 GOAF laser scanning visualization integration system 1 Introduction The goaf formed through underground mining of mineral resources is one of the main disaster sources threatening mine safety production [1 2]. Effective implementation of goaf detection and accurate acquisition of its spatial characteristics including the three-dimensional morphology the spatial position as well as the actual boundary and volume are important basis to analyze predict and control disasters caused by goaf. In recent years three-dimensional laser scanning technology has been effectively applied in goaf detection [3 4]. Large quantities of point cloud data that are acquired for goaf by means of the three-dimensional laser scanning system are processed relying on relevant engineering software to generate a three-dimensional model for goaf. Then a general modeling analysis and processing instrument are introduced to perform subsequent three-dimensional analysis and calculation [5 6]. Moreover related development is also carried out in fields such as three-dimensional detection and visualization of hazardous goaf detection and analysis of unstable failures in goaf extraction boundary acquisition in stope visualized computation of damage index aided design for pillar recovery and three-dimensional detection
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Method for prevention and control of spontaneous combustion of coal seam and its application in mining field 被引量:12
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作者 Wei Lu Ying-Jiazi Cao Jerry C.Tien 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2017年第5期839-846,共8页
Spontaneous combustion of coal seam has been and continues to be a big problem in coal mines. It could pose great threat to the safety of the whole mine and all miners, especially when it occurs in or nearby coal mine... Spontaneous combustion of coal seam has been and continues to be a big problem in coal mines. It could pose great threat to the safety of the whole mine and all miners, especially when it occurs in or nearby coal mines. Besides, environment of area surrounded mines during combustion can be threatened where large amount of toxic gases including CO_2, CO, SO_2 and H_2S can be leased by fire in mine. Hence, it is important and significant for scholars to study the controlling and preventing of the coal seam fire. In this paper, the complicated reasons for the occurrence and development of spontaneous combustion in coal seam are analysed and different models under various air leakage situations are built as well. Based on the model and approximately calculation, the difficulty of fire extinguishment in coal seam is pointed out as the difficulty and poor effect to remove the large amount of heat released. Detailed measurements about backfilling and case analyses are also provided on the basis of the recent ten years' practice of controlling spontaneous combustion in coal seams in China. A technical fire prevention and control method has been concluded as five steps including detection, prevention, sealing, injection and pressure adjustment. However, various backfill materials require different application and environmental factors, so in this paper, analyses and discussion about the effect and engineering application of prevention of spontaneous combustion are provided according to different backfilling technologies and methods. Once the aforementioned fire prevention can be widely applied and regulated in mines, green mining will be achievable concerning mine fire prevention and control. 展开更多
关键词 SPONTANEOUS COMbusTION of COAL PREVENTION and control Pressure adjustment MINING field
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A Type of Language Field Integrated Algorithm Used for Analysis and Control of Complicated System 被引量:7
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作者 Yang Bingru Department of Computer Science and Engineering, University of Science and Technology of Beijing, 100083, P. R. China 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 1998年第1期67-77,共11页
A new concept of language field and its value structure are presented in this paper for the first time and a describing framework is set forth for researching computational model of reasoning. On this basis we have es... A new concept of language field and its value structure are presented in this paper for the first time and a describing framework is set forth for researching computational model of reasoning. On this basis we have established a model of qualitative reasoning of causal relations and fuzzy integrated algorithm. Furthermore we have found a lot of its applications. 展开更多
关键词 Language field Language value structure Intelligence control Safe evaluation.
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Comparison of large deformation failure control method in a deep gob-side roadway: A theoretical analysis and field investigation
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作者 WANG Jiong LIU Peng +2 位作者 HE Man-chao LIU Yi-peng DU Chang-xin 《Journal of Mountain Science》 SCIE CSCD 2023年第10期3084-3100,共17页
Under the dual influence of the mining disturbance of the previous working face and the advanced mining of the working face,the roadway is prone to large deformation,failure,and rockburst.Roadway stabilization has alw... Under the dual influence of the mining disturbance of the previous working face and the advanced mining of the working face,the roadway is prone to large deformation,failure,and rockburst.Roadway stabilization has always significantly influenced deep mining safety.In this article we used the research background of the large deformation failure roadway of Fa-er Coal Mine in Guizhou Province of China to propose two control methods:bolt-cable-mesh+concrete blocks+directional energy-gathering blasting(BCM-CBDE method)and 1st Generation-Negative Poisson’s Ratio(1G NPR)cable+directional energy-gathering blasting+dynamic pressure stage support(πgirder+single hydraulic prop+retractable U steel)(NPR-DEDP method).Meantime,we compared the validity of the large deformation failure control method in a deep gob-side roadway based on theoretical analysis,numerical simulations,and field experiments.The results show that directional energy-gathering blasting can weaken the pressure acting on the concrete blocks.However,the vertical stress of the surrounding rock of the roadway is still concentrated in the entity coal side and the concrete blocks,showing a’bimodal’distribution.BCM-CBDE method cannot effectively control the stability of the roadway.NPR-DEDP method removed the concrete blocks.It shows using the 1G NPR cable with periodic slipping-sticking characteristics can adapt to repeated mining disturbances.The peak value of the vertical stress of the roadway is reduced and transferred to the deep part of the surrounding rock mass,which promotes the collapse of the gangue in the goaf and fills the goaf.The pressure of the roadway roof is reduced,and the gob-side roadway is fundamentally protected.Meantime,the dynamic pressure stage support method withπgirder+single hydraulic prop+retractable U steel as the core effectively protects the roadway from dynamic pressure impact when the main roof is periodically broken.After the on-site implementation of NPR-DEDP method,the deformation of the roadway is reduced by more than 45%,and the deformation rate is reduced by more than 50%. 展开更多
关键词 Deep gob-side roadway Deformation failure control Roof structure mechanical model Stress field distribution Mining safety .Failure mode.
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Design and analysis of an advanced thermal management system for the solar close observations and proximity experiments spacecraft 被引量:1
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作者 Liu Liu Kangli Bao +4 位作者 Jianchao Feng Xiaofei Zhu Haoyu Wang Xiaofeng Zhang Jun Lin 《Astronomical Techniques and Instruments》 CSCD 2024年第1期52-61,共10页
In this paper,the mission and the thermal environment of the Solar Close Observations and Proximity Experiments(SCOPE)spacecraft are analyzed,and an advanced thermal management system(ATMS)is designed for it.The relat... In this paper,the mission and the thermal environment of the Solar Close Observations and Proximity Experiments(SCOPE)spacecraft are analyzed,and an advanced thermal management system(ATMS)is designed for it.The relationship and functions of the integrated database,the intelligent thermal control system and the efficient liquid cooling system in the ATMS are elaborated upon.For the complex thermal field regulation system and extreme space thermal environment,a modular simulation and thermal field planning method are proposed,and the feasibility of the planning algorithm is verified by numerical simulation.A solar array liquid cooling system is developed,and the system simulation results indicate that the temperatures of the solar arrays meet the requirements as the spacecraft flies by perihelion and aphelion.The advanced thermal management study supports the development of the SCOPE program and provides a reference for the thermal management in other deep-space exploration programs. 展开更多
关键词 Solar Close Observations and Proximity Experiments Adaptive thermal control method Thermal field planning method Pumped liquid cooling system Advanced thermal management system
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Comparative Analysis of Tunnel Seepage Field under Different Waterproof and Drainage System Using Analytical Methods 被引量:5
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作者 Serges Mendomo Meye Zhenzhong Shen 《Engineering(科研)》 2020年第6期401-423,共23页
Tunnel seepage is an important factor affecting the progress and safety of tunnel construction. In this paper, the mining method tunnel construction in the water-rich weathered granite stratum is taken as the research... Tunnel seepage is an important factor affecting the progress and safety of tunnel construction. In this paper, the mining method tunnel construction in the water-rich weathered granite stratum is taken as the research object. Through the analytical calculation method, the distribution law of tunnel seepage field under different waterproof and drainage types is studied, and the comparative analysis is carried out. According to the analytical solution, the influencing factors of grouting parameters are proposed. The sensitivity of the tunnel seepage field to the variation of grouting parameters is analyzed. A novel waterproof and drainage system, and construction technology suitable for subway tunnels with large buried depth below groundwater level were proposed. 展开更多
关键词 Seepage field WATERPROOF Analytical Solutions TUNNEL Controlled Drainage
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A novel fuzzy logic direct torque controller for a permanent magnet synchronous motor with a field programmable gate array 被引量:1
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作者 陈永军 《Journal of Chongqing University》 CAS 2008年第3期228-233,共6页
A high-performance digital servo system built on the platform of a field programmable gate array (FPGA),a fully digitized hardware design scheme of a direct torque control (DTC) and a low speed permanent magnet synchr... A high-performance digital servo system built on the platform of a field programmable gate array (FPGA),a fully digitized hardware design scheme of a direct torque control (DTC) and a low speed permanent magnet synchronous motor (PMSM) is proposed. The DTC strategy of PMSM is described with Verilog hardware description language and is employed on-chip FPGA in accordance with the electronic design automation design methodology. Due to large torque ripples in low speed PMSM,the hysteresis controller in a conventional PMSM DTC was replaced by a fuzzy controller. This FPGA scheme integrates the direct torque controller strategy,the time speed measurement algorithm,the fuzzy regulating technique and the space vector pulse width modulation principle. Experimental results indicate the fuzzy controller can provide a controllable speed at 20 r min-1 and torque at 330 N m with satisfactory dynamic and static performance. Furthermore,the results show that this new control strategy decreases the torque ripple drastically and enhances control performance. 展开更多
关键词 fuzzy control direct torque control field programmable gate array permanent magnet synchronous motor
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