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Surrounding Rock Control Technology of Strong Dynamic Pressure Roadway in Hudi Coal Industry
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作者 Yixue Jia 《World Journal of Engineering and Technology》 2024年第2期362-372,共11页
Aiming at the problems of large deformation and difficult maintenance of deep soft rock roadway under the influence of high ground stress and strong dynamic pressure, taking the surrounding rock control of 1105 lane i... Aiming at the problems of large deformation and difficult maintenance of deep soft rock roadway under the influence of high ground stress and strong dynamic pressure, taking the surrounding rock control of 1105 lane in Hudi Coal Industry as an example, the deformation characteristics and surrounding rock control measures of deep soft rock roadway are analyzed and discussed by means of geological data analysis, roadway deformation monitoring, rock crack drilling and field test. The results show that the main causes of roadway deformation are high ground stress, synclinal tectonic stress, advance mining stress, roadway penetration and surrounding rock fissure development. Based on the deformation characteristics and mechanism of lane 1105, the supporting countermeasures of “roof synergic support, layered grouting, anchor cable beam support, closed hardening of roadway surface” are proposed, which can provide reference for the control of deep roadway surrounding rock under similar conditions. 展开更多
关键词 deep Roadway Combined Support Surrounding Rock control Soft Rock Roadway
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Malnutrition Assessed Using the Geriatric Nutritional Risk Index Is Associated with Preoperative Incidence of Deep Vein Thrombosis in Japanese Patients Undergoing Total Knee Arthroplasty
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作者 Taizo Kaneko Kentaro Hayakawa Tsuyoshi Miyazaki 《Open Journal of Orthopedics》 2024年第8期355-365,共11页
Purpose: Few studies have evaluated the association between malnutrition and the risk of preoperative deep vein thrombosis (DVT) in patients undergoing primary total joint arthroplasty. This study aimed to investigate... Purpose: Few studies have evaluated the association between malnutrition and the risk of preoperative deep vein thrombosis (DVT) in patients undergoing primary total joint arthroplasty. This study aimed to investigate the prevalence of preoperative DVT in Japanese patients undergoing total knee arthroplasty (TKA) and the importance of malnutrition in the risk of preoperative DVT. Methods: We retrospectively analyzed 394 patients admitted for primary TKA at our institution between January 2019 and December 2023. All patients scheduled for TKA at our institution had serum D-dimer levels measured preoperatively. Lower-limb ultrasonography was examined to confirm the presence of DVT in patients with D-dimer levels ≥ 1.0 µg/mL or who were considered to be at high risk of DVT by the treating physician. Based on the results of lower-limb ultrasonography, all patients were divided into the non-DVT and DVT groups. The incidence of and risk factors for preoperative DVT were investigated, as well as the correlation of DVT with the patient’s nutritional parameters. We used two representative tools for nutritional assessment: the Geriatric Nutritional Risk Index (GNRI) and Controlling Nutritional Status Score. Results: The mean age was 77.8 ± 6.9 years. Preoperative DVT was diagnosed in 57 of the 394 (14.5%) patients. Multivariate logistic regression analysis showed that advanced age and malnutrition status, assessed using the GNRI, were independent risk factors for preoperative DVT. Conclusion: A high incidence of preoperative DVT was observed in patients who underwent TKA. Malnutrition status, as assessed using the GNRI, increased the risk of preoperative DVT. Our findings suggest that clinicians should consider these factors when tailoring preventive strategies to mitigate DVT risk in patients undergoing TKA. 展开更多
关键词 MALNUTRITION Geriatric Nutritional Risk Index controlling Nutritional Status Score PREOPERATIVE deep Vein Thrombosis Total Knee Arthroplasty
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Researches on the PAM/Cr^3+ Gel for Deep Profile Control 被引量:1
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作者 ChangXuejun LiuXuejun +1 位作者 WangQunyi GaoShusheng 《Petroleum Science》 SCIE CAS CSCD 2004年第1期65-69,共5页
The profile control hard-gel is composed of polyarylamide (5-6g/L), whose molecular weight is 4,000,000 - 7,000,000 and hydrolysis degree is 17.6%, and cross-linking oxidation-reduction agent (Na2Cr2O7 + NH4Cl), with ... The profile control hard-gel is composed of polyarylamide (5-6g/L), whose molecular weight is 4,000,000 - 7,000,000 and hydrolysis degree is 17.6%, and cross-linking oxidation-reduction agent (Na2Cr2O7 + NH4Cl), with an delayed organic acid crosslinker which contains lactic acid/propionic acid/ethanoic acid and ethylene glycol. After research of the influence factors, such as pH, temperature, salinity and the dosage of delayed crosslinker, the optimum condition(pH 5.2, temperature 55℃, salinity < 7g/L) was found. Gelation time (12-144h) can be controlled by adjusting the dosage of the delayed crosslinker. Deep profile control experiments are carried out on heterogeneous models, which contains three serial high permeable and low permeable cores arranged in a parallel. After water flooding (total recovery, 24.3%), the first, second and third high-permeable cores each are sealed in turn by the profile control agent, and the total displacement recovery increases to 46.8%, 62.2% and 69.1% respectively. So, the greater the sealed depth, the larger the enhancing recovery will be. Finally, the oil displacement mechanisms of deep profile control are discussed. 展开更多
关键词 deep profile control hard-gel delayed cross-linker gelation time heterogeneous model sealed depth
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PREDICTION AND CONTROL OF ROCKBURST DURING DEEP EXCAVATION OF A GOLD MINE IN CHINA 被引量:1
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作者 Zhang Guang,Chen Jingxi,Hu Bin (Institute of Rock and Soil Mechanics,The Chinese Academy of Sciences, Wuhan 430071 China) 《岩石力学与工程学报》 EI CAS CSCD 北大核心 2003年第10期1607-1612,共6页
The studies of prediction and control of rockburst are presented during deep excavation in a gold mine in China. Firstly,the stress-relief method is used to obtain a vast amount of data about initial geostress. Second... The studies of prediction and control of rockburst are presented during deep excavation in a gold mine in China. Firstly,the stress-relief method is used to obtain a vast amount of data about initial geostress. Secondly,3D FEM analyses of large scale are performed to find out the law of geostress distribution at various excavation levels of the mining area. At the same time,as an equally important measure,six typical kinds of rock blocks are sampled for the experimental study of rockburst tendency. According to the synthesized results of the theoretical and testing results,the methods of brittleness coefficient,brittle index and stress,and so on,are adopted. Finally,the evaluation on the possibility of rockbursts is given that may take place at the deep mining area and some effective measures are put forward to prevent and control the rockburst. 展开更多
关键词 中国 金矿 开挖 岩爆预报 控制
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Double-directional control bolt support technology and engineering application at large span Y-type intersections in deep coal mines 被引量:13
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作者 GUO, Zhibiao SHI, Jianjun +2 位作者 WANG, Jiong CAI, Feng WANG, Fuqiang 《Mining Science and Technology》 EI CAS 2010年第2期254-259,共6页
Under deep and complex geological conditions,severe deformation occurs at intersection points of Y-type roadways with large cross sections during engineering projects in coal mines,especially at junction arches.Based ... Under deep and complex geological conditions,severe deformation occurs at intersection points of Y-type roadways with large cross sections during engineering projects in coal mines,especially at junction arches.Based on in-situ investigations and theoretical studies,we have summarized typical forms of destruction and identified high stress and unrestricted support at both sides of junction arch as its main causes.In this study,we also presented double-directional control bolt support technology for a large Y-type span intersection,applied to deep intersection engineering in the Jiahe Coal Mine,which has proved effective. 展开更多
关键词 Y-type intersection double-directional control bolt support deep coal mines
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Tunnel Surrounding Rock Deformation Characteristics and Control in Deep Coal Mining 被引量:2
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作者 Zhiqiang Zhao Housheng Jia +1 位作者 Bo Peng Yangyang Dong 《Geomaterials》 2013年第1期24-27,共4页
In order to study the failure characteristics and control method of deep tunnel surrounding rock, based on the stress test, the structure and stress state of the main transportation tunnel surrounding rock in Mine Zha... In order to study the failure characteristics and control method of deep tunnel surrounding rock, based on the stress test, the structure and stress state of the main transportation tunnel surrounding rock in Mine Zhaogezhuang level 14 was analyzed, and it shows that the surrounding rock is exposed to an interphase hard and soft disadvantageous structure state and complex high stress repeated addition area;Through the theoretical analysis and the statistical data, the relation between the tunnel stress transformation and the surrounding rock deformation was proposed;Through the numerical simulation of the tunnel surrounding rock failure process with the help of RFPA procedure, the results show that the damage of the transportation tunnel level 14 mainly occurs in the bottom and the two coal ribs, and the failure process is spreading from the bottom to the two coal ribs, and the effect of the surrounding rock deformation control is obvious by using the way of 2.5 m anchor with 1.0 m grouting strengthening. 展开更多
关键词 deep TUNNEL SURROUNDING ROCK control Stress TRANSFORMATION DEFORMATION Characteristics
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面向ICS的CGAN-DEEPFOREST入侵检测 被引量:1
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作者 郑灿伟 李世明 +3 位作者 王禹贺 杜军 倪蕴涛 赵艳 《小型微型计算机系统》 CSCD 北大核心 2023年第4期868-874,共7页
随着工业化与信息化的深度融合,工业控制系统(ICS)的安全问题广受关注,ICS领域出现了许多入侵检测模型.但是,现存模型存在局限性,无法同时解决数据不平衡、分类时间长、小样本检测率低和准确率低的问题.因此,本文提出CGAN-DeepForest入... 随着工业化与信息化的深度融合,工业控制系统(ICS)的安全问题广受关注,ICS领域出现了许多入侵检测模型.但是,现存模型存在局限性,无法同时解决数据不平衡、分类时间长、小样本检测率低和准确率低的问题.因此,本文提出CGAN-DeepForest入侵检测模型解决上述问题.首先,采用改进的条件生成对抗网络(CGAN)定向扩充数据来改善数据的不平衡性.其次,采用随机森林对平衡后的数据集进行特征提取,降低分类模型训练时间和分类时间.再次,采用深度森林(DeepForest)进行分类,提高小样本检测率和整体准确率,输出分类结果.最后,使用数据集Gas验证模型效果.实验结果表明,本文模型与简单深度森林模型相比准确率整体提升3%,小样本数据NMRI、MFCI、Dos的查全率、查准率、F1分别提高至95%、84%、90%;与随机森林模型相比,准确率整体提高6%,小样本NMRI的查全率提升23%;与深度卷积神经网络相比,准确率接近94%时,模型训练时间和分类时间提高约50%. 展开更多
关键词 工业控制系统 入侵检测 CGAN-deep Forest 不平衡性 分类时间
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Path Following Control of A Deep-Sea Manned Submersible Based upon NTSM 被引量:7
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作者 马岭 崔维成 《China Ocean Engineering》 SCIE EI 2005年第4期625-636,共12页
In this paper, a robust path following control law is proposed for a deep-sea manned submersible maneuvering along a predeterminated path. Developed in China, the submersible is underactuated in the horizontal plane i... In this paper, a robust path following control law is proposed for a deep-sea manned submersible maneuvering along a predeterminated path. Developed in China, the submersible is underactuated in the horizontal plane in that it is actuated by two perpendicular thrusts in this plane. The advanced non-singular terminal sliding mode (NTSM) is implemented for the design of the path following controller, which can ensure the convergence of the motion system in finite time and improve its robustness against parametric uncertainties and environmental disturbances. In the process of controller design, the close-loop stability is considered and proved by Lyapunov' s stability theory. With the experimental data, numerical simulations are provided to verify the control law for path following of the deep-sea manned submersible. 展开更多
关键词 path following deep-sea manned submersible terminal sliding mode control ROBUSTNESS
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KEY TECHNOLOGY IN INTELLIGENT CONTROL FOR SHEET METAL DEEP DRAWING
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作者 罗亚军 赵军 +1 位作者 何丹农 张永清 《Journal of Shanghai Jiaotong university(Science)》 EI 2001年第1期27-30,共4页
Intellectualization of sheet metal in deep drawing is a new combined technology, which is concerned with control science and computer science and sheet metal forming theory. The intelligent control system for sheet me... Intellectualization of sheet metal in deep drawing is a new combined technology, which is concerned with control science and computer science and sheet metal forming theory. The intelligent control system for sheet metal deep drawing consists of four fundamental factors: real time measurement, identification, prediction and control. Real time identification of material properties and friction coefficient is the most important factor in the whole system. An artificial neural network model for identification of the material properties and friction coefficient was established according to deep drawing characteristics and more automation. The identification of the material properties and friction coefficient was realized. 展开更多
关键词 sheet metal forming intelligent control deep drawing neural network real time identification
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Mechanism and practice of rock control in deep large span cut holes 被引量:2
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作者 Li Chong Xu Jinhai +2 位作者 Fu Chunsheng Wu Rui Ma Qianqian 《Mining Science and Technology》 EI CAS 2011年第6期891-896,共6页
Deep large span cut holes are difficult to stabilize. The 7801 cut hole in the Lu'an Wuyang Mine was used as this project's background. The main factors affecting large span cut hole stability are analyzed. Pr... Deep large span cut holes are difficult to stabilize. The 7801 cut hole in the Lu'an Wuyang Mine was used as this project's background. The main factors affecting large span cut hole stability are analyzed. Pre- stressed bolting theory was used to design a roof control method for a large span roadway. By reducing the span and applying equal strength coordinated supports the rock could be stabilized. The control prin- ciples and methods are given herein along with the analysis. A double micro arch cross section roadway is defined and its use in solving the current problem is described. Beam arch theory was used to build a model of the double micro arch cross section roadway. A support reverse force model for the arch foot intersection was also derived. A support method based upon reducing the width of the large span in the cut hole is presented. These results show that the reduced span of the roadway roof plus the use of cable anchors and single supports gives an effective way to control the large span cut hole. On site monitoring showed that the reduced span support from the double micro arch cross section roadway design had a significant effect. The roadway surface displacement was small and harmful deformation of the cut hole was effectively controlled. This will ensure its long term stability. 展开更多
关键词 deep large span cut hole Double micro arch cross-section roadway Roof control by cross cut Equal strength coordinated support
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Deformation Control of Deep Excavation Pit and Numerical Simulation with Finite Element Method
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作者 Li Yun’an Engineering Faculty, China University of Geosciences, Wuhan 430074 School of Civil Engineering and Mechanics, Shanghai Jiaotong University, Shanghai 200030 Ge Xiurun School of Civil Engineering and Mechanics, Shanghai Jiaotong University, Shanghai 200030 Tang Huiming Engineering Faculty, China University of Geosciences, Wuhan 430074 《Journal of China University of Geosciences》 SCIE CSCD 2002年第3期278-288,共11页
The authors firstly introduce deformation control of deep excavation pit indetail, and then put forward new conceptions such as: effective coefficient of excavation pit,effective area, ineffective area and critical li... The authors firstly introduce deformation control of deep excavation pit indetail, and then put forward new conceptions such as: effective coefficient of excavation pit,effective area, ineffective area and critical line, and also put forward the referential criteria ofdeformation control. The System of Optimization Design with Deformation Control of Deep ExcavationPit and Numerical Simulation with Finite Element Method (SDCDEFEM) is also briefly introduced.Factors influencing deformation of excavation pit are analyzed by the system. The measured andsimulated data of maximum deformations (settlement, displacement and upheaval) and their positionsare analyzed and discussed. The statistic formula estimating maximum deformations and theirpositions was gained, and economical-effective measures of deformation control were brought forward. 展开更多
关键词 deep excavation pit deformation control finite element effectivecoefficient of excavation pit
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基于深度强化学习的住宅区电动汽车充电策略 被引量:1
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作者 王保义 祝郑凌 张少敏 《电力科学与工程》 2024年第6期19-27,共9页
为降低电动汽车(Electricvehicle,EV)充电成本、缓解用户里程焦虑,提出了一种基于深度强化学习算法的EV充电控制策略。首先,使用数学模型定量分析EV用户的充电成本、里程焦虑以及电池老化;然后,将EV充放电问题转化为状态转移概率未知的... 为降低电动汽车(Electricvehicle,EV)充电成本、缓解用户里程焦虑,提出了一种基于深度强化学习算法的EV充电控制策略。首先,使用数学模型定量分析EV用户的充电成本、里程焦虑以及电池老化;然后,将EV充放电问题转化为状态转移概率未知的马尔可夫决策过程,使用强化学习算法得到离散的充放电决策。与传统的基于模型预测控制算法相比,在用该策略得到充电策略时可以不依赖充电环境的精确模型以及EV用户行为等不确定性因素的预测结果。实验结果表明,应用该策略可以在满足用户充电需求的同时降低充电成本、保护电池,其控制性能相比基于模型预测控制的充电策略也更为优异。 展开更多
关键词 电动汽车 住宅区 充放电控制 深度强化学习
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塔里木盆地顺北地区顺北84X井超千米含油气重大发现及其意义 被引量:1
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作者 曹自成 云露 +7 位作者 漆立新 李海英 韩俊 耿锋 林波 陈菁萍 黄诚 毛庆言 《石油与天然气地质》 EI CAS CSCD 北大核心 2024年第2期341-356,共16页
塔里木盆地顺北中部北东向走滑断裂带长期处于油气运聚富集的优势区,顺北8号走滑断裂带实钻揭示沿断裂带发育断控缝洞型油气藏,顺北84X井纵向上沿断裂带含油气高度高达1088 m,揭示断控缝洞型油气藏含油气高度大、不受现今构造高低控制... 塔里木盆地顺北中部北东向走滑断裂带长期处于油气运聚富集的优势区,顺北8号走滑断裂带实钻揭示沿断裂带发育断控缝洞型油气藏,顺北84X井纵向上沿断裂带含油气高度高达1088 m,揭示断控缝洞型油气藏含油气高度大、不受现今构造高低控制。为查明断控缝洞型油气藏含油气高度的主控因素,立足顺北中部奥陶系碳酸盐岩油气藏的成藏地质条件和钻探成果,开展顺北84X井的储层、圈闭及成藏特征等石油地质条件分析,为深化断控缝洞型油气藏认识和向深层评价拓展提供支撑。研究表明:①走滑构造破碎是致密碳酸盐岩成储的关键,其储层发育深度不受碳酸盐岩地层埋深的控制,在近9000 m的埋深条件下仍发育断控缝洞型储集体;②上覆巨厚泥岩盖层顶封、两侧致密灰岩侧封、走滑断裂平面分段和纵向分层变形是形成断控缝洞型圈闭的关键;③油-源对比分析表明油气来自寒武系玉尔吐斯组烃源岩,证实了前期顺北中、东部“寒武多期供烃、构造破裂成储、原地垂向输导、晚期成藏为主、走滑断裂控富”的成藏模式的合理性。顺北84X井的发现揭示塔里木盆地超深层致密碳酸盐岩发育受走滑断裂控制,储层纵向深度大,油气充注足,超深层勘探潜力巨大。 展开更多
关键词 含油气高度 超深层 断控油气藏 顺北84X井 顺北地区 塔里木盆地
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结合数据驱动与物理模型的主动配电网双时间尺度电压协调优化控制 被引量:1
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作者 张剑 崔明建 何怡刚 《电工技术学报》 EI CSCD 北大核心 2024年第5期1327-1339,共13页
高比例电动汽车、分布式风电、光伏接入配电网,导致电压频繁地剧烈波动。传统调压设备与逆变器动作速度差异巨大,如何协调是难点问题。该文结合数据驱动与物理建模方法,提出一种配电网双时间尺度电压协调优化控制策略。针对短时间尺度(... 高比例电动汽车、分布式风电、光伏接入配电网,导致电压频繁地剧烈波动。传统调压设备与逆变器动作速度差异巨大,如何协调是难点问题。该文结合数据驱动与物理建模方法,提出一种配电网双时间尺度电压协调优化控制策略。针对短时间尺度(min级)电压波动,以静止无功补偿器、分布式电源无功功率为决策变量,以电压二次方偏差最小为目标函数,针对平衡与不平衡配电网,基于支路潮流方程,计及物理约束构建了二次规划模型。针对长时间尺度(h级)电压波动,以电压调节器匝比、可投切电容电抗器挡位、储能系统充放电功率为动作,当前时段配电网节点功率为状态,节点电压二次方偏差为代价,构建了马尔可夫决策过程。为克服连续-离散动作空间维数灾,提出了一种基于松弛-预报-校正的深度确定性策略梯度强化学习求解算法。最后,采用IEEE 33节点平衡与123节点不平衡配电网验证了所提出方法的有效性。 展开更多
关键词 智能配电网 电压控制 深度强化学习 二次规划 双时间尺度
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顺北超深断溶体储层典型试井曲线特征及类别
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作者 张宁 李宗宇 +2 位作者 张云 聂仁仕 李景舜 《西南石油大学学报(自然科学版)》 CAS CSCD 北大核心 2024年第4期115-122,共8页
顺北地区超深断溶体储层主要发育有裂缝及片状洞穴,采用可横向穿越缝洞储集体的水平井进行开发,其试井曲线形态特征复杂多变。依据井筒和表皮效应结束后的中期试井曲线的典型特征,将顺北地区实测试井曲线分成了3个大类。该3大类试井曲... 顺北地区超深断溶体储层主要发育有裂缝及片状洞穴,采用可横向穿越缝洞储集体的水平井进行开发,其试井曲线形态特征复杂多变。依据井筒和表皮效应结束后的中期试井曲线的典型特征,将顺北地区实测试井曲线分成了3个大类。该3大类试井曲线特征直接反映了井与缝洞储集体的不同接触关系。再根据后期的试井形态特征,将顺北地区实测试井曲线细分成了9个亚类,不同的亚类试井曲线特征明显不同,是井外围缝洞发育状况变化的试井曲线响应。最后,提出了与试井曲线特征相对应的3大类9个亚类的试井解释评价物理模型。本文研究成果可用于指导顺北地区的试井分析与试井研究工作,亦可为其他深层断溶体储层的试井研究提供借鉴与参考。 展开更多
关键词 顺北地区 深层油气藏 断溶体 洞穴 试井
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基于机器深度学习的小麦播种机控制系统研究 被引量:4
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作者 单绍隆 康华 《农机化研究》 北大核心 2024年第7期208-211,共4页
针对我国小麦播种机自动控制系统的可靠性及灵敏度不高的问题,基于机器深度学习对小麦播种机的控制系统进行了设计和改进。小麦播种机的主要组成包括控制系统、排种系统、监控系统、电力系统、机架和驾驶室、覆土镇压和排肥装置。为了... 针对我国小麦播种机自动控制系统的可靠性及灵敏度不高的问题,基于机器深度学习对小麦播种机的控制系统进行了设计和改进。小麦播种机的主要组成包括控制系统、排种系统、监控系统、电力系统、机架和驾驶室、覆土镇压和排肥装置。为了使播种机的控制系统能有效进行图像检测识别,提升播种机的控制精度,采用机器深度学习中的卷积神经网络算法对控制系统进行设计,并采用迁移学习的方式对模型进行训练和检测。为了验证播种机控制系统的性能,对其进行播种精度控制和播种性能测试试验,结果表明:播种机的精度和性能均符合播种机的设计要求。 展开更多
关键词 小麦播种机 自动控制系统 机器深度学习 卷积神经网络算法 迁移学习
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海上高温高盐油藏层内沉淀深部调驱体系研究与应用
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作者 郑玉飞 朱彤宇 +3 位作者 宫汝祥 李翔 覃庆波 柏溢 《盐科学与化工》 CAS 2024年第4期50-54,共5页
针对常规调驱体系因注入困难、耐温抗盐性差及价格昂贵,难以满足海上高温高盐油藏深部调驱需求的问题,研发出一种以Na_(2)SiO_(3)为主剂的层内沉淀深部调驱体系。通过化学分析、仪器检测和物理模拟等多种方法对体系进行了配方优化和性... 针对常规调驱体系因注入困难、耐温抗盐性差及价格昂贵,难以满足海上高温高盐油藏深部调驱需求的问题,研发出一种以Na_(2)SiO_(3)为主剂的层内沉淀深部调驱体系。通过化学分析、仪器检测和物理模拟等多种方法对体系进行了配方优化和性能评价。实验研究结果表明:调驱体系的最佳母液配方组成为7%硅酸钠+30%沉淀控制剂A+1.0%沉淀控制剂B,该配方可与现场注入水中的成垢离子反应生成粒径为67.0~123.1 nm的颗粒,在向地层深部运移过程中由小到大逐渐聚并成粒径为42.6~47.4μm的无机沉淀,封堵水窜通道最终实现深部液流转向。该调驱体系耐温150℃,在50~500 mD岩心均具有良好的注入性,沉淀后封堵率可达95.9%,对于渗透率级差为8~20的双岩心提高采收率幅度可达11.0%~16.4%。矿场试验表明,层内沉淀调驱体系注入性好、工艺简单,稳油控水效果显著,W油田A井组实施措施后日增油超25 m^(3),含水率平均下降13.3%,累计增油达到7675 m^(3)。技术对于海上高温高盐油田开发具有良好的示范作用。 展开更多
关键词 层内沉淀 高温高盐 性能评价 深部调驱 矿场试验
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减氮和侧深基施缓混肥对‘南粳5055’产量、品质及氮素吸收利用的影响
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作者 阚建鸾 石吕 +4 位作者 韩笑 周志宏 苏建平 刘建 薛亚光 《中国农学通报》 2024年第2期91-96,共6页
旨在探讨减氮和侧深基施缓混肥对水稻产量、品质和氮素吸收利用的影响,本研究以当地主推粳稻‘南粳5055’为材料,设置不施氮肥(0N)、当地常规施肥(CK)、一次性侧深基施缓混肥(S1)、侧深基施缓混肥+追施速效氮肥(S2) 4个处理,分别在如皋... 旨在探讨减氮和侧深基施缓混肥对水稻产量、品质和氮素吸收利用的影响,本研究以当地主推粳稻‘南粳5055’为材料,设置不施氮肥(0N)、当地常规施肥(CK)、一次性侧深基施缓混肥(S1)、侧深基施缓混肥+追施速效氮肥(S2) 4个处理,分别在如皋市东陈镇和白蒲镇两地的水稻田开展试验。两地的试验结果均表明:与CK相比,在减氮25%情况下,S1和S2均明显改善了稻米的外观品质和蒸煮食味品质,但两者的水稻产量和总吸氮量均有所降低,平均分别减少了5.12%、1.27%和9.53%、2.77%。其中S1明显减产主要由于每穗粒数的显著降低,而S2则与CK无显著差异。另外,S2也较CK显著提高了氮肥的吸收利用率、农学效率和偏生产力。表明在氮肥大幅减少的情况下,采用侧深基施缓混肥+追施速效氮肥更有利于实现水稻的绿色优质高效生产。 展开更多
关键词 水稻 减氮 侧深施缓混肥 产量 品质
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水电工程深厚覆盖层地基防渗设计与潜蚀问题
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作者 孙保平 刘超 +2 位作者 金伟 李帅 王刚 《水力发电》 CAS 2024年第6期49-54,共6页
我国西部一些水电站的坝址存在超深厚覆盖层,给工程的渗流控制和设计带来巨大的困难。垂直防渗墙是深厚覆盖层地基渗流控制最常用的措施。通过回顾泸定水电站深厚覆盖层悬挂式防渗墙地基异常渗漏治理的案例,指出对于西部河流中广泛存在... 我国西部一些水电站的坝址存在超深厚覆盖层,给工程的渗流控制和设计带来巨大的困难。垂直防渗墙是深厚覆盖层地基渗流控制最常用的措施。通过回顾泸定水电站深厚覆盖层悬挂式防渗墙地基异常渗漏治理的案例,指出对于西部河流中广泛存在的不稳定砂砾石地层,在关注渗流出口保护的同时,还应重视地基内部高流速和高水力梯度区域的潜蚀风险。为定量评价砂砾石地基内部潜蚀及其导致的后果,应开展深厚覆盖层内部稳定性评价准则、高上覆压力下砂砾石潜蚀试验技术、潜蚀数值模拟方法及潜蚀本构模型等关键技术问题的研究。 展开更多
关键词 深厚覆盖层 防渗 潜蚀 渗透破坏 水电工程
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基于深度强化学习的电-气区域综合能源系统安全校正控制决策方法
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作者 彭寒梅 胡磊 +2 位作者 谭貌 李金果 苏永新 《电网技术》 EI CSCD 北大核心 2024年第3期1019-1029,共11页
电–气区域综合能源系统电、气相互耦合与影响,使得其安全校正控制难度大且对快速性要求高,为此,提出一种基于深度确定性策略梯度(deepdeterministicpolicy gradient,DDPG)算法的安全校正控制决策方法。首先,进行系统多能流与变量分析,... 电–气区域综合能源系统电、气相互耦合与影响,使得其安全校正控制难度大且对快速性要求高,为此,提出一种基于深度确定性策略梯度(deepdeterministicpolicy gradient,DDPG)算法的安全校正控制决策方法。首先,进行系统多能流与变量分析,建立安全校正控制的目标与约束条件。然后,构建基于DDPG的安全校正控制模型,设计目标奖励和各种约束条件奖励,提出结合基于综合灵敏度的安全校正知识经验设计目标奖励函数,使调整具有方向性,且目标奖励考虑能量枢纽(energy hub,EH)的经济效益及其可再生能源消纳;通过智能体离线训练,使其能够在线做出实时最优的安全校正控制策略,预先产生专家经验数据集存放于经验回放池,提高训练速度和收敛性。最后,通过含EH电–气区域综合能源系统仿真算例验证了所提方法的有效性。 展开更多
关键词 电–气区域综合能源系统 安全校正控制 深度强化学习 综合灵敏度 能量枢纽
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