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Mellin Transform-Based Correction Method for Linear Scale Inconsistency of Intrusion Events Identification in OFPS
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作者 Baocheng WANG Dandan QU +1 位作者 Qing TIAN Liping PANG 《Photonic Sensors》 SCIE EI CAS CSCD 2018年第3期220-227,共8页
For the problem that the linear scale of intrusion signals in the optical fiber pre-warning system (OFPS) is inconsistent, this paper presents a method to correct the scale. Firstly, the intrusion signals are interc... For the problem that the linear scale of intrusion signals in the optical fiber pre-warning system (OFPS) is inconsistent, this paper presents a method to correct the scale. Firstly, the intrusion signals are intercepted, and an aggregate of the segments with equal length is obtained. Then, the Mellin transform (MT) is applied to convert them into the same scale. The spectral characteristics are obtained by the Fourier transform. Finally, we adopt back-propagation (BP) neural network to identify intrusion types, which takes the spectral characteristics as input. We carried out the field experiments and collected the optical fiber intrusion signals which contain the picking signal, shoveling signal, and running signal. The experimental results show that the proposed algorithm can effectively improve the recognition accuracy of the intrusion signals. 展开更多
关键词 linear scale OFPS MT BP neural network spectral characteristics
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High-efciency improved symmetric successive over-relaxation preconditioned conjugate gradient method for solving large-scale finite element linear equations 被引量:1
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作者 李根 唐春安 李连崇 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2013年第10期1225-1236,共12页
Fast solving large-scale linear equations in the finite element analysis is a classical subject in computational mechanics. It is a key technique in computer aided engineering (CAE) and computer aided manufacturing ... Fast solving large-scale linear equations in the finite element analysis is a classical subject in computational mechanics. It is a key technique in computer aided engineering (CAE) and computer aided manufacturing (CAM). This paper presents a high-efficiency improved symmetric successive over-relaxation (ISSOR) preconditioned conjugate gradient (PCG) method, which maintains lelism consistent with the original form. Ideally, the by 50% as compared with the original algorithm. the convergence and inherent paralcomputation can It is suitable for be reduced nearly high-performance computing with its inherent basic high-efficiency operations. By comparing with the numerical results, it is shown that the proposed method has the best performance. 展开更多
关键词 improved preconditioned conjugate gradient (PCG) method conjugate gradient method large-scale linear equation finite element method
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A Modification of the Relative Weightings of Symptoms Utilizing a Logistic Function to Enhance the Linearity of the Brief Psychiatric Rating Scale: A Retrospective Analysis
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作者 Jitsuki Sawamura Shigeru Morishita Jun Ishigooka 《Journal of Behavioral and Brain Science》 2012年第2期225-238,共14页
Introduction: Although the Brief Psychiatric Rating Scale (BPRS) is widely used for evaluating patients with schizophrenia, the meaning of the weights of the individual symptoms is ambiguous. The aims of the study wer... Introduction: Although the Brief Psychiatric Rating Scale (BPRS) is widely used for evaluating patients with schizophrenia, the meaning of the weights of the individual symptoms is ambiguous. The aims of the study were 1) to investigate whether the modification of relative weights of items of the BPRS is able to enhance its correlation with the Clinical Global Impression-Schizophrenia scale (CGI-SCH) and 2) to construct a potential modified BPRS. Methods: We evaluated 200 schizophrenia patients using the BPRS and the CGI-SCH and drew the scatter plot distributions of the two scales. Next, univariate regression for the CGI-SCH using individual symptoms of the BPRS was performed. Multivariate regression utilizing the ‘logistic function’ was then conducted to allocate marks to each item and Pearson’s r correlation coefficient and r-squared between the two scales were assessed. After that, we constructed an example of a potential modified BPRS. Results: With the scatter plot for the two scales, a logarithmic curve was obtained;this was described by [CGI-SCH] = 3.2248 × ln[18-item BPRS] – 7.2044 (p i” that could express the relative weights of individual symptoms. Subsequently, modification of point allocations according to “Pi” yielded a Pearson’s r of 0.8491 and an r-squared of 0.7718 (not changed) (both p < 0.001). An example of a potential modified BPRS was constructed. Conclusions: Within the limits of our data, the weightings of items of the BPRS improved the correlation of the BPRS with the CGI-SCH for evaluating schizophrenia. 展开更多
关键词 Evaluation scale linearITY Weightings MODIFICATION BPRS SCHIZOPHRENIA
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DECENTRALIZED STABILIZATION OF LARGE-SCALE LINEAR INTERCONNECTED SYSTEMS WITH TIME-VARYING DELAYS
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作者 余昭旭 孙继涛 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2000年第9期1053-1057,共5页
The decentralized stabilization conditions for large-scale linear interconnection systems with time-varying delays were established by using some different decomposition cases of interconnection matrices, and a method... The decentralized stabilization conditions for large-scale linear interconnection systems with time-varying delays were established by using some different decomposition cases of interconnection matrices, and a method for designing the decentralized local memoryless state feedback controllers was proposed. All of the considered delays are continuous function, and satisfy some conditions. 展开更多
关键词 large-scale systems linear interconnection systems time-varying delay decentralized stabilization
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Combining Methods of Lyapunov for Exponential Stability of Linear Dynamic Systems on Time Scales
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作者 Nguyen Ngoc Huy Dang Dinh Chau 《Applied Mathematics》 2014年第21期3452-3459,共8页
Consider the linear dynamic equation on time scales (1) where , ,?is a rd-continuous function, T is a time scales. In this paper, we shall investigate some results for the exponential stability of the dynamic Equation... Consider the linear dynamic equation on time scales (1) where , ,?is a rd-continuous function, T is a time scales. In this paper, we shall investigate some results for the exponential stability of the dynamic Equation (1) by combinating the first approximate method and the second method of Lyapunov. 展开更多
关键词 Time scales EXPONENTIAL Stability linear Dynamic EQUATION
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Analysis of the Invariance and Generalizability of Multiple Linear Regression Model Results Obtained from Maslach Burnout Scale through Jackknife Method
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作者 Tolga Zaman Kamil Alakus 《Open Journal of Statistics》 2015年第7期645-651,共7页
The purpose of this study was to examine the burnout levels of research assistants in Ondokuz Mayis University and to examine the results of multiple linear regression model based on the results obtained from Maslach ... The purpose of this study was to examine the burnout levels of research assistants in Ondokuz Mayis University and to examine the results of multiple linear regression model based on the results obtained from Maslach Burnout Scale with Jackknife Method in terms of validity and generalizability. To do this, a questionnaire was given to 11 research assistants working at Ondokuz Mayis University and the burnout scores of this questionnaire were taken as the dependent variable of the multiple linear regression model. The variable of burnout was explained with the variables of age, weekly hours of classes taught, monthly average credit card debt, numbers of published articles and reports, gender, marital status, number of children and the departments of the research assistants. Dummy variables were assigned to the variables of gender, marital status, number of children and the departments of the research assistants and thus, they were made quantitative. The significance of the model as a result of multiple linear regressions was examined through backward elimination method. After this, for the five explanatory variables which influenced the variable of burnout, standardized model coefficients and coefficients of determination, and 95% confidence intervals of these values were estimated through Jackknife Method and the generalizability of the parameter estimation results of these variables on population was researched. 展开更多
关键词 JACKKNIFE METHOD INVARIANCE GENERALIZABILITY Maslach BURNOUT scale Multiple linear Regression Backward Elimination METHOD
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Robust non-fragile control for discrete-delay nonlinear large-scale systems
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作者 吴忠强 李卓 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2010年第4期481-485,共5页
Time-delays,due to the information transmission between subsystems,naturally exist in large-scale systems and the existence of the delay is frequently a source of instability. This paper considers the problems of robu... Time-delays,due to the information transmission between subsystems,naturally exist in large-scale systems and the existence of the delay is frequently a source of instability. This paper considers the problems of robust non-fragile fuzzy control for a class of uncertain discrete nonlinear large-scale systems with time-delay and controller gain perturbations described by T-S fuzzy model. An equivalent T-S fuzzy model is represented for discrete-delay nonlinear large-scale systems. A sufficient condition for the existence of such non-fragile controllers is further derived via the Lyapunov function and the linear matrix inequality( LMI) approach. Simulation results demonstrate the feasibility and the effectiveness of the proposed design and the proper stabilization of the system in spite of controller gain variations and uncertainties. 展开更多
关键词 non-fragile control discrete-delay nonlinear large-scale systems T-S fuzzy model linear matrix inequality
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Scale, Complexity, and Cybersecurity Risk Management
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作者 Christopher Briscoe Carl Young 《Journal of Information Security》 2024年第4期524-544,共21页
Elementary information theory is used to model cybersecurity complexity, where the model assumes that security risk management is a binomial stochastic process. Complexity is shown to increase exponentially with the n... Elementary information theory is used to model cybersecurity complexity, where the model assumes that security risk management is a binomial stochastic process. Complexity is shown to increase exponentially with the number of vulnerabilities in combination with security risk management entropy. However, vulnerabilities can be either local or non-local, where the former is confined to networked elements and the latter results from interactions between elements. Furthermore, interactions involve multiple methods of communication, where each method can contain vulnerabilities specific to that method. Importantly, the number of possible interactions scales quadratically with the number of elements in standard network topologies. Minimizing these interactions can significantly reduce the number of vulnerabilities and the accompanying complexity. Two network configurations that yield sub-quadratic and linear scaling relations are presented. 展开更多
关键词 COMPLEXITY CYBERSECURITY scale Scaling Relations Stochastic linear Non-linear MACROSCOPIC Organized Complexity Disorganized Complexity
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序列缩放攻击下多智能体系统的二分一致性
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作者 王正新 陶怡梅 +1 位作者 蒋国平 冯元珍 《南京邮电大学学报(自然科学版)》 北大核心 2025年第5期94-101,共8页
研究基于观测器的序列缩放攻击下线性多智能体系统的二分一致性。首先,考虑到序列缩放攻击的攻击程度未知,设计了观测器来估计智能体的真实状态,以减少对误差系统稳定性的影响。其次,攻击信号被注入到整个网络的所有控制器到执行器的通... 研究基于观测器的序列缩放攻击下线性多智能体系统的二分一致性。首先,考虑到序列缩放攻击的攻击程度未知,设计了观测器来估计智能体的真实状态,以减少对误差系统稳定性的影响。其次,攻击信号被注入到整个网络的所有控制器到执行器的通道中,针对线性多智能体系统,提出基于观测器估计状态的分布式控制器,可以有效避免使用系统本身的信息。最后,利用Ly‑apunov函数证明受序列缩放攻击的线性多智能体系统在所设计的控制器下可以实现二分一致性,通过数值仿真验证理论结果的有效性。 展开更多
关键词 线性多智能体系统 序列缩放攻击 分布式控制 二分一致性
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基于源荷空间匹配关系分析的电力系统异速生长规律初探 被引量:1
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作者 林子惠 武志刚 刘彦伶 《电力系统及其自动化学报》 北大核心 2025年第1期120-130,共11页
为深入探索电力系统规模增长的规律,揭示电力系统源荷空间匹配关系驱动其发展演化的本质机理,本文进行了电力系统发展演化的异速生长规律研究。首先,引入生物领域中的异速生长概念,基于电能运输网络模型推导出电力系统规模发展在理论上... 为深入探索电力系统规模增长的规律,揭示电力系统源荷空间匹配关系驱动其发展演化的本质机理,本文进行了电力系统发展演化的异速生长规律研究。首先,引入生物领域中的异速生长概念,基于电能运输网络模型推导出电力系统规模发展在理论上满足异速生长的规律,其尺度因子为3/4,呈亚线性增长模式。然后,从涌现视角出发,构造考虑距离和电网供电余量的优选因子,基于局域世界演化模型设计一种满足全空间尺度电力电量平衡的基本要求的电力系统空间演化零阶模型。最后,通过多主体仿真验证了单源电力系统和多源电力系统规模增长均满足异速生长规律的理论推导。 展开更多
关键词 电力系统空间演化 异速生长 复杂网络 亚线性增长 尺度因子
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基于脑电-眼动的乡村线状空间感知效能研究 被引量:1
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作者 任洪国 李振宇 +1 位作者 刘颖 邵惠彬 《河北工程大学学报(自然科学版)》 2025年第3期97-105,共9页
为客观评估乡村线状公共空间改造对使用者生理与情感的影响,结合脑电图、眼动追踪技术及感知恢复量表,量化分析了36名被试者在主街道、巷道、小径及河流场景改造前后的生理舒适度、视觉关注度及主观情感响应。结果显示,改造后的乡村线... 为客观评估乡村线状公共空间改造对使用者生理与情感的影响,结合脑电图、眼动追踪技术及感知恢复量表,量化分析了36名被试者在主街道、巷道、小径及河流场景改造前后的生理舒适度、视觉关注度及主观情感响应。结果显示,改造后的乡村线状公共空间使被试者的顶叶和枕叶区域的脑电活动显著增强,双侧瞳孔直径平均扩大4.02%,视觉驻留时间延长4.01%,感知恢复量表评分在远离性、魅力性、延展性以及兼容性维度均显著提升。研究表明,通过文化符号传承、生态设计及人本化优化,乡村线状公共空间的感知效能与环境品质显著提升。本研究创新性地融合多模态生理数据与主观评价,为乡村公共空间设计提供了科学化、循证化的决策依据。 展开更多
关键词 脑电图 眼动追踪技术 感知恢复量表 线状公共空间
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基于小尺度滚刀直线切割试验的岩石强度预测
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作者 耿麒 李晓斌 +4 位作者 黄雨枫 汪学斌 杨沐霖 郭惠川 章慧健 《山东大学学报(工学版)》 北大核心 2025年第3期111-120,共10页
为支撑岩土、隧道工程中的岩石选样及现场施工的岩石强度测试,研究利用小尺度滚刀直线切割试验反推岩石强度。从隧道工程现场和岩石矿场采集单轴抗压强度为50~230 MPa的岩石试样共9批次,制备棒状和块状试样并分别开展单轴压缩、巴西劈... 为支撑岩土、隧道工程中的岩石选样及现场施工的岩石强度测试,研究利用小尺度滚刀直线切割试验反推岩石强度。从隧道工程现场和岩石矿场采集单轴抗压强度为50~230 MPa的岩石试样共9批次,制备棒状和块状试样并分别开展单轴压缩、巴西劈裂和小尺度滚刀直线切割试验;选取其中7批次试验数据,分别得到单轴抗压强度、劈裂抗拉强度与直线切割试验的法向力均值、峰值及峰均值的拟合函数,用剩余2批次试验结果验证所得预测模型的准确性。结果表明:岩石单轴抗压强度与法向载荷的拟合相关系数大于0.9,劈裂抗拉强度与法向载荷的拟合相关系数大于0.8,说明岩石强度与切割载荷成强线性相关性;验证试验发现,利用法向力均值、峰均值验证时,岩石单轴抗压强度的预测值与试验值误差小于5%,劈裂抗拉强度的预测值与试验值误差小于10%,说明所建模型具有较高的准确性。使用本研究所提出的试验方法及所建模型,可以快速准确地预估岩石试样的强度,为室内试验时岩石采样和现场施工时岩石强度评估提供了一种有效的手段。 展开更多
关键词 滚刀破岩 岩石强度 直线切割试验 缩尺试验 预测模型
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基于负刚度吸振器的轧机辊系非线性垂振控制
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作者 段子衡 和东平 +1 位作者 徐慧东 王涛 《振动与冲击》 北大核心 2025年第7期96-106,共11页
轧机振动理论的研究一直是轧制成形领域的关键科学问题,对提高板材的质量以及设备的稳定性至关重要。为了对轧机辊系的非线性垂振现象进行合理的控制,设计了一种安装于上平衡梁处的负刚度吸振器,并建立了安装吸振器的轧机辊系非线性垂... 轧机振动理论的研究一直是轧制成形领域的关键科学问题,对提高板材的质量以及设备的稳定性至关重要。为了对轧机辊系的非线性垂振现象进行合理的控制,设计了一种安装于上平衡梁处的负刚度吸振器,并建立了安装吸振器的轧机辊系非线性垂直振动模型。运用多尺度法求解得到了轧机辊系的主共振幅频特性方程,分析了轧制力、负刚度和阻尼的动态变化对系统幅频特性的影响,通过仿真分析了轧辊与负刚度吸振器相互作用的时域特性、频谱特性、幅频特性以及功率流特性。基于功率流理论并结合有限元仿真证明了模型建立的正确性以及负刚度吸振器的可行性,通过对比发现负刚度吸振器对于轧机非线性垂振有着良好的控制效果,为轧机非线性动力学分析及稳定性控制提供理论指导和技术支持。 展开更多
关键词 轧机 负刚度吸振器 非线性 多尺度法 功率流
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工作用玻璃线纹尺校准方法及应用研究 被引量:1
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作者 刘靖 《仪器仪表用户》 2025年第8期84-86,共3页
本文着重对工作用玻璃线纹尺的校准方法开展深入研究。工作用玻璃线纹尺常作为光学设备的配套自校工具,然而当前的溯源体系存在诸多不足,本文依据长度测量的基本原理,精心挑选激光干涉仪以及符合精度要求的影像测量仪等,构建起完整的校... 本文着重对工作用玻璃线纹尺的校准方法开展深入研究。工作用玻璃线纹尺常作为光学设备的配套自校工具,然而当前的溯源体系存在诸多不足,本文依据长度测量的基本原理,精心挑选激光干涉仪以及符合精度要求的影像测量仪等,构建起完整的校准测量装置系统。通过校准实验,对多种规格的玻璃线纹尺进行测量,并充分考虑环境因素,实施温度和湿度补偿。本文搭建了适用于低精度等级线纹尺的校准系统,切实解决了溯源难题,为完善计量检定系统提供了有价值的参考。 展开更多
关键词 玻璃线纹尺 校准手段 不确定度评估
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中性锌空气电池催化剂的理论设计
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作者 孙中贤 张宝 孙威 《硅酸盐学报》 北大核心 2025年第7期1816-1821,共6页
中性锌空气电池因其高比能、高安全性和长寿命受到广泛关注,但其空气正极动力学迟滞问题限制了其实际应用。通过第一性原理计算方法,研究了中性锌空气电池的催化路径,并提出了其催化剂设计的描述符。结果表明:4电子路径倾向于发生在氧... 中性锌空气电池因其高比能、高安全性和长寿命受到广泛关注,但其空气正极动力学迟滞问题限制了其实际应用。通过第一性原理计算方法,研究了中性锌空气电池的催化路径,并提出了其催化剂设计的描述符。结果表明:4电子路径倾向于发生在氧吸附强度较强的催化剂上,而2电子路径更易出现在吸附强度较弱的催化剂表面。此外,吸附强度与过电势遵循Sabatier原理,适中吸附强度具有最佳性能。研究发现Pt和Ag表现出适中的氧吸附特性,是中性锌空气电池正极催化剂的潜在候选材料。 展开更多
关键词 中性锌空气电池 催化剂 描述符 第一性原理计算 线性标度关系
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SUS436L冷板表面线状缺陷分析和工艺改进
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作者 李鹏飞 翟俊 +1 位作者 李宏 赵嘉伦 《山西冶金》 2025年第4期171-172,213,共3页
通过对SUS436L超纯铁素体不锈钢冷板表面常见等间隔纵向线状缺陷微观分析和中试轧制试验,明确了热轧过程残留氧化铁鳞在轧制后压入基体是导致线状缺陷的主要原因。该缺陷呈现规律性间隔,主要与铸坯修磨磨痕有关,通过调整加热炉加热温度... 通过对SUS436L超纯铁素体不锈钢冷板表面常见等间隔纵向线状缺陷微观分析和中试轧制试验,明确了热轧过程残留氧化铁鳞在轧制后压入基体是导致线状缺陷的主要原因。该缺陷呈现规律性间隔,主要与铸坯修磨磨痕有关,通过调整加热炉加热温度和优化铸坯修磨工艺可明显改善此类缺陷。 展开更多
关键词 修磨 超纯铁素体不锈钢 线状缺陷 氧化铁鳞
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乡镇尺度SDGSAT-1微光影像灯光分布与不透水层的相关性分析
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作者 王昭 闫冬梅 +1 位作者 唐娉 张正 《中国科学院大学学报(中英文)》 北大核心 2025年第4期528-537,共10页
以安徽省亳州市为研究区域,通过可视化方式展现了几种不同用途建筑灯光在2个时相的强度差别,继而对灯光面积和不透水层面积进行线性回归分析和交并比分析,获得城市与乡镇地区灯光分布的差异及变化情况。结果显示:1)不同建筑类型在不同... 以安徽省亳州市为研究区域,通过可视化方式展现了几种不同用途建筑灯光在2个时相的强度差别,继而对灯光面积和不透水层面积进行线性回归分析和交并比分析,获得城市与乡镇地区灯光分布的差异及变化情况。结果显示:1)不同建筑类型在不同时间的灯光强度存在差异;2)因空间分辨率高,SDGSAT-1微光影像能够部分区分城市区域的主干道路灯光与建筑灯光,城市区域的灯光大部分由道路发出;3)灯光面积与不透水层面积的线性回归在城市区域能够产生较好的拟合效果,乡镇地区的灯光面积因不易被传感器接收而难以与不透水层面积建立良好的拟合关系;4)亳州市各街道、乡镇灯光面积与不透水层面积的交并比与GDP相关。 展开更多
关键词 SDGSAT-1 微光影像 乡镇尺度 线性回归 交并比
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小口径岩心钻探冲洗液流量计研制与应用
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作者 洪毅 万宇航 +5 位作者 宋永朋 张所邦 赵子栋 李永超 肖雨 陈敏 《钻探工程》 2025年第S1期171-177,共7页
小口径岩心钻探过程中,冲洗液流量监测困难。为了实时精确监测冲洗液流量,及时发现钻进过程中异常流量变化并进行调节和处理,确保钻头安全钻进,防止烧钻和埋钻等孔内事故发生,创新性地设计了一种基于浮子流量计基本结构、结合磁传导技... 小口径岩心钻探过程中,冲洗液流量监测困难。为了实时精确监测冲洗液流量,及时发现钻进过程中异常流量变化并进行调节和处理,确保钻头安全钻进,防止烧钻和埋钻等孔内事故发生,创新性地设计了一种基于浮子流量计基本结构、结合磁传导技术、可精确测量小口径冲洗液流量的流量计。分别设计了直线与环状刻度两种流量示数方案,并对直线刻度磁传导错位进行了试验,同时对浮子、锥管等主要零部件进行了参数优选试验。试验结果表明:采用8颗磁体时,主被动磁铁无错位现象;浮子直径33.8 mm、锥管两端直径52/34 mm的流量检测数据趋于线性,更适应实际需要。钻探现场应用情况表明:该冲洗液流量计具有良好的精度、灵敏度、适应性和可靠性,可实现孔内冲洗液流量的实时监测,减少孔内事故发生。 展开更多
关键词 冲洗液流量计 浮子流量计 磁传导 直线刻度 环状刻度
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