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Effects of Management Practices on Agronomic Parameters in Cocoa Agroecosystems at Peripheral Zone of Ebo Forest Reserve, Littoral Region, Cameroon
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作者 Ofundem Tataw Ojong Enow Andrew Egbe +2 位作者 Joseph-Marie Ondoua Tina Fongod Raymond Ndip Nkongho 《Agricultural Sciences》 CAS 2022年第10期1151-1175,共25页
The study was carried out to assess the effect of management practices on agronomic parameters of cocoa agroecosystems in the peripheral zone of Ebo Forest Reserve. Purposive random sampling was conducted to establish... The study was carried out to assess the effect of management practices on agronomic parameters of cocoa agroecosystems in the peripheral zone of Ebo Forest Reserve. Purposive random sampling was conducted to establish experimental plots on the farms of willing farmers. Demonstration plots were established and agronomic parameters were monitored for “farmers’ practice (FP) and integrated crop pest and disease management (ICPM) practice” using indicators of Cocoa agro-ecosystem analysis (AESA). The FP and ICPM treatments were replicated in ten sites. From AESA records of agronomic parameters, the “observe, learn, decide and act” (OLDA) model was implemented in the ICPM treatments only. The effects of management practices were analyzed using a two-way analysis of variance (ANOVA), and treatment means compared using Turkey’s T-test at 5% probability. Results of ANOVA between the two Management practices showed that over 50% of the response variables were statistically significant. Means separated through GLM ANOVA with Tukey pairwise comparisons at α = 0.05 showed that 14 (53.8%) out of 26 response variables monitored were statistically significant between the two management practices. Pruning, shade management, phytosanitary harvest, rational use of pesticides, farm sanitation, pod harvesting, breaking, fermentation of beans and drying were regular in the ICPM treatment and time-bound in the FP treatment. The average total production varied from 385.83 kg/ha in FP treatment to 572.8 kg/ha in the ICPM treatment, still below the average standard of 1000 kg/ha. The OLDA model applied in ICPM treatment following AESA is a relevant tool to enhance sustainability in the management of cocoa agroecosystems. Farmers should be sensitized and trained on appropriate farm management techniques and enhance access to extension services as well as make available improved and grafted planting materials to ensure appropriate productivity levels. 展开更多
关键词 AGROECOSYSTEM Agronomic parameters Cocoa management Practices
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A Novel PF-LSSVR-based Framework for Failure Prognosis of Nonlinear Systems with Time-varying Parameters 被引量:5
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作者 CHEN Xiongzi YU Jinsong +1 位作者 TANG Diyin WANG Yingxun 《Chinese Journal of Aeronautics》 SCIE EI CSCD 2012年第5期715-724,共10页
Particle filtering (PF) is being applied successfully in nonlinear and/or non-Gaussian system failure prognosis. However, for failure prediction of many complex systems whose dynamic state evolution models involve t... Particle filtering (PF) is being applied successfully in nonlinear and/or non-Gaussian system failure prognosis. However, for failure prediction of many complex systems whose dynamic state evolution models involve time-varying parameters, the tradi- tional PF-based prognosis framework will probably generate serious deviations in results since it implements prediction through iterative calculation using the state models. To address the problem, this paper develops a novel integrated PF-LSSVR frame- work based on PF and least squares support vector regression (LSSVR) for nonlinear system failure prognosis. This approach employs LSSVR for long-term observation series prediction and applies PF-based dual estimation to collaboratively estimate the values of system states and parameters of the corresponding future time instances. Meantime, the propagation of prediction un- certainty is emphatically taken into account. Therefore, PF-LSSVR avoids over-dependency on system state models in prediction phase. With a two-sided failure definition, the probability distribution of system remaining useful life (RUL) is accessed and the corresponding methods of calculating performance evaluation metrics are put forward. The PF-LSSVR framework is applied to a three-vessel water tank system failure prognosis and it has much higher prediction accuracy and confidence level than traditional PF-based framework. 展开更多
关键词 prognostics and health management nonlinear systems failure prognosis particle filtering least squares supportvector regression time-varying parameter remaining useful life
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Local parameter identification with neural ordinary differential equations 被引量:1
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作者 Qiang YIN Juntong CAI +1 位作者 Xue GONG Qian DING 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2022年第12期1887-1900,共14页
The data-driven methods extract the feature information from data to build system models, which enable estimation and identification of the systems and can be utilized for prognosis and health management(PHM). However... The data-driven methods extract the feature information from data to build system models, which enable estimation and identification of the systems and can be utilized for prognosis and health management(PHM). However, most data-driven models are still black-box models that cannot be interpreted. In this study, we use the neural ordinary differential equations(ODEs), especially the inherent computational relationships of a system added to the loss function calculation, to approximate the governing equations. In addition, a new strategy for identifying the local parameters of the system is investigated, which can be utilized for system parameter identification and damage detection. The numerical and experimental examples presented in the paper demonstrate that the strategy has high accuracy and good local parameter identification. Moreover, the proposed method has the advantage of being interpretable. It can directly approximate the underlying governing dynamics and be a worthwhile strategy for system identification and PHM. 展开更多
关键词 neural ordinary differential equation(ODE) parameter identification prognosis and health management(PHM) system damage detection
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Impact of Capacity Parameters on Flexible Inventory Control Decision Model
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作者 WANG Yi LE Meilong 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2020年第S01期124-132,共9页
From the mathematical point of view,the flexible inventory control model is proved in the practical problem application and the rationality of the capacity parameter selection and calculation.The purpose is to activel... From the mathematical point of view,the flexible inventory control model is proved in the practical problem application and the rationality of the capacity parameter selection and calculation.The purpose is to actively respond to demand fluctuations when there is a demand forecast error or a missing part of the demand information,and to avoid the risk of passive variable demand forecasting to set the immutable inventory capacity.At the same time,the game is controlled by the flexible and variable inventory control strategy and the customer’s willingness to demand.The paper mainly studies the influence of the setting of capacity parameters on the booking-limit decision and its benefits under the control of flexible space with variable total capacity.Through the two trends of capacity increase flexibility and capacity reduction flexibility in the flexible inventory control model,the mathematical performance and marginal utility methods are introduced to change the performance of the booking-limit control decision model under different scenarios.The correlation analysis between the capacity limit level and the return under the optimal Bookinglimit decision,and the above two flexibility parameters are obtained. 展开更多
关键词 flexible inventory control capacity parameter booking-limit control decision model revenue management
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Global sensitivity analysis for choosing the main soil parameters of a crop model to be determined
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作者 Hubert Varella Samuel Buis +1 位作者 Marie Launay Martine Guérif 《Agricultural Sciences》 2012年第7期949-961,共13页
The use of a crop model like STICS for appropriate management decision support requires a good knowledge of all the parameters of the model. Among them, the soil parameters are difficult to know at each point of inter... The use of a crop model like STICS for appropriate management decision support requires a good knowledge of all the parameters of the model. Among them, the soil parameters are difficult to know at each point of interest and costly techniques may be used to measure them. It is therefore important to know which soil parameters need to be determined. It can be stated that those which affect significantly the output variable deserve an accurate determination while those which slightly affect the model output variable do not. This paper demonstrates how a global sensitivity analysis method based on variance decomposition can be applied on soil parameters in order to divide them in the two categories. The Extended FAST method applied to the crop model STICS and a set of 13 soil parameters first allows to calculate the part of variance explained by each soil parameter (giving global sensitivity indices of the soil parameters) and the coefficient of variation of the output variables (measuring the effect of the parameter uncertainty on each variable). These metrics are therefore used for deciding on the importance of the parameter value measurement. Different output variables (Leaf Area Index and chlorophyll content) are evaluated at different stages of interest while others (crop yield, grain protein content, soil mineral nitrogen) are evaluated at harvest. The analysis is applied on two different annual crops (wheat and sugar beet), two contrasted weather and two types of soil depth. When the uncertainty of the output generated by the soil parameters is large (coefficient of variation > 1/3), only the parameters having a significant global sensitivity indices (higher than 10%) are retained. The results show that the number of soil parameters which deserve an accurate determination can be significantly reduced by the use of this relevant method for appropriate management decision support. 展开更多
关键词 Global Sensitivity ANALYSIS Uncertainty ANALYSIS SOIL parameters CROP Model STICS management DECISION Support Agro-Environmental VARIABLES
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基于云平台的深度学习电池参数识别与SOH估计
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作者 张维平 王志翠 +2 位作者 姬莉 李国强 赵文蕾 《电池》 北大核心 2026年第1期46-52,共7页
锂离子电池健康状态(SOH)估计对电池管理系统(BMS)的安全可靠运行至关重要。传统的移动窗口最小二乘法在复杂动态环境下,存在精度不足和适应性差的问题。提出一种基于云计算平台的深度学习增强电池模型参数识别与SOH估计方法。该方法完... 锂离子电池健康状态(SOH)估计对电池管理系统(BMS)的安全可靠运行至关重要。传统的移动窗口最小二乘法在复杂动态环境下,存在精度不足和适应性差的问题。提出一种基于云计算平台的深度学习增强电池模型参数识别与SOH估计方法。该方法完整保留二阶RC等效电路模型的数学基础,并融合卷积神经网络-长短期记忆(LSTM)网络-注意力机制的深度学习架构,构建云端智能优化的参数识别框架。所提方法在保持移动窗口最小二乘算法理论完整性的基础上,提升SOH预测精度,平均绝对百分比误差(MAPE)从传统方法的1.15%降至0.31%。 展开更多
关键词 锂离子电池 云计算 深度学习 参数识别 健康状态(SOH)估计 电池管理系统(BMS)
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氢燃料电池混合动力汽车动力传动系统优化研究
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作者 姚永玉 周辉 韩志凯 《洛阳理工学院学报(自然科学版)》 2026年第1期51-57,共7页
随着新能源汽车技术的快速迭代,燃料电池混合动力汽车因功率密度高和零排放等优点被广泛关注。参考某品牌汽车的并联式混合驱动动力传动系统参数,基于MATLAB平台搭建了燃料电池电动汽车基于模糊控制策略的能量管理系统,利用CRUISE M搭... 随着新能源汽车技术的快速迭代,燃料电池混合动力汽车因功率密度高和零排放等优点被广泛关注。参考某品牌汽车的并联式混合驱动动力传动系统参数,基于MATLAB平台搭建了燃料电池电动汽车基于模糊控制策略的能量管理系统,利用CRUISE M搭建整车模型,实施联合仿真,实现了功率分配、锂离子蓄电池的荷电状态(State of Charge,SOC)等参数的优化匹配。和实车整车性能参数对比显示:测试模型的最高车速和百公里加速时间均提高1.3%以上,验证了控制策略的正确性。 展开更多
关键词 能量管理 燃料电池汽车 参数匹配 Simulink/CRUISE M联合仿真 整车性能
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盾构隧道施工的参数优化与施工质量控制管理
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作者 李帅 《智能建筑与智慧城市》 2026年第3期170-172,共3页
文章基于盾构施工关键参数的系统分析,探讨其与施工质量的内在联系,构建了大数据驱动的施工参数优化模型。根据全面采集和处理施工过程中多源异构数据,采用数据挖掘与机器学习技术,分析施工参数的动态变化规律。研究结果表明,大数据驱... 文章基于盾构施工关键参数的系统分析,探讨其与施工质量的内在联系,构建了大数据驱动的施工参数优化模型。根据全面采集和处理施工过程中多源异构数据,采用数据挖掘与机器学习技术,分析施工参数的动态变化规律。研究结果表明,大数据驱动的优化模型能够有效提高施工参数的准确性和实时性,同时增强施工过程中的质量控制水平。 展开更多
关键词 盾构隧道 施工参数优化 大数据 质量控制 智能化管理
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基于区块链的电网自动发电控制参数全生命周期管控技术研究
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作者 金石 李蓓贝 +6 位作者 冯晓泽 洪悦 张雯露 刘倩 童世奇 张乔 陶韬 《电器与能效管理技术》 2026年第2期24-32,共9页
针对传统自动发电控制(AGC)参数管理依赖中心化数据库,存在数据篡改风险、多方协同效率低、操作透明度不足及历史追溯困难等问题。将区块链技术引入AGC参数管控的全过程,以解决参数核查、存证、追溯等管控难题。首先,设计了电网AGC参数... 针对传统自动发电控制(AGC)参数管理依赖中心化数据库,存在数据篡改风险、多方协同效率低、操作透明度不足及历史追溯困难等问题。将区块链技术引入AGC参数管控的全过程,以解决参数核查、存证、追溯等管控难题。首先,设计了电网AGC参数管控区块链架构;其次,研究了AGC参数管控链构建的关键技术;最后,通过实验验证分析,对参数管控链的一致性核查、存证效率、共识效率等性能进行了分析。结果表明,所设计的参数管控链具备关键参数上链高效存证、可信追溯、一致性核查等功能,能够显著提升管理效率与安全性。 展开更多
关键词 区块链 自动发电控制参数管理 数据存证 一致性核查
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基于生命周期管理的工业锅炉水处理标准化路径研究
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作者 孔妍 安娅琳 +2 位作者 马剑波 王端 杨群峰 《中国标准化》 2026年第2期129-134,共6页
本研究以工业锅炉水处理全生命周期管理为核心,构建了覆盖规划、运行、维护与退役阶段的标准化路径框架。通过系统性整合水质监测、水处理药剂投加与设备维护等关键环节,提出基于数据驱动的动态参数调整与全周期闭环反馈机制,结合案例... 本研究以工业锅炉水处理全生命周期管理为核心,构建了覆盖规划、运行、维护与退役阶段的标准化路径框架。通过系统性整合水质监测、水处理药剂投加与设备维护等关键环节,提出基于数据驱动的动态参数调整与全周期闭环反馈机制,结合案例实施验证其可行性。研究首次构建覆盖全生命周期的锅炉水处理标准化闭环框架,提出基于SEI指数的多要素协同优化模型,以实现从经验驱动到数据驱动的处理策略转型。结果表明,标准化路径可使给水硬度合格率提升至98%,较实施前提升16%,pH波动范围缩小78%,异常响应时间缩短81%,水处理药剂变异系数降低82%,维护周期执行偏差减少87%。该方法为锅炉水处理从经验驱动向规则驱动转型提供了理论支持与实践路径,有利于工业锅炉系统的高效、经济运行。 展开更多
关键词 生命周期管理 锅炉水处理 标准化路径 闭环控制 动态参数优化
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高炉冷却壁分数阶传热特性及预测
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作者 张群蔚 邢宏伟 +3 位作者 梁其其 杨爱民 李杰 韩阳 《钢铁》 北大核心 2026年第2期89-99,共11页
为解决高炉冷却壁传热过程中因非局部热记忆与瞬态多尺度耦合特性导致传统整数阶模型预测偏差的问题,研究旨在构建精准的传热分析与动态预测模型,为冷却系统智能调控提供理论与方法支撑。研究基于Caputo分数阶导数建立非稳态传热模型,... 为解决高炉冷却壁传热过程中因非局部热记忆与瞬态多尺度耦合特性导致传统整数阶模型预测偏差的问题,研究旨在构建精准的传热分析与动态预测模型,为冷却系统智能调控提供理论与方法支撑。研究基于Caputo分数阶导数建立非稳态传热模型,采用短记忆效应修正的Grünwald-Letnikov离散格式求解,以刻画耐火材料的热记忆特性;设计嵌入分数阶算子的物理信息神经网络(physics-informed neural network , PINN)架构,结合滚动时域优化与迁移学习策略,实现时变导热系数、热源项及分数阶参数的高效反演与温度场动态预测;通过分子动力学与相场多尺度模拟,分析Al_(2)O_(3)-SiO_(2)晶格及微裂纹网络对热传导的微观影响;基于分数阶参数与微观结构的映射关系,建立冷却壁健康预警框架。结果表明,模型收敛稳定,最优分数阶数α为0.8时,全局温度预测均方根误差(root mean square error, RMSE)达0.99℃,显著优于整数阶模型,温度场模拟与实际工况一致;多尺度模拟揭示,Al_(2)O_(3)-SiO_(2)晶格的幂律弛豫特性及微裂纹网络诱导的非局部热扩散均与分数阶模型特征吻合;健康预警框架可实现风险等级定量划分。研究证实分数阶-PINN模型在冷却壁传热问题中具有优势,为高炉冷却系统智能运维提供了高精度工具,推动了分数阶理论与深度学习在工业传热领域的交叉应用。 展开更多
关键词 高炉冷却壁 分数阶热传导 物理信息神经网络 传热参数反演 热态预测 多尺度模拟 动态热管理 健康预警
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煤矿综采工作面顶板管理技术
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作者 孟应杰 《凿岩机械气动工具》 2026年第2期121-123,共3页
为提升综采工作面顶板管理的精准性与安全性,借助地质力学参数原位测试精准识别顶板岩性结构,分析综采工作面顶板核心支护技术,包括主动支护技术、被动支护技术及特殊工况下的顶板联合支护技术,搭建多参数监测系统并构建失稳预警模型,... 为提升综采工作面顶板管理的精准性与安全性,借助地质力学参数原位测试精准识别顶板岩性结构,分析综采工作面顶板核心支护技术,包括主动支护技术、被动支护技术及特殊工况下的顶板联合支护技术,搭建多参数监测系统并构建失稳预警模型,以期为综采工作面安全、高效生产提供技术保障。 展开更多
关键词 综采工作面 顶板管理技术 多参数监测系统 失稳预警模型
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Soil Physical Quality of Citrus Orchards Under Tillage, Herbicide, and Organic Managements 被引量:4
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作者 Simone DI PRIMA Jesus RODRIGO-COMINO +4 位作者 Agata NOVARA Massimo IOVINO Mario PIRASTRU Saskia KEESSTRA Artemi CERDA 《Pedosphere》 SCIE CAS CSCD 2018年第3期463-477,共15页
Soil capacity to support life and to produce economic goods and services is strongly linked to the maintenance of good soil physical quality(SPQ). In this study, the SPQ of citrus orchards was assessed under three dif... Soil capacity to support life and to produce economic goods and services is strongly linked to the maintenance of good soil physical quality(SPQ). In this study, the SPQ of citrus orchards was assessed under three different soil managements, namely no-tillage using herbicides, tillage under chemical farming, and no-tillage under organic farming. Commonly used indicators, such as soil bulk density,organic carbon content, and structural stability index, were considered in conjunction with capacitive indicators estimated by the Beerkan estimation of soil transfer parameter(BEST) method. The measurements taken at the L'Alcoleja Experimental Station in Spain yielded optimal values for soil bulk density and organic carbon content in 100% and 70% of cases for organic farming. The values of structural stability index indicated that the soil was stable in 90% of cases. Differences between the soil management practices were particularly clear in terms of plant-available water capacity and saturated hydraulic conductivity. Under organic farming, the soil had the greatest ability to store and provide water to plant roots, and to quickly drain excess water and facilitate root proliferation.Management practices adopted under organic farming(such as vegetation cover between the trees, chipping after pruning, and spreading the chips on the soil surface) improved the SPQ. Conversely, the conventional management strategies unequivocally led to soil degradation owing to the loss of organic matter, soil compaction, and reduced structural stability. The results in this study show that organic farming has a clear positive impact on the SPQ, suggesting that tillage and herbicide treatments should be avoided. 展开更多
关键词 Beerkan estimation of soil transfer parameter capacitive indicator organic farming soil management soil quality assessment structural stability index
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Artificial Intelligence Based Sentiment Analysis for Health Crisis Management in Smart Cities 被引量:1
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作者 Anwer Mustafa Hilal Badria Sulaiman Alfurhood +3 位作者 Fahd N.Al-Wesabi Manar Ahmed Hamza Mesfer Al Duhayyim Huda G.Iskandar 《Computers, Materials & Continua》 SCIE EI 2022年第4期143-157,共15页
Smart city promotes the unification of conventional urban infrastructure and information technology (IT) to improve the quality of living andsustainable urban services in the city. To accomplish this, smart cities nec... Smart city promotes the unification of conventional urban infrastructure and information technology (IT) to improve the quality of living andsustainable urban services in the city. To accomplish this, smart cities necessitate collaboration among the public as well as private sectors to install ITplatforms to collect and examine massive quantities of data. At the same time,it is essential to design effective artificial intelligence (AI) based tools to handlehealthcare crisis situations in smart cities. To offer proficient services to peopleduring healthcare crisis time, the authorities need to look closer towardsthem. Sentiment analysis (SA) in social networking can provide valuableinformation regarding public opinion towards government actions. With thismotivation, this paper presents a new AI based SA tool for healthcare crisismanagement (AISA-HCM) in smart cities. The AISA-HCM technique aimsto determine the emotions of the people during the healthcare crisis time, suchas COVID-19. The proposed AISA-HCM technique involves distinct operations such as pre-processing, feature extraction, and classification. Besides,brain storm optimization (BSO) with deep belief network (DBN), called BSODBN model is employed for feature extraction. Moreover, beetle antennasearch with extreme learning machine (BAS-ELM) method was utilized forclassifying the sentiments as to various classes. The use of BSO and BASalgorithms helps to effectively modify the parameters involved in the DBNand ELM models respectively. The performance validation of the AISA-HCMtechnique takes place using Twitter data and the outcomes are examinedwith respect to various measures. The experimental outcomes highlighted theenhanced performance of the AISA-HCM technique over the recent state ofart SA approaches with the maximum precision of 0.89, recall of 0.88, Fmeasure of 0.89, and accuracy of 0.94. 展开更多
关键词 Smart city sentiment analysis artificial intelligence healthcare management metaheuristics deep learning parameter tuning
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Nitrate contamination in groundwater of Kabul Province,Afghanistan:Reasons behind and conceptual management framework discourse
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作者 JAWADI Hussain Ali IQBAL Mohammad Wasim +3 位作者 NASERI Mohammad FARAHMAND Asadullah AZIZI Abdul Haseeb EQRAR Mohammad Naiem 《Journal of Mountain Science》 SCIE CSCD 2022年第5期1274-1291,共18页
Groundwater contamination has been on the rise in Afghanistan.It has become a major concern among the policy makers.This paper aims to propose practical options for the management of nitrate contamination in one of Af... Groundwater contamination has been on the rise in Afghanistan.It has become a major concern among the policy makers.This paper aims to propose practical options for the management of nitrate contamination in one of Afghanistan’s groundwater polluted provinces,Kabul.The management framework utilized Mann-Kendall and Sen Slope tests to detect nitrate trend and geostatistical analysis option in Arc GIS 10.5 to assess the nitrate change.To explore the impact of various management options,a number of legislative documents were reviewed.The results indicate a decline in the nitrate storage of Kabul aquifers from 108 mg/L in 2005 to 0.044 mg/L in 2010.Considering the whole period of the study,the results show that the nitrate volumes remain lower than the nitrate concentration range proposed by World Health Organization(50 mg/L).Groundwater dynamics in Kabul aquifers were influenced by nitrate derived from precipitation and nitrate input from root zones in agricultural areas.Finally,different management options for groundwater pollution from nitrate and corresponding authorities,incorporated urban,rural and agriculture,were proposed.It is expected that this study will help policy makers to better manage the nitrate storage of Kabul aquifers by implementing the proposed management options. 展开更多
关键词 Nitrate concentration GROUNDWATER AFGHANISTAN Effective parameter management option
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PBRTQC方法在凝血质量控制中的应用 被引量:1
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作者 王文静 赵丹彤 +1 位作者 马捷 于艳华 《标记免疫分析与临床》 2025年第5期1018-1022,共5页
目的探讨基于患者数据的实时质量控制(patient-based real-time quality control,PBRTQC)方法在凝血检测质量管理中的应用,优化参数设置,并评估不同PBRTQC算法对凝血指标的误差检测性能。方法收集首都医科大学附属北京佑安医院2023.4-20... 目的探讨基于患者数据的实时质量控制(patient-based real-time quality control,PBRTQC)方法在凝血检测质量管理中的应用,优化参数设置,并评估不同PBRTQC算法对凝血指标的误差检测性能。方法收集首都医科大学附属北京佑安医院2023.4-2024.4期间凝血检测数据,包括凝血酶原时间(prothrombin time,PT)、活化部分凝血活酶时间(activated partial thromboplastin time,APTT)、纤维蛋白原(fibrinogen,FIB)及D-二聚体(D-dimer,D-D)4项指标。采用移动中位数(moving median,MM)、移动均值(simple moving average,SMA)、加权移动均值(weighted moving average,WMA)和加权移动均值(exponentially weighted moving average,EWMA)4种PBRTQC算法,对不同参数组合进行穷举计算,并通过设定预期假阳性率(desired false positive rate,DFPR)、控制限(truncation limit,TL)、步长及加权系数等参数,优化PBRTQC方案。利用训练集和验证集评估PBRTQC方案的误差检测性能,并在真实世界数据中进行应用验证。结果PBRTQC方法对系统误差的检测表现优于传统质控方法,尤其对负误差的检测更为敏感。PT适用于WMA算法,可快速检测负误差并将假阳性率控制在1%以下;APTT和FIB采用EWMA算法,在适应性和灵敏度方面表现更优;D-D由于随机误差较大,WMA算法表现出较强的抗干扰能力。最终优化参数在验证集上的假阳性率(false positive rate,FPR)、假阴性率(false negative rate,FNR)、及时性(average number of patient samples to error detection,ANPed)表现稳定,能够有效识别仪器漂移、试剂批次变化等质量问题。结论本研究优化了PBRTQC方法在凝血检测中的应用,提高了误差监测的灵敏度和稳定性,为实验室质量控制提供了新的技术手段。未来研究可进一步拓展数据来源,优化算法,并探索PBRTQC在更广泛的临床检测项目中的应用。 展开更多
关键词 基于患者数据的实时质量控制(PBRTQC) 凝血检测 误差监测 参数优化 质量管理
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交通场景下基于轨迹分析与虚实融合的车辆交通参数提取研究
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作者 曾庆刚 徐学卫 +6 位作者 李家虎 武建平 王庆 何光明 李启源 田鸣 杨杰 《计算机测量与控制》 2025年第12期270-277,共8页
针对道路交通场景中车辆交通参数的精确提取问题进行了研究,提出了一种基于轨迹分析的交通参数提取方法;该方法利用道路监控中的云台相机捕捉车辆行驶轨迹,结合自动化处理和深度分析技术,实现了车速、流量及密度等核心交通参数的准确评... 针对道路交通场景中车辆交通参数的精确提取问题进行了研究,提出了一种基于轨迹分析的交通参数提取方法;该方法利用道路监控中的云台相机捕捉车辆行驶轨迹,结合自动化处理和深度分析技术,实现了车速、流量及密度等核心交通参数的准确评估;具体方法包括采用先进图像处理技术对监控视频中的车辆进行精确识别和持续跟踪,基于车辆轨迹信息自动生成满足不同方向交通流量统计需求的检测线;通过计算车辆移动距离与时间,获得瞬时速度和平均速度等关键参数,并利用时间占有率有效估算交通密度;实验结果表明,该方法在车流量统计方面具有较高精度,能够有效克服传统方法中目标误检及中大型车辆遮挡小型车辆等问题;此外,该方法具有良好的稳定性和广泛适应性,能够适应多种复杂道路交通场景;该技术为交通管理部门提供了一种高效且精准的交通参数提取手段,有助于更加准确地掌握道路运行状态,支持科学的交通管理策略制定,提升道路通行能力和交通安全水平。 展开更多
关键词 交通参数 轨迹分析 交通管理 交通流量统计 智能交通系统
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国六重型柴油机排气热管理技术
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作者 李明星 张腾 +2 位作者 邹利宁 周承忠 黎幸荣 《内燃机与动力装置》 2025年第3期10-18,共9页
为有效提高发动机排气温度和选择性催化还原器(selective catalytic reduction,SCR)入口温度,以某款国六重型柴油机为研究对象,根据排气温度分布特征将缸内燃烧控制区域划分为若干区间,每个区间制定差异化的温度控制策略;通过试验验证... 为有效提高发动机排气温度和选择性催化还原器(selective catalytic reduction,SCR)入口温度,以某款国六重型柴油机为研究对象,根据排气温度分布特征将缸内燃烧控制区域划分为若干区间,每个区间制定差异化的温度控制策略;通过试验验证进气节流阀调控和燃烧参数优化两种排气热管理技术的效果,在此基础上设计集成了SCR自动加热模式的发动机自适应排气热管理策略,并开展发动机台架冷态世界统一瞬态循环(world harmonized transient cycle,WHTC)试验和高原复杂路况实车验证试验,评估热管理策略的实际效果。结果表明:后喷油量、后喷正时对排气温度的影响明显大于轨压、主喷正时、预喷正时;后喷油量和后喷正时增大,排气热管理效果逐步增强;当进气节流阀的关闭度不低于70%时,排气温度随进气节流阀的关闭度增大呈升高趋势;发动机在中、高负荷运行时,可以通过优化后喷油量和后喷正时等燃烧参数的方法达到较好的热管理效果;低负荷及0负荷工况下,通过进气节流阀调控并耦合优化燃烧参数的策略可以实现良好的排气热管理效果;冷态WHTC工况下,发动机平均排气温度提高约20℃,在WHTC加权平均油耗增长率仅为4%的前提下,NO x比排放大幅降低(降幅约为30%);高原长下坡工况下,SCR入口温度可长时间维持在370℃左右。设计的自适应排气热管理策略可使发动机在冷机、高原、低温等恶劣工况下具有良好的热管理效果。 展开更多
关键词 柴油机 排气热管理 SCR 燃烧参数 进气节流阀
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双回路控制下拖拉机发动机管理系统的设计
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作者 黎世锟 《农机化研究》 北大核心 2025年第2期249-253,共5页
随着拖拉机发动机控制系统的复杂性在不断增加,拖拉机发动机扭矩管理系统需要满足多种工况需求,配备多种传感器和执行器,同时具备高效能和燃油经济性。为此,设计了基于双回路速度跟踪控制的拖拉机发动机扭矩管理系统,通过两个回路实现... 随着拖拉机发动机控制系统的复杂性在不断增加,拖拉机发动机扭矩管理系统需要满足多种工况需求,配备多种传感器和执行器,同时具备高效能和燃油经济性。为此,设计了基于双回路速度跟踪控制的拖拉机发动机扭矩管理系统,通过两个回路实现对发动机扭矩的精确控制,其中一个回路用于速度跟踪,另一个回路用于调节发动机扭矩。通过精确的速度控制和扭矩管理,系统可以在不同工况下实现高效的能量利用和优化的运行性能。试验结果表明:系统能够有效地实现发动机扭矩的准确控制,提高了拖拉机的整体性能和燃油经济性。研究结果旨在改进拖拉机发动机控制系统的性能,提高其适应多种工况的能力,并实现更高的燃油经济性。 展开更多
关键词 拖拉机发动机 双回路速度跟踪控制 扭矩管理系统 多工况需求 参数配置
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电池等效电路模型极化参数估计的收敛性分析
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作者 张维刚 曾嘉博 +3 位作者 周维 陈正 吴颂 潘文军 《湖南大学学报(自然科学版)》 北大核心 2025年第2期1-9,共9页
为探究动力电池极化参数估计在不同工况下的误差收敛特性,采用李雅普诺夫第二法对估计器的稳定性和收敛性进行分析.基于等效电路模型和遗忘因子递归最小二乘法推导得到极化参数估计误差的状态方程.采用李雅普诺夫第二法对状态方程进行分... 为探究动力电池极化参数估计在不同工况下的误差收敛特性,采用李雅普诺夫第二法对估计器的稳定性和收敛性进行分析.基于等效电路模型和遗忘因子递归最小二乘法推导得到极化参数估计误差的状态方程.采用李雅普诺夫第二法对状态方程进行分析,得到估计器渐进收敛的必要条件,即持续变化的电流输入,并提出一种图解法用于分析误差的动态收敛特性和论证此必要条件的合理性.采用实验校准的电池模型产生的数据对理论分析过程和结果进行验证.结果表明,估计器在持续变化的电流输入下能逐渐收敛到真值附近,且在变化剧烈的正负交变工况下具备更好的收敛性. 展开更多
关键词 电池管理系统 等效电路模型 参数辨识 渐进收敛性 李雅普诺夫第二法
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