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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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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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Local parameter identification with neural ordinary differential equations
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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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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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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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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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PBRTQC方法在凝血质量控制中的应用
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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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基于数字化交付的公路BIM模型参数化方法研究
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作者 李金龙 王欣南 《中外公路》 2025年第3期215-220,共6页
通过分析公路工程建设各阶段的应用点及数字化交付现状,发现现阶段BIM模型源文件在各阶段的修改与细化过程中,存在缺乏对各参数的管理与定义问题,导致各阶段的BIM模型拆分与细化困难,甚至需要重建。针对该问题,该文提出了加强全生命期... 通过分析公路工程建设各阶段的应用点及数字化交付现状,发现现阶段BIM模型源文件在各阶段的修改与细化过程中,存在缺乏对各参数的管理与定义问题,导致各阶段的BIM模型拆分与细化困难,甚至需要重建。针对该问题,该文提出了加强全生命期统筹管理方法,通过梳理各阶段应用点来明确模型参数的需求,建立参数预留和分类管理机制。进而提出“总体描述”“局部描述”“截面描述”“模型元素”等参数概念,明确各参数的使用场景及分类原则,以改善参数预留所导致的参数冗杂、重复定义等问题。研究表明:该方法实现了对模型创建参数的明确定义和有序管理,提高了模型创建、修改及参数的使用效率,为BIM模型在全生命期应用的参数化提供了解决方案。 展开更多
关键词 公路工程 BIM 全生命周期 数字化交付 参数化 模型创建 参数管理
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基于主动交通管理需求的快速路交通流特性研究
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作者 邵长桥 董文延 《重庆交通大学学报(自然科学版)》 北大核心 2025年第5期95-101,共7页
为了适应主动交通管理策略需求,对快速路交通流特性进行研究。以交通微波雷达检测器数据为基础,应用交通流波速理论和宏观交通流模型,将交通流状态分为非拥堵状态、过渡状态和拥堵状态。根据交通流波速理论分析拥堵状态下各车道密度、... 为了适应主动交通管理策略需求,对快速路交通流特性进行研究。以交通微波雷达检测器数据为基础,应用交通流波速理论和宏观交通流模型,将交通流状态分为非拥堵状态、过渡状态和拥堵状态。根据交通流波速理论分析拥堵状态下各车道密度、速度和占有率的变化特性,研究了车道级交通流状态划分阈值;分别应用Pipes、Van Aerde和Newell宏观交通流模型对交通流断面观测数据与车道观测数据进行拟合,并对基于宏观交通流模型的交通流参数进行估计。研究结果表明:不同车道的交通运行时序特性和交通流状态存在显著差异,3个经典模型中Van Aerde模型对交通流运行数据拟合效果最佳。综合交通流波速理论和宏观交通流模型分析结果,得到了交通流状态判定阈值。 展开更多
关键词 交通运输工程 主动交通管理 交通流特征参数 交通流特性 交通流波速理论
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基于演化博弈研究的机场净空安全监管
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作者 文军 樊志翔 《科技和产业》 2025年第6期36-41,共6页
为提升机场净空安全监管水平,保障机场净空区域的安全运行,构建了机场管理部门与净空违规者之间的演化博弈模型,深入分析双方在不同情景条件下的策略选择及其成因。运用MATLAB软件对重要参数的敏感度进行了数值分析,探讨了净空违规者违... 为提升机场净空安全监管水平,保障机场净空区域的安全运行,构建了机场管理部门与净空违规者之间的演化博弈模型,深入分析双方在不同情景条件下的策略选择及其成因。运用MATLAB软件对重要参数的敏感度进行了数值分析,探讨了净空违规者违规运行被发现的概率、处罚力度、合规运行成本以及违规运行收入4个重要参数对系统演化路径及演化结果的影响。结果表明,提高违规操作被发现的概率和加大处罚力度,可以有效促使违规者向合规运行策略转变;同时,通过降低合规运行成本和限制违规收益,能够进一步减少违规行为的发生概率。 展开更多
关键词 机场净空 安全管理 演化博弈 仿真分析 参数敏感性
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基于自主修正算法的接触网智能参数测量装置研究
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作者 欧志新 《德州学院学报》 2025年第4期61-66,共6页
动态运行的弓网几何参数误差和精度决定了列车运行的稳定性。传统的参数测量装置主要基于激光和超声波测距的原理,设备在钢轨上移动缓慢、聚焦测量点误差大,测量出的数值需要经过若干处理才能辨识。提出了一种基于激光扫描的接触网智能... 动态运行的弓网几何参数误差和精度决定了列车运行的稳定性。传统的参数测量装置主要基于激光和超声波测距的原理,设备在钢轨上移动缓慢、聚焦测量点误差大,测量出的数值需要经过若干处理才能辨识。提出了一种基于激光扫描的接触网智能几何参数检测方法,即结合激光扫描、测距装置、光电编码器等硬件设备和数据软件算法,实现非接触式采集,采样点定位和数据自主修正算法优化处理,从而获得接触网的主要几何参数。经实验,该方法能有效提高接触网几何参数检测精度,测量精度达到3mm,具有实际意义。 展开更多
关键词 弓网系统 激光测量仪 数据管理软件 自主修正算法 参数辨识和仿真
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CCUS-EOR油藏井筒地面一体化生产协同管控系统设计研究 被引量:1
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作者 丁观世 焉科鑫 +4 位作者 檀朝东 李秋实 刘天宇 程世东 冯钢 《钻采工艺》 北大核心 2025年第1期207-215,共9页
针对当前CCUS-EOR数字化系统中注入、驱油、埋存、采出、集输、回注各环节的数据和功能模块分散独立、协同性差等问题,设计了CCUS-EOR油藏井筒地面一体化生产协同管控系统。按照工业互联网顶层设计要求,采用微服务和容器化技术,构建了CC... 针对当前CCUS-EOR数字化系统中注入、驱油、埋存、采出、集输、回注各环节的数据和功能模块分散独立、协同性差等问题,设计了CCUS-EOR油藏井筒地面一体化生产协同管控系统。按照工业互联网顶层设计要求,采用微服务和容器化技术,构建了CCUS-EOR管控系统的架构和标准化的数据模型,设计了数据与模型管理、方案设计、生产运行三个功能单元,包括生产监控、油藏动态、注采井筒、地面集输、协同调控、数据管理等应用模块。研究表明:构建的CCUS-EOR生产协同管控系统可实现CCUS-EOR全流程数据融合、生产监控、工况诊断、完整性预警、协同决策、智能调控,为CCUS-EOR安全生产和提高采收率提供数据和平台支撑。 展开更多
关键词 CCUS-EOR 多参优化 协同调控 微服务 管控系统
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储能电池组浸没式液冷系统冷却性能模拟研究 被引量:5
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作者 陈岳浩 陈莎 +2 位作者 陈慧兰 孙小琴 罗永强 《储能科学与技术》 北大核心 2025年第2期648-658,共11页
随着储能需求的快速增长,单体电池容量越来越大,大容量电池逐渐成为电化学储能系统的主流,然而对现有电池组冷却系统的研究仍集中在小容量电池系统。本工作对280Ah大容量电池组浸没式液冷系统进行研究,探讨了电池间距,冷却液进出口方式... 随着储能需求的快速增长,单体电池容量越来越大,大容量电池逐渐成为电化学储能系统的主流,然而对现有电池组冷却系统的研究仍集中在小容量电池系统。本工作对280Ah大容量电池组浸没式液冷系统进行研究,探讨了电池间距,冷却液进出口方式、进口流速、种类对冷却性能的影响,进一步分析了冷却液热物性参数对冷却效果的影响权重。结果表明:适当增加电池间距对浸没式液冷电池组冷却效果有积极影响,当电池间距由0增加至5 mm时,电池组最大温差ΔT_(max)、最高温度T_(max)分别降低1.57℃、1.84℃;冷却液进口位置对ΔT_(max)和T_(max)影响大于出口位置的影响,进口位置对电池箱体内流场影响大于出口位置的影响;ΔT_(max)和T_(max)随进口流速增加而降低,进口流速由0.2 m/s增加至0.4 m/s时,ΔT_(max)和T_(max)分别降低21.2%、8.0%;去离子水冷却效果最佳,硅油冷却效果最差,去离子水相较于硅油的ΔT_(max)和T_(max)分别降低5.17℃、5.99℃;冷却液热物性参数对电池组冷却效果影响权重依次为密度、比热容、热导率和动力黏度。本研究结果对大容量电池组浸没式液冷系统设计具有一定指导意义。 展开更多
关键词 浸没式冷却 电池热管理 参数敏感性 数值模拟
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