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Development of an Improved GUI Automation Test System Based on Event-Flow Graph 被引量:2
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作者 Yongzhong Lu Danping Yan +1 位作者 Songlin Nie Chun Wang 《Journal of Software Engineering and Applications》 2008年第1期38-43,共6页
A more automated graphic user interface (GUI) test model, which is based on the event-flow graph, is proposed. In the model, a user interface automation API tool is first used to carry out reverse engineering for a GU... A more automated graphic user interface (GUI) test model, which is based on the event-flow graph, is proposed. In the model, a user interface automation API tool is first used to carry out reverse engineering for a GUI test sample so as to obtain the event-flow graph. Then two approaches are adopted to create GUI test sample cases. That is to say, an improved ant colony optimization (ACO) algorithm is employed to establish a sequence of testing cases in the course of the daily smoke test. The sequence goes through all object event points in the event-flow graph. On the other hand, the spanning tree obtained by deep breadth-first search (BFS) approach is utilized to obtain the testing cases from goal point to outset point in the course of the deep regression test. Finally, these cases are applied to test the new GUI. Moreover, according to the above-mentioned model, a corresponding prototype system based on Microsoft UI automation framework is developed, thus giving a more effective way to improve the GUI automation test in Windows OS. 展开更多
关键词 Automated Software TESTING GRAPHIC User Interface event-flow Graph Regression TESTING ANT COLONY Optimization UI AUTOMATION
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Debris Flow Monitoring System and Observed Event in Taiwan:A Case Study at Aiyuzi River
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作者 HSIAO Taichung LEE Bingjean +2 位作者 CHOU Tienyin LIEN Huipain CHANG Yinghuei 《Wuhan University Journal of Natural Sciences》 CAS 2007年第4期610-618,共9页
Since 2002, the Soil and Water Conservation Bureau, which is responsible for the conservation and administrative management of hillside in Taiwan, has been cooperating with Feng Chia University. Together, they have su... Since 2002, the Soil and Water Conservation Bureau, which is responsible for the conservation and administrative management of hillside in Taiwan, has been cooperating with Feng Chia University. Together, they have successfully carried out the establishment and maintenance of 13 fixed debris flow monitoring stations over the island and 2 mobile debris flow monitoring stations. During July 2004, a powerful southwest air current brought by Mindulle Typhoon caused serious flood in central and southern Taiwan. This paper aims to describe the establishment of debris flow monitoring systems in Taiwan and the observation of the debris flow event during Mindulle Typhoon at Aiyuzi River in Shenmu Village, Nantou County by the monitoring station. 展开更多
关键词 debris flow monitoring station mobile debris flow monitoring station debris flow event Underground sound of debris flows
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Risk Assessment of Extreme Events along a River Flow
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作者 Ivan K. Diadovski Maya P. Atanassova Vasil Simeonov 《Journal of Water Resource and Protection》 2010年第5期455-461,共7页
The present work considers the Struma River water flow on Bulgarian territory as a starting point for evalua-tion of maximum and minimum water flow using an original integral method. The risk assessment is deter-mined... The present work considers the Struma River water flow on Bulgarian territory as a starting point for evalua-tion of maximum and minimum water flow using an original integral method. The risk assessment is deter-mined by specific indices like the index Mmax,i for the deviation of the maximum water flow from the calcu-lated norm of the maximum flow Qmax,0 and the index Mmin,i for the deviation of the minimum water flow from calculated norm of the minimum flow Qmin,0. The new integral approach introducing specific indicators for risk assessment like the indices Mmin,i and Mmax,i has been checked at three sampling locations of the Na-tional monitoring net along the Struma River: Pernik (in the beginning), Krupnik (in the middle) and Marino pole (at the border in Greece) for the period 1948-2006. A significant trend towards decreasing of Mmax,i in-dex is outlined for the three points. On contrary, a significant trend towards increasing of Mmin,i index is found at Krupnik and Marno pole sampling points. 展开更多
关键词 INTEGRAL Indices CLIMATE Impact Water Quality River flow EXTREME eventS
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Cyclic Reconfigurable Flow Shop under Different Configurations Modeling and Optimization Based on Timed Event Graph
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作者 REN Si-Cheng XU De WANG Fang TAN Min 《自动化学报》 EI CSCD 北大核心 2006年第1期15-20,共6页
Based on the idea that modules are independent of machines, different combinations of modules and machines result in different configurations and the system performances differ under different configurations, a kind o... Based on the idea that modules are independent of machines, different combinations of modules and machines result in different configurations and the system performances differ under different configurations, a kind of cyclic reconfigurable flow shops are proposed for the new manufacturing paradigm-reconfigurable manufacturing system. The cyclic reconfigurable flow shop is modeled as a timed event graph. The optimal configuration is defined as the one under which the cyclic reconfigurable flow shop functions with the minimum cycle time and the minimum number of pallets. The optimal configuration, the minimum cycle time and the minimum number of pallets can be obtained in two steps. 展开更多
关键词 循环流程 制造业 时间事件 建模 优化设计
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Analysis of Nonlinear Stochastic Systems with Jumps Generated by Erlang Flow of Events
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作者 Alexander S. Kozhevnikov Konstantin A. Rybakov 《Open Journal of Applied Sciences》 2013年第1期1-7,共7页
In this paper we consider the stochastic systems with jumps (random impulses) generated by Erlang flow of events that lead to discontinuities in paths. These systems may be used in various applications such as a contr... In this paper we consider the stochastic systems with jumps (random impulses) generated by Erlang flow of events that lead to discontinuities in paths. These systems may be used in various applications such as a control of complex technical systems, financial mathematics, mathematical biology and medicine. We propose to use a spectral method formalism to the probabilistic analysis problem for the stochastic systems with jumps. This method allows to get a solution of the analysis problem in an explicit form. 展开更多
关键词 ANALYSIS ERLANG flow of eventS Generalized Fokker-Planck Equations Random Impulses JUMP-DIFFUSION Process SPECTRAL Characteristic SPECTRAL Method Formalism Stochastic System
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置换型flow-shop控制的一些新结果 被引量:1
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作者 陈芨熙 顾新建 《浙江大学学报(自然科学版)》 CSCD 1999年第6期627-632,共6页
提出置换型flow -shop 控制的新方法,并与文献[1]提出的基于极大代数模型的方法进行了比较,表明该方法比极大代数模型的方法更简单, 所得结果有进一步扩大且更有实际意义,并通过实例分析证明了这一点.
关键词 流水型车间控制 机械制造系统 置换型 DEDS
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FLOW-SHOP网络模型的快速解法和它的某些动态参数的计算 被引量:5
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作者 赵臻 戴志勇 《武汉科技学院学报》 2001年第1期13-17,46,共6页
根据极大代数理论,反映缓冲区容量的FLOW-SHOP网络系统,是这种代数意义下的线性系统。本文对这类系统的Cohen模型.提出了一种快速解法,由此导出了它的某些动态性参数的计算。
关键词 flow-SHOP网络 离散事件动态系统 系统阵列 迭代阵列 Cohen模型 动态参数
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冠状动脉CT血管成像血流储备分数对冠状动脉临界病变的预后评估价值
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作者 刘涛 孙勇 《中国中西医结合影像学杂志》 2026年第1期64-69,共6页
目的:探讨冠状动脉CT血管成像(CCTA)获得的血流储备分数(CT-FFR)对冠状动脉临界病变预后的评估价值。方法:回顾性纳入行CCTA检查并诊断为冠状动脉临界病变的冠状动脉硬化性心脏病(冠心病)患者289例。将CCTA原始DICOM数据导入脉影CT-FFR... 目的:探讨冠状动脉CT血管成像(CCTA)获得的血流储备分数(CT-FFR)对冠状动脉临界病变预后的评估价值。方法:回顾性纳入行CCTA检查并诊断为冠状动脉临界病变的冠状动脉硬化性心脏病(冠心病)患者289例。将CCTA原始DICOM数据导入脉影CT-FFR模块行后处理,得到CT-FFR值。记录患者临床基线资料,记录随访期间内主要心血管不良事件(MACE)的发生情况。根据CT-FFR值分为CT-FFR≤0.8组177例和CT-FFR>0.8组112例;以是否发生MACE分为MACE组60例和无MACE组229例;比较各组的基线资料。采用Cox回归分析筛选MACE发生的独立危险因素,建立风险预测模型,绘制时间依赖ROC曲线评价预测模型的预测效能。结果:CT-FFR≤0.8组MACE发生率高于CT-FFR>0.8组(P<0.05)。MACE组糖尿病史、多支病变、CT-FFR≤0.8占比均显著高于无MACE组(均P<0.05)。多因素Cox回归分析表明,CT-FFR≤0.8、糖尿病史、多支病变是冠状动脉临界病变患者发生MACE的独立危险因素(均P<0.05),用于建立Cox风险预测模型。时间依赖ROC曲线显示,预测模型整体AUC较高,在第8、16个月时模型的敏感度为1.000,特异度在不同时间点上相对较低。结论:糖尿病史、多支病变、CT-FFR≤0.8是冠状动脉临界病变患者发生MACE的独立危险因素,有助于识别发生MACE风险较高的患者。三者联合建立的预测模型对冠状动脉临界病变的预后具有良好的预测价值,可进一步提升对MACE的预测能力,实现对冠状动脉临界病变的精准分层,改善患者预后。 展开更多
关键词 冠状动脉临界病变 血流储备分数 体层摄影术 X线计算机 血管造影术 心血管不良事件
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尿激酶原联合尼可地尔在老年急性ST段抬高型心肌梗死患者急诊PCI术中的应用价值
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作者 王玉新 崔晓林 金姿 《临床误诊误治》 2026年第1期24-29,共6页
目的探讨尿激酶原联合尼可地尔在老年急性ST段抬高型心肌梗死(STEMI)患者急诊经皮冠状动脉介入治疗(PCI)术中的应用价值。方法选取2020年12月至2023年12月期间接受急诊PCI的126例老年急性STEMI患者作为研究对象,进行回顾性分析。根据PC... 目的探讨尿激酶原联合尼可地尔在老年急性ST段抬高型心肌梗死(STEMI)患者急诊经皮冠状动脉介入治疗(PCI)术中的应用价值。方法选取2020年12月至2023年12月期间接受急诊PCI的126例老年急性STEMI患者作为研究对象,进行回顾性分析。根据PCI术中是否采用尿激酶原治疗分为两组,对照组采用尼可地尔治疗(n=82),研究组在此基础上联合尿激酶原治疗(n=44)。比较两组心肌损伤标志物[肌酸激酶(CK)、肌钙蛋白I(cTnI)、心肌型肌酸激酶同工酶(CK-MB)]、心功能指标[左心室射血分数(LVEF)、左心室收缩末期容积指数(LVESVI)、左心室舒张末期容积指数(LVEDVI)]、无复流/慢血流发生率、主要心血管不良事件(MACE)及不良反应发生情况。结果研究组PCI术中无复流/慢血流发生率为18.19%(8/44),低于对照组的35.36%(29/82,P<0.05)。手术后1周,两组CK、cTnI、CK-MB、LVESVI、LVEDVI水平均较手术前下降,且研究组低于对照组(P<0.05)。手术后1周,两组LVEF水平均较手术前上升,且研究组较对照组更高(P<0.05)。手术后6个月内,两组MACE发生率比较无统计学差异(P>0.05)。两组从用药开始至术后7 d不良反应发生率比较均无统计学差异(P>0.05)。结论尿激酶原联合尼可地尔可有效预防老年急性STEMI患者急诊PCI术中无复流/慢血流的现象,有效改善心肌灌注,提高心功能,且安全性高。 展开更多
关键词 急性ST段抬高型心肌梗死 尿激酶原 经皮冠状动脉介入治疗 无复流 慢血流 心肌损伤 主要心血管不良事件
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Auroral event detection using spatiotemporal statistics of local motion vectors 被引量:1
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作者 WANG Qian LIANG Jimin HU Zejun 《Advances in Polar Science》 2013年第3期175-182,共8页
The analysis and exploration of auroral dynamics are very significant for studying auroral mechanisms. This paper proposes a method based on auroral dynamic processes for detecting auroral events automatically. We fir... The analysis and exploration of auroral dynamics are very significant for studying auroral mechanisms. This paper proposes a method based on auroral dynamic processes for detecting auroral events automatically. We first obtained the motion fields using the multiscale fluid flow estimator. Then, the auroral video frame sequence was represented by the spatiotemporal statistics of local motion vectors. Finally, automatic auroral event detection was achieved. The experimental results show that our methods could detect the required auroral events effectively and accurately, and that the detections were independent on any specific auroral event. The proposed method makes it feasible to statistically analyze a large number of continuous observations based on the auroral dynamic process. 展开更多
关键词 automatic detection auroral event fluid flow
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The relationship between ENSO cycle and high and low-flow in the upper Yellow River 被引量:8
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作者 LANYongchao DINGYongjiang +2 位作者 KANGErsi MAQuanjie ZHANGJishi 《Journal of Geographical Sciences》 SCIE CSCD 2003年第1期105-111,共7页
Firstly, the hydrological and meteorological features of the upper reaches of the Yellow River above Tangnag are analyzed based on observation data, and effects of EI Nino and La Ni na events on the high and low flow ... Firstly, the hydrological and meteorological features of the upper reaches of the Yellow River above Tangnag are analyzed based on observation data, and effects of EI Nino and La Ni na events on the high and low flow in the upper Yellow River are discussed. The results show El Nino and La Nina events possess consanguineous relationship wi th runoff in the upper Yellow River. As a whole, the probability of low fl ow occurrence in the upper Yellow River is relatively great along wit h the occurrence of El Nino event. Moreover, the flood in the upper Yellow River occurs frequently with the occurrence of La Nina event. Besides, the results also show dissimilarity of El Nino event occurri ng time exerts greater impact on high flow and low flow in the uppe r Yellow River, that is, the probability of drought will be greater in the sam e year if El Nino event occurs in spring, the high-flow may happen in this y ear if El Nino occurs in summer or autumn; the longer the continuous period of El Nino is, the lower the runoff in the upper Yellow River is. 展开更多
关键词 El Nino event La Nina event the upper Yellow River high-flow and low-flow
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Flow-shop生产线人机时间分配的应用
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作者 肖慧婷 金士良 洪跃 《现代机械》 2007年第6期1-3,共3页
由于Flow-shop生产线加工工艺的固定特点,其对生产过程中的人机时间分配对提高生产效率有着极大的作用。采用极大代数的方法对串行生产线进行建模,并分析其闭环系统的演化过程,采用甘特图,更直观的反应人机作业时的情况,对实际生产作业... 由于Flow-shop生产线加工工艺的固定特点,其对生产过程中的人机时间分配对提高生产效率有着极大的作用。采用极大代数的方法对串行生产线进行建模,并分析其闭环系统的演化过程,采用甘特图,更直观的反应人机作业时的情况,对实际生产作业计划的制定以及为制品库存管理提供可靠依据,从而为极大代数有关理论的研究及实践应用开拓新的途径。 展开更多
关键词 离散事件动态系统 flow-shop生产线 极大代数 甘特图
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Initial fluctuation effect on elliptic flow in Au+Au collision at 1 GeV/A 被引量:2
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作者 WANG Jia MA Yugang +3 位作者 ZHANG Guoqiang FANG Deqing HAN Lixin SHEN Wenqing 《Nuclear Science and Techniques》 SCIE CAS CSCD 2013年第3期50-54,共5页
How the initial fluctuation affects on the elliptic flow is investigated by investigating the rapidity, transverse 4-velocity, centrality dependencies of elliptic flow for Au+Au at 1 GeV/A with the help of an Isospin ... How the initial fluctuation affects on the elliptic flow is investigated by investigating the rapidity, transverse 4-velocity, centrality dependencies of elliptic flow for Au+Au at 1 GeV/A with the help of an Isospin Quantum Molecular Dynamics (IQMD). In addition, we compare the flow calculated with respect to participant plane created by the initial geometry in coordinate space with the flow reconstructed by the experimental event-plane method, and compare the flow with the experimental data of the FOPI collaboration. It shows that there exists some discrepancy between the flows reconstructed by the above two methods. 展开更多
关键词 波动影响 椭圆流 伏特 电子 量子分子动力学 碰撞 流量计算 空间实验
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Development of Upstream Data-Input Models to Estimate Downstream Peak Flow in Two Mediterranean River Basins of Chile
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作者 Roberto Pizarro-Tapia Rodrigo Valdés-Pineda +1 位作者 Claudio Olivares Patricio A. González 《Open Journal of Modern Hydrology》 2014年第4期132-143,共12页
Accurate flood prediction is an important tool for risk management and hydraulic works design on a watershed scale. The objective of this study was to calibrate and validate 24 linear and non-linear regression models,... Accurate flood prediction is an important tool for risk management and hydraulic works design on a watershed scale. The objective of this study was to calibrate and validate 24 linear and non-linear regression models, using only upstream data to estimate real-time downstream flooding. Four critical downstream estimation points in the Mataquito and Maule river basins located in central Chile were selected to estimate peak flows using data from one, two, or three upstream stations. More than one thousand paper-based storm hydrographs were manually analyzed for rainfall events that occurred between 1999 and 2006, in order to determine the best models for predicting downstream peak flow. The Peak Flow Index (IQP) (defined as the quotient between upstream and downstream data) and the Transit Times (TT) between upstream and downstream points were also obtained and analyzed for each river basin. The Coefficients of Determination (R2), the Standard Error of the Estimate (SEE), and the Bland-Altman test (ACBA) were used to calibrate and validate the best selected model at each basin. Despite the high variability observed in peak flow data, the developed models were able to accurately estimate downstream peak flows using only upstream flow data. 展开更多
关键词 PEAK flows STORM events FLOOD Forecasting PEAK flow Index PEAK flow TRANSIT Time Linear and No-Linear Models
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Identifying the driving factors of sediment delivery ratio on individual flood events in a long-term monitoring headwater basin 被引量:3
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作者 WANG Ling-ling YAO Wen-yi +2 位作者 TANG Jia-liang WANG Wen-long HOU Xin-xin 《Journal of Mountain Science》 SCIE CSCD 2018年第8期1825-1835,共11页
The Sediment Delivery Ratio(SDR) has multi-fold environmental implications both in evaluating the soil and water losses and the effectiveness of conservation measures in watersheds. Various factors, including hydrolog... The Sediment Delivery Ratio(SDR) has multi-fold environmental implications both in evaluating the soil and water losses and the effectiveness of conservation measures in watersheds. Various factors, including hydrological regime and watershed properties, may influence the SDR at interannual timescales. However, the effect of certain important dynamic factors, such as rainfall peak distribution, runoff erosion power and sediment bulk density, on the sediment delivery ratio of single flood events(SDRe) has received little attention. The Qiaogou headwater basin is in the hilly-gully region of the Chinese Loess Plateau, and it encompasses a 0.45 km^2 catchment. Three large-scale field runoff plots at different geomorphological positions were chosen to obtain the observation data, and the 20-year period between 1986 and 2005 is presented. The results showed that the SDRe of the Qiaogou headwaters varied from 0.49 to 2.77. Among the numerous influential factors, rainfall and runoff were the driving factors causing slope erosion and sediment transport. The rainfall erosivity had a significant positive relationship with the sediment transport modulus(R^2=0.85, P<0.01) but had no significant relationship with SDRe. The rainfall peak coefficient was significantly positively correlated with the SDRe(R^2=0.64, P<0.05), indicating the influence of rainfall energy distribution on the SDRe. The runoff erosion power index was not only significantly related to the sediment transport modulus(R^2=0.84, P<0.01) but also significantly related to the SDRe(R^2=0.57, P<0.01). In addition, the relative bulk density was significantly related to the SDRe, indicating that hyper-concentrated flow characteristics contributed to more transported sediment in the catchment. Thus, the rainfall peak coefficient, runoff erosion power and sediment relative bulk density could be used as dynamic indexes to predict the SDRe in the hilly areas of the Chinese Loess Plateau. 展开更多
关键词 Sediment delivery ratio Single flood events Rainfall erosivity Runoff erosion power Hyper-concentrated flow
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大型活动散场期间城市轨道交通大客流时空分布预测及其应用 被引量:1
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作者 周峰 王文昱 +1 位作者 赵周 文旭光 《城市轨道交通研究》 北大核心 2025年第5期24-29,共6页
[目的]随着市民对文娱生活的多样化需求日益渐增,各城市举办的大型活动数量不断增加,大型活动诱发的大客流会对城市轨道交通常态运营造成干扰,存在安全风险,因此需从历史数据中挖掘客流特征,并提出客流预测方法,为轨道交通运营部门在大... [目的]随着市民对文娱生活的多样化需求日益渐增,各城市举办的大型活动数量不断增加,大型活动诱发的大客流会对城市轨道交通常态运营造成干扰,存在安全风险,因此需从历史数据中挖掘客流特征,并提出客流预测方法,为轨道交通运营部门在大型活动期间的行车计划提供科学的决策支持。[方法]从多源影响因素的挖掘与分析出发,收集了起始车站、馆站距离、日期类型、天气类型、活动类型、活动等级、售票规模、出站人数等信息作为特征变量,考虑到随着时间推移可获得的自变量信息数量和精确度越来越高,设计了滚动数据驱动的XGBoost预测模型;基于乘客的出行轨迹,提出了大型活动散场大客流时空分布分析方法。以某城市车站附近场馆举办大型活动为例,验证所提预测方法的准确性。[结果及结论]所提客流预测方法在OD(起讫点)层面、线路层面、进站量层面均取得了较好的预测精度,能够为车站客流管控和网络运营调整提供决策依据。 展开更多
关键词 城市轨道交通 大型活动散场 大客流 时空分布预测
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同源·互文·竞合:社交媒体时代体育赛事议题的传播流布与动员转化 被引量:1
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作者 卢兴 刘鹏宇 《上海体育大学学报》 北大核心 2025年第7期11-22,共12页
高效灵活的社会动员执行是激发大型体育赛事多元价值实现的重要前提。剖析多类型体育赛事动员议题在社会交往中的信息流向及内在规律,建构合理有效的体育赛事动员框架,对于推进我国大型体育赛事价值承载与社会凝聚力的提升具有重要意义... 高效灵活的社会动员执行是激发大型体育赛事多元价值实现的重要前提。剖析多类型体育赛事动员议题在社会交往中的信息流向及内在规律,建构合理有效的体育赛事动员框架,对于推进我国大型体育赛事价值承载与社会凝聚力的提升具有重要意义。选取2021—2023年4项大型综合体育赛事为研究对象,利用复杂网络建模对不同类型议题在传播规模、广度、深度与时序4个维度的网络结构与流布效果进行差异性透视后发现,现阶段国家情感与文化属性议题的水平扩散效果最为显著,竞技属性议题的深化影响效能更加突出,娱乐属性议题的传播效果整体均衡。据此,从动员结构布局的动态性调整、共意动员的适配性引导与理性动员的制宜化调适3个方面探讨我国大型体育赛事社会动员转化的实践路径。 展开更多
关键词 大型体育赛事 复杂网络 社交媒体 传播流布 动员
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基于动态事件触发的混输管道严重段塞流控制
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作者 康朝海 花伟翔 +3 位作者 任伟建 王树峰 张永丰 霍凤财 《吉林大学学报(信息科学版)》 2025年第3期557-564,共8页
针对海底混输水平管-下倾管-立管系统严重段塞流控制中通讯条件受限的问题,提出了一种基于动态事件触发(DET:Dynamic Event Triggering)的模型预测控制(MPC:Model Predictive Control)策略。首先,描述段塞流产生的原因和过程,并分析了... 针对海底混输水平管-下倾管-立管系统严重段塞流控制中通讯条件受限的问题,提出了一种基于动态事件触发(DET:Dynamic Event Triggering)的模型预测控制(MPC:Model Predictive Control)策略。首先,描述段塞流产生的原因和过程,并分析了用于控制的简化模型。其次,设计一种基于预测值与实际值偏差的动态事件触发机制,实时监测系统的运行状态并调节事件触发条件,以提高系统的稳态性能和降低触发频率。最后,进行实验对比分析。结果表明,所提方法在保证控制性能的基础上能有效降低系统触发频率,与小开度阀门相比,石油潜在产量增加了约2.8%。 展开更多
关键词 水平管-下倾管-立管系统 严重段塞流 事件触发 模型预测控制
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陆上洪水型优质砂体形成机理——以兰州窑街地区炭洞沟二号坝洪水沉积为例
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作者 李相博 刘化清 +5 位作者 郝彬 杨占龙 张晶 刘震华 李智勇 李在光 《岩性油气藏》 北大核心 2025年第6期28-34,共7页
通过野外地质考察及实验分析测试,明确了兰州窑街地区炭洞沟泥石流多发地段的洪水沉积特征,并揭示了优质砂体的形成机理。研究结果表明:(1)兰州窑街地区炭洞沟洪水沉积物分为砂砾石(G)、含砾粗砂(C)、中细砂(MS)及含粉细砂泥质沉积(黏土... 通过野外地质考察及实验分析测试,明确了兰州窑街地区炭洞沟泥石流多发地段的洪水沉积特征,并揭示了优质砂体的形成机理。研究结果表明:(1)兰州窑街地区炭洞沟洪水沉积物分为砂砾石(G)、含砾粗砂(C)、中细砂(MS)及含粉细砂泥质沉积(黏土)(FM)4种类型,自上游向下游有序分布,中细砂(MS)在汇水区下游段连续分布,分选良好,为优质砂体。(2)研究区洪水沉积物的有序分布与流体搬运过程中泥石流(非牛顿流体)向牵引流(牛顿流体)转化有关,该转化受区域“V”形拐弯河道及地形坡度变化联合控制;牵引流的机械分异作用及高能洪水颗粒间的碰撞破碎是研究区优质砂体形成的主要原因。 展开更多
关键词 泥石流 牵引流 洪水事件 优质砂体 C-M图 现代沉积 陆相环境
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结合数据流和控制流漂移发现的业务过程异常检测方法
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作者 孙晋永 许乾 +2 位作者 闻立杰 邓文伟 马瑞阳 《计算机集成制造系统》 北大核心 2025年第5期1672-1683,共12页
现有的业务过程异常检测方法不能发现业务过程模型可能发生的数据流漂移,会将合理的数据流漂移案例判定为异常案例,降低了异常检测的准确性。因此,提出一种结合数据流和控制流漂移发现的业务过程异常检测方法。首先,将事件日志中的事件... 现有的业务过程异常检测方法不能发现业务过程模型可能发生的数据流漂移,会将合理的数据流漂移案例判定为异常案例,降低了异常检测的准确性。因此,提出一种结合数据流和控制流漂移发现的业务过程异常检测方法。首先,将事件日志中的事件名(即控制流)与其他事件属性(即数据流)一样看待,使用独热编码对其进行统一编码,得到案例特征数据集。然后,构建事件属性预测模型来获取业务过程实例的下一事件的所有可能发生事件及其属性的概率分布。进一步,将以上概率分布转换为异常评分,得到候选异常案例集。接着,使用基于霍夫丁不等式的双层滑动窗口机制、概念漂移比率从候选异常案例集中识别出数据流、控制流漂移案例,进而得到真正的异常案例。最后,采用循环更新策略,使用得到的漂移案例集作为新知识来更新事件属性预测模型,使得所提出的方法更准确地检测出真正的业务过程异常。仿真实验结果表明,相比现有的业务过程异常检测方法,所提出的方法能够较准确地发现事件日志中的数据流漂移,对于包含数据流和控制流漂移的事件日志可以获得较高的异常检测准确性。 展开更多
关键词 业务过程异常检测 数据流漂移 事件属性 概念漂移比率 模型更新
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