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Gradual Clamping Reduced Ischemia-Reperfusion Injury in an Isolated Rat Heart Model 被引量:2
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作者 Hongbin Feng Hongli Wang +2 位作者 Yang Zhao Zhinan Zheng Sanqing Jin 《World Journal of Cardiovascular Surgery》 2016年第6期79-86,共8页
Objectives: We hypothesized that the organisms and their organs or tissues could adapt themselves to the gradual changes of environment for surviving or reducing damage. This study explored whether gradual clamping (G... Objectives: We hypothesized that the organisms and their organs or tissues could adapt themselves to the gradual changes of environment for surviving or reducing damage. This study explored whether gradual clamping (GC) could reduce myocardial ischemia-reperfusion (IR) injury in rat heart. Methods: Twelve rats were randomized to IR group and GC group, then the hearts were isolated and perfused with Langendorff apparatus. Before cardioplegia, the perfusion was stopped abruptly in IR group while slowly with 5-minute in GC group. The hearts were subjected to 30-minute ischemia and 60-minute reperfusion. The left ventricular develop pressure (LVDP) and systolic pressure (LVSP), the maximal rate of the increase and decrease of left ventricular pressure (+dp/dt<sub>max</sub>, ﹣dp/dt<sub>max</sub>) were measured by polygraph system at different time points. The recovery of the variables was expressed as the ratio of these values at individual time point after reperfusion to the baseline respectively. Results: The recovery of LVDP after reperfusion was better than that in IR group (P = 0.034). No significant difference in the recovery of LVSP, +dp/dtmax and ﹣dp/dt<sub>max</sub> between groups was observed. Conclusions: Gradual clamping could improve the recovery of LVDP after IR, suggesting that gradual clamping could reduce myocardial IR injury. 展开更多
关键词 gradual Clamping Ischemia-Reperfusion Injury gradual Adaptation Rat Heart Model
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英语短语动词的三要素——以away组成的含gradually之义的短语动词为例
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作者 赵静云 《安徽农业大学学报(社会科学版)》 2003年第6期124-128,共5页
从语义的角度来对短语动词进行系统地认知是一种科学的新理念、新方法。以短语动词中的副词或介词为主线来进行纵向的组群亦是切实可行的一种好方法。然后在横向上辨析相关的同义的短语。以三者的有机结合所形成的复合思维来加以认知则... 从语义的角度来对短语动词进行系统地认知是一种科学的新理念、新方法。以短语动词中的副词或介词为主线来进行纵向的组群亦是切实可行的一种好方法。然后在横向上辨析相关的同义的短语。以三者的有机结合所形成的复合思维来加以认知则更具特色。由away组成的短语动词可表数个意义。含“gradually”之义时,所表意义为动状关系。 展开更多
关键词 英语 短语动词 三要素 away gradually 语义认知 纵向组群 动状关系
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Gradual solution heat treatment of AlSiCuMg cast alloys 被引量:13
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作者 WANG Guiqing , BIAN Xiufang ,and ZHANG Junyan1) The Key Laboratory of Liquid Structure and Heredity of Materials, Ministry of Education, Shandong University, Jinan 250061, China2) Department of Material Science and Technology, Shandong Architectural Engineering Institute, Jinan 250014, China 《Rare Metals》 SCIE EI CAS CSCD 2003年第4期304-308,共5页
The microstructure characteristics of AlSiCuMg cast alloys were studied withdifferent Cu content and the gradual solution treatment by DSC, SEM, TEM and mechanical method. Themelting point of alpha (Al) + Si decreases... The microstructure characteristics of AlSiCuMg cast alloys were studied withdifferent Cu content and the gradual solution treatment by DSC, SEM, TEM and mechanical method. Themelting point of alpha (Al) + Si decreases and polynary eutectic phases with low melting point formwith increase of Cu content. Gradual solution treatment includes two steps: solution treating nearthe melting point of polynary eutectic phase to take it dissolve first, and then increasing solutiontemperature to take the remainder copper intermetallics dissolved into alpha (Al). Grain boundariesmelting can be avoided by gradual solution treatment, even the maximum solution temperature isabove final solidification point, and the age hardening response increases correspondingly 展开更多
关键词 aluminum alloy gradual solution heat treatment differential scanningcalorimetry (DSC) polynary eutectic phase
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Improved Plasticity and Cold-rolling Workability of Fe–6.5wt%Si Alloy by Warm-rolling with Gradually Decreasing Temperature 被引量:4
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作者 Yuanke Mo Zhihao Zhang +1 位作者 Hongjiang Pan Jianxin Xie 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2016年第5期477-484,共8页
The effects of warm-rolling process on the microstructure, ordering, mechanical properties and cold- rolling workability of Fe-6.Swt%Si alloy were investigated, where three processes of warm-rolling with the same tota... The effects of warm-rolling process on the microstructure, ordering, mechanical properties and cold- rolling workability of Fe-6.Swt%Si alloy were investigated, where three processes of warm-rolling with the same total reduction of 93% were used, including (1) 500 ℃/12 passes/total reduction of 93%, (2) 500 ℃13 passes/total reduction of 50% + 400 ℃19 passes/total reduction of 86%, and (3) 500 ℃13 passes/total reduction of 50% + 400 ℃15 passes/total reduction of 60% + 300 ℃14 passes/total reduction of 64%. The results show that compared with process (1) warm-rolling with constant temperature of 500 ℃, process (2) and process (3) warm-rolling with gradually decreasing temperature can significantly improve the room temperature plasticity and cold-rolling workability of the Fe-6.5wt%Si alloy. For example, the three point bending fracture deflections are increased by 54.5% and 81.8% for processes (2) and (3), respectively, and the maximum reductions of single pass cold-rolling without edge crack are increased from 50% of process (1) to 55% of process (2) and 62% of process (3), respectively. The plasticity improvement of the Fe- 6.5wt%Si alloy can be attributed to both reductions of surface oxidation degree and order degree of the alloy by warm-rolling with gradually decreasing temperature. 展开更多
关键词 Fe–6.5wt%Si alloy Warm-rolling gradually decreasing temperature Ordering Mechanical property
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ANALYSIS MODEL ON GRADUAL CHANGE PRINCIPLE OF EFFECT ZONES OF LAYER FACE FOR ROLLED CONTROL CONCRETE DAM 被引量:1
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作者 顾冲时 宋敬衖 方海挺 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2006年第11期1523-1529,共7页
The effect zones of layer face for RCC (rolled control concrete) dam have gradual change characteristics. Based on the analysis thought of complex material, a model was built to analyze above principle of RCC dam by... The effect zones of layer face for RCC (rolled control concrete) dam have gradual change characteristics. Based on the analysis thought of complex material, a model was built to analyze above principle of RCC dam by use of series-wound and shunt-wound connection. Some methods were proposed to determine the instantaneous Young's modulus, delayed Young's modulus and viscosity coefficient of effect zones of layer face. Above models and methods were used to mine the principle of gradual change of key calculation parameters which can response the characteristics of effect zones. The principle of gradual change was described. A model was established to analyze the threedimensional viscoelastic problem of RCC dam. Above programs were developed. The examples show that the proposed models and methods to determine the key calculation parameters of effect zones can reflect the status of RCC dam accurately. 展开更多
关键词 (rolled control concrete dam) effect zones calculation parameter principle of gradual change viscoelastic model
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A gradually descent method for discrete global optimization 被引量:1
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作者 杨永建 张连生 《Journal of Shanghai University(English Edition)》 CAS 2007年第1期39-44,共6页
In this paper, a new method named as the gradually descent method was proposed to solve the discrete global optimization problem. With the aid of an auxiliary function, this method enables to convert the problem of fi... In this paper, a new method named as the gradually descent method was proposed to solve the discrete global optimization problem. With the aid of an auxiliary function, this method enables to convert the problem of finding one discrete minimizer of the objective function f to that of finding another at each cycle. The auxiliary function can ensure that a point, except a prescribed point, is not its integer stationary point if the value of objective function at the point is greater than the scalar which is chosen properly. This property leads to a better minimizer of f found more easily by some classical local search methods. The computational results show that this algorithm is quite efficient and reliable for solving nonlinear integer programming problems. 展开更多
关键词 gradually descent method nonlinear integer programming integer programming ALGORITHM
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The gradual subduction-collision evolution model of Proto-South China Sea and its control on oil and gas 被引量:1
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作者 Xiaojun Xie Wu Tang +5 位作者 Gongcheng Zhang Zhigang Zhao Shuang Song Shixiang Liu Yibo Wang Jia Guo 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2023年第3期123-137,共15页
This study involved outcrop,drilling,seismic,gravity,and magnetic data to systematically document the geological records of the subduction process of Proto-South China Sea(PSCS)and establish its evolution model.The re... This study involved outcrop,drilling,seismic,gravity,and magnetic data to systematically document the geological records of the subduction process of Proto-South China Sea(PSCS)and establish its evolution model.The results indicate that a series of arc-shaped ophiolite belts and calcalkaline magmatic rocks are developed in northern Borneo,both of which have the characteristics of gradually changing younger from west to east,and are direct signs of subduction and collision of PSCS.At the same time,the subduction of PSCS led to the formation of three accretion zones from the south to the north in Borneo,the Kuching belt,Sibu belt,and Miri belt.The sedimentary formation of northern Borneo is characterized by a three-layer structure,with the oceanic basement at the bottom,overlying the deep-sea flysch deposits of the Rajang–Crocker group,and the molasse sedimentary sequence that is dominated by river-delta and shallow marine facies at the top,recording the whole subduction–collision–orogeny process of PSCS.Further,seismic reflection and tomography also confirmed the subduction and collision of PSCS.Based on the geological records of the subduction and collision of PSCS,combined with the comprehensive analysis of segmented expansion and key tectonic events in the South China Sea,we establish the“gradual”subduction-collision evolution model of PSCS.During the late Eocene to middle Miocene,the Zengmu,Nansha,and Liyue–Palawan blocks were separated by West Baram Line and Balabac Fault,which collided with the Borneo block and Kagayan Ridge successively from the west to the east,forming several foreland basin systems,and PSCS subducted and closed from the west to the east.The subduction and extinction of PSCS controlled the oil and gas distribution pattern of southern South China Sea(SSCS)mainly in three aspects.First,the“gradual”closure process of PSCS led to the continuous development of many large deltas in SSCS.Second,the deltas formed during the subduction–collision of PSCS controlled the development of source rocks in the basins of SSCS.Macroscopically,the distribution and scale of deltas controlled the distribution and scale of source rocks,forming two types of source rocks,namely,coal measures and terrestrial marine facies.Microscopically,the difference of terrestrial higher plants carried by the delta controlled the proportion of macerals of source rocks.Third,the difference of source rocks mainly controlled the distribution pattern of oil and gas in SSCS.Meanwhile,the difference in the scale of source rocks mainly controlled the difference in the amount of oil and gas discoveries,resulting in a huge amount of oil and gas discoveries in the basin of SSCS.Meanwhile,the difference of macerals of source rocks mainly controlled the difference of oil and gas generation,forming the oil and gas distribution pattern of“nearshore oil and far-shore gas”. 展开更多
关键词 Proto-South China Sea gradual subduction-collision evolution model oil and gas distribution southern South China Sea BORNEO
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Gradual Band Energy to Passivate the Window Layer in Solar Cells
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作者 A. Amine M. Bouabdellaoui +2 位作者 K. Zaz Y. Mir M. Zazoui 《Smart Grid and Renewable Energy》 2017年第1期46-51,共6页
The passivation layers at the front of the cell are often referred as to the window layer because it must be transparent so as the solar cell has a high efficiency. In this work, numerical simulation has been proposed... The passivation layers at the front of the cell are often referred as to the window layer because it must be transparent so as the solar cell has a high efficiency. In this work, numerical simulation has been proposed to study the effect of the AlGaAs gradual and normal windows on the cell sensitivity to the electron irradiation so as to passivate the solar cell. To expect the effect of gradual window layers, the J-V and P-V characteristics are confirmed better energy conversion performance of the illuminated solar cells after irradiation. The short circuit current Jsc and the open circuit voltage Voc are evaluated for different electron irradiation fluencies. The results show how the gradual window layer improves resistance to electron irradiation through its own parameters. 展开更多
关键词 gradual WINDOW ELECTRIC Field DEGRADATION SOLAR Cell
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Gradual Bedside Reduction of Gastroschisis in a Resource Constrained Setting: Preliminary Results from 32 Cases
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作者 Nyanit Bob Dorcas Ntsobé Eric Tobie +9 位作者 Ndikontar Raymond Kouna Tsala Irène Nadine Ndongo René Bougoue Takou Horline Vougmo Clémence Kana Serges Paule Ngayap Guy Owono Etoundi Paul Essiene Agnès Steyaert Henri 《Open Journal of Pediatrics》 2023年第5期669-675,共7页
Introduction: Gastroschisis is one of the neonatal pathologies with bad prognosis in developing countries due to a lack of equipment. We aim to report one way of managing this malformation that could be practised ever... Introduction: Gastroschisis is one of the neonatal pathologies with bad prognosis in developing countries due to a lack of equipment. We aim to report one way of managing this malformation that could be practised everywhere, constituting an alternative approach to surgery in poor areas. Patients and Methods: This observational and descriptive study included newborn babies with gastroschisis who underwent gradual bedside reduction at the Paediatric Surgery Department of the Yaounde Central Hospital. Results: Our cohort was constituted by 32 newborn babies with a mean age of 18.12 hours on admission. The Lefort type 2 was the most frequent in 81.25% of cases. The mean time for oral feeding after complete reduction was 17.4 days and the duration of hospital stay was 24.91 days. Survival rates were at 40.63%, with a residual hernia after healing in 38.46% of cases. Conclusion: Despite the high rate of mortality, gradual reduction of gastroschisis at the bedside seems to be an opportunity for resource constrained areas and can be an alternative solution to surgery. 展开更多
关键词 GASTROSCHISIS Lefort Type 2 gradual Reduction Limited Resources
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China's Science Gradually Strengthened
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作者 Shangguan Yun 《China's Foreign Trade》 1995年第11期9-9,共1页
In order to ensure the steady development of our science, the Chinese government has continuously increased input in the last ten years. Information from the State Statistics Bureau shows that by the end of 1994, the ... In order to ensure the steady development of our science, the Chinese government has continuously increased input in the last ten years. Information from the State Statistics Bureau shows that by the end of 1994, the national institutions and enterprises boasted 18.659 million technical experts, 4.3 times the number in 1978, or 1258 technical experts every ten thousand people, redoubling that of 1978. The whole country has 5860 independent scientific research and development (R & D) institutions, 展开更多
关键词 HIGH China’s Science gradually Strengthened
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Effects of Gradual Water Deficit Stress on Phenological and Morphological Traits in Chickpea (Cicer arietinum L.)
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作者 N. Niari Khamssi K. Ghassemi Golezani +1 位作者 S. Zehtab A. Najaphy 《Journal of Agricultural Science and Technology》 2010年第5期95-100,共6页
The aims of this study were to investigate the effect of gradual water deficit stress on some phonological and morphological traits and grain yield of desi and kabuli chickpea cultivars. This study was carried out in ... The aims of this study were to investigate the effect of gradual water deficit stress on some phonological and morphological traits and grain yield of desi and kabuli chickpea cultivars. This study was carried out in 2007 and 2008, to evaluate responses of three chickpea cultivars (Hashem and Arman from kabuli and Pirooz from desi type) under well watering (I1: 70mm evaporation from class A pan), gradual water deficit (12 and 13: 70→90→ 110→130 and 70→100→130mm evaporation from class A pan, respectively) and severe water stress (14: 130mm evaporation from class A pan). Result showed that days to flowering and plant height were decreased, as water limitation increased. This reduction was significant under gradual water stress (I2 and I3) and Severe water deficit (I4), compared with control (I1). There were no significant differences in grain filling period and grain yield among I~, I2 and I3 irrigation treatments. No significant differences in days to physiologic maturity and number of sub branches were recorded among irrigation treatments. Interactions of year×cultivar for days to physiologic maturity, grain filling period and grain yield (P≤0.01) and for days to flowering and plant height (P≤0.05) were significant. The superiority of Arman in producing comparatively greater grain yield could be attributed to higher grain filling period of this cultivar in both years. 展开更多
关键词 CHICKPEA gradual water deficit grain filling period grain yield physiologic maturity.
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On the Gradualness by the Narrative Ambiguity in The Sound and The Fury 被引量:1
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作者 Tian Ping Hong Zengliu 《学术界》 CSSCI 北大核心 2012年第11期253-262,共10页
How to disambiguate the four narrators'narratives is the critical step to understand the whole work of The Sound and The Fury. With the gradualness produced by the ambiguous narrators'narration of juxtapositio... How to disambiguate the four narrators'narratives is the critical step to understand the whole work of The Sound and The Fury. With the gradualness produced by the ambiguous narrators'narration of juxtaposition of modern and traditional narration,another synchronized gradualness of Caddy is discovered,too. On the basis of deconstruction and psycho - analyses,rich and deep significance is illustrated by elucidation of narrative gradualness,as a new way to disambiguate the narrators'narration. 展开更多
关键词 歧义 骚动 渐进性
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Verification on Gradual Escalation Phenomenon of Violation Behavior Using an Experimental Paradigm for Risk Diversification
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作者 Atsuo Murata 《Psychology Research》 2015年第3期197-204,共8页
关键词 违法违规行为 风险评估 分散 验证 不道德行为 冒险行为 安全规则 实验
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Multi-task gradual inference with a single encoder–decoder network for automatic portrait matting
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作者 Wenbing Yang Wei Ma +1 位作者 Qing Mi Hongbin Zha 《Computational Visual Media》 2025年第6期1385-1398,共14页
This paper presents a multi-task gradual inference model,MTGINet,for automatic portrait matting.It handles the subtasks of automatic portrait matting,namely portrait–transition–background trimap segmentation and tra... This paper presents a multi-task gradual inference model,MTGINet,for automatic portrait matting.It handles the subtasks of automatic portrait matting,namely portrait–transition–background trimap segmentation and transition region matting,with a single encoder–decoder structure.First,we enrich the highest stage of features from the encoder with portrait shape context via a shape context aggregation(SCA)module for trimap segmentation.Then,we fuse the SCA-enhanced features with detailed clues from the encoder for transition-region-aware alpha matting.The gradual inference model naturally allows sufficient interaction between the subtasks via forward computation and backwards propagation during training,and therefore achieves high accuracy while maintaining low complexity.In addition,considering the discrepancies in feature requirements across subtasks,we adapt the features from the encoders before reusing them via a feature rectification module.In addition to the MTGINet model,we have constructed a new large-scale dataset,HPM-17K,for half-body portrait matting.It consists of 16,967 images with diverse backgrounds.Comparative experiments with existing deep models on the public P3M-10K dataset and our HPM-17K dataset demonstrate that the proposed model exhibits state-of-the-art performance. 展开更多
关键词 portrait matting alpha matting multi-task gradual inference background replacement encoder-decoder network
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低碳转型冲击与中国城市经济韧性——基于低碳城市试点的准自然实验
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作者 周杰琦 杨胤豪 崔传涛 《贵州财经大学学报》 北大核心 2026年第1期133-142,共10页
低碳城市试点作为兼顾减碳承诺和可持续发展的环境规制工具,在实现节能减排的同时是否可能造成经济社会系统性变革,进而冲击城市韧性水平?既有研究对能否在保证经济韧性前提下推动碳减排尚还未有确切答案。文章以低碳城市试点为准自然实... 低碳城市试点作为兼顾减碳承诺和可持续发展的环境规制工具,在实现节能减排的同时是否可能造成经济社会系统性变革,进而冲击城市韧性水平?既有研究对能否在保证经济韧性前提下推动碳减排尚还未有确切答案。文章以低碳城市试点为准自然实验,剖析低碳转型影响城市经济韧性的机制与异质性,采用渐进双重差分法进行理论命题的实证检验。研究发现:(1)低碳城市试点总体上增强城市经济韧性,但该效应呈先抑制后促进的动态特征,这一作用主要源于抵抗力和适应力子系统先抑制后促进的时变特征,而恢复力子系统呈现逐渐增强态势;(2)机制检验显示,试点政策通过推动产业清洁转型、低碳交通发展、人力资本流入和居民绿色消费增强城市经济韧性;(3)异质性分析发现,试点政策对经济韧性的提升作用在经济集聚程度更高、营商环境更优、要素市场扭曲程度更低的城市更为明显;(4)基于微观就业视角的经济韧性评估发现,试点政策在造成污染企业“棕色失业”的同时也增加清洁企业“绿色就业”,最终在城市层面产生就业创造的溢出效应,低碳转型在经济韧性维度的收益仍大于成本。文章从环境政策视角深化对经济韧性动因的理解,为在“双碳”目标刚性约束下防范化解重大风险和推动高质量发展提供有益启示。 展开更多
关键词 低碳城市试点 城市经济韧性 渐进双重差分模型
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DriftXMiner: A Resilient Process Intelligence Approach for Safe and Transparent Detection of Incremental Concept Drift in Process Mining
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作者 Puneetha B.H Manoj Kumar M.V +1 位作者 Prashanth B.S. Piyush Kumar Pareek 《Computers, Materials & Continua》 2026年第1期1086-1118,共33页
Processes supported by process-aware information systems are subject to continuous and often subtle changes due to evolving operational,organizational,or regulatory factors.These changes,referred to as incremental con... Processes supported by process-aware information systems are subject to continuous and often subtle changes due to evolving operational,organizational,or regulatory factors.These changes,referred to as incremental concept drift,gradually alter the behavior or structure of processes,making their detection and localization a challenging task.Traditional process mining techniques frequently assume process stationarity and are limited in their ability to detect such drift,particularly from a control-flow perspective.The objective of this research is to develop an interpretable and robust framework capable of detecting and localizing incremental concept drift in event logs,with a specific emphasis on the structural evolution of control-flow semantics in processes.We propose DriftXMiner,a control-flow-aware hybrid framework that combines statistical,machine learning,and process model analysis techniques.The approach comprises three key components:(1)Cumulative Drift Scanner that tracks directional statistical deviations to detect early drift signals;(2)a Temporal Clustering and Drift-Aware Forest Ensemble(DAFE)to capture distributional and classification-level changes in process behavior;and(3)Petri net-based process model reconstruction,which enables the precise localization of structural drift using transition deviation metrics and replay fitness scores.Experimental validation on the BPI Challenge 2017 event log demonstrates that DriftXMiner effectively identifies and localizes gradual and incremental process drift over time.The framework achieves a detection accuracy of 92.5%,a localization precision of 90.3%,and an F1-score of 0.91,outperforming competitive baselines such as CUSUM+Histograms and ADWIN+Alpha Miner.Visual analyses further confirm that identified drift points align with transitions in control-flow models and behavioral cluster structures.DriftXMiner offers a novel and interpretable solution for incremental concept drift detection and localization in dynamic,process-aware systems.By integrating statistical signal accumulation,temporal behavior profiling,and structural process mining,the framework enables finegrained drift explanation and supports adaptive process intelligence in evolving environments.Its modular architecture supports extension to streaming data and real-time monitoring contexts. 展开更多
关键词 Process mining concept drift gradual drift incremental drift clustering ensemble techniques process model event log
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Experimental study of the flow structure of decelerating and accelerating flows under a gradually varying flume 被引量:3
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作者 王协康 易子靖 +2 位作者 闫旭峰 黄尔 刘兴年 《Journal of Hydrodynamics》 SCIE EI CSCD 2015年第3期340-349,共10页
The turbulence characteristics of both decelerating and accelerating flows under a gradually varying flume are investigated by using a three-dimensional down-looking acoustic Doppler velocimeter (ADV). The time-aver... The turbulence characteristics of both decelerating and accelerating flows under a gradually varying flume are investigated by using a three-dimensional down-looking acoustic Doppler velocimeter (ADV). The time-averaged velocity profiles are flatened except for the central parts, and fairly fit into logarithmic laws and those in the plane circulation under the gradual expansion are more likely to be negative. The complex secondary currents are identified under the present gradual transition attributed to the combination of driving forces induced by both the boundary configuration variation and the tmbalanced turbulence: a circulation on each side of the expansion and a pair of circulations on each side of the contraction. One sees an anisotropy in the turbulence intensities, the turbulence intensities increase or level out with the flow depth except those under expansion, and the V component of the turbulence intensity typically outweighs that in the streamwise direction. Apart from the above results, the respective particular distributions of the primary Reynolds shear stresses ( rxy and rxz ) under the gradual expansion and contraction can account for the patterns of the secondary currents in this investigation. 展开更多
关键词 turbulence characteristics secondary currents gradual transition non-uniform flows open channel
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Search recommendation model based on user search behavior and gradual forgetting collaborative filtering strategy 被引量:3
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作者 LIU Chuan-chang 《The Journal of China Universities of Posts and Telecommunications》 EI CSCD 2010年第3期110-117,共8页
The existing search engines are lack of the consideration of personalization and display the same search results for different users despite their differences in interesting and purpose.By analyzing user's dynamic... The existing search engines are lack of the consideration of personalization and display the same search results for different users despite their differences in interesting and purpose.By analyzing user's dynamic search behavior,the paper introduces a new method of using a keyword query graph to express user's dynamic search behavior,and uses Bayesian network to construct the prior probability of keyword selection and the migration probability between keywords for each user.To reflect the dynamic changes of the user's preference,the paper introduces non-lineal gradual forgetting collaborative filtering strategy into the personalized search recommendation model.By calculating the similarity between each two users,the model can do the recommendation based on neighbors and be used to construct the personalized search engine. 展开更多
关键词 search recommendation model search behavior expression keyword query graph gradual forgetting collaborative filtering
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A 0.75 dB NF LNA in GaAs pHEMT utilizing gate–drain capacitance and gradual inductor 被引量:1
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作者 王硕 郑新年 +1 位作者 杨浩 张海英 《Journal of Semiconductors》 EI CAS CSCD 2015年第7期108-113,共6页
A two-stage monolithic microwave integrated circuit (MMIC) low noise amplifier (LNA) fabricated in 0.5 μm GaAs pHEMT is presented. The Miller effect introduced by the parasitic gate-drain capacitance is utilized ... A two-stage monolithic microwave integrated circuit (MMIC) low noise amplifier (LNA) fabricated in 0.5 μm GaAs pHEMT is presented. The Miller effect introduced by the parasitic gate-drain capacitance is utilized to decrease the value of the input inductor. Additionally, the input on-chip inductor is a novel high Q gradual structure. The noise figure is reduced with these two methods. With good input and output matching, the LNA achieves a noise figure of 0.75 dB and a small signal gain of 32.7 dB over 698-806 MHz. The input 1 dB compression point is -21.8 dBm and the input third order interception point is -10 dBm. 展开更多
关键词 LNA PHEMT Miller effect gradual inductor
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Improvement of blue InGaN light-emitting diodes with gradually increased barrier heights from n- to p-layers 被引量:1
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作者 Wu TIAN Xiong HUI Yang LI Jiangnan DAI Yanyan FANG Zhihao WU Changqing CHEN 《Frontiers of Optoelectronics》 EI CSCD 2013年第4期429-434,共6页
The advantages of blue InGaN light-emitting diodes (LED) with the active region of gradually increased barrier heights from n- to p-layers are studied. The energy band diagram, hole concentration, electrostatic fiel... The advantages of blue InGaN light-emitting diodes (LED) with the active region of gradually increased barrier heights from n- to p-layers are studied. The energy band diagram, hole concentration, electrostatic field near the electron blocking layer (EBL), and the internal quantum efficiency (IQE) are investigated by Crosslight simulation program. The simulation results show that the structure with gradually increased barrier heights has better performance over the equal one, which can be attributed to the mitigated polarization effect near the interface of the last barrier/EBL due to less interface polarization charges. Moreover, reduced barrier height toward the n-layers is beneficial for holes injection and transportation in the active region. As a result, holes are injected into the active region more efficiently and distributed uniformly in the quantum wells, with which both the IQE and the total lighting power are increased. Although it can lead to the broadening of the spontaneous emission spectrum, the increase is slight such that it has little effect on the application in solid-state lighting. 展开更多
关键词 INGAN light-emitting diodes (LED) polariza-tion effect gradual barrier height
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