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Bayesian partial pooling to reduce uncertainty in overcoring rock stress estimation
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作者 Yu Feng Ke Gao Suzanne Lacasse 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第4期1192-1201,共10页
The state of in situ stress is a crucial parameter in subsurface engineering,especially for critical projects like nuclear waste repository.As one of the two ISRM suggested methods,the overcoring(OC)method is widely u... The state of in situ stress is a crucial parameter in subsurface engineering,especially for critical projects like nuclear waste repository.As one of the two ISRM suggested methods,the overcoring(OC)method is widely used to estimate the full stress tensors in rocks by independent regression analysis of the data from each OC test.However,such customary independent analysis of individual OC tests,known as no pooling,is liable to yield unreliable test-specific stress estimates due to various uncertainty sources involved in the OC method.To address this problem,a practical and no-cost solution is considered by incorporating into OC data analysis additional information implied within adjacent OC tests,which are usually available in OC measurement campaigns.Hence,this paper presents a Bayesian partial pooling(hierarchical)model for combined analysis of adjacent OC tests.We performed five case studies using OC test data made at a nuclear waste repository research site of Sweden.The results demonstrate that partial pooling of adjacent OC tests indeed allows borrowing of information across adjacent tests,and yields improved stress tensor estimates with reduced uncertainties simultaneously for all individual tests than they are independently analysed as no pooling,particularly for those unreliable no pooling stress estimates.A further model comparison shows that the partial pooling model also gives better predictive performance,and thus confirms that the information borrowed across adjacent OC tests is relevant and effective. 展开更多
关键词 Overcoring stress measurement Uncertainty reduction Partial pooling Bayesian hierarchical model Nuclear waste repository
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A Pooling Method Developed for Use in Convolutional Neural Networks
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作者 Ìsmail Akgül 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第10期751-770,共20页
In convolutional neural networks,pooling methods are used to reduce both the size of the data and the number of parameters after the convolution of the models.These methods reduce the computational amount of convoluti... In convolutional neural networks,pooling methods are used to reduce both the size of the data and the number of parameters after the convolution of the models.These methods reduce the computational amount of convolutional neural networks,making the neural network more efficient.Maximum pooling,average pooling,and minimum pooling methods are generally used in convolutional neural networks.However,these pooling methods are not suitable for all datasets used in neural network applications.In this study,a new pooling approach to the literature is proposed to increase the efficiency and success rates of convolutional neural networks.This method,which we call MAM(Maximum Average Minimum)pooling,is more interactive than other traditional maximum pooling,average pooling,and minimum pooling methods and reduces data loss by calculating the more appropriate pixel value.The proposed MAM pooling method increases the performance of the neural network by calculating the optimal value during the training of convolutional neural networks.To determine the success accuracy of the proposed MAM pooling method and compare it with other traditional pooling methods,training was carried out on the LeNet-5 model using CIFAR-10,CIFAR-100,and MNIST datasets.According to the results obtained,the proposed MAM pooling method performed better than the maximum pooling,average pooling,and minimum pooling methods in all pool sizes on three different datasets. 展开更多
关键词 pooling convolutional neural networks deep learning
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U-Net Based Dual-Pooling Segmentation of Bone Metastases in Thoracic SPECT Bone Scintigrams
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作者 Yang He Qiang Lin +1 位作者 Yongchun Cao Zhengxing Man 《Journal of Computer and Communications》 2024年第4期60-71,共12页
In order to enhance the performance of the CNN-based segmentation models for bone metastases, this study proposes a segmentation method that integrates dual-pooling, DAC, and RMP modules. The network consists of disti... In order to enhance the performance of the CNN-based segmentation models for bone metastases, this study proposes a segmentation method that integrates dual-pooling, DAC, and RMP modules. The network consists of distinct feature encoding and decoding stages, with dual-pooling modules employed in encoding stages to maintain the background information needed for bone scintigrams diagnosis. Both the DAC and RMP modules are utilized in the bottleneck layer to address the multi-scale problem of metastatic lesions. Experimental evaluations on 306 clinical SPECT data have demonstrated that the proposed method showcases a substantial improvement in both DSC and Recall scores by 3.28% and 6.55% compared the baseline. Exhaustive case studies illustrate the superiority of the methodology. 展开更多
关键词 Tumor Bone Metastasis Bone Scintigram Lesion Segmentation CNN Dual pooling
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基于改进Faster R-CNN的热轧带钢表面缺陷检测
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作者 邓慧 曾磊 《控制工程》 CSCD 北大核心 2024年第4期752-759,共8页
热轧带钢是钢铁行业的重要产品,其表面缺陷是影响产品质量的重要因素。针对传统缺陷检测算法存在的过程繁琐、精度不足和效率低下等问题,提出一种基于改进更快速区域卷积神经网络(faster region-based convolutional neural network,Fas... 热轧带钢是钢铁行业的重要产品,其表面缺陷是影响产品质量的重要因素。针对传统缺陷检测算法存在的过程繁琐、精度不足和效率低下等问题,提出一种基于改进更快速区域卷积神经网络(faster region-based convolutional neural network,Faster R-CNN)的检测算法,实现对热轧带钢表面缺陷的高效、高精度检测。首先,采用特征相加的方法对底层细节特征和高层语义特征进行融合;然后,采用精准的感兴趣区域池化(precise region of interest pooling,Precise ROI Pooling)获取固定大小的特征向量,避免特征出现位置偏差;最后,利用均值偏移聚类算法对带钢数据集进行聚类,获得适用于热轧带钢表面缺陷检测的先验框尺寸。实验结果表明,所提算法在热轧带钢表面缺陷检测数据集上的平均精度均值达到了85.34%,检测速度为23.5帧/s,且鲁棒性良好,满足实际的工业检测需求。 展开更多
关键词 表面缺陷检测 Faster R-CNN 特征融合 Precise ROI pooling 均值偏移
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辛空间的排列问题及具有容错能力的pooling设计的紧界 被引量:9
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作者 赵向会 李莉 张更生 《数学物理学报(A辑)》 CSCD 北大核心 2012年第2期414-423,共10页
该文利用辛空间上的子空间构造了一类新的d^z析取矩阵,然后研究了如下排列问题:对于给定的整数m,r,s,v,d,q和辛空间F_q^(2v)中的一个(m,s)型子空间S,这里v+s≥m>r≥2s-1≥1,d≥2,q是一个素数的幂,作者从S中找到d个(m-1,s-1)型子空间H... 该文利用辛空间上的子空间构造了一类新的d^z析取矩阵,然后研究了如下排列问题:对于给定的整数m,r,s,v,d,q和辛空间F_q^(2v)中的一个(m,s)型子空间S,这里v+s≥m>r≥2s-1≥1,d≥2,q是一个素数的幂,作者从S中找到d个(m-1,s-1)型子空间H_1,…H_d,使包含在这些(m-1,s-1)型子空间中的(r,s-1)型子空间个数达到最大.然后利用这个排列的有关结论,给出了一类pooling设计的紧界. 展开更多
关键词 pooling设计 d^z析取 辛空间 排列问题 紧界
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基于DNA pooling技术的全基因组关联研究筛选主动脉夹层等位基因遗传位点 被引量:1
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作者 陈逸飞 钟诗龙 +3 位作者 罗建方 薛凌 黎明 胡孜阳 《实用医学杂志》 CAS 北大核心 2012年第20期3405-3407,共3页
目的:筛选与主动脉夹层发病机制相关的遗传易感基因。方法:从主动脉夹层患者(150例)及对照组(250例)外周血白细胞提取基因组DNA,采用DNA Pooling为基础的Illumina Human660W-Quad芯片扫描,筛选与主动脉夹层发病相关的遗传易感基因。结果... 目的:筛选与主动脉夹层发病机制相关的遗传易感基因。方法:从主动脉夹层患者(150例)及对照组(250例)外周血白细胞提取基因组DNA,采用DNA Pooling为基础的Illumina Human660W-Quad芯片扫描,筛选与主动脉夹层发病相关的遗传易感基因。结果:(1)对照组女性数量明显多于病例组(P<0.01);年龄、吸烟、高血压、糖尿病人数无统计学差异(P>0.05)。(2)遗传变异位点SNPrs2298491(位于TBCEL基因),SNP rs6080720(位于BFSP1基因),SNP rs7653410(位于SNTN基因),SNP rs2345106(位于COLQ基因)和位于ABCA13基因上的SNPrs4024044可能与主动脉夹层的发病有关。结论:SNPsrs2298491,rs6080720,rs7653410,rs2345106和rs4024044可能是主动脉夹层发病机制相关遗传变异位点的一部分。 展开更多
关键词 主动脉夹层 DNA pooling 单核苷酸多态性 全基因组关联研究 基因
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利用伪辛子空间构造的一类pooling设计及其纠错能力的紧界分析 被引量:1
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作者 赵向会 刘铭 张更生 《河北师范大学学报(自然科学版)》 CAS 2015年第5期369-373,共5页
利用伪辛空间上的子空间构造了一类新的dz-析取矩阵,证明了它的析取性,讨论了反映dz-析取矩阵纠错能力z值的紧界.
关键词 pooling设计 dz-析取 伪辛空间 紧界
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奇特征正交空间上可检错Pooling设计的构作 被引量:1
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作者 赵燕冰 刘志刚 《湖南理工学院学报(自然科学版)》 CAS 2009年第3期16-18,共3页
Pooling设计的数学模型是一个d-disjunct矩阵.利用奇特征正交空间中全迷向子空间构作了d-disjunct矩阵,并通过计算它的Hamming距离分析了它的检纠错能力,根据Kautz-Singleton定理对d的范围作了估算.
关键词 奇特征正交空间 全迷向子空间 pooling设计 D-DISJUNCT矩阵 HAMMING距离 检错 纠错
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NFHP-RN:AMethod of Few-Shot Network Attack Detection Based on the Network Flow Holographic Picture-ResNet
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作者 Tao Yi Xingshu Chen +2 位作者 Mingdong Yang Qindong Li Yi Zhu 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第7期929-955,共27页
Due to the rapid evolution of Advanced Persistent Threats(APTs)attacks,the emergence of new and rare attack samples,and even those never seen before,make it challenging for traditional rule-based detection methods to ... Due to the rapid evolution of Advanced Persistent Threats(APTs)attacks,the emergence of new and rare attack samples,and even those never seen before,make it challenging for traditional rule-based detection methods to extract universal rules for effective detection.With the progress in techniques such as transfer learning and meta-learning,few-shot network attack detection has progressed.However,challenges in few-shot network attack detection arise from the inability of time sequence flow features to adapt to the fixed length input requirement of deep learning,difficulties in capturing rich information from original flow in the case of insufficient samples,and the challenge of high-level abstract representation.To address these challenges,a few-shot network attack detection based on NFHP(Network Flow Holographic Picture)-RN(ResNet)is proposed.Specifically,leveraging inherent properties of images such as translation invariance,rotation invariance,scale invariance,and illumination invariance,network attack traffic features and contextual relationships are intuitively represented in NFHP.In addition,an improved RN network model is employed for high-level abstract feature extraction,ensuring that the extracted high-level abstract features maintain the detailed characteristics of the original traffic behavior,regardless of changes in background traffic.Finally,a meta-learning model based on the self-attention mechanism is constructed,achieving the detection of novel APT few-shot network attacks through the empirical generalization of high-level abstract feature representations of known-class network attack behaviors.Experimental results demonstrate that the proposed method can learn high-level abstract features of network attacks across different traffic detail granularities.Comparedwith state-of-the-artmethods,it achieves favorable accuracy,precision,recall,and F1 scores for the identification of unknown-class network attacks through cross-validation onmultiple datasets. 展开更多
关键词 APT attacks spatial pyramid pooling NFHP(network flow holo-graphic picture) ResNet self-attention mechanism META-LEARNING
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An adaptive physics-informed deep learning method for pore pressure prediction using seismic data
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作者 Xin Zhang Yun-Hu Lu +2 位作者 Yan Jin Mian Chen Bo Zhou 《Petroleum Science》 SCIE EI CAS CSCD 2024年第2期885-902,共18页
Accurate prediction of formation pore pressure is essential to predict fluid flow and manage hydrocarbon production in petroleum engineering.Recent deep learning technique has been receiving more interest due to the g... Accurate prediction of formation pore pressure is essential to predict fluid flow and manage hydrocarbon production in petroleum engineering.Recent deep learning technique has been receiving more interest due to the great potential to deal with pore pressure prediction.However,most of the traditional deep learning models are less efficient to address generalization problems.To fill this technical gap,in this work,we developed a new adaptive physics-informed deep learning model with high generalization capability to predict pore pressure values directly from seismic data.Specifically,the new model,named CGP-NN,consists of a novel parametric features extraction approach(1DCPP),a stacked multilayer gated recurrent model(multilayer GRU),and an adaptive physics-informed loss function.Through machine training,the developed model can automatically select the optimal physical model to constrain the results for each pore pressure prediction.The CGP-NN model has the best generalization when the physicsrelated metricλ=0.5.A hybrid approach combining Eaton and Bowers methods is also proposed to build machine-learnable labels for solving the problem of few labels.To validate the developed model and methodology,a case study on a complex reservoir in Tarim Basin was further performed to demonstrate the high accuracy on the pore pressure prediction of new wells along with the strong generalization ability.The adaptive physics-informed deep learning approach presented here has potential application in the prediction of pore pressures coupled with multiple genesis mechanisms using seismic data. 展开更多
关键词 Pore pressure prediction Seismic data 1D convolution pyramid pooling Adaptive physics-informed loss function High generalization capability
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An Intelligent Framework for Resilience Recovery of FANETs with Spatio-Temporal Aggregation and Multi-Head Attention Mechanism
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作者 Zhijun Guo Yun Sun +2 位作者 YingWang Chaoqi Fu Jilong Zhong 《Computers, Materials & Continua》 SCIE EI 2024年第5期2375-2398,共24页
Due to the time-varying topology and possible disturbances in a conflict environment,it is still challenging to maintain the mission performance of flying Ad hoc networks(FANET),which limits the application of Unmanne... Due to the time-varying topology and possible disturbances in a conflict environment,it is still challenging to maintain the mission performance of flying Ad hoc networks(FANET),which limits the application of Unmanned Aerial Vehicle(UAV)swarms in harsh environments.This paper proposes an intelligent framework to quickly recover the cooperative coveragemission by aggregating the historical spatio-temporal network with the attention mechanism.The mission resilience metric is introduced in conjunction with connectivity and coverage status information to simplify the optimization model.A spatio-temporal node pooling method is proposed to ensure all node location features can be updated after destruction by capturing the temporal network structure.Combined with the corresponding Laplacian matrix as the hyperparameter,a recovery algorithm based on the multi-head attention graph network is designed to achieve rapid recovery.Simulation results showed that the proposed framework can facilitate rapid recovery of the connectivity and coverage more effectively compared to the existing studies.The results demonstrate that the average connectivity and coverage results is improved by 17.92%and 16.96%,respectively compared with the state-of-the-art model.Furthermore,by the ablation study,the contributions of each different improvement are compared.The proposed model can be used to support resilient network design for real-time mission execution. 展开更多
关键词 RESILIENCE cooperative mission FANET spatio-temporal node pooling multi-head attention graph network
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An Improved UNet Lightweight Network for Semantic Segmentation of Weed Images in Corn Fields
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作者 Yu Zuo Wenwen Li 《Computers, Materials & Continua》 SCIE EI 2024年第6期4413-4431,共19页
In cornfields,factors such as the similarity between corn seedlings and weeds and the blurring of plant edge details pose challenges to corn and weed segmentation.In addition,remote areas such as farmland are usually ... In cornfields,factors such as the similarity between corn seedlings and weeds and the blurring of plant edge details pose challenges to corn and weed segmentation.In addition,remote areas such as farmland are usually constrained by limited computational resources and limited collected data.Therefore,it becomes necessary to lighten the model to better adapt to complex cornfield scene,and make full use of the limited data information.In this paper,we propose an improved image segmentation algorithm based on unet.Firstly,the inverted residual structure is introduced into the contraction path to reduce the number of parameters in the training process and improve the feature extraction ability;secondly,the pyramid pooling module is introduced to enhance the network’s ability of acquiring contextual information as well as the ability of dealing with the small target loss problem;and lastly,Finally,to further enhance the segmentation capability of the model,the squeeze and excitation mechanism is introduced in the expansion path.We used images of corn seedlings collected in the field and publicly available corn weed datasets to evaluate the improved model.The improved model has a total parameter of 3.79 M and miou can achieve 87.9%.The fps on a single 3050 ti video card is about 58.9.The experimental results show that the network proposed in this paper can quickly segment corn weeds in a cornfield scenario with good segmentation accuracy. 展开更多
关键词 Semantic segmentation deep learning UNet pyramid pooling module
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Local Torrential Rainfall Event within a Mei-Yu Season Mesoscale Convective System:Importance of Back-Building Processes
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作者 Honglei ZHANG Ming XUE +2 位作者 Hangfeng SHEN Xiaofan LI Guoqing ZHAI 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第5期847-863,共17页
An extreme rainfall event occurred over Hangzhou,China,during the afternoon hours on 24 June 2013.This event occurred under suitable synoptic conditions and the maximum 4-h cumulative rainfall amount was over 150 mm.T... An extreme rainfall event occurred over Hangzhou,China,during the afternoon hours on 24 June 2013.This event occurred under suitable synoptic conditions and the maximum 4-h cumulative rainfall amount was over 150 mm.This rainfall event had two major rainbands.One was caused by a quasi-stationary convective line,and the other by a backbuilding convective line related to the interaction of the outflow boundary from the first rainband and an existing low-level mesoscale convergence line associated with a mei-yu frontal system.The rainfall event lasted 4 h,while the back-building process occurred in 2 h when the extreme rainfall center formed.So far,few studies have examined the back-building processes in the mei-yu season that are caused by the interaction of a mesoscale convergence line and a convective cold pool.The two rainbands are successfully reproduced by the Weather Research and Forecasting(WRF)model with fourlevel,two-way interactive nesting.In the model,new cells repeatedly occur at the west side of older cells,and the backbuilding process occurs in an environment with large CAPE,a low LFC,and plenty of water vapor.Outflows from older cells enhance the low-level convergence that forces new cells.High precipitation efficiency of the back-building training cells leads to accumulated precipitation of over 150 mm.Sensitivity experiments without evaporation of rainwater show that the convective cold pool plays an important role in the organization of the back-building process in the current extreme precipitation case. 展开更多
关键词 torrential rainfall back-building processes numerical simulation trigger mechanism convergence line convective cold pool
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Tackling the proton limit under industrial electrochemical CO_(2)reduction by a local proton shuttle
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作者 Tianye Shao Kang Yang +4 位作者 Sheng Chen Min Zheng Ying Zhang Qiang Li Jingjing Duan 《Carbon Energy》 SCIE EI CAS CSCD 2024年第4期233-243,共11页
Industrial CO_(2)electroreduction has received tremendous attentions for resolution of the current energy and environmental crisis,but its performance is greatly limited by mass transport at high current density.In th... Industrial CO_(2)electroreduction has received tremendous attentions for resolution of the current energy and environmental crisis,but its performance is greatly limited by mass transport at high current density.In this work,an ion‐polymer‐modified gas‐diffusion electrode is used to tackle this proton limit.It is found that gas diffusion electrode‐Nafion shows an impressive performance of 75.2%Faradaic efficiency in multicarbon products at an industrial current density of 1.16 A/cm^(2).Significantly,in‐depth electrochemical characterizations combined with in situ Raman have been used to determine the full workflow of protons,and it is found that HCO_(3)^(−)acts as a proton pool near the reaction environment,and HCO_(3)^(−)and H_(3)O^(+)are local proton donors that interact with the proton shuttle−SO_(3)^(−)from Nafion.With rich proton hopping sites that decrease the activation energy,a“Grotthuss”mechanism for proton transport in the above system has been identified rather than the“Vehicle”mechanism with a higher energy barrier.Therefore,this work could be very useful in terms of the achievement of industrial CO_(2)reduction fundamentally and practically. 展开更多
关键词 industrial CO_(2)electroreduction proton donor proton pool proton shuttle proton transport mechanism
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Towards implementation of alloy-specific thermo-fluid modelling for laser powder-bed fusion of Mg alloys
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作者 Mohammad Hoseini-Athar Mikael Ersson Peter Hedström 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第6期2327-2344,共18页
Multi-physics thermo-fluid modeling has been extensively used as an approach to understand melt pool dynamics and defect formation as well as optimizing the process-related parameters of laser powder-bed fusion(L-PBF)... Multi-physics thermo-fluid modeling has been extensively used as an approach to understand melt pool dynamics and defect formation as well as optimizing the process-related parameters of laser powder-bed fusion(L-PBF).However,its capabilities for being implemented as a reliable tool for material design,where minor changes in material-related parameters must be accurately captured,is still in question.In the present research,first,a thermo-fluid computational fluid dynamics(CFD)model is developed and validated against experimental data.Considering the predicted material properties of the pure Mg and commercial ZK60 and WE43 Mg alloys,parametric studies are done attempting to elucidate how the difference in some of the material properties,i.e.,saturated vapor pressure,viscosity,and solidification range,can influence the melt pool dynamics.It is found that a higher saturated vapor pressure,associated with the ZK60 alloy,leads to a deeper unstable keyhole,increasing the keyhole-induced porosity and evaporation mass loss.Higher viscosity and wider solidification range can increase the non-uniformity of temperature and velocity distribution on the keyhole walls,resulting in increased keyhole instability and formation of defects.Finally,the WE43 alloy showed the best behavior in terms of defect formation and evaporation mass loss,providing theoretical support to the extensive use of this alloy in L-PBF.In summary,this study suggests an approach to investigate the effect of materials-related parameters on L-PBF melting and solidification,which can be extremely helpful for future design of new alloys suitable for L-PBF. 展开更多
关键词 Mg alloys Laser powder-bed fusion(L-PBF) Melt pool dynamics Computational fluid dynamics Fluid flow
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Evolution Mechanism of a Severe Squall Line Triggered by the Coupling of a Sea Breeze Front and a Gust Front
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作者 万夫敬 孙敏 +2 位作者 庞华基 赵海军 赵传湖 《Journal of Tropical Meteorology》 SCIE 2024年第2期200-210,共11页
In the present study, a severe squall line(SL) was analyzed by using intensive observational surface data and radar monitoring products. In this process, mesoscale convergence lines, such as the sea breeze front(SBF),... In the present study, a severe squall line(SL) was analyzed by using intensive observational surface data and radar monitoring products. In this process, mesoscale convergence lines, such as the sea breeze front(SBF), gust front and dry line, served as the main triggering and strengthening factors. The transition from convection triggering to the formation of the initial shape was mainly affected by the convergence line of the SBF, which combined with thermal convection to form the main parts of the SL. In the later stage, the convergence line of the gust front merged with other convergence lines to form a series of strong convective cells. The SBF had good indicative significance in terms of severe convective weather warnings. The suitable conditions of heat, water vapor and vertical wind shear on the Shandong Peninsula were beneficial to the maintenance of the SL. Before SL occurrence, tropopause folding strengthened, which consequently enhanced the baroclinic property in the middle and upper troposphere. The high sensible heat flux at the surface easily produced a positive potential vorticity anomaly in the low layer, resulting in convective instability, which was conducive to the maintenance of these processes. In the system, when precipitation particles passed through the unsaturated air layer, they underwent strong evaporation, melting or sublimation, and the cooling effect formed negative buoyancy, which accelerated the sinking of the air and promoted the sustained development of the surface gale. Together with the development of lowlevel mesocyclones, the air pressure decreased rapidly, which was conducive to gale initiation. 展开更多
关键词 squall line sea breeze front gust front cold pool thunderstorm gale
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Mesoscale and Microphysical Characteristics of a Double Rain Belt Event in South China on May 10–13,2022
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作者 郭照华 谌芸 +1 位作者 肖天贵 曾智琳 《Journal of Tropical Meteorology》 SCIE 2024年第1期61-75,共15页
A second rain belt sometimes occurs ahead of a frontal rain belt in the warm sector over coastal South China,leading to heavy precipitation.We examined the differences in the mesoscale characteristics and microphysics... A second rain belt sometimes occurs ahead of a frontal rain belt in the warm sector over coastal South China,leading to heavy precipitation.We examined the differences in the mesoscale characteristics and microphysics of the frontal and warm sector rain belts that occurred in South China on May 10–13,2022.The southern rain belt occurred in an environment with favorable mesoscale conditions but weak large-scale forcing.In contrast,the northern rain belt was related to low-level horizontal shear and the surface-level front.The interaction between the enhanced southeasterly winds and the rainfall-induced cold pool promoted the persistent growth of convection along the southern rain belt.The convective cell propagated east over the coastal area,where there was a large temperature gradient.The bow-shaped echo in this region may be closely related to the rear-inflow jet.By contrast,the initial convection of the northern rain belt was triggered along the front and the region of low-level horizontal shear,with mesoscale interactions between the enhanced warm-moist southeasterly airflow and the cold dome associated with the earlier rain.The terrain blocked the movement of the cold pool,resulting in the stagnation of the frontal convective cell at an early stage.Subsequently,a meso-γ-scale vortex formed during the rapid movement of the convective cell,corresponding to an enhancement of precipitation.The representative raindrop spectra for the southern rain belt were characterized by a greater number and higher density of raindrops than the northern rain belt,even though both resulted in comparable hourly rainfalls.These results help us better understand the characteristics of double rain belts over South China. 展开更多
关键词 double rain belts in South China mesoscale rainstorm cyclonic shear line cold pool bow-shaped echo microphysical characteristics
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奇异线性空间上的Pooling设计及其紧界(英文)
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作者 刘雪梅 接贤 高有 《黑龙江大学自然科学学报》 CAS 北大核心 2014年第5期583-588,共6页
基于有限域上的奇异线性空间的两种不同形式的子空间,构造一族具有纠错能力的Pooling设计,讨论其析取性质,给出Pooling设计的紧界。
关键词 pooling设计 d^e-析取矩阵 奇异线性空间 紧界
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The Importance of Setting Treatment Goals for Cardiovascular Diseases
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作者 David S. Schade Bramara Nagamallika Godasi +1 位作者 Teodor Duro Robert Philip Eaton 《World Journal of Cardiovascular Diseases》 CAS 2024年第1期10-15,共6页
Background: Guidelines are issued by most major organizations that focus on a specific disease entity. Guidelines should be a significant help to the practicing physician who may not be up-to-date with the recent medi... Background: Guidelines are issued by most major organizations that focus on a specific disease entity. Guidelines should be a significant help to the practicing physician who may not be up-to-date with the recent medical literature. Unfortunately, when conflicting guidelines for a specific disease are published, confusion results. Purpose: This article provides a suggested guideline outcome measure that would benefit the physician and patient. Methods: A review of 19 different guidelines for cardiovascular disease treatment is one example of the lack of specific outcomes that currently exist. The basic problem with most guidelines is that they do not state the expected end result (i.e., the benefit to the patient) if that guideline is followed. When guidelines use cardiovascular disease risk factors to dictate therapy, the end benefit is never stated so that the patient can make an appropriate choice of which (if any) guideline to follow. Results: A good example is guidelines published by the American Heart Association for reducing cardiovascular disease. These guidelines are risk factor based and only indicate that cardiovascular disease would be reduced if followed. No specific percentage in the reduction of the incidence of disease is given. In contrast, when elimination of the disease is the stated goal of the guideline, the end result is clear. To date, this goal has been stated by only one organization devoted to eliminating cardiovascular disease. Conclusion: Guidelines need to be written to provide the physician and the patient with a specific end point that is expected when the guideline is followed. Patient acceptance and compliance will be much improved if the patient knows the risk/benefit of following the guideline’s recommendations. 展开更多
关键词 Guideline Goals for Cardiovascular Disease Prevention Cardiovascular Disease Risk Factors for Cardiovascular Disease Pooled Cohort Equations
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采用Pyrosequencing和Pooling技术对SNP位点多态性分析
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作者 赵珍敏 张素华 《中国司法鉴定》 2014年第1期56-58,共3页
目的建立基于pyrosequencing和Pooling技术进行SNP位点的法医学多态性分析技术。方法对50名无关个体样本建立一适合pyrosequencing检测的组池;采用PyroMark Assay Design 2.0软件进行SNP位点等位基因定量分析的引物设计;对组池样本PCR... 目的建立基于pyrosequencing和Pooling技术进行SNP位点的法医学多态性分析技术。方法对50名无关个体样本建立一适合pyrosequencing检测的组池;采用PyroMark Assay Design 2.0软件进行SNP位点等位基因定量分析的引物设计;对组池样本PCR产物进行焦磷酸测序检测。结果检测的3个SNP位点多态性良好,其中位点rs220028与以往人群调查后频率数据无显著差异。结论采用pyrosequencing和Pooling技术对SNP位点进行多态性分析,适合于位点的初筛及大规模群体调查。该技术准确可靠,方便快捷。 展开更多
关键词 PYROSEQUENCING pooling SNP
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