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基于GIS的强震区泥石流流域崩滑物源演化强度评价

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地理与地理信息科学 2020年第1期36卷 58-64页

作者：熊江唐川龚凌枫史青云李宁成都理工大学地质灾害防治与地质环境保护国家重点实验室

为探究震后泥石流流域内崩滑物源演化强度,基于高清遥感影像和GIS平台,计算物源面积、长轴及其演化速度,将演化速度(分为3级并赋值)作为物源演化强度评价指标,并构建物源演化强度评价模型。物源演化强度评价结论如下:1)物源数量和总面... 详细信息

为探究震后泥石流流域内崩滑物源演化强度,基于高清遥感影像和GIS平台,计算物源面积、长轴及其演化速度,将演化速度(分为3级并赋值)作为物源演化强度评价指标,并构建物源演化强度评价模型。物源演化强度评价结论如下:1)物源数量和总面积随物源面积、长轴演化速度等级提高而逐渐减少;2)物源演化弱强度、中等强度、高强度物源数量分别为1166处、255处、121处,分别占总数的75161%、16154%、7185%;3)高演化强度物源主要为大型崩滑物源,多呈长条状分布在沟道两侧坡度较大地方,弱演化强度物源为小型崩滑物源,多分布在远离沟道两岸坡度较缓地区;4)细粒物质运移、植被恢复、物源量差异是导致演化强度差异的重要原因。

关键词： GIS 崩滑物源演化强度评价

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以车库为例浅析重力式挡土墙安全性

价值工程 2017年第7期36卷 96-97页

作者：宋坤史青云昆明理工大学国土资源工程学院昆明650091 云南大学资源环境与地球科学学院昆明650091

基坑围护是指为保护基坑周围环境及建筑的安全和地下结构施工,对基坑侧壁及周边环境采取的加固、支挡的措施。基坑围护方法多种多样,其中重力式围护墙具有施工方便、效率高、工期短、成本低等优点,是应用较为广泛的一种基坑围护形式。... 详细信息

基坑围护是指为保护基坑周围环境及建筑的安全和地下结构施工,对基坑侧壁及周边环境采取的加固、支挡的措施。基坑围护方法多种多样,其中重力式围护墙具有施工方便、效率高、工期短、成本低等优点,是应用较为广泛的一种基坑围护形式。本文以某车库为例应用重力式围护墙方法进行基坑工程的围护研究,验证此方法的安全性、稳定性和实效性。

关键词：基坑围护重力式围护墙加固

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绝经后子宫内膜增厚的临床与病理分析

中国妇幼保健 2007年第2期22卷 209-211页

作者：郑凤英时青云吴姗姗北京市通州区新华医院妇产科首都医科大学附属北京友谊医院 101100

目的:探讨绝经后子宫内膜增厚的影响因素,并进行病理类型分析。方法:分析190例绝经后经B超检查子宫内膜厚度大于4 mm,并行诊断性刮宫及(或)子宫切除妇女的临床和病理资料。结果:①190例患者中,应用激素替代治疗(hormone rep lacem ent t... 详细信息

目的:探讨绝经后子宫内膜增厚的影响因素,并进行病理类型分析。方法:分析190例绝经后经B超检查子宫内膜厚度大于4 mm,并行诊断性刮宫及(或)子宫切除妇女的临床和病理资料。结果:①190例患者中,应用激素替代治疗(hormone rep lacem ent therapy,HRT)者68例占35.8%,高血压者37例占19.5%,应用他莫西酚者15例占7.9%。此3项是影响子宫内膜增厚的主要因素,其他因素有吸烟、不育、糖尿病;②子宫内膜厚度4 mm者48例,以萎缩性子宫内膜表现为主,未见有子宫内膜癌的发生;子宫内膜厚度57 mm者62例,以内膜增生、内膜增殖症为主,不典型增生2例,内膜癌6例;子宫内膜厚度89 mm者42例,其中内膜癌11例,非典型增生4例;子宫内膜厚度≥10 mm者38例,其中内膜癌15例,不典型增生6例,内膜癌的发病率明显增高。结论:子宫内膜癌与子宫内膜的增厚有密切相关性。绝经后子宫内膜厚度>4 mm者应行诊断性刮宫。

关键词：绝经子宫内膜增厚子宫内膜癌

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顶升装置新型夹持机构优化分析

机械设计 2017年第9期34卷 1-5页

作者：赵瑞营章青石云飞芮建天津大学机械工程学院天津300072

顶升装置是保证深海采油平台浮托安装顺利进行的关键装置。针对顶升装置夹持结构中的薄弱环节,提出了一种新型的插板式夹持机构。以支撑筒的内径、高度和插板槽距底面高度为设计变量,支撑筒的总质量最小为目标函数,最大等效应力和最大... 详细信息

顶升装置是保证深海采油平台浮托安装顺利进行的关键装置。针对顶升装置夹持结构中的薄弱环节,提出了一种新型的插板式夹持机构。以支撑筒的内径、高度和插板槽距底面高度为设计变量,支撑筒的总质量最小为目标函数,最大等效应力和最大变形量为约束条件,通过有限元分析软件对新型夹持机构的直接承重部件支撑筒结构进行优化分析,明显减轻了新型夹持机构支撑筒的质量,结构更加简单合理,可靠性高。

关键词：顶升装置夹持结构有限元优化分析

Joint Feature Encoding and Task Alignment Mechanism for Emotion-Cause Pair Extraction

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Computers, Materials & Continua 2025年第1期82卷 1069-1086页

作者： shi Li Didi Sun College of Computer and Control Engineering Northeast Forestry UniversityHarbin150040China

With the rapid expansion of social media,analyzing emotions and their causes in texts has gained significant ***-cause pair extraction enables the identification of causal relationships between emotions and their triggers within a text,facilitating a deeper understanding of expressed sentiments and their underlying *** comprehension is crucial for making informed strategic decisions in various business and societal ***,recent research approaches employing multi-task learning frameworks for modeling often face challenges such as the inability to simultaneouslymodel extracted features and their interactions,or inconsistencies in label prediction between emotion-cause pair extraction and independent assistant tasks like emotion and cause *** address these issues,this study proposes an emotion-cause pair extraction methodology that incorporates joint feature encoding and task alignment *** model consists of two primary components:First,joint feature encoding simultaneously generates features for emotion-cause pairs and clauses,enhancing feature interactions between emotion clauses,cause clauses,and emotion-cause ***,the task alignment technique is applied to reduce the labeling distance between emotion-cause pair extraction and the two assistant tasks,capturing deep semantic information interactions among *** proposed method is evaluated on a Chinese benchmark corpus using 10-fold cross-validation,assessing key performance metrics such as precision,recall,and F1 *** results demonstrate that the model achieves an F1 score of 76.05%,surpassing the state-of-the-art by 1.03%.The proposed model exhibits significant improvements in emotion-cause pair extraction(ECPE)and cause extraction(CE)compared to existing methods,validating its *** research introduces a novel approach based on joint feature encoding and task alignment mechanisms,contributing to advancements in emotion-c

关键词： Emotion-cause pair extraction interactive information enhancement joint feature encoding label consistency task alignment mechanisms

A Novel Control Strategy Based onπ-VSG for Inter-Face Converter in Hybrid Microgrid

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Energy Engineering 2025年第2期122卷 471-492页

作者： Kai shi Dongyang Yang Department of Electrical Engineering Jiangsu UniversityZhenjiang21200China

The rapid development of new energy power generation technology and the transformation of power electronics in the core equipment of source-grid-load drives the power system towards the“double-high”development pattern of“high proportion of renewable energy”and“high proportion of power electronic equipment”.To enhance the transient performance of AC/DC hybrid microgrid(HMG)in the context of“double-high,”aπtype virtual synchronous generator(π-VSG)control strategy is applied to bidirectional interface converter(BIC)to address the issues of lacking inertia and poor disturbance immunity caused by the high penetration rate of power electronic equipment and new ***,the virtual synchronous generator mechanical motion equations and virtual capacitance equations are used to introduce the virtual inertia control equations that consider the transient performance of HMG;based on the equations,theπ-type equivalent control model of the BIC is ***,the inertia power is actively transferred through the BIC according to the load fluctuation to compensate for the system’s inertia ***,theπ-VSG control utilizes small-signal analysis to investigate howthe fundamental parameters affect the overall stability of the HMG and incorporates power step response curves to reveal the relationship between the control’s virtual parameters and transient ***,the PSCAD/EMTDC simulation results show that theπ-VSG control effectively improves the immunity of AC frequency and DC voltage in the HMG system under the load fluctuation condition,increases the stability of the HMG system and satisfies the power-sharing control objective between the AC and DC subgrids.

关键词： Hybrid AC/DC microgrid electromotive force of DC motor interface converter virtual synchronous generator control

Detection and Recognition of Spray Code Numbers on Can Surfaces Based on OCR

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Computers, Materials & Continua 2025年第1期82卷 1109-1128页

作者： Hailong Wang Junchao shi School of Computer Science Zhongyuan University of TechnologyZhengzhou450007China

A two-stage algorithm based on deep learning for the detection and recognition of can bottom spray codes and numbers is proposed to address the problems of small character areas and fast production line speeds in can bottom spray code number *** the coding number detection stage,Differentiable Binarization Network is used as the backbone network,combined with the Attention and Dilation Convolutions Path Aggregation Network feature fusion structure to enhance the model detection *** terms of text recognition,using the Scene Visual Text Recognition coding number recognition network for end-to-end training can alleviate the problem of coding recognition errors caused by image color distortion due to variations in lighting and background *** addition,model pruning and quantization are used to reduce the number ofmodel parameters to meet deployment requirements in resource-constrained environments.A comparative experiment was conducted using the dataset of tank bottom spray code numbers collected on-site,and a transfer experiment was conducted using the dataset of packaging box production *** experimental results show that the algorithm proposed in this study can effectively locate the coding of cans at different positions on the roller conveyor,and can accurately identify the coding numbers at high production line *** Hmean value of the coding number detection is 97.32%,and the accuracy of the coding number recognition is 98.21%.This verifies that the algorithm proposed in this paper has high accuracy in coding number detection and recognition.

关键词： Can coding recognition differentiable binarization network scene visual text recognition model pruning and quantification transport model

The shadow and gamma-ray bursts of a Schwarzschild black hole in asymptotic safety

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Communications in Theoretical Physics 2025年第2期77卷 121-131页

作者： Yuxuan shi Hongbo Cheng Department of Physics East China University of Science and Technology The Shanghai Key Laboratory of Astrophysics

The effects and rules of the dimensionless parameter ξ on neutrino annihilation v+■→e-+e+dominated gamma-ray bursts are analysed and investigated within the context of black holes in asymptotic *** also computationally model photon orbits around black holes,as photons and neutrinos have the same geodesic equations near black *** show that the black hole shadow radius decreases with increasing ξ.Calculations are made to determine the temperature of the accretion disk surrounding the black hole and the ratio ■Newtof energy deposition per unit time and compared to that of the Newtonian *** accretion disk temperature peaks at a higher temperature due to quantum gravity corrections,which increases the probability of neutrino emission from the black *** is interesting to note that larger quantum gravity effects cause the ratio value to significantly *** the neutrinoantineutrino annihilation process,the energy deposition rate is sufficient even while the energy conversion is inhibited because of quantum ***-ray bursts might originate from the corrected annihilation ***,we examine the derivative d■/dr about the star radius *** findings demonstrate that the ratio is lowered by the black hole's quantum *** neutrino pair annihilation grows weaker the more prominent the influence of quantum gravity.

关键词： quantum gravity black hole gamma-ray burst

基于双向生成对抗网络的感知哈希图像内容取证算法

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计算机学报 2023年第12期46卷 2551-2572页

作者：马宾王一利徐健王春鹏李健周琳娜施云庆齐鲁工业大学(山东省科学院)计算机科学与技术学部济南250300 山东省计算机网络重点实验室济南250001 山东财经大学计算机科学与技术学院济南250014 北京邮电大学网络空间安全学院北京100876 新泽西理工大学电气与计算机系美国纽瓦克07102

传统的感知哈希算法通过提取图像特定属性生成感知哈希序列,难以充分利用原始图像全部特征信息,影响了基于感知哈希的图像内容认证与版权保护能力.本文提出一种基于双向生成对抗网络(Bidirectional Generative Adversarial Network,BiG... 详细信息

传统的感知哈希算法通过提取图像特定属性生成感知哈希序列,难以充分利用原始图像全部特征信息,影响了基于感知哈希的图像内容认证与版权保护能力.本文提出一种基于双向生成对抗网络(Bidirectional Generative Adversarial Network,BiGAN)的无监督感知哈希图像内容取证算法,基于编码网络、生成网络和判别网络间的双向迭代对抗,生成具有较强图像语义特征表示能力的感知哈希码;并通过在编码网络和生成网络间添加跳接层网络结构,将原始图像不同维度的特征信息传递到生成网络,提高生成网络语义特征学习能力与网络收敛速度;同时,在对抗损失中添加MSE误差损失,增强生成图像的视觉质量与细节表示能力;最后,基于网络间的多重迭代与对抗训练,输出兼具相同内容图像认证鲁棒性和不同内容图像区分敏感性的高性能图像感知哈希码.本研究首次采用大型图像数据库进行算法性能评价,实验结果表明基于双向生成对抗网络的感知哈希图像内容取证算法与当前其他优秀研究方案相比具有更强的图像内容取证性能.

关键词：图像取证生成对抗网络感知哈希跳接均方误差