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ON THE CAUCHY PROBLEM FOR THE GENERALIZED BOUSSINESQ EQUATION WITH A DAMPED TERM

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Acta Mathematica Scientia 2024年第5期44卷 1766-1786页

作者： xiao SU Shubin wang College of Science Henan University of TechnologyZhengzhou450001China School of Mathematics and Statistics Zhengzhou UniversityZhengzhou450001China

This paper is devoted to the Cauchy problem for the generalized damped Boussinesq equation with a nonlinear source term in the natural energy *** the help of linear time-space estimates,we establish the local existence and uniqueness of solutions by means of the contraction mapping *** global existence and blow-up of the solutions at both subcritical and critical initial energy levels are ***,we construct the sufficient conditions of finite time blow-up of the solutions with arbitrary positive initial energy.

关键词： damped Boussinesq equation Cauchy problem global solutions blow-up

An online value iteration method for linear-quadratic mean field social control with unknown dynamics

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Science China(Information Sciences) 2024年第4期67卷 38-39页

作者： Bing-chang wang Shumei LI Ying CAO School of Control Science and Engineering Shandong University

Mean field(MF) models have been widely applied to economics, control theory, and other fields. Its prominent feature is that the individual influence on the overall population is negligible and the impact of the entire system to the single agent is significant and cannot be ignored. As a classical problem in control theory, linear quadratic(LQ) control for MF models has been widely investigated(e.g., [1, 2]).

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知识共享与价值创造:OCoP视角下众筹出版本质与功能再审视

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编辑之友 2022年第9期 23-29页

作者：胡晓王长潇北京师范大学人文和社会科学高等研究院广东珠海519087 北京师范大学新闻传播学院北京100875 北京师范大学未来教育学院广东珠海519087

众筹出版即读者预付费支持图书生产的按需出版模式,其实质是通过多社群意义协商实现知识共享和价值创造,主要满足当下小众网络社群的特定文化需求。众筹出版各方通过互联网平台即时交流、知识分享、参与协商,构建了一个拥有诸多出版情... 详细信息

众筹出版即读者预付费支持图书生产的按需出版模式,其实质是通过多社群意义协商实现知识共享和价值创造,主要满足当下小众网络社群的特定文化需求。众筹出版各方通过互联网平台即时交流、知识分享、参与协商,构建了一个拥有诸多出版情境的在线实践共同体(O nline Community of Practice,简称OCoP)。文章运用"实践共同体"(Community of Practice,简称CoP)框架对摩点众筹出版成功案例进行阐释,分析众筹参与者在图书出版过程中如何相互卷入、如何参与合作事业,以及如何实现智库共享。通过对众筹出版本质与功能的再审视,文章认为众筹出版是“出版+互联网”的融合发展形式之一,值得有条件推广。

关键词：众筹出版实践共同体知识共享价值创造网络平台

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国内典型城市降雨径流初期累积特征分析

中国环境科学 2015年第6期35卷 1719-1725页

作者：王倩张琼华王晓昌西安建筑科技大学环境与市政工程学院陕西西安710055

提出以携带50%污染物负荷的径流定义初期雨水,选取累积50%污染物负荷的历时(T50)及对应累积径流深度(D50)两个参数,总结分析典型山地城市、平原城市、河网城市等6个城市17场降雨径流污染物累积特征.进一步以山地城市和平原城市为例,探... 详细信息

提出以携带50%污染物负荷的径流定义初期雨水,选取累积50%污染物负荷的历时(T50)及对应累积径流深度(D50)两个参数,总结分析典型山地城市、平原城市、河网城市等6个城市17场降雨径流污染物累积特征.进一步以山地城市和平原城市为例,探讨了不同降雨强度、区域环境径流污染物累积特征及相互影响.结果表明,径流污染物累积趋势完全一致但特征不同,山地城市、河网城市、高原城市和河口城市表现为初期累积,平原城市则表现为中期累积.随着雨强增大,污染物D50骤增,T50锐减.相比平原城市,山地城市不同类型污染物D50更大、T50更小,山地城市和平原城市分别截留初期7.4mm和5.2mm径流可以控制50%污染物负荷.

关键词：降雨径流初期雨水 D50和T50 降雨强度

Cascade failure modeling and resilience analysis of mine cyber physical systems under deliberate attacks

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JOURNAL OF SAFETY SCIENCE AND RESILIENCE 2024年第3期5卷 266-280页

作者： wang, Xinping Zhu, Jialin Su, chang Zhen, Xinyue Xian Univ Sci & Technol Sch Management Xian 710054 Peoples R China Xian Univ Sci & Technol Sch Safety Sci & Engn Xian 710054 Peoples R China

Guided by the intelligent construction of coal mines and integrating the concept of the Cyber-Physical System (CPS), a novel approach to a coal mine information-physical fusion system is proposed. This concept emerges from the advancement of intelligent mines and the growing need for enhanced safety in coal mine operations. From a system safety perspective, this approach aims to effectively evaluate security issues by better integrating the informational and physical layers of intelligent mines. Currently, research in areas such as power grids and water networks has widely adopted concepts of cascade failures and robustness. It is suggested that the CPS framework be adapted to the mining sector. Considering the critical role of coal mines in China's energy security and their vulnerability to cyber attacks, a mine-specific CPS system is designed. This system incorporates a model of mine information-physical fusion, including networks for mine operations, management, and control, tailored to the unique conditions of mine shafts and underground settings. Utilizing Markov process theory, the paper delves into the theoretical study of the cascade failure process under deliberate attack strategies. This analysis is essential to effectively assess the safety issues within the information-physical system, providing vital support for fault prediction and safety analysis. The model of cascading failures in the mine information-physical system is developed, and based on an analysis of resilience and robustness, the study identifies key factors influencing the security of mine information-physical systems. Critical factors affecting the reliability of these systems include the number of system nodes, node coupling, edge count, and the interconnection methods of the dual-layer dependency network. The paper concludes by discussing the challenges in analyzing the security of information-physical systems and suggesting directions for future research.

关键词： Mine cyber physical system Cascading failure Resilience Robustness INTERDEPENDENT NETWORK RELIABILITY ASSESSMENT COMPLEX NETWORKS ROBUSTNESS SECURE

Multilevel Attention Unet Segmentation Algorithmfor Lung Cancer Based on CT Images

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Computers, Materials & Continua 2024年第2期78卷 1569-1589页

作者： Huan wang Shi Qiu Benyue Zhang Lixuan xiao Xi’an Institute of Optics and Precision Mechanics Chinese Academy of SciencesXi’anChina School of Biomedical Engineering Fourth Military Medical UniversityXi’anChina University of Illinois at Urbana Champion ChampaignUSA

Lung cancer is a malady of the lungs that gravely jeopardizes human ***,early detection and treatment are paramount for the preservation of human *** computed tomography(CT)image sequences can explicitly delineate the pathological condition of the *** meet the imperative for accurate diagnosis by physicians,expeditious segmentation of the region harboring lung cancer is of utmost *** utilize computer-aided methods to emulate the diagnostic process in which physicians concentrate on lung cancer in a sequential manner,erect an interpretable model,and attain segmentation of lung *** specific advancements can be encapsulated as follows:1)Concentration on the lung parenchyma region:Based on 16-bit CT image capturing and the luminance characteristics of lung cancer,we proffer an intercept histogram algorithm.2)Focus on the specific locus of lung malignancy:Utilizing the spatial interrelation of lung cancer,we propose a memory-based Unet architecture and incorporate skip connections.3)Data Imbalance:In accordance with the prevalent situation of an overabundance of negative samples and a paucity of positive samples,we scrutinize the existing loss function and suggest a mixed loss *** results with pre-existing publicly available datasets and assembled datasets demonstrate that the segmentation efficacy,measured as Area Overlap Measure(AOM)is superior to 0.81,which markedly ameliorates in comparison with conventional algorithms,thereby facilitating physicians in diagnosis.

关键词： Lung cancer computed tomography computer-aided diagnosis Unet segmentation

Neurotoxicity of tetramethylammonium ion on larval and juvenile zebrafish:Effects on neurobehaviors and multiple biomarkers

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Journal of Environmental Sciences 2024年第9期143卷 138-147页

作者： Ruixin Zhang Rui wang Jiajun chang GDaniel Sheng Daqiang Yin Key Laboratory of Yangtze River Water Environment Ministry of EducationCollege of Environmental Science and EngineeringTongji UniversityShanghai 200092China Shanghai Institute of Pollution Control and Ecological Security Shanghai 200092China

Tetramethylammonium hydroxide(TMAH)is an important compound that utilized and released by the rapidly expanding semiconductor industry,which could hardly be removed by the conventional wastewater treatment *** a cholinergic agonist,the tetramethylammonium ion(TMA^(+))has been reported to induce toxicity to muscular and respiratory systems of mammals and human,however the toxicity on aquatic biota remains poorly *** investigated the neurotoxic effects of TMA^(+)exposure on zebrafish,based on neurobehavior tests and a series of *** inhibitions on the swimming distance of zebrafish larvae were observed when the exposure level exceeded 50 mg/L,and significant alterations on swimming path angles(straight and deflective movements)occurred even at 10 mg/*** tested neurobehavioral endpoints of zebrafish larvae were significantly positively correlated with reactive oxygen species(ROS)and malondialdehyde(MDA),significantly negatively related with the activities of antioxidant enzymes,but not significantly correlated with the level of acetylcholinesterase(AChE).Such relationship indicates that the observed neurotoxic effects on swimming behavior of zebrafish larvae is mainly driven by oxidative stress,rather than the alterations of *** the highest exposure concentration(200 mg/L),TMA^(+)evoked more severe toxicity on zebrafish juveniles,showing significantly stronger elevation on the MDA activity,and greater inhibitions on the activities of antioxidant enzymes and ACh E,suggesting juveniles were more susceptible to TMA^(+)exposure than larval zebrafish.

关键词： Tetramethylammonium Zebrafish Oxidative stress Acetylcholinesterase Neurobehavior

Potential evaluation of saline aquifers for the geological storage of carbon dioxide: A case study of saline aquifers in the Qian-5 member in northeastern Ordos Basin

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China Geology 2024年第1期7卷 12-25页

作者： Yan Li Peng Li Hong-jun Qu Gui-wen wang xiao-han Sun chang Ma Tian-xing Yao Guoneng Jinjie Energy Co. Ltd.Shenmu 719319China Department of Geology Northwest UniversityXi’an 710069China Carbon Neutrality College(Yulin) Northwest UniversityXi’an 710069China National&Local Joint Engineering Research Center of Carbon Capture and Storage Technology Xi’an 710069China

The well-developed coal electricity generation and coal chemical industries have led to huge carbon dioxide(CO_(2))emissions in the northeastern Ordos *** geological storage of CO_(2) in saline aquifers is an effective backup way to achieve carbon *** this case,the potential of saline aquifers for CO_(2) storage serves as a critical basis for subsequent geological storage *** study calculated the technical control capacities of CO_(2) of the saline aquifers in the fifth member of the Shiqianfeng Formation(the Qian-5 member)based on the statistical analysis of the logging and the drilling and core data from more than 200 wells in the northeastern Ordos Basin,as well as the sedimentary facies,formation lithology,and saline aquifer development patterns of the Qian-5 *** results show that(1)the reservoirs of saline aquifers in the Qian-5 member,which comprise distributary channel sand bodies of deltaic plains,feature low porosities and permeabilities;(2)The study area hosts three NNE-directed saline aquifer zones,where saline aquifers generally have a single-layer thickness of 3‒8 m and a cumulative thickness of 8‒24 m;(3)The saline aquifers of the Qian-5 member have a total technical control capacity of CO_(2) of 119.25×10^(6) *** the largest scale and the highest technical control capacity(accounting for 61%of the total technical control capacity),the Jinjie-Yulin saline aquifer zone is an important prospect area for the geological storage of CO_(2) in the saline aquifers of the Qian-5 member in the study area.

关键词： Carbon burial Carbon neutral CO_(2) storage in saline aquifer Distributary channel sand body Potential evaluation Technical control capacity CO_(2)geological storage engineering Ordos Basin

An electromagnetic semi-active dynamic vibration absorber for thin-walled workpiece vibration suppression in mirror milling

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Applied Mathematics and Mechanics(English Edition) 2024年第8期45卷 1315-1334页

作者： Jianghua KONG Bei DING Wei wang Zhixia wang Juliang xiao Hongyun QIU School of Mechanical Engineering Tianjin UniversityTianjin 300350China Tianjin Key Laboratory of Nonlinear Dynamics and Control Tianjin 300350China Key Laboratory of Modern Mechanisms and Equipment Design of the State Ministry of Education Tianjin UniversityTianjin 300350China

As critical components of aircraft skins and rocket fuel storage tank shells,large thin-walled workpieces are susceptible to vibration and deformation during machining due to their weak local *** address these challenges,we propose a novel tunable electromagnetic semi-active dynamic vibration absorber(ESADVA),which integrates with a magnetic suction follower to form a followed ESADVA(follow-ESADVA)for mirror *** system combines a tunable magnet oscillator with a follower,enabling real-time vibration absorption and condition feedback throughout the milling ***,the device supports self-sensing and frequency adjustment by providing feedback to a linear actuator,which alters the distance between *** resolves the traditional issue of being unable to directly monitor vibration at the machining point due to space constraints and tool *** frequency shift characteristics and vibration absorption performance are comprehensively *** and experimental results demonstrate that the prototyped follow-ESADVA achieves frequency synchronization with the milling tool,resulting in a vibration suppression rate of approximately 47.57%.Moreover,the roughness of the machined surface decreases by18.95%,significantly enhancing the surface *** results of this work pave the way for higher-quality machined surfaces and a more stable mirror milling process.

关键词： semi-active dynamic vibration absorber(SADVA) mirror milling selfsensing vibration absorption tuning thin-walled workpiece