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Hydrodynamic Characteristics of Undular Tidal Bores in the Qiantang River Based on Field Observations

China Ocean Engineering 2024年第3期38卷 505-518页

作者： ZHANG Shu-yu PAN Cun-hong ZHANG Shen-yang li ruo-hua CHENG Wenlong XIE Dong-feng Zhejiang Tongji Vocational College of Science and Technology Hangzhou 311231China Zhejiang Institute of Hydraulics and Estuary Hangzhou 310020China

Understanding the undular tidal bores in the Qiantang River is essential for effective river management and *** breaking tidal bores have been studied extensively, reports on undular tidal bores in the Qiantang Riverremain limited. Furthermore, observed data on undular tidal bores fulfilling the requirements of short measurementtime intervals, and spring, medium, and neap tide coverage, and providing detailed data for the global vertical stratificationof flow velocity are quite limited. Based on field observations at Qige in the Qiantang estuary, we analyzedthe characteristics of undular tidal bores. The results showed that the flooding amplitude (a) of the first wave isalways larger than its ebbing amplitude (b). Moreover, the vertical distribution of the maximum flood velocity exhibitesthree shapes, influenced by the tidal range, while that of the maximum ebb velocity exhibites a single shape. Duringthe initial phase of the flood tide in the spring and medium tides, the upper water body experiences multiple oscillatingchanges along the flow direction, corresponding to the alternating process of the crest and trough of the tide levelupon the arrival of the tidal bore. The tidal range is a crucial parameter in tidal bore hydrodynamics. By establishingthe relationship between hydrodynamic parameters and tidal range, other hydrodynamic parameters, such as the tidalbore height, maximum flood depth–averaged velocity, maximum flood stratified velocity at the measurement points,and duration of the flood tide current, can be effectively predicted, thereby providing an important reference for rivermanagement and maintenance.

关键词： tidal bores Qiantang Estuary tidal bore height tidal bore velocity propagation speed

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钱塘江河口水质时段离散程度及对污染物通量估算的影响

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水电能源科学 2024年第1期42卷 36-39页

作者：李若华黄士稳浙江同济科技职业学院浙江杭州311231 浙江省水文管理中心浙江杭州310009

为估算钱塘江河口的污染物通量,基于钱塘江河口之江站2016年COD_(Mn)、TN、TP等3个水质指标的逐日水质数据及逐日净下泄流量,分析3个水质指标的时段离散程度、与净下泄流量的相关性及污染物月通量估算时忽略时均离散通量引起的误差大小... 详细信息

为估算钱塘江河口的污染物通量,基于钱塘江河口之江站2016年COD_(Mn)、TN、TP等3个水质指标的逐日水质数据及逐日净下泄流量,分析3个水质指标的时段离散程度、与净下泄流量的相关性及污染物月通量估算时忽略时均离散通量引起的误差大小。结果表明,COD_(Mn)、TN、TP等3个水质指标的月内变异系数分别为0.06~0.16、0.04~0.21、0.12~0.26,远小于净下泄流量的变异系数0.21~0.76;COD_(Mn)、TP两个水质指标与径流量并不存在明显的同向变化趋势,而TN与径流量具有较显著的同向变化趋势;各污染物逐月通量的时均离散误差不大,若无法获取逐日流量和逐日水质数据,采用月均流量和水质资料计算污染物通量也可以得到较准确估值。

关键词：离散通量误差钱塘江河口

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Challenges and countermeasures for developing countries in addressing loss and damage caused by climate change

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Advances in Climate Change Research 2024年第2期15卷 353-363页

作者： Shuo liU Yu-E li Bin WANG An-Dong CAI Chao FENG hua LAN ruo-Chen ZHAO Institute of Environment and Sustainable Development in Agriculture Chinese Academy of Agricultural SciencesBeijing 100081China Key Laboratory of Agricultural Environment Ministry of Agriculture and Rural AffairsBeijing 100081China China Clean Development Mechanism Fund Management Center Beijing 100045China School of International Law China University of Political Science and LawBeijing 100088China

Loss and damage caused by extreme climate events have attracted increasing *** 28th Conference of the Parties to the United Nations Framework Convention on Climate Change(hereinafter referred to as the Convention)has agreed to adopt Loss and Damage Fund agreement,which identified the source of funding and the funds to be entrusted to the World ***,there is still ambiguous that how to allocate the funds could accelerate the effectiveness of meeting the needs for developing ***-disaster prevention and preparedness is one of the most effective measures to deal with loss and damage,which closely related to *** studies rarely analyzed quantitatively the financial needs of pre-disaster prevention and preparedness relating to adaptation to reduce loss and *** on the official reports submitted by countries under the Convention,this study analyzes the annual change in the total financial support provided by developed countries to developing countries,the proportion of pre-disaster prevention and preparedness in the adaptation needs of developing countries,and the progress in raising the current annual funding target of 100 billion USD for developed countries,to reveal the financial and technical challenges facing by developing countries on addressing loss and *** results show that by 2030,the total adaptation financial needs of developing countries are estimated to be about 3.8 trillion USD,of which pre-disaster prevention matters account for about 9%.Therefore,by 2030,developing countries will need about 342 billion USD in pre-disaster prevention and preparedness finance to withstand loss and *** addition,developing countries face a lack of technical methods to quantify information about their *** on the above analysis,this study puts forward countermeasures and suggestions,including strengthening the allocation amount of loss and damage fund on pre-disaster warning,prevention and control actions,and

关键词： Loss and damage Funding mechanism Pre-disaster warning and preparedness Convention negotiations Countermeasures

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Improving anammox activity and reactor start-up speed by using CO_(2)/NaHCO_(3) buffer

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Journal of Environmental Sciences 2024年第5期139卷 60-71页

作者： Shaoan Cheng huahua li Xinyuan He hua Chen Longxin li State Key Laboratory of Clean Energy Utilization College of Energy EngineeringZhejiang UniversityHangzhou 310027China

Anammox bacteria grow slowly and can be affected by large pH *** suitable buffers could make the start-up of anammox reactors easy and *** this study,the effects of three kinds of buffers on the nitrogen removal and growth characteristics of anammox sludge were *** with CO_(2)/NaHCO_(3)buffer solution(CCBS)performed the best in nitrogen removal,while 4-(2-hydroxyerhyl)piperazine-1-ethanesulfonic acid(HEPES)and phosphate buffer solution(PBS)inhibited the anammox *** with 50 mmol/L CCBS could start up in 20 days,showing the specific anammox activity and anammox activity of 1.01±0.10 gN/(gVSS·day)and 0.83±0.06 kgN/(m^(3)·day),*** Kuenenia was the dominant anammox bacteria,with a relative abundance of 71.8%.Notably,anammox reactors could also start quickly by using 50 mmol/L CCBS under nonstrict anaerobic *** findings are meaningful for the quick start-up of engineered anammox reactors and prompt enrichment of anammox bacteria.

关键词： Anammox bacteria Buffer solution CO_(2)/NaHCO_(3) Physiological characteristics Microbial community shift

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Electrochemical filtration for drinking water purification:A review on membrane materials,mechanisms and roles

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Journal of Environmental Sciences 2024年第7期141卷 102-128页

作者： Yuying Qi Donghao li Shixuan Zhang Fengxiang li Tao hua College of Environmental Science and Engineering Nankai UniversityTianjin 300350China Key Laboratory of Pollution Process and Environmental Criteria Ministry of EducationTianjin 300350China Tianjin Engineering Center of Environmental Diagnosis and Contamination Remediation Tianjin 300350China

Electrochemical filtration can not only enrich low concentrations of pollutants but also produce reactive oxygen species to interact with toxic pollutants with the assistance of a power supply,making it an effective strategy for drinking water *** addition,the application of electrochemical filtration facilitates the reduction of pretreatment procedures and the use of chemicals,which has outstanding potential for maximizing process simplicity and reducing operating costs,enabling the production of safe drinking water in smaller *** recent years,the research on electrochemical filtration has gradually increased,but there has been a lack of attention on its application in the removal of low concentrations of pollutants from low conductivity *** this review,membrane substrates and electrocatalysts used to improve the performance of electrochemical membranes are briefly ***,the application prospects of emerging single-atom catalysts in electrochemical filtration are also ***,several electrochemical advanced oxidation processes coupled with membrane filtration are described,and the related working mechanisms and their advantages and shortcomings used in drinking water purification are ***,the roles of electrochemical filtration in drinking water purification are presented,and the main problems and future perspectives of electrochemical filtration in the removal of low concentration pollutants are discussed.

关键词： Electrochemical filtration Drinking water Conductive membrane Low concentration Electrocatalyst

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Endoscopic ultrasonography-related diagnostic accuracy and clinical significance on small rectal neuroendocrine neoplasms

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World Journal of Gastroenterology 2024年第7期30卷 774-778页

作者： Jun Weng Yu-Fan Chen Shu-Han li Yan-hua Lv ruo-Bing Chen Guo-liang Xu Shi-Yong lin Kun-Hao Bai Department of Endoscopy Sun Yat-Sen University Cancer CenterGuangzhou 510060Guangdong ProvinceChina State Key Laboratory of Oncology in South China Guangzhou 510060Guangdong ProvinceChina Guangdong Provincial Clinical Research Center for Cancer Guangzhou 510060Guangdong ProvinceChina Department of Management Clinical Medical College of Tianjin Medical UniversityTianjin 300000China Cancer Prevention Center Sun Yat-Sen University Cancer CenterGuangzhou 510060Guangdong ProvinceChina

This research aimed to examine the diagnostic accuracy and clinical significance of endoscopic ultrasonography(EUS)in the context of small rectal neuroendocrine neoplasms(NENs).A total of 108 patients with rectal subepithelial lesions(SELs)with a diameter of<20 mm were included in the *** diagnosis and depth assessment of EUS was compared to the histology *** prevalence of NENs in rectal SELs was 78.7%(85/108).The sensitivity of EUS in detecting rectal NENs was 98.9%(84/85),while the specificity was 52.2%(12/23).Overall,the diagnostic accuracy of EUS in identifying rectal NENs was 88.9%(96/108).The overall accuracy rate for EUS in assessing the depth of invasion in rectal NENs was 92.9%(78/84).Therefore,EUS demonstrates reasonable diagnostic accuracy in detecting small rectal NENs,with good sensitivity but inferior *** may also assist physicians in assessing the depth of invasion in small rectal NENs before endoscopic excision.

关键词： Rectal neuroendocrine neoplasms Endoscopic ultrasonography Diagnosis Depth of invasion

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Optimal Model Average Prediction in Orthogonal Kriging Models

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Journal of Systems Science & Complexity 2024年第3期37卷 1080-1099页

作者： WANG Jun HE Jiabei liANG hua li Xinmin School of Mathematics and Statistics Qingdao UniversityQingdao 266071China Department of Statistics George Washington UniversityWashington DC 20052USA

The main objective of this paper is to consider model averaging methods for kriging *** paper proposes a Mallows model averaging procedure for the orthogonal kriging model and demonstrate the asymptotic optimality of the model averaging estimators in terms of mean square *** studies are conducted to evaluate the performance of the proposed method and compare it with the competitors to demonstrate its *** authors also analyse a real dataset for an illustration.

关键词： Asymptotic optimality Mallows criterion optimal model averaging orthogonal kriging model

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A New Solution to Intrusion Detection Systems Based on Improved Federated-Learning Chain

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Computers, Materials & Continua 2024年第6期79卷 4491-4512页

作者： Chunhui li hua Jiang School of Computer and Electronic Information Guangxi UniversityNanning530000China Cyber Security and Information Center Guangxi UniversityNanning530000China

In the context of enterprise systems,intrusion detection(ID)emerges as a critical element driving the digital transformation of *** systems spanning various sectors of enterprises geographically dispersed,the necessity for seamless information exchange has surged *** existing cross-domain solutions are challenged by such issues as insufficient security,high communication overhead,and a lack of effective update mechanisms,rendering them less feasible for prolonged application on resource-limited *** study proposes a new cross-domain collaboration scheme based on federated chains to streamline the server-side *** this framework,individual nodes solely engage in training local data and subsequently amalgamate the final model employing a federated learning algorithm to uphold enterprise systems with efficiency and *** curtail the resource utilization of blockchains and deter malicious nodes,a node administration module predicated on the workload paradigm is introduced,enabling the release of surplus resources in response to variations in a node’s contribution *** encountering an intrusion,the system triggers an alert and logs the characteristics of the breach,facilitating a comprehensive global update across all nodes for collective *** results across multiple scenarios have verified the security and effectiveness of the proposed solution,with no loss of its recognition accuracy.

关键词： Cross-domain collaboration blockchain federated learning contribution value node management release slack resources

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Acute suppurative terminal cholangitis:Clinical characteristics of a new subtype of acute cholangitis

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Hepatobiliary & Pancreatic Diseases International 2024年第3期23卷 293-299页

作者： Rong-Tao Zhu Ye li Chi-Xian Zhang Wei-Jie Wang ruo-Peng liang Jian li Kai Bai Yu-ling Sun Department of Hepatobiliary and Pancreatic Surgery the First Affiliated Hospital of Zhengzhou UniversityZhengzhou 450052China Zhengzhou Key Laboratory of Hepatobiliary and Pancreatic Diseases Zhengzhou 450052China Institute of Hepatobiliary and Pancreatic Diseases Zhengzhou UniversityZhengzhou 450052China Department of Pathology the First Affiliated Hospital of Zhengzhou UniversityZhengzhou 450052China

Background:Acute suppurative terminal cholangitis(ASTC)is rarer than acute obstructive cholangitis and is not well *** explore this subtype of acute cholangitis,we described our clinical experience with ***:We performed a retrospective review of patients with ASTC admitted to our center from September 2014 to August *** analyzed their clinical characteristics,including etiology,clinical manifestations,imaging features,treatment and ***:A total of 32 ASTC patients were included in the *** majority of the patients had a history of biliary operations,and clinical manifestations were occult and *** positive rate of bacterial culture was 46.9%.All the patients had typical imaging features on computed tomography and magnetic resonance *** with effective antibiotics was provided as soon as diagnosis was *** treatment,most patients had a good *** levels of total bilirubin,aspartate aminotransferase,procalcitonin and gamma-glutamyltransferase were the characteristics of critically ill patients and were associated with relatively poor ***:Our results demonstrated that ASTC should be recognized as a new subtype of acute cholangitis,and that earlier diagnosis and more personalized treatments are needed.

关键词： Acute suppurative terminal cholangitis Acute cholangitis Gram-negative bacterial infections Diagnosis Treatment

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Finite-time composite learning control for nonlinear teleoperation systems under networked time-varying delays

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Science China(Information Sciences) 2024年第6期67卷 279-296页

作者： Yana YANG Huixin JIANG Changchun hua Junpeng li Institute of Electrical Engineering Yanshan University

The robust finite-time synchronization control problem is investigated for master-slave networked nonlinear telerobotics systems(NNTSs) in this article. Although there have been some research achievements on finite-time control for the NNTSs, these studies are based on the strong assumptions of communication time delays or can only achieve finite-time bounded convergence even when the external forces are *** and in view of the importance of these issues, a novel robust composite learning adaptive control scheme rendering the finite-time master-slave synchronization is proposed in this paper. In particular, the influence of time delays on finite-time convergence of the system is analyzed by employing the multi-dimension finite-time small-gain framework. Meanwhile, in order to achieve accurate and fast estimation of uncertain parameters of the system, both the online historical and the instantaneous data of the estimation data are explored to derive the new parameter adaptive law under a more realizable interval-excitation(IE) ***, the convergence of the position/force synchronization errors and the adaptive parameter estimation errors is obtained in finite time, and enhanced robustness of the closed-loop system will also be ***, the superior performance of the proposed control algorithms is validated by numerical simulations and hardware experiments.

关键词： networked teleoperation systems finite-time control exact parameter estimation small-gain theorem unknown communication delays

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