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Analysis of dipole noise level characteristics of NACA0015 hydrofoil under different working conditions

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Journal of Hydrodynamics 2021年第1期33卷 63-73页

作者： An Yu Yi-fu Wang Qing-hong tang Da-qing Zhou College of Energy and Electrical Engineering Hohai UniversityNanjing 210098China College of Water Conservancy and Hydropower Engineering Hohai UniversityNanjing 210098China

In this paper,the flow field around NACA0015 hydrofoil is calculated under the condition of two-phase cavitating flow to provide a theoretical guidance for reducing the cavitation noise.A modified turbulence model coupled with the Zwart cavitation model is used to calculate the flow *** to the computed sound source data,the dipole sound pressure distribution diagrams for the extremely short time and the complete time around the hydrofoil under different working conditions are *** sound pressure distribution and the sound pressure amplitude are analyzed in *** addition,the field points around the hydrofoil are selected to generate the corresponding frequency response function curves,which are analyzed from the aspects of the trend,the variation and the extreme *** results show that the dipole characteristics are gradually diminished and finally disappear with the increase of the *** the frequency of the vapor volume fraction fluctuation,the noise level at the field point will have an extreme value.

关键词： Cavitating flow dipole noise sound field distribution frequency response

Formation control of bromate and trihalomethanes during ozonation of bromide-containing water with chemical addition: Hydrogen peroxide or ammonia?

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Journal of Environmental Sciences 2021年第12期33卷 111-118页

作者： Zhengdi Wu Yubin tang Weiwei Li Zhimin Qiang huiyu Dong Key Laboratory of Drinking Water Science and Technology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China School of Environmental and Chemical Engineering Jiangsu University of Science and TechnologyZhenjiang 212100China Engineering Design Institute The Sixth Engineering Bure CrecBeijing 100036China University of Chinese Academy of Sciences Beijing 100049China

To ensure the safety of drinking water,ozone (O3) has been extensively applied in drinking water treatment plants to further remove natural organic matter (NOM).However,the surface water and groundwater near the coastal areas often contain high concentrations of bromide ion (Br-).Considering the risk of bromate (Br O3-) formation in ozonation of the sand-filtered water,the inhibitory efficiencies of hydrogen peroxide (H2O2) and ammonia(NH3) on Br O3-formation during ozonation process were *** addition of H2O2effectively inhibited Br O3-formation at an initial Br-concentration amended to 350μg/*** inhibition efficiencies reached 59.6 and 100%when the mass ratio of H2O2/O3was 0.25and>0.5,*** UV254and total organic carbon (TOC) also decreased after adding H2O2,while the formation potential of trihalomethanes (THMs FP) increased especially in subsequent chlorination process at a low dose of *** control the formation of both Br O3-and THMs,a relatively large dose of O3and a high ratio of H2O2/O3were generally ***3addition inhibited Br O3-formation when the background ammonia nitrogen(NH3–N) concentration was *** was no significant correlation between Br O3-inhibition efficiency and NH3dose,and a small amount of NH3–N (0.2 mg/L) could obviously inhibit Br *** oxidation of NOM seemed unaffected by NH3addition,and the structure of NOM reflected by synchronous fluorescence (SF) scanning remained almost unchanged before and after adding *** the formation of Br O3-and THMs,the optimal dose of NH3was suggested to be 0.5 mg/L.

关键词： Bromate Trihalomethanes Ozone Hydrogen peroxide Ammonia Water treatment

自由贸易试验区新质生产力发展水平的测度与时空演变

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高师理科学刊 2025年第1期45卷 32-39页

作者：邵宇陈思吉唐耀宗喀什大学数学与统计学院新疆喀什844000

从新劳动者、新劳动对象、新劳动资料三个维度构建新质生产力发展水平综合评价指标体系,运用熵权法测算2014—2022年17个自由贸易试验区的新质生产力水平,从指标、省份以及区域层面对研究结果进行分析,并进一步运用自然断点分类法和莫... 详细信息

从新劳动者、新劳动对象、新劳动资料三个维度构建新质生产力发展水平综合评价指标体系,运用熵权法测算2014—2022年17个自由贸易试验区的新质生产力水平,从指标、省份以及区域层面对研究结果进行分析,并进一步运用自然断点分类法和莫兰指数对自由贸易试验区新质生产力的时空特征以及空间相关性进行探究.研究结果表明,自由贸易试验区新质生产力水平总体上呈现上升趋势,地区间新质生产力水平存在差异性,东部地区发展水平高,西部地区发展水平低,同时自由贸易试验区新质生产力发展呈现空间正相关性,表现为高效型和低效型集聚.

关键词：自由贸易试验区新质生产力莫兰指数空间相关性

Gene expression during different periods of the handling-stress response in Pampus argenteus

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Journal of Oceanology and Limnology 2018年第4期36卷 1349-1359页

作者： SUN Peng tang Baojun YIN Fei Key Laboratory of East China Sea Fishery Resources Exploitation Ministry of Agricultur East China Sea Fisheries Research Institute Chinese Academy of Fishery SciencesShanghai 200090China

Common aquaculture practices subject fish to a variety of acute and chronic stressors. Such stressors are inherent in aquaculture production but can adversely affect survival, growth, immune response, reproductive capacity, and behavior. Understanding the biological mechanisms underlying stress responses helps with methods to alleviate the negative effects through better aquaculture practices, resulting in improved animal welfare and production efficiency. In the present study, transcriptome sequencing of liver and kidney was performed in silver pomfret( Pampus argenteus) subjected to handling stress versus controls. A total of 162.19 million clean reads were assembled to 30 339 unigenes. The quality of the assembly was high, with an N50 length of 2 472 bases. For function classification and pathway assignment, the unigenes were categorized into three GO(gene ontology) categories, twenty-six clusters of egg NOG(evolutionary genealogy of genes: non-supervised orthologous groups) function categories, and thirty-eight KEGG(Kyoto Encyclopedia of Genes and Genomes) pathways. Stress affected different functional groups of genes in the tissues studied. Differentially expressed genes were mainly involved in metabolic pathways(carbohydrate metabolism, lipid metabolism, amino-acid metabolism, uptake of cofactors and vitamins, and biosynthesis of other secondary metabolites), environmental information processing(signaling molecules and their interactions), organismal systems(endocrine system, digestive system), and disease(immune, neurodegenerative, endocrine and metabolic diseases). This is the first reported analysis of genome-wide transcriptome in P. argenteus, and the findings expand our understanding of the silver pomfret genome and gene expression in association with stress. The results will be useful to future analyses of functional genes and studies of healthy artificial breeding in P. argenteus and other related fish species.

关键词： gene ontology immune system next-generation sequencing transcriptome unigenes

Biodegradable dissolved organic carbon shapes bacterial community structures and co-occurrence patterns in large eutrophic Lake Taihu

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Journal of Environmental Sciences 2021年第9期33卷 205-217页

作者： Lei Zhou Yongqiang Zhou Xiangming tang Yunlin Zhang Erik Jeppesen Taihu Laboratory for Lake Ecosystem Research State Key Laboratory of Lake Science and EnvironmentNanjing Institute of Geography and LimnologyChinese Academy of SciencesNanjing 210008China University of Chinese Academy of Sciences Beijing 100049China Department of Bioscience Aarhus UniversitySilkeborg 8600Denmark Sino-Danish Centre for Education and Research Beijing 100049China Limnology Laboratory Department of Biological Sciences and Centre for Ecosystem Research and ImplementationMiddle East Technical UniversityAnkara 06800Turkey Institute of Marine Sciences Middle East Technical UniversityMersinTurkey

Interactions between dissolved organic matter(DOM)and bacteria are central in the biogeochemical cycles of aquatic ecosystems;however,the relative importance of biodegradable dissolved organic carbon(BDOC)compared with other environmental variables in structuring the bacterial communities needs further ***,we investigated bacterial communities,chromophoric DOM(CDOM)characteristics and physico-chemical parameters as well as examined BDOC via bioassay incubations in large eutrophic Lake Taihu,China,to explore the importance of BDOC for shaping bacterial community structures and co-occurrence *** found that the proportion of BDOC(%BDOC)correlated significantly and positively with the DOC concentration and the index of the contribution of recent produced autochthonous CDOM(BIX).%BDOC,further correlated positively with the relative abundance of the tryptophan-like component and negatively with CDOM aromaticity,indicating that autochthonous production of protein-like CDOM was an important source of *** richness of the bacterial communities correlated negatively with%BDOC,indicating an enhanced number of species in the refractory DOC environments.%BDOC was identified as a significant stronger factor than DOC in shaping bacterial community composition and the co-occurrence network,suggesting that substrate biodegradability is more significant than DOC quantity determining the bacterial communities in a eutrophic *** factors explained a larger proportion of the variation in the conditionally rare and abundant subcommunity than for the abundant and the rare bacterial *** findings emphasize the importance of considering bacteria with different abundance patterns and DOC biodegradability when studying the interactions between DOM and bacteria in eutrophic lakes.

关键词： Biodegradable dissolved organic carbon Bacterial community Co-occurrence networks Chromophoric dissolved organic matter Habitat niche breadth

Insights into multidimensional transport flux from vertical observation and numerical simulation in two cities in North China

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Journal of Environmental Sciences 2023年第3期125卷 831-842页

作者： Zhida Zhang Xiaoqi Wang Shuiyuan Cheng Guiqian tang Yibin Fu Key Laboratory of Beijing on Regional Air Pollution Control Beijing University of TechnologyBeijing 100124China State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry(LAPC) Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China Key Laboratory of Environmental Optics and Technology Anhui Institute of Optics and Fine MechanicsHefei Institutes of Physical ScienceChinese Academy of SciencesHefei 230031China

This study represents the first quantitative evaluation of pollution transport budget within the boundary layer of typical cities in the Beijing-Tianjin-Hebei (BTH) region from the perspective of horizontal and vertical exchanges and further discusses the impact of the atmospheric boundary layer (ABL)-free troposphere (FT) exchange on concentration of fine particulate matter (PM_(2.5)) within the ABL during heavy *** the perspective of the transport flux balance relationship,differences in pollution transport characteristics between the two cities is mainly reflected in the ABL-FT exchange *** FT mainly flowed into the ABL in BJ,while in SJZ,the outflow from the ABL to the FT was more *** with an analysis of vertical wind profile distribution,BJ was found to be more susceptible to the influence of northwest cold high prevailing in winter,while sinking of strong cold air allowed the FT flowing into the ABL influence the vertical exchange over *** addition,we selected a typical pollution event for targeted analysis to understand mechanistic details of the influence of ABL-FT exchange on the pollution *** results showed that ABL-FT interaction played an important role in PM_(2.5)concentration within the ABL during heavy *** in the early stage of heavy pollution,FT transport contributed as much as 82.74% of PM_(2.5)within the *** findings are significant for improving our understanding of pollution transport characteristics within the boundary layer and the effect of ABL-FT exchange on air quality.

关键词： Transport flux Horizontal transport Vertical exchange Atmospheric boundary layer Free troposphere Pollutant budget relationship

Transient Behaviors of Thermo-Hydraulic and Thermal Stratification in the Pressurizer Surgeline for the Nuclear Power Plant

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Journal of Thermal Science 2022年第2期31卷 344-358页

作者： YU Huajie LI Lu tang Qionghui PENG Yue LI Yinshi State Key Laboratory of Nuclear Power Safety Monitoring Technology and Equipment Shenzhen 518172China Key Laboratory of Thermo-Fluid Science and Engineering of ministry of Education School of Energy and Power EngineeringXi’an Jiaotong UniversityXi’an 710049China School of Mechanics and Safety Engineering Zhengzhou UniversityZhengzhou 450001China

In pressurized water reactor(PWR)system,the surgeline plays an important role in bonding the pressurizer and the primary *** considerable problems,including the thermo-hydraulics,the thermal stratification and the accompanying thermal stress under transient conditions,pose risks to the surgeline ***,a fully-coupled flow-heat-thermo-elasticity model was developed to investigate the transient behavior of thermo-hydraulic parameters and the thermal stratification phenomenon in *** evaluate the nonuniformity of the stratified flow,a stratification degree indicatorζis *** is found that during the outsurge flow,the increase of temperature variation will enlarge the temperature gradient on the wall,corresponding to a more serious *** the cases of positive temperature variation,the higher temperature variation causes higher stratification degreeζ,and vice *** mass flow rate m and the stratification degree are in negative *** local deformation can reach 1.802 cm under a 50 K temperature variation,while its location varies from case to *** attention should be paid to the regulation between the highest deformation location and the surgeline thermo-hydraulic parameters.

关键词： pressurized water reactor surgeline transient thermo-hydraulic thermal stratification thermal stress-strain

Task Scheduling for Multi-Cloud Computing Subject to Security and Reliability Constraints

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IEEE/CAA Journal of Automatica Sinica 2021年第4期8卷 848-865页

作者： Qing-Hua Zhu Huan tang Jia-Jie Huang Yan Hou School of Computer Science and Technology Guangdong University of TechnologyGuangzhou 510006China

The rise of multi-cloud systems has been *** safety-critical missions,it is important to guarantee their security and *** address trust constraints in a heterogeneous multi-cloud environment,this work proposes a novel scheduling method called matching and multi-round allocation(MMA)to optimize the makespan and total cost for all submitted tasks subject to security and reliability *** method is divided into two phases for task *** first phase is to find the best matching candidate resources for the tasks to meet their preferential demands including performance,security,and reliability in a multi-cloud environment;the second one iteratively performs multiple rounds of re-allocating to optimize tasks execution time and cost by minimizing the variance of the estimated completion *** proposed algorithm,the modified cuckoo search(MCS),hybrid chaotic particle search(HCPS),modified artificial bee colony(MABC),max-min,and min-min algorithms are implemented in CloudSim to create *** simulations and experimental results show that our proposed method achieves shorter makespan,lower cost,higher resource utilization,and better trade-off between time and economic *** is more stable and efficient.

关键词： Multi-cloud environment multi-quality of service(QoS) reliability security task scheduling

SuperFusion: A Versatile Image Registration and Fusion Network with Semantic Awareness

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IEEE/CAA Journal of Automatica Sinica 2022年第12期9卷 2121-2137页

作者： Linfeng tang Yuxin Deng Yong Ma Jun Huang Jiayi Ma Electronic Information School Wuhan UniversityWuhan 430072China IEEE

Image fusion aims to integrate complementary information in source images to synthesize a fused image comprehensively characterizing the imaging scene. However, existing image fusion algorithms are only applicable to strictly aligned source images and cause severe artifacts in the fusion results when input images have slight shifts or deformations. In addition,the fusion results typically only have good visual effect, but neglect the semantic requirements of high-level vision *** study incorporates image registration, image fusion, and semantic requirements of high-level vision tasks into a single framework and proposes a novel image registration and fusion method, named Super Fusion. Specifically, we design a registration network to estimate bidirectional deformation fields to rectify geometric distortions of input images under the supervision of both photometric and end-point constraints. The registration and fusion are combined in a symmetric scheme, in which while mutual promotion can be achieved by optimizing the naive fusion loss, it is further enhanced by the mono-modal consistent constraint on symmetric fusion outputs. In addition, the image fusion network is equipped with the global spatial attention mechanism to achieve adaptive feature integration. Moreover, the semantic constraint based on the pre-trained segmentation model and Lovasz-Softmax loss is deployed to guide the fusion network to focus more on the semantic requirements of high-level vision tasks. Extensive experiments on image registration, image fusion,and semantic segmentation tasks demonstrate the superiority of our Super Fusion compared to the state-of-the-art *** source code and pre-trained model are publicly available at https://***/Linfeng-tang/Super Fusion.

关键词： Global spatial attention image fusion image registration mutual promotion semantic awareness