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Satellite observations of coastal upwelling in the northern Arafura Sea

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Journal of Oceanology and Limnology 2024年第2期42卷 361-376页

作者： Zheyuan YU Zhanjiu HAO Zhenhua xu Peiwen ZHANG Jia YOU Baoshu yin Hongwei YANG College of Mathematics and System Science Shandong University of Science and TechnologyQingdao 266590China CAS Key Laboratory of Ocean Circulation and Waves Institute of OceanologyChinese Academy of SciencesQingdao 266071China Pilot National Laboratory for Marine Science and Technology(Qingdao) Qingdao 266237China Center for Ocean Mega-Science Chinese Academy of SciencesQingdao 266071China University of Chinese Academy of Sciences Beijing 100049China CAS Engineering Laboratory for Marine Ranching Institute of OceanologyChinese Academy of SciencesQingdao 266071China

Coastal upwelling is significant for marine ecosystems by lifting nutrient-rich deep waters into the euphotic zone,thereby increasing primary and secondary *** satellite observations show that the northern Arafura Sea(NAS),especially in the coastal region,features high chlorophyll-a(chl-a)concentrations,implying a strong coastal ***,coastal upwelling in the NAS has not received much *** on a semi-automatic image processing technology,the seasonal and interannual variability of coastal upwelling in the NAS are investigated in this study using satellite-observed sea surface temperature(SST)and wind *** results suggest that there are seasonal coastal upwelling events in the NAS modulated by upwelling-favorable southeast monsoon(SEM).The annual mean days,mean area,and annual mean intensity of coastal upwelling events during the SEM season are 92 days,6514 km^(2),and-5.31×10^(5),respectively,while the corresponding values during the northwest monsoon(NWM)season are 32 days,5569 km^(2),and-1.41×10^(5).It is also found that the SEM coastal upwelling in the NAS displays prominent interannual *** strong upwelling events are found in 2010,2013,2016,and 2017 when the southeast monsoon winds were *** analysis suggests that at the interannual scale,the upwelling index(UI)averaged in the SEM season is negatively correlated with that of three upwelling *** can be attributed to the limitation of onshore geostrophic flow which is evidenced by the negative correlation between the UI and the alongshore difference in sea surface *** study highlights the important role of the southeast monsoon in the temporal variability of coastal upwelling in the NAS.

关键词： coastal upwelling the northern Arafura Sea southeast monsoon interannual variability

Hydrocarbon Charging and Accumulation Process of the Large Bozhong19-6 Condensate Gas Reservoirs in the Southwestern Bozhong Sub-Basin,Bohai Bay Basin,China

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Journal of Earth Science 2024年第2期35卷 613-630页

作者： Quanyun Miao Changgui xu Fang Hao Minjunshi Xie Qi Wang Jie yin Huayao Zou General Prospecting Institute of China National Administration of Coal Geology Beijing100039China State Key Laboratory of Petroleum Resource and Prospecting China University of PetroleumBeijing102249China Tianjin Branch of China National Offshore Oil Company Ltd. Tianjin300452China School of Geosciences China University of PetroleumQingdao266580China School of Geosciences Yangtze UniversityWuhan430100China

The Bozhong19-6(BZ19-6)condensate gas reservoirs,located in the southwestern Bozhong sub-basin,Bohai Bay Basin,China,were paleo-oil reservoirs in the geological past and have undergone at least three successive hydrocarbon charging *** hydrocarbon migration and accumulation process of“early oil and late gas”has occurred in the current *** the end of the sedimentation of the Guantao Formation(N_(1)g,∼12 Ma),the reservoirs began to fill with first stage low-moderate mature crude *** the late stage of the Lower Minghuazhen Formation(N_(1)ml)(∼6.7 Ma),the reservoirs were largely charged with second stage high mature crude *** the deposition of the upper Minghuazhen Formation(N_(2)m^(u),∼5.1 Ma),the paleo-oil reservoirs were transformed into shallow Neogene reservoirs due to the reactivation of basement *** the late stage of the N_(2)m^(u)to the present day(∼2.8–0 Ma),the reservoirs were rapidly filled by natural gas within a short *** addition,analysis of the formation of the reservoir bitumen and the conspicuous loss of the lower molecular weight n-alkanes in the crude oil reveal that the injection of a large amount of gas in the late stage caused gas flushing of the early charged oil.

关键词： Bohai Bay Basin BZ19-6 condensate gas reservoirs fluid inclusions hydrocarbon charging and accumulation petroleum geology

Transmission Energy Allocation for Over-the-Air Computation with Energy Harvesting

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Journal of Communications and Information Networks 2024年第2期9卷 126-136页

作者： Siyao Zhang Zixiang Ren Xinmin Li yin Long Jie xu Shuguang Cui School of Computer Science and Technology Southwest University of Science and TechnologyMianyang 621010China Shenzhen Future Network of Intelligence Institute(FNii-Shenzhen) The Chinese University of Hong KongShenzhenGuangdong 518172China School of Information Science and Technology University of Science and Technology of ChinaHefei 230027China FNii-Shenzhen The Chinese University of Hong KongShenzhenGuangdong 518172China College of Computer Science Chengdu UniversityChengdu 610100China School of Science and Engineering FNii-Shenzhenand Guangdong Provincial Key Laboratory of Future Networks of IntelligenceThe Chinese University of Hong KongShenzhenGuangdong 518172China

Over-the-air computation(AirComp)has recently emerged as a promising multiple-access technique for fast wireless data aggregation(WDA)from distributed wireless devices(WDs). This paper investigates an energy harvesting (EH) AirComp system, in which multiple EH-powered single-antenna WDs simultaneously send wireless signals to a single-antenna access point (AP) with conventional energy supply for WDA via AirComp. Under this setup, we minimize the average computation mean square error(MSE)over a particular time period, by jointly optimizing the transmit energy allocation at the WDs and the AirComp denoising factors at the AP over time, subject to the energy causality constraints at individual WDs. First, we consider the offline scenario by assuming that the energy state information(ESI)and channel state information (CSI) are non-causally known at the beginning of the period, in which the formulated average MSE minimization corresponds to a non-convex optimization problem. We present a high-quality converged solution by using the techniques of alternating optimization and convex optimization. It is shown that for each WD,if the EH rate is sufficiently high,then the channel inversion power allocation is adopted;while if the EH rate is low, then all the harvested energy should be used up for transmission with proper energy allocation over time. Next, we consider the online scenario with causal ESI and CSI,in which the MSE minimization becomes a stochastic optimization *** this scenario, we present an offline-inspired online algorithm to obtain efficient online energy allocation designs by utilizing the obtained offline solutions. Finally,numerical results show that the proposed designs significantly outperform two benchmark schemes with power-halving and full-power transmission,respectively.

关键词： over-the-air computation(AirComp) power allocation energy harvesting(EH) optimization

Impact of well placement and flow rate on production efficiency and stress field in the fractured geothermal reservoirs

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Deep Underground Science and Engineering 2024年第3期3卷 358-368页

作者： Xinghui Wu Meifeng Cai xu Wu Ketong Zhang Ziqing yin Yu Zhu School of City and Architecture Engineering Zaozhuang UniversityZaozhuangChina School of Civil and Resource Engineering University of Science and Technology BeijingBeijingChina Beijing Municipal Engineering Research Institute BeijingChina Department of Civil and Environmental Engineering University of StrathclydeGlasgowUK

Geothermal energy has gained wide attention as a renewable alternative for mitigating greenhouse gas *** advancements in enhanced geothermal system technology have enabled the exploitation of previously inaccessible geothermal ***,the extraction of geothermal energy from deep reservoirs poses many challenges due to high‐temperature and high‐geostress *** factors can significantly impact the surrounding rock and its fracture formation.A comprehensive understanding of the thermal–hydraulic–mechanical(THM)coupling effect is crucial to the safe and efficient exploitation of geothermal *** study presented a THM coupling numerical model for the geothermal reservoir of the Yangbajing geothermal *** proposed model investigated the geothermal exploitation performance and the stress distribution within the reservoir under various combinations of geothermal wells and mass flow *** geothermal system performance was evaluated by the criteria of outlet temperature and geothermal *** results indicate that the longer distance between wells can increase the outlet temperature of production wells and improve extraction efficiency in the short *** contrast,the shorter distance between wells can reduce the heat exchange area and thus mitigate the impact on the reservoir stress.A larger mass flow rate is conducive to the production capacity enhancement of the geothermal system and,in turn causes a wider range of stress *** findings provide valuable insights into the optimization of geothermal energy extraction while considering reservoir safety and long‐term *** study deepens the understanding of the THM coupling effects in geothermal systems and provides an efficient and environmentally friendly strategy for a geothermal energy system.

关键词： geothermal exploitation performance geothermal reservoir mass flow rate stress field well placementa

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An improved analysis method for assessing the nuclear-heating impact on the stability of toroidal field magnets in fusion reactors

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Nuclear Science and Techniques 2024年第6期35卷 163-176页

作者： Yu-Dong Lu Jin-Xing Zheng xu-Feng Liu Huan Wu Jian Ge Kun xu Ming Li hai-Yang Liu Lei Zhu Fei Liu Institute of Plasma Physics Hefei Institutes of Physical ScienceChinese Academy of SciencesHefei 230031China University of Science and Technology of China Hefei 230026China

The superconducting magnet system of a fusion reactor plays a vital role in plasma confinement,a process that can be dis-rupted by various operational factors.A critical parameter for evaluating the temperature margin of superconducting magnets during normal operation is the nuclear heating caused by D-T *** study investigates the impact of nuclear heat-ing on a superconducting magnet system by employing an improved analysis method that combines neutronics and thermal *** the magnet system,toroidal field(TF)magnets are positioned closest to the plasma and bear the highest nuclear-heat load,making them prime candidates for evaluating the influence of nuclear heating on *** enhance the modeling accuracy and facilitate design modifications,a parametric TF model that incorporates heterogeneity is established to expedite the optimization design process and enhance the accuracy of the computations.A comparative analysis with a homogeneous TF model reveals that the heterogeneous model improves accuracy by over 12%.Considering factors such as heat load,magnetic-field strength,and cooling conditions,the cooling circuit facing the most severe conditions is selected to calculate the temperature of the *** selection streamlines the workload associated with thermal-hydraulic *** approach enables a more efficient and precise evaluation of the temperature margin of TF ***,it offers insights that can guide the optimization of both the structure and cooling strategy of superconducting magnet systems.

关键词： Superconducting magnet Nuclear heating Neutronics Thermal hydraulics

Remote copper-catalyzed enantioselective substitution of yne-thiophene carbonates

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Science China Chemistry 2024年第4期67卷 1175-1180页

作者： Hao-Dong Qian Xiang Li Tingrui yin Wei-Feng Qian Chunhui Zhao Cuiju Zhu Hao xu CCNU-uOttawa Joint Research Centre Key Laboratory of Pesticides&Chemical Biology of Ministry of EducationInternational Joint Research Center for Intelligent Biosensing Technology and HealthCollege of ChemistryCentral China Normal UniversityWuhan 430079China

Here,we describe a strategy for the copper-catalyzed asymmetric heteroarylation of yne-thiophene carbonates with indoles via remote *** key to the success of this strategy lies in the design of the alkynyl group at the ortho-position of the heterocycle thiophene,enabling the formation of a triarylmethane moiety via very remote ***,the concept of remote copper-catalyzed asymmetric transformation extends not only to yne-allylic esters but also to yne-aryl *** reaction readily provides a diverse array of chiral triarylmethanes with high efficiency,enantioselectivity,and excellent functional group ***,facile follow-up transformations underscore their potential utility in the synthesis of various enantioenriched building *** mechanistic studies support the plausibility of the remote substitution pathway.

关键词： remote substitution copper catalyst asymmetric catalysis triaryl methanes

教师自我教育理论在中小学教育科研实践中的作用

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河北师范大学学报（教育科学版） 2012年第8期14卷 26-29页

作者：许银海宗树兴河北省教育科学研究所河北石家庄050061

教师专业成长的重要路径是能够扎实的从事教育科研活动,而专业成长的一个重要环节就是形成教师的自我教育理论,这两者之间相辅相成,互为支撑。当今中小学教育科研实践中存在着的质量不高,选题不准,研究不规范等不足,基本上都与教师自我... 详细信息

教师专业成长的重要路径是能够扎实的从事教育科研活动,而专业成长的一个重要环节就是形成教师的自我教育理论,这两者之间相辅相成,互为支撑。当今中小学教育科研实践中存在着的质量不高,选题不准,研究不规范等不足,基本上都与教师自我教育理论建设和形成的欠缺有关。在教师专业成长的实践中,要关注教师自我教育理论形成,同时更要关注其在中小学教育科研实践的应用,明确其作用的范围和重点,反过来再丰富和发展教师自我教育理论。

关键词：教师自我教育理论中小学教育科研课题研究

Towards Domain-agnostic Depth Completion

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Machine Intelligence Research 2024年第4期21卷 652-669页

作者： Guangkai xu Wei yin Jianming Zhang Oliver Wang Simon Niklaus Simon Chen Jia-Wang Bian Zhejiang University Hangzhou 310058China DaJiang Technology Shenzhen 518057China Adobe Research California 95110USA University of Oxford Oxford OX12JDUK

Existing depth completion methods are often targeted at a specific sparse depth type and generalize poorly across task *** present a method to complete sparse/semi-dense,noisy,and potentially low-resolution depth maps obtained by various range sensors,including those in modern mobile phones,or by multi-view reconstruction *** method leverages a data-driven prior in the form of a single image depth prediction network trained on large-scale datasets,the output of which is used as an input to our *** propose an effective training scheme where we simulate various sparsity patterns in typical task *** addition,we design two new benchmarks to evaluate the generalizability and robustness of depth completion *** simple method shows superior cross-domain generalization ability against state-of-the-art depth completion methods,introducing a practical solution to highqualitydepthcapture onamobile device.

关键词： Monocular depth estimation depth completion zero-shot generalization scene reconstruction neural network.

Evaluating a river's ecological health: A multidimensional approach

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Environmental Science and Ecotechnology 2024年第5期21卷 268-277页

作者： Qiuyun Zhao Yangyang Zhang Xiuwen Li Xiaodong Hu Rui Huang Jixiong xu Zilong yin Xinjie Gu Yuncheng xu Jinbao yin Qing Zhou Aimin Li Peng Shi State Key Laboratory of Pollution Control and Resource Reuse School of EnvironmentNanjing UniversityNanjing210023China Jiangsu Hydraulic Research Institute Nanjing210023China

Evaluating the health of river surface water is essential,as rivers support significant biological resources and serve as vital drinking water *** the Water Quality Index(WQI)is commonly employed to evaluate surface water quality,it fails to consider biodiversity and does not fully capture the ecological health of *** we show a comprehensive assessment of the ecological health of surface water in the lower Yangtze River(LYR),integrating chemical and biological *** to traditional WQI metrics,the LYR's surface water generally meets China's Class II ***,it also contains 43 high-risk emerging contaminants;nitrobenzenes are found at the highest concentrations,representing 25e90%of total detections,while polycyclic aromatic hydrocarbons present the most substantial environmental risks,accounting for 81e93%of the total risk ***,the plankton-based index of biological integrity(P-IBI)rates the ecological health of the majority of LYR water samples(59.7%)as‘fair’,with significantly better health observed in autumn compared to other seasons(p<0.01).Our findings suggest that including emerging contaminants and P-IBI as additional metrics can enhance the traditional WQI analysis in evaluating surface water's ecological *** results highlight the need for a multidimensional assessment approach and call for improvements to LYR's ecological health,focusing on emerging contaminants and biodiversity rather than solely on reducing conventional indicators.

关键词： The lower reaches of the Yangtze River High-risk emerging contaminants Plankton Ecological risk Biological integrity