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Assessment of Future Drought in Southwest China Based on CMIP5 Multimodel Projections

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Advances in Atmospheric Sciences 2014年第5期31卷 1035-1050页

作者： WANG Lin CHEN wen zhou wen Center for Monsoon System Research Institute of Atmospheric Physics Chinese Academy of Sciences University of Chinese Academy of Sciences Guy Carpenter Asia-Pacific Climate Impact Centre School of Energy and EnvironmentCity University of Hong Kong

In the last decade, a series of severe and extensive droughts have swept across Southwest China, resulting in tremendous economic losses, deaths, and disruption to society. Consequently, this study is motivated by the paramount importance of as- sessing future changes in drought in Southwest China. Precipitation is likely to decrease over most parts of Southwest China around the beginning of the century, followed by widespread precipitation increases; the increase in potential evapotran- spiration （PET）, due to the joint effects of increased temperature and surface net radiation and decreased relative humidity, will overwhelm the whole region throughout the entire 21st century. In comparative terms, the enhancement of PET will outweigh that of precipitation, particularly under Representative Concentration Pathway （RCP） 8.5, resulting in intensified drought. Generally, the drying tendency will be in the southeast portion, whereas the mountainous region in the northwest will become increasingly wetter owing to abundant precipitation increases. Droughts classified as moderate/severe according to historical standards will become the norm in the 2080s under RCP4.5/RCP8.5. Future drought changes will manifest different characteristics depending on the time scale： the magnitude of change at a time scale of 48 months is nearly twice as great as that at 3 months. Furthermore, we will see that not only will incidences of severe and extreme drought increase dramatically in the future, but extremely wet events will also become more probable.

关键词： drought Standardized Precipitation Evapotranspiration Index spatial disaggregation Southwest China

Biomedical Named Entity Recognition Based on Self-supervised Deep Belief Network

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Chinese Journal of Electronics 2020年第3期29卷 455-462页

作者： ZHANG Yajun LIU Zongtian zhou wen Shanghai Institute of Precision Measurement and Test School of Computer Engineering and Science Shanghai University

Named entity recognition is a fundamental and crucial issue of biomedical data mining. For effectively solving this issue, we propose a novel approach based on Deep belief network(DBN). We select nine entity features, and construct feature vector mapping tables by the recognition contribution degree of different values of them. Using the mapping tables, we transform words in biomedical texts to feature vectors. The DBN will identify entities by reducing dimensions of vector *** extensive experimental results reveal that the novel approach has achieved excellent recognition performance,with 69.96% maximum value of F-measure on GENIA 3.02 testing corpus. We propose a self-supervised DBN, which can decide whether to add supervised fine-tuning or not according to the recognition performance of each layer,can overcome the errors propagation problem, while the complexity of model is limited. Test analysis shows that the new DBN improves recognition performance, the Fmeasure increases to 72.12%.

关键词： Biomedical named entity recognition Feature selection Feature vector mapping Threshold judgement Self-supervision

Statistical Modeling and Trend Detection of Extreme Sea Level Records in the Pearl River Estuary

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Advances in Atmospheric Sciences 2017年第3期34卷 383-396页

作者： Weiwen WANG wen zhou School of Architecture The Chinese University of Hong KongHong KongChina Guy Carpenter Asia-Pacific Climate Impact Centre School of Energy and EnvironmentCity University of Hong KongHong KongChina City University ofHong Kong Shenzhen Research Institute Shenzhen 518057China

Sea level rise has become an important issue in global climate change studies. This study investigates trends in sea level records, particularly extreme records, in the Pearl River Estuary, using measurements from two tide gauge stations in Macao and Hong Kong. Extremes in the original sea level records （daily higher high water heights） and in tidal residuals with and without the 18.6-year nodal modulation are investigated separately. Thresholds for defining extreme sea levels are calibrated based on extreme value theory. Extreme events are then modeled by peaks-over-threshold models. The model applied to extremes in original sea level records does not include modeling of their durations, while a geometric distribution is added to model the duration of extremes in tidal residuals. Realistic modeling results are recommended in all stationary models. Parametric trends of extreme sea level records are then introduced to nonstationary models through a generalized linear model framework. The result shows that, in recent decades, since the 1960s, no significant trends can be found in any type of extreme at any station, which may be related to a reduction in the influence of tropical cyclones in the region. For the longer-term record since the 1920s at Macao, a regime shift of tidal amplitudes around the 1970s may partially explain the diverse trend of extremes in original sea level records and tidal residuals.

关键词： sea level rise extreme climate change extreme value theory Pearl River Estuary

Physical mechanism of the rapid increase in intense and long-lived extreme heatwaves in the Northern Hemisphere since 1980

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Science China Earth Sciences 2024年第7期67卷 2103-2121页

作者： Yuqing WANG wen zhou Chunzai WANG Key Laboratory of Polar Atmosphere-ocean-ice System for Weather and Climate of the MOE Department of Atmospheric and Oceanic Sciences&Institute of Atmospheric SciencesFudan UniversityShanghai 200438China Key Laboratory for Polar Science of the MNR Polar Research Institute of ChinaShanghai 201209China State Key Laboratory of Tropical Oceanography South China Sea Institute of OceanologyChinese Academy of SciencesGuangzhou 510301China Global Ocean and Climate Research Center South China Sea Institute of OceanologyChinese Academy of SciencesGuangzhou 510301China

Since 1980,both the intensity and duration of summer heatwaves in the middle and high latitudes of the Northern Hemisphere have significantly increased,leading this region to become a critical area for a significant increase in the frequency of intense and long-lived extreme *** found that stronger and more persistent high-pressure systems and lower soil moisture before the events were the main drivers of intense and long-lived extreme heatwaves in western Europe and the middle and high latitudes of North ***,in eastern Europe and Siberia,lower cloud cover before events is also a main driver of this type of extreme heatwave,in addition to the above *** factors are coupled with each other and can change heatwave intensity and duration by influencing surface radiation processes during *** the self-organizing map classification method,we found that 6 weather patterns with increased frequency,intensity,and duration were the main dynamic reasons leading to the increase in intense and long-lived extreme heatwaves after *** addition,the decrease in summer average soil moisture in most areas of the mid-high latitudes of the Northern Hemisphere and the decrease in average cloud cover in eastern Europe and Siberia are found to be the main thermodynamic reasons leading to the increase in these extreme heatwaves.

关键词： High intensity Long duration Extreme heatwaves High pressure system Soil moisture Cloud cover

Adsorbed and free gas occurrence characteristics and controlling factors of deep shales in the southern Sichuan Basin,China

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Petroleum Science 2023年第3期20卷 1301-1311页

作者： Shang-wen zhou Dong-Xiao Zhang Department of Energy and Resources Engineering College of EngineeringPeking UniversityBejing100871China PetroChina Research Institute of Petroleum Exploration and Development Beijing100083China School of Environmental Science and Engineering Southern University of Science and TechnologyShenzhenGuangdong 518055China

Deep shale gas(3500-4500 m)will be the important succeeding field for the growth of shale gas production in *** the condition of high temperature and high pressure in deep shale gas reservoirs,its gas occurrence characteristics are markedly different from those of medium and shallow *** elucidate the gas occurrence characteristics and controlling factors of deep shales in the Wufeng-Longmaxi Formation,methane adsorption,low-temperature N2,and cO2 adsorption experi-ments were *** results show that in deep shales,the mesopores provide approximately 75%of the total specific surface area(SA)and 90%of the total pore volume(PV).Based on two hypotheses and comparing the theoretical and actual adsorption capacity,it is speculated that methane is adsorbed in deep shale in the form of micropore filling,and free gas is mainly stored in the *** analysis demonstrated that ToC is the key material constraint for the adsorption capacity of deep shale,and micropore SSA is the key spatial *** minerals and mesopore parameters have limited effect on the amount of adsorbed ***,the free gas content ranges from 2.72 m^(3)/t to 6.20 m^(3)/t,with an average value of 4.60 m^(3)/t,and the free gas content ratio is approximately 58%,suggesting that the deep shale gas reservoirs are dominated by free *** ratio may also increase to approximately 70%when considering the formation temperature effect on adsorbed *** density,porosity,and gas saturation are the main controlling factors of free gas content,resulting in significantly larger free gas content in deep shale than in shallower formations.

关键词： Adsorbedgas Free gas Gas occurrence characteristics Deep shale

Construction of fault diagnosis system for control rod drive mechanism based on knowledge graph and Bayesian inference

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Nuclear Science and Techniques 2023年第2期34卷 58-75页

作者： Xue‑Jun Jiang wen zhou Jie Hou Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China University of Chinese Academy of Sciences Beijing 100049China

Knowledge graph technology has distinct advantages in terms of fault *** this study,the control rod drive mechanism(CRDM)of the liquid fuel thorium molten salt reactor(TMSR-LF1)was taken as the research object,and a fault diagnosis system was proposed based on knowledge *** subject–relation–object triples are defined based on CRDM unstructured data,including design specification,operation and maintenance manual,alarm list,and other forms of expert *** this study,we constructed a fault event ontology model to label the entity and relationship involved in the corpus of CRDM fault events.A three-layer robustly optimized bidirectional encoder representation from transformers(RBT3)pre-training approach combined with a text convolutional neural network(TextCNN)was introduced to facilitate the application of the constructed CRDM fault diagnosis graph database for fault *** RBT3-TextCNN model along with the Jieba tool is proposed for extracting entities and recognizing the fault query intent *** on the dataset collected from TMSR-LF1 CRDM fault diagnosis unstructured data demonstrate that this model has the potential to improve the effect of intent recognition and entity ***,a fault alarm monitoring module was developed based on WebSocket protocol to deliver detailed information about the appeared fault to the operator ***,the Bayesian inference method combined with the variable elimination algorithm was proposed to enable the development of a relatively intelligent and reliable fault diagnosis ***,a CRDM fault diagnosis Web interface integrated with graph data visualization was constructed,making the CRDM fault diagnosis process intuitive and effective.

关键词： CRDM Knowledge graph Fault diagnosis Bayesian inference RBT3-TextCNN Web interface

Monkeys pass the mirror test after training

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Science China(Life Sciences) 2015年第4期58卷 405-406页

作者： zhou wen JIANG Yi Key Laboratory of Mental Health Institute of Psychology Chinese Academy of Sciences CAS Center for Excellence in Brain Science Institute of Psychology Chinese Academy of Sciences State Key Laboratory of Brain and Cognitive Science Institute of Psychology Chinese Academy of Sciences

There is no experiencing without an experiencer, the self. Whether the experiencer knows it is ＂the self＂ that is experiencing is a different and tricky philosophical issue. Dating back to Ivan Pavlov＇s dogs, the ＂experience＂ of animals has been the subject of scientific research for over a century, yet to which extent different animals possess the sense of self is still hotly debated today. From human＇s perspective, the sense of self is the corner stone of feelings, thoughts, and social interactions--a necessity of higher intelligence.

关键词：测试镜子培训猴子哲学问题巴甫洛夫科学研究自我意识

Impact of Arctic amplification on East Asian winter climate

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Atmospheric and Oceanic Science Letters 2017年第5期10卷 385-388页

作者： zhou wen School of Energy and Environment City University of Hong Kong Hong Kong China

***The Arctic region warms about twice as much as the global average,and this so-called Arctic amplification（AA）might increase the moisture flux towards Siberia（Cohen et al.2014）.Furthermore,because of strong radiative cooling over Siberia in winter,AA might enhance the snowfall in that region and reinforce cold spells in East Asia（Wu,Su,and Zhang 2011）.

关键词： Arctic winter Siberia amplification autumn moisture Atlantic extreme radiative warming

Science——an important lever to tackle sustainability in the specialty chemical industry

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National Science Review 2023年第9期10卷 19-20页

作者： wen-Juan zhou Pascal Metivier Efficient Products and Processes Laboratory(E2P2L) UMI 3464 CNRS-Solvay Research & Innovation Solvay SA

Carbon neutrality by the mid-twenty-first century is essential in order to limit global warming to≤1.5℃,which is also laid down in the Paris Agreement signed by 196 countries including China,the European Union and the USA,etc.[1].The chemical industry is crucial to building a sustainable global economy to contribute to carbon neutrality.

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