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Typicality at quantum-critical points
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作者 Lu Liu Anders W Sandvik Wenan Guo 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第8期517-528,共12页
We discuss the concept of typicality of quantum states at quantum-critical points, using projector Monte Carlo simu- lations of an S ---- 1/2 bilayer Heisenberg antiferromagnet as an illustration. With the projection ... We discuss the concept of typicality of quantum states at quantum-critical points, using projector Monte Carlo simu- lations of an S ---- 1/2 bilayer Heisenberg antiferromagnet as an illustration. With the projection (imaginary) time t scaled as t= aLz, L being the system length and z the dynamic critical exponent (which takes the value z = 1 in the bilayer model studied here), a critical point can be identified which asymptotically flows to the correct location and universality class with increasing L, independently of the prefactor a and the initial state. Varying the proportionality factor a and the initial state only changes the cross-over behavior into the asymptotic large-L behavior. In some cases, choosing an optimal factor a may also lead to the vanishing of the leading finite-size corrections. The observation of typicality can be used to speed up simulations of quantum criticality, not only within the Monte Carlo approach but also with other numerical methods where imaginary-time evolution is employed, e.g., tensor network states, as it is not necessary to evolve fully to the ground state but only for sufficiently long times to reach the typicality regime. 展开更多
关键词 typicality quantum criticality bilayer Heisenberg antiferromagnet model imaginary projectingtime projecting quantum Monte Carlo simulation
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Molecular Investigation of Theileria in Ixodid Ticks from Changzhi,Shanxi Province,China
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作者 Jia Cui Hua Xiang Rao +2 位作者 Yiping Liu Dongmei Li Juan Yu 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2024年第8期922-925,共4页
Theileria is a tick-borne intracellular protozoan that typically parasitizes erythrocytes,lymphocytes,and macrophages and causes acute clinical symptoms in host animals,including high fever,anemia,jaundice,and swellin... Theileria is a tick-borne intracellular protozoan that typically parasitizes erythrocytes,lymphocytes,and macrophages and causes acute clinical symptoms in host animals,including high fever,anemia,jaundice,and swelling of superficial lymph nodes[1].Theileriosis can lead to high mortality rates,and its rising global prevalence has resulted in significant economic losses to livestock husbandry and the national economy[2]. 展开更多
关键词 HUSBANDRY SWELLING typically
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Call for knowledge systematization:An example from lithium ion batteries recycling
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作者 Yun Zhao Baohua Li 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第7期169-170,共2页
Scientific research is one of the primary ways to drive human civilization forward.Countless research institutions and researchers worldwide are dedicated to exploring the unknown,resulting in a flood of research find... Scientific research is one of the primary ways to drive human civilization forward.Countless research institutions and researchers worldwide are dedicated to exploring the unknown,resulting in a flood of research findings[1].For instance,Web of Science alone collects over 10,000 academic papers on a daily basis.While each research field typically has around 10%of review articles,these mainly focus on a limited portion of the subject,failing to provide a comprehensive and real-time updated overview.As a result,researchers or students in a particular field may spend several months,or even longer,comprehending the state of research that has developed over just a few years.The lack of systematic background often leads to redundant or similar studies,which is highly detrimental to the progress of science and technology. 展开更多
关键词 LITHIUM typically SPEND
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Dengue fever in Egypt:Current situation and future risks
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作者 Marwa Omar 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2024年第10期429-431,共3页
Dengue or dengue fever(DF)is an acute infectious disease of a febrile nature.It is caused by the dengue virus(DENV),which belongs to the family Flaviviridae and has four antigenically distinctive serotypes(DENV-1,DENV... Dengue or dengue fever(DF)is an acute infectious disease of a febrile nature.It is caused by the dengue virus(DENV),which belongs to the family Flaviviridae and has four antigenically distinctive serotypes(DENV-1,DENV-2,DENV-3 and DENV-4).DENV is regarded as one of the most prevalent fast-emerging mosquito-borne viruses,which has a wide distribution in many tropical and subtropical regions worldwide.The virus is typically transmitted following the bite of an infected female mosquito of the species,Aedes(Ae.)aegypti and Ae.albopictus[1]. 展开更多
关键词 FEVER ACUTE typically
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Improving the Accuracy of Vegetation Index Retrieval for Biomass by Combining Ground-UAV Hyperspectral Data-A New Method for Inner Mongolia Typical Grasslands
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作者 Ruochen Wang Jianjun Dong +3 位作者 Lishan Jin Yuyan Sun Taogetao Baoyin Xiumei Wang 《Phyton-International Journal of Experimental Botany》 SCIE 2024年第2期387-411,共25页
Grassland biomass is an important parameter of grassland ecosystems.The complexity of the grassland canopy vegetation spectrum makes the long-term assessment of grassland growth a challenge.Few studies have explored t... Grassland biomass is an important parameter of grassland ecosystems.The complexity of the grassland canopy vegetation spectrum makes the long-term assessment of grassland growth a challenge.Few studies have explored the original spectral information of typical grasslands in Inner Mongolia and examined the influence of spectral information on aboveground biomass(AGB)estimation.In order to improve the accuracy of vegetation index inversion of grassland AGB,this study combined ground and Unmanned Aerial Vehicle(UAV)remote sensing technology and screened sensitive bands through ground hyperspectral data transformation and correlation analysis.The narrow band vegetation indices were calculated,and ground and airborne hyperspectral inversion models were established.Finally,the accuracy of the model was verified.The results showed that:(1)The vegetation indices constructed based on the ASD FieldSpec 4 and the UAV were significantly correlated with the dry and fresh weight of AGB.(2)The comparison between measured R^(2) with the prediction R^(2) indicated that the accuracy of the model was the best when using the Soil-Adjusted Vegetation Index(SAVI)as the independent variable in the analysis of AGB(fresh weight/dry weight)and four narrow-band vegetation indices.The SAVI vegetation index showed better applicability for biomass monitoring in typical grassland areas of Inner Mongolia.(3)The obtained ground and airborne hyperspectral data with the optimal vegetation index suggested that the dry weight of AGB has the best fitting effect with airborne hyperspectral data,where y=17.962e^(4.672x),the fitting R^(2) was 0.542,the prediction R^(2)was 0.424,and RMSE and REE were 57.03 and 0.65,respectively.Therefore,established vegetation indices by screening sensitive bands through hyperspectral feature analysis can significantly improve the inversion accuracy of typical grassland biomass in Inner Mongolia.Compared with ground monitoring,airborne hyperspectral monitoring better reflects the inversion of actual surface biomass.It provides a reliable modeling framework for grassland AGB monitoring and scientific and technological support for grazing management. 展开更多
关键词 Aboveground biomass inversion model vegetation index unmanned aerial vehicle typical grassland
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Introduction to the Special Issue on ComputerModeling for Smart Cities Applications
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作者 Wenbing Zhao Chenxi Huang Yizhang Jiang 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第2期1015-1017,共3页
A significant fraction of the world’s population is living in cities. With the rapid development ofinformation and computing technologies (ICT), cities may be made smarter by embedding ICT intotheir infrastructure. B... A significant fraction of the world’s population is living in cities. With the rapid development ofinformation and computing technologies (ICT), cities may be made smarter by embedding ICT intotheir infrastructure. By smarter, we mean that the city operation will be more efficient, cost-effective,energy-saving, be more connected, more secure, and more environmentally friendly. As such, a smartcity is typically defined as a city that has a strong integration with ICT in all its components, includingits physical components, social components, and business components [1,2]. 展开更多
关键词 SMART typically SMART
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A Cascading Fault Path Prediction Method for Integrated Energy Distribution Networks Based on the Improved OPA Model under Typhoon Disasters
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作者 Yue He YaxiongYou +4 位作者 ZhianHe Haiying Lu Lei Chen Yuqi Jiang Hongkun Chen 《Energy Engineering》 EI 2024年第10期2825-2849,共25页
In recent times,the impact of typhoon disasters on integrated energy active distribution networks(IEADNs)has received increasing attention,particularly,in terms of effective cascading fault path prediction and enhance... In recent times,the impact of typhoon disasters on integrated energy active distribution networks(IEADNs)has received increasing attention,particularly,in terms of effective cascading fault path prediction and enhanced fault recovery performance.In this study,we propose a modified ORNL-PSerc-Alaska(OPA)model based on optimal power flow(OPF)calculation to forecast IEADN cascading fault paths.We first established the topology and operational model of the IEADNs,and the typical fault scenario was chosen according to the component fault probability and information entropy.The modified OPA model consisted of two layers:An upper-layer model to determine the cascading fault location and a lower-layer model to calculate the OPF by using Yalmip and CPLEX and provide the data to update the upper-layer model.The approach was validated via the modified IEEE 33-node distribution system and two real IEADNs.Simulation results showed that the fault trend forecasted by the novel OPA model corresponded well with the development and movement of the typhoon above the IEADN.The proposed model also increased the load recovery rate by>24%compared to the traditional OPA model. 展开更多
关键词 IEADNs OPA model cascading fault path prediction fault probability optimal power flow typical fault scenario
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Rare and lacking typical clinical symptoms of liver tumors:Four case reports
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作者 Yun Zhao Yu-Kun Bie +2 位作者 Guang-Ya Zhang Yi-Bin Feng Feng Wang 《World Journal of Gastrointestinal Oncology》 SCIE 2024年第10期4264-4273,共10页
BACKGROUND Rare liver tumors(RLTs)have an extremely low likelihood of forming,and some have been recorded only in isolated cases.The lack of normal clinical symptoms in RLTs makes preoperative diagnosis extremely chal... BACKGROUND Rare liver tumors(RLTs)have an extremely low likelihood of forming,and some have been recorded only in isolated cases.The lack of normal clinical symptoms in RLTs makes preoperative diagnosis extremely challenging,which results in frequent misinterpretation.The present case report helps enhance our ability to recognize and treat uncommon liver tumor disorders.CASE SUMMARY We describe four distinct examples of rare liver tumor diseases.These cases were all true cases with no conventional clinical signs or imaging findings.In all patients,hepatic occupancy was discovered on physical examination,which raised the preoperative suspicion of hepatic cancer.All tumors were surgically removed,and postoperative histology and immunohistochemistry were performed to confirm the diagnosis.The first patient had primary hepatic fibrosarcoma.The second case involved a primary hepatic neuroendocrine tumors.These two patients had malignant liver tumors,and both had extremely satisfactory surgical outcomes.The third case involved focal hepatic steatosis,and the fourth case involved a single necrotic nodule in the liver.These two patients had benign liver tumors,but they had already undergone surgery and did not require any postoperative care.CONCLUSION The number of patients with RLTs is small,and the clinical and imaging results are vague.Preoperative diagnosis is challenging,and patients are sometimes mistakenly diagnosed with liver cancer,which leads to unnecessary surgical therapy in certain individuals. 展开更多
关键词 Liver tumor Primary hepatic fibrosarcoma Primary hepatic neuroendocrine tumor Focal hepatic steatosis Solitary necrotic nodule of the liver Lack of typical clinical symptoms Case report
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Formulation of Work-Study Combined and Result-Oriented Integrated Curriculum Standards
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作者 Lianfang LI Chunhua DU +2 位作者 Fen YANG Yun LI Yanfei NIU 《Medicinal Plant》 2024年第3期79-83,共5页
According to the Annex Technical Regulations for Integrated Curriculum Development(Trial)in Document No.30 of the General Office of the Ministry of Human Resources and Social Security(2012),this paper studies the form... According to the Annex Technical Regulations for Integrated Curriculum Development(Trial)in Document No.30 of the General Office of the Ministry of Human Resources and Social Security(2012),this paper studies the formulation of the curriculum standards for the integration of Chinese medicinal materials production.We focus on the formulation ideas of the curriculum standards for the integration of Chinese medicinal materials production,the formulation process of the curriculum standards for the integration of Chinese medicinal materials production,including the description of typical work tasks,the determination of curriculum objectives,the analysis of study content,the description of referential study tasks,teaching implementation suggestions,assessment and evaluation suggestions,which can provide a reference for the development and research of other related integrated courses. 展开更多
关键词 Integration of WORK and STUDY WORK process Curriculum STANDARDS Production of Chinese MEDICINAL materials Typical WORK TASKS REFERENTIAL STUDY TASKS
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Analysis on Typical Spatio-temporal Characteristics of Open-cast Mining and Its Countermeasures
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作者 Qingyou AO Qiang FU +2 位作者 Zhihua LIU Yu XUN Lin LIN 《Asian Agricultural Research》 2024年第5期20-24,共5页
In order to deal with the special spatio-temporal environmental changes encountered in the process of open-cast mining,taking Huolinhe No.1 Open-cast Mine as the research object,this paper studied its typical problems... In order to deal with the special spatio-temporal environmental changes encountered in the process of open-cast mining,taking Huolinhe No.1 Open-cast Mine as the research object,this paper studied its typical problems in river reconstruction and cultural relics protection.The study focused on eight key core aspects,including the design optimization of the spatial layout of the mining area,the accurate estimation of the mineral resources reserves,the scientific theoretical demonstration of the mining scale,the fine analysis and calculation of the stripping ratio,the comprehensive consideration of the transport distance and efficiency,the accurate judgment of the best time for the implementation of the transformation,the analysis and evaluation of the slope stability,and the overall planning of the production system.The results show that the extracted problem-solving strategies and scheme system for special mining conditions can not only provide specific and practical guidance for Huolinhe No.1 Open-cast Mine,but also serve as a valuable reference and practical reference for other open-cast mine enterprises facing similar challenges. 展开更多
关键词 Open-cast mining in the mining area Typical space-time environment River reconstruction Cultural relics protection Spatial layout
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Steering Towards Progress
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作者 Gao Yuan 《China Report ASEAN》 2024年第8期18-21,共4页
Each Central Committee of the Communist Party of China(CPC)convenes at least one plenary session each year during its five-year term.Among these,the third plenary session attracts the most attention as it typically sh... Each Central Committee of the Communist Party of China(CPC)convenes at least one plenary session each year during its five-year term.Among these,the third plenary session attracts the most attention as it typically shines light on major decisions that embody the governing guidelines of the current central leadership. 展开更多
关键词 typically SESSION COMMUNIST
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Analysis of a Typical Case of Meteorological Service in Tangpu Reservoir
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作者 Quan SHAN Yuxin DING +2 位作者 Tingting GU Jinxin WANG Kai TANG 《Meteorological and Environmental Research》 2024年第2期44-47,共4页
The continuous rainy precipitation process from February to March in 2019 was selected to analyze the effect of meteorological service in Tangpu Reservoir basin,so as to sum up service experience and then lay a better... The continuous rainy precipitation process from February to March in 2019 was selected to analyze the effect of meteorological service in Tangpu Reservoir basin,so as to sum up service experience and then lay a better foundation for subsequent services.In response to the rainy weather from December 2018 to early 2019,three rounds of flood discharge were carried out in Tangpu Reservoir.During February-March in 2019,the hit rate of short-term area rainfall forecast for Tangpu Reservoir was 80.0%.Compared with the median of forecast interval,the average absolute error was 7.6 mm,and the relative error was 32.7%.The large deviation in the forecast from March 27 to 28 was deeply analyzed,and it is found that the main reasons were excessive reliance on and trust in a single model,insufficient correction of the actual situation,and insufficient judgment of the nature of precipitation.For the future reservoir meteorological service,three aspects of thinking were put forward,such as further strengthening the sharing of hydrological and meteorological information,improving the forecasting ability,and deepening the research of runoff forecast models. 展开更多
关键词 Tangpu Reservoir Meteorological service Continuous rain Analysis of a typical case
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Information Conservation in a Noncommutative Quantum Black Hole Based on Canonical Typicality
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作者 Dong-Shan He 《Communications in Theoretical Physics》 SCIE CAS CSCD 2019年第8期1007-1010,共4页
A method for calculating the radiation spectrum of an arbitrary black holes was recently proposed by Ma et al.,[Europhys.Lett.122(2018) 30001] in which a non-thermal spectrum of a black hole can be obtained from its e... A method for calculating the radiation spectrum of an arbitrary black holes was recently proposed by Ma et al.,[Europhys.Lett.122(2018) 30001] in which a non-thermal spectrum of a black hole can be obtained from its entropy using an approach based on canonical typicality.The non-thermal spectrum of a black hole enables a nonzero correlation between the black hole and its radiation, which can ensure that information is conserved during black hole evaporation.In this paper, by using the Kantowski-Sachs metric and Feynman-Hibbs procedure, the entropy of a noncommutative quantum black hole is calculated based on the Wheeler-DeWitt equation.Then, the radiation spectrum of the noncommutative quantum black hole is studied based on canonical typicality method.At last, the correlation between the radiation spectra is calculated.It is shown that the noncommutative effect increases the correlation among radiation and the information remains conserved for noncommutative quantum black holes. 展开更多
关键词 INFORMATION CONSERVATION NONCOMMUTATIVE black hole CANONICAL typicality
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AUnique Brocade Thangka Depicting the ETIQUETTE INTERACTIONS DURING THE MING DYNASTY
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作者 Liu Dongmei Rigzintsho Huang Wenjuan(Translated) 《China's Tibet》 2024年第4期34-39,共6页
The traditional way of Chakrasamvara was typically depicted with a furrowed brow and intensescowl.However,thefigure in this Chakrasamvara Thangka instead features eyebrows resembling gentle waves and eyes that smile.D... The traditional way of Chakrasamvara was typically depicted with a furrowed brow and intensescowl.However,thefigure in this Chakrasamvara Thangka instead features eyebrows resembling gentle waves and eyes that smile.Does this suggest that thedepictions of Buddha can vary significantly,reflecting different cultural interpretations or different"memes"? 展开更多
关键词 GENTLE instead typically
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Trade-off and Synergy of Rural Functions Under County Depopulation in the Typical Black Soil Region of Northeast China 被引量:2
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作者 LI Dongmei WEN Qing +1 位作者 QI Yue ZHANG Pingyu 《Chinese Geographical Science》 SCIE CSCD 2023年第4期616-633,共18页
As the population continues to shrink in the black soil region of Northeast China since 2000,it is critical to master the impact of population shrinkage on rural functions to realize rural revitalization and sustainab... As the population continues to shrink in the black soil region of Northeast China since 2000,it is critical to master the impact of population shrinkage on rural functions to realize rural revitalization and sustainable development.In this study,we focused on the impacts of depopulation on the evolution and interrelationship of rural subfunctions.Based on the rural function indexes system,the TOPSIS(Technique for Order Preference by Similarity to an Ideal Solution)method,spatial analysis method,and mathematical statistics analysis method were used to summarize the spatial and temporal characteristics of rural function development,as well as the effect of population shrinkage in the typical black soil region of Northeast China.The results showed that depopulation varied in the extent and duration between the forested region and plain areas,which both impacted the trajectories of rural subfunctions evolution.For the economic development function and ecological conservation function,the effect of continuous slight depopulation was beneficial,while the effect of rapid depopulation was adverse,which was exactly opposite to the agricultural production function.All forms of population shrinkage were conducive to the development of the social security function.With the deepening population shrinkage,depopulation mainly promoted the collaborative development between subfunctions in this study,except the relationship between agricultural production and social security function.But effects of depopulation on the interrelationship of rural subfunctions varied between the forested region and plain areas in some cases.The results provided evidence for the cognition that population shrinkage had complicated effects on rural subfunctions. 展开更多
关键词 rural function depopulation trade-off and synergy typical black soil region Northeast China
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The Response of Anomalous Vertically Integrated Moisture Flux Patterns Related to Drought and Flood in Southern China to Sea Surface Temperature Anomaly 被引量:3
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作者 董娜 徐祥德 +4 位作者 蔡雯悦 王春竹 赵润泽 魏凤英 孙婵 《Journal of Tropical Meteorology》 SCIE 2023年第2期179-190,共12页
With the extreme drought(flood)event in southern China from July to August in 2022(1999)as the research object,based on the comprehensive diagnosis and composite analysis on the anomalous drought and flood years from ... With the extreme drought(flood)event in southern China from July to August in 2022(1999)as the research object,based on the comprehensive diagnosis and composite analysis on the anomalous drought and flood years from July to August in 1961-2022,it is found that there are significant differences in the characteristics of the vertically integrated moisture flux(VIMF)anomaly circulation pattern and the VIMF convergence(VIMFC)anomaly in southern China in drought and flood years,and the VIMFC,a physical quantity,can be regarded as an indicative physical factor for the"strong signal"of drought and flood in southern China.Specifically,in drought years,the VIMF anomaly in southern China is an anticyclonic circulation pattern and the divergence characteristics of the VIMFC are prominent,while those are opposite in flood years.Based on the SST anomaly in the typical draught year of 2022 in southern China and the SST deviation distribution characteristics of abnormal draught and flood years from 1961 to 2022,five SST high impact areas(i.e.,the North Pacific Ocean,Northwest Pacific Ocean,Southwest Pacific Ocean,Indian Ocean,and East Pacific Ocean)are selected via the correlation analysis of VIMFC and the global SST in the preceding months(May and June)and in the study period(July and August)in 1961-2022,and their contributions to drought and flood in southern China are quantified.Our study reveals not only the persistent anomalous variation of SST in the Pacific and the Indian Ocean but also its impact on the pattern of moisture transport.Furthermore,it can be discovered from the positive and negative phase fitting of SST that the SST composite flow field in high impact areas can exhibit two types of anomalous moisture transport structures that are opposite to each other,namely an anticyclonic(cyclonic)circulation pattern anomaly in southern China and the coastal areas of east China.These two types of opposite anomalous moisture transport structures can not only drive the formation of drought(flood)in southern China but also exert its influence on the persistent development of the extreme weather. 展开更多
关键词 drought in southern China in 2022 VIMFC anomaly high impact areas of SST anomaly anomalous moisture transport circulation pattern typical drought and flood years
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Towards Energy-Efficient Autonomous Driving: A Multi-Objective Reinforcement Learning Approach
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作者 Xiangkun He Chen Lv 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2023年第5期1329-1331,共3页
Dear Editor, With the development of automobile industry and artificial intelligence(AI) domains, autonomous vehicles(AVs) are becoming a reality and promise to revolutionize human mobility [1]–[3]. The decision-maki... Dear Editor, With the development of automobile industry and artificial intelligence(AI) domains, autonomous vehicles(AVs) are becoming a reality and promise to revolutionize human mobility [1]–[3]. The decision-making system of AVs is crucial, which is typically required to trade off multiple competing objectives. For example,when determining driving policies. 展开更多
关键词 typically driving artificial
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A case of atypical neurological symptoms and high cerebro-spinal fluid acetone level due to transdermal exposure to isopropanol
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作者 Côme Fruit Sophie Guillotin +5 位作者 Marie Wolfrum Thomas Lanot Florent Battefort Pierre Girardie Marie Rafiq Nicolas Delcourt 《World Journal of Emergency Medicine》 SCIE CAS CSCD 2023年第2期152-154,共3页
Dear editor, Isopropanol, also named 2-propanol or isopropyl alcohol(IPA), is a colorless, volatile liquid found in numerous household chemicals, such as cleaners and disinfectants, which typically contain a 70% solut... Dear editor, Isopropanol, also named 2-propanol or isopropyl alcohol(IPA), is a colorless, volatile liquid found in numerous household chemicals, such as cleaners and disinfectants, which typically contain a 70% solution of IPA in water. IPA is also extensively used in industry and laboratories as a solvent. 展开更多
关键词 ACETONE typically ALCOHOL
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Changes of spring wind erosion based on wind erosion climate factor in the black soil region of Northeast China
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作者 YAN Ping JI Sheng-tai +5 位作者 LI Xiu-fen ZHU Hai-xia WANG Liang-liang ZHAI Mo WANG Ping ZHAO Hui-ying 《Journal of Mountain Science》 SCIE CSCD 2023年第6期1712-1724,共13页
The dry and windy climate and low ground cover in spring in the black soil region of Northeast China make the soil strongly affected by wind erosion,which seriously threatens the food security and ecological security ... The dry and windy climate and low ground cover in spring in the black soil region of Northeast China make the soil strongly affected by wind erosion,which seriously threatens the food security and ecological security of this region.In this paper,based on the daily observation data of 124 meteorological stations in study area from 1961 to 2020,seasonal and monthly wind erosion climate factor(C)in spring(March to May)were calculated by using the method proposed by the Food and Agriculture Organization of the United Nations(FAO),the wind erosion characterization in spring were systematically analyzed based on C by various statistical analysis methods.The results showed that in the past 60 years,spring wind erosion climate factor(CSp)and monthly C of the whole region and each province(region)all showed highly significant decreasing trend,but they began to show rebounded trend in the middle or late 2000s.CSp of the study area showed a significant upward trend since 2008 with an increase of 4.59(10a)^(-1).The main contributors to this upward trend are the changes of C in March and in April.For the four provinces(regions),CSp in Heilongjiang,Jilin,Liaoning and eastern Inner Mongolia all showed rebounded since 2008,2011,2008 and 2009,respectively.The rebounded trend of CSp in eastern Inner Mongolia was the most obvious with a tendency rate of 11.27(10a)^(-1),and its mutation occurred after 1984.The rebound trend of CSp in Heilongjiang Province takes the second place,with a trend rate of 4.72(10a)^(-1),but there’s no obvious time mutation characteristics.The spatial characteristics of CSpand monthly C are similar,showing decreasing characteristics centered on the typical black soil belt of Northeast China.Compared with 1961-1990,in the period from 1991 to 2020,the proportion of high value areas(CSp>35,monthly C>10)has decreased to varying degrees,while the proportion of low value areas(CSp≤10,monthly C≤4)has increased.The trends of seasonal and monthly C in 82.2%~87.7%of the stations show significant decreases at 95%confidence level.CSp is closely related to wind speed at 2m height,temperature difference,minimum temperature and precipitation in the same period,of which the correlation between CSp and wind speed is the strongest,indicating that the main control factor for CSp in the study area is wind speed,but the impact of the change of temperature and precipitation on CSp cannot be ignored. 展开更多
关键词 Wind erosion climate erosivity Spatiotemporal 1characteristics Climate change Rebounded trend Typical black soil region Northeast China
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Characteristics of sub-synchronous oscillation in grid-connected wind farm system
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作者 Yan Gong Qi Huang +1 位作者 Dong-Sheng Cai Bamisile Olusola Olorunfemi 《Journal of Electronic Science and Technology》 EI CSCD 2023年第4期91-101,共11页
With the rapid development of wind power, wind turbines are accompanied by a large quantity of power electronic converters connected to the grid, causing changes in the characteristics of the power system and leading ... With the rapid development of wind power, wind turbines are accompanied by a large quantity of power electronic converters connected to the grid, causing changes in the characteristics of the power system and leading to increasingly serious sub-synchronous oscillation (SSO) problems, which urgently require the generalized classification and characterization of the emerging oscillation problems. This paper classifies and characterizes the emerging types of SSO caused by grid-connected wind turbines to address these issues. Finally, the impact of the typical system parameters changes on the oscillation pattern is analyzed in depth to provide effective support for the subsequent suppression and prevention of SSO. 展开更多
关键词 CHARACTERISTICS CLASSIFICATION Sub-synchronous oscillation(SSO) Typical system parameters Wind farm
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