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Qualitative analysis for state/event fault trees using formal model checking 被引量:3
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作者 JIANG Quan ZHU Chunling WANG Siqi 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2019年第5期959-973,共15页
A state/event fault tree(SEFT)is a modeling technique for describing the causal chains of events leading to failure in software-controlled complex systems.Such systems are ubiquitous in all areas of everyday life,and ... A state/event fault tree(SEFT)is a modeling technique for describing the causal chains of events leading to failure in software-controlled complex systems.Such systems are ubiquitous in all areas of everyday life,and safety and reliability analyses are increasingly required for these systems.SEFTs combine elements from the traditional fault tree with elements from state-based techniques.In the context of the real-time safety-critical systems,SEFTs do not describe the time properties and important timedependent system behaviors that can lead to system failures.Further,SEFTs lack the precise semantics required for formally modeling time behaviors.In this paper,we present a qualitative analysis method for SEFTs based on transformation from SEFT to timed automata(TA),and use the model checker UPPAAL to verify system requirements’properties.The combination of SEFT and TA is an important step towards an integrated design and verification process for real-time safety-critical systems.Finally,we present a case study of a powerboat autopilot system to confirm our method is viable and valid after achieving the verification goal step by step. 展开更多
关键词 state/event fault tree (SEFT) TIMED AUTOMATA (TA) model transformation safety analysis
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To Change or Not to Change: A Case Study of “V + Dào” Construction as the State Change Event from the Perspective of the Event Integration Hypothesis
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作者 Lin Yu 《Open Journal of Applied Sciences》 2025年第1期329-351,共23页
This study examines the “V + Dào” construction as a state change event through the lens of the Event Integration Hypothesis. It focuses on how these constructions represent state changes, exploring distinctions... This study examines the “V + Dào” construction as a state change event through the lens of the Event Integration Hypothesis. It focuses on how these constructions represent state changes, exploring distinctions between “change” and “stasis”. Using a corpus-based approach, the analysis covers the semantic and syntactic features of “V + Dào” constructions and their event integration patterns. The findings highlight the distribution of agency, animacy, and support relations in state change events, emphasizing the complex interaction of internal and external event integrations and their correlation with the conceptual primitives of change and transition. This study offers insights into the lexicalization and grammaticalization processes of the “V + Dào” construction, and potentially the broader verb-complement constructions in Mandarin. 展开更多
关键词 “V + Dào” Construction state Change event event Integration Semantic Properties Syntactic Properties
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Safety profile of artemether:Analysis based on 15-year data retrived from FDA adverse event reporting system(FAERS)
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作者 Bo Jiang Jiaxin Wei +3 位作者 Xiaochen Liu Longlin He Taotao Hou Bin Niu 《Asian Pacific Journal of Tropical Medicine》 2026年第1期33-44,共12页
Objective:Artemether is a semi-synthetic derivative of artemisinin and is widely used in the treatment of Plasmodium(P.)falciparum malaria.This study aimed to characterize the safety profile of artemether based on 15-... Objective:Artemether is a semi-synthetic derivative of artemisinin and is widely used in the treatment of Plasmodium(P.)falciparum malaria.This study aimed to characterize the safety profile of artemether based on 15-year data retrived from FDA adverse event reporting system(FAERS).Methods:This is a retrospective analysis on 15-year data of artemether-related adverse effects(AEs)retrieved from the FAERS.AEs were classified according to System Organ Class(SOC)and Preferred Terms(PT).Signal detection was performed using Reporting Odds Ratios(ROR),Proportional Reporting Ratios(PRR),and Empirical Bayes Geometric Mean(EBGM).Stratified analyses examined the impact of demographic factors such as sex,age,and time-to-onset.Temporal patterns and associated risk factors were also investigated.Results:Haemolytic anaemia and haemolysis emerged as the most frequently reported AEs,exhibiting significantly elevated RORs(males:ROR 381.36,95%CI 247.06-588.60;females:ROR 455.11,95%CI 286.43-723.12).Sex-specific differences were evident,with females showing a higher incidence of reproductive-related AEs,including spontaneous abortion and premature labour.Temporal trend analysis revealed that the majority of AEs occurred within the first 30 days after the initiation of artemether administration,indicating a rapid onset.The most affected SOCs were blood and lymphatic system disorders and hepatobiliary disorders.Conclusions:Artemether is associated with a notable frequency of early-onset AEs,particularly hematological and hepatobiliary disorders.The observed sex-specific vulnerability to reproductive AEs highlights the need for sex-conscious clinical approaches.Enhanced post-treatment monitoring and further investigations into the drug’s pharmacokinetics and mechanistic pathways are recommended. 展开更多
关键词 ARTEMETHER Adverse events FDA adverse event reporting system Signal detection Hematological toxicity HEPATOTOXICITY
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Random State Approach to Quantum Computation of Electronic-Structure Properties
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作者 Yiran Bai Feng Xiong Xueheng Kuang 《Chinese Physics Letters》 2026年第1期89-104,共16页
Classical computation of electronic properties in large-scale materials remains challenging.Quantum computation has the potential to offer advantages in memory footprint and computational scaling.However,general and v... Classical computation of electronic properties in large-scale materials remains challenging.Quantum computation has the potential to offer advantages in memory footprint and computational scaling.However,general and viable quantum algorithms for simulating large-scale materials are still limited.We propose and implement random-state quantum algorithms to calculate electronic-structure properties of real materials.Using a random state circuit on a small number of qubits,we employ real-time evolution with first-order Trotter decomposition and Hadamard test to obtain electronic density of states,and we develop a modified quantum phase estimation algorithm to calculate real-space local density of states via direct quantum measurements.Furthermore,we validate these algorithms by numerically computing the density of states and spatial distributions of electronic states in graphene,twisted bilayer graphene quasicrystals,and fractal lattices,covering system sizes from hundreds to thousands of atoms.Our results manifest that the random-state quantum algorithms provide a general and qubit-efficient route to scalable simulations of electronic properties in large-scale periodic and aperiodic materials. 展开更多
关键词 periodic materials random state circuit random state quantum algorithms electronic structure properties density states aperiodic materials quantum algorithms quantum computation
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Spatial pattern of hourly precipitation events in China revealed by precipitation event detection indices
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作者 ZHANG Yihui LIANG Kang LIU Changming 《Journal of Geographical Sciences》 2026年第1期129-148,共20页
Precipitation events,which follow a life cycle of initiation,development,and decay,represent the fundamental form of precipitation.Comprehensive and accurate detection of these events is crucial for effective water re... Precipitation events,which follow a life cycle of initiation,development,and decay,represent the fundamental form of precipitation.Comprehensive and accurate detection of these events is crucial for effective water resource management and flood control.However,current investigations on their spatio-temporal patterns remain limited,largely because of the lack of systematic detection indices that are specifically designed for precipitation events,which constrains event-scale research.In this study,we defined a set of precipitation event detection indices(PEDI)that consists of five conventional and fourteen extreme indices to characterize precipitation events from the perspectives of intensity,duration,and frequency.Applications of the PEDI revealed the spatial patterns of hourly precipitation events in China and its first-and second-order river basins from 2008 to 2017.Both conventional and extreme precipitation events displayed spatial distribution patterns that gradually decreased in intensity,duration,and frequency from southeast to northwest China.Compared with those in northwest China,the average values of most PEDIs in southeast China were usually 2-10 times greater for first-order river basins and 3-15 times greater for second-order basins.The PEDI could serve as a reference method for investigating precipitation events at global,regional,and basin scales. 展开更多
关键词 precipitation events precipitation event detection indices(PEDI) spatial heterogeneity IETD(inter-event time definition)method
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Topological Corner States due to Boundary Defects
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作者 Yiqi Zhang Yuwei Hu +1 位作者 Yongdong Li Ce Shang 《Chinese Physics Letters》 2026年第1期44-48,共5页
In conventional higher-order topological insulators(HOTIs),the emergence of topological states can be explained by using the nonzero bulk polarization index.However,corner states emerge in HOTIs with incomplete bounda... In conventional higher-order topological insulators(HOTIs),the emergence of topological states can be explained by using the nonzero bulk polarization index.However,corner states emerge in HOTIs with incomplete boundary unit cells(i.e.,boundary defects)even though the bulk polarization is zero,which challenges the conventional understanding of HOTIs.Here,based on a Kekul´e-distorted honeycomb lattice with incomplete unit cells,we reveal that incomplete unit cells exhibit fractional charges through the analysis of Wannier centers by developing a compensation method and creating the concept of Wannier center domain(WCD)which is the smallest region that one Wannier center occupies.This method compensates for the missing parts of these boundary incomplete unit cells with additional WCDs to make them complete.The compensated WCDs automatically carry the corresponding charge,and this charge together with that of the incomplete unit cell constitutes the total charge of the complete unit cell after compensation.We conclude that the emergence of corner states is attributed to the filling anomaly,which is a fundamental mechanism.Our results refresh the understanding of HOTIs,especially those with structural discontinuities,and provide a novel design for topological states which have application value in producing optical functional devices. 展开更多
关键词 unit cellswe higher order topological insulators topological corner states boundary unit cells ieboundary incomplete unit cells bulk polarization index fractional charges emergence topological states
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Enhanced semi-supervised learning for top gas flow state classification to optimize emission and production in blast ironmaking furnaces
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作者 Song Liu Qiqi Li +3 位作者 Qing Ye Zhiwei Zhao Dianyu E Shibo Kuang 《International Journal of Minerals,Metallurgy and Materials》 2026年第1期204-216,共13页
Automated classification of gas flow states in blast furnaces using top-camera imagery typically demands a large volume of labeled data,whose manual annotation is both labor-intensive and cost-prohibitive.To mitigate ... Automated classification of gas flow states in blast furnaces using top-camera imagery typically demands a large volume of labeled data,whose manual annotation is both labor-intensive and cost-prohibitive.To mitigate this challenge,we present an enhanced semi-supervised learning approach based on the Mean Teacher framework,incorporating a novel feature loss module to maximize classification performance with limited labeled samples.The model studies show that the proposed model surpasses both the baseline Mean Teacher model and fully supervised method in accuracy.Specifically,for datasets with 20%,30%,and 40%label ratios,using a single training iteration,the model yields accuracies of 78.61%,82.21%,and 85.2%,respectively,while multiple-cycle training iterations achieves 82.09%,81.97%,and 81.59%,respectively.Furthermore,scenario-specific training schemes are introduced to support diverse deployment need.These findings highlight the potential of the proposed technique in minimizing labeling requirements and advancing intelligent blast furnace diagnostics. 展开更多
关键词 blast furnace gas flow state semi-supervised learning mean teacher feature loss
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Emotion regulation habits and emotional states of college students during lockdown:A cross-sectional survey
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作者 Shu-Xin Zhao Tao Han +7 位作者 Wei-Zhi Bi Le-Le Fei Lu-Luan Han Yu-Lin Wang Zhi-Guang Ping Chong-Jian Wang Chang-Fu Hao Yong-Juan Xin 《World Journal of Psychiatry》 2026年第1期244-255,共12页
BACKGROUND The prevalence of negative emotional states,such as anxiety and depression,has increased annually.Although personal habits are known to influence emotional regulation,the precise mechanisms underlying this ... BACKGROUND The prevalence of negative emotional states,such as anxiety and depression,has increased annually.Although personal habits are known to influence emotional regulation,the precise mechanisms underlying this relationship remain unclear.AIM To investigate emotion regulation habits impact on students negative emotions during lockdown,using the coronavirus disease 2019 pandemic as a case example.METHODS During the coronavirus disease 2019 lockdown,an online cross-sectional survey was conducted at a Chinese university.Emotional states were assessed using the Depression,Anxiety,and Stress Scale-21(DASS-21),while demographic data and emotion regulation habits were collected concurrently.Data analysis was performed using SPSS version 27.0 and includedχ^(2)-tests for intergroup comparisons,Spearman’s rank-order correlation coefficient analysis to examine associations,and stepwise linear regression modeling to explore the relationships between emotion regulation habits and emotional states.Statistical significance was set atα=0.05.RESULTS Among the 494 valid questionnaires analyzed,the prevalence rates of negative emotional states were as follows:Depression(65.0%),anxiety(69.4%),and stress(50.8%).DASS-21 scores(mean±SD)demonstrated significant symptomatology:Total(48.77±34.88),depression(16.21±12.18),anxiety(14.90±11.91),and stress(17.64±12.07).Significant positive intercorrelations were observed among all DASS-21 subscales(P<0.01).Regression analysis identified key predictors of negative emotions(P<0.05):Risk factors included late-night frequency and academic pressure,while protective factors were the frequency of parental contact and the number of same-gender friends.Additionally,compensatory spending and binge eating positively predicted all negative emotion scores(β>0,P<0.01),whereas appropriate recreational activities negatively predicted these scores(β<0,P<0.01).CONCLUSION High negative emotion prevalence occurred among confined students.Recreational activities were protective,while compensatory spending and binge eating were risk factors,necessitating guided emotion regulation. 展开更多
关键词 Emotional states Emotion regulation habits College students Coronavirus disease 2019 Lockdown PREVALENCE
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Deep Learning-Enhanced Human Sensing with Channel State Information: A Survey
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作者 Binglei Yue Aili Jiang +3 位作者 Chun Yang Junwei Lei Heng Liu Yin Zhang 《Computers, Materials & Continua》 2026年第1期1-28,共28页
With the growing advancement of wireless communication technologies,WiFi-based human sensing has gained increasing attention as a non-intrusive and device-free solution.Among the available signal types,Channel State I... With the growing advancement of wireless communication technologies,WiFi-based human sensing has gained increasing attention as a non-intrusive and device-free solution.Among the available signal types,Channel State Information(CSI)offers fine-grained temporal,frequency,and spatial insights into multipath propagation,making it a crucial data source for human-centric sensing.Recently,the integration of deep learning has significantly improved the robustness and automation of feature extraction from CSI in complex environments.This paper provides a comprehensive review of deep learning-enhanced human sensing based on CSI.We first outline mainstream CSI acquisition tools and their hardware specifications,then provide a detailed discussion of preprocessing methods such as denoising,time–frequency transformation,data segmentation,and augmentation.Subsequently,we categorize deep learning approaches according to sensing tasks—namely detection,localization,and recognition—and highlight representative models across application scenarios.Finally,we examine key challenges including domain generalization,multi-user interference,and limited data availability,and we propose future research directions involving lightweight model deployment,multimodal data fusion,and semantic-level sensing. 展开更多
关键词 Channel state Information(CSI) human sensing human activity recognition deep learning
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Coexistence of near-E_(F) Van Hove Singularity and in-Gap Topological Dirac Surface States in Superconducting Electrides
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作者 Yin Yang Peihan Sun +9 位作者 Ye Shen Zhijun Tu Pengcheng Ma Hongrun Zhen Tianqi Wang Longli Tian Tian Cui Hechang Lei Kai Liu Zhonghao Liu 《Chinese Physics Letters》 2026年第1期213-217,共5页
Superconducting elect rides have attracted growing attention for their potential to achieve high superconducting transition temperatures(T_(C))under pressure.However,many known elect rides are chemically reactive and ... Superconducting elect rides have attracted growing attention for their potential to achieve high superconducting transition temperatures(T_(C))under pressure.However,many known elect rides are chemically reactive and unstable,making high-quality single-crystal growth,characterization,and measurements difficult,and most do not exhibit superconductivity at ambient pressure.In contrast,La_(3) In stands out for its ambient-pressure superconductivity(T_(C)∼9.4 K)and the availability of high-quality single crystals.Here,we investigate its low-energy electronic structure using angle-resolved photoemission spectroscopy and first-principles calculations.The bands near the Fermi energy(E_(F))are mainly derived from La 5d and In 5p orbitals.A saddle point is directly observed at the Brillouin zone(BZ)boundary,while a three-dimensional Van Hove singularity crosses E_(F) at the BZ corner.First-principles calculations further reveal topological Dirac surface states within the bulk energy gap above E_(F).The coexistence of a high density of states and in-gap topological surface states near𝐸F suggests that La3In offers a promising platform for tuning superconductivity and exploring possible topological superconducting phases through doping or external pressure. 展开更多
关键词 ambient pressure superconductivity superconducting elect rides gap topological Dirac surface states La superconducting electrides near e f Van Hove singularity angle resolved photoemission spectroscopy elect rides
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Hybridization Gap and Edge States in Strained-Layer InAs/In_(0.5)Ga_(0.5)Sb Quantum Spin Hall Insulator
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作者 Wenfeng Zhang Peizhe Jia +4 位作者 Wen-kai Lou Xinghao Wang Shaokui Su Kai Chang Rui-Rui Du 《Chinese Physics Letters》 2026年第1期179-183,共5页
The hybridization gap in strained-layer InAs/In_(x)Ga_(1−x) Sb quantum spin Hall insulators(QSHIs)is significantly enhanced compared to binary InAs/GaSb QSHI structures,where the typical indium composition,x,ranges be... The hybridization gap in strained-layer InAs/In_(x)Ga_(1−x) Sb quantum spin Hall insulators(QSHIs)is significantly enhanced compared to binary InAs/GaSb QSHI structures,where the typical indium composition,x,ranges between 0.2 and 0.4.This enhancement prompts a critical question:to what extent can quantum wells(QWs)be strained while still preserving the fundamental QSHI phase?In this study,we demonstrate the controlled molecular beam epitaxial growth of highly strained-layer QWs with an indium composition of x=0.5.These structures possess a substantial compressive strain within the In_(0.5)Ga_(0.5)Sb QW.Detailed crystal structure analyses confirm the exceptional quality of the resulting epitaxial films,indicating coherent lattice structures and the absence of visible dislocations.Transport measurements further reveal that the QSHI phase in InAs/In_(0.5)Ga_(0.5)Sb QWs is robust and protected by time-reversal symmetry.Notably,the edge states in these systems exhibit giant magnetoresistance when subjected to a modest perpendicular magnetic field.This behavior is in agreement with the𝑍2 topological property predicted by the Bernevig–Hughes–Zhang model,confirming the preservation of topologically protected edge transport in the presence of enhanced bulk strain. 展开更多
关键词 strained layer quantum spin hall insulators qshis InAs Ga Sb edge states quantum wells qws be controlled molecular beam epitaxial growth hybridization gap quantum spin Hall insulator
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A-site doping enabled synergistic regulation of phase transition and electron spin state for improved performance of La_(0.6)Ca_(0.4)FeO_(3-δ)cathodes in solid oxide fuel cells
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作者 Na Lv Yumei Ma +1 位作者 Lina Su Ling Huang 《Nano Research》 2026年第1期589-597,共9页
Although intermediate temperature solid oxide fuel cells(IT-SOFCs)show great potential to address energy conversion challenges,the sluggish oxygen reduction reaction(ORR)kinetics of cathode materials has severely hind... Although intermediate temperature solid oxide fuel cells(IT-SOFCs)show great potential to address energy conversion challenges,the sluggish oxygen reduction reaction(ORR)kinetics of cathode materials has severely hindered extended applications.Herein,we have demonstrated that Bi^(3+)doping on the A-site synergistically regulates the phase transition and electron spin state in La_(0.3)Bi_(0.3)Ca_(0.4)FeO_(3-δ)(LBCF3)for improved performance.An orthorhombic to cubic phase transition occurred with Bi^(3+)doping increases oxygen vacancy concentration and thus increases oxygen ion migration capacity.Simultaneously,the change of Fe from low to medium electron spin state strengths O_(2)adsorption and improves catalytic performances.Consequently,a peak power density improvement up to 48%(from 1.21 to 1.79 W·cm^(-2))at 800℃ is realized in the anodesupported single cell using LBCF3 as cathode,which remains stable for over 270 h at 750℃. 展开更多
关键词 solid oxide fuel cells La_(0.6)Ca_(0.4)FeO_(3-δ) A-site modulation spin state transition oxygen reduction reaction(ORR)
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基于Event模型的城市物流无人机同高度交叉运行间隔研究
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作者 张健 赵嶷飞 +2 位作者 卢飞 黎宗孝 罗鑫悦 《中国安全科学学报》 北大核心 2025年第5期99-105,共7页
为解决城市物流无人机飞行流量加大、隔离航线模式空域利用率低的矛盾,需要实施安全有效的交叉运行。通过研究交叉运行碰撞风险,确定侧向误差、垂直误差、纵向临近率等核心参数,构建同高度交叉运行间隔模型。在此基础上,进一步考虑机载... 为解决城市物流无人机飞行流量加大、隔离航线模式空域利用率低的矛盾,需要实施安全有效的交叉运行。通过研究交叉运行碰撞风险,确定侧向误差、垂直误差、纵向临近率等核心参数,构建同高度交叉运行间隔模型。在此基础上,进一步考虑机载冲突探测与解脱(CDR)系统失效问题,并运用事件树分析方法,提出并构建城市物流无人机交叉间隔综合模型。结果表明:在航线夹角为60°情况下,对标安全目标水平1.5×10^(-8),所需交叉间隔为158 m;对标安全目标水平1×10^(-6),所需交叉间隔155 m。随着交叉角度增大,运行间隔总体呈现上升趋势,当接近180°时,即对头运行时,所需间隔急剧上升,与实际认知一致。 展开更多
关键词 event模型 城市物流无人机(UAV) 同高度 交叉运行 交叉间隔 冲突探测与解脱(CDR)
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Characteristics of the spatiotemporal distribution of daily extreme temperature events in China:Minimum temperature records in different climate states against the background of the most probable temperature 被引量:2
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作者 钱忠华 胡经国 +1 位作者 封国林 曹永忠 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第10期614-621,共8页
Based on the skewed function,the most probable temperature is defined and the spatiotemporal distributions of the frequencies and strengths of extreme temperature events in different climate states over China are inve... Based on the skewed function,the most probable temperature is defined and the spatiotemporal distributions of the frequencies and strengths of extreme temperature events in different climate states over China are investigated,where the climate states are referred to as State I,State II and State III,i.e.,the daily minimum temperature records of 1961-1990,1971-2000,and 1981-2009.The results show that in space the frequency of high temperature events in summer decreases clearly in the lower and middle reaches of the Yellow River in State I and that low temperature events decrease in northern China in State II.In the present state,the frequency of high temperature events increases significantly in most areas over China except the north east,while the frequency of low temperature events decreases mainly in north China and the regions between the Yangtze River and the Yellow River.The distributions of frequencies and strengths of extreme temperature events are consistent in space.The analysis of time evolution of extreme events shows that the occurrence of high temperature events become higher with the change in state,while that of low temperature events decreases.High temperature events are becoming stronger as well and deserve to be paid special attention. 展开更多
关键词 extreme temperature most probable temperature climate state
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Multitarget stool DNA for colorectal cancer screening:A review and commentary on the United States Preventive Services Draft Guidelines 被引量:4
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作者 Barry M Berger Bernard Levin Robert J Hilsden 《World Journal of Gastrointestinal Oncology》 SCIE CAS 2016年第5期450-458,共9页
Multitarget stool DNA(mt-sDNA) testing was approved for average risk colorectal cancer(CRC) screening by the United States Food and Drug Administration and thereafter reimbursed for use by the Medicare program(2014).T... Multitarget stool DNA(mt-sDNA) testing was approved for average risk colorectal cancer(CRC) screening by the United States Food and Drug Administration and thereafter reimbursed for use by the Medicare program(2014).The United States Preventive Services Task Force(USPSTF) October 2015 draft recommendation for CRC screening included mt-s DNA as an "alternative" screening test that "may be useful in select clinical circumstances",despite its very high sensitivity for early stage CRC.The evidence supporting mt-s DNA for routine screening use is robust.The clinical efficacy of mt-s DNA as measured by sensitivity,specificity,life-years gained(LYG),and CRC deaths averted is similar to or exceeds that of the other more specifically recommended screening options included in the draft document,especially those requiring annual testing adherence.In a population with primarily irregular screening participation,tests with the highest point sensitivity and reasonable specificity are more likely to favorably impact CRC related morbidity and mortality than those depending on annual adherence.This paper reviews the evidence supporting mt-s DNA for routine screening and demonstrates,using USPSTF's modeling data,that mt-s DNA at three-year intervals provides significant clinical net benefits and fewer complications per LYG than annual fecal immunochemical testing,high sensitivity guaiac based fecal occult blood testing and 10-year colonoscopy screening. 展开更多
关键词 Colorectal CANCER screening Multitarget STOOL DNA STOOL DNA The United states Preventive Services Task Force CANCER Intervention Surveillance MODELING Network FECAL immunological technique MODELING Interval
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Event-triggered state estimation for T-S fuzzy affine systems based on piecewise Lyapunov-Krasovskii functionals 被引量:1
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作者 Meng WANG Jianbin QIU Gang FENG 《Control Theory and Technology》 EI CSCD 2019年第1期99-111,共13页
This paper investigates the problem of event-triggered H∞state estimation for Takagi-Sugeno (T-S) fuzzy affine systems. The objective is to design an event-triggered scheme and an observer such that the resulting est... This paper investigates the problem of event-triggered H∞state estimation for Takagi-Sugeno (T-S) fuzzy affine systems. The objective is to design an event-triggered scheme and an observer such that the resulting estimation error system is asymptotically stable with a prescribed H∞performance and at the same time unnecessary output measurement transmission can be reduced. First, an event-triggered scheme is proposed to determine whether the sampled measurements should be transmitted or not. The output measurements, which trigger the condition, are supposed to suffer a network-induced time-varying and bounded delay before arriving at the observer. Then, by adopting the input delay method, the estimation error system can be reformulated as a piecewise delay system. Based on the piecewise Lyapunov-Krasovskii functional and the Finsler's lemma, the event-triggered H∞observer design method is developed. Moreover, an algorithm is proposed to co-design the observer gains and the event-triggering parameters to guarantee that the estimation error system is asymptotically stable with a given disturbance attenuation level and the signal transmission rate is reduced as much as possible. Simulation studies are given to show the effectiveness of the proposed method. 展开更多
关键词 TAKAGI-SUGENO (T-S) FUZZY AFFINE systems event-triggered scheme PIECEWISE LYAPUNOV-KRASOVSKII functional state estimation
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Prothrombotic state and thrombotic events in COVID-19 pandemic period,including portal vein and splenic artery thromboses
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作者 Ozgur Karcioglu Canan Akman Göksu Afacan Ozturk 《World Journal of Clinical Cases》 SCIE 2024年第33期6595-6603,共9页
This editorial article is intended to perform a discussion on the manuscript entitled“Simultaneous portal vein thrombosis and splenic vein thrombosis in a COVID-19 patient:A case report and review of literature”writ... This editorial article is intended to perform a discussion on the manuscript entitled“Simultaneous portal vein thrombosis and splenic vein thrombosis in a COVID-19 patient:A case report and review of literature”written by Abramowitz et al.The article focuses on the diagnostic processes in a 77-year-old-male patient with a simultaneous portal vein and splenic artery thrombosis accompanying coronavirus disease 2019(COVID-19).The authors postulated that splanchnic thrombosis should be on the list of differential diagnoses in a patient presenting with abdominal pain in presence of a COVID-19 infection.The tendency for venous and arterial thrombosis in COVID-19 patients is encountered,largely attributed to hypercoagulopathy.In general,venous thromboembolism mostly manifest as deep vein thrombosis(DVT),pulmonary embolism(PE)or catheterrelated thromboembolic events.Acute PE,DVT,cerebrovascular events and myocardial infarction are seen as the most common thromboembolic complications in COVID-19 patients.COVID-19-associated hemostatic abnormalities include mild thrombocytopenia and increased D-dimer level.Similar to other coagulopathies,the treatment of the underlying condition is the mainstay.Addition of antiplatelet agents can be considered in critically ill patients at low bleeding risk,not on therapeutic anticoagulation,and receiving gastric acid suppression Early administration of antithrombotic drugs will have a beneficial effect in both the prevention and treatment of thrombotic events,especially in non-ambulatory patients.Low molecular weight heparin(LMWH)should be started if there is no contraindication,including in non-critical patients who are at risk of hospitalization LMWH(enoxaparin)is preferred to standard heparin. 展开更多
关键词 Prothrombotic state Thrombotic events COVID-19 PANDEMIC THROMBOEMBOLISM
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Risk of cardiovascular thrombotic events after surgical castration versus gonadotropin-releasing hormone agonists in Chinese men with prostate cancer
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作者 Jeremy YC Teoh Samson YS Chan +4 位作者 Peter KF Chiu Darren MC Poon Ho-Yuen Cheung Simon SM Hou Chi-Fai Ng 《Asian Journal of Andrology》 SCIE CAS CSCD 2015年第3期493-496,共4页
We investigated the cardiovascular thrombotic risk after surgical castration (SC) versus genadotmpin-releasing hormone agonists (GnRHa) in Chinese men with prostate cancer. All Chinese prostate cancer patients who... We investigated the cardiovascular thrombotic risk after surgical castration (SC) versus genadotmpin-releasing hormone agonists (GnRHa) in Chinese men with prostate cancer. All Chinese prostate cancer patients who were treated with SC or GnRHa from year 2000 to 2009 were reviewed and compared. The primary outcome was any new-onset of cardiovascular thrombotic events after SC or GnRHa, which was defined as any event of acute myocardial infarction or ischemic stroke. The risk of new-onset cardiovascular thrombotic event was compared between the SC group and the GnRHa group using Kaplan-Meier method. Multivariate Cox regression analysis was performed to adjust for other potential confounding factors. A total of 684 Chinese patients was included in our study, including 387 patients in the SC group and 297 patients in the GnRHa group. The mean age in the SC group (75.3 ~ 7.5 years) was significantly higher than the GnRHa group (71.8 ~ 8.3 years) (P 〈 0.001). There was increased risk of new cardiovascular thrombotic events in the SC group when compared to the GnRHa group upon Kaplan-Meier analysis (P= 0.014). Upon multivariate Cox regression analysis, age (hazard ratio [HR] 1.072, 95% confidence interval [CI] 1.04-1.11, P 〈 0.001), hyperlipidemia (HR 2.455, 95% Cl 1.53-3.93, P 〈 0.001), and SC (HR 1.648, 95% CI 1.05-2.59, P = 0.031) were significant risk factors of cardiovascular thrombotic events. In conclusion, SC was associated with increased risk of cardiovascular thrombotic events when compared to GnRHa. This is an important aspect to consider while deciding on the method of androgen deprivation therapy, especially in elderly men with known history of hyperlipidemia. 展开更多
关键词 androgen deprivation therapy Chinese population cardiovascular events myocardial infarction prostate cancer STROKE
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Event-triggered model-free adaptive control for a class of surface vessels with time-delay and external disturbance via state observer 被引量:1
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作者 CHEN Hua SHEN Chao +1 位作者 HUANG Jiahui CAO Yuhan 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2023年第3期783-797,共15页
This paper provides an improved model-free adaptive control(IMFAC)strategy for solving the surface vessel trajectory tracking issue with time delay and restricted disturbance.Firstly,the original nonlinear time-delay ... This paper provides an improved model-free adaptive control(IMFAC)strategy for solving the surface vessel trajectory tracking issue with time delay and restricted disturbance.Firstly,the original nonlinear time-delay system is transformed into a structure consisting of an unknown residual term and a parameter term with control inputs using a local compact form dynamic linearization(local-CFDL).To take advantage of the resulting structure,use a discrete-time extended state observer(DESO)to estimate the unknown residual factor.Then,according to the study,the inclusion of a time delay has no effect on the linearization structure,and an improved control approach is provided,in which DESO is used to adjust for uncertainties.Furthermore,a DESO-based event-triggered model-free adaptive control(ET-DESO-MFAC)is established by designing event-triggered conditions to assure Lyapunov stability.Only when the system’s indicator fulfills the provided event-triggered condition will the control input signal be updated;otherwise,the control input will stay the same as it is at the last trigger moment.A coordinate compensation approach is developed to reduce the steady-state inaccuracy of trajectory tracking.Finally,simulation experiments are used to assess the effectiveness of the proposed technique for trajectory tracking. 展开更多
关键词 surface vessels event-triggered condition(ETC) discrete-time extended state observer(DESO) model-free adaptive control(MFAC) coordinate compensation
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Analysis of Data on Adverse Drug Events Reported to the Food and Drugs Administration of the United States of America
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作者 Emmanuel M. Baah 《Open Journal of Statistics》 2020年第2期203-227,共25页
Background: The Spontaneous Reporting System (SRS) of the Food and Drugs Administration (FDA) of the United States of America (US), known as the FDA Adverse Event Reporting System (FAERS), is a mechanism for collectin... Background: The Spontaneous Reporting System (SRS) of the Food and Drugs Administration (FDA) of the United States of America (US), known as the FDA Adverse Event Reporting System (FAERS), is a mechanism for collecting information on safety concerns associated with the use of drugs for redress, as they are used on large scale. The data which is the subject of this paper came from the FAERS database. This paper reports on the analysis of data covering 2013 to 2018 period, but compares the observed trends in the variables during this period with that of the 2007 to 2012 period to ascertain whether the trends change over time;as this paper is, in a sense, a sequel to an earlier one with a similar title as this but covering the period 2007 to 2012. Objectives: The objectives of the study reported in this paper were to: i) explore the trends in the variables involved with the adverse events problem in the 2013 to 2018 period and compare these trends with that found in the study covering the 2007 to 2012 period;ii) determine whether or not the level of missing variable values in the 2013 to 2018 period is lower than, the same or higher than it was in the 2007 to 2012 period;iii) find out how the first twenty principal suspect drugs most cited to be involved in adverse events occurring during drug use in the 2013 to 2018 period compare with that of the 2007 to 2012 period. Methods: The Food and Drugs Administration (FDA) makes extracts from the FAERS database freely available to the public on quarterly basis. Fourteen (14) out of over fifty (50) variables contained in these extracts were reckoned to be connected with the objectives of the study and were examined using the tools of frequencies, proportions and averages, on account of the nature of the data. Results: For the period 2013 to 2018, adverse events reports submitted to the FDA (US) more than doubled (2.1 times), accounting for an annual average growth rate of 15.8 %, which is considerably lower than the annual average growth rate of 22.1% for the 2007 to 2012 period. However, the reported number of cases for 2015 was 53.8% more than that of 2014. Consistent with the results for 2007 to 2012 period, the 2013 to 2018 period saw Female subjects accounting for over 60% of the annual and the overall number of reports. Overall, non-health professionals appear to have a slight edge over health professionals in reporting adverse drug events in the 2013 to 2018 period, with an indication that reports from non-health professionals are on the decline and that from health professionals is on the rise. Non-health professionals and health professionals were almost equally likely to report adverse events in the 2007 to 2012 period. Also, the findings for the 2013 to 2018 period suggest that the older one gets the more vulnerable one becomes to adverse events associated with drug use, which is consistent with the findings for the 2007 to 2012 period. Conclusion: The dangers that come with the use of drugs is an evolving one and therefore there is the need to examine SRS data from time to time so that emerging drug safety concerns can be dealt with timeously. 展开更多
关键词 Drugs ADVERSE DRUG events (ADEs) ADVERSE DRUG Reactions (ADRs) SPONTANEOUS REPORTING System (SRS)
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