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Gas monitoring data anomaly identification based on spatio-temporal correlativity analysis 被引量:3
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作者 Shi-song ZHU Yun-jia WANG Lian-jiang WEI 《Journal of Coal Science & Engineering(China)》 2013年第1期8-13,共6页
Based on spatio-temporal correlativity analysis method, the automatic identification techniques for data anomaly monitoring of coal mining working face gas are presented. The asynchronous correlative characteristics o... Based on spatio-temporal correlativity analysis method, the automatic identification techniques for data anomaly monitoring of coal mining working face gas are presented. The asynchronous correlative characteristics of gas migration in working face airflow direction are qualitatively analyzed. The calculation method of asynchronous correlation delay step and the prediction and inversion formulas of gas concentration changing with time and space after gas emission in the air return roadway are provided. By calculating one hundred and fifty groups of gas sensors data series from a coal mine which have the theoretical correlativity, the correlative coefficient values range of eight kinds of data anomaly is obtained. Then the gas moni- toring data anomaly identification algorithm based on spatio-temporal correlativity analysis is accordingly presented. In order to improve the efficiency of analysis, the gas sensors code rules which can express the spatial topological relations are sug- gested. The experiments indicate that methods presented in this article can effectively compensate the defects of methods based on a single gas sensor monitoring data. 展开更多
关键词 gas monitoring spatio-temporal correlativity analysis anomaly pattern identification ALGORITHM
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Mathematical basis,correlativity and selection of seismicity parameters 被引量:1
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作者 程万正 《Acta Seismologica Sinica(English Edition)》 CSCD 1999年第2期183-187,189-192,共9页
Using the analytic expression of seismicity parameters, the dependency and correlativity between the statisticalparameters and seismic frequency or seismic intensity are discussed. The statistical parameters are divid... Using the analytic expression of seismicity parameters, the dependency and correlativity between the statisticalparameters and seismic frequency or seismic intensity are discussed. The statistical parameters are divided into twokinds. One kind is the regional seismicity parameter, 17 parameters are analyzed in this paper. The other kind isthe seismicity distribution parameter. They are the distribution parameters of time, space and magnitude. The existent base and rationality of distribution parameters depend on the application of distribution model. We analyzeand draw an analogy between the natural probability, Poisson, Weibull distributions and multi-f racial analyticformula in time, space and magnitude. And some examples are given in this paper. The P value and H value of aftershock sequence attenuation, the U value and F value of eanhquake swarm sequence and the entropy of information are discussed preliminarily. Another method about analyzing relationships among time-series curves aregiven. The resemblance relativity degree R,.,, and the relativity degree G,.,, of relative change slope can be usedas the determining values. At last, some preliminary ideas about sifting and using for seismicity parameters are advanced in this paper. 展开更多
关键词 seismicity parameter correlativity EVALUATION
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An Analysis on Correlativity between Large Earthquakes in the Hindu Kush-Pamir and Tienshan Seismic Zone 被引量:1
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作者 Zhang Langping Shao Zhigang 《Earthquake Research in China》 2014年第2期177-187,共11页
In this paper,we introduce the tectonic setting,historical earthquake focal mechanisms and geodynamic environment of Tienshan and its neighboring regions, and draw a conclusion that large earthquakes in the Tienshan s... In this paper,we introduce the tectonic setting,historical earthquake focal mechanisms and geodynamic environment of Tienshan and its neighboring regions, and draw a conclusion that large earthquakes in the Tienshan seismic zone are governed mainly by the pushing from Hindu Kush-Pamir syntax. Secondly,the relationship of large earthquakes in the Hindu Kush-Pamir region and the Tienshan seismic zone is investigated,and synchronization features are found existing in the grouped large earthquakes between the large earthquakes in two regions. The relationship between intermediate-focus large earthquakes in Hindu Kush-Pamir and shallow large earthquakes in the Tienshan seismic zone is also discussed. The same synchronization characteristics are found,and the intensity and frequency of intermediate-focus earthquakes are fiercer, while large earthquakes in the Tienshan seismic zone are more intense,with a wider distribution range. The above results confirm the geodynamic correlativity between Hindu Kush-Pamir and the Tienshan seismic zone from the viewpoint of seismicity. 展开更多
关键词 Tienshan seismic zone Hindu Kush-Pamir Intermediate-focus earthquakes correlativity of large earthquakes
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Study on correlativity among capacity dimension D_0,informationd imension D_1,algorithmic complexityC
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《Acta Seismologica Sinica(English Edition)》 CSCD 1998年第4期507-510,共4页
StudyoncorrelativityamongcapacitydimensionD;,infor-mationdimensionD;,algorithmiccomplexityC(n)andbValueWEI-BI... StudyoncorrelativityamongcapacitydimensionD;,infor-mationdimensionD;,algorithmiccomplexityC(n)andbValueWEI-BINHAN(韩渭宾),GUI-X... 展开更多
关键词 imension correlativity complexityC STUDY AMONG capacity D0 informationd D1 algorithmic
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Study on the correlativity of earthquake's impact on cities
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作者 PAN Hua(潘华) +3 位作者 ZHAO Feng-xin(赵凤新) GAO Meng-tan(高孟潭) 《Acta Seismologica Sinica(English Edition)》 CSCD 2004年第3期362-365,共4页
Introduction  With rapid development and advancement of economy and society, lots of city groups or city belts with ex-tra-large cities as their centers have been formed in China. The regions these city groups lie i... Introduction  With rapid development and advancement of economy and society, lots of city groups or city belts with ex-tra-large cities as their centers have been formed in China. The regions these city groups lie in usually havewell-developed economy, dense population, and are regional politics and culture centers. Some groups lie in theregions with high level of earthquake activity, such as the Surrounding Capital City Group with the centers of Bei-jing and Tianjin. Once a large earthquake occurs, its influence will spread to very extensive region and its disasterwill be tremendous too. So earthquake resistance and disaster mitigation of city group will be very significant issue.The cities in a group have close distance with each other; they can carry out unified preparation for disaster as onewhole and reduce the heavy load of single city before an earthquake, and have an advantage of prompt mutual-aidafter an earthquake because of close distance. It is especially significant to mitigate the lose of lives. One importantprecondition is that all the cities in one group cannot be exposed to the same level of destroy during one earth-quake. So the division of city group in the region with dense cities distribution shall be very significant to theemergent mutual-aid in early time after a large earthquake. For this goal, the characteristics and correlativity ofearthquake′s impact on cities in one group need to clearly be considered. The cities with similar features and strongcorrelativity of historical earthquake influence have large chance to suffer same level destroy during the futurestrong earthquake and are disadvantage to provide mutual-aid and shall not be divided into one group.  …… 展开更多
关键词 city group earthquake impact affected intensity correlativity the simultaneous rate of seismic intensity CLC number: P315.9 Document code: A
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CHAOTIC CONTROL OF NONLINEAR SYSTEMS BASED ON IMPROVED CORRELATIVITY
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作者 Zhou Xiaoan Zhang Jihong (College of Information Eng., Shenzhen University, Shenzhen 518060) 《Journal of Electronics(China)》 2003年第2期132-136,共5页
Chaotic sequences are basically ergodic random sequences. By improving correlativity of a chaotic signal, the chaotic dynamic system can be controlled to converge to its equilibrium point and, more significantly, to i... Chaotic sequences are basically ergodic random sequences. By improving correlativity of a chaotic signal, the chaotic dynamic system can be controlled to converge to its equilibrium point and, more significantly, to its multi-periodic orbits. Mathematical theory analysis is carried out and some computer simulation results are provided to support such controllability of the chaotic Henon system and the discrete coupled map lattice. 展开更多
关键词 Chaotic control correlativity Henon map The coupled map lattice
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Generalized Correlativity of Median Filtering Operator on Signals
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作者 Wanzhou Ye Zhao Liao 《Open Journal of Discrete Mathematics》 2012年第3期83-87,共5页
The generalized correlativity of input signal and output signal of a stack filtering operator is defined and used for numerously measuring these filtering operators's behavior in removing noise in signals. We show... The generalized correlativity of input signal and output signal of a stack filtering operator is defined and used for numerously measuring these filtering operators's behavior in removing noise in signals. We show that under the criterion of the generalized correlativity, of stack filtering operators the median filtering operator is optimal, which implies that this filtering operator possesses better filtering behavior than the others. 展开更多
关键词 MEDIAN FILTER STACK FILTER GENERALIZED correlativity
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Study on correlativity among some seismological prediction indexes related to earthquake frequency or energy
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作者 韩渭宾 易桂喜 辛华 《Acta Seismologica Sinica(English Edition)》 EI CSCD 2001年第6期620-625,共6页
Correlation among various seismological prediction indexes related to earthquake frequency N or energy E for describing seismicity changes is studied by seismic data of 11 seismic zones (areas) in the Sichuan-Yunnan r... Correlation among various seismological prediction indexes related to earthquake frequency N or energy E for describing seismicity changes is studied by seismic data of 11 seismic zones (areas) in the Sichuan-Yunnan region. A statistical test for correlativity shows that seismicity indexes obtained from transformation of earthquake frequency N or energy E have correlation to a certain extent while they are used to describe seismicity changes. If the transformation is linear in all cases, the correlation coefficient is equal to 1. The smaller the transformation deviation from linearity, the bigger the correlation coefficient is. 展开更多
关键词 earthquake frequency earthquake energy seismicity indexes CORRELATION
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SEARCH FOR CORRELATIVITY OF LIGHTNING(STROKE)WITH ATMOSPHERIC STRATIFICATION FACTORS
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作者 张喜轩 张翠华 《Acta meteorologica Sinica》 SCIE 1991年第2期252-252,共1页
In this paper the statistical analysis is carried out on the correlation between lightning strokes and atmospheric stratification factors.It is shown that the total number of strokes in lightning process is mainly dec... In this paper the statistical analysis is carried out on the correlation between lightning strokes and atmospheric stratification factors.It is shown that the total number of strokes in lightning process is mainly decided by environmental temperature at altitude with the residual instability of 5℃(T_r).The instability should also affect the total number of strokc in lightning process.A forecasting equation of stroke in light- ning process has been deduced and two interesting preliminary conclusions have been obtained. 展开更多
关键词 atmospheric stratification INSTABILITY residual instability lightning flashes correlativity
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Correlation between life satisfaction,pleasure level,and negative emotion in patients with chronic renal failure
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作者 Lin-Lin Zhang You-Li Zhang +3 位作者 Ting Liu Jian Wang Chen Chen Xiao-Yu Wang 《World Journal of Psychiatry》 2026年第1期291-298,共8页
BACKGROUND Anxiety,depression,and other negative emotions are common among patients with chronic renal failure(CRF).Analyzing the factors related to negative emotions is necessary to provide targeted nursing care.AIM ... BACKGROUND Anxiety,depression,and other negative emotions are common among patients with chronic renal failure(CRF).Analyzing the factors related to negative emotions is necessary to provide targeted nursing care.AIM To explore the correlations among life satisfaction,pleasure levels,and negative emotions in patients with CRF.METHODS One hundred patients with CRF who received therapy at the First Affiliated Hospital of Jinzhou Medical University between December 2022 and February 2025 were included.The Depression,Anxiety,and Stress Scale(DASS-21),Satisfaction with Life Scale(SWLS),and Temporal Experience of Pleasure Scale(TEPS)were used to evaluate negative emotions,life satisfaction,and pleasure level,respectively.Pearson’s correlation coefficient analyzed the correlation between life satisfaction,pleasure level,and negative emotions.Linear regression analysis identified the factors affecting negative emotions.RESULTS The average DASS-21 score among patients with CRF was 51.90±2.30,with subscale scores of 17.90±1.50 for depression,18.53±1.18 for anxiety,and 15.47±2.36 for stress,all significantly higher than the domestic norm(P<0.05).The average SWLS score was 22.17±4.90.Correlation analysis revealed a negative correlation between the SWLS and total DASS-21 scores(P<0.05),but not with the individual depression,anxiety,or stress dimensions.The average TEPS score was 67.80±8.34.TEPS scores were negatively correlated with the DASS-21 score and the stress dimension(P<0.05),but not with depression or anxiety.Linear regression analysis showed that TEPS scores significantly influenced DASS-21 scores(P<0.05).CONCLUSION Patients with CRF experience high levels of negative emotions,which are negatively correlated with life satisfaction and pleasure.Furthermore,pleasure level had an impact on negative emotions. 展开更多
关键词 Chronic renal failure HEMODIALYSIS Negative emotion Life satisfaction PLEASURE CORRELATION
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Correlativity of nucleosynthesis in low-mass AGB stars
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作者 刘永新 张波 彭秋和 《Science China Mathematics》 SCIE 1996年第10期1112-1120,共9页
In a self-consistent treatment, an LM-AGB TP model of HHe-burning and no-branch reaction passway for s-process from Fe-Bi with correlative reaction network from C-Ne is used to reproduce the enrichment of F, C and hea... In a self-consistent treatment, an LM-AGB TP model of HHe-burning and no-branch reaction passway for s-process from Fe-Bi with correlative reaction network from C-Ne is used to reproduce the enrichment of F, C and heavy elements in the surface of MS and S stars (with Tc). The growing of the core mass and the mass loss through steller winds are also considered. Comparisons between the computed correlation: {[F/O], C/O}; {[F/O], (s/Ti)} and that of the observations are then presented. It appears that fluorine and heavy elements can be synthesized where the nucleosynthesis events occur in a fit temperature range, and then are dredged up to the surface of the star. Because F production only occurs in a narrow temperature range, the synthesis events are sensitive to temperature. The observation of this case is discussed specially. 展开更多
关键词 AGB STARS NUCLEOSYNTHESIS correlation.
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动态劈裂拉伸实验下含双椭圆缺陷花岗岩的动态断裂行为 被引量:3
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作者 徐胜男 彭麟智 +4 位作者 王煦 周星源 王璜 秦浩宸 彭安佳 《科学技术与工程》 北大核心 2025年第6期2218-2226,共9页
为研究含双椭圆缺陷花岗岩的破坏形态及能量耗散规律,利用分离式霍普金森杆(split Hopkinson pressure bar,SHPB)装置,分别对双椭圆缺陷夹角为0°、45°、90°、135°的花岗岩试件进行了动态劈裂拉伸实验,探讨了双椭圆... 为研究含双椭圆缺陷花岗岩的破坏形态及能量耗散规律,利用分离式霍普金森杆(split Hopkinson pressure bar,SHPB)装置,分别对双椭圆缺陷夹角为0°、45°、90°、135°的花岗岩试件进行了动态劈裂拉伸实验,探讨了双椭圆缺陷夹角、缺陷间距与花岗岩破坏形态及能量之间的关系。结果表明:双椭圆缺陷间距不变时,夹角越大,试件越容易断裂;夹角不变时,间距增大,岩样更容易断裂。试件的耗散能密度随夹角的增大而降低,且下降趋势逐渐趋于平缓。试件的破坏形态对夹角的敏感程度较高,即随着夹角的增大,岩样破碎程度逐渐加剧,碎块对称性消失,楔体效应逐渐明显,塑性增强;当夹角超过90°时,破碎程度又开始减小,岩样又呈对称断裂。 展开更多
关键词 冲击荷载 分离式霍普金森杆 DIC(digital image correlation method) 动态断裂 耗散能
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Recent advances in modelling structure-property correlations in high-entropy alloys 被引量:2
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作者 Akash A.Deshmukh Raghavan Ranganathan 《Journal of Materials Science & Technology》 2025年第1期127-151,共25页
Since antiquity,humans have been involved in designing materials through alloying strategies to meet the ever-growing technological demands.In 2004,this endeavor witnessed a significant breakthrough with the discovery... Since antiquity,humans have been involved in designing materials through alloying strategies to meet the ever-growing technological demands.In 2004,this endeavor witnessed a significant breakthrough with the discovery of high-entropy alloys(HEAs)comprising multi-principal elements.Owing to the four“core-effects”,these alloys exhibit exceptional properties including better structural stability,high strength and ductility,improved fatigue/fracture toughness,high corrosion and oxidation resistance,superconductiv-ity,magnetic properties,and good thermal properties.Different synthesis routes have been designed and used to meet the properties of interest for particular applications with varying dimensions.How-ever,HEAs are providing new opportunities and challenges for computational modelling of the complex structure-property correlations and in predictions of phase stability necessary for optimum performance of the alloy.Several attempts have been made to understand these alloys by empirical and computa-tional models,and data-driven approaches to accelerate the materials discovery with a desired set of properties.The present review discusses advances and inferences from simulations and models spanning multiple length and time scales explaining a comprehensive set of structure-properties relations.Addi-tionally,the role of machine learning approaches is also reviewed,underscoring the transformative role of computational modelling in unravelling the multifaceted properties and applications of HEAs,and the scope for future efforts in this direction. 展开更多
关键词 High-entropy alloys DFT Molecular dynamics CALPHAD Machine learning Structure-property correlations
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Utilizing On-the-Go Soil Sensors to Explore Correlations between Electrical Conductivity, Soil Reflectance, Slope, and Elevation of Mississippi Farm Soils 被引量:1
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作者 Reginald S. Fletcher 《Agricultural Sciences》 2025年第1期112-122,共11页
Ten physical and environmental variables collected from an on-the-go soil sensor at two field sites (MF3E and MF11S) in Mississippi, USA, were analyzed to assess soil variability and the interrelationships among the m... Ten physical and environmental variables collected from an on-the-go soil sensor at two field sites (MF3E and MF11S) in Mississippi, USA, were analyzed to assess soil variability and the interrelationships among the measurements. At MF3E, moderate variability was observed in apparent electrical conductivity shallow (ECas), slope, and ECa ratio measurements, with coefficients of variation ranging from 20% to 27%. In contrast, MF11S exhibited higher variability, particularly in ECas and ECad (deep) measurements, which exceeded 30% in their coefficient of variation values, indicating significant differences in soil composition and moisture content. Correlation analysis revealed strong positive relationships between the near-infrared-to-red ratio and red reflectance (r = 0.897***) soil values at MF3E. MF11S demonstrated a strong negative correlation between ECas and ECad readings with the x-coordinate (r ***). Scatter plots and fitted models illustrated the complexity of relationships, with many showing nonlinear trends. These findings emphasize the need for continuous monitoring and advanced modeling to understand the dynamic nature of soil properties and their implications for agricultural practices. Future research should explore the underlying mechanisms driving variability in the soil characteristics to enhance soil management strategies at the study sites. 展开更多
关键词 Mobile Soil Sensors NEAR-INFRARED Correlation Nonlinear
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Correlated factors of posttraumatic growth in patients with colorectal cancer:A systematic review and meta-analysis 被引量:1
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作者 Dingyuan Wei Xue Wang +4 位作者 Mengxing Wang Jiayan Wang Fangping Chen Luyang Jin Xuemei Xian 《International Journal of Nursing Sciences》 2025年第1期96-105,I0005,共11页
Objectives:This systematic review and meta-analysis aimed to identify and synthesize the factors correlated with posttraumatic growth(PTG)in patients with colorectal cancer(CRC).Methods:PubMed,Web of Science,Embase,Ps... Objectives:This systematic review and meta-analysis aimed to identify and synthesize the factors correlated with posttraumatic growth(PTG)in patients with colorectal cancer(CRC).Methods:PubMed,Web of Science,Embase,PsycINFO,CINAHL,Cochrane Library,China National Knowledge Infrastructure(CNKI),Wanfang database,China Science and Technology Journal Database(VIP)and SinoMed were searched for studies that reported data on the correlated factors associated with PTG in patients with CRC from inception to September 3,2024.The methodological quality of the included studies was assessed via the Agency for Healthcare Research and Quality(AHRQ)methodology checklist and the Newcastle-Ottawa Scale(NOS).Pearson correlation coefficient(r)was utilized to indicate effect size.Meta-analysis was conducted in R Studio.Results:Thirty-one eligible studies encompassing 6,400 participants were included in this review.Correlated factors were identified to be significantly associated with PTG in patients with CRC including demographic factors:residential area(r=0.13),marital status(r=0.10),employment status(r=0.18),education level(r=0.19),income level(r=0.16);disease-related factors:time since surgery(r=0.17),stoma-related complications(r=0.14),health-promoting behavior(r=0.46),and sexual function(r=0.17);psychosocial factors:confrontation coping(r=0.68),avoidance coping(r=-0.65),deliberate rumination(r=0.56),social support(r=0.47),family function(r=0.50),resilience(r=0.53),selfefficacy(r=0.91),self-compassion(r=-0.32),psychosocial adjustment(r=0.39),gratitude(r=0.45),stigma(r=-0.65),self-perceived burden(r=-0.31),fear of cancer recurrence(r=-0.45);and quality of life(r=0.32).Conclusions:This meta-analysis identified 23 factors associated with PTG in CRC patients.Medical workers can combine those relevant factors from the perspective of positive psychology,further explore the occurrence and development mechanism of PTG,and establish targeted interventions to promote PTG. 展开更多
关键词 Colorectal cancer Correlated factors META-ANALYSIS Posttraumatic growth Positive psychology
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Correlations of resilience with coping styles and quality of life in patients with malignancies 被引量:1
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作者 Xue-Jin Qin Man-Man Kang +4 位作者 Fei Zhong Jing-Jing Liu Zheng-Chun Zhu Di Zhang Ke Han 《World Journal of Psychiatry》 2025年第4期186-194,共9页
BACKGROUND Resilience is an individual’s ability and psychological rebound capacity to adapt well after experiencing adversity,trauma,etc.Patients with strong resilience can face illnesses actively.AIM To determine t... BACKGROUND Resilience is an individual’s ability and psychological rebound capacity to adapt well after experiencing adversity,trauma,etc.Patients with strong resilience can face illnesses actively.AIM To determine the association of resilience with coping styles and quality of life in patients with malignancies.METHODS This study included patients with malignant tumors who were hospitalized at Fuyang Hospital Affiliated to Anhui Medical University from March 2022 to March 2024.The Connor-Davidson Resilience Scale,Medical Coping Modes Questionnaire,Social Support Rating Scale,and the European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire Core 30 were utilized to assess patients’resilience,coping styles,social support,and quality of life,respectively.Pearson correlation analysis was conducted to assess the correlations.RESULTS A total of 175 patients with malignant tumors demonstrated no marked difference in terms of age,education level,employment status,monthly household income,and disease staging(P<0.05).Further,patients with malignancies demonstrated scores of 17.49±1.20,17.27±1.46,and 11.19±1.29 points in terms of coping styles in confrontation,avoidance,and resignation dimensions,respectively.Subjective support,objective support,and support utilization scores in terms of social support were 10.67±1.80,11.26±2.08,and 9.24±1.14 points,respectively.The total resilience score and tenacity,self-improvement,and optimism dimension scores were positively correlatedwith the confrontation coping style score,whereas the total resilience score and tenacity and self-improvementscores were negatively associated with avoidance and resignation coping style scores(P<0.05).The total resiliencescore and the tenacity dimension score were positively associated with physical,role,cognitive,emotional,andsocial functions,as well as global health status(P<0.05),and were inversely related to fatigue,insomnia,andeconomic difficulties(P<0.05).CONCLUSIONThe resilience of patients with malignancies is positively associated with the confrontation dimension in the copingstyle,the total and various social support domain scores,and the overall quality of life.Clinical medical staff needto pay attention to the effect of medical coping styles and social support on the resilience level of patients withmalignancies to further improve their quality of life. 展开更多
关键词 Malignant tumor RESILIENCE Coping style Quality of life CORRELATION
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A correlation study of selected geomagnetic events recorded by the Egyptian observatories and INTERMAGNET stations 被引量:1
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作者 Aalaa Samy Tarek Arafa-Hamed +2 位作者 Abdou Abdelkader Ahmed Khashaba Emad Takla 《Earthquake Science》 2025年第2期81-92,共12页
Geomagnetic observatory data are crucial for all branches of geophysics because they can contribute to earthquake research by detecting anomalies in the Earth’s magnetic field.Recently,data records from the Misallat(... Geomagnetic observatory data are crucial for all branches of geophysics because they can contribute to earthquake research by detecting anomalies in the Earth’s magnetic field.Recently,data records from the Misallat(MLT)and Abu Simbel(ABS)Egyptian geomagnetic observatories were processed and found to be of good quality.In this study,Egyptian observatory data were tested during both quiet and disturbed events and compared with data from INTERMAGNET observatories worldwide at different latitudes and within a narrow range of longitudes in both hemispheres.This study investigated the relationships between magnetic field components from Egyptian observatories and those from INTERMAGNET observatories using graphical representations of the X components;Pearson’s correlation for the X,Y,Z,and F components;cross-correlation for the X component;and wavelet coherence for the F component.The results of this study showed a high correlation between Egyptian observatories and all utilized INTERMAGNET stations,except those located at high latitudes,during both quiet and disturbed events.Additionally,the study confirmed the observed consistency between Egyptian observatories and selected INTERMAGNET stations.Therefore,Egyptian observatories can feasibly fill the gap in the Middle East and North Africa. 展开更多
关键词 Egyptian geomagnetic observatories correlation wavelet coherence INTERMAGNET
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Detailed oil-source correlation within the sequence and sedimentary framework in the Fushan Depression,Beibuwan Basin,South China Sea 被引量:1
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作者 Xin Wang Mei-Jun Li +3 位作者 Yang Shi Hao Guo Bang Zeng Xi He 《Petroleum Science》 2025年第1期90-109,共20页
The Fushan Depression is one of the petroliferous depressions in the Beibuwan Basin,South China Sea.Previous studies have preliminarily explored the origin and source of crude oils in some areas of this depression.Nev... The Fushan Depression is one of the petroliferous depressions in the Beibuwan Basin,South China Sea.Previous studies have preliminarily explored the origin and source of crude oils in some areas of this depression.Nevertheless,no systematic investigations on the classification and origin of oils and hy-drocarbon migration processes have been made for the entire petroleum system in this depression,which has significantly hindered the hydrocarbon exploration in the region.A total of 32 mudstone and 58 oil samples from the Fushan Depression were analyzed to definite the detailed oil-source correlation within the sequence and sedimentary framework.The organic matter of third member of Paleogene Liushagang Formation(Els(3))source rocks,both deltaic and lacustrine mudstone,are algal-dominated with high abundance of C_(23)tricyclic terpane and C_(30)4-methylsteranes.The deltaic source rocks occur-ring in the first member(Els_(1))and second member(Els_(2))of the Paleogene Liushagang Formation are characterized by high abundance of C_(19+20)tricyclic terpane and oleanane,reflecting a more terrestrial plants contribution.While lacustrine source rocks of Els_(1)and Els_(2)display the reduced input of terrige-nous organic matter with relatively low abundance of C 19+20 tricyclic terpane and oleanane.Three types of oils were identified by their biomarker compositions in this study.Most of the oils discovered in the Huachang and Bailian Els_(1)reservoir belong to group A and were derived from lacustrine source rocks of Els_(1)and Els_(2).Group B oils are found within the Els_(1)and Els_(2)reservoirs,showing a close relation to the deltaic source rocks of Els_(1)and Els_(2),respectively.Group C oils,occurring in the Els3 reservoirs,have a good affinity with the Els3 source rocks.The spatial distribution and accumulation of different groups of oils are mainly controlled by the sedimentary facies and specific structural conditions.The Els_(2)reservoir in the Yong'an area belonging to Group B oil,are adjacent to the source kitchen and could be considered as the favorable exploration area in the future. 展开更多
关键词 Oil-source correlation Sequence stratigraphic framework Biomarkers Fushan depression South China Sea
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Impact of Dataset Size on Machine Learning Regression Accuracy in Solar Power Prediction 被引量:1
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作者 S.M.Rezaul Karim Md.Shouquat Hossain +3 位作者 Khadiza Akter Debasish Sarker Md.Moniul Kabir Mamdouh Assad 《Energy Engineering》 2025年第8期3041-3054,共14页
Knowing the influence of the size of datasets for regression models can help in improving the accuracy of a solar power forecast and make the most out of renewable energy systems.This research explores the influence o... Knowing the influence of the size of datasets for regression models can help in improving the accuracy of a solar power forecast and make the most out of renewable energy systems.This research explores the influence of dataset size on the accuracy and reliability of regression models for solar power prediction,contributing to better forecasting methods.The study analyzes data from two solar panels,aSiMicro03036 and aSiTandem72-46,over 7,14,17,21,28,and 38 days,with each dataset comprising five independent and one dependent parameter,and split 80–20 for training and testing.Results indicate that Random Forest consistently outperforms other models,achieving the highest correlation coefficient of 0.9822 and the lowest Mean Absolute Error(MAE)of 2.0544 on the aSiTandem72-46 panel with 21 days of data.For the aSiMicro03036 panel,the best MAE of 4.2978 was reached using the k-Nearest Neighbor(k-NN)algorithm,which was set up as instance-based k-Nearest neighbors(IBk)in Weka after being trained on 17 days of data.Regression performance for most models(excluding IBk)stabilizes at 14 days or more.Compared to the 7-day dataset,increasing to 21 days reduced the MAE by around 20%and improved correlation coefficients by around 2.1%,highlighting the value of moderate dataset expansion.These findings suggest that datasets spanning 17 to 21 days,with 80%used for training,can significantly enhance the predictive accuracy of solar power generation models. 展开更多
关键词 Correlation coefficients dataset size machine learning mean absolute error regression solar power prediction
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Construction and characteristic analysis of background error covariance coupled with land surface temperature 被引量:1
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作者 Qihang Yang Yaodeng Chen +4 位作者 Luyao Qin Yuanbing Wang Deming Meng Xusheng Yan Xinyao Qian 《Atmospheric and Oceanic Science Letters》 2025年第3期7-12,共6页
Land surface temperature(LST)is the key variable in land-atmosphere interaction,having an important impact on weather and climate forecasting.However,achieving consistent analysis of LST and the atmosphere in assimila... Land surface temperature(LST)is the key variable in land-atmosphere interaction,having an important impact on weather and climate forecasting.However,achieving consistent analysis of LST and the atmosphere in assimilation is quite challenging.This is because there is limited knowledge about the cross-component background error covariance(BEC)between LST and atmospheric state variables.This study aims to clarify whether there is a relationship between the error of LST and atmospheric variables,and whether this relationship varies spatially and temporally.To this end,the BEC coupled with atmospheric variables and LST was constructed(LST-BEC),and its characteristics were analyzed based on the 2023 mei-yu season.The general characteristics of LST-BEC show that the LST is mainly correlated with the atmospheric temperature and the correlation decreases gradually with a rise in atmospheric height,and the error standard deviation of the LST is noticeably larger than that of the low-level atmospheric temperature.The spatiotemporal characteristics of LST-BEC on the heavy-rain day and light-rain day show that the error correlation and error standard deviation of LST and low-level atmospheric temperature and humidity are closely related to the weather background,and also have obvious diurnal variations.These results provide valuable information for strongly coupled land-atmosphere assimilation. 展开更多
关键词 Background error covariance Land surface temperature Error correlation Error standard deviation Data assimilation
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