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Improved statistical fluctuation analysis for two decoy-states phase-matching quantum key distribution
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作者 周江平 周媛媛 +1 位作者 周学军 暴轩 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第8期188-194,共7页
Phase-matching quantum key distribution is a promising scheme for remote quantum key distribution,breaking through the traditional linear key-rate bound.In practical applications,finite data size can cause significant... Phase-matching quantum key distribution is a promising scheme for remote quantum key distribution,breaking through the traditional linear key-rate bound.In practical applications,finite data size can cause significant system performance to deteriorate when data size is below 1010.In this work,an improved statistical fluctuation analysis method is applied for the first time to two decoy-states phase-matching quantum key distribution,offering a new insight and potential solutions for improving the key generation rate and the maximum transmission distance while maintaining security.Moreover,we also compare the influence of the proposed improved statistical fluctuation analysis method on system performance with those of the Gaussian approximation and Chernoff-Hoeffding boundary methods on system performance.The simulation results show that the proposed scheme significantly improves the key generation rate and maximum transmission distance in comparison with the Chernoff-Hoeffding approach,and approach the results obtained when the Gaussian approximation is employed.At the same time,the proposed scheme retains the same security level as the Chernoff-Hoeffding method,and is even more secure than the Gaussian approximation. 展开更多
关键词 quantum key distribution phase matching protocol statistical fluctuation analysis decoy state
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Statistical analysis on the influence of mechanical parameters in the vibration of pylons
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作者 Georgios I.Dadoulis George D.Manolis 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2023年第1期263-278,共16页
We present a statistical investigation of the degree of influence that assumptions made in relation to the mechanical parameters of a pylon have on its ground-induced vibrations.The study is set up by using as a key k... We present a statistical investigation of the degree of influence that assumptions made in relation to the mechanical parameters of a pylon have on its ground-induced vibrations.The study is set up by using as a key kinematic variable the displacement at the top of a reference,a stand-alone pylon with a uniform cross-section and fixity at its base.Next,statistics are produced using a dimensionless displacement ratio defined between the‘parental’and the‘subsidiary’cases,the latter defined for the pylon(a)resting on compliant soil,(b)having an attached top mass,and(c)being non-uniform with height.Furthermore,two materials are examined,namely,steel and reinforced concrete(R/C).More specifically,this displacement ratio is independent of the excitation and plays the role of a transfer function between the base and the top of the pylon.Both horizontal and vertical motions are considered,and the equations of motion are solved in the frequency domain.The ensuing statistical analysis is conducted for the following parameter combinations:(a)pylon founded on soft,intermediate,and stiff soil;(b)low,intermediate,and high-mass ratios of the attached mass to the pylon′s mass;(c)a constant and quadratic degree of pylon tapering with height.Spearman correlation coefficients are calculated for all the above combinations to arrive at statistical results that establish validity bounds and quantify the degree of influence of each assumption on the pylon′s response. 展开更多
关键词 pylons statistical analysis spearman coefficients structural vibrations elastic waveguides attached masses soil springs TAPERING
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Effect of Jianpi Bushen formula for colon cancer patients who underwent adjuvant chemotherapy:Statistical analysis plan for a multicenter trial
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作者 Ruiming Zhao Huijuan Cao +7 位作者 Lingyun Sun Tong Zhang Yun Xu Shaohua Yan Jun Mao Jianping Liu Yutong Fei Yufei Yang 《Journal of Traditional Chinese Medical Sciences》 CAS 2023年第1期58-63,共6页
Background:Patients with colon cancer who receive chemotherapy usually experience various gastrointestinal adverse reactions,including nausea,vomiting,and diarrhea,which make it challenging for them to adhere to treat... Background:Patients with colon cancer who receive chemotherapy usually experience various gastrointestinal adverse reactions,including nausea,vomiting,and diarrhea,which make it challenging for them to adhere to treatment.As an effective traditional Chinese medicine,the Jianpi Bushen formula has been widely used to alleviate the side effects of chemotherapy.Objective:To evaluate the efficacy and safety of Jianpi Bushen formulae for patients who undergo chemotherapy.This statistical analysis plan(SAP)is intended to enhance the transparency and research quality of our randomized controlled trial.Methods:Our study is a multicenter,double-blind,randomized controlled clinical trial.This trial aimed to compare the completion rate of chemotherapy in colon cancer patients who are using and not using Jianpi Bushen formula.To attenuate possible selection bias in the final report,we declared the overall trial design,outcome measures,subgroup analyses,and safety measures.Also,we described the data management and statistical analysis methods in detail.Conclusion:The SAP provides more detailed information than the trial protocol for data management and statistical analysis methods.Further post-hoc analyses can be performed by referring to the SAP,and possible selection bias can be attenuated. 展开更多
关键词 statistical analysis plan Colon cancer CHEMOTHERAPY Randomized controlled trial Traditional Chinese medicine CAPECITABINE OXALIPLATIN Treatment duration
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Statistical Analysis and Countermeasures for Specimen Rejection in the Emergency Department
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作者 Yinhua Fan Bo Zhao 《Journal of Clinical and Nursing Research》 2023年第4期145-150,共6页
The rejected specimens from the Emergency Department of the Center of Clinical Laboratory from January 1,2022 to January 1,2023 were analyzed to reduce the specimen rejection rates and to improve the quality of inspec... The rejected specimens from the Emergency Department of the Center of Clinical Laboratory from January 1,2022 to January 1,2023 were analyzed to reduce the specimen rejection rates and to improve the quality of inspection.The results showed that there were 1488 samples of rejected specimens and the non-conforming rate was 0.58%.The departments involved were mainly the Emergency Department,the Hematology Department,the Cardiology Department,the Intensive Care Department,and the Brain Surgery Department.Among the reasons for rejection,blood hemolysis accounted for 43.15%,blood coagulation accounted for 26.61%,and the rate of insufficient specimens was 17.14%.Among them,the sample rejection rate for arterial blood gas analysis was the highest,which accounted for 1.74%;followed by specimens for coagulation test,which was 1.18%.These results indicate the main reason for producing rejected specimens is mainly due to not following the standard operating procedure.Specimen rejection can largely be avoided if the standards for specimen collection are strictly followed. 展开更多
关键词 Specimen rejection statistical analysis Quality inspection
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A Statistical Analysis on Papers and Authors in Wuhan University Journal of Natural Sciences in 2003
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作者 HUMin 《Wuhan University Journal of Natural Sciences》 CAS 2004年第6期983-986,共4页
The author of this article counts and analyzes the papers and authors printed in 2003 Wuhan University Journal of Natural Sciences by means of bibliometric statistical methods, of which the characteristics of papers a... The author of this article counts and analyzes the papers and authors printed in 2003 Wuhan University Journal of Natural Sciences by means of bibliometric statistical methods, of which the characteristics of papers and authors are expounded. The result shows that the ratio of reprinting of this journal has been increased and the areas where the authors come from and their organization scattered in the whole world are widened as well, which implies a better-known fame of the journal. Key words Wuhan University Journal of Natural Sciences - papers analysis - authors analysis - statistical analysis CLC number G 353.1 Biography: HU Min(1961-), famale, Associate professor, research direction; editing science and biochemistry. 展开更多
关键词 Wuhan University Journal of Natural sciences papers analysis authors analysis statistical analysis
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North Atlantic Oscillation and Rainfall Variability in Southeastern Nigeria:A Statistical Analysis of 30 Year Period
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作者 Okorie Fidelis Chinazor 《Journal of Atmospheric Science Research》 2021年第4期42-49,共8页
This study analyzed rainfall variability in Southeast region of Nigeria using graphical models,as well as using statistical approach to investigate any significant relationship between the global North Atlantic Oscill... This study analyzed rainfall variability in Southeast region of Nigeria using graphical models,as well as using statistical approach to investigate any significant relationship between the global North Atlantic Oscillation(NAO)Index and the regional rainfall variability in region.The study was conducted in three States of Southeastern Nigeria namely,Abia,Ebonyi and Imo States that lie between Latitudes 4040’and 8050’N and Longitudes 6020’and 8050’E.Data for the study included 30 years(1988-2017)archival time-series monthly rainfall values for the three study States,acquired from Nigerian Meteorological Agency(NIMET),offices in the states,and Standardized values of NAOI(North Atlantic Oscillation Index)for the same period,which were collected from a website,on the NOAA Data Center,USA.In the data analyses,the first method was adopted by using graphs to illustrate mean annual rainfall values for thirty years.Coefficient of variability was employed in evaluating the degree of variability of values from the mean rate.The second analysis was accomplished using correlation models to ascertain any relationship between NAOI and rainfall in Southeast Nigeria.The results showed a significant variability of rainfall in the region from January to December(mean monthly)within the study period.A negative correlation value of 0.7525 was obtained from the correlation analysis,showing that the global NAO index and rainfall variability deviate in the opposite direction.Coefficient of multiple determinations(CMD)subsequently showed value of 0.031%,being the variation in rainfall as influenced by the global teleconnectivity,and this means that the NAO index has zero or no influence on rainfall variability in Southeast region of Nigeria. 展开更多
关键词 NAO Rainfall variability RELATIONSHIP statistical analysis Southeastern Nigeria
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Quantitative analysis and prediction of the sound field convergence zone in mesoscale eddy environment based on data mining methods
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作者 Ming Li Yuhang Liu +1 位作者 Yiyuan Sun Kefeng Liu 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2024年第5期110-120,共11页
The mesoscale eddy(ME)has a significant influence on the convergence effect in deep-sea acoustic propagation.This paper use statistical approaches to express quantitative relationships between the ME conditions and co... The mesoscale eddy(ME)has a significant influence on the convergence effect in deep-sea acoustic propagation.This paper use statistical approaches to express quantitative relationships between the ME conditions and convergence zone(CZ)characteristics.Based on the Gaussian vortex model,we construct various sound propagation scenarios under different eddy conditions,and carry out sound propagation experiments to obtain simulation samples.With a large number of samples,we first adopt the unified regression to set up analytic relationships between eddy conditions and CZ parameters.The sensitivity of eddy indicators to the CZ is quantitatively analyzed.Then,we adopt the machine learning(ML)algorithms to establish prediction models of CZ parameters by exploring the nonlinear relationships between multiple ME indicators and CZ parameters.Through the research,we can express the influence of ME on the CZ quantitatively,and achieve the rapid prediction of CZ parameters in ocean eddies.The prediction accuracy(R)of the CZ distance(mean R:0.9815)is obviously better than that of the CZ width(mean R:0.8728).Among the three ML algorithms,Gradient Boosting Decision Tree has the best prediction ability(root mean square error(RMSE):0.136),followed by Random Forest(RMSE:0.441)and Extreme Learning Machine(RMSE:0.518). 展开更多
关键词 convergence zone mesoscale eddy statistic analysis quantitative prediction machine learning
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A Bayesian multi-model inference methodology for imprecise momentindependent global sensitivity analysis of rock structures
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作者 Akshay Kumar Gaurav Tiwari 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第3期840-859,共20页
Traditional global sensitivity analysis(GSA)neglects the epistemic uncertainties associated with the probabilistic characteristics(i.e.type of distribution type and its parameters)of input rock properties emanating du... Traditional global sensitivity analysis(GSA)neglects the epistemic uncertainties associated with the probabilistic characteristics(i.e.type of distribution type and its parameters)of input rock properties emanating due to the small size of datasets while mapping the relative importance of properties to the model response.This paper proposes an augmented Bayesian multi-model inference(BMMI)coupled with GSA methodology(BMMI-GSA)to address this issue by estimating the imprecision in the momentindependent sensitivity indices of rock structures arising from the small size of input data.The methodology employs BMMI to quantify the epistemic uncertainties associated with model type and parameters of input properties.The estimated uncertainties are propagated in estimating imprecision in moment-independent Borgonovo’s indices by employing a reweighting approach on candidate probabilistic models.The proposed methodology is showcased for a rock slope prone to stress-controlled failure in the Himalayan region of India.The proposed methodology was superior to the conventional GSA(neglects all epistemic uncertainties)and Bayesian coupled GSA(B-GSA)(neglects model uncertainty)due to its capability to incorporate the uncertainties in both model type and parameters of properties.Imprecise Borgonovo’s indices estimated via proposed methodology provide the confidence intervals of the sensitivity indices instead of their fixed-point estimates,which makes the user more informed in the data collection efforts.Analyses performed with the varying sample sizes suggested that the uncertainties in sensitivity indices reduce significantly with the increasing sample sizes.The accurate importance ranking of properties was only possible via samples of large sizes.Further,the impact of the prior knowledge in terms of prior ranges and distributions was significant;hence,any related assumption should be made carefully. 展开更多
关键词 Bayesian inference Multi-model inference statistical uncertainty Global sensitivity analysis(GSA) Borgonovo’s indices Limited data
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Statistical Approach to Basketball Players’Skill Level
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作者 Jiajun Wu 《Journal of Applied Mathematics and Physics》 2024年第4期1352-1363,共12页
In basketball, each player’s skill level is the key to a team’s success or failure, the skill level is affected by many personal and environmental factors. A physics-informed AI statistics has become extremely impor... In basketball, each player’s skill level is the key to a team’s success or failure, the skill level is affected by many personal and environmental factors. A physics-informed AI statistics has become extremely important. In this article, a complex non-linear process is considered by taking into account the average points per game of each player, playing time, shooting percentage, and others. This physics-informed statistics is to construct a multiple linear regression model with physics-informed neural networks. Based on the official data provided by the American Basketball League, and combined with specific methods of R program analysis, the regression model affecting the player’s average points per game is verified, and the key factors affecting the player’s average points per game are finally elucidated. The paper provides a novel window for coaches to make meaningful in-game adjustments to team members. 展开更多
关键词 Physics-Informed statistics Multiple Linear Regression Average Score per Game R Program analysis
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A Survey of Statistical Analysis in a Selected M.A. Dissertation
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作者 付慧平 《科技信息》 2010年第6期172-174,共3页
The use of statistics has received increasing attention in the studies of linguistics and applied linguistics. However,due to its complexity and preciseness,there are many problems of application of statistics. The pr... The use of statistics has received increasing attention in the studies of linguistics and applied linguistics. However,due to its complexity and preciseness,there are many problems of application of statistics. The present paper tries to discuss the application of statistics in a M.A. dissertation and aims to explain how to apply statistics to linguistics research normatively,scientifically,and precisely. 展开更多
关键词 英语 应用语言学 学习方法 统计数字
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Simulation on a Car Interior Aerodynamic Noise Control Based on Statistical Energy Analysis 被引量:5
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作者 CHEN Xin WANG Dengfeng MA Zhengdong 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2012年第5期1016-1021,共6页
How to simulate interior aerodynamic noise accurately is an important question of a car interior noise reduction. The unsteady aerodynamic pressure on body surfaces is proved to be the key effect factor of car interio... How to simulate interior aerodynamic noise accurately is an important question of a car interior noise reduction. The unsteady aerodynamic pressure on body surfaces is proved to be the key effect factor of car interior aerodynamic noise control in high frequency on high speed. In this paper, a detail statistical energy analysis (SEA) model is built. And the vibra-acoustic power inputs are loaded on the model for the valid result of car interior noise analysis. The model is the solid foundation for further optimization on car interior noise control. After the most sensitive subsystems for the power contribution to car interior noise are pointed by SEA comprehensive analysis, the sound pressure level of car interior aerodynamic noise can be reduced by improving their sound and damping characteristics. The further vehicle testing results show that it is available to improve the interior acoustic performance by using detailed SEA model, which comprised by more than 80 subsystems, with the unsteady aerodynamic pressure calculation on body surfaces and the materials improvement of sound/damping properties. It is able to acquire more than 2 dB reduction on the central frequency in the spectrum over 800 Hz. The proposed optimization method can be looked as a reference of car interior aerodynamic noise control by the detail SEA model integrated unsteady computational fluid dynamics (CFD) and sensitivity analysis of acoustic contribution. 展开更多
关键词 CAR interior aerodynamic noise CONTROL computational fluid dynamics statistical energy analysis
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STATISTICAL ANALYSIS AND NUMERICAL SIMULATION OF POYANG LAKE'S INFLUENCE ON TROPICAL CYCLONES 被引量:6
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作者 张胜军 陈联寿 李英 《Journal of Tropical Meteorology》 SCIE 2012年第2期249-262,共14页
Based on the Tropical Cyclone(TC briefly thereafter)Yearbook 1980-2009,this paper first analyzes the number and intensity change of the TCs which passed directly over or by the side of Poyang Lake(the distance of TC c... Based on the Tropical Cyclone(TC briefly thereafter)Yearbook 1980-2009,this paper first analyzes the number and intensity change of the TCs which passed directly over or by the side of Poyang Lake(the distance of TC center is less than 1°longitude or 1°latitude from the Lake)among all the landfalling TCs in China during the past 30 years.Two cases are examined in detail in this paper.One is severe typhoon Rananim with a speed of 3.26 m/s and a change of 1 hPa in intensity when it was passing the Lake.The other is super typhoon Saomai with a faster moving speed of 6.50 m/s and a larger change in intensity of 6 hPa.Through numerical simulation experiments,this paper analyzes how the change of underlying surface from water to land contributes to the differences in intensity,speed and mesoscale convection of the two TCs when they passed the Lake.Results show that the moisture and dynamic condition above the Lake were favorable for the maintenance of the intensity when Rananim was passing through Poyang Lake,despite the moisture supply from the ocean was cut off.As a result,there was strong convection around the lake which led to a rainfall spinning counter-clockwise as it was affected by the TC movement.However,little impact was seen in the Saomai case.These results indicate that for the TCs coming ashore on Poyang Lake with a slow speed,the large water body is conducive to the sustaining of the intensity and strengthening of the convection around the TC center and the subsequent heavy rainfall.On the contrary,a fast-moving TC is less likely to be influenced by the underlying surface in terms of intensity and speed. 展开更多
关键词 tropical cyclone LANDFALL statistical analysis numerical simulation Poyang Lake
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GREY RELATIONAL ANALYSIS: A NEW STATISTICAL METHOD OF MULTIFACTORIAL ANALYSIS IN MEDICINE 被引量:4
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作者 谭学瑞 邓聚龙 《Journal of Pharmaceutical Analysis》 CAS 1997年第1期59-65,共7页
The concept, fundamental theory, analytical steps and formulae of grey relational analysis (GRA)-a new statistical method or multifactorial analysis in the field of medicine were introduced. GRA of grouping sequence t... The concept, fundamental theory, analytical steps and formulae of grey relational analysis (GRA)-a new statistical method or multifactorial analysis in the field of medicine were introduced. GRA of grouping sequence that is applied to medical study was built by the authors. An example was given to demonstrate it. The superiority of GRA was recounted briefly. 展开更多
关键词 grey relational analysis multifactorial analysis statistICS MEDICINE
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Application of Statistical Tools for Data Analysis and Interpretation in Rice Plant Pathology 被引量:2
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作者 Parsuram NAYAK Arup Kumar MUKHERJEE +1 位作者 Elssa PANDIT Sharat Kumar PRADHAN 《Rice science》 SCIE CSCD 2018年第1期1-18,共18页
There has been a significant advancement in the application of statistical tools in plant pathology during the past four decades. These tools include multivariate analysis of disease dynamics involving principal compo... There has been a significant advancement in the application of statistical tools in plant pathology during the past four decades. These tools include multivariate analysis of disease dynamics involving principal component analysis, cluster analysis, factor analysis, pattern analysis, discriminant analysis, multivariate analysis of variance, correspondence analysis, canonical correlation analysis, redundancy analysis, genetic diversity analysis, and stability analysis, which involve in joint regression, additive main effects and multiplicative interactions, and genotype-by-environment interaction biplot analysis. The advanced statistical tools, such as non-parametric analysis of disease association, meta-analysis, Bayesian analysis, and decision theory, take an important place in analysis of disease dynamics. Disease forecasting methods by simulation models for plant diseases have a great potentiality in practical disease control strategies. Common mathematical tools such as monomolecular, exponential, logistic, Gompertz and linked differential equations take an important place in growth curve analysis of disease epidemics. The highly informative means of displaying a range of numerical data through construction of box and whisker plots has been suggested. The probable applications of recent advanced tools of linear and non-linear mixed models like the linear mixed model, generalized linear model, and generalized linear mixed models have been presented. The most recent technologies such as micro-array analysis, though cost effective, provide estimates of gene expressions for thousands of genes simultaneously and need attention by the molecular biologists. Some of these advanced tools can be well applied in different branches of rice research, including crop improvement, crop production, crop protection, social sciences as well as agricultural engineering. The rice research scientists should take advantage of these new opportunities adequately in adoption of the new highly potential advanced technologies while planning experimental designs, data collection, analysis and interpretation of their research data sets. 展开更多
关键词 statistical tool PLANT PATHOLOGY data analysis multivariate analysis NON-PARAMETRIC analysis MICRO-ARRAY analysis decision theory PLANT disease EPIDEMICS rice
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Identification of distant co-evolving residues in antigen 85C from Mycobacterium tuberculosis using statistical coupling analysis of the esterase family proteins 被引量:2
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作者 Veeky Baths Utpal Roy 《The Journal of Biomedical Research》 CAS 2011年第3期165-169,共5页
A fundamental goal in cellular signaling is to understand allosteric communication, the process by which sig-nals originating at one site in a protein propagate reliably to affect distant functional sites. The general... A fundamental goal in cellular signaling is to understand allosteric communication, the process by which sig-nals originating at one site in a protein propagate reliably to affect distant functional sites. The general principles of protein structure that underlie this process remain unknown. Statistical coupling analysis (SCA) is a statistical technique that uses evolutionary data of a protein family to measure correlation between distant functional sites and suggests allosteric communication. In proteins, very distant and small interactions between collections of amino acids provide the communication which can be important for signaling process. In this paper, we present the SCA of protein alignment of the esterase family (pfam ID: PF00756) containing the sequence of antigen 85C secreted by Mycobacterium tuberculosis to identify a subset of interacting residues. Clustering analysis of the pairwise correlation highlighted seven important residue positions in the esterase family alignments. These resi-dues were then mapped on the crystal structure of antigen 85C (PDB ID: 1DQZ). The mapping revealed corre-lation between 3 distant residues (Asp38, Leu123 and Met125) and suggests allosteric communication between them. This information can be used for a new drug against this fatal disease. 展开更多
关键词 antigen 85C Mycobacterium tuberculosis clustering analysis COVARIANCE statistical coupling analy-sis esterase family multiple sequence alignments PFAM Protein Data Bank.
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Solar term peak of onset and death in 1 597 patients with acute ischemic stroke Circular statistical analysis 被引量:1
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作者 Mingfeng He Zhangrong Liang +7 位作者 Jiping Zhang Zhenhe Gao Shaoyong Mo Yingjian Zhang Fang Shen Zixing Chen Liyun Cai Weihong Xiang 《Neural Regeneration Research》 SCIE CAS CSCD 2007年第9期532-535,共4页
BACKGROUND: Previously, time data were analyzed by using constituent ratio or relative ratio; however, circular statistical analysis could exactly provide average peak phase of diseases. OBJECTIVE: To investigate th... BACKGROUND: Previously, time data were analyzed by using constituent ratio or relative ratio; however, circular statistical analysis could exactly provide average peak phase of diseases. OBJECTIVE: To investigate the correlation of solar term peak with onset and death of acute ischemic stroke. DESIGN: Retrospective case analysis. SETTINGS: Emergency Department of Foshan Municipal Hospital of Traditional Chinese Medicine; Department of Science and Education, the Second People's Hospital of Foshan. PARTICIPANTS: A total of 1 597 patients with acute ischemic stroke were selected from Emergency Room, Department of Neurology, Foshan Municipal Hospital of Traditional Chinese Medicine from 1994 to 2002. There were 875 males and 722 females, and their ages ranged from 33 to 97 years. All cases met the diagnostic criteria of acute cerebral infarction modified by the Second National Cerebrovascular Disease Academic Meeting; meanwhile, they were diagnosed with CT/MRI test. Patients and their relatives provided the confirmed consent. METHODS: Solar term of onset was retrospectively analyzed in 1 597 patients with acute ischemic stroke; among them, solar term of death in 90 cases were analyzed by using circular statistical analysis to calculate peak phase of onset and death of acute ischemic stroke and investigate the correlation of solar term with onset and death of acute ischemic stroke. MAIN OUTCOME MEASURES: Onset and death time of patients with acute ischemic stroke. RESULTS: Solar term of onset in 1 597 patients, especially solar term of death in 90 patients, was not concentrated (P 〉 0.05), and specific peak phase was not found out. Acute ischemic stroke low attacked from vernal equinox to summer begins, but death caused by acute ischemic stroke high attacked from grain buds to autumn begins. CONCLUSION: Patients with acute ischemic stroke do not have specific solar term peak of onset and death. 展开更多
关键词 cerebral infarct INCIDENCE DEATH circular statistical analysis
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Statistical Characteristics and Mechanistic Analysis of Suddenly Reversed Tropical Cyclones over the Western North Pacific Ocean 被引量:1
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作者 LUO Xia FEI Jianfang +3 位作者 HUANG Xiaogang CHENG Xiaoping DING Juli HE Yiqiang 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2015年第4期565-576,共12页
Based on best track data of tropical cyclones(TCs) from the Japan Meteorological Agency, the characteristics of suddenly reversed TCs(SRTCs), which have turning angles usually approaching 180°, are statistica... Based on best track data of tropical cyclones(TCs) from the Japan Meteorological Agency, the characteristics of suddenly reversed TCs(SRTCs), which have turning angles usually approaching 180°, are statistically analyzed from 1949 to 2011 over the western North Pacific Ocean. The typical large-scale circulation patterns of SRTCs are investigated using reanalysis data and dynamical composite analysis. Results show that turnings mainly occur in low latitudes between 10°N and 20°N,and mainly west of 135°E. The majority of SRTCs reach their peak intensity at, or slightly before, the turning time and subsequently decrease at some variable rate. Specifically, SRTCs are divided into four types, each containing two groups(i.e.eight groups in total) in terms of the moving-direction changes. The moving speed of all SRTC types except the south–north type decreases to its lowest during the 24 h, corresponding to a significant reduction in the primary steering components.According to the analysis of the 13 typical flow patterns found in this study, we suggest that sudden track changes are caused by the reversal steering flow. The original balance of the background flow patterns are broken up by new systems, e.g. binary TCs or dispersion-induced anticyclones. Additionally, sudden track changes are often due to double ridge variations of the subtropical high or weakened/strengthened high pressure in the east and west, respectively. 展开更多
关键词 tropical cyclone suddenly reversed turning statistical analysis steering flow
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A Statistical Analysis of China's Traffic Tunnel Development Data 被引量:12
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作者 Yong Zhao Pengfei Li 《Engineering》 2018年第1期3-5,共3页
关键词 A statistical analysis China's TRAFFIC TUNNEL DEVELOPMENT DATA
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STATISTICAL ANALYSIS ON THE INFLUENCE OF THE LANDFALLING STRONG TROPICAL CYCLONES IN THE CATASTROPHIC MIGRATIONS OF NILAPARVATA LUGENS(STL) IN CHINA 被引量:3
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作者 包云轩 丁文文 +2 位作者 谢晓金 兰平 陆明红 《Journal of Tropical Meteorology》 SCIE 2014年第1期8-16,共9页
In order to clarify the statistical pattern by which landfalling strong tropical cyclones(LSTCs)influenced the catastrophic migrations of rice brown planthopper(BPH),Nilaparvata lugens(stl)in China,the data of the L... In order to clarify the statistical pattern by which landfalling strong tropical cyclones(LSTCs)influenced the catastrophic migrations of rice brown planthopper(BPH),Nilaparvata lugens(stl)in China,the data of the LSTCs in China and the lighting catches of BPH that covered the main Chinese rice-growing regions from 1979 to 2008 were collected and analyzed in this work with the assistance of ArcGIS9.3,a software of geographic information system.The results were as follows:(1)In China,there were 220 strong tropical cyclones that passed the main rice-growing regions and 466 great events of BPH’s immigration in the 30 years from 1979 to 2008.73 of them resulted in the occurrence of BPH’s catastrphic migration(CM)events directly and 147 of them produced indirect effect on the migrations.(2)The number of the LSTCs was variable in different years during 1979 to 2008 and their influence was not the same in the BPH’s northward and southward migrations in the years.In the 30 years,the LSTCs brought more obvious influence on the migrations in 1980,1981,2005,2006 and 2007.The influence was the most obvious in2007 and all of the 7 LSTCs produced remarkable impact on the CMs of BPH’s populations.The effect of the LSTCs on the northward immigration of BPH’s populations was the most serious in 2006 and the influence on the southward immigration was the most remarkable in 2005.(3)In these years,the most of LSTCs occurred in July,August and September and great events of BPH's immigration occurred most frequently in the same months.The LSTCs played a more important role on the CM of BPH’s populations in the three months than in other months.(4)The analysis on the spatial distribution of the LSTCs and BPH’s immigration events for the different provinces showed that the BPH’s migrations in the main rice-growing regions of the Southeastern China were influenced by the LSTCs and the impact was different with the change of their spatial probability distribution during their passages.The most serious influence of the LSTCs on the BPH’s migrations occurred in Guangdong and Fujian provinces.(5)The statistical results indicated that a suitable insect source is an indispensable condition of the CMs of BPH when a LSTC influenced a rice-growing region. 展开更多
关键词 Nilaparvata lugens(stal) catastrphic immigration landfalling strong tropical cyclone statistical characteristics spatial analysis
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Potential hydraulic connectivity of coal mine aquifers based on statistical analysis of hydrogeochemistry 被引量:1
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作者 Xiang Zhao Wei-hua Peng +2 位作者 Kai Chen Xin-yi Qiu Lin-hua Sun 《Water Science and Engineering》 EI CAS CSCD 2022年第4期285-293,共9页
Mining activities interfere with the natural groundwater chemical environment,which may lead to hydrogeochemical changes of aquifers and mine water inrush disasters.This study analyzed the hydrochemical compositions o... Mining activities interfere with the natural groundwater chemical environment,which may lead to hydrogeochemical changes of aquifers and mine water inrush disasters.This study analyzed the hydrochemical compositions of 80 water samples in three aquifers and developed a water source identification model to explore the control factors and potential hydraulic connection of groundwater chemistry in a coal mine.The results showed that the hydrochemical types of the three aquifers were different.The main hydrochemical compositions of the loose-layer,coal-bearing,and limestone aquifers were HCO_(3)·Cl-Na,SO_(4)·HCO_(3)-Na,and SO_(4)-Na·Ca,respectively.The correlation,Unmix,and factor an-alyses showed that the hydrochemical composition of groundwater was controlled by the dissolution of soluble minerals(such as calcite,dolomite,gypsum,and halite)and the weathering of silicate minerals.The factor score plot combined with Q-mode cluster analysis demon-strated no remarkable hydraulic connection among the three aquifers in the study area.The water source identification model effectively identified the source of inrush water.Moreover,the mixing ratio model rationally quantified the contributions of the three aquifers to inrush water. 展开更多
关键词 GROUNDWATER Water chemistry Factor analysis Hydraulic connection Mathematical statistics
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