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Practice patterns among ophthalmic surgeons in treating concomitant oculoplastic conditions in preoperative period:A questionnaire-based study
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作者 Bijnya Birajita Panda Chitaranjan Mishra +3 位作者 Bhagabat Nayak Avik Kumar Roy Logesh Balakrishnan Priyadarshini Mishra 《World Journal of Clinical Cases》 SCIE 2025年第1期29-37,共9页
BACKGROUND Addressing oculoplastic conditions in the preoperative period ensures both the safety and functional success of any ophthalmic procedure.Some oculoplastic conditions,like nasolacrimal duct obstruction,have ... BACKGROUND Addressing oculoplastic conditions in the preoperative period ensures both the safety and functional success of any ophthalmic procedure.Some oculoplastic conditions,like nasolacrimal duct obstruction,have been extensively studied,whereas others,like eyelid malposition and thyroid eye disease,have received minimal or no research.AIM To investigate the current practice patterns among ophthalmologists while treating concomitant oculoplastic conditions before any subspecialty ophthalmic intervention.METHODS A cross-sectional survey was disseminated among ophthalmologists all over India.The survey included questions related to pre-operative evaluation,anaesthetic and surgical techniques preferred,post-operative care,the use of adjunctive therapies,and patient follow-up patterns.RESULTS A total of 180 ophthalmologists responded to the survey.Most practitioners(89%)felt that the ROPLAS test was sufficient during pre-operative evaluation before any subspecialty surgery was advised.The most common surgical techniques employed were lacrimal drainage procedures(Dacryocystorhinostomy)(63.3%),eyelid malposition repair(36.9%),and ptosis repair(58.7%).Post-operatively,47.7%of respondents emphasized that at least a 4-week gap should be maintained after lacrimal drainage procedures and eyelid surgeries.Sixty-seven percent of ophthalmologists felt that topical anaesthetic procedures should be preferred while performing ocular surgeries in thyroid eye disease patients.CONCLUSION Approximately 50%of ophthalmologists handle prevalent oculoplastic issues themselves,seeking the expertise of an oculoplastic surgeon under particular conditions.Many ophthalmologists still favor using ROPLAS as a preliminary screening method before proceeding with cataract surgery.Eyelid conditions and thyroid eye disease are not as commonly addressed before subspecialty procedures compared to issues like nasolacrimal duct obstruction and periocular infections. 展开更多
关键词 Oculoplasty Ophthalmic plastic surgery Nasolacrimal duct obstruction Practice patterns SURVEY
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On Relations for Moments of Generalized Order Statistics for Lindley–Weibull Distribution
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作者 Faten A.Momen khan Saman Hanif Shahbaz Muhammad Qaiser Shahbaz 《Computer Systems Science & Engineering》 SCIE EI 2022年第4期197-208,共12页
Moments of generalized order statistics appear in several areas of science and engineering.These moments are useful in studying properties of the random variables which are arranged in increasing order of importance,f... Moments of generalized order statistics appear in several areas of science and engineering.These moments are useful in studying properties of the random variables which are arranged in increasing order of importance,for example,time to failure of a computer system.The computation of these moments is sometimes very tedious and hence some algorithms are required.One algorithm is to use a recursive method of computation of these moments and is very useful as it provides the basis to compute higher moments of generalized order statistics from the corresponding lower-order moments.Generalized order statistics pro-vides several models of ordered data as a special case.The moments of general-ized order statistics also provide moments of order statistics and record values as a special case.In this research,the recurrence relations for single,product,inverse and ratio moments of generalized order statistics will be obtained for Lindley–Weibull distribution.These relations will be helpful for obtained moments of gen-eralized order statistics from Lindley–Weibull distribution recursively.Special cases of the recurrence relations will also be obtained.Some characterizations of the distribution will also be obtained by using moments of generalized order statistics.These relations for moments and characterizations can be used in differ-ent areas of computer sciences where data is arranged in increasing order. 展开更多
关键词 Generalized order statistics Lindley–Weibull distribution recurrence relations MOMENTS
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Randomly Weighted Averages on Order Statistics
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作者 Homei Hajir Hasanzadeh Leila Mina Ghasemi 《Applied Mathematics》 2013年第9期1340-1346,共7页
We study a well-known problem concerning a random variable uniformly distributed between two independent random variables. Two different extensions, randomly weighted average on independent random variables and random... We study a well-known problem concerning a random variable uniformly distributed between two independent random variables. Two different extensions, randomly weighted average on independent random variables and randomly weighted average on order statistics, have been introduced for this problem. For the second method, two-sided power random variables have been defined. By using classic method and power technical method, we study some properties for these random variables. 展开更多
关键词 Two-Sided POWER MOMENT WEIGHTED AVERAGES POWER DISTRIBUTION
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On Moment Generating Function of Generalized Order Statistics from Erlang-Truncated Exponential Distribution
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作者 Anamika Kulshrestha R. U. Khan Devendra Kumar 《Open Journal of Statistics》 2012年第5期557-564,共8页
In this paper explicit expressions and some recurrence relations are derived for marginal and joint moment generating functions of generalized order statistics from Erlang-truncated exponential distribution. The resul... In this paper explicit expressions and some recurrence relations are derived for marginal and joint moment generating functions of generalized order statistics from Erlang-truncated exponential distribution. The results for k-th record values and order statistics are deduced from the relations derived. Further, a characterizing result of this distribution on using the conditional expectation of function of generalized order statistics is discussed. 展开更多
关键词 Generalized Order STATISTICS Order STATISTICS Record Values Erlang-Truncated Exponential Distribution MARGINAL and Joint MOMENT Generating Function RECURRENCE Relations and Characterization
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Access block and prolonged length of stay in the emergency department are associated with a higher patient mortality rate 被引量:1
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作者 Ting Cheng Qian Peng +6 位作者 Ya-qing Jin Hong-jie Yu Pei-song Zhong Wei-min Gu Xiao-shan Wang Yi-ming Lu Li Luo 《World Journal of Emergency Medicine》 SCIE CAS CSCD 2022年第1期59-64,共6页
Access block,known as exit block or boarding,is defined as a situation in which patients who are admitted or planned for admission remain in the emergency department(ED)as they are unable to be transferred to an inpat... Access block,known as exit block or boarding,is defined as a situation in which patients who are admitted or planned for admission remain in the emergency department(ED)as they are unable to be transferred to an inpatient unit within a reasonable time frame(no longer than 8 hours).[1,2]Access block often occurs due to insufficient hospital capacity and is a major issue in emergency medicine.[3] 展开更多
关键词 ACCESS admitted TRANSFERRED
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Characterization of Negative Exponential Distribution Through Expectation of Function of Order Statistics
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作者 Bhatt Milind. B 《Journal of Statistical Science and Application》 2014年第2期79-84,共6页
For characterization of negative exponential distribution one needs any arbitrary non constant function only in place of approaches such as identical distributions, absolute continuity, constancy of regression of orde... For characterization of negative exponential distribution one needs any arbitrary non constant function only in place of approaches such as identical distributions, absolute continuity, constancy of regression of order statistics, continuity and linear regression of order statistics, non-degeneracy etc. available in the literature. Recently Bhatt characterized negative exponential distribution through expectation of non constant function of random variable. Attempt is made to extend the characterization of negative exponential distribution through expectation of any arbitrary non constant function of order statistics. 展开更多
关键词 统计学 统计方法 统计调查 应用
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Characterization of Pareto Distribution Through Expectation of Function of Order Statistics
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作者 Bhatt Milind. B 《Journal of Statistical Science and Application》 2016年第4期196-203,共8页
For characterization of Pareto distribution one needs any arbitrary non constant function only by approach of identity of distribution and equality of expectation of function of random variable in place of approaches ... For characterization of Pareto distribution one needs any arbitrary non constant function only by approach of identity of distribution and equality of expectation of function of random variable in place of approaches such as relation (linear) in (economic variation) reported and true income, independency of suitable function of order statistics, mean and the extreme observation of the sample etc. Examples are given for illustrative purpose 展开更多
关键词 CHARACTERIZATION Pareto distribution
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A Study on Mixture of Exponentiated Rayleigh and Exponentiated Exponential Distributions Based on Order Statistics
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作者 Rana Ali Mubarak Bakoban 《Journal of Mathematics and System Science》 2012年第3期163-170,共8页
Mixtures of lifetime distributions occur when two different causes of failure arc present, each with the same parametric form of lifetime distributions. This paper is considered with the mixture model of exponentiated... Mixtures of lifetime distributions occur when two different causes of failure arc present, each with the same parametric form of lifetime distributions. This paper is considered with the mixture model of exponentiated Rayleigh and exponentiated exponential distributions. The author's objectives are finding the statistical properties of the model and estimating the parameters of the model by using point estimation and interval estimation methods. First, some properties of the model with some graphs of the density function are discussed. Next, the maximum likelihood method of estimation is used for estimating scale and shape parameters of the model. Estimating the parameters is studied under complete and type II censored samples for different sample sizes. Asymptotic Fisher information matrix of the estimators for complete samples is founded with different sample sizes. The asymptotic variances of the maximum likelihood estimates are derived. Based on the asymptotic variances of the maximum likelihood estimates, interval estimates of the parameters are obtained. Some of the equations in this paper are solved by using numerical iteration such as Newton Raphson method by using Mathematica 7.0. The performance of findings in the paper is showed by demonstrating some numerical illustrations through Monte Carlo simulation study based on absolute relative bias and mean square error. 展开更多
关键词 Exponentiated Rayleigh distribution exponentiated exponential order statistics type-II censoring maximum likelihoodestimator Fisher information matrix.
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A Survey of Non-Monetary Institutional Infrastructural Support of Academic Anesthesia Departments in the United States
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作者 Steven H. Ginsberg Jonathan Kraidin +2 位作者 Christopher Gallagher Donald Hoover Al Solina 《Open Journal of Anesthesiology》 2013年第5期283-287,共5页
Financial pressure of multifactorial etiology promises to create new obstacles for academic anesthesia departments. Integrating the priorities of the academic and clinical mission of the anesthesia department, the med... Financial pressure of multifactorial etiology promises to create new obstacles for academic anesthesia departments. Integrating the priorities of the academic and clinical mission of the anesthesia department, the medical school, and the university hospital will require that anesthesia departments operate with maximal operational efficiency. Maintenance or expansion of institutional infrastructural support of the university anesthesia department will be necessary to achieve operational efficiencies, and to ensure that the safety of our patients is in no way compromised by financial concerns. Previous studies have documented increasing need for monetary institutional supports of academic anesthesia departments [1]. The purpose of this study is to delineate non-monetary institutional support afforded to academic anesthesia departments by their University Hospitals. After IRB approval, we electronically solicited the response to a 63 question survey (43 of which were used for the present study) from all 133 chairpersons of academic anesthesia departments in the United States. The remaining 20 questions were unrelated to the topics presented in this manuscript. 62 responded electronically, for an overall response rate of 46.6%. This study establishes the current state of infrastructural support afforded to academic anesthesia departments in the United States. 展开更多
关键词 Non MONETARY SUPPORT Infrastructural SUPPORT ANESTHESIA Sites
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Evaluation of Predictors of Suicidal Re-Attempt in Pediatric Patients in the Emergency Department
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作者 Ali Kemal Erenler Turker Yardan +1 位作者 Fuat Kulaksiz Cem Kocak 《Open Journal of Pediatrics》 2017年第4期309-319,共11页
Background: Suicidal attempt in children is a serious public health problem. A proper identification of features of suicide-related behavior may help physicians to develop an accurate approach. The aim of this study w... Background: Suicidal attempt in children is a serious public health problem. A proper identification of features of suicide-related behavior may help physicians to develop an accurate approach. The aim of this study was to clarify the characteristics of children with poisoning due to suicidal attempt and to determine the risk factors of suicidal re-attempt in the Emergency Department (ED) via a simple questionnaire. Methods: We collected medical data of patients under 18 years who were admitted to our ED with intoxication due to suicidal attempt, retrospectively. General characteristics of patients were evaluated. Patients were divided into 2 groups as 1) High risk: patients with repetitive suicide attempt;2) Low risk: patients with first time suicidal attempt. Results: A total of 57 patients were included in this study. The mean age was 15.91 ± 0.97. Majority of the patients were female (73.7%). Analgesics were the most frequent abused drugs with a ratio of 51.1%. It is determined that the most important variables affecting the risk of suicidal re-attempt are “idea about the suicide” and “purpose”. It was determined that patients with an idea of repetitive suicide (I will try again) and whose purpose was to die (I wish I have died) were in the most risky group with a history of previous suicidal attempt. Conclusion: This study suggests that answers of the pediatric patients to some question have a potential to predict the high risk patients. The risk of suicidal re-attempt may be predicted by the answers given to these questions: 1) What is your idea about suicide? 2) What was your purpose? 展开更多
关键词 SUICIDE Pediatric Patients Emergency Department
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Recent trends in the epidemiology and clinical outcomes of inflammatory bowel disease in South Korea,2010-2018 被引量:1
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作者 Seulji Kim Hyun Jung Lee +6 位作者 Seung Woo Lee Sanghyun Park Seong-Joon Koh Jong Pil Im Byeong Gwan Kim Kyung-Do Han Joo Sung Kim 《World Journal of Gastroenterology》 SCIE CAS 2024年第9期1154-1163,共10页
BACKGROUND Inflammatory bowel disease(IBD)was previously regarded as a Western disease;however,its incidence is increasing in the East.The epidemiology of IBD in Asia differs significantly from the patterns in the Wes... BACKGROUND Inflammatory bowel disease(IBD)was previously regarded as a Western disease;however,its incidence is increasing in the East.The epidemiology of IBD in Asia differs significantly from the patterns in the West.AIM To comprehensively investigate the epidemiology of IBD in South Korea,inclu-ding its incidence,prevalence,medication trends,and outcomes.METHODS We analyzed claims data from the Health Insurance Review and Assessment Service and Rare and Intractable Diseases(RIDs),operated by the National Health Insurance Service of South Korea.Patients with IBD were identified based on the International Classification of Diseases,Tenth Revision,and RID diagnostic codes for Crohn’s disease(CD)and ulcerative colitis(UC)from 2010 to 2018.RESULTS In total,14498 and 31409 patients were newly diagnosed with CD and UC,respectively,between 2010 and 2018.The annual average incidence of CD was 3.11 cases per 105 person-years,and that of UC was 6.74 cases per 10^(5) person-years.Since 2014,the incidence rate of CD has been stable,while that of UC has steadily increased,shifting the peak age group from 50-year-olds in 2010 to 20-year-olds in 2018.The CD and UC prevalence increased consistently over the study period;the use of 5-aminosali-cylates and corticosteroids gradually decreased,while that of immunomodulators and biologics steadily increased in both CD and UC.The clinical outcomes of IBD,such as hospitalization and surgery,decreased during the study period.CONCLUSION The CD incidence has been stable since 2014,but that of UC has increased with a shift to a younger age at peak incidence between 2010 and 2018.IBD clinical outcomes improved over time,with increased use of immunomodu-lators and biologics. 展开更多
关键词 Inflammatory bowel disease Crohn’s disease Ulcerative colitis INCIDENCE PREVALENCE
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Community detection on elite mathematicians’collaboration network
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作者 Yurui Huang Zimo Wang +1 位作者 Chaolin Tian Yifang Ma 《Journal of Data and Information Science》 CSCD 2024年第4期1-23,共23页
Purpose:This study focuses on understanding the collaboration relationships among mathematicians,particularly those esteemed as elites,to reveal the structures of their communities and evaluate their impact on the fie... Purpose:This study focuses on understanding the collaboration relationships among mathematicians,particularly those esteemed as elites,to reveal the structures of their communities and evaluate their impact on the field of mathematics.Design/methodology/approach:Two community detection algorithms,namely Greedy Modularity Maximization and Infomap,are utilized to examine collaboration patterns among mathematicians.We conduct a comparative analysis of mathematicians’centrality,emphasizing the influence of award-winning individuals in connecting network roles such as Betweenness,Closeness,and Harmonic centrality.Additionally,we investigate the distribution of elite mathematicians across communities and their relationships within different mathematical sub-fields.Findings:The study identifies the substantial influence exerted by award-winning mathematicians in connecting network roles.The elite distribution across the network is uneven,with a concentration within specific communities rather than being evenly dispersed.Secondly,the research identifies a positive correlation between distinct mathematical sub-fields and the communities,indicating collaborative tendencies among scientists engaged in related domains.Lastly,the study suggests that reduced research diversity within a community might lead to a higher concentration of elite scientists within that specific community.Research limitations:The study’s limitations include its narrow focus on mathematicians,which may limit the applicability of the findings to broader scientific fields.Issues with manually collected data affect the reliability of conclusions about collaborative networks.Practical implications:This study offers valuable insights into how elite mathematicians collaborate and how knowledge is disseminated within mathematical circles.Understanding these collaborative behaviors could aid in fostering better collaboration strategies among mathematicians and institutions,potentially enhancing scientific progress in mathematics.Originality/value:The study adds value to understanding collaborative dynamics within the realm of mathematics,offering a unique angle for further exploration and research. 展开更多
关键词 Greedy modularity maximization Infomap Collaboration network Community detection Mathematical awardees
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A unified Minorization-Maximization approach for estimation of general mixture models
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作者 HUANG Xi-fen LIU Deng-ge +1 位作者 ZHOU Yun-peng ZHU Fei 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2024年第2期343-362,共20页
The mixed distribution model is often used to extract information from heteroge-neous data and perform modeling analysis.When the density function of mixed distribution is complicated or the variable dimension is high... The mixed distribution model is often used to extract information from heteroge-neous data and perform modeling analysis.When the density function of mixed distribution is complicated or the variable dimension is high,it usually brings challenges to the parameter es-timation of the mixed distribution model.The application of MM algorithm can avoid complex expectation calculations,and can also solve the problem of high-dimensional optimization by decomposing the objective function.In this paper,MM algorithm is applied to the parameter estimation problem of mixed distribution model.The method of assembly and decomposition is used to construct the substitute function with separable parameters,which avoids the problems of complex expectation calculations and the inversion of high-dimensional matrices. 展开更多
关键词 MM algorithm mixed distribution model parameter estimation assembly decomposition tech-nology parameter separation
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THE LONG TIME BEHAVIOR OF THE FRACTIONAL ORNSTEIN-UHLENBECK PROCESS WITH LINEAR SELF-REPELLING DRIFT
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作者 夏晓宇 闫理坦 杨晴 《Acta Mathematica Scientia》 SCIE CSCD 2024年第2期671-685,共15页
Let B^(H) be a fractional Brownian motion with Hurst index 1/2≤H<1.In this paper,we consider the equation(called the Ornstein-Uhlenbeck process with a linear self-repelling drift)dX_(t)^(H)=dB_(t)^(H)+σ X_(t)^(H)... Let B^(H) be a fractional Brownian motion with Hurst index 1/2≤H<1.In this paper,we consider the equation(called the Ornstein-Uhlenbeck process with a linear self-repelling drift)dX_(t)^(H)=dB_(t)^(H)+σ X_(t)^(H)dt+vdt-θ(∫_(0)^(t)(X_(t)^(H)-X_(s)^(H))ds)dt,whereθ<0,σ,v∈ℝ.The process is an analogue of self-attracting diffusion(Cranston,Le Jan.Math Ann,1995,303:87–93).Our main aim is to study the large time behaviors of the process.We show that the solution X^(H)diverges to infinity as t tends to infinity,and obtain the speed at which the process X^(H)diverges to infinity. 展开更多
关键词 fractional Brownian motion stochastic difference equations rate of convergence ASYMPTOTIC
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BIG HANKEL OPERATORS ON HARDY SPACES OF STRONGLY PSEUDOCONVEX DOMAINS
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作者 陈伯勇 江良英 《Acta Mathematica Scientia》 SCIE CSCD 2024年第3期789-809,共21页
In this article,we investigate the(big) Hankel operator H_(f) on the Hardy spaces of bounded strongly pseudoconvex domains Ω in C^(n).We observe that H_(f ) is bounded on H~p(Ω)(1 <p <∞) if f belongs to BMO a... In this article,we investigate the(big) Hankel operator H_(f) on the Hardy spaces of bounded strongly pseudoconvex domains Ω in C^(n).We observe that H_(f ) is bounded on H~p(Ω)(1 <p <∞) if f belongs to BMO and we obtain some characterizations for Hf on H^(2)(Ω) of other pseudoconvex domains.In these arguments,Amar's L^(p)-estimations and Berndtsson's L^(2)-estimations for solutions of the ■_(b)-equation play a crucial role.In addition,we solve Gleason's problem for Hardy spaces H^(p)(Ω)(1 ≤p≤∞) of bounded strongly pseudoconvex domains. 展开更多
关键词 Hankel operator Hardy space Bergman space pseudoconvex domain
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Recurrent Neural Network Inspired Finite-Time Control Design
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作者 Jianan Liu Shihua Li Rongjie Liu 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第6期1527-1529,共3页
Dear Editor,This letter is concerned with the role of recurrent neural networks(RNNs)on the controller design for a class of nonlinear systems.Inspired by the architectures of RNNs,the system states are stacked accord... Dear Editor,This letter is concerned with the role of recurrent neural networks(RNNs)on the controller design for a class of nonlinear systems.Inspired by the architectures of RNNs,the system states are stacked according to the dynamic along with time while the controller is represented as the neural network output.To build the bridge between RNNs and finite-time controller,a novel activation function is imposed on RNNs to drive the convergence of states at finite-time and propel the overall control process smoother.Rigorous stability proof is briefly provided for the convergence of the proposed finite-time controller.At last,a numerical simulation example is presented to illustrate the efficiency of the proposed strategy.Neural networks can be classified as static(feedforward)and dynamic(recurrent)nets[1].The former nets do not perform well in dealing with training data and using any information of the local data structure[2].In contrast to the feedforward neural networks,RNNs are constituted by high dimensional hidden states with dynamics. 展开更多
关键词 DYNAMICS FINITE PROOF
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Computational Analysis of Novel Extended Lindley Progressively Censored Data
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作者 Refah Alotaibi Mazen Nassar Ahmed Elshahhat 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第3期2571-2596,共26页
A novel extended Lindley lifetime model that exhibits unimodal or decreasing density shapes as well as increasing,bathtub or unimodal-then-bathtub failure rates, named the Marshall-Olkin-Lindley (MOL) model is studied... A novel extended Lindley lifetime model that exhibits unimodal or decreasing density shapes as well as increasing,bathtub or unimodal-then-bathtub failure rates, named the Marshall-Olkin-Lindley (MOL) model is studied.In this research, using a progressive Type-II censored, various inferences of the MOL model parameters oflife are introduced. Utilizing the maximum likelihood method as a classical approach, the estimators of themodel parameters and various reliability measures are investigated. Against both symmetric and asymmetric lossfunctions, the Bayesian estimates are obtained using the Markov Chain Monte Carlo (MCMC) technique with theassumption of independent gamma priors. From the Fisher information data and the simulatedMarkovian chains,the approximate asymptotic interval and the highest posterior density interval, respectively, of each unknownparameter are calculated. Via an extensive simulated study, the usefulness of the various suggested strategies isassessedwith respect to some evaluationmetrics such as mean squared errors, mean relative absolute biases, averageconfidence lengths, and coverage percentages. Comparing the Bayesian estimations based on the asymmetric lossfunction to the traditional technique or the symmetric loss function-based Bayesian estimations, the analysisdemonstrates that asymmetric loss function-based Bayesian estimations are preferred. Finally, two data sets,representing vinyl chloride and repairable mechanical equipment items, have been investigated to support theapproaches proposed and show the superiority of the proposed model compared to the other fourteen lifetimemodels. 展开更多
关键词 Marshall-Olkin-Lindleymodel reliability inference Bayesian and classical inference progressive Type-II censoring
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Optimality of Group Testing with Differential Misclassification
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作者 LI Yiming ZHANG Hong LIU Aiyi 《应用概率统计》 CSCD 北大核心 2024年第4期644-662,共19页
Group testing is a method that can be used to estimate the prevalence of rare infectious diseases,which can effectively save time and reduce costs compared to the method of random sampling.However,previous literature ... Group testing is a method that can be used to estimate the prevalence of rare infectious diseases,which can effectively save time and reduce costs compared to the method of random sampling.However,previous literature only demonstrated the optimality of group testing strategy while estimating prevalence under some strong assumptions.This article weakens the assumption of misclassification rate in the previous literature,considers the misclassification rate of the infected samples as a differentiable function of the pool size,and explores some optimal properties of group testing for estimating prevalence in the presence of differential misclassification conforming to this assumption.This article theoretically demonstrates that the group testing strategy performs better than the sample by sample procedure in estimating disease prevalence when the total number of sample pools is given or the size of the test population is determined.Numerical simulation experiments were conducted to evaluate the performance of group tests in estimating prevalence in the presence of dilution effect. 展开更多
关键词 group testing sensitivity SPECIFICITY dilution effect differential misclassification PREVALENCE
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Automated Machine Learning Algorithm Using Recurrent Neural Network to Perform Long-Term Time Series Forecasting
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作者 Ying Su Morgan C.Wang Shuai Liu 《Computers, Materials & Continua》 SCIE EI 2024年第3期3529-3549,共21页
Long-term time series forecasting stands as a crucial research domain within the realm of automated machine learning(AutoML).At present,forecasting,whether rooted in machine learning or statistical learning,typically ... Long-term time series forecasting stands as a crucial research domain within the realm of automated machine learning(AutoML).At present,forecasting,whether rooted in machine learning or statistical learning,typically relies on expert input and necessitates substantial manual involvement.This manual effort spans model development,feature engineering,hyper-parameter tuning,and the intricate construction of time series models.The complexity of these tasks renders complete automation unfeasible,as they inherently demand human intervention at multiple junctures.To surmount these challenges,this article proposes leveraging Long Short-Term Memory,which is the variant of Recurrent Neural Networks,harnessing memory cells and gating mechanisms to facilitate long-term time series prediction.However,forecasting accuracy by particular neural network and traditional models can degrade significantly,when addressing long-term time-series tasks.Therefore,our research demonstrates that this innovative approach outperforms the traditional Autoregressive Integrated Moving Average(ARIMA)method in forecasting long-term univariate time series.ARIMA is a high-quality and competitive model in time series prediction,and yet it requires significant preprocessing efforts.Using multiple accuracy metrics,we have evaluated both ARIMA and proposed method on the simulated time-series data and real data in both short and long term.Furthermore,our findings indicate its superiority over alternative network architectures,including Fully Connected Neural Networks,Convolutional Neural Networks,and Nonpooling Convolutional Neural Networks.Our AutoML approach enables non-professional to attain highly accurate and effective time series forecasting,and can be widely applied to various domains,particularly in business and finance. 展开更多
关键词 Automated machine learning autoregressive integrated moving average neural networks time series analysis
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Dynamics of Advantageous Mutant Spread in Spatial Death-Birth and Birth-Death Moran Models
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作者 Jasmine Foo Einar Bjarki Gunnarsson +1 位作者 Kevin Leder David Sivakoff 《Communications on Applied Mathematics and Computation》 EI 2024年第1期576-604,共29页
The spread of an advantageous mutation through a population is of fundamental interest in population genetics. While the classical Moran model is formulated for a well-mixed population, it has long been recognized tha... The spread of an advantageous mutation through a population is of fundamental interest in population genetics. While the classical Moran model is formulated for a well-mixed population, it has long been recognized that in real-world applications, the population usually has an explicit spatial structure which can significantly influence the dynamics. In the context of cancer initiation in epithelial tissue, several recent works have analyzed the dynamics of advantageous mutant spread on integer lattices, using the biased voter model from particle systems theory. In this spatial version of the Moran model, individuals first reproduce according to their fitness and then replace a neighboring individual. From a biological standpoint, the opposite dynamics, where individuals first die and are then replaced by a neighboring individual according to its fitness, are equally relevant. Here, we investigate this death-birth analogue of the biased voter model. We construct the process mathematically, derive the associated dual process, establish bounds on the survival probability of a single mutant, and prove that the process has an asymptotic shape. We also briefly discuss alternative birth-death and death-birth dynamics, depending on how the mutant fitness advantage affects the dynamics. We show that birth-death and death-birth formulations of the biased voter model are equivalent when fitness affects the former event of each update of the model, whereas the birth-death model is fundamentally different from the death-birth model when fitness affects the latter event. 展开更多
关键词 Spatial death-birth models Spatial birth-death models Spatial evolutionary models Spatial cancer models Evolutionary graph theory Stochastic processes Biased voter model Dual process Fixation probability Shape theorem
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