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Dynamical distribution of continuous service time model involving non-Maxwellian collision kernel and value functions
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作者 Minfang Zhao Lingting Kong +1 位作者 Miao Liu Shaoyong Lai 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第9期340-348,共9页
The distribution of continuous service time in call centers is investigated.A non-Maxwellian collision kernel combining two different value functions in the interaction rule are used to describe the evolution of conti... The distribution of continuous service time in call centers is investigated.A non-Maxwellian collision kernel combining two different value functions in the interaction rule are used to describe the evolution of continuous service time,respectively.Using the statistical mechanical and asymptotic limit methods,Fokker–Planck equations are derived from the corresponding Boltzmann-type equations with non-Maxwellian collision kernels.The steady-state solutions of the Fokker–Planck equation are obtained in exact form.Numerical experiments are provided to support our results under different parameters. 展开更多
关键词 kinetic theory service time Fokker-Planck equation value function
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Three Dimensions of Cultivating New Generations: Value Implication, Scientific Connotation, and Cultivation Path
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作者 Yihan Zhang Yuhang Fang 《Journal of Contemporary Educational Research》 2024年第6期255-260,共6页
The new generation of the times is the latest requirement for young people in the new era,and it is the latest training goal for young people put forward by the Party and the country in the face of the second centenni... The new generation of the times is the latest requirement for young people in the new era,and it is the latest training goal for young people put forward by the Party and the country in the face of the second centennial goal.At the 19th National Congress,it was put forward by the country that the concept of“new generation of the times”for the first time,indicating the training direction and theoretical guidance for the new generation of the times.The new age requires young people to have firm ideals and beliefs,excellent skills,and a great spirit of responsibility.The proposition of cultivating a new generation of the times is a deep exploration and summary of Marx’s theory of“all-round human development,”Lenin’s youth view and the education view of excellent traditional Chinese culture,and the proposition needs to strengthen the leadership of the Party,give play to the leading role of socialist core values,and the youth themselves should actively act to realize the transformation of theoretical and practical results. 展开更多
关键词 New generation of the times value implication scientific connotation Cultivation path
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A Novel Inverse-Free Neurodynamic Approach for Solving Absolute Value Equations
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作者 Tao Li 《Journal of Applied Mathematics and Physics》 2024年第10期3458-3468,共11页
We propose a novel inverse-free neurodynamic approach (NIFNA) for solving absolute value equations (AVE). The NIFNA guarantees global convergence and notably improves convergence speed by achieving fixed-time converge... We propose a novel inverse-free neurodynamic approach (NIFNA) for solving absolute value equations (AVE). The NIFNA guarantees global convergence and notably improves convergence speed by achieving fixed-time convergence. To validate the theoretical findings, numerical simulations are conducted, demonstrating the effectiveness and efficiency of the proposed NIFNA. 展开更多
关键词 Absolute value Equations Neurodynamic Approach Fixed-time Convergence Numerical simulations
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Boundary Value Problems of p-Laplace Equations with Finite Time Delay
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作者 王宏洲 邓立虎 葛渭高 《Journal of Beijing Institute of Technology》 EI CAS 2001年第1期1-6,共6页
By establishing equivalent fixed point theorem, the boundary value problems of p Laplace equations with finite time delay are studied. It’s the first time that the functional differential equation is discussed w... By establishing equivalent fixed point theorem, the boundary value problems of p Laplace equations with finite time delay are studied. It’s the first time that the functional differential equation is discussed with p Laplacian. The topological degree and fixed point theorem on cone are used to prove the existence of solution and positive solution. The conditions are all easy to check. 展开更多
关键词 boundary value problem n Laplacian finite time delay fixed point
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Storage time affects the level and diagnostic efficacy of plasma biomarkers for neurodegenerative diseases
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作者 Lifang Zhao Mingkai Zhang +4 位作者 Qimeng Li Xuemin Wang Jie Lu Ying Han Yanning Cai 《Neural Regeneration Research》 SCIE CAS 2025年第8期2373-2381,共9页
Several promising plasma biomarker proteins,such as amyloid-β(Aβ),tau,neurofilament light chain,and glial fibrillary acidic protein,are widely used for the diagnosis of neurodegenerative diseases.However,little is k... Several promising plasma biomarker proteins,such as amyloid-β(Aβ),tau,neurofilament light chain,and glial fibrillary acidic protein,are widely used for the diagnosis of neurodegenerative diseases.However,little is known about the long-term stability of these biomarker proteins in plasma samples stored at-80°C.We aimed to explore how storage time would affect the diagnostic accuracy of these biomarkers using a large cohort.Plasma samples from 229 cognitively unimpaired individuals,encompassing healthy controls and those experiencing subjective cognitive decline,as well as 99 patients with cognitive impairment,comprising those with mild cognitive impairment and dementia,were acquired from the Sino Longitudinal Study on Cognitive Decline project.These samples were stored at-80°C for up to 6 years before being used in this study.Our results showed that plasma levels of Aβ42,Aβ40,neurofilament light chain,and glial fibrillary acidic protein were not significantly correlated with sample storage time.However,the level of total tau showed a negative correlation with sample storage time.Notably,in individuals without cognitive impairment,plasma levels of total protein and tau phosphorylated protein threonine 181(p-tau181)also showed a negative correlation with sample storage time.This was not observed in individuals with cognitive impairment.Consequently,we speculate that the diagnostic accuracy of plasma p-tau181 and the p-tau181 to total tau ratio may be influenced by sample storage time.Therefore,caution is advised when using these plasma biomarkers for the identification of neurodegenerative diseases,such as Alzheimer's disease.Furthermore,in cohort studies,it is important to consider the impact of storage time on the overall results. 展开更多
关键词 Alzheimer’s disease amyloid-β diagnostic ability glial fibrillary acidic protein NEURODEGENERATION neurofilament light chain plasma biomarkers single molecule array storage time tau
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The Time Value of Qu Qiubai's Creative Thinking
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作者 邓会君 《海外英语》 2014年第9X期195-196,共2页
Qu Qiubai is a Marxist,proletarian revolutionist,great thinker and theorist who was never afraid of conducting creative thinking.It is creative thinking that have helped Qu Qiubai to accurately feel the pulse of the t... Qu Qiubai is a Marxist,proletarian revolutionist,great thinker and theorist who was never afraid of conducting creative thinking.It is creative thinking that have helped Qu Qiubai to accurately feel the pulse of the times,to timely respond to the requirement of the times and to scientifically answer the realist question raised by times in carrying out the China’s revolutionary theory into practice.In a word,creative thinking gave full demonstration to Qu Qiu bai’s time value by following the general trend and requirements of history and keeping up with the times. 展开更多
关键词 QU Qiubai CREATIVE THINKING time value
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Pearl S. Buck’s Values of “Cultural Convergence” and Their Application
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作者 WANG Yan ZHU Ze-yuan SHI Hui-ge 《Cultural and Religious Studies》 2023年第1期9-18,共10页
The typical features of internal and external integration of cultures as revealed by the conception of“cultural convergence”provide a new perspective on the study of cultural exchanges and mutual learning.In the con... The typical features of internal and external integration of cultures as revealed by the conception of“cultural convergence”provide a new perspective on the study of cultural exchanges and mutual learning.In the context of“a global community of shared future for humankind”,this paper adopts the novel idea of“cultural convergence”to probe the growth of Pearl S.Buck’s cultural values and the specific contents and representation of Pearl S.Buck’s conception of“cultural convergence”,highlighting the application of Pearl S.Buck’s values to cultural education,growth and success,family education,cultural exchanges,humanistic practices,etc.Feasible suggestions and countermeasures are put forward to better promote the cultural exchanges and mutual learning as well as the convergence of different cultures. 展开更多
关键词 Pearl s.Buck values of“cultural convergence” applied research
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Emotional Value Care to Promote Emotional Communication Between Teachers and Students Under the New Era of Education Mode
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作者 Yongdong Xiao 《Journal of Contemporary Educational Research》 2023年第1期7-12,共6页
With the development of the times and the progress of the society,the ancient education mode can no longer meet the requirements of the times.The concept of educating people must keep pace with the times.The way teach... With the development of the times and the progress of the society,the ancient education mode can no longer meet the requirements of the times.The concept of educating people must keep pace with the times.The way teachers and students get along is no longer like in ancient times,where teachers teach students to listen.In the new era,it is necessary to build a new model of interaction between teachers and students.If educators pay attention and come to understand students’psychology,listen to students’aspirations,tend to students’emotions,grow in love for education,and treat students from their hearts,they would be able to win the favor of students.Paying attention to students’emotional value can promote emotional communication between teachers and students.It is possible to adapt to the requirements of the new era for the construction of morality and ethics among teachers by caring for students’emotional value. 展开更多
关键词 Teacher’s morality Teacher’s style Emotional value Emotional communication
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Prognostic Value of Semi-Quantitative 18F-FDG PET/CT Parameters in Hodgkin’s Lymphoma
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作者 Yong Zhou Congyang Hu +7 位作者 Yue Li Xiting Xia Jun Lei Jingyi Chen Hua Xu Mei He Hongyun Jian Shuping You 《Proceedings of Anticancer Research》 2023年第6期108-115,共8页
Objective:To assess the prognostic value of maximum standardized uptake value(SUVmax),metabolic tumor volume(MTV),and total lesion glycolysis(TLG)determined by 18F-fluorodeoxyglucose positron emission tomography-compu... Objective:To assess the prognostic value of maximum standardized uptake value(SUVmax),metabolic tumor volume(MTV),and total lesion glycolysis(TLG)determined by 18F-fluorodeoxyglucose positron emission tomography-computed tomography(18F-FDG PET/CT)imaging in Hodgkin’s lymphoma patients.Methods:A total of 148 Hodgkin’s lymphoma patients diagnosed with lymph node biopsy from October 2014 to October 2015 were retrospectively analyzed followed by categorizing into good(125 cases)and poor(23 cases)prognosis groups.The chi-squared test was used to analyze the clinicopathological characteristics of Hodgkin’s lymphoma patients with the semi-quantitative 18F-FDG PET/CT parameters;the Spearman method was used to analyze the correlation between the semi-quantitative parameters and clinicopathological features of Hodgkin’s lymphoma;receiver operating characteristic curve was used to analyze the predictive value of the semi-quantitative parameters for poor prognosis of Hodgkin’s lymphoma patients.Results:Mean SUVmax,MTV,and TLG of the 148 cases of Hodgkin’s lymphoma were 7.26±2.38,12.46±3.14 cm3,and 76.83±18.56 g,respectively.Significant variations in the Ann Arbor stage and clinical classification were observed with different levels of semi-quantitative parameters(P<0.05).The semi-quantitative parameters were not correlated with age and gender(P>0.05)but positively correlated with Ann Arbor stage and clinical classification(P<0.05).These parameters in the poor prognosis group were higher than those in the good prognosis group(P<0.05).The area under the curve(AUC)of SUVmax,MTV,and TLG in predicting the poor prognosis group was 0.881,0.875,and 0.838,with cut-off values of 7.264,12.898 cm3,and 74.580g,as well as specificity of 88.8%,84.0%,and 78.4%,and sensitivity of 87.0%,87.0%,and 78.3%,respectively;the AUC of the combined prediction was 0.986,with a specificity of 97.6%and sensitivity of 86.3%.Conclusion:The semi-quantitative 18F-FDG PET/CT parameters provide valuable insights for Hodgkin’s lymphoma prognosis assessment. 展开更多
关键词 Hodgkin’s lymphoma 18F-fluorodeoxyglucose positron emission tomography-computed tomography Maximum standardized uptake value Metabolic tumor volume Total lesion glycolysis PROGNOsIs
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Comparison of pH Value, TBA Value, Glycogen and Lactic Acid Content in Muscle of Landrace and Yorkshire under Different Storage Time and Conditions 被引量:2
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作者 Zhang Yin Guo Jianfeng +3 位作者 Lin Haichao Wang Jiying Wang Cheng Wu Ying 《Animal Husbandry and Feed Science》 CAS 2017年第3期145-150,164,共7页
In order to assess the meat quality under different storage time and conditions, the pH value, TBA value, glycogen and lactic acid content in muscle of Landrace and Yorkshire were measured. The results showed that wit... In order to assess the meat quality under different storage time and conditions, the pH value, TBA value, glycogen and lactic acid content in muscle of Landrace and Yorkshire were measured. The results showed that within 10 h post slaughtering, post slaughtering time had extremely significant influence on pH value and lactic acid content of Landrace, but had no significant influence on glycogen content and TBA value. On the other hand, post slaughtering time had extremely significant influence on pH value of Yorkshire, but had no significant influence on glycogen, lactic acid content and TBA value. The pH values of Yorkshire at 3, 5 and 10 h post slaughtering were 5.21% ( P 〈 0.01 ), 5.64% ( P 〈 0.05 ) and 5.59% ( P 〈 0.05 ) higher than those of Landrace, respectively ; the lactic acid content in muscle of Landrace at 10 h post slaughtering was 56.04% (P 〈0.05) higher than that of Yorkshire; the TBA value in muscle of Yorkshire at 10 h post slaughtering was 89. 19% (P 〈 0.01 ) higher than that of Landrace; there was no significant difference in glycogen content between Yorkshire and Landrace. When pork stored at 4℃, storage time had no significant influence on pH value and glycogen content in muscle of Landrace, but had significant influence on drip loss, lactic acid content and TBA value ; storage time had no significant influence on pH value, glycogen content and TBA value in muscle of Yorkshire, but extremely significant influence on drip loss and significant influence on lactic acid content. The pH value in muscle of Yorkshire at 24 h post storage at 4℃ was 6.56% (P 〈0.05) higher than that of Landrace; the glycogen contents in muscle of Landrace at 24, 48, 72, 96, 120 and 144 h post storage at 4℃ were 84.90% (P〈0.05),78.40% (P〈0.01), 101.87% (P〈0.05), 83.80% (P〈0.05), 83.59% (P〈 0.05)and67.25% (P〈0.01)higher than those of York-shire, respectively; the drip loss of Landrace at 72 h post storage and TBA value at 144 h post storage were 55.70% ( P 〈 0.05 ) and 141.33 % ( P 〈 0.01 ) higher than those of Yorkshire, respectively; there was no significant difference in glycogen content between Yorkshire and Landrace. When pork stored at -20℃, storage time had significant influence on TBA value in muscle of Landrace, but had no significant influence on pH value, thawing water loss rate, glycogen and lactic acid content; storage time had no significant impact on pH value, thawing water loss rate, glycogen content and TBA value in muscle of Yorkshire, and had significant influence on lactic acid content. The pH value in muscle of Yorkshire at 24 h post storage at - 20℃ was 5.43 % ( P 〈 0.05 ) higher than that of I.andrace ; the glycogen contents in muscle of Landrace at 24, 48, 72, 96, 120 h post storage at - 20℃ were 85.08% ( P 〈0. 05 ), 108.66% ( P 〈 0.01 ), 72.69% ( P 〈 0.05 ), 90.31% ( P 〈 0.01 ), 70.38% ( P 〉 0.05 ) higher than those of Yorkshire, respectively ; the thawing water loss rates of Landrace at 24 and 72 h were 160.14% ( P 〈 0.05 ) and 74.32% ( P 〈 0.05 ) higher than those of Yorkshire, respectively ; there was no significant difference in lactic acid content and TBA value at the same time point between Yorkshire and Landrace. 展开更多
关键词 PORK storage time and conditions pH value GLYCOGEN Lactic acid content TBA value
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Existence of Positive Solutions for Higher Order Boundary Value Problem on Time Scales 被引量:2
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作者 Xie Da-peng Liu Yang +1 位作者 Sun Ming-zhe Li Yong 《Communications in Mathematical Research》 CSCD 2013年第1期1-13,共13页
In this paper, we investigate the existence of positive solutions of a class higher order boundary value problems on time scales. The class of boundary value problems educes a four-point (or three-point or two-point... In this paper, we investigate the existence of positive solutions of a class higher order boundary value problems on time scales. The class of boundary value problems educes a four-point (or three-point or two-point) boundary value problems, for which some similar results are established. Our approach relies on the Krasnosel'skii fixed point theorem. The result of this paper is new and extends previously known results. 展开更多
关键词 higher order boundary value problem positive solution sEMIPOsITONE on time scale fixed point
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Influence of Initial Value of Transient Time Step on Numerical Simulation of Blow Molding Balloon 被引量:3
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作者 Jinyao Bian Guobao Jin +1 位作者 Peng Qin Guanghui Dai 《American Journal of Computational Mathematics》 2020年第2期266-274,共9页
The correlation between the initial time value of transient iterative parameters and the blowing pressure in the numerical simulation process of blowing balloon is investigated by POLYFLOW. The results show that: 1) A... The correlation between the initial time value of transient iterative parameters and the blowing pressure in the numerical simulation process of blowing balloon is investigated by POLYFLOW. The results show that: 1) As the blow molding pressure increases, the boundary value of the iterative time step decreases rapidly at first and then slowly. At the end of the first step of iterative calculation for each boundary value, the balloon parison is in the mold core cavity. 2) If the initial time value of transient iterative parameters is smaller than the boundary value of the iterative time step, the balloon parison is still in the mold core cavity at the end of the first iteration. However, if the iterative calculation continues, the calculation process may be interrupted when the time step is smaller than the initial time value of the transient iterative parameters, which makes the blow molding simulation of balloon unable to continue. 3) It is suggested that the initial time value of transient iterative parameters is one order of magnitude smaller than the boundary value of the iterative time step to complete smoothly the simulation of blow molding balloon. 展开更多
关键词 Transient Iteration time-step Initial time value Balloon Forming Blow Molding Pressure
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Reconstruction of time series with missing value using 2D representation-based denoising autoencoder 被引量:1
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作者 TAO Huamin DENG Qiuqun XIAO Shanzhu 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2020年第6期1087-1096,共10页
Time series analysis is a key technology for medical diagnosis,weather forecasting and financial prediction systems.However,missing data frequently occur during data recording,posing a great challenge to data mining t... Time series analysis is a key technology for medical diagnosis,weather forecasting and financial prediction systems.However,missing data frequently occur during data recording,posing a great challenge to data mining tasks.In this study,we propose a novel time series data representation-based denoising autoencoder(DAE)for the reconstruction of missing values.Two data representation methods,namely,recurrence plot(RP)and Gramian angular field(GAF),are used to transform the raw time series to a 2D matrix for establishing the temporal correlations between different time intervals and extracting the structural patterns from the time series.Then an improved DAE is proposed to reconstruct the missing values from the 2D representation of time series.A comprehensive comparison is conducted amongst the different representations on standard datasets.Results show that the 2D representations have a lower reconstruction error than the raw time series,and the RP representation provides the best outcome.This work provides useful insights into the better reconstruction of missing values in time series analysis to considerably improve the reliability of timevarying system. 展开更多
关键词 time series missing value 2D representation denoising autoencoder(DAE) RECONsTRUCTION
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Values of the Times of Marx's Theory of Science and Technology Progress and Utilization of Natural Resources 被引量:1
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作者 Jiefang ZHU 《Meteorological and Environmental Research》 CAS 2020年第4期78-82,共5页
Marx's theory of scientific and technological progress and utilization of natural resources is an indispensable and important part of Marx's economic theory.To realize the harmonious unification of man and nat... Marx's theory of scientific and technological progress and utilization of natural resources is an indispensable and important part of Marx's economic theory.To realize the harmonious unification of man and nature,man must correctly understand the effect of scientific and technological progress on the use of natural resources,fundamentally solve the problem that scientific and technological progress cannot replace the position of natural resources in economic development,and objectively evaluate the relationship between human power and the power of nature.Grasping and comprehending the scientific connotation of Marx's theory of scientific and technological progress and utilization of natural resources has a very important theoretical value and practical significance for saving and effectively using natural resources and building an environment-friendly society. 展开更多
关键词 scientific and technological progress Utilization of natural resources values of the times
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Determining the time and space domains forestimating b value in seismic zoning
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作者 黄玮琼 李文香 《Acta Seismologica Sinica(English Edition)》 CSCD 1998年第5期3-8,共6页
To take the seismic zone that includes the great shock with M S8.5 as the statistical unit of estimating b value can often lead to more large variance, because the seismogenic zone of the great shock with M... To take the seismic zone that includes the great shock with M S8.5 as the statistical unit of estimating b value can often lead to more large variance, because the seismogenic zone of the great shock with M S8.5 are larger than that delineated in general seismic zone. Two-level statistical units are considered in this paper. The seismic province is the first level unit that is suitable for group of earthquakes including the great shock of M S8.5. A seismic province can be divided into several seismic zones. They can be taken as the second level unit for group of quakes in which the super magnitude of the greatest shock do not exceed 8. Because of the nonstationarity in time of seismic activity, the unbalancedness of data and differential of seismic temporal series feature in different areas need to be considered when we select the time period for estimating b value. According to local conditions, the time period is selected at one′s discretion in order to reflect seismicity level of this statistical unit in future 100 years. 展开更多
关键词 estimating b value statistical unit time period magnitude interval
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SOME RESULTSON LAG INCREMENTSOF PRINCIPAL VALUE OF BROWNIAN LOCAL TIME
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作者 Wen JiweiDept.ofMath.,ZhejiangUniv.(XixiCampus),Hangzhou310028,China 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2002年第2期199-207,共9页
Let W be a standard Brownian motion,and define Y(t) =∫t 0 ds W(s) as Cauchy' s principal value related to the local time of W.We study some limitresults on lag increments of Y(t) and obtain various results all... Let W be a standard Brownian motion,and define Y(t) =∫t 0 ds W(s) as Cauchy' s principal value related to the local time of W.We study some limitresults on lag increments of Y(t) and obtain various results all of which are related to earlier work by Hanson and Russo in 1 983 展开更多
关键词 lag increment principal value Brownian local time
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Existence of Multiple Positive Solutions for <i>n</i><sup>th</sup>Order Two-Point Boundary Value Problems on Time Scales
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作者 Kapula Rajendra Prasad Penugurthi Murali Nadakuduti V. V. S. Suryanarayana 《Advances in Pure Mathematics》 2013年第1期70-77,共8页
We consider the nth order nonlinear differential equation on time scales subject to the right focal type two-point boundary conditions We establish a criterion for the existence of at least one positive solution by ut... We consider the nth order nonlinear differential equation on time scales subject to the right focal type two-point boundary conditions We establish a criterion for the existence of at least one positive solution by utilizing Krasnosel’skii fixed point theorem. And then, we establish the existence of at least three positive solutions by utilizing Leggett-Williams fixed point theorem. 展开更多
关键词 time scale Dynamical Equation Positive solution CONE Boundary value Problem
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Estimation of Dynamic VaR in Chinese Stock Markets Based on Time Scale and Extreme Value Theory
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作者 林宇 黄登仕 +1 位作者 杨洁 魏宇 《Journal of Southwest Jiaotong University(English Edition)》 2008年第1期73-80,共8页
The accuracy and time scale invariance of value-at-risk (VaR) measurement methods for different stock indices and at different confidence levels are tested. Extreme value theory (EVT) is applied to model the extre... The accuracy and time scale invariance of value-at-risk (VaR) measurement methods for different stock indices and at different confidence levels are tested. Extreme value theory (EVT) is applied to model the extreme tail of standardized residual series of daily/weekly indices losses, and parametric and nonparametric methods are used to estimate parameters of the general Pareto distribution (GPD), and dynamic VaR for indices of three stock markets in China. The accuracy and time scale invariance of risk measurement methods through back-testing approach are also examined. Results show that not all the indices accept time scale invariance; there are some differences in accuracy between different indices at various confidence levels. The most powerful dynamic VaR estimation methods are EVT-GJR-Hill at 97.5% level for weekly loss to Shanghai stock market, and EVT-GARCH-MLE (Hill) at 99.0% level for weekly loss to Taiwan and Hong Kong stock markets, respectively. 展开更多
关键词 Chinese stock markets Dynamic VaR time scaling Extreme value theory Back-testing
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Well-posedness of the time-varying linear electromagnetic initial-boundary value proble
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作者 谢莉 雷银照 《Chinese Physics B》 SCIE EI CAS CSCD 2007年第9期2523-2536,共14页
The well-posedness of the initial-boundary value problem of the time-varying linear electromagnetic field in a multi-medium region is investigated. Function spaces are defined, with Faraday's law of electromagnetic i... The well-posedness of the initial-boundary value problem of the time-varying linear electromagnetic field in a multi-medium region is investigated. Function spaces are defined, with Faraday's law of electromagnetic induction and the initial-boundary conditions considered as constraints. Gauss's formula applied to a multi-medium region is used to derive the energy-estimating inequality. After converting the initial-boundary conditions into homogeneous ones and analysing the characteristics of an operator introduced according to the total current law, the existence, uniqueness and stability of the weak solution to the initial-boundary value problem of the time-varying linear electromagnetic field are proved. 展开更多
关键词 WELL-POsEDNEss initial-boundary value problem multi-medium region Maxwell's equations
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Continuous-Time and Discrete-Time Singular Value Decomposition of an Impulse Response Function
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作者 Rogelio Luck Yucheng Liu 《Applied Mathematics》 2021年第4期336-347,共12页
This paper proposes the continuous-time singular value decomposition (SVD) for the impulse response function, a special kind of Green’s functions, in order to find a set of singular functions and singular values so t... This paper proposes the continuous-time singular value decomposition (SVD) for the impulse response function, a special kind of Green’s functions, in order to find a set of singular functions and singular values so that the convolutions of such function with the set of singular functions on a specified domain are the solutions to the inhomogeneous differential equations for those singular functions. A numerical example was illustrated to verify the proposed method. Besides the continuous-time SVD, a discrete-time SVD is also presented for the impulse response function, which is modeled using a Toeplitz matrix in the discrete system. The proposed method has broad applications in signal processing, dynamic system analysis, acoustic analysis, thermal analysis, as well as macroeconomic modeling. 展开更多
关键词 singular value Decomposition Impulse Response Function Green’s Function Toeplitz Matrix Hankel Matrix
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