Focused on the non-statlonarity and real-time analysis of signal in flutter test with progression variable speed （FTPVS）, a new method of recursive time-frequency analysis is presented. The time-varying system is tr...Focused on the non-statlonarity and real-time analysis of signal in flutter test with progression variable speed （FTPVS）, a new method of recursive time-frequency analysis is presented. The time-varying system is tracked on-line by building a time-varying parameter model, and then the relevant parameter spectrum can be obtained. The feasibility and advantages of the method are examined by digital simulation. The results of FTPVS at low-speed wind-tunnel promise the engineering application perspective of the method.展开更多
The estimation of generalized exponential distribution based on progressive censoring with binomial removals is presented, where the number of units removed at each failure time follows a binomial distribution. Maximu...The estimation of generalized exponential distribution based on progressive censoring with binomial removals is presented, where the number of units removed at each failure time follows a binomial distribution. Maximum likelihood estimators of the parameters and their confidence intervals are derived. The expected time required to complete the life test under this censoring scheme is investigated. Finally, the numerical examples are given to illustrate some theoretical results by means of Monte-Carlo simulation.展开更多
This paper considers the parameters and reliability characteristics estimation problem of the generalized Rayleigh distribution under progressively Type-Ⅱ censoring with random removals,that is,the number of units re...This paper considers the parameters and reliability characteristics estimation problem of the generalized Rayleigh distribution under progressively Type-Ⅱ censoring with random removals,that is,the number of units removed at each failure time follows the binomial distribution.The maximum likelihood estimation and the Bayesian estimation are derived.In the meanwhile,through a great quantity of Monte Carlo simulation experiments we have studied different hyperparameters as well as symmetric and asymmetric loss functions in the Bayesian estimation procedure.A real industrial case is presented to justify and illustrate the proposed methods.We also investigate the expected experimentation time and discuss the influence of the parameters on the termination point to complete the censoring test.展开更多
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
This study utilizes a time-precedence network technique to construct two models of multi-mode resource constrained project scheduling problem with discounted cash flows （MRCPSPDCF）, individually including the progre...This study utilizes a time-precedence network technique to construct two models of multi-mode resource constrained project scheduling problem with discounted cash flows （MRCPSPDCF）, individually including the progress payment （PP） and the payment at an equal time interval （ETI）. The objective of each model is to maximize the net present value （NPV） for all cash flows in the project, subject to the related operational constraints. The models are characterized as NP-hard. A heuristic algorithm, coupled with two upper bound solutions, is proposed to efficiently solve the models and evaluate the heuristic algorithm performance which was not performed in past studies. The results show that the performance of proposed models and heuristic algorithm is good.展开更多
Objective： To evaluate the efficacy of percutaneous ethanol injection （PEI） in the adjuvant treatment of hepatocellular carcinoma （HCC） after transcatheter arterial chemoembolization （TACE） by primary end point...Objective： To evaluate the efficacy of percutaneous ethanol injection （PEI） in the adjuvant treatment of hepatocellular carcinoma （HCC） after transcatheter arterial chemoembolization （TACE） by primary end points of time to progress （TTP）. Methods： The study population consisted of 73 consecutive patients with inoperable HCC （China Classification System IIN liB）. Among them, 22 patients were treated with TACE and PEI （experimental group）, and the rest 51 were treated only with TACE （control group）, and then the time to progress （TTP） and overall survival （OS） of these two groups were analyzed. Results： The median TTP was 10 months [95% confidence interval （CI）, 7.9-12.1 months] in experimental group and 6 months （95% CI, 4.7-7.3 months） in control group. The 3-month,6-month, and 1-year Progression Free Survival （PFS） rates were respectively 77.3%, 63.6%, and 48.1% in experimental group, and 76.5%, 42.15%, and 24.8% in control group. The TTP of experimental group was significantly longer than that of control group （P 〈 0.05）. The median survival period was 17 months [95% confidence interval （CI）, 11-23 months] of experimental group and 12 months （95% CI, 10-14 months） of control group （P 〉 0.05）. Conclusion： Compared with single TACE, the combination of TACE and PEI can obviously postpone disease progress and prolong survival of HCC patients.展开更多
BACKGROUND Impressive survival outcome of our previous study in unresectable hepatocellular carcinoma(HCC)patients undergoing yttrium-90 glass microspheres transarterial radioembolization(TARE)with/without sorafenib a...BACKGROUND Impressive survival outcome of our previous study in unresectable hepatocellular carcinoma(HCC)patients undergoing yttrium-90 glass microspheres transarterial radioembolization(TARE)with/without sorafenib according to individuals’disease burden,i.e.,intrahepatic tumor load(IHT)and adverse disease features(ADFs)might partly be confounded by other treatments and underlying hepatic function.Therefore,a dedicated study focusing on treatment response and assessment of failure patterns might be a way to improve treatment outcome in addition to patient selection based on the disease burden.AIM To assess the tumor response,disease control and patterns of disease progression following TARE with/without sorafenib in unresectable HCC patients.METHODS This retrospective study was conducted in successful TARE procedures with available pre-and post-treatment imaging studies(n=169).Three treatment subgroups were(1)TARE only(TARE_alone)for IHT≤50%without ADFs,i.e.,macrovascular invasion,extrahepatic disease(EHD)and infiltrative/ill-defined HCC(n=63);(2)TARE with sorafenib(TARE_sorafenib)for IHT>50%and/or presence of ADFs(n=81);and(3)TARE only for patients who could not receive sorafenib due to contraindication or intolerance(TARE_no_sorafenib)(n=25).Objective response rate(ORR;consisted of complete response(CR)and partial response(PR)),disease control rate(DCR;consisted of CR,PR and stable disease)and failure patterns of treated,intrahepatic and extrahepatic sites were assessed using the modified response evaluation criteria in solid tumors.Time to progression(TTP)was calculated from TARE to the first radiologic progression at any site using Kaplan-Meier method.Identification of prognostic factors for TTP using the univariate Kaplan-Meier method and multivariate Cox proportional hazard model were performed in major population subgroups,TARE_alone and TARE_sorafenib.RESULTS The median radiologic follow-up time was 4.4 mo(range 0.5-48.8).In treated area,ORR was highest in TARE_sorafenib(53.1%),followed by TARE_alone(41.3%)and TARE_no_sorafenib(16%).In intrahepatic area,DCR remained highest in TARE_sorafenib(84%),followed by TARE_alone(79.4%)and TARE_no_sorafenib(44%).The overall DCR was highest in TARE_alone(79.4%),followed by TARE_sorafenib(71.6%)and TARE_no_sorafenib(40%).Dominant failure patterns were intrahepatic for both TARE_alone(44.5%)and TARE_sorafenib(38.4%).Extrahepatic progression was more common in TARE_sorafenib(32%)and TARE_no_sorafenib(40%)than in TARE_alone(12.7%).TTP was longest in TARE_alone(8.6 mo;95%CI:3.4-13.8),followed by TARE_sorafenib(5.1 mo;95%CI:4.0-6.2)and TARE_no_sorafenib(2.7 mo;95%CI:2.2-3.1).Pre-existing EHD(HR:0.37,95%CI:0.24-0.56,P<0.001)was a sole prognostic factor for TTP in TARE_sorafenib with no prognostic factor for TTP in TARE_alone.CONCLUSION TARE with/without sorafenib according to individuals’disease burden provided DCR approximately 70%with intrahepatic progression as dominant failure pattern.Extrahepatic progression was more common in procedures with initially high disease burden.展开更多
Generated by an ideal sinusoidal motion of the vertical plate, the simplest linear solution in time domain for two-dimensional regular waves is derived. The solution describes the propagation process of the plane prog...Generated by an ideal sinusoidal motion of the vertical plate, the simplest linear solution in time domain for two-dimensional regular waves is derived. The solution describes the propagation process of the plane progressive wave with a front, and will approach the linear steady- state solution as the oscillation time of the plate approaches infinity. The solution presented in this paper can be used to provide an incident wave model with analytical expression for solving the problems of diffraction and response of floating bodies in time domain.展开更多
Dear Editor,Although the incidence of prostate cancer(PCa) has decreased in recent decades in Western countries, it has gradually increased in China due to the increasingly longer life expectancy and more popular west...Dear Editor,Although the incidence of prostate cancer(PCa) has decreased in recent decades in Western countries, it has gradually increased in China due to the increasingly longer life expectancy and more popular westernized diet[1].展开更多
Time has multiple aspects and is difficult to define as one unique entity, which therefore led to multiple interpretations in physics and philosophy. However, if the perception of time is considered as a composite tim...Time has multiple aspects and is difficult to define as one unique entity, which therefore led to multiple interpretations in physics and philosophy. However, if the perception of time is considered as a composite time concept, it can be decomposed into basic invariable components for the perception of progressive and support-fixed time and into secondary components with possible association to unit-defined time or tense. Progressive time corresponds to Bergson＇s definition of duration without boundaries, which cannot be divided for measurements. Time periods are already lying in the past and fixed on different kinds of support. The human memory is the first automatic support, but any other support suitable for time registration can also be considered. The true reproduction of original time from any support requires conditions identical to the initial conditions, if not time reproduction becomes artificially modified as can be seen with a film. Time reproduction can be artificially accelerated, slowed down, extended or diminished, and also inverted from the present to the past, which only depends on the manipulation of the support, to which time is firmly linked. Tense associated to progressive and support fixed time is a psychological property directly dependent on an observer, who judges his present as immediate, his past as finished and his future as uncertain. Events can be secondarily associated to the tenses of an observer. Unit-defined time is essential for physics and normal live and is obtained by comparison of support-fixed time to systems with regular motions, like clocks. The association of time perception to time units can also be broken. Einstein＇s time units became relative, in quantum mechanics, some physicist eliminated time units, others maintained them. Nevertheless, even the complete elimination of time units is not identical to timelessness, since the psychological perception of progressive and support-fixed time still remains and cannot be ignored. It is not seizable by physical methods, but experienced by everybody in everyday life. Contemporary physics can only abandon the association of time units or tenses to the basic components in perceived time.展开更多
Interim Positron-Emission Tomography (int-PET) and the peripheral blood absolute lymphocyte/monocyte ratio at di- agnosis (ALC/AMC-DX) have been shown to be predictors for progression-free survival (PFS) and time to p...Interim Positron-Emission Tomography (int-PET) and the peripheral blood absolute lymphocyte/monocyte ratio at di- agnosis (ALC/AMC-DX) have been shown to be predictors for progression-free survival (PFS) and time to progression (TTP) in classical Hodgkin lymphoma (cHL). Therefore, we studied if the combination of ALC/AMC-DX and the (int-PET) can further stratified PFS and TTP in cHL patients. Patients were required to be diagnosed, treated, and followed with int-PET at Mayo Clinic, Rochester, Minnesota. From 2000 until 2008, 111 cHL patients qualified for the study. The median follow-up was 2.8 years (range: 0.3 - 10.4 years). Patients with a negative int-PET (N = 98) pre- sented with a higher ALC/AMC-DX (median of 2.32, range: 0.26 - 37.5) compared with patients with a positive int-PET (N = 13) (median of 0.9, range: 0.29 - 3.10), p 1.1. Group 1 experienced superior PFS and TTP in comparison with the other groups. In conclusion, the combination of ALC/AMC-DX and the int-PET provides a simple model to assess clinical outcomes in cHL.展开更多
Invariance times are stopping times T such that local martingales with respect to some reduced filtration and an equivalently changed probability measure,stopped before T,are local martingales with respect to the orig...Invariance times are stopping times T such that local martingales with respect to some reduced filtration and an equivalently changed probability measure,stopped before T,are local martingales with respect to the original model filtration and probability mcasure.They arise naturally for modeling the default time of a dealer bank,in the mathematical finance context of counterparty credit risk.Assuming an invariance time endowed with an intensity and a positive Azéma supermartingale,this work establishes a dictionary relating the semimartingale calculi in the original and reduced stochastic bases,regarding conditional expectations,martingales,stochastic integrals,random mcasure stochastic integrals,martingale rcprcscntation propertics,scmimartingalc characteristics,Markov properties,transition semigroups and infinitesimal generators,and solutions of backward stochastic differential equations.展开更多
文摘Focused on the non-statlonarity and real-time analysis of signal in flutter test with progression variable speed （FTPVS）, a new method of recursive time-frequency analysis is presented. The time-varying system is tracked on-line by building a time-varying parameter model, and then the relevant parameter spectrum can be obtained. The feasibility and advantages of the method are examined by digital simulation. The results of FTPVS at low-speed wind-tunnel promise the engineering application perspective of the method.
基金supported by the National Natural Science Foundation of China(70471057)
文摘The estimation of generalized exponential distribution based on progressive censoring with binomial removals is presented, where the number of units removed at each failure time follows a binomial distribution. Maximum likelihood estimators of the parameters and their confidence intervals are derived. The expected time required to complete the life test under this censoring scheme is investigated. Finally, the numerical examples are given to illustrate some theoretical results by means of Monte-Carlo simulation.
基金supported by the National Statistical Science Research Project of China(2019LZ32)
文摘This paper considers the parameters and reliability characteristics estimation problem of the generalized Rayleigh distribution under progressively Type-Ⅱ censoring with random removals,that is,the number of units removed at each failure time follows the binomial distribution.The maximum likelihood estimation and the Bayesian estimation are derived.In the meanwhile,through a great quantity of Monte Carlo simulation experiments we have studied different hyperparameters as well as symmetric and asymmetric loss functions in the Bayesian estimation procedure.A real industrial case is presented to justify and illustrate the proposed methods.We also investigate the expected experimentation time and discuss the influence of the parameters on the termination point to complete the censoring test.
文摘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.
文摘This study utilizes a time-precedence network technique to construct two models of multi-mode resource constrained project scheduling problem with discounted cash flows （MRCPSPDCF）, individually including the progress payment （PP） and the payment at an equal time interval （ETI）. The objective of each model is to maximize the net present value （NPV） for all cash flows in the project, subject to the related operational constraints. The models are characterized as NP-hard. A heuristic algorithm, coupled with two upper bound solutions, is proposed to efficiently solve the models and evaluate the heuristic algorithm performance which was not performed in past studies. The results show that the performance of proposed models and heuristic algorithm is good.
文摘Objective： To evaluate the efficacy of percutaneous ethanol injection （PEI） in the adjuvant treatment of hepatocellular carcinoma （HCC） after transcatheter arterial chemoembolization （TACE） by primary end points of time to progress （TTP）. Methods： The study population consisted of 73 consecutive patients with inoperable HCC （China Classification System IIN liB）. Among them, 22 patients were treated with TACE and PEI （experimental group）, and the rest 51 were treated only with TACE （control group）, and then the time to progress （TTP） and overall survival （OS） of these two groups were analyzed. Results： The median TTP was 10 months [95% confidence interval （CI）, 7.9-12.1 months] in experimental group and 6 months （95% CI, 4.7-7.3 months） in control group. The 3-month,6-month, and 1-year Progression Free Survival （PFS） rates were respectively 77.3%, 63.6%, and 48.1% in experimental group, and 76.5%, 42.15%, and 24.8% in control group. The TTP of experimental group was significantly longer than that of control group （P 〈 0.05）. The median survival period was 17 months [95% confidence interval （CI）, 11-23 months] of experimental group and 12 months （95% CI, 10-14 months） of control group （P 〉 0.05）. Conclusion： Compared with single TACE, the combination of TACE and PEI can obviously postpone disease progress and prolong survival of HCC patients.
基金Institutional review board of The University of Texas MD Anderson Cancer Center,No.DR09-0025.
文摘BACKGROUND Impressive survival outcome of our previous study in unresectable hepatocellular carcinoma(HCC)patients undergoing yttrium-90 glass microspheres transarterial radioembolization(TARE)with/without sorafenib according to individuals’disease burden,i.e.,intrahepatic tumor load(IHT)and adverse disease features(ADFs)might partly be confounded by other treatments and underlying hepatic function.Therefore,a dedicated study focusing on treatment response and assessment of failure patterns might be a way to improve treatment outcome in addition to patient selection based on the disease burden.AIM To assess the tumor response,disease control and patterns of disease progression following TARE with/without sorafenib in unresectable HCC patients.METHODS This retrospective study was conducted in successful TARE procedures with available pre-and post-treatment imaging studies(n=169).Three treatment subgroups were(1)TARE only(TARE_alone)for IHT≤50%without ADFs,i.e.,macrovascular invasion,extrahepatic disease(EHD)and infiltrative/ill-defined HCC(n=63);(2)TARE with sorafenib(TARE_sorafenib)for IHT>50%and/or presence of ADFs(n=81);and(3)TARE only for patients who could not receive sorafenib due to contraindication or intolerance(TARE_no_sorafenib)(n=25).Objective response rate(ORR;consisted of complete response(CR)and partial response(PR)),disease control rate(DCR;consisted of CR,PR and stable disease)and failure patterns of treated,intrahepatic and extrahepatic sites were assessed using the modified response evaluation criteria in solid tumors.Time to progression(TTP)was calculated from TARE to the first radiologic progression at any site using Kaplan-Meier method.Identification of prognostic factors for TTP using the univariate Kaplan-Meier method and multivariate Cox proportional hazard model were performed in major population subgroups,TARE_alone and TARE_sorafenib.RESULTS The median radiologic follow-up time was 4.4 mo(range 0.5-48.8).In treated area,ORR was highest in TARE_sorafenib(53.1%),followed by TARE_alone(41.3%)and TARE_no_sorafenib(16%).In intrahepatic area,DCR remained highest in TARE_sorafenib(84%),followed by TARE_alone(79.4%)and TARE_no_sorafenib(44%).The overall DCR was highest in TARE_alone(79.4%),followed by TARE_sorafenib(71.6%)and TARE_no_sorafenib(40%).Dominant failure patterns were intrahepatic for both TARE_alone(44.5%)and TARE_sorafenib(38.4%).Extrahepatic progression was more common in TARE_sorafenib(32%)and TARE_no_sorafenib(40%)than in TARE_alone(12.7%).TTP was longest in TARE_alone(8.6 mo;95%CI:3.4-13.8),followed by TARE_sorafenib(5.1 mo;95%CI:4.0-6.2)and TARE_no_sorafenib(2.7 mo;95%CI:2.2-3.1).Pre-existing EHD(HR:0.37,95%CI:0.24-0.56,P<0.001)was a sole prognostic factor for TTP in TARE_sorafenib with no prognostic factor for TTP in TARE_alone.CONCLUSION TARE with/without sorafenib according to individuals’disease burden provided DCR approximately 70%with intrahepatic progression as dominant failure pattern.Extrahepatic progression was more common in procedures with initially high disease burden.
基金This study is financially supported by the National Natural Science Foundation of China
文摘Generated by an ideal sinusoidal motion of the vertical plate, the simplest linear solution in time domain for two-dimensional regular waves is derived. The solution describes the propagation process of the plane progressive wave with a front, and will approach the linear steady- state solution as the oscillation time of the plate approaches infinity. The solution presented in this paper can be used to provide an incident wave model with analytical expression for solving the problems of diffraction and response of floating bodies in time domain.
基金supported by the National Natural Science Foundation of China (81902574)the Shanghai Basic Research Program (19JC1411600)+1 种基金the Shanghai Natural Science Foundation (21ZR1414500)the Shanghai Sailing Program (19YF1409800)。
文摘Dear Editor,Although the incidence of prostate cancer(PCa) has decreased in recent decades in Western countries, it has gradually increased in China due to the increasingly longer life expectancy and more popular westernized diet[1].
文摘Time has multiple aspects and is difficult to define as one unique entity, which therefore led to multiple interpretations in physics and philosophy. However, if the perception of time is considered as a composite time concept, it can be decomposed into basic invariable components for the perception of progressive and support-fixed time and into secondary components with possible association to unit-defined time or tense. Progressive time corresponds to Bergson＇s definition of duration without boundaries, which cannot be divided for measurements. Time periods are already lying in the past and fixed on different kinds of support. The human memory is the first automatic support, but any other support suitable for time registration can also be considered. The true reproduction of original time from any support requires conditions identical to the initial conditions, if not time reproduction becomes artificially modified as can be seen with a film. Time reproduction can be artificially accelerated, slowed down, extended or diminished, and also inverted from the present to the past, which only depends on the manipulation of the support, to which time is firmly linked. Tense associated to progressive and support fixed time is a psychological property directly dependent on an observer, who judges his present as immediate, his past as finished and his future as uncertain. Events can be secondarily associated to the tenses of an observer. Unit-defined time is essential for physics and normal live and is obtained by comparison of support-fixed time to systems with regular motions, like clocks. The association of time perception to time units can also be broken. Einstein＇s time units became relative, in quantum mechanics, some physicist eliminated time units, others maintained them. Nevertheless, even the complete elimination of time units is not identical to timelessness, since the psychological perception of progressive and support-fixed time still remains and cannot be ignored. It is not seizable by physical methods, but experienced by everybody in everyday life. Contemporary physics can only abandon the association of time units or tenses to the basic components in perceived time.
文摘Interim Positron-Emission Tomography (int-PET) and the peripheral blood absolute lymphocyte/monocyte ratio at di- agnosis (ALC/AMC-DX) have been shown to be predictors for progression-free survival (PFS) and time to progression (TTP) in classical Hodgkin lymphoma (cHL). Therefore, we studied if the combination of ALC/AMC-DX and the (int-PET) can further stratified PFS and TTP in cHL patients. Patients were required to be diagnosed, treated, and followed with int-PET at Mayo Clinic, Rochester, Minnesota. From 2000 until 2008, 111 cHL patients qualified for the study. The median follow-up was 2.8 years (range: 0.3 - 10.4 years). Patients with a negative int-PET (N = 98) pre- sented with a higher ALC/AMC-DX (median of 2.32, range: 0.26 - 37.5) compared with patients with a positive int-PET (N = 13) (median of 0.9, range: 0.29 - 3.10), p 1.1. Group 1 experienced superior PFS and TTP in comparison with the other groups. In conclusion, the combination of ALC/AMC-DX and the int-PET provides a simple model to assess clinical outcomes in cHL.
文摘Invariance times are stopping times T such that local martingales with respect to some reduced filtration and an equivalently changed probability measure,stopped before T,are local martingales with respect to the original model filtration and probability mcasure.They arise naturally for modeling the default time of a dealer bank,in the mathematical finance context of counterparty credit risk.Assuming an invariance time endowed with an intensity and a positive Azéma supermartingale,this work establishes a dictionary relating the semimartingale calculi in the original and reduced stochastic bases,regarding conditional expectations,martingales,stochastic integrals,random mcasure stochastic integrals,martingale rcprcscntation propertics,scmimartingalc characteristics,Markov properties,transition semigroups and infinitesimal generators,and solutions of backward stochastic differential equations.
