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Almost Sure Convergence of Proximal Stochastic Accelerated Gradient Methods
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作者 Xin Xiang Haoming Xia 《Journal of Applied Mathematics and Physics》 2024年第4期1321-1336,共16页
Proximal gradient descent and its accelerated version are resultful methods for solving the sum of smooth and non-smooth problems. When the smooth function can be represented as a sum of multiple functions, the stocha... Proximal gradient descent and its accelerated version are resultful methods for solving the sum of smooth and non-smooth problems. When the smooth function can be represented as a sum of multiple functions, the stochastic proximal gradient method performs well. However, research on its accelerated version remains unclear. This paper proposes a proximal stochastic accelerated gradient (PSAG) method to address problems involving a combination of smooth and non-smooth components, where the smooth part corresponds to the average of multiple block sums. Simultaneously, most of convergence analyses hold in expectation. To this end, under some mind conditions, we present an almost sure convergence of unbiased gradient estimation in the non-smooth setting. Moreover, we establish that the minimum of the squared gradient mapping norm arbitrarily converges to zero with probability one. 展开更多
关键词 Proximal Stochastic accelerated Method Almost Sure Convergence Composite Optimization Non-Smooth Optimization Stochastic Optimization accelerated Gradient Method
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Unsteady MHD Casson Nanofluid Flow Past an Exponentially Accelerated Vertical Plate:An Analytical Strategy
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作者 T.Aghalya R.Tamizharasi 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第7期431-460,共30页
In this study,the characteristics of heat transfer on an unsteady magnetohydrodynamic(MHD)Casson nanofluid over an exponentially accelerated vertical porous plate with rotating effects were investigated.The flow was d... In this study,the characteristics of heat transfer on an unsteady magnetohydrodynamic(MHD)Casson nanofluid over an exponentially accelerated vertical porous plate with rotating effects were investigated.The flow was driven by the combined effects of the magnetic field,heat radiation,heat source/sink and chemical reaction.Copper oxide(CuO)and titanium oxide(TiO2)are acknowledged as nanoparticle materials.The nondimensional governing equations were subjected to the Laplace transformation technique to derive closed-form solutions.Graphical representations are provided to analyze how changes in physical parameters,such as the magnetic field,heat radiation,heat source/sink and chemical reaction,affect the velocity,temperature and concentration profiles.The computed values of skin friction,heat and mass transfer rates at the surface were tabulated for various sets of input parameters.It is perceived that there is a drop in temperature due to the rise in the heat source/sink and the Prandtl number.It should be noted that a boost in the thermal radiation parameter prompts an increase in temperature.An increase in the Prandtl number,heat source/sink parameter,time and a decrease in the thermal radiation parameter result in an increase in theNusselt number.The computed values of the skin friction,heat andmass transfer rates at the surface were tabulated for various values of the flow parameters.The present results were compared with those of previously published studies andwere found to be in excellent agreement.This research has practical applications in areas such as drug delivery,thermal medicine and cancer treatment. 展开更多
关键词 Thermal radiation radiative flux NANOFLUID copper oxide titanium oxide accelerated plate
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Clinical Practice of Evidence-Based PDCA Cycle Management Model in Accelerated Recovery of Lung Cancer Patients
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作者 Lu Kang Juan Yuan +1 位作者 Dandan Liu Bo Deng 《Journal of Cancer Therapy》 2024年第4期130-140,共11页
Objective: To explore the nursing effect of evidence-based PDCA cycle management mode in accelerated rehabilitation of patients undergoing thoracoscopic lung cancer radical surgery. Methods: 104 patients who underwent... Objective: To explore the nursing effect of evidence-based PDCA cycle management mode in accelerated rehabilitation of patients undergoing thoracoscopic lung cancer radical surgery. Methods: 104 patients who underwent thoracoscopic lung cancer radical surgery in our hospital from June 2022 to February 2023 were randomly divided into control group and intervention group, with 52 cases in each group. The control group implemented evidence-based ERAS clinical pathway management, while the intervention group implemented evidence-based PDCA cycle quality management. The postoperative recovery of the two groups of patients was compared. Results: The postoperative recovery of the intervention group was significantly better than that of the control group. The first time to get out of bed, the first time to eat, the duration of chest drainage tube placement, and the length of hospital stay were significantly shorter than those of the control group. The incidence of postoperative chest complications and hospitalization costs were significantly lower than those of the control group, and patient satisfaction was significantly higher than that of the control group (P Conclusion: Evidence-based PDCA cycle quality management mode can effectively improve the implementation quality of accelerated rehabilitation nursing for patients undergoing thoracoscopic lung cancer radical surgery, and it is worthy of clinical promotion. 展开更多
关键词 EVIDENCE-BASED PDCA Cycle Thoracoscopic Lung Cancer Radical Surgery accelerated Rehabilitation
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The Accelerated Expansion of the Universe in the Light of the Maximum Ordinality Principle
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作者 Corrado Giannantoni 《Journal of Applied Mathematics and Physics》 2024年第2期585-602,共18页
The main aim of the paper is to present (and at the same time offer) a differ-ent perspective for the analysis of the accelerated expansion of the Universe. A perspective that can surely be considered as being “in pa... The main aim of the paper is to present (and at the same time offer) a differ-ent perspective for the analysis of the accelerated expansion of the Universe. A perspective that can surely be considered as being “in parallel” to the tradition-al ones, such as those based, for example, on the hypotheses of “Dark Matter” and “Dark Energy”, or better as a “com-possible” perspective, because it is not understood as being “exclusive”. In fact, it is an approach that, when con-firmed by experimental results, always keeps its validity from an “operative” point of view. This is because, in analogy to the traditional perspectives, on the basis of Popper’s Falsification Principle the corresponding “Generative” Logic on which it is based has not the property of the perfect induction. The basic difference then only consists in the fact that the Evolution of the Universe is now modeled by considering the Universe as a Self-Organizing System, which is thus analyzed in the light of the Maximum Ordinality Principle. 展开更多
关键词 accelerated Expansion of the Universe Maximum Ordinality Principle Incip-ient Differential Calculus
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Designing Adaptive Multiple Dependent State Sampling Plan for Accelerated Life Tests 被引量:1
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作者 Pramote Charongrattanasakul Wimonmas Bamrungsetthapong Poom Kumam 《Computer Systems Science & Engineering》 SCIE EI 2023年第8期1631-1651,共21页
A novel adaptive multiple dependent state sampling plan(AMDSSP)was designed to inspect products from a continuous manufacturing process under the accelerated life test(ALT)using both double sampling plan(DSP)and multi... A novel adaptive multiple dependent state sampling plan(AMDSSP)was designed to inspect products from a continuous manufacturing process under the accelerated life test(ALT)using both double sampling plan(DSP)and multiple dependent state sampling plan(MDSSP)concepts.Under accelerated conditions,the lifetime of a product follows the Weibull distribution with a known shape parameter,while the scale parameter can be determined using the acceleration factor(AF).The Arrhenius model is used to estimate AF when the damaging process is temperature-sensitive.An economic design of the proposed sampling plan was also considered for the ALT.A genetic algorithm with nonlinear optimization was used to estimate optimal plan parameters to minimize the average sample number(ASN)and total cost of inspection(TC)under both producer’s and consumer’s risks.Numerical results are presented to support the AMDSSP for the ALT,while performance comparisons between the AMDSSP,the MDSSP and a single sampling plan(SSP)for the ALT are discussed.Results indicated that the AMDSSP was more flexible and efficient for ASN and TC than the MDSSP and SSP plans under accelerated conditions.The AMDSSP also had a higher operating characteristic(OC)curve than both the existing sampling plans.Two real datasets of electronic devices for the ALT at high temperatures demonstrated the practicality and usefulness of the proposed sampling plan. 展开更多
关键词 accelerated life test acceleration factor adaptive of multiple dependent state sampling plan average sample number total cost of inspection weibull distribution
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Quality Improvement of Recycled Concrete Aggregate by Accelerated Carbonation under Different Pressure
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作者 丁亚红 武军 +3 位作者 ZHANG Xianggang XU Ping NING Wei LI Yajing 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2023年第3期623-631,共9页
Due to the presence of old mortar (OM) and interfacial transition zone (ITZ),recycled concrete aggregate (RCA) is inferior to natural aggregate (NA).The purpose of this paper was to study the effect of accelerated car... Due to the presence of old mortar (OM) and interfacial transition zone (ITZ),recycled concrete aggregate (RCA) is inferior to natural aggregate (NA).The purpose of this paper was to study the effect of accelerated carbonation on the macro-properties and micro-properties of RCA under different pressure(0.05,0.15,0.30 MPa).The macro-property tests included colour change,apparent density,water absorption,and crushing value of RCA.The micro-property tests included scanning electron microscopy (SEM),X-ray diffraction (XRD),thermogravimetry-differential scanning calorimetry (TG-DSC),and Vickers micro-hardness(VMH).The results showed that the change trends of apparent density,water absorption,and crushing value of RCA displayed exponential relationships as pressure increasing,with the optimum pressure of 0.30 MPa.SEM images indicated that the calcite caused by the hydration products in RCA and the Ca(OH)_(2) derived from saturated lime water improved the properties of RCA;as the apparent density increased,the water absorption and crushing value decreased.The results of XRD and TG-DSC indicated that,as the pressure increased,the masses of Ca(OH)_(2) in carbonated RCA gradually decreased,while those of CaCO_(3) gradually increased,which demonstrated that the carbonation degree gradually increased.Besides,ITZ-2 was the weakest phase in RCA,but its improvement degree of VMH by accelerated carbonation was higher than that of OM.However,RCA was not completely carbonated,but only carbonated in a certain depth after 24 h accelerated carbonation. 展开更多
关键词 recycled concrete aggregate treatment method accelerated carbonation interfacial transition zone saturated lime water CALCITE
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A Novel Process of CO_(2) Reduction and CO_(2) Sequestration Through an Innovative Accelerated Carbonation Technique
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作者 Akshay Ramesh Bura B Kondraivendhan 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2023年第5期1105-1117,共13页
The efiect of an innovative accelerated carbonation curing technique was evaluated on concrete containing natural zeolite powder and fine aggregate as partial replacement to alleviate the CO_(2) emission up to a certa... The efiect of an innovative accelerated carbonation curing technique was evaluated on concrete containing natural zeolite powder and fine aggregate as partial replacement to alleviate the CO_(2) emission up to a certain extent from the concrete production industry and improve sequestration of CO_(2) into the concrete matrix in a stable form.An accelerated carbonation curing was accomplished by subjecting the concrete specimens to 0.5 and 0.75 M concentrations of sodium bicarbonate(NaHCO_(3)) solutions up to a curing age of 180 days after the initial 28 days of normal water curing.Tests for carbonation depth,pH value,compressive strength,calcium carbonate(CaCO_(3))content,X-ray difiraction,and thermogravimetric(TGA)analyses and Fourier transform infrared spectroscopy(FTIR)were performed to measure the extent of carbonation.The obtained results showed an increment in average compressive strength for the zeolite concrete(ZLC)mixes exposed to accelerated carbonation curing.The ZLC mixes exposed to increasing NaHCO_(3) solution concentration and exposure period exhibited greater carbonation depth and decreased pH at each depth interval indicating higher CO_(2) sequestration within the concrete matrix.The results obtained from the microstructural analysis(XRD,TGA,and FTIR)and CaCO_(3) content measurements confirm that the higher amount of CaCO_(3) formation provides a clear indication of the carbonation enhancement and CO_(2) sequestration within the concrete matrix and in turn contributing to the global warming reduction. 展开更多
关键词 CO_(2)sequestration accelerated carbonation natural zeolite calcium carbonate
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Inference for accelerated bivariate dependent competing risks model based on Archimedean copulas under progressive censoring
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作者 ZHANG Chun-fang SHI Yi-min WANG Liang 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2023年第4期475-492,共18页
Dependent competing risks model is a practical model in the analysis of lifetime and failure modes.The dependence can be captured using a statistical tool to explore the re-lationship among failure causes.In this pape... Dependent competing risks model is a practical model in the analysis of lifetime and failure modes.The dependence can be captured using a statistical tool to explore the re-lationship among failure causes.In this paper,an Archimedean copula is chosen to describe the dependence in a constant-stress accelerated life test.We study the Archimedean copula based dependent competing risks model using parametric and nonparametric methods.The parametric likelihood inference is presented by deriving the general expression of likelihood function based on assumed survival Archimedean copula associated with the model parameter estimation.Combining the nonparametric estimation with progressive censoring and the non-parametric copula estimation,we introduce a nonparametric reliability estimation method given competing risks data.A simulation study and a real data analysis are conducted to show the performance of the estimation methods. 展开更多
关键词 dependent competing risks model accelerated life tests Archimedean copula nonparametric reliability estimation
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Synergistic Use of CO_(2) Pretreatment and Accelerated Carbonation Curing for Maximum Recycling of Steel Slag
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作者 刘姚君 AN Xiaopeng +2 位作者 LIANG Huichao YU Kexiao WANG Lan 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2023年第3期530-537,共8页
Two carbonation approaches are considered for studying the effects on the hardening mechanisms of slurries made of 100 wt%electric arc furnace steel slag (EAF) slag or 80 wt%EAF slag incorporating 20 wt% of Portland c... Two carbonation approaches are considered for studying the effects on the hardening mechanisms of slurries made of 100 wt%electric arc furnace steel slag (EAF) slag or 80 wt%EAF slag incorporating 20 wt% of Portland cement,which are applied during the hot-stage pretreatment with simulated gas for raw steel slag or the accelerated carbonation curing of slurry.The mechanical strengths,carbonate products,microstructures and CO_(2) uptakes were quantitatively investigated.Results manifest that accelerated carbonation curing increases the compressive strengths of steel slag slurry,from 17.1 MPa (binder of 80 wt% EAF and 20 wt%cement under standard moisture curing) to 36.0 MPa (binder of 80 wt%EAF and 20 wt%cement under accelerated carbonation curing),with a CO_(2) uptake of 52%.In contrast,hot-stage carbonation applied during the pretreatment of steel slag increases the compressive strengths to 43.7 MPa (binder of 80 wt%carbonated EAF and 20 wt%cement under accelerated carbonation curing),with a CO_(2) uptake of 67%.Hotstage carbonation of steel slag is found for particle agglomeration,minerals remodeling and calcite formed,thus causing an activated steel slag with a dense structure and more active components.Accelerated carbonation curing of steel slag slurry paste results in the newly formed amorphous CaCO_(3),calcite crystalline and silica gels that covered the pores of the matrix,facilitating microstructure densification and strength improvement.Adopting the combinative methods of the hot-stage CO_(2) pretreatment and accelerated carbonation curing creates a promising high-volume steel slag-based binder with high strengths and CO_(2) storage. 展开更多
关键词 high-volume steel slag binders hot-stage CO_(2)pretreatment accelerated carbonation curing CO_(2)storage
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Molecular insight into the GaP(110)-water interface using machine learning accelerated molecular dynamics
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作者 Xue-Ting Fan Xiao-Jian Wen +1 位作者 Yong-Bin Zhuang Jun Cheng 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第7期239-247,I0006,共10页
GaP has been shown to be a promising photoelectrocatalyst for selective CO_(2)reduction to methanol.Due to the relevance of the interface structure to important processes such as electron/proton transfer,a detailed un... GaP has been shown to be a promising photoelectrocatalyst for selective CO_(2)reduction to methanol.Due to the relevance of the interface structure to important processes such as electron/proton transfer,a detailed understanding of the GaP(110)-water interfacial structure is of great importance.Ab initio molecular dynamics(AIMD)can be used for obtaining the microscopic information of the interfacial structure.However,the GaP(110)-water interface cannot converge to an equilibrated structure at the time scale of the AIMD simulation.In this work,we perform the machine learning accelerated molecular dynamics(MLMD)to overcome the difficulty of insufficient sampling by AIMD.With the help of MLMD,we unravel the microscopic information of the structure of the GaP(110)-water interface,and obtain a deeper understanding of the mechanisms of proton transfer at the GaP(110)-water interface,which will pave the way for gaining valuable insights into photoelectrocatalytic mechanisms and improving the performance of photoelectrochemical cells. 展开更多
关键词 PHOTOELECTROCATALYSIS GaP(110)-water interface Machine learning accelerated molecular dynamics
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A Rare Entity of Accelerated Chronic Lymphocytic Leukemia: A Report of Two Cases and Review of Literature
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作者 Zahra Kmira Ben Yahya Noura +7 位作者 Chembah Wafa Ben Sayed Nesrine Chiba Dorra Bouteraa Walid Zaier Monia Ben Youssef Yosra Haifa Regaieg Khelif Abderrahim 《Health》 2023年第8期861-870,共10页
Background: Accelerated-chronic lymphocytic leukemia (A-CLL) is a rare disease entity as it represents less than 1% of all reported cases of chronic lymphoid leukemia (CLL). Moreover, it is most likely an under diagno... Background: Accelerated-chronic lymphocytic leukemia (A-CLL) is a rare disease entity as it represents less than 1% of all reported cases of chronic lymphoid leukemia (CLL). Moreover, it is most likely an under diagnosed entity due to its rarity and the non-standardized practice of lymph node biopsy in CLL. Purpose: The aims of our work are to establish the diagnosis of A-CLL and to study the prognosis and treatment of this rare entity. Method: here, we report the clinical presentation and the follow up of two cases of A-CLL. Results: Distinguishing Richter transformation (RT) from A-CLL is important as it may result in a major change in disease management. The prognosis of A-CLL is intermediate between CLL and RT. The prognosis is mainly poor due to a predominance of poor prognostic markers including an increasing number of p53-positive cases. Conclusion: To this date, no prospective study has been led to define the best treatment for A-CLL. The shorter survival of A-CLL when compared to typical CLL implies the need of a more aggressive treatment. 展开更多
关键词 accelerated Chronic Lymphocytic Leukemia Richter Transformation PROGNOSIS Treatment
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The Accelerated Expansion of the Universe
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作者 Ardeshir Irani 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2023年第2期407-410,共4页
We use experimental data from Distant Type 1a Supernovae to calculate the Observed Magnitude (m - M) which is the Apparent Magnitude (m) minus the Absolute Magnitude (M) for different values of the Redshift ... We use experimental data from Distant Type 1a Supernovae to calculate the Observed Magnitude (m - M) which is the Apparent Magnitude (m) minus the Absolute Magnitude (M) for different values of the Redshift z which gives us the Distance Modulus. Then, we calculate the average velocity and average acceleration for different z values and plot them as a function of time. The expansion of the space of our 3-D Universe is exponential and it will end with a Big Bang as four 3-D Universes of which we are one will come together to form one 4-D expanding spatial Universe. 展开更多
关键词 Distance Modulus REDSHIFT accelerated Expansion Exponentially Expanding Space Big Bang
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Research and Enlightenment of Accelerated Approval Pathway in China
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作者 Li He Huang Zhe 《Asian Journal of Social Pharmacy》 2023年第1期1-7,共7页
Objective To provide suggestions to improve the system of accelerated review and approval in China and to speed up the development and marketing of innovative drugs.Methods A comparative analysis was made to study the... Objective To provide suggestions to improve the system of accelerated review and approval in China and to speed up the development and marketing of innovative drugs.Methods A comparative analysis was made to study the accelerated review,conditional approval and breakthrough therapy between China and the United States.Combined with the implementation of accelerated pathway in China,some suggestions were put forward.Results and Conclusion The implementation of accelerated drug review and approval system can significantly speed up the process of new drug development,which will improve the accessibility of innovative drugs.However,there are some problems in the review procedures and the implementation of supportive documents in China.In view of the above problems and combined with the experiences of US FDA,we should strengthen the construction of institutional system and reviewer team,and improve the efficiency of drug research and development. 展开更多
关键词 accelerated review and approval priority review breakthrough therapy conditional approval
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A study of grid failure mode drivers and methods for accelerated life testing of a 30cm diameter ion thruster
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作者 孙明明 龙建飞 +3 位作者 陈娟娟 杨威 郭伟龙 陈新伟 《Plasma Science and Technology》 SCIE EI CAS CSCD 2023年第11期122-132,共11页
In view of the high cost caused by the 1:1 lifetime verification test of ion thrusters,the lifetime acceleration test should be considered.This work uses the PIC-MCC(Particle-in-Cell MonteCarlo Collision)method to ana... In view of the high cost caused by the 1:1 lifetime verification test of ion thrusters,the lifetime acceleration test should be considered.This work uses the PIC-MCC(Particle-in-Cell MonteCarlo Collision)method to analyze the five failure factors that lead to the failure of the accelerator grid of a 30 cm diameter ion thruster under the working mode of 5 k W.Meanwhile,the acceleration stress levels corresponding to different failure factors are obtained.The results show that background pressure has the highest stress level on the grid's erosion.The accelerator grid aperture's mass sputtering rate under the rated vacuum degree(1×10^(-4)Pa)of 5 k W work mode is 8.78 times that of the baseline vacuum degree(1×10^(-6)Pa),and the mass sputtering rate under worse vacuum degree(5×10^(-3)Pa)is 5.08 times that of 1×10^(-4)Pa.Under the influence of the other four failure factors,namely,the voltage of the accelerator grid,upstream plasma density,the screen grid voltage and mass utilization efficiency,the mass sputtering rates of the accelerator grid hole are 2.32,2.67,1.98 and 2.51 times those of the accelerator grid hole under baseline condition,respectively.The ion sputtering results of two 30 cm diameter ion thrusters(both installed with new grids assembly)after working for 1000 h show that the mass sputtering rate of the accelerator grid hole under vacuum conditions of 5×10^(-3)Pa is 4.54 times that under the condition of 1×10^(-4)Pa,and the comparison error between simulation results and test results of acceleration stress is about 10%.In the subsequent ion thruster lifetime verification,the working vacuum degree can be adjusted according to the acceleration stress level of background pressure,so as to shorten the test time and reduce the test cost. 展开更多
关键词 ion thruster failure factors acceleration stress level
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Residual lifetime prediction model of nonlinear accelerated degradation data with measurement error 被引量:12
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作者 Zhongyi Cai Yunxiang Chen +1 位作者 Qiang Zhang Huachun Xiang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2017年第5期1028-1038,共11页
For the product degradation process with random effect(RE), measurement error(ME) and nonlinearity in step-stress accelerated degradation test(SSADT), the nonlinear Wiener based degradation model with RE and ME is bui... For the product degradation process with random effect(RE), measurement error(ME) and nonlinearity in step-stress accelerated degradation test(SSADT), the nonlinear Wiener based degradation model with RE and ME is built. An analytical approximation to the probability density function(PDF) of the product's lifetime is derived in a closed form. The process and data of SSADT are analyzed to obtain the relation model of the observed data under each accelerated stress. The likelihood function for the population-based observed data is constructed. The populationbased model parameters and its random coefficient prior values are estimated. According to the newly observed data of the target product in SSADT, an analytical approximation to the PDF of its residual lifetime(RL) is derived in accordance with its individual degradation characteristics. The parameter updating method based on Bayesian inference is applied to obtain the posterior value of random coefficient of the RL model. A numerical example by simulation is analyzed to verify the accuracy and advantage of the proposed model. 展开更多
关键词 accelerated degradation test RESIDUAL LIFETIME (RL) PREDICTION measurement error RANDOM effect NONLINEARITY
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Simultaneous modulated accelerated radiation therapy for esophageal cancer:A feasibility study 被引量:12
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作者 Wu-Zhe Zhang Jian-Zhou Chen +6 位作者 De-Rui Li Zhi-Jian Chen Hong Guo Ting-Ting Zhuang Dong-Sheng Li Ming-Zhen Zhou Chuang-Zhen Chen 《World Journal of Gastroenterology》 SCIE CAS 2014年第38期13973-13980,共8页
AIM:To establish the feasibility of simultaneous modulated accelerated radiation therapy(SMART) in esophageal cancer(EC).METHODS:Computed tomography(CT)datasets of 10patients with upper or middle thoracic squamous cel... AIM:To establish the feasibility of simultaneous modulated accelerated radiation therapy(SMART) in esophageal cancer(EC).METHODS:Computed tomography(CT)datasets of 10patients with upper or middle thoracic squamous cell EC undergoing chemoradiotherapy were used to generate SMART,conventionally-fractionated three-dimensional conformal radiotherapy(3DCRT)and intensity-modulated radiation therapy(cf-IMRT)plans,respectively.The gross target volume(GTV)of the esophagus,positive regional lymph nodes(LN),and suspected lymph nodes(LN±)were contoured for each patient.The clinical target volume(CTV)was delineated with 2-cm longitudinal and 0.5-to 1.0-cm radial margins with respect to the GTV and with 0.5-cm uniform margins for LN and LN(±).For the SMART plans,there were two planning target volumes(PTVs):PTV66=(GTV+LN)+0.5 cm and PTV54=CTV+0.5 cm.For the 3DCRT and cfIMRT plans,there was only a single PTV:PTV60=CTV+0.5 cm.The prescribed dose for the SMART plans was 66 Gy/30 F to PTV66 and 54 Gy/30 F to PTV54.The dose prescription to the PTV60 for both the 3DCRT and cf-IMRT plans was set to 60 Gy/30 F.All the plans were generated on the Eclipse 10.0 treatment planning system.Fulfillment of the dose criteria for the PTVs received the highest priority,followed by the spinal cord,heart,and lungs.The dose-volume histograms were compared.RESULTS:Clinically acceptable plans were achieved for all the SMART,cf-IMRT,and 3DCRT plans.Compared with the 3DCRT plans,the SMART plans increased the dose delivered to the primary tumor(66Gy vs 60 Gy),with improved sparing of normal tissues in all patients.The Dmax of the spinal cord,V20 of the lungs,and Dmean and V50 of the heart for the SMART and 3DCRT plans were as follows:38.5±2.0 vs 44.7±0.8(P=0.002),17.1±4.0 vs 25.8±5.0(P=0.000),14.4±7.5 vs 21.4±11.1(P=0.000),and 4.9±3.4vs 12.9±7.6(P=0.000),respectively.In contrast to the cf-IMRT plans,the SMART plans permitted a simultaneous dose escalation(6 Gy)to the primary tumor while demonstrating a significant trend of a lower irradiation dose to all organs at risk except the spinal cord,for which no significant difference was found.CONCLUSION:SMART offers the potential for a 6Gy simultaneous escalation in the irradiation dose delivered to the primary tumor of EC and improves the sparing of normal tissues. 展开更多
关键词 SIMULTANEOUS MODULATED accelerated radia-tion ther
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Accelerated Exhumation During the Cenozoic in the Dabie Mountains: Evidence from Fission-Track Ages 被引量:4
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作者 WANG Guocan YANG Weiran 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 1998年第4期409-419,共11页
Zircon and apatite fission-track dating indicates that the exhumation of the Dabie Mountains tended to be accelerated in the Cenozoic and that the exhumation of the eastern Dabie Mountains was more and more intense fr... Zircon and apatite fission-track dating indicates that the exhumation of the Dabie Mountains tended to be accelerated in the Cenozoic and that the exhumation of the eastern Dabie Mountains was more and more intense from south to north, which is in accordance with the more and more intense dissection from south to north, as is reflected by the modern geomorphologic features of the Dabie Mountains. The accelerated exhumation during the Cenozoic was related to the high elevation of the Dabie Mountains resulting from Late Cretaceous-Palaeogene detachment faulting and subsequent fault-block uplift and subsidence. The average elevation at that time was at least about 660 m higher than that at the present. The intense exhumation lagged behind intense uplift. 展开更多
关键词 DABIE Mountains accelerated EXHUMATION CENOZOIC FISSION-TRACK age
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Effects of Accelerated Aging on Physiological and Biochemical Characteristics of Waxy and Non-waxy Wheat Seeds 被引量:9
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作者 QIN Peng KONG Zhiyou +1 位作者 LIAO Xiaohong LIU Yeju 《Journal of Northeast Agricultural University(English Edition)》 CAS 2011年第2期7-12,共6页
Experiments were conducted to evaluate the physiological and the biochemical characteristics of waxy wheat seeds under accelerated aging conditions. Five waxy wheat lines, which were Waxy 1, Waxy 4, Waxy 8, Waxy 9, an... Experiments were conducted to evaluate the physiological and the biochemical characteristics of waxy wheat seeds under accelerated aging conditions. Five waxy wheat lines, which were Waxy 1, Waxy 4, Waxy 8, Waxy 9, and Waxy 15; and five non-waxy wheat lines: S-39, 04J89, Jan-81, Ⅲ42-4, and Ⅲ10 were studied. The seeds were subjected to accelerated aging at 40℃, 45℃, 50℃, 55℃, and 60℃, and 90% relative humidity for 0, 2, 4, 6, and 8 days, respectively. The results showed a gradual increase in conductivity and decrease in germination rate during accelerated aging. SOD, POD and CAT activities increased at low-grade treatment, but decreased at severe treatment. On the other hand, the soluble protein content decreased at 45℃, but successively increased, then decreased 50℃. From the above study, it showed that 90% RH at 55℃ was the best accelerated aging condition for optimum efficiency in a shorter period. 展开更多
关键词 accelerated aging waxy wheat non-waxy wheat physiological and biochemical characteristics
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Estimation for constant-stress accelerated life test from generalized half-normal distribution 被引量:4
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作者 Liang Wang Yimin Shi 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2017年第4期810-816,共7页
In the constant-stress accelerated life test, estimation issues are discussed for a generalized half-normal distribution under a log-linear life-stress model. The maximum likelihood estimates with the corresponding fi... In the constant-stress accelerated life test, estimation issues are discussed for a generalized half-normal distribution under a log-linear life-stress model. The maximum likelihood estimates with the corresponding fixed point type iterative algorithm for unknown parameters are presented, and the least square estimates of the parameters are also proposed. Meanwhile, confidence intervals of model parameters are constructed by using the asymptotic theory and bootstrap technique. Numerical illustration is given to investigate the performance of our methods. 展开更多
关键词 accelerated life test maximum LIKELIHOOD ESTIMATION least square method BOOTSTRAP technique ASYMPTOTIC distribution
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Periodontally accelerated osteogenic orthodontics with platelet-rich fibrin in an adult patient with periodontal disease:A case report and review of literature 被引量:7
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作者 Min Xu Xiao-Yu Sun Jian-Guang Xu 《World Journal of Clinical Cases》 SCIE 2021年第6期1367-1378,共12页
BACKGROUND In the clinical scenario,adult patients with periodontal diseases and dental malformation,characterized by dental crowding in lower anterior teeth with the thin biotype,often require orthodontic treatment.T... BACKGROUND In the clinical scenario,adult patients with periodontal diseases and dental malformation,characterized by dental crowding in lower anterior teeth with the thin biotype,often require orthodontic treatment.This case report aimed to evaluate the clinical and radiographic outcomes of periodontally accelerated osteogenic orthodontics(PAOO)combined with autologous platelet-rich fibrin(PRF)in an adult patient with class I malocclusion along with dental crowding,a thin periodontal biotype,and buccal plate deficiency.CASE SUMMARY A 32-year-old female complaining of dental crowding and gingival bleeding was referred to the orthodontic clinic.The patient underwent periodontal risk assessment prior to orthodontic treatment.She was diagnosed with a high risk of gingival recession due to dental crowding,root prominence,loss of buccal plates,and a thin gingival tissue biotype.The treatment regimen included PAOO combined with autologous PRF for alveolar augmentation and interproximal enamel reduction for moderate dental crowding.Clinically,PAOO-assisted orthodontic tooth movement in this case showed enhanced periodontium remodeling.Radiographic outcomes also showed statistically significant improvements(P<0.01)in the mandibular buccal alveolar bone.CONCLUSION This case report suggests the combination of autologous PRF with PAOO to enhance bone augmentation and long-term tissue support in adult orthodontic patients with periodontal disease. 展开更多
关键词 Periodontally accelerated osteogenic orthodontics Orthodontic tooth movement Platelet-rich fibrin Bone augmentation Periodontal biotype Case report
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