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模糊限制语probably的类联接典型范式及其情态功能研究 被引量:2
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作者 王月丽 《西南科技大学学报(哲学社会科学版)》 2013年第6期81-86,101,共7页
基于美国当代英语语料库COCA的研究发现:1)与probably共现频数最高的动词、名词和形容词预见了模糊限制语probably最常用的语法构式为"be+probably+adj.+n."与"will/would+probably+v."。2)模糊限制语probably有居... 基于美国当代英语语料库COCA的研究发现:1)与probably共现频数最高的动词、名词和形容词预见了模糊限制语probably最常用的语法构式为"be+probably+adj.+n."与"will/would+probably+v."。2)模糊限制语probably有居中的句法位置趋向,主要发挥认知评价与缓和语气,调节人际关系的语用功能。3)模糊限制语probably的类联接典型范式具有精确话语信息、表达礼貌意义以及传达认知评价的主、客观情态取向的三重情态功能,其情态意义表达强度呈现强弱渐进的变化趋势。 展开更多
关键词 模糊限制语 probably 搭配 类联接 情态功能
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probably与maybe的用法比较
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作者 孟凡茂 孟凡艳 《语言教育》 2002年第7期40-40,共1页
初学英语的人,往往把probab—ly(=most likely)一词与maybe(=per-haps)混同起来。但是,无论在意义上还是用法上,两者都有一些差别。首先,在意义方面。
关键词 probably MAYBE LIKELY LEAVE 法上 THINK perhaps TOMORROW 通讯地址 临沂师范学院
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LANGUAGE CORNER Lesson 20:I Probably Won't Sleep Well Tonight
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《China Today》 2006年第8期80-81,共2页
关键词 LANGUAGE CORNER Lesson 20:I probably Won’t Sleep Well Tonight
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You've got questions? She's got answers(But you probably won't like them)
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《The World of Chinese》 2024年第1期126-126,共1页
Dear Ayi,I think my son’s elementary teachers are irresponsible!He always comes home with his water bottle still full,despite my repeated messages to his teachers reminding them to encourage him to drink more water.S... Dear Ayi,I think my son’s elementary teachers are irresponsible!He always comes home with his water bottle still full,despite my repeated messages to his teachers reminding them to encourage him to drink more water.Should I move him to another school next year? 展开更多
关键词 probably ELEMENTARY ANSWER
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You've got questions?She's got answers(But you probably won't like them)
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《The World of Chinese》 2024年第2期126-126,共1页
Dear Ayi,I tried to avoid crowds this Labor Day holiday by visiting a small village in the middle of nowhere.Iended up bored out of my mind.Where can I go that's quiet and fun?
关键词 tried probably ANSWER
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The Probability Density Function Related to Shallow Cumulus Entrainment Rate and Its Influencing Factors in a Large-Eddy Simulation 被引量:2
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作者 Lei ZHU Chunsong LU +5 位作者 Xiaoqi XU Xin HE Junjun LI Shi LUO Yuan WANG Fan WANG 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第1期173-187,共15页
The process of entrainment-mixing between cumulus clouds and the ambient air is important for the development of cumulus clouds.Accurately obtaining the entrainment rate(λ)is particularly important for its parameteri... The process of entrainment-mixing between cumulus clouds and the ambient air is important for the development of cumulus clouds.Accurately obtaining the entrainment rate(λ)is particularly important for its parameterization within the overall cumulus parameterization scheme.In this study,an improved bulk-plume method is proposed by solving the equations of two conserved variables simultaneously to calculateλof cumulus clouds in a large-eddy simulation.The results demonstrate that the improved bulk-plume method is more reliable than the traditional bulk-plume method,becauseλ,as calculated from the improved method,falls within the range ofλvalues obtained from the traditional method using different conserved variables.The probability density functions ofλfor all data,different times,and different heights can be well-fitted by a log-normal distribution,which supports the assumed stochastic entrainment process in previous studies.Further analysis demonstrate that the relationship betweenλand the vertical velocity is better than other thermodynamic/dynamical properties;thus,the vertical velocity is recommended as the primary influencing factor for the parameterization ofλin the future.The results of this study enhance the theoretical understanding ofλand its influencing factors and shed new light on the development ofλparameterization. 展开更多
关键词 large-eddy simulation cumulus clouds entrainment rate probability density functions spatial and temporal distribution
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Effectiveness of antibiotic prophylaxis for acute esophageal variceal bleeding in patients with band ligation: A large observational study 被引量:1
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作者 Chikamasa Ichita Sayuri Shimizu +4 位作者 Tadahiro Goto Uojima Haruki Naoya Itoh Masao Iwagami Akiko Sasaki 《World Journal of Gastroenterology》 SCIE CAS 2024年第3期238-251,共14页
BACKGROUND Esophageal variceal bleeding is a severe complication associated with liver cirrhosis and typically necessitates endoscopic hemostasis.The current standard treatment is endoscopic variceal ligation(EVL),and... BACKGROUND Esophageal variceal bleeding is a severe complication associated with liver cirrhosis and typically necessitates endoscopic hemostasis.The current standard treatment is endoscopic variceal ligation(EVL),and Western guidelines recom-mend antibiotic prophylaxis following hemostasis.However,given the impro-vements in prognosis for variceal bleeding due to advancements in the management of bleeding and treatments of liver cirrhosis and the global concerns regarding the emergence of multidrug-resistant bacteria,there is a need to reassess the use of routine antibiotic prophylaxis after hemostasis.AIM To evaluate the effectiveness of antibiotic prophylaxis in patients treated for EVL.METHODS We conducted a 13-year observational study using the Tokushukai medical database across 46 hospitals.Patients were divided into the prophylaxis group(received antibiotics on admission or the next day)and the non-prophylaxis group(did not receive antibiotics within one day of admission).The primary outcome was composed of 6-wk mortality,4-wk rebleeding,and 4-wk spontaneous bacterial peritonitis(SBP).The secondary outcomes were each individual result and in-hospital mortality.A logistic regression with inverse probability of treatment weighting was used.A subgroup analysis was conducted based on the Child-Pugh classification to determine its influence on the primary outcome measures,while sensitivity analyses for antibiotic type and duration were also performed.RESULTS Among 980 patients,790 were included(prophylaxis:232,non-prophylaxis:558).Most patients were males under the age of 65 years with a median Child-Pugh score of 8.The composite primary outcomes occurred in 11.2%of patients in the prophylaxis group and 9.5%in the non-prophylaxis group.No significant differences in outcomes were observed between the groups(adjusted odds ratio,1.11;95%confidence interval,0.61-1.99;P=0.74).Individual outcomes such as 6-wk mortality,4-wk rebleeding,4-wk onset of SBP,and in-hospital mortality were not significantly different between the groups.The primary outcome did not differ between the Child-Pugh subgroups.Similar results were observed in the sensitivity analyses.CONCLUSION No significant benefit to antibiotic prophylaxis for esophageal variceal bleeding treated with EVL was detected in this study.Global reassessment of routine antibiotic prophylaxis is imperative. 展开更多
关键词 Esophageal varices Endoscopic hemostasis Antibiotic prophylaxis Liver cirrhosis Inverse probability of treatment weighting
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Identification of Abnormal 51 CTA/CTG Expansion as Probably the Shortest Pathogenic Allele for Spinocerebellar Ataxia-8 in China 被引量:1
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作者 Minjin Wang Shuo Guo +4 位作者 Wencong Yao Jun Wang Jianxia Tao Yanbing Zhou Binwu Ying 《Neuroscience Bulletin》 SCIE CAS CSCD 2018年第5期859-862,共4页
Spinocerebellar ataxias (SCAs) are a group of genetic disorders characterized by slowly progressive incoordina- tion of gait and are often associated with poor coordination of the hands, speech, and eye movements. F... Spinocerebellar ataxias (SCAs) are a group of genetic disorders characterized by slowly progressive incoordina- tion of gait and are often associated with poor coordination of the hands, speech, and eye movements. Frequently, atrophy of the cerebellum occurs. The genetic forms of ataxia are diagnosed by family history, physical examina- tion, neuroimaging, and molecular genetic testing. At present, 36 SCA subtypes including 27 pathogenic genes have been identified [1]. Different subtypes of SCAs have clear distribution differences among ethnic populations, and SCA8 is an infrequent entity worldwide, which has mostly been reported in Japanese, but has never been reported in Chinese [2]. SCAB involves bidirectional expression based on the total number of both the (CTA)n and (CTG)n expansion transcripts in ATXN8OS. The pathogenesis of this disorder is complex and the spectrum of clinical presentations is broad. It is predominantly characterized by drawn-out slowness of speech and gait instability, followed by slowly progressive ataxia, with disease onset typically occurring in adulthood [3]. How- ever, the lowest full-penetrance allele for SCA8 onset remains elusive and the current understanding of the phenotypic and genotypic features of SCA8 is limited. Since SCA8 has not yet been reported in the Chinese population and is scantily reported in a small proportion of pedigrees so far, clinical knowledge is still developing. Moreover, the boundary between the normal and patho- genic alleles of SCA8 is uncertain. Here we report the clinical and molecular genetic characteristics of 3 Chinese SCA8 families and have identified 51 CTA/CTG repeats within ATXN8OS, probably the shortest pathogenic allele for SCA8. 展开更多
关键词 CTG OS CTA Identification of Abnormal 51 CTA/CTG Expansion as probably the Shortest Pathogenic Allele for Spinocerebellar Ataxia-8 in China
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Probability Distribution Characteristics of Strong Nonlinear Waves Under Typhoon Conditions in the Northern South China Sea
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作者 GONG Yijie XIE Botao +2 位作者 FU Dianfu WANG Zhifeng PANG Liang 《Journal of Ocean University of China》 SCIE CAS CSCD 2024年第3期583-593,共11页
The generation and propagation mechanism of strong nonlinear waves in the South China Sea is an essential research area. In this study, the third-generation wave model WAVEWATCH Ⅲ is employed to simulate wave fields ... The generation and propagation mechanism of strong nonlinear waves in the South China Sea is an essential research area. In this study, the third-generation wave model WAVEWATCH Ⅲ is employed to simulate wave fields under extreme sea states. The model, integrating the ST6 source term, is validated against observed data, demonstrating its credibility. The spatial distribution of the occurrence probability of strong nonlinear waves during typhoons is shown, and the waves in the straits and the northeastern part of the South China Sea show strong nonlinear characteristics. The high-order spectral model HOS-ocean is employed to simulate the random wave surface series beneath five different platform areas. The waves during the typhoon exhibit strong nonlinear characteristics, and freak waves exist. The space-varying probability model is established to describe the short-term probability distribution of nonlinear wave series. The exceedance probability distributions of the wave surface beneath different platform areas are compared and analyzed. The results show that with an increase in the platform area, the probability of a strong nonlinear wave beneath the platform increases. 展开更多
关键词 strong nonlinear wave TYPHOON wave series probability distribution model exceedance probability
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Cr-induced fusion reactions to synthesize superheavy elements
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作者 S.Madhu H.C.Manjunatha +3 位作者 N.Sowmya B.M.Rajesh L.Seenappa R.S.Susheela 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第5期122-130,共9页
We investigated ^(50,52-54)Cr-induced fusion reactions for the synthesis of the superheavy element in the 104≤Z≤122 range.The cross sections produced in this investigation using ^(54)Cr projectiles were compared wit... We investigated ^(50,52-54)Cr-induced fusion reactions for the synthesis of the superheavy element in the 104≤Z≤122 range.The cross sections produced in this investigation using ^(54)Cr projectiles were compared with those obtained in prior experiments.The estimated cross sections from this analysis are consistent with the findings of prior studies.From the current study,the predicted cross section was found to be 42fb at 236 MeV for ^(53)Cr+^(243)Am,23.2 fb at 236 MeV for ^(54)Cr+^(247)Cm,95.6 fb at 240 MeV for ^(53)Cr+248Bk,and 1.33 fb at 242 MeV for ^(53)Cr+250Cf.Consequently,these projected cross sections with excitation energy and beam energy will be useful in future Cr-induced fusion reaction investigations. 展开更多
关键词 Fusion cross sections Compound nucleus formation probability Survival probability Evaporation residue cross sections
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Vulnerability assessment of UAV engine to laser based on improved shotline method
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作者 Le Liu Chengyang Xu +3 位作者 Changbin Zheng Sheng Cai Chunrui Wang Jin Guo 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第3期588-600,共13页
Laser anti-drone technology is entering the sequence of actual combat,and it is necessary to consider the vulnerability of typical functional parts of UAVs.Since the concept of"vulnerability"was proposed,a v... Laser anti-drone technology is entering the sequence of actual combat,and it is necessary to consider the vulnerability of typical functional parts of UAVs.Since the concept of"vulnerability"was proposed,a variety of analysis programs for battlefield targets to traditional weapons have been developed,but a comprehensive assessment methodology for targets'vulnerability to laser is still missing.Based on the shotline method,this paper proposes a method that equates laser beam to shotline array,an efficient vulnerability analysis program of target to laser is established by this method,and the program includes the circuit board and the wire into the vulnerability analysis category,which improves the precision of the vulnerability analysis.Taking the UAV engine part as the target of vulnerability analysis,combine with the"life-death unit method"to calculate the laser penetration rate of various materials of the UAV,and the influence of laser weapon system parameters and striking orientation on the killing probability is quantified after introducing the penetration rate into the vulnerability analysis program.The quantitative analysis method proposed in this paper has certain general expansibility,which can provide a fresh idea for the vulnerability analysis of other targets to laser. 展开更多
关键词 Laser weapon Laser damage VULNERABILITY UAV ENGINE Killing probability
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Distributed IRS-Aided DF Relaying Systems:Performance Analysis and Optimization
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作者 Sun Qiang Qian Panpan +3 位作者 Chen Xiaomin Ju Jinjuan Wang Jue Zhang Jiayi 《China Communications》 SCIE CSCD 2024年第6期129-145,共17页
Intelligent reflecting surface(IRS)is a newly emerged and promising paradigm to substantially improve the performance of wireless communications by constructing favorable communication channels via properly tuning mas... Intelligent reflecting surface(IRS)is a newly emerged and promising paradigm to substantially improve the performance of wireless communications by constructing favorable communication channels via properly tuning massive reflecting elements.This paper considers a distributed IRS aided decode-and-forward(DF)relaying system over Nakagami-m fading channels.Based on a tight approximation for the distribution of the received signalto-noise ratio(SNR),we first derive exact closed-form expressions of the outage probability,ergodic capacity,and energy efficiency for the considered system.Moreover,we propose the optimal IRS configuration considering the energy efficiency and pilot overhead.Finally,we compare the performance between the distributed IRS-aided DF relaying and multi-IRS-only systems,and verify the analytical results by using monte carlo simulations. 展开更多
关键词 CONFIGURATION energy efficiency ergodic capacity intelligent reflecting surface IRS outage probability
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A deep learning method based on prior knowledge with dual training for solving FPK equation
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作者 彭登辉 王神龙 黄元辰 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第1期250-263,共14页
The evolution of the probability density function of a stochastic dynamical system over time can be described by a Fokker–Planck–Kolmogorov(FPK) equation, the solution of which determines the distribution of macrosc... The evolution of the probability density function of a stochastic dynamical system over time can be described by a Fokker–Planck–Kolmogorov(FPK) equation, the solution of which determines the distribution of macroscopic variables in the stochastic dynamic system. Traditional methods for solving these equations often struggle with computational efficiency and scalability, particularly in high-dimensional contexts. To address these challenges, this paper proposes a novel deep learning method based on prior knowledge with dual training to solve the stationary FPK equations. Initially, the neural network is pre-trained through the prior knowledge obtained by Monte Carlo simulation(MCS). Subsequently, the second training phase incorporates the FPK differential operator into the loss function, while a supervisory term consisting of local maximum points is specifically included to mitigate the generation of zero solutions. This dual-training strategy not only expedites convergence but also enhances computational efficiency, making the method well-suited for high-dimensional systems. Numerical examples, including two different two-dimensional(2D), six-dimensional(6D), and eight-dimensional(8D) systems, are conducted to assess the efficacy of the proposed method. The results demonstrate robust performance in terms of both computational speed and accuracy for solving FPK equations in the first three systems. While the method is also applicable to high-dimensional systems, such as 8D, it should be noted that computational efficiency may be marginally compromised due to data volume constraints. 展开更多
关键词 deep learning prior knowledge FPK equation probability density function
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αDecay in extreme laser fields within a deformed Gamow-like model
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作者 Qiong Xiao Jun-Hao Cheng +3 位作者 Yang-Yang Xu You-Tian Zou Jun-Gang Deng Tong-Pu Yu 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第2期131-144,共14页
In this study, the effect of extreme laser fields on the α decay process of ground-state even–even nuclei was investigated.Using the deformed Gamow-like model, we found that state-of-the-art lasers can cause a sligh... In this study, the effect of extreme laser fields on the α decay process of ground-state even–even nuclei was investigated.Using the deformed Gamow-like model, we found that state-of-the-art lasers can cause a slight change in the α decay penetration probability of most nuclei. In addition, we studied the correlation between the rate of change of the α decay penetration probability and angle between the directions of the laser electric field and α particle emission for different nuclei. Based on this correlation, the average effect of extreme laser fields on the half-life of many nuclei with arbitrary α particle emission angles was calculated. The calculations show that the laser suppression and promotion effects on the α decay penetration probability of the nuclei population with completely random α particle-emission directions are not completely canceled.The remainder led to a change in the average penetration probability of the nuclei. Furthermore, the possibility of achieving a higher average rate of change by altering the spatial shape of the laser is explored. We conclude that circularly polarized lasers may be helpful in future experiments to achieve a more significant average rate of change of the α decay half-life of the nuclei population. 展开更多
关键词 αDecay Deformed Gamow-like model HALF-LIVES Extreme laser field Penetration probability
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A Game-Theoretic Approach to Safe Crowd Evacuation in Emergencies
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作者 Maria Gul Imran Ali Khan +9 位作者 Gohar Zaman Atta Rahman Jamaluddin Mir Sardar Asad Ali Biabani May IssaAldossary Mustafa Youldash Ashraf Saadeldeen Maqsood Mahmud Asiya Abdus Salam Dania Alkhulaifi 《Computers, Materials & Continua》 SCIE EI 2024年第4期1631-1657,共27页
Obstacle removal in crowd evacuation is critical to safety and the evacuation system efficiency. Recently, manyresearchers proposed game theoreticmodels to avoid and remove obstacles for crowd evacuation. Game theoret... Obstacle removal in crowd evacuation is critical to safety and the evacuation system efficiency. Recently, manyresearchers proposed game theoreticmodels to avoid and remove obstacles for crowd evacuation. Game theoreticalmodels aim to study and analyze the strategic behaviors of individuals within a crowd and their interactionsduring the evacuation. Game theoretical models have some limitations in the context of crowd evacuation. Thesemodels consider a group of individuals as homogeneous objects with the same goals, involve complex mathematicalformulation, and cannot model real-world scenarios such as panic, environmental information, crowds that movedynamically, etc. The proposed work presents a game theoretic model integrating an agent-based model to removethe obstacles from exits. The proposed model considered the parameters named: (1) obstacle size, length, andwidth, (2) removal time, (3) evacuation time, (4) crowd density, (5) obstacle identification, and (6) route selection.The proposed work conducts various experiments considering different conditions, such as obstacle types, obstacleremoval, and several obstacles. Evaluation results show the proposed model’s effectiveness compared with existingliterature in reducing the overall evacuation time, cell selection, and obstacle removal. The study is potentially usefulfor public safety situations such as emergency evacuations during disasters and calamities. 展开更多
关键词 Safe crowd evacuation public safety EMERGENCY transition probability COOPERATION
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Integrating host biological and ecological variables to predict probability of haemosporidian infection in raptors
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作者 Kai Gao Xuemei Yang +1 位作者 Xi Huang Wenhong Deng 《Avian Research》 SCIE CSCD 2024年第2期255-264,共10页
Variations in host traits that influence their exposure and susceptibility may impact probability of vector-transmitted diseases.Therefore,identifying the predictors of infection probability is necessary to understand... Variations in host traits that influence their exposure and susceptibility may impact probability of vector-transmitted diseases.Therefore,identifying the predictors of infection probability is necessary to understand the risk of disease outbreaks during expanding environmental perturbation.Here,we conducted a large survey based on microscopic examination and molecular analysis of haemosporidian parasite infection in raptors rescued at the Beijing Raptor Rescue Centre.Combining these data with biological and ecological variables of the raptors,we determined predictors that affect the probability of haemosporidian infection using generalized linear mixed models and multimodel inference.Our results showed that infection probability exhibited considerable variation across host species in raptors,and body mass,sex,and evolutionary history played relatively weaker roles in driving infection probability.Instead,activity pattern,age,geographic range size,migration distance,and nest type were important predictors of the probability of haemosporidian infection,and the role of each predictor differed in the three main haemosporidian genera(Plasmodium,Haemoproteus,and Leucocytozoon).This macro-ecological analysis will add to our understanding of host traits that influence the probability of avian haemosporidian infection and will help inform risk of emerging diseases. 展开更多
关键词 Activity pattern Emerging infectious diseases Infection probability Interspecific variation Migratory exposure
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Uncertainty quantification of mechanism motion based on coupled mechanism—motor dynamic model for ammunition delivery system
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作者 Jinsong Tang Linfang Qian +3 位作者 Longmiao Chen Guangsong Chen Mingming Wang Guangzu Zhou 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第3期125-133,共9页
In this paper,a dynamic modeling method of motor driven electromechanical system is presented,and the uncertainty quantification of mechanism motion is investigated based on this method.The main contribution is to pro... In this paper,a dynamic modeling method of motor driven electromechanical system is presented,and the uncertainty quantification of mechanism motion is investigated based on this method.The main contribution is to propose a novel mechanism-motor coupling dynamic modeling method,in which the relationship between mechanism motion and motor rotation is established according to the geometric coordination of the system.The advantages of this include establishing intuitive coupling between the mechanism and motor,facilitating the discussion for the influence of both mechanical and electrical parameters on the mechanism,and enabling dynamic simulation with controller to take the randomness of the electric load into account.Dynamic simulation considering feedback control of ammunition delivery system is carried out,and the feasibility of the model is verified experimentally.Based on probability density evolution theory,we comprehensively discuss the effects of system parameters on mechanism motion from the perspective of uncertainty quantization.Our work can not only provide guidance for engineering design of ammunition delivery mechanism,but also provide theoretical support for modeling and uncertainty quantification research of mechatronics system. 展开更多
关键词 Ammunition delivery system Electromechanical coupling dynamics Uncertainty quantification Generalized probability density evolution
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Locally and globally uniform approximations for ruin probabilities of a nonstandard bidimensional risk model with subexponential claims
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作者 LIU Zai-ming GENG Bing-zhen WANG Shi-jie 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2024年第1期98-113,共16页
Consider a nonstandard continuous-time bidimensional risk model with constant force of interest,in which the two classes of claims with subexponential distributions satisfy a general dependence structure and each pair... Consider a nonstandard continuous-time bidimensional risk model with constant force of interest,in which the two classes of claims with subexponential distributions satisfy a general dependence structure and each pair of the claim-inter-arrival times is arbitrarily dependent.Under some mild conditions,we achieve a locally uniform approximation of the finite-time ruin probability for all time horizon within a finite interval.If we further assume that each pair of the claim-inter-arrival times is negative quadrant dependent and the two classes of claims are consistently-varying-tailed,it shows that the above obtained approximation is also globally uniform for all time horizon within an infinite interval. 展开更多
关键词 bidimensional risk model asymptotic formula subexponential distribution consistently varying tail ruin probability
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On the Application of Mixed Models of Probability and Convex Set for Time-Variant Reliability Analysis
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作者 Fangyi Li Dachang Zhu Huimin Shi 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第5期1981-1999,共19页
In time-variant reliability problems,there are a lot of uncertain variables from different sources.Therefore,it is important to consider these uncertainties in engineering.In addition,time-variant reliability problems... In time-variant reliability problems,there are a lot of uncertain variables from different sources.Therefore,it is important to consider these uncertainties in engineering.In addition,time-variant reliability problems typically involve a complexmultilevel nested optimization problem,which can result in an enormous amount of computation.To this end,this paper studies the time-variant reliability evaluation of structures with stochastic and bounded uncertainties using a mixed probability and convex set model.In this method,the stochastic process of a limit-state function with mixed uncertain parameters is first discretized and then converted into a timeindependent reliability problem.Further,to solve the double nested optimization problem in hybrid reliability calculation,an efficient iterative scheme is designed in standard uncertainty space to determine the most probable point(MPP).The limit state function is linearized at these points,and an innovative random variable is defined to solve the equivalent static reliability analysis model.The effectiveness of the proposed method is verified by two benchmark numerical examples and a practical engineering problem. 展开更多
关键词 Mixed uncertainty probability model convex model time-variant reliability analysis
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High-dimensional uncertainty quantification of projectile motion in the barrel of a truck-mounted howitzer based on probability density evolution method
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作者 Mingming Wang Linfang Qian +3 位作者 Guangsong Chen Tong Lin Junfei Shi Shijie Zhou 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第2期209-221,共13页
This paper proposed an efficient research method for high-dimensional uncertainty quantification of projectile motion in the barrel of a truck-mounted howitzer.Firstly,the dynamic model of projectile motion is establi... This paper proposed an efficient research method for high-dimensional uncertainty quantification of projectile motion in the barrel of a truck-mounted howitzer.Firstly,the dynamic model of projectile motion is established considering the flexible deformation of the barrel and the interaction between the projectile and the barrel.Subsequently,the accuracy of the dynamic model is verified based on the external ballistic projectile attitude test platform.Furthermore,the probability density evolution method(PDEM)is developed to high-dimensional uncertainty quantification of projectile motion.The engineering example highlights the results of the proposed method are consistent with the results obtained by the Monte Carlo Simulation(MCS).Finally,the influence of parameter uncertainty on the projectile disturbance at muzzle under different working conditions is analyzed.The results show that the disturbance of the pitch angular,pitch angular velocity and pitch angular of velocity decreases with the increase of launching angle,and the random parameter ranges of both the projectile and coupling model have similar influence on the disturbance of projectile angular motion at muzzle. 展开更多
关键词 Truck-mounted howitzer Projectile motion Uncertainty quantification Probability density evolution method
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