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茶树STOP基因家族的鉴定及表达模式分析
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作者 龙露 汤丹丹 +3 位作者 陈玮 谭礼强 陈盛相 唐茜 《茶叶科学》 CAS CSCD 北大核心 2024年第3期386-398,共13页
STOP(Sensitive to proton rhizotoxicity)是一类C_(2)H_(2)型锌指结构转录因子,在植物多种胁迫耐受机制中发挥重要调控作用。基于茶树(Camellia sinensis)全基因组数据共鉴定出6个STOP家族基因,并运用生物信息学和实时荧光定量PCR(qRT-... STOP(Sensitive to proton rhizotoxicity)是一类C_(2)H_(2)型锌指结构转录因子,在植物多种胁迫耐受机制中发挥重要调控作用。基于茶树(Camellia sinensis)全基因组数据共鉴定出6个STOP家族基因,并运用生物信息学和实时荧光定量PCR(qRT-PCR)等方法对其进行分析。结果表明,6个CsSTOPs基因编码376~505个氨基酸,蛋白质分子量为42.17~56.36 kDa,理论等电点为5.53~8.85,均为不稳定蛋白;蛋白质保守结构域分析发现,它们均含zf-C_(2)H_(2)保守结构域;系统进化分析显示,茶树的STOP基因与拟南芥、甜橙、烟草的同源性较高;启动子顺式作用元件分析发现,CsSTOPs具有许多与生长发育、激素响应及非生物胁迫相关的作用元件;茶树各器官的转录组数据分析结果表明,CsSTOP1在根、果实、成熟叶片中的表达量较高,CsSTOP2在幼嫩叶片中的表达量较高,CsSTOP3在老叶中的表达量较高,而Cs STOP4和Cs STOP5在各个器官中的表达都较低。CsSTOPs基因能够被PEG诱导的干旱胁迫、盐胁迫、茉莉酸甲酯胁迫和冷胁迫处理诱导表达,说明CsSTOPs基因参与调控茶树生长发育和响应非生物胁迫过程。qRT-PCR检测发现,CsSTOPs、CsGS1s和CsGDHs基因在高NH_(4)^(+)浓度处理(4.5 mmol·L^(-1))的峨眉问春茶树叶和根中的表达量均高于对照处理(CK),尤其是叶中CsSTOPs、CsGS1.1、CsGS1.3和CsGDH2在高NH_(4)^(+)浓度处理下的表达量显著高于对照。研究结果初步解析了CsSTOPs的基本特征和功能,发现CsSTOPs可响应高NH_(4)^(+)浓度处理,可能与CsGS1s和CsGDHs协同调控茶树适应高NH_(4)^(+)环境的过程。 展开更多
关键词 茶树 stop基因家族 生物信息学分析 基因表达
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Effects of sequential decay on collective flows and nuclear stopping power in heavy-ion collisions at intermediate energies 被引量:1
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作者 Kui Xiao Peng-Cheng Li +2 位作者 Yong-Jia Wang Fu-Hu Liu Qing-Feng Li 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2023年第4期175-184,共10页
In this study, the rapidity distribution, collective flows, and nuclear stopping power in ^(197)Au+^(197)Au collisions at intermediate energies were investigated using the ultrarelativistic quantum molecular dynamics(... In this study, the rapidity distribution, collective flows, and nuclear stopping power in ^(197)Au+^(197)Au collisions at intermediate energies were investigated using the ultrarelativistic quantum molecular dynamics(UrQMD) model with GEMINI++ code. The UrQMD model was adopted to simulate the dynamic evolution of heavy-ion collisions, whereas the GEMINI++ code was used to simulate the decay of primary fragments produced by UrQMD. The calculated results were compared with the INDRA and FOPI experimental data. It was found that the rapidity distribution, collective flows, and nuclear stopping power were affected to a certain extent by the decay of primary fragments, especially at lower beam energies. Furthermore, the experimental data of the collective flows and nuclear stopping power at the investigated beam energies were better reproduced when the sequential decay effect was included. 展开更多
关键词 Heavy-ion collisions Sequential decay effect Collective flow Nuclear stopping power
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Analysis of Stopping Behavior at Rural T-Intersections Using Naturalistic Driving Study Data
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作者 Nicole Oneyear Shauna Hallmark +2 位作者 Amrita Goswamy Raju Thapa Guillermo Basulto-Elias 《Journal of Transportation Technologies》 2023年第2期208-221,共14页
Rural intersections account for around 30% of crashes in rural areas and 6% of all fatal crashes, representing a significant but poorly understood safety problem. Crashes at rural intersections are also problematic si... Rural intersections account for around 30% of crashes in rural areas and 6% of all fatal crashes, representing a significant but poorly understood safety problem. Crashes at rural intersections are also problematic since high speeds on intersection approaches are present which can exacerbate the impact of a crash. Additionally, rural areas are often underserved with EMS services which can further contribute to negative crash outcomes. This paper describes an analysis of driver stopping behavior at rural T-intersections using the SHRP 2 Naturalistic Driving Study data. Type of stop was used as a safety surrogate measure using full/rolling stops compared to non-stops. Time series traces were obtained for 157 drivers at 87 unique intersections resulting in 1277 samples at the stop controlled approach for T-intersections. Roadway (i.e. number of lanes, presence of skew, speed limit, presence of stop bar or other traffic control devices), driver (age, gender, speeding), and environmental characteristics (time of day, presence of rain) were reduced and included as independent variables. Results of a logistic regression model indicated drivers were less likely to stop during the nighttime. However presence of intersection lighting increased the likelihood of full/rolling stops. Presence of intersection skew was shown to negatively impact stopping behavior. Additionally drivers who were traveling over the posted speed limit upstream of the intersection approach were less likely to stop at the approach stop sign. 展开更多
关键词 Naturalistic Driving Study Data INTERSECTION Safety RURAL stopping Behavior
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Initial and Stopping Condition in Possibility Principal Factor Rotation
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作者 Houju Hori Jr. 《Journal of Applied Mathematics and Physics》 2023年第5期1482-1486,共5页
Uemura [1] discovered the mapping formula for Type 1 Vague events and presented an alternative problem as an example of its application. Since it is well known that the alternative problem leads to sequential Bayesian... Uemura [1] discovered the mapping formula for Type 1 Vague events and presented an alternative problem as an example of its application. Since it is well known that the alternative problem leads to sequential Bayesian inference, the flow of subsequent research was to make the mapping formula multidimensional, to introduce the concept of time, and to derive a Markov (decision) process. Furthermore, we formulated stochastic differential equations to derive them [2]. This paper refers to type 2 vague events based on a second-order mapping equation. This quadratic mapping formula gives a certain rotation named as possibility principal factor rotation by transforming a non-mapping function by a relation between two mapping functions. In addition, the derivation of the Type 2 Complex Markov process and the initial and stopping conditions in this rotation are mentioned. . 展开更多
关键词 Extension Principle Vague Event Type 2 Possibility Different Equation Possibility Principal Factor Analysis Initial and stopping Condition
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Multi-objective optimization design of anti-roll torsion bar using improved beluga whale optimization algorithm
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作者 Yonghua Li Zhe Chen +1 位作者 Maorui Hou Tao Guo 《Railway Sciences》 2024年第1期32-46,共15页
Purpose – This study aims to reduce the redundant weight of the anti-roll torsion bar brought by thetraditional empirical design and improving its strength and stiffness.Design/methodology/approach – Based on the fi... Purpose – This study aims to reduce the redundant weight of the anti-roll torsion bar brought by thetraditional empirical design and improving its strength and stiffness.Design/methodology/approach – Based on the finite element approach coupled with the improved belugawhale optimization (IBWO) algorithm, a collaborative optimization method is suggested to optimize the designof the anti-roll torsion bar structure and weight. The dimensions and material properties of the torsion bar weredefined as random variables, and the torsion bar’s mass and strength were investigated using finite elements.Then, chaotic mapping and differential evolution (DE) operators are introduced to improve the beluga whaleoptimization (BWO) algorithm and run case studies.Findings – The findings demonstrate that the IBWO has superior solution set distribution uniformity,convergence speed, solution correctness and stability than the BWO. The IBWO algorithm is used to optimizethe anti-roll torsion bar design. The error between the optimization and finite element simulation results wasless than 1%. The weight of the optimized anti-roll torsion bar was lessened by 4%, the maximum stress wasreduced by 35% and the stiffness was increased by 1.9%.Originality/value – The study provides a methodological reference for the simulation optimization process ofthe lateral anti-roll torsion bar. 展开更多
关键词 anti-roll torsion bar Multi-objective optimization IBWO Chaotic mapping Differential evolution
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改良STOP-BANG问卷对无痛胃镜检查低氧血症的预测价值
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作者 李坚 楼海斌 沈祝苹 《中国现代医生》 2024年第10期43-46,共4页
目的 探讨改良STOP-BANG问卷(modified STOP-BANG questionnaire,MSBQ)对无痛胃镜检查低氧血症的预测价值。方法 选取2021年10月至12月于浙江省肿瘤医院行无痛胃镜检查的300例患者为研究对象,检查前以MSBQ和STOP-BANG问卷(STOP-BANG que... 目的 探讨改良STOP-BANG问卷(modified STOP-BANG questionnaire,MSBQ)对无痛胃镜检查低氧血症的预测价值。方法 选取2021年10月至12月于浙江省肿瘤医院行无痛胃镜检查的300例患者为研究对象,检查前以MSBQ和STOP-BANG问卷(STOP-BANG questionnaire,SBQ)进行评估,根据评分将患者分为高风险组(总分≥3分)和低风险组(总分<3分)。观察两个量表高风险组和低风险组患者的低氧血症发生率,采用受试者操作特征曲线(receiver operating characteristic curve,ROC曲线)评估MSBQ和SBQ对无痛胃镜检查低氧血症风险的预测价值。结果 两个量表高风险组患者的低氧血症发生率均显著高于低风险组(P<0.05);MSBQ和SBQ预测无痛胃镜检查发生低氧血症的敏感度分别为81.01%、83.54%,特异性分别为78.28%、66.06%,曲线下面积分别为0.81、0.79,MSBQ的预测效能更好。结论 MSBQ对无痛胃镜检查低氧血症风险有较高的预测价值。 展开更多
关键词 改良stop-BANG问卷 无痛胃镜 低氧血症 风险 预测价值
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A Stylistic Analysis of “Stopping by Woods on a Snowy Evening”
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作者 刘颖 《中国校外教育》 2009年第S2期368-368,共1页
This paper gives a stylistic analysis of the poem "Stopping by Woods on a Snowy Evening" by American poet Robert Frost, and then probes how the author achieves his expected goal through attracting readers... This paper gives a stylistic analysis of the poem "Stopping by Woods on a Snowy Evening" by American poet Robert Frost, and then probes how the author achieves his expected goal through attracting readers' attention and leaving them much space to create their own imagination. 展开更多
关键词 STYLISTICS analysis "stopping by WOODS on a SNOWY
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硫族化合物非晶态薄膜波导optical-stopping效应研究
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作者 陈林 梁东波 +3 位作者 陈抱雪 浜中广见 袁一方 矶守 《上海第二工业大学学报》 2002年第2期1-6,共6页
本文通过实验对As2S8这种硫系非晶态材料的光学截止(optical-stopping)现象进行研究,报告了硫系非晶态As2S8薄膜波导的制备工艺,以及实验光路和光学截止现象的过程。并且结合了其它一些有关硫系非晶态半导体中的光诱起现象的报道,提出... 本文通过实验对As2S8这种硫系非晶态材料的光学截止(optical-stopping)现象进行研究,报告了硫系非晶态As2S8薄膜波导的制备工艺,以及实验光路和光学截止现象的过程。并且结合了其它一些有关硫系非晶态半导体中的光诱起现象的报道,提出了以微结构变动为前提、结合半导体能级理论的电子抽运模型,对实验现象进行了解释。 展开更多
关键词 硫族化合物 optical-stopping效应 光波导 非晶态As2S8薄膜 棱镜耦合 光学截止效应
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Ruling out small stopping sets and small girth in Tanner graph of QC-LDPC code 被引量:2
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作者 Lingjun Kong Yang Xiao 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2010年第1期134-137,共4页
The existing constructions of quasi-cyclic low-density parity-check (QC-LDPC) codes do not consider the problems of small stopping sets and small girth together in the Tanner graph, while their existences will lead ... The existing constructions of quasi-cyclic low-density parity-check (QC-LDPC) codes do not consider the problems of small stopping sets and small girth together in the Tanner graph, while their existences will lead to the bit error rate (BER) performance of QC-LDPC codes being much poorer than that of randomly constructed LDPC codes even decoding failure. To solve the problem, some theorems of the specific chosen parity-check matrix of QC-LDPC codes without small stopping sets and small girth are proposed. A novel construction for QC-LDPC codes with long block lengths is presented by multiplying mmin or the multiple of mmin, which is the minimum order of the identity matrix for the chosen parity-check matrix. The simulation results show that the specific chosen parity-check matrix of QC-LDPC codes can effectively avoid specified stopping sets and small girth and exhibit excellent BER performance than random LDPC codes with the same longer codes length. 展开更多
关键词 quasi-cyclic low-density parity-check codes stoppingset stopping distance GIRTH circulant matrices.
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FORWARD-BACKWARD STOCHASTIC DIFFERENTIAL EQUATIONS WITH STOPPING TIME 被引量:2
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作者 吴臻 《Acta Mathematica Scientia》 SCIE CSCD 2004年第1期91-99,共9页
The existence and uniqueness results of fully coupled forward-backward stochastic differential equations with stopping time (unbounded) is obtained. One kind of comparison theorem for this kind of equations is also pr... The existence and uniqueness results of fully coupled forward-backward stochastic differential equations with stopping time (unbounded) is obtained. One kind of comparison theorem for this kind of equations is also proved. 展开更多
关键词 Forward-backward stochastic differential equations stopping time comparison theorem
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Some Understanding of "Stopping by Woods on a Snowy Evening" by Robert Frost from Linguistic Point of View
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作者 端木红梅 《克拉玛依学刊》 2010年第2期251-252,共2页
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Research on the influence of action between fin and anti-rolling tank on the integrated stabilization effect 被引量:2
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作者 YU Li-jun JIN Hong-zhang WANG Hui YANG Sheng 《Journal of Marine Science and Application》 2007年第1期9-14,共6页
Through analyzing the roll model of the integrated system of fin and anti-rolling tank, this paper uses binomial equation to simplify the module and check how the approximate parameters simulate the original function.... Through analyzing the roll model of the integrated system of fin and anti-rolling tank, this paper uses binomial equation to simplify the module and check how the approximate parameters simulate the original function. Based on the simplified module, the influence of fin and anti-rolling tank on the coefficient items of the roll module is discussed, and the influencing factors between fin and anti-rolling tank are analysed. And through simulation, the influence of action between fin and anti-rolling tank on the static characteristics, and the integrated stabilization effect, are analyzed. 展开更多
关键词 fin stabilizer anti-rolling tank integrated stabilization action each other INFLUENCE
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STUDY ON VARIATION OF SETTING AND STOPPING PRESSURES OF SAFETY VALVE WITH STRUCTURAL MODIFICATION 被引量:1
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作者 Lee Jinho Kwangzin Valve Industrial Co ,Ltd,Korea Kim Harkbong Kim Moonsang School of Aerospace and Mechanical Engineering,Hankook Aviation University,Korea 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2001年第2期127-138,共12页
The possibility of pressure control with the structural change of a safety valve is investigated Safety valve is commonly used as safety devices for numerous applications which include boilers,ships,industrial plant... The possibility of pressure control with the structural change of a safety valve is investigated Safety valve is commonly used as safety devices for numerous applications which include boilers,ships,industrial plants,and piping Setting and stopping pressures of a safety valve, p set and p sto ,are traditionally adjusted with a fine tuning of seat ring and valve ring heights, h sr and h vr However, it is not easy to achieve the proper setting and stopping pressures of a safety valve in practice The depth of inside and outside grooves in a valve, d i and d o are modified and their effects on setting and stopping pressures of a safety vlave are tested The most appropriate values appear 1 0 mm in d i and 0 5~1 0 mm in d o,respectively The valve ring height, h vr ,shows that the best results can be achieved at 2 3 mm for setting pressures of 0 1~0 4 MPa and 1 0 mm for setting pressures of 0 5~1 0 MPa The stopping pressures increases with the increase of seat ring height, h sr , upto certain h sr value and then becomes independent to the seat ring height This implies that there exists the optimum h sr ,which provides the largest flow rate and the proper stopping pressure Stopping pressures of a safety valve are adjusted with the seat ring and valve ring heights This study,however,demonstrated that the modification of value grooves also changes setting and stopping pressures of a safety valve Therefore,the proper selection in dimensions of the inside and outside grooves should be considered for the safety valve design 展开更多
关键词 Safety valve Compressive flow Isentropic flow theory Isentropic comressibility theory Setting pressure stopping pressure Continuity equation Momentum equation
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Ion stopping in dense plasmas: A basic physics approach 被引量:4
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作者 Claude Deutsch Gilles Maynard 《Matter and Radiation at Extremes》 SCIE EI CAS 2016年第6期277-307,共31页
We survey quite extensively the present research status of ion-stopping in dense plasmas of potential importance for initial confinement fusion(ICF)drivenby intense and heavy ion beams,and alsofor warm dense matter(WD... We survey quite extensively the present research status of ion-stopping in dense plasmas of potential importance for initial confinement fusion(ICF)drivenby intense and heavy ion beams,and alsofor warm dense matter(WDM).First,we putemphasis on every possible mechanism involved in the shaping of the ion projectile effective charge,while losing energy in a target plasma with classical ions and partially degenerate electrons.Then,we switch to ion stopping by target bound electrons,taking detailed account of mean excitation energies.Free electron stopping has already been given a lot of attention in former works[C.Deutsch et al.,Recent Res.Devel.Plasma 1(2000)1-23;Open Plasma Phys.J.3(2010)88-115].Then,we extend the usual standard stopping model(SSM)framework to nonlinear stopping including a treatment of the Z 3 Barkas effect and a confronting comparison of Bloch and Bohr Coulomb logarithms.Finally,we document low velocity ion slowing down(LVISD)in single ion plasmas as well as in binary ionic mixtures(BIM),in connection with specific ICF fuels. 展开更多
关键词 Ion projectile effective charge Mean excited energies Nonlinear stopping Binary ionic mixture
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Probing neutron–proton effective mass splitting using nuclear stopping and isospin mix in heavy-ion collisions in GeV energy region 被引量:3
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作者 Fan Zhang Jun Su 《Nuclear Science and Techniques》 SCIE CAS CSCD 2020年第8期35-42,共8页
The ramifications of the effective mass splitting on the nuclear stopping and isospin tracer during heavy-ion collisions within the gigaelectron volt energy region are studied using an isospin-dependent quantum molecu... The ramifications of the effective mass splitting on the nuclear stopping and isospin tracer during heavy-ion collisions within the gigaelectron volt energy region are studied using an isospin-dependent quantum molecular dynamics model.Three isotope probes,i.e.,a proton,deuteron,and triton,are used to calculate the nuclear stopping.Compared to the mn*>mp*case,the mn*<mp*parameter results in a stronger stopping for protons but a weaker stopping for tritons.The calculations of the isospin tracer show that the mn*>mp*parameter results in a higher isospin mix than the mn*<mp*parameter.The rapidity and impact parameter dependences of the isospin tracer are also studied.A constraining of the effective mass splitting using the free nucleons with high rapidity and in a central rather than peripheral collision is suggested. 展开更多
关键词 Neutron–proton effective mass splitting Nuclear stopping Isospin mix
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Energy Efficiency Maximization Strategy for Sink Node in SWIPT-Enabled Sensor-Cloud Based on Optimal Stopping Rules 被引量:2
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作者 Zhe Wang Lina Ge +2 位作者 Taoshen Li Guifen Zhang Min Wu 《China Communications》 SCIE CSCD 2021年第1期222-236,共15页
Leveraging energy harvesting abilities in wireless network devices has emerged as an effective way to prolong the lifetime of energy constrained systems.The system gains are usually optimized by designing resource all... Leveraging energy harvesting abilities in wireless network devices has emerged as an effective way to prolong the lifetime of energy constrained systems.The system gains are usually optimized by designing resource allocation algorithm appropriately.However,few works focus on the interaction that channel’s time-vary characters make the energy transfer inefficiently.To address this,we propose a novel system operation sequence for sensor-cloud system where the Sinks provide SWIPT for sensor nodes opportunistically during downlink phase and collect the data transmitted from sensor nodes in uplink phase.Then,the energy-efficiency maximization problem of the Sinks is presented by considering the time costs and energy consumption of channel detection.It is proved that the formulated problem is an optimal stopping process with optimal stopping rules.An optimal energy-efficiency(OEE)algorithm is designed to obtain the optimal stopping rules for SWIPT.Finally,the simulations are performed based on the OEE algorithm compared with the other two strategies to verify the effectiveness and gains in improving the system efficiency. 展开更多
关键词 sensor-cloud SWIPT optimal stopping theory energy efficiency channel quality
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ON SOLUTIONS OF BACKWARD STOCHASTIC DIFFERENTIAL EQUATIONS WITH JUMPS,WITH UNBOUNDED STOPPING TIMES AS TERMINAL AND WITH NON-LIPSCHITZ COEFFICIENTS,AND PROBABILISTIC INTERPRETATION OF QUASI-LINEAR ELLIPTIC TYPE INTEGRO-DIFFERENTIAL EQUATIO 被引量:1
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作者 司徒荣 王越平 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2000年第6期659-672,共14页
The existence and uniqueness of solutions to backward stochastic differential equations with jumps and with unbounded stopping time as terminal under the non_Lipschitz condition are obtained. The convergence of soluti... The existence and uniqueness of solutions to backward stochastic differential equations with jumps and with unbounded stopping time as terminal under the non_Lipschitz condition are obtained. The convergence of solutions and the continuous dependence of solutions on parameters are also derived. Then the probabilistic interpretation of solutions to some kinds of quasi_linear elliptic type integro_differential equations is obtained. 展开更多
关键词 backward stochastic differential equations(BSDEs) with jumps unbounded stopping time adapted solutions convergence of solutions quasi_linear elliptic equations integro_differential operators.
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Reasonable location of stopping line in close‑distance underlying coal seam and partition support of large cross‑section roadway 被引量:2
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作者 Dongdong Chen Yiyi Wu +3 位作者 Shengrong Xie Fangfang Guo Fulian He Ruipeng Liu 《International Journal of Coal Science & Technology》 EI CAS CSCD 2022年第4期181-202,共22页
Close-distance coal seams are widely distributed over China,and the coal pillars left by the overlying coal seams afect the retracement channel of the underlying coal seam in the stopping stage.Based on the engineerin... Close-distance coal seams are widely distributed over China,and the coal pillars left by the overlying coal seams afect the retracement channel of the underlying coal seam in the stopping stage.Based on the engineering background of close-distance seam mining in a coal mine,the reasonable position of the underlying coal seam's stopping line and the support method of the large section roadway during stopping are investigated using feld measurements,similar simulation experiments,and numerical simulations.There are three types of location relationships between the stopping line of the underlying coal seam and the stopping line of the overlying coal seam:"externally staggered with the upper stopping line"(ESUL,stops mining under the overlying goaf),"overlapped with upper stopping line"(OUL),and"internally staggered with the upper stopping line"(ISUL,ISUL-SD for shorter internal staggered distances,ISUL-LD for longer ones).There are diferent stress arch structures in the overlying strata of the above three positions,and the stress arch evolution process exists in the process of ESUL→OUL→ISUL-SD→ISUL-LD:a front and rear double stress arch structure→the front arch gradually decreases→the front arch dies out,and the double arch synthesizes the single arch→the single-arch range expands→the nested double arch.The relationship between the stress arch structure and the position of the stopping line is evaluated as follows:(1)ESUL:the stress concentration in the roof plate of the retracement channel of the underlying coal seam is the highest,because the overburden block of the extensive collapse zone acts directly on the roof plate of the retracement channel,resulting in relative difculties in roof support.(2)OUL:although the retracement channel roof pressure is minimal,the overlying rock structure has the potential for rotation or slippage instability.(3)ISUL-SD:the pressure on the roof of the retracement channel is small and the overburden structure is stable,which is conducive to the safe retraction of the support and not limited by the width of the end-mining coal pillar.(4)ISUL-LD:it is basically the same as the condition of stopping under the non-goaf;however,it has a limitation on the width of the end-mining coal pillar.The location of the stopping line is selected as ISUL-SD,and the retraction process of the self-excavating retraction channel was adopted.A partition asymmetric support scheme which is proven by feld practice is proposed,through a comprehensive analysis of the pre-stress feld simulation of the support scheme,based on the diferent control requirements of the roof above the support and the roof of the retracement channel in the stopping area.This method realizes safe and smooth withdrawal of the support. 展开更多
关键词 Close-distance coal seams stopping line Stress arch structure Retracement channel Partition support
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Mass Stopping Power and Range of Protons in Biological Human Body Tissues (Ovary, Lung and Breast) 被引量:1
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作者 Ahlam S. Almutairi Khalda T. Osman 《International Journal of Medical Physics, Clinical Engineering and Radiation Oncology》 2022年第1期48-59,共12页
In this work, the mass stopping power and range of protons in biological human body tissues (ovary, lung and breast) were calculated at the energy ranging from 0.04 MeV to 200 MeV using the MATLAB Program. The data re... In this work, the mass stopping power and range of protons in biological human body tissues (ovary, lung and breast) were calculated at the energy ranging from 0.04 MeV to 200 MeV using the MATLAB Program. The data relating to the densities, average atomic number to mass number  and excitation energy for the present tissues were collected from ICRU Report 46. The mass stopping power was calculated by the Bethe formula. Moreover, the simple integration (continuous slowing down approximation) method was employed for calculating protons range at the tissues. The results of the mass stopping power versus energy and the range versus energy were presented graphically and the empirical formulae for calculating the mass stopping power and the ranges were obtained. The present results for mass stopping powers and ranges were compared with the results obtained by others. Good agreements were found between them, especially at the energy ranging from 3 to 200 MeV. 展开更多
关键词 Human Body Tissues PROTONS RANGE MATLAB Mass stopping Power
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Optimal Stopping Time to Buy an Asset When Growth Rate Is a Two-State Markov Chain 被引量:1
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作者 Pham Van Khanh 《American Journal of Operations Research》 2014年第3期132-141,共10页
In this paper we consider the problem of determining the optimal time to buy an asset in a position of an uptrend or downtrend in the financial market and currency market as well as other markets. Asset price is model... In this paper we consider the problem of determining the optimal time to buy an asset in a position of an uptrend or downtrend in the financial market and currency market as well as other markets. Asset price is modeled as a geometric Brownian motion with drift being a two-state Markov chain. Based on observations of asset prices, investors want to detect the change points of price trends as accurately as possible, so that they can make the decision to buy. Using filtering techniques and stochastic analysis, we will develop the optimal boundary at which investors implement their decisions when the posterior probability process reaches a certain threshold. 展开更多
关键词 Optimal stopping Time POSTERIOR PROBABILITY THRESHOLD
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