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The Relevant Analysis on the Stop Time in Winter and Times of Plateau and the Index in Early Days for Garrisonned Plateau Constructors
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作者 Yuan Zhencai Zhang Xuefeng +3 位作者 Deng Yunqing Wu Chengkui Cao Ruiling Peng Quansheng 《工程科学(英文版)》 2007年第1期45-48,共4页
Objective: Study the influence of the stop time in winter, times of plateau on the index in early days for plateau constructors meet;Method:Is it participate in plateau construction of 2002-2004 to choose,enter into t... Objective: Study the influence of the stop time in winter, times of plateau on the index in early days for plateau constructors meet;Method:Is it participate in plateau construction of 2002-2004 to choose,enter into the plateau again of 2003-2005 practise clothes finish to mate 326 materials “physical examination in front of the worker",which is passed in Nanshankou Hospital in early days, divided into 3 groups according to the difference of year for the physical examination, examine by leaning towards relevant analytical methods;Result: (1) In the situation of day controlling about the stop time in winter, times of garrison in plateau and blood and oxygen saturation lever (SaO2), the systolic pressure (sBP) is presented and shouldered relevantly winter to control. Present positive correlation with the value of hemoglobin (Hb);(2) It is stopped that in case of controlling and is garrisoned in the number of times of plateau in winter day and blood and oxygen saturation lever (SaO2) to present positive correlation. Present and shoulder with the hemoglobin (Hb) relevantly.Conclusion: In order to ensure the health of plateau constructors to the maximum extent, should try one’s best to reduce the number of times of returning to the plateau in possible cases. At the same time each one constructs for year and returns to the time that the hinterland concentrates rest should be on above 90 days. 展开更多
关键词 re-entering the PLATEAU stop time in WINTER practice the CLOTHES relevant
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Optimization of transit total bus stop time models 被引量:6
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作者 Stephen Arhin Errol Noel +3 位作者 Melissa F.Anderson Lakeasha Williams Asteway Ribisso Regis Stinson 《Journal of Traffic and Transportation Engineering(English Edition)》 2016年第2期146-153,共8页
Several factors influence bus transit reliability which includes bus stop conditions along the route, traffic conditions, route of travel and time of day. The overall transit bus reli- ability is generally affected by... Several factors influence bus transit reliability which includes bus stop conditions along the route, traffic conditions, route of travel and time of day. The overall transit bus reli- ability is generally affected by dwell time (DT), the fare payment method, the bus stop location, and the number of passengers alighting or boarding. A new variable is defined in this study, total bus stop time (TBST), which is the summation of DT and the time it takes a bus to effectively park at a bus stop and the re-entering the traffic stream. It is suggested that the overall bus transit reliability along routes could be improved if the TBST is mini- mized at bus stops. In this study, TBST models for bus stops located at mid-blocks and near intersections were developed based on multivariate regression analysis using ordinary least squares method. Data collection was conducted at 60 bus stops, 30 of which were near intersections and 30 at mid-blocks, in Washington DC during morning, mid-day and evening peak hours. The variables observed at each bus stop are as follows: number of passengers alighting or boarding, DT, TBST, bus stop type, bus pad, length number of lanes on approach to the bus stop, and permitted parking. Statistical inferences were based on 5% level of significance. From the results, it was inferred that the new variable, TBST, could potentially be used to improve scheduling and transit bus systems planning in a dense urban area. 展开更多
关键词 Total bus stop time Dwell time Optimization Transit reliability Bus transit
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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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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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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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Waiting times and stopping probabilities for patterns in Markov chains
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作者 ZHAO Min-zhi XU Dong ZHANG Hui-zeng 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2018年第1期25-34,共10页
Suppose that C is a finite collection of patterns. Observe a Markov chain until one of the patterns in C occurs as a run. This time is denoted by τ. In this paper, we aim to give an easy way to calculate the mean wai... Suppose that C is a finite collection of patterns. Observe a Markov chain until one of the patterns in C occurs as a run. This time is denoted by τ. In this paper, we aim to give an easy way to calculate the mean waiting time E(τ) and the stopping probabilities P(τ = τA)with A ∈ C, where τA is the waiting time until the pattern A appears as a run. 展开更多
关键词 PATTERN Markov chain stopping probability waiting time
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The Optimal Stopping Time for Selling an Asset When It Is Uncertain Whether the Price Process Is Increasing or Decreasing When the Horizon Is Infinite
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作者 Nguyen Khac Minh Nguyen Thanh Trung Pham Van Khanh 《American Journal of Operations Research》 2018年第2期82-91,共10页
Assume that we want to shell an asset with unknown drift but known that the drift is a two value random variable, and the initial distribution can be estimated. As time goes by, this distribution is updated and base o... Assume that we want to shell an asset with unknown drift but known that the drift is a two value random variable, and the initial distribution can be estimated. As time goes by, this distribution is updated and base on the probability of the drift takes the small one gives us the stopping rule. Research results show that the optimal strategy to sell the asset is if the initial probability that the drift receives a small value greater than a certain threshold then liquidates the asset immediately, otherwise the asset holder will wait until the probability of the drift receives a small value passing a certain threshold, it is the optimal time to liquidate the asset. 展开更多
关键词 Optimal stopPING time Incomplete Information Probability PROCESS
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Optimal Stopping Time for Holding an Asset
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作者 Pham Van Khanh 《American Journal of Operations Research》 2012年第4期527-535,共9页
In this paper, we consider the problem to determine the optimal time to sell an asset that its price conforms to the Black-Schole model but its drift is a discrete random variable taking one of two given values and th... In this paper, we consider the problem to determine the optimal time to sell an asset that its price conforms to the Black-Schole model but its drift is a discrete random variable taking one of two given values and this probability distribution behavior changes chronologically. The result of finding the optimal strategy to sell the asset is the first time asset price falling into deterministic time-dependent boundary. Moreover, the boundary is represented by an increasing and continuous monotone function satisfying a nonlinear integral equation. We also conduct to find the empirical optimization boundary and simulate the asset price process. 展开更多
关键词 Optimal stopPING time BOUNDARY BROWNIAN Motion Black-Schole Model
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Nothing Lasts Forever Time to stop pining for authentic hutongs
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作者 Ellen Laughton 《ChinAfrica》 2015年第3期60-60,共1页
AS a foreigner anywhere, it is important to make an effort to experience the cultural heritage of the city you are in. In Paris you should visit Montmartre, in London you can't miss Buckingham Palace, and before you ... AS a foreigner anywhere, it is important to make an effort to experience the cultural heritage of the city you are in. In Paris you should visit Montmartre, in London you can't miss Buckingham Palace, and before you leave Sydney, a trip to the Blue Mountains is essential, For Beiiing, the unquestionable birthplace of Chinese culture is buried deep within the city's ancient hutongs. 展开更多
关键词 Nothing Lasts Forever time to stop pining for authentic hutongs
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基于CiteSpace的公交停靠时间影响因素分析
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作者 张旭 李亚平 +1 位作者 王伟强 李英帅 《物流科技》 2024年第4期77-83,102,共8页
为了降低公交停靠时的延误,以便于合理地进行公交站规划设计。通过利用CiteSpace对公交停靠时间领域文献进行研究。根据得到的图谱对当前的研究热点和以后的研究方向进行总结分析。结果表明,我国对公交停靠时间的研究可分为两个阶段,探... 为了降低公交停靠时的延误,以便于合理地进行公交站规划设计。通过利用CiteSpace对公交停靠时间领域文献进行研究。根据得到的图谱对当前的研究热点和以后的研究方向进行总结分析。结果表明,我国对公交停靠时间的研究可分为两个阶段,探索发展和钻研创新阶段,而近期研究热点偏向遗传算法和智能交通方向。精读文献后得出影响公交停靠时间的因素为乘客上下车时间和公交车加减速时间,同时结合站台形式这个特殊的影响因素进行了分类分析,为今后的公交停靠站设计提供参考。 展开更多
关键词 交通运输 停靠时间 影响因素 CITESPACE 可视化
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一站式预住院服务模式在肿瘤化疗患者中的应用实践
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作者 孙美花 易珊珊 +2 位作者 黄芳芳 李庆玲 黎云霞 《中国当代医药》 CAS 2024年第8期47-50,34,共5页
目的探讨一站式预住院服务模式在肿瘤化疗患者中的应用实践。方法选取江西省人民医院肿瘤科2023年1月至6月收治的180例恶性肿瘤化疗患者作为研究对象,按照随机数字表法将患者分为对照组(90例)和观察组(90例)。对照组采用常规方法办理住... 目的探讨一站式预住院服务模式在肿瘤化疗患者中的应用实践。方法选取江西省人民医院肿瘤科2023年1月至6月收治的180例恶性肿瘤化疗患者作为研究对象,按照随机数字表法将患者分为对照组(90例)和观察组(90例)。对照组采用常规方法办理住院手续,观察组采用一站式预住院方法办理住院手续。比较两组患者办理入院手续耗时、治疗前的完成检查时间、住院天数、住院费用、病区护士接待新入院患者的护理耗时、患者在病区和检查科室之间的往返次数和患者满意度情况。结果观察组患者办理入院手续的耗时、治疗前的完成检查时间、住院天数短于对照组,差异有统计学意义(P<0.05)。观察组患者住院费用低于对照组,差异有统计学意义(P<0.05)。病区护士接待新入院观察组患者的护理耗时短于对照组,差异有统计学意义(P<0.05)。观察组患者在病区和检查科室之间的往返次数少于对照组,差异有统计学意义(P<0.05)。观察组患者住院治疗后的满意率为95.56%,高于对照组的87.78%,差异有统计学意义(P<0.05)。结论一站式预住院服务模式能有效缩短患者办理入院手续耗时,缩短治疗前的完成检查时间和住院天数,降低住院费用,缩短病区护士接待新入院患者的护理耗时,减少患者在病区和检查科室之间的往返次数,提高患者满意度,值得在临床进一步推广。 展开更多
关键词 一站式预住院 完成检查时间 住院天数 住院费用 患者满意度
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具有未知时变参数城轨列车的精准停车鲁棒控制
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作者 李茂青 朱胜杰 +2 位作者 林俊亭 高云波 岳丽丽 《铁道学报》 EI CAS CSCD 北大核心 2024年第7期65-72,共8页
列车运行情况复杂多变,使得列车质量、基本运行阻力及线路状况等参数难以精确获得且随着列车运行存在明显的时变特性。列车模型参数的不确定性和时变特性会对列车的精准停车性能产生重要的影响。在动车组多质点动力学模型的基础上,根据L... 列车运行情况复杂多变,使得列车质量、基本运行阻力及线路状况等参数难以精确获得且随着列车运行存在明显的时变特性。列车模型参数的不确定性和时变特性会对列车的精准停车性能产生重要的影响。在动车组多质点动力学模型的基础上,根据Lyapunov再设计方法设计了一种非线性列车鲁棒控制器。该控制器将系统中的不确定性因素视为等价干扰,并设计相应的鲁棒补偿项。根据参数的先验区间,设计的鲁棒补偿项能够抑制模型估计误差,使得列车的位置和速度跟踪误差快速收敛,最终实现精准停车的控制目标;同时,也证明了系统的最终一致有界稳定性。最后,选取城市轨道交通场景进行仿真验证,仿真结果表明:本文提出的控制方法在列车模型参数未知且时变情景下也能实现对期望停车曲线的快速、精确追踪,表现出较强的鲁棒特性。 展开更多
关键词 列车自动运行 多质点模型 精准停车 鲁棒控制 未知时变参数 最终一致稳定性
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静停时间对长江下游蒸养疏浚砂浆特性的影响
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作者 吴朝国 陈徐东 +2 位作者 宁英杰 张伟 冯璐 《土木与环境工程学报(中英文)》 CSCD 北大核心 2024年第4期193-201,共9页
长江下游航道疏浚产生大量疏浚砂,疏浚砂的资源化利用受到重视。利用疏浚砂部分取代机制砂制备砂浆,研究不同静停时间对疏浚砂砂浆特性的影响,测试不同龄期的抗压强度,通过X射线衍射、扫描电镜、压汞技术,分析不同静停时间、不同疏浚砂... 长江下游航道疏浚产生大量疏浚砂,疏浚砂的资源化利用受到重视。利用疏浚砂部分取代机制砂制备砂浆,研究不同静停时间对疏浚砂砂浆特性的影响,测试不同龄期的抗压强度,通过X射线衍射、扫描电镜、压汞技术,分析不同静停时间、不同疏浚砂取代率砂浆的微观特性。结果表明:随着静停时间的增加,90 d抗压强度逐渐增加,抗渗性能得到明显改善;掺入疏浚砂使得砂浆的抗压强度有所提高,且随疏浚砂取代率的增加先增大后减小;疏浚砂砂浆的抗压强度与疏浚砂取代率有较大关系,其影响程度与静停时间有关,疏浚砂对低静停时间有较突出的增强效果;疏浚砂有效改善了由蒸养造成的孔结构粗化和孔隙增大等问题,适宜的疏浚砂取代率对蒸养砂浆性能的改善效果明显。 展开更多
关键词 疏浚砂 超细砂 砂浆 静停时间 力学性能 微观结构
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基于元胞自动机的航站楼离港车道边停车容量评估研究
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作者 张龙财 刘斌 +1 位作者 徐健平 刘明辉 《信息技术》 2024年第4期70-75,共6页
航站楼车道边是旅客实现陆空转换的关键节点,其规模对陆侧交通的正常运行有着至关重要的作用。针对航站楼离港车道边送客车辆的个体行为,基于元胞自动机提出一种改进型离港车道边停车容量仿真模型并利用实测数据对模型的准确性进行验证... 航站楼车道边是旅客实现陆空转换的关键节点,其规模对陆侧交通的正常运行有着至关重要的作用。针对航站楼离港车道边送客车辆的个体行为,基于元胞自动机提出一种改进型离港车道边停车容量仿真模型并利用实测数据对模型的准确性进行验证,最后利用文中模型分析了不同停车方式及停靠时间对停车容量的影响。试验结果表明,仿真结果与实测数据基本一致,可用于评估离港车道边停车容量;在车道边规模不变的前提下,竖向停车方式可以显著增加车道边停车容量;两种停车方式的车道边停车容量都随停靠时间的增加而减小。 展开更多
关键词 航站楼离港车道边 停车容量 元胞自动机 停车方式 停靠时间
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韵母类型对听障儿童不同塞音嗓音起始时间的影响
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作者 高雍象 吴迪 +4 位作者 冯岩 冯叶 王佳汝 余英 田成华 《听力学及言语疾病杂志》 CAS CSCD 北大核心 2024年第1期38-42,共5页
目的探究韵母类型对听障儿童不同塞音嗓音起始时间(voice onset time,VOT)的影响,为其塞音习得及矫正提供依据。方法随机选取3~6岁听障儿童和健听儿童各22例,录制6个塞音(/b/、/p/、/d/、/t/、/g/、/h/)与3个单韵母(/a/、/i/或/e/、/u/... 目的探究韵母类型对听障儿童不同塞音嗓音起始时间(voice onset time,VOT)的影响,为其塞音习得及矫正提供依据。方法随机选取3~6岁听障儿童和健听儿童各22例,录制6个塞音(/b/、/p/、/d/、/t/、/g/、/h/)与3个单韵母(/a/、/i/或/e/、/u/)所组成的18个辅-元(consonant-vowel,CV)音节,声调均为第一声。使用Praat 6.1.29软件提取VOT值,对每种塞音采用双因素方差分析,因变量为VOT,自变量为听力状况、韵母类型。结果听障组儿童/t/、/g/、/k/发音存在构音错误。听力状况对塞音/g/、/p/、/t/、/k/主效应效果显著(P<0.05),健听组塞音/g/、/p/、/t/、/k/的VOT显著大于听障组(P<0.05)。韵母类型对塞音/b/、/p/、/t/VOT主效应效果显著(P<0.05)。听力状况与韵母类型在塞音/t/VOT上产生交互效应,简单主效应显示,听障组与健听组/ti/音VOT差异大于/ta/及/tu/。结论听障儿童塞音/g/、/p/、/t/、/k/音的VOT小于健听儿童,听障组与健听组/ti/音的VOT差异大于/ta/及/tu/。对听障儿童/t/音教学,可以先从差异较小的/ta/、/tu/开始,后期巩固/ti/音,并且注重呼吸及口部运动训练,为清晰发音奠定良好的基础。 展开更多
关键词 嗓音起始时间 塞音 韵母 听障儿童
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Zero-Sum Continuous-Time Markov Games with One-Side Stopping
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作者 Yurii Averboukh 《Journal of the Operations Research Society of China》 EI CSCD 2024年第1期169-187,共19页
The paper is concerned with a variant of the continuous-time finite state Markov game of control and stopping where both players can affect transition rates,while only one player can choose a stopping time.The dynamic... The paper is concerned with a variant of the continuous-time finite state Markov game of control and stopping where both players can affect transition rates,while only one player can choose a stopping time.The dynamic programming principle reduces this problem to a system of ODEs with unilateral constraints.This system plays the role of the Bellman equation.We show that its solution provides the optimal strategies of the players.Additionally,the existence and uniqueness theorem for the deduced system of ODEs with unilateral constraints is derived. 展开更多
关键词 Continuous-time Markov games Dynamic programming Verification theorem stopping time
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内镜下不同钛夹封闭时间对NVUGIB患者止血有效率及再出血率的影响
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作者 兰春梅 李煜 +1 位作者 郑天翔 涂建军 《检验医学与临床》 CAS 2024年第13期1960-1963,共4页
目的探讨内镜下不同钛夹封闭时间对非静脉曲张性上消化道出血(NVUGIB)止血有效率及再出血率的影响。方法选回顾性选取2020年3月到2023年3月福建省南平市邵武市立医院收治的96例NVUGIB患者为研究对象,根据内镜下钛夹封闭时间分为早期组(5... 目的探讨内镜下不同钛夹封闭时间对非静脉曲张性上消化道出血(NVUGIB)止血有效率及再出血率的影响。方法选回顾性选取2020年3月到2023年3月福建省南平市邵武市立医院收治的96例NVUGIB患者为研究对象,根据内镜下钛夹封闭时间分为早期组(50例,入院后6~<12 h进行治疗)及常规组(46例,入院后12~24 h进行治疗)。比较两组治疗后止血有效率、治疗前后免疫因子水平、治疗后再出血率。结果治疗后,早期组止血有效率为98.00%,明显高于常规组的82.61%,差异有统计学意义(χ^(2)=4.991,P=0.025)。治疗前,两组CD3^(+)、CD4^(+)、NK细胞水平比较,差异均无统计学意义(P>0.05)。治疗后,两组CD3^(+)、CD4^(+)、NK细胞水平均高于治疗前,且早期组均高于常规组,差异均有统计学意义(P<0.05)。治疗后,早期组总再出血率为4.00%,低于常规组的21.74%,差异有统计学意义(χ^(2)=6.892,P=0.008)。结论入院后6~<12 h内对NVUGIB患者进行内镜下钛夹封闭能有效提高NVUGIB止血有效率,改善患者免疫功能,降低再出血发生率,有利于改善患者预后。 展开更多
关键词 非静脉曲张性上消化道出血 内镜 钛夹封闭时间 止血 再出血
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电容式加速度传感器下电梯制动器制停时间预测算法
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作者 李长江 赵路宁 +1 位作者 李守贝 李明明 《传感器世界》 2024年第1期18-22,34,共6页
电梯制动器制停时间的预测需要大量的实时传感器数据,由于受到噪声和不准确度等因素的影响,存在数据稀疏性和不完整性的问题,导致预测精度与效率较低。为此,提出电容式加速度传感器下的电梯制动器制停时间预测研究。采用电容式加速度传... 电梯制动器制停时间的预测需要大量的实时传感器数据,由于受到噪声和不准确度等因素的影响,存在数据稀疏性和不完整性的问题,导致预测精度与效率较低。为此,提出电容式加速度传感器下的电梯制动器制停时间预测研究。采用电容式加速度传感器实时采集电梯制动器制停过程中的加速度数据;对采集的数据进行二阶正反馈带通滤波处理,消除可能存在的噪声或不必要的频率成分;利用傅立叶分析技术对加速度数据进行误差补偿处理,以减少由于传感器本身或其他因素引起的误差对制停时间预测的影响;基于已经滤波和误差补偿过的加速度数据,结合牛顿第二定律可以估算出电梯制动器的制停时间。经实验证明,设计方法预测平均百分比误差小于1%,预测耗时短于1ms,可以实现对电梯制动器制停时间高精度快速预测。 展开更多
关键词 电容式加速度传感器 电梯制动器 制停时间 二阶正反馈带通滤波 傅立叶分析 误差补偿
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基于飞行时间的自动扶梯速度及制停距离测量装置开发
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作者 孙学礼 刘英杰 +3 位作者 武星军 陈志刚 何山 陈敏 《机电工程技术》 2024年第5期50-53,共4页
针对自动扶梯运行速度及制停距离测量问题,提出了一种基于飞行时间的无接触测量方法,并开发了相应的装置。运行速度测量时,将激光测距模块置于自动扶梯中段的上方,测量梯级的垂直方向上高度变化和上升速度,通过计算得出垂直方向上升速度... 针对自动扶梯运行速度及制停距离测量问题,提出了一种基于飞行时间的无接触测量方法,并开发了相应的装置。运行速度测量时,将激光测距模块置于自动扶梯中段的上方,测量梯级的垂直方向上高度变化和上升速度,通过计算得出垂直方向上升速度,再根据扶梯倾斜角度计算得到扶梯运行速度;制停距离测量时,将电流感应模块至于动力回路的线路处,通过检测动力回路电流的通断触发激光测距模块进入制停距离测量模式,测量断电后梯级垂直上升的距离,再通过计算得出扶梯制停距离。开发基于μC/OS-III实时操作系统的手持设备,用于控制激光测距模块的开关及采集/显示自动扶梯速度和制停距离。激光测距模块、电流感应模块及手持模块采用Zigbee无线网络连接。试验结果表明,该装置可有效测得自动扶梯运行速度、制停距离,且安装方便,可重复性高,能提高检验效率及精度。 展开更多
关键词 自动扶梯运行速度 制停距离 飞行时间 μC/OS-III实时操作系统 ZIGBEE无线网络
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列车相对制动安全间隔模型的参数敏感度分析
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作者 钱华 吕浩炯 《控制与信息技术》 2024年第3期21-28,共8页
基于相对制动安全间隔模型的虚拟编组列车间安全间隔的量值大小对轨道线路的通行能力规划、基础设施建设以及车的设计等产生巨大的影响。为充分发挥虚拟联挂列车运行高效性并确保其行车安全,文章对影响安全间隔大小的关键参数进行敏感... 基于相对制动安全间隔模型的虚拟编组列车间安全间隔的量值大小对轨道线路的通行能力规划、基础设施建设以及车的设计等产生巨大的影响。为充分发挥虚拟联挂列车运行高效性并确保其行车安全,文章对影响安全间隔大小的关键参数进行敏感度分析,采用安全时距模型定性分析和模型加算法联合仿真定量分析的方法,得出相对制动安全间隔模型中的关键参数变化对停站时间差的影响程度。用单因素轮换法获得对应参数局部敏感度排序,由大到小分别为制动率、响应延迟时间、“制动建立”阶段时间和目标停站间距,从而指出关键参数选取的范围和原则以及安全间隔设计的优化方向。为使停站时间差可控且达到小于4 s的目标,进站过程采用3阶段紧急制动模型,并推荐了适宜的典型组合指标,即在后车制动率大于1.0 m/s^(2)、响应延迟时间小于1 s、最小安全间距2 m的基础上目标停站间距大于4 m,为现阶段列车虚拟联挂技术的工程化实施提供依据。 展开更多
关键词 虚拟编组列车 停站时间差 相对制动安全间隔模型 时距 参数敏感度
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