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Strongly Non-Regularity of Order Bounded Operators
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作者 陈滋利 《Journal of Modern Transportation》 1998年第2期72-77,共6页
A method to construct strongly non regular order bounded operators from a classical Banach lattice C into any separable Banach lattice F without Dedekind σ completeness is presented in this paper. A r... A method to construct strongly non regular order bounded operators from a classical Banach lattice C into any separable Banach lattice F without Dedekind σ completeness is presented in this paper. A result concerning the order bounded norm and the regular norm is also contained. 展开更多
关键词 Banach lattice order bounded strongly non regular
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Graph Regularized L_p Smooth Non-negative Matrix Factorization for Data Representation 被引量:10
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作者 Chengcai Leng Hai Zhang +2 位作者 Guorong Cai Irene Cheng Anup Basu 《IEEE/CAA Journal of Automatica Sinica》 EI CSCD 2019年第2期584-595,共12页
This paper proposes a Graph regularized Lpsmooth non-negative matrix factorization(GSNMF) method by incorporating graph regularization and L_p smoothing constraint, which considers the intrinsic geometric information ... This paper proposes a Graph regularized Lpsmooth non-negative matrix factorization(GSNMF) method by incorporating graph regularization and L_p smoothing constraint, which considers the intrinsic geometric information of a data set and produces smooth and stable solutions. The main contributions are as follows: first, graph regularization is added into NMF to discover the hidden semantics and simultaneously respect the intrinsic geometric structure information of a data set. Second,the Lpsmoothing constraint is incorporated into NMF to combine the merits of isotropic(L_2-norm) and anisotropic(L_1-norm)diffusion smoothing, and produces a smooth and more accurate solution to the optimization problem. Finally, the update rules and proof of convergence of GSNMF are given. Experiments on several data sets show that the proposed method outperforms related state-of-the-art methods. 展开更多
关键词 Data clustering dimensionality reduction GRAPH regularIZATION LP SMOOTH non-negative matrix factorization(SNMF)
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Exercise training in the management of patients with resistant hypertension 被引量:6
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作者 Fernando Ribeiro Rui Costa José Mesquita-Bastos 《World Journal of Cardiology》 CAS 2015年第2期47-51,共5页
Hypertension is a very prevalent risk factor for cardiovascular disease. The prevalence of resistant hypertension, i.e., uncontrolled hypertension with 3 or more antihypertensive agents including 1 diuretic, is betwee... Hypertension is a very prevalent risk factor for cardiovascular disease. The prevalence of resistant hypertension, i.e., uncontrolled hypertension with 3 or more antihypertensive agents including 1 diuretic, is between 5% and 30% in the hypertensive population. The causes of resistant hypertension are multifactorial and include behavioral and biological factors, such as nonadherence to pharmacological treatment. All current treatment guidelines highlight the positive role of physical exercise as a non-pharmacological tool in the treatment of hypertension. This paper draws attention to the possible role of physical exercise as an adjunct non-pharmacological tool in the management of resistant hypertension. A few studies have investigated it, employing different methodologies, and taken together they have shown promising results. In summary, the available evidence suggests that aerobic physical exercise could be a valuable addition to the optimal pharmacological treatment of patients with resistant hypertension. 展开更多
关键词 EXERCISE training RESISTANT HYPERTENSION BLOOD pressure non-PHARMACOLOGICAL CARDIOVASCULAR disease
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Design and Experiment of Non-circular Combined Gear Train Beating-up Mechanism 被引量:1
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作者 CHEN Jianneng YU Chennan +3 位作者 TONG Lin WANG Ying XIA Xudong ZHAO Xiong 《Journal of Donghua University(English Edition)》 EI CAS 2019年第1期8-14,共7页
The most important performance of a beating-up mechanism is that the dwelling time of the sley must ensure the completion of the weft insertion. To meet this requirement, a new non-circular combined gear train beating... The most important performance of a beating-up mechanism is that the dwelling time of the sley must ensure the completion of the weft insertion. To meet this requirement, a new non-circular combined gear train beating-up mechanism which is composed of two-stage planetary gear trains is proposed. The first-stage is a Fourier planetary gear train and the second-stage is a non-circular planetary gear train. For designing of this new mechanism, the ideal kinematic equations of the sley are constructed first. Then the kinematic model of the first-stage Fourier planetary gear train is established and the reverse solution for the pitch curves of the second-stage non-circular gears is deduced. With a computer-aided design program, the influences of several important parameters on the pitch curves of the second-stage non-circular gears are analyzed, and a set of preferable structural parameters are obtained. Finally, a test bed of this mechanism is developed and the experimental results show that this new beating-up mechanism can achieve the designed dwelling time, namely it can meet the requirements of beating-up process. 展开更多
关键词 beating-up mechanism FOURIER GEAR non-CIRCULAR GEAR PLANETARY GEAR train KINEMATIC
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Performance index based learning controls for the partial non-regular systems using lifting technique
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作者 Shengyue YANG Xiaoping FAN Zhihua QU 《控制理论与应用(英文版)》 EI 2009年第2期197-201,共5页
Deficiencies of the performance-based iterative learning control (ILC) for the non-regular systems are investigated in detail, then a faster control input updating and lifting technique is introduced in the design o... Deficiencies of the performance-based iterative learning control (ILC) for the non-regular systems are investigated in detail, then a faster control input updating and lifting technique is introduced in the design of performance index based ILCs for the partial non-regular systems. Two ldnds of optimal ILCs based on different performance indices are considered. Finally, simulation examples are given to illustrate the feasibility of the proposed learning controls. 展开更多
关键词 Iterative learning control non-regular systems Lifting technique
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Study on the pattern of train arrival headway time in high-speed railway
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作者 Changhai Tian Shoushuai Zhang 《Railway Sciences》 2024年第3期344-366,共23页
Purpose-The design goal for the tracking interval of high-speed railway trains in China is 3 min,but it is difficult to achieve,and it is widely believed that it is mainly limited by the tracking interval of train arr... Purpose-The design goal for the tracking interval of high-speed railway trains in China is 3 min,but it is difficult to achieve,and it is widely believed that it is mainly limited by the tracking interval of train arrivals.If the train arrival tracking interval can be compressed,it will be beneficial for China's high-speed railway to achieve a 3-min train tracking interval.The goal of this article is to study how to compress the train arrival tracking interval.Design/methodologylapproach-By simulating the process of dense train groups arriving at the station and stopping,the headway between train arrivals at the station was calculated,and the pattern of train arrival headway was obtained,changing the traditional understanding that the train arrival headway is considered the main factor limiting the headway of trains.Findings-When the running speed of trains is high,the headway between trains is short,the length of the station approach throat area is considerable and frequent train arrivals at the station,the arrival headway for the first group or several groups of trains will exceed the headway,but the subsequent sets of trains will havea headway equal to the arrival headway.This convergence characteristic is obtained by appropriately increasing the running time.Originality/value-According to this pattern,there is no need to overly emphasize the impact of train arrival headway on the headway.This plays an important role in compressing train headway and improving high-speedrailwaycapacity. 展开更多
关键词 High speed railway train headway train arrival headway regular pattern Paper type Research paper
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Entropy Production in a Non-Isolated Thermodynamic System Taking into Account Regular Factors of Nonrandom Nature
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作者 A. Yu. Khlestkov Yu. A. Khlestkov +2 位作者 N. Yu. Lukashina M. Yu. Lukashin P. Yu. Lukashin 《Journal of Modern Physics》 2020年第3期343-354,共12页
The work illustrates the impossibility of decreasing entropy in a strictly random thermodynamic process in a non-isolated system using the example of heating a planet by solar radiation flux without and taking into ac... The work illustrates the impossibility of decreasing entropy in a strictly random thermodynamic process in a non-isolated system using the example of heating a planet by solar radiation flux without and taking into account its rotation around its own axis. That is, the second law of thermodynamics formulated for isolated systems continues to govern such systems. We have shown that in order to achieve a stationary state at lower values of temperature and entropy far from thermodynamic equilibrium at a maximum of temperature and entropy, it is necessary to have regular factors of nonrandom nature, one of which in this example is the rotation of the planet around its own axis. This means that the reason for the appearance of ordered structured objects in non-isolated thermodynamic systems is not the random process itself, but the action of dynamic control mechanisms, such as periodic external influences, nonlinear elements with positive feedback, catalysts for chemical reactions, etc. We present the plots with dependences of temperature and entropy versus time in non-isolated systems with purely random processes and in the presence of a control factor of non-random nature-rotation. 展开更多
关键词 RANDOM Process non-Isolated Systems Entropy Ordered Structures regular Factors of non-Random NATURE
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Non-Regular Example of Confidence-Interval Construction
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作者 Jan Vrbik 《Open Journal of Statistics》 2023年第4期475-491,共17页
When dealing with a regular (fixed-support) one-parameter distribution, the corresponding maximum-likelihood estimator (MLE) is, to a good approximation, normally distributed. But, when the support boundaries are func... When dealing with a regular (fixed-support) one-parameter distribution, the corresponding maximum-likelihood estimator (MLE) is, to a good approximation, normally distributed. But, when the support boundaries are functions of the parameter, finding good approximation for the sampling distribution of MLE (needed to construct an accurate confidence interval for the parameter’s true value) may get very challenging. We demonstrate the nature of this problem, and show how to deal with it, by a detailed study of a specific situation. We also indicate several possible ways to bypass MLE by proposing alternate estimators;these, having relatively simple sampling distributions, then make constructing a confidence interval rather routine. . 展开更多
关键词 non-regular Parameter Estimation Maximum-Likelihood Estimator Asymptotic Distribution Largest-Order Statistic Monte-Carlo Simulation
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Non-Regular Example of Confidence-Interval Construction
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作者 Jan Vrbik 《Open Journal of Endocrine and Metabolic Diseases》 2023年第4期475-491,共17页
When dealing with a regular (fixed-support) one-parameter distribution, the corresponding maximum-likelihood estimator (MLE) is, to a good approximation, normally distributed. But, when the support boundaries are func... When dealing with a regular (fixed-support) one-parameter distribution, the corresponding maximum-likelihood estimator (MLE) is, to a good approximation, normally distributed. But, when the support boundaries are functions of the parameter, finding good approximation for the sampling distribution of MLE (needed to construct an accurate confidence interval for the parameter’s true value) may get very challenging. We demonstrate the nature of this problem, and show how to deal with it, by a detailed study of a specific situation. We also indicate several possible ways to bypass MLE by proposing alternate estimators;these, having relatively simple sampling distributions, then make constructing a confidence interval rather routine. . 展开更多
关键词 non-regular Parameter Estimation Maximum-Likelihood Estimator Asymptotic Distribution Largest-Order Statistic Monte-Carlo Simulation
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生物反馈助力电刺激对慢性非特异性腰痛患者下肢步行功能的改善
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作者 郑翔 张明兴 +1 位作者 黄雅 单莎瑞 《中国组织工程研究》 CAS 北大核心 2025年第3期547-553,共7页
背景:国内外关于慢性非特异性腰痛生物反馈疗法和三维步态功能分析的相关研究已开展很多,但是对二者结合的研究少有报道。目的:利用三维步态分析采集步态参数数据,研究生物反馈助力电刺激对慢性非特异性腰痛患者步行能力的改变效果。方... 背景:国内外关于慢性非特异性腰痛生物反馈疗法和三维步态功能分析的相关研究已开展很多,但是对二者结合的研究少有报道。目的:利用三维步态分析采集步态参数数据,研究生物反馈助力电刺激对慢性非特异性腰痛患者步行能力的改变效果。方法:选择2021年6月至2022年9月在广东药科大学附属第一医院收治的60例慢性非特异性腰痛患者,男34例,女26例,年龄32-58岁。采用随机数字表法将60例患者分为对照组(n=30)与试验组(n=30),两组患者均接受腰部动态干扰电的常规治疗(20 min/次,1次/d,每周5次,持续治疗20次),对照组患者在常规治疗的基础上进行仰卧搭桥和俯卧搭桥的悬吊核心肌群训练(每周5次,持续治疗20次),试验组在对照组治疗的基础上进行生物反馈助力电刺激治疗(20 min/次,1次/d,每周5次,持续治疗20次)。比较分析两组患者治疗前后的腰痛评分、肌电信号平均值和步态参数。结果与结论:①两组患者治疗结束后的数字类比表评分、日本骨科协会(JOA)评分、Oswestry功能障碍指数均较治疗前明显改善(P<0.05),试验组治疗结束后的数字类比表评分、JOA评分、Oswestry功能障碍指数均优于对照组(P<0.05);②两组患者治疗结束后的腹直肌、臀大肌、竖脊肌表面肌电平均值均高于治疗前(P<0.05),试验组治疗结束后的腹直肌、臀大肌、竖脊肌表面肌电平均值均高于对照组(P<0.05);③两组患者治疗结束后的步宽、步速、步频、健患侧步长比值、健患侧支撑相比值、患健侧摆动相比值、健患侧髋关节及膝关节矢状面活动度和健患侧足偏角均优于治疗前(P<0.05),试验组治疗结束后的上述指标均优于对照组(P<0.05);④结果表明,生物反馈助力电刺激能明显缓解慢性非特异性腰痛,改善了患者下肢步行功能。 展开更多
关键词 三维步态 生物反馈助力电刺激 慢性非特异性腰痛 步行功能 核心稳定训练
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A Probe into the Reasons for Less Frequent Use of Memory Strategies by Chinese Non-English Majors
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作者 赵欣 《内蒙古工业大学学报(社会科学版)》 2006年第2期122-124,128,共4页
Based on the results of the questionnaire survey,supplemented with the classroom observation and individual interview,the author probes into the reasons why Chinese non-English majors use memory strategies infrequentl... Based on the results of the questionnaire survey,supplemented with the classroom observation and individual interview,the author probes into the reasons why Chinese non-English majors use memory strategies infrequently.On the one hand,the students do not know about memory techniques and on the other hand,they seldom receive memory strategy training in class.Therefore,it is strongly suggested that teachers be encouraged to become familiar with recent learner strategy research findings,and integrate the teaching of language learning strategies with classroom instruction plans.Only in this way can they offer their students a great deal of guidance in experimenting with new different strategies to enhance their learning. 展开更多
关键词 非专业英语 记忆策略 教学方法 策略训练
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Experiments on Transformation and Run-Up of Wave Trains
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作者 董国海 李玉成 《China Ocean Engineering》 SCIE EI 2000年第3期329-337,共9页
This paper. details experiments undertaken in the UK Coastal Research Facility (CRF)at Hy draulies Research (HR), Wallingford, on transformation and run-up of wave trains. The purpose of these experiments is to provid... This paper. details experiments undertaken in the UK Coastal Research Facility (CRF)at Hy draulies Research (HR), Wallingford, on transformation and run-up of wave trains. The purpose of these experiments is to provide verification data for numerical models of wave transformation in shoaling. surf and swash zones. This is the kind of data ih:lt flume experiments are unable to provide, and is collected in the highly controlled environment of CRF where extrinsic factors present in the field are not an issue. The experiments concerning wave trains are undertaken by use of existing wave generation software, and the run-up measurements are made with large experimental run-up gauges. 展开更多
关键词 EXPERIMENT TRANSFORMATION wave train RUN-UP random waves regular waves
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Automatic Scallion Seedling Feeding Mechanism with an Asymmetrical High-order Transmission Gear Train 被引量:4
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作者 Xiong Zhao Jun Ye +2 位作者 Mengyan Chu Li Dai Jianneng Chen 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2020年第1期148-161,共14页
The current automatic scallion-transplanting machine is a complicated mechanism composed of two linkage mechanisms and two band carriers.It delivers seedlings ine ciently because of the movement limitations of the lin... The current automatic scallion-transplanting machine is a complicated mechanism composed of two linkage mechanisms and two band carriers.It delivers seedlings ine ciently because of the movement limitations of the linkage mechanism.This paper proposes a new high-order non-circular gear train for an automatic scallion-seedling feeding mechanism.The proposed gear train has an asymmetrical transmission ratio;i.e.,its transmission ratio varies.This allows the mechanism’s execution component to move in a long displacement and rotate in a large rotation angle.The long displacement enables the execution component to reach the designed working position,and the large rotation angle allows it to feed a scallion in the required pose.A mathematical model for calculating the asymmetrical transmission ratio was established according to the closure requirements and the full-cycle motion of the driven gear pitch curve.Then,the parameter-design model of the new seedling-feeding mechanism was established,based on precise pose points and trajectory-shape control points.Moreover,an aided-design program was developed to obtain the parameter-solution domain of the scallion-seedling feeding mechanism.The mechanism parameters,which met the seedling-feeding function,were optimized to determine the transmission ratio,using a program and a kinematic simulation.Finally,a prototype of the mechanism was produced,and a seedling-feeding experiment was carried out.One-thousand seedlings were tested at a rate of 100 seedlings per minute,and the statistical success rate was 93.4%.Thus,the automatic scallion-seedling feeding mechanism significantly improves the e ciency of automatically transplanting scallions. 展开更多
关键词 Asymmetric TRANSMISSION Scallion TRANSPLANTING HIGH-ORDER GEAR non-CIRCULAR GEAR Planetary GEAR train
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A Non-homentropic Numerical Method for Calculating Pressure Transient in Tunnels with Airshafts
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作者 金纪峰 赵海恒 《Journal of Modern Transportation》 1999年第1期118-125,共8页
A one dimensional unsteady compressible non homentropic flow prediction method for calculating the pressure transient generated by a high speed train passing through a tunnel with airshafts is presented. Boundary co... A one dimensional unsteady compressible non homentropic flow prediction method for calculating the pressure transient generated by a high speed train passing through a tunnel with airshafts is presented. Boundary conditions for airshafts are proposed. The calculated results coincide with experiments well. The computational results of a high speed train passing through a tunnel with two airshafts indicate that airshafts can be used to reduce the magnitude of the pressure generated by the train in tunnel effectively. 展开更多
关键词 PRESSURE transient value TUNNELS airshaft high speed trains one dimensional non homentropic flow
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New Regularization Algorithms for Solving the Deconvolution Problem in Well Test Data Interpretation 被引量:1
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作者 Vladimir Vasin Georgy Skorik +1 位作者 Evgeny Pimonov Fikri Kuchuk 《Applied Mathematics》 2010年第5期387-399,共13页
Two new regularization algorithms for solving the first-kind Volterra integral equation, which describes the pressure-rate deconvolution problem in well test data interpretation, are developed in this paper. The main ... Two new regularization algorithms for solving the first-kind Volterra integral equation, which describes the pressure-rate deconvolution problem in well test data interpretation, are developed in this paper. The main features of the problem are the strong nonuniform scale of the solution and large errors (up to 15%) in the input data. In both algorithms, the solution is represented as decomposition on special basic functions, which satisfy given a priori information on solution, and this idea allow us significantly to improve the quality of approximate solution and simplify solving the minimization problem. The theoretical details of the algorithms, as well as the results of numerical experiments for proving robustness of the algorithms, are presented. 展开更多
关键词 DECONVOLUTION PROBLEM VOLTERRA Equations Well Test regularIZATION Algorithm Quasi-Solutions Method Tikhonov regularIZATION A Priori Information Discrete Approximation non-Quadratic Stabilizing Functional Special Basis
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情景模拟联合PBL教学法在脊柱侧弯住培教学中的应用研究 被引量:1
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作者 管俊杰 陈向东 +3 位作者 陈晓庆 姜星杰 姚羽 张烽 《中国继续医学教育》 2024年第1期54-57,共4页
目的 探究情景模拟联合以问题为导向的教学法(problem-based learning,PBL)在脊柱侧弯住培教学中的应用效果。方法 将2020年1月—2021年12月在南通大学附属医院骨科参加住培的40名学员作为研究对象,并随机分为对照组(n=20,给予PBL教学... 目的 探究情景模拟联合以问题为导向的教学法(problem-based learning,PBL)在脊柱侧弯住培教学中的应用效果。方法 将2020年1月—2021年12月在南通大学附属医院骨科参加住培的40名学员作为研究对象,并随机分为对照组(n=20,给予PBL教学法),观察组(n=20,给予情景模拟联合PBL教学法)。比较分析2组学员考核成绩、满意度及综合能力评价情况。结果在考核成绩方面,住培前2组学员考核成绩差异无统计学意义(P> 0.05),住培后观察组学员理论与实践的成绩分别是(91.04±3.14)分、(92.33±3.57)分,均高于对照组学员的(81.75±2.97)分、(82.64±2.69)分,且观察组综合得分(91.47±3.26)分高于对照组学员的(82.01±2.54)分,差异均有统计学意义(P<0.05)。观察组与对照组对住培教学的满意度(95.00%vs. 70.00%)的差异有统计学意义(P <0.05)。在综合能力评价方面,观察组学员综合评价总分(89.46±1.17)分,高于对照组学员的(70.27±1.22)分,差异有统计学意义(P <0.05)。结论 在脊柱侧弯住培教学中实施情景模拟联合PBL教学法可以有效提高学员的理论知识水平以及实践操作能力,并且学员的综合能力显著提高。 展开更多
关键词 骨科 脊柱侧弯 情景模拟 PBL 住培教学 效果
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翻转课堂联合SimMan 模拟人在住院医师ACLS非技术能力培训中的应用 被引量:2
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作者 王文静 齐向飞 +3 位作者 谭文君 李索妮 尚进 郭波 《医学教育研究与实践》 2024年第1期108-113,共6页
目的 本研究探讨翻转课堂教学法联合SimMan模拟人在住院医师高级心脏生命支持(advanced cardiac life support, ACLS)非技术能力培训中的应用效果。方法 选取西安交通大学第一附属医院80名三年级住院医师作为研究对象,将其随机分为翻转... 目的 本研究探讨翻转课堂教学法联合SimMan模拟人在住院医师高级心脏生命支持(advanced cardiac life support, ACLS)非技术能力培训中的应用效果。方法 选取西安交通大学第一附属医院80名三年级住院医师作为研究对象,将其随机分为翻转课堂组和传统课堂组,并应用SimMan模拟人进行ACLS的模拟培训。最后采用实践测试、非技术能力测试和问卷调查评估两种教学方法的培训效果。结果 翻转课堂组学员正确使用除颤仪得分、正确使用肾上腺素得分、团队合作得分及测试总得分高于传统课堂组学员,组间差异具有统计学意义(P<0.05)。较传统课堂组,翻转课堂组经过ACLS模拟培训后在情景意识、任务管理、团队合作及判断决策等非技术能力方面的合格率均明显升高(P<0.05)。问卷调查结果显示,翻转课堂组学员在良好的课堂互动、激发学习兴趣和积极性、加强团队合作和总体满意度方面优于传统课堂组,其差异均具有统计学意义(P<0.05)。结论 翻转课堂教学法联合SimMan模拟人可提高高年资住院医师的ACLS实践测试成绩和非技术能力,并增加学生满意度,在ACLS培训中具有重要的应用价值。 展开更多
关键词 翻转课堂 SimMan模拟人 住院医师 ACLS 非技术能力 培训
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Some Properties of a Recursive Procedure for High Dimensional Parameter Estimation in Linear Model with Regularization
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作者 Hong Son Hoang Remy Baraille 《Open Journal of Statistics》 2014年第11期921-932,共12页
Theoretical results related to properties of a regularized recursive algorithm for estimation of a high dimensional vector of parameters are presented and proved. The recursive character of the procedure is proposed t... Theoretical results related to properties of a regularized recursive algorithm for estimation of a high dimensional vector of parameters are presented and proved. The recursive character of the procedure is proposed to overcome the difficulties with high dimension of the observation vector in computation of a statistical regularized estimator. As to deal with high dimension of the vector of unknown parameters, the regularization is introduced by specifying a priori non-negative covariance structure for the vector of estimated parameters. Numerical example with Monte-Carlo simulation for a low-dimensional system as well as the state/parameter estimation in a very high dimensional oceanic model is presented to demonstrate the efficiency of the proposed approach. 展开更多
关键词 Linear Model regularIZATION RECURSIVE Algorithm non-Negative COVARIANCE Structure EIGENVALUE Decomposition
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Research on stepless transmission utilizing noncircular gears
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作者 张瑞 张爱梅 吴序堂 《Journal of Pharmaceutical Analysis》 SCIE CAS 2007年第2期164-171,共8页
In view of the lack of systemic analysis for stepless transmission using noncircular gears, two basic noncircular gear units, an addition unit adopting differential mechanism and a multiplication unit applying a fixed... In view of the lack of systemic analysis for stepless transmission using noncircular gears, two basic noncircular gear units, an addition unit adopting differential mechanism and a multiplication unit applying a fixed gear train, are proposed. Then, the design methods of the noncircular gear pair of each unit, transmission ratio relationship, rotation angle relationship and key parameters with specific physical meanings are studied. The adjusting properties, composing strategy and varying range of transmission ratio etc. are investigated in detail for each unit. Following this, several examples of using a noncircular gear pair in the units and their manipulation technique are introduced. 展开更多
关键词 non-circular gear stepless transmission fixed gear train differential mechanism
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基于非凸与不可分离正则化算法的电容层析成像图像重建 被引量:1
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作者 李宁 朱朋飞 +1 位作者 张立峰 卢栋臣 《化工学报》 EI CSCD 北大核心 2024年第3期836-846,共11页
搅拌器内两相混合是化工生产中常见的现象,电容层析成像(ECT)技术主要对两相分布进行可视化重构,以达到监测的目的。受稀疏贝叶斯学习的启发,提出了一种非凸与不可分离正则化(NNR)算法重建ECT图像。在稀疏先验的基础上引入矩阵低秩特性... 搅拌器内两相混合是化工生产中常见的现象,电容层析成像(ECT)技术主要对两相分布进行可视化重构,以达到监测的目的。受稀疏贝叶斯学习的启发,提出了一种非凸与不可分离正则化(NNR)算法重建ECT图像。在稀疏先验的基础上引入矩阵低秩特性,采用最大后验估计在潜在空间中提出一个新的优化问题,利用对偶变量将潜在空间的目标函数映射到原始空间进行迭代求解,用来恢复同时稀疏与低秩的矩阵。与凸近似L1范数相比,NNR算法可获得更准确的重建图像,同时比非凸可分离方法更容易收敛到全局最优解。为验证NNR算法的重建效果,通过数值仿真与静态实验的方法分别与其他5种算法进行重建对比。结果表明:NNR算法可以有效减少重建伪影,提升中心物体的重建质量,为搅拌器内两相分布提供了高质量的重建算法。 展开更多
关键词 电容层析成像 图像重建 非凸不可分离正则化 稀疏-低秩模型 两相混合
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