“心肌荣”口服液对充血性心力衰竭患者的急性血液动力学效应

分组观察＂心肌荣＂口服液对３２例慢性充血性心力衰竭（ＣＨＦ）患者的急性血液动力学效应。结果表明：口服＂心肌荣＂４０、１００ｍｌ组，在服药后平均肺动脉压（ＭＰＡＰ）、肺楔压（ＰＷＰ）明显下降，而心脏指数（ＣＩ）明显上升（Ｐ＜０．０５），此作用维持４ｈ，提示口服＂心肌荣＂４０ｍｌ，每天３次，可治疗在性ＣＨＦ．     

既有建筑物桩基下暗挖车站施工的模拟分析

结合广州市轨道交通六号线东山口车站暗挖施工对既有建筑物的影响问题,阐明了该工程的施工方案,给出了建筑物安全性的评价标准。并利用ANSYS8.1有限元计算程序,对开挖方案进行数值模拟。论证了各施工步建筑物的安全性,为该工程顺利施工提供了理论依据和指导作用,取得了一些有意义的成果。     

254例糖尿病患者的死因分析

目的分析糖尿病(DM)死亡原因,为防治提供依据。方法回顾性分析西安交通大学医学院第一、二附属医院自1991年1月1日至2003年12月31日期间住院的DM死亡病例。结果13年两院DM死亡254例,占住院总死亡人数3.2%;死因依次为:慢性并发症42.5%(心脑血管病28.3%,肾病14.2%),肿瘤20.1%,感染11.4%,急性并发症6.7%,肝硬化6.3%;慢性并发症死因中合并高血压66.7%(72/108)。结论慢性并发症已成为DM的主要死因,其中心脑血管病变是最重要的,高血压是增加其死亡率的主要危险因素。因此,严格控制血糖和血压,对降低DM心脑血管病变的病死率有重要意义。     

尼古丁损伤大鼠肠系膜动脉内皮功能及卡托普利的干预作用

目的观察尼古丁对大鼠离体肠系膜动脉内皮依赖性舒张反应的影响以及卡托普利的干预作用。方法应用器官培养技术和离体血管环张力描记法,研究不同浓度的尼古丁(10-5、10-4、10-3mol/L)在有或无卡托普利(0.01、0.030、.1 mmol/L)的情况下,对培养24 h的成年SD大鼠肠系膜动脉环(1 mm)内皮依赖性舒张反应的影响。结果尼古丁呈浓度依赖性损伤乙酰胆碱(ACh)诱导的内皮依赖性血管舒张反应(P<0.01,与空白对照组比较)。卡托普利呈浓度依赖性改善尼古丁对血管内皮依赖性舒张反应的损害。低浓度时对尼古丁损伤没有明显影响,高浓度具有显著的保护作用(P<0.05,与尼古丁10-4mol/L组比较)。结论卡托普利对尼古丁所引起的血管内皮依赖性舒张功能的损伤具有明显的保护作用。     

一种分析APF直流侧电压谐波含量的新方法

有源电力滤波器在船舶电网中得到了广泛的应用。然而有源电力滤波器在补偿电流时实际发出的电流存在静差、直流侧电压存在波动。为了提高有源电力滤波器的补偿精度,找出补偿时存在误差的根本原因,本文围绕APF的数学模型、补偿机理、瞬时功率理论来具体讨论在船舶电网不平衡下的APF直流侧电压波动成分,并对以往的储能电容的计算公式进行修正。     

硝酸银生产工艺改进研究及效果

改进了硝酸银生产工艺中的除杂、过滤和蒸发环节,通过试验确定了新的工艺参数,改进后大大提高了生产效率和产能,减小了劳动量、银损耗,质量更加稳定。     

Short‐term traffic flow prediction with linear conditional Gaussian Bayesian network

Traffic flow prediction is an essential part of intelligent transportation systems (ITS). Most of the previous traffic flow prediction work treated traffic flow as a time series process only, ignoring the spatial relationship from the upstream flows or the correlation with other traffic attributes like speed and density. In this paper, we utilize a linear conditional Gaussian (LCG) Bayesian network (BN) model to consider both spatial and temporal dimensions of traffic as well as speed information for short‐term traffic flow prediction. The LCG BN allows both continuous and discrete variables, which enables the consideration of categorical variables in traffic flow prediction. A microscopic traffic simulation dataset is used to test the performance of the proposed model compared to other popular approaches under different predicting time intervals. In addition, the authors investigate the importance of spatial data and speed data in flow prediction by comparing models with different levels of information. The results indicate that the prediction accuracy will increase significantly when both spatial data and speed data are included. Copyright © 2016 John Wiley & Sons, Ltd.     

A G/G(n)/C/C state‐dependent simulation model for metro station corridor width design

Metro station corridor and passengers are described as a G/G(n)/C/C state‐dependent queuing system with a general random arrival interval G and a general random and state‐dependent service time G(n) to offset the shortcomings in existing design methods. The corresponding G/G(n)/C/C state‐dependent discrete event simulation model is developed, and its high‐fidelity is tested. Then the optimization algorithm based on the simulation model is designed to determine corridor width. The proposed simulation optimization method and the existing analytical optimization methods, based on M/G(n)/C/C and D/D/1/C queuing models, are applied to design corridor width in a numerical example of 48 combinations of passenger flow rates and level of service (LOS). The designed corridor widths are tested in a micro‐simulation model, and the performance measure is compared. The result shows that the corridor widths obtained by the new method are 0.357 m (7.4%) larger than that of the other two methods on average; the area per passenger of the new method increases 10.53% and 11.63%, respectively, compared with that of the other two methods; the widths designed by the new method satisfy the requirement of LOS under various passenger flows, whereas 93% of the corridor widths obtained by the other two methods fail to meet the requirement of LOS, and the corridor widths designed by the new method have high elasticity coefficients of LOS‐width. Copyright © 2015 John Wiley & Sons, Ltd.     

绞吸挖泥船横移过程二次型最优控制

在疏浚作业过程中,挖泥船主要的作业参数是由操作人员根据自己的经验、试挖情况以及挖泥船实际作业效果灵活确定的,而疏浚操作人员的经验和理论水平也相差较大,所以手动作业的实际产量要远远低于预计产量,效率低下,作业成本偏高,作业质量较差。为了克服该缺点,本文提出了一种基于疏浚系统状态空间模型的线性二次型最优控制策略,并设计了最优控制跟踪器应用于绞吸挖泥船横移过程的控制中,该跟踪器是智能控制替代人工操作的一种有效方法。文中对应用二次型最优控制策略的效果进行了MATLAB仿真分析,仿真结果表明：采用了二次型最优控制策略后,系统稳定、响应快、滞后小,对期望输出的跟踪性好,可以应用于挖泥船疏浚作业过程中。     

主动前轮转向控制技术的现状与发展趋势

文章在介绍两种主动前轮转向系统工作原理的基础上,从车辆动力学控制的角度,详细总结和分析了各种用于主动前轮转向的控制方法,包括横摆角速度控制、D*控制、侧倾稳定性控制和变转向传动比控制等。并指出在未来的主动前轮转向控制研究中,集成控制将是发展的必然方向。