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941.
Ageing in general is associated with functional decline that may have an adverse effect on driving. Nevertheless, older drivers have been found to show good judgement and to self-regulate their driving, which may enable them to continue driving safely despite functional decline. The process of the self-monitoring of driving ability and the awareness of functional decline, and its association with the self-regulation of driving is, however, not fully understood. The aim of the present study was to examine the perceived changes in driving skills, the discomfort experienced in driving, and the self-regulation of driving as measured by the avoidance of certain driving situations by older drivers with different levels of self-rated cognitive problems. Eight hundred and forty Danish drivers aged 75–95 completed a structured telephone interview. The results showed that the recognition of cognitive problems was associated with an experience of improvement in higher level driving skills but also of a decline in lower level driving skills. Moreover, cognitive problems recognised by drivers were associated with discomfort in, and avoidance of, driving situations. Finally, a linear relationship between discomfort in driving and avoidance was found and this tended to be stronger for drivers recognising cognitive problems. The results indicate that older drivers who recognise problems with cognitive functions display good self-assessment of changes in their driving skills. In addition, the results suggest that driving-related discomfort is an important factor affecting the self-regulation of driving. Finally, the findings indicate that driving-related discomfort functions as an indirect self-monitoring of driving ability and may contribute to the safe driving performance of Danish older drivers. 相似文献
942.
针对汽车检测线控制系统中数据库和数据库表异构现象明显的现状,研究了一种基于DTS的数据源转换技术.首先介绍了SQL Server中用于数据转换的软件组件DTS,分析了异构数据源转换的关键技术;然后利用汽车检测线数据库设计时的各种信息,包括各个表、字段的含义以及数据类型、数据值的约束条件等,通过DTS图形化设计器设计了汽车检测线异构数据源的DTS转换包;最后通过前端VB.net程序调用DTS包对象的Execute方法运行DTS转换包,实现了汽车检测线Access数据源到SQL Server数据源的转换,达到了统一和规范汽车检测线数据源的目的. 相似文献
943.
研究了“灯芯效应”下珊瑚骨料混凝土在Mg2+、SO42-共同作用下Cl-的传输规律,建立了“灯芯效应”下珊瑚骨料混凝土Cl-传输模型.结果表明:Cl-沿半浸泡混凝土高度方向由下而上传输的同时也由表层向中心传输,其在混凝土内部的含量呈类抛物面分布;SO42-的存在会加快Cl-在混凝土中的传输,而Mg2+的加入会抑制Cl-的传输,导致混凝土在相同高度及深度处的Cl-含量小于SO42-与Cl-共同作用下的Cl-含量;本文建立的“灯芯效应”下珊瑚骨料混凝土氯离子传输模型计算结果与实测结果吻合良好. 相似文献
944.
Models commonly used in literature are evaluated versus 696 data points to predict the pressure drop of gas/non‐Newtonian power‐law fluids flow in horizontal pipes. Suitable models are recommended. A new correlation is developed by ignoring the pressure drop across the gas slug and adopting the liquid slug holdup of gas/non‐Newtonian fluid flow into the homogeneous model. The theoretical curves can capture the test data trends and the overall agreement of predicted values with experimental data is sufficient to be practically applied in industry. 相似文献
945.
通过对连铸实际生产过程中影响中间包使用寿命的原因分析,制定提高中间包使用寿命的措施,并在生产实践中取得了预期效果. 相似文献
946.
<正>1存在的问题我公司生料磨型号为ATOX50,该立磨自2008年3月投产以来,磨况较稳定。截止到2015年夏季,为了满足更严格的环保排放要求,窑尾电收尘更换为电袋复合型收尘器。技改收尘后,收尘效果提高,粉尘含量由25 mg/m~3下降到15 mg/m~3左右,收尘器进出口压差由1 500 Pa增加到2 500 Pa左右,运行阻力增加较多;磨机台时产量下降了25 t/h,磨机振动在0.5~0.7mm之间,压差偏高达6700~7200Pa,料层 相似文献
947.
Yixiu Wang Chao Li Fanchao Meng Shuling Lv Jintao Guo Xiaoqin Liu Chongqing Wang Zhengfei Ma 《Frontiers of Chemical Science and Engineering》2014,8(3):340-345
A CuAlCl4 doped metal organic framework, CuAlCl4@MIL-101, was prepared by introducing CuAlCl4 into the pores of MIL-101 for the selective adsorption of CO over N2. The CuAlCl4 molecules were evenly distributed into various pores sizes and did not change the intrinsic structure of the MIL-101. Isotherms for CO and N2 adsorption at 298 K showed that the CO capacity on CuAlCl4@MIL-101 was much higher than that on virgin MIL-101, whereas the N2 capacity decreased. The selectivity for CO over N2 improved from 4.64 to 31.5 at 298 K and 1 bar. The CuAlCl4@MIL-101 adsorbent displayed outstanding CO adsorption stability and the adsorbent could be regenerated by applying a simple vacuum of 4 mmHg. 相似文献
948.
结合园林水景多变的状态、多变的感官感受、多变的意境特征,对排比、通感、夸张、引用、比拟五种修辞手法在水景营造中的应用技巧进行了探讨,指出在水景的营造中适宜地运用修辞手法可使水景设计更加合理、动人,从而提高景观品质。 相似文献
949.
950.
Novel precipitant prepared through carbonation with MgCl2 wastewater generated from rare earth extraction separation process and low-price dolomite as raw materials was studied in this paper. The purification methods of novel precipitant by adding appropriate oxidizing agent were studied. It was found that optimal purification result could be achieved with sodium hypochlorite as iron removal reagent and the iron removal rate could reach up to 90% when the adding amount was 0.1 vol.%. During the preparation, the particle size and distribution of ceria-based polishing powder were affected obviously by the parameters such as concentration, reaction temperature and feeding rate. The results showed that ceria-based polishing powder with D50 =2.5-3.5 μm and the particle size distribution of 0.65-0.75 μm could be prepared when the concentration of CeCl3 was 0.6 mol/L, the reaction temperature was maintained at 50 °C and the feeding speed was controlled at 25 ml/min. Compared with commercial powder, the self-made polishing powder had roughly the same cutting amount, but the surface finish of polished glass was better than that of commercial polishing powder. 相似文献