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Search Results: 1 - 10 of 92750 matches for " 周育名 "
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气温升高对多年冻土地区路基稳定性影响
李金明,,原喜忠
重庆交通大学学报(自然科学版) , 2011, DOI: 10.3969/j.issn.1674-0696.2011.02.19
Abstract: :?为了分析在气温升高的状况下冻土退化对东北多年冻土地区路基稳定性的影响,假设气温年增长率为0.05??,通过ANSYS有限元软件计算了不同地表状况和不同含冰量情况下,多年冻土最大季节融化深度变化,根据不同土质、不同含冰量的融沉系数,计算得到不同含冰量冻土的沉降量。结果表明:在气温逐年升高的状况下,含冰量大的土层沉降量大于含冰量小的土层;天然草皮泥炭对多年冻土的退化有一定的保护作用;人为活动的影响会使沉降量增加,从而对公路及铁路工程路基稳定性产生严重影响。
山区农村公路路侧安全保障技术
许金良,,杨宏志
长安大学学报(自然科学版) , 2011,
Abstract: 为了研究山区农村公路路侧安全影响因素、安全评价方法及安全保障措施,对陕西咸阳地区农村公路进行了实地调查,并结合专家意见,应用层次分析法和灰色理论进行了相关分析。结果表明影响山区农村公路路侧安全的因素有交通量、交通组成、路侧特征及线形特征;适用于山区农村公路路侧安全评价的10个指标为平曲线变量、竖曲线变量、白天平均小时交通量、摩托车比重、路侧事故数、路侧伤亡事故数、路侧净区满足率、路侧深度、离散危险物密度及横向距离;山区农村公路路侧危险度宜划分为3个等级Ⅰ级、Ⅱ级、Ⅲ级,且不同危险度等级应采用不同的安全防护对策。
路线走廊震害与环境基础因子关系研究
,许金良,杨宏志
武汉理工大学学报 , 2013,
Abstract: ?研究地震造成的路线走廊带灾害与环境因子的关系,减少滑坡、泥石流、崩塌等灾害的发生,降低地质灾害对道路的破坏。通过对5?12汶川地震重灾区内g213、g317道路路段的资料收集、实地调查,结合理论分析,以arcgis软件为基础平台,分析了断裂带距离、地质岩层、地表粗糙度、坡度、坡向、植被类型、道路影响区共7个因子与地质灾害产生的关系。结果表明:距断裂带越远,受到影响越小;地质岩层越古老,越易发生灾害,岩质坡体灾害少于土质坡体;地表粗糙程度为1.2~2时,灾害的密度比较大;坡度为30°~60°时,灾害密度最大;阴坡灾害多于阳坡;阔叶林地带灾害密度分布最大;道路左右0.5km区域灾害密度最大。
用碘电极测定磷矿中碘
李如柏,,,陈满梅
分析化学 , 1978,
Abstract: 磷矿中碘的测定多采用碘兰比色法,或催化比色和催化滴定法。我们采用碘电极直接电位法测定磷矿中碘,不经任何分离可直接测定含碘百万分之一以上的矿样。作为碘的一种较为灵敏、简便、快速的分析方法,可试用于当前磷矿中碘的地质普查及回收生产。
西北地区公路交通价值评估指标体系
许金良,,王玉平,贾兴利
长安大学学报(自然科学版) , 2014,
Abstract: 针对目前中国公路交通价值评估体系研究不完善的现状,以西北地区为研究对象,分析公路交通综合价值,以凸显其除经济以外的其他具有区域特点的贡献。定义了公路交通价值,对西北地区公路交通价值进行了分类,构建了包含功利性价值和超功利性价值的西北地区公路交通价值评估指标体系;提出采用多层次模糊综合评判模型作为西北地区公路交通价值的评估方法,并以陕西省公路交通基础设施情况为例,对所建立的评估指标体系及方法进行验证。分析结果表明西北地区公路交通价值宜分为功利性与超功利价值两大类,前者包括经济价值、社会价值、政治价值及军事价值,后者包括公平价值和扶贫价值;陕西省公路交通价值结果为社会价值极大,经济、军事及扶贫价值较大,政治、公平价值一般,综合评估效果较大;本指标体系对合理确定西北地区公路投资建设、路网规模、公路等级和技术标准具有指导性意义。
驾驶人次任务转换特性研究
Research on characteristics of driver task conversion

王磊,杨明煊,孙宇,朱彤,
- , 2018,
Abstract: 为探究驾驶人次任务完成后对速度判断的影响,以及次任务难度和任务间隔时间2个因素对任务转换代价的具体影响,利用E??Prime软件设计了典型的包含主次任务的试验场景,其中替代型主任务为判断车速,替代型次任务为判断箭头方向。共有87位被试者参与了试验,根据要求做出判断并按键反应;试验将次任务的难度和任务间隔时间作为2个因变量,每个因变量取2种水平,共设计了4组试验,每组试验还包括连续执行主任务和执行次任务之后再执行主任务2种情况。研究结果表明:由次任务转换到主任务后的平均反应时间比持续执行主任务情况下的平均反应时间更长,且二者有显著性差异(??p??<0.01);次任务难度对驾驶人的反应时间有显著影响(??p??=??0.003??);任务间隔时间对驾驶人反应时间的影响不显著,并且次任务难度和任务间隔2个因素没有显著的交互作用;驾驶人在次任务结束之后执行主任务时仍然会受到影响,此外性别、年龄等因素对反应时间也有显著影响。研究结论可用于车载信息系统的优化设计。
In order to study the factors that influencing the speed judgment after finishing a secondary task,and to study how the difficulty of the secondary task and respond clue interval influences the switching cost, a typical experiment scenario based on E??Prime was developed. In the experiment, the driving speed judgment task was selected as the main task, and a typical alternative driving distraction task (arrow direction selection task) was selected as the secondary task. Eighty??seven participants participated in this experiment and made judgments according to the quality. For the experiment, secondary task complexity and task interval were considered as two independent variables, and each variable had two experimental levels. There were four groups of experiments, and each group included two situations, doing two adjacent main tasks and switching to the main task after finishing the secondary task. The results show that the driver??s reponse time for the main task is more after switching from the secondary task to the main task, compared to performing two adjacent main tasks, and there are significant differences (??p??<0.01). The driver??s reponse time for the primary task increased when the secondary task became complex, and there are significant differences (??p??<0.001). When the task interval changed from 200 ms to 2 000 ms, there is no significant effect on the average reponse time for the primary task. There is no significant interaction between the two factors. It still has an influence on the main task after finishing the secondary task. Besides these factors, gender and age also have an impact on the reponse time. The conclusions of this study can provide a reference for the optimal design of in??vehicle information systems. 5 tabs, 7 figs, 30 refs
多聚磷酸及橡胶粉复合改性沥青性能
Properties of composite??modified asphalt with polyphosphoric acid and rubber powder

,魏建国,时松,高建平,段筱娟,程毅
- , 2018,
Abstract: 为研究多聚磷酸(PPA)与橡胶粉复合改性沥青的综合性能,以更好地确定其适用条件。分别采用常规试验及动态剪切流变试验,通过针入度、软化点、延度、针入度比、车辙因子、相位角、复数模量指数等指标,对不同橡胶粉含量及不同PPA掺量的改性沥青进行研究,详细评价PPA及橡胶粉复合改性后的高低温性能、感温性能及短期老化性能。结果表明:复合改性沥青高温性能得到很大提升,软化点提高,抗车辙因子较基质沥青提高了5~20倍;动态剪切流变试验中,在高温高频率条件下,复合改性沥青的储存模量随着频率增加而增大,在中国道路行驶的允许车速范围内,随着车速的增加,改性沥青的弹性性能表现更佳,利于沥青路面的抗车辙作用;掺入PPA及橡胶粉改性对沥青的延度并无改善,且掺量越多,对沥青延度降低幅度越大,低温抗裂性能下降;复合改性后,沥青复数模量指数(GTS)斜率变小,说明感温性能得到提升;对于老化性能来说,掺入PPA能提高沥青老化前后的抗车辙因子,相位角增加的范围也较小,PPA复配橡胶粉改性沥青老化前后高温抗变形能力优于橡胶粉单一改性沥青。综合看来,掺入PPA能有效改善橡胶粉改性沥青的高温性能、感温性能及短期老化性能,其中,掺量(质量分数,下同)1.5%PPA+15%橡胶粉复合改性沥青整体性能相对最佳。
In order to study the comprehensive performance of polyphosphoric acid (PPA) and rubber powder composite modified asphalt and its applicable conditions were investigated. Conventional and dynamic shear rheological tests were conducted, using indicators of the degree of targeting, softening point, ductility, penetration ratio, rutting factor,phase angle, and complex modulus index. Composite??modified asphalts with different contents of rubber powder PPA were studied. The high?? and low??temperature performance, as well as the temperature??sensitive and aging properties, were evaluated in detail. The results show that the high??temperature performance of composite??modified asphalt is significantly improved, the softening point is higher, and the anti??rutting factor is approximately 5 to 20 times higher than that of the matrix asphalt. The deformation of asphalt is smaller under conditions of high temperature and large frequency, which is beneficial to the anti??rutting effect of asphalt,in a dynamic shear rheological test. The elastic property is better under a permissible speed, which is beneficial to the anti??rutting of pavements. However, the addition of PPA and rubber powder does not improve the ductility of the asphalt. The higher the amount of asphalt, the greater the decrease in its ductility. Further, the low??temperature performance of the asphalt decreases. The slope of the complex modulus index (GTS) of the modified asphalt declines, indicating that the temperature sensing performance is improved. The blending of the PPA can upgrade the anti??rutting factor of asphalt aging, lowering the degree of phase angle increase. The high??temperature deformation resistance of asphalt modified with PPA and compound rubber powder is better than that using only modified rubber powder. Therefore, the incorporation of PPA can effectively improve the high?? and low??temperature performance, as well as the temperature??sensitive and aging properties. Among the results, 1.5% PPA+15% rubber powder composite modified
中医扶正方剂玉屏风散的药理研究
易宁,,象华,崔益萍,潘碧霞,王元,谷新平,何新英
中国中药杂志 , 1981,
Abstract: <正>玉屏风散为中医“扶正固表”的名方,源于《世医得效方》一书,主治气虚表弱易感风寒者,已六百余年史。由主药黄芪佐以防风、白术组成。近年来本院附属第三人民医院肾病组用本方“扶正”取得临床疗效,并有免疫指标改善。黄芪影响免疫已有观察,多数认为有增强作用,但也有表现为抑制的。鉴于中医“扶正”涵义,“主要针对辨证选用补益类方药,协调机体气、血、阴、
有毒藻产毒过程中海洋细菌的作用
林伟,
海洋科学 , 2001,
Abstract:
基于弱kerr非线性相互作用的近乎确定性可控量子隐形传态
,
量子电子学报 , 2011,
Abstract: 基于cross-Kerr非线性相互作用,我们提出了一种近似确定性的可控量子隐形传态方案。利用量子非破坏性测量技术较容易地实现了复杂的控制非操作和贝尔态分析过程,这使得此方案比以往使用投影测量的隐形传态方案效率更高,进一步的分析表明方案在现有的实验条件下是切实可行的。
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