Evaluating the feasibility of a passive travel survey collection in a complex urban environment: Lessons learned from the New York City case study

The combination of increasing challenges in administering household travel surveys and advances in global positioning systems (GPS)/geographic information systems (GIS) technologies motivated this project. It tests the feasibility of using a passive travel data collection methodology in a complex urban environment, by developing GIS algorithms to automatically detect travel modes and trip purposes. The study was conducted in New York City where the multi-dimensional challenges include urban canyon effects, an extreme dense and diverse set of land use patterns, and a complex transit network. Our study uses a multi-modal transportation network, a set of rules to achieve both complexity and flexibility for travel mode detection, and develops procedures and models for trip end clustering and trip purpose prediction. The study results are promising, reporting success rates ranging from 60% to 95%, suggesting that in the future, conventional self-reported travel surveys may be supplemented, or even replaced, by passive data collection methods.     

In situ absorption and metabolism of stilbene glycoside in rat

Stilbene glycoside (TSG) has been shown to have many beneficial properties. It is therefore essential to understand the absorption and metabolism of TSG in detail. We determined the recovery of TSG and its metabolites (TSG sulfate/glucuronides) in rat gastric contents, gastric mucosa, portal vein plasma, celiac arterial plasma, bile, and urine after administration of 15mg of TSG in 0.5mL physiological saline or incubation for 20min in situ in the stomach of rats. Within 20min, (64.0±9.8)% of the administered TSG disappeared from the stomach; later, TSG was recovered in both free and conjugated forms in plasma and bile, but not in urine. On the other hand, only free TSG was detected in the gastric contents and mucosa; it was also detected in the portal vein plasma as (48.1±3.5)% of the total TSG (all forms of TSG). However, the proportion of free TSG in the celiac arterial plasma and bile decreased to 4%-10%. In addition, the proportion of free TSG to total TSG in the liver microsome incubation mixture after TSG was incubated in liver microsome at 37℃ for 30min was very low [(10.6 ± 2.6)%]. These results indicate that TSG could be quickly absorbed from the rat stomach, conjugated in liver and excreted in bile. Such novel information would be helpful for the use of TSG as a beneficial natural product which may improve its proposed efficacy in preventing chronic diseases.     

动车组转向架构架的有限元分析及虚拟装配实现

利用I-DEAS和3ds MAX软件对某型号动车组转向架构架进行三维实体建模、虚拟装配动画演示,应用有限元方法对转向架的构架结构及载荷性能进行了研究,计算结果表明其强度满足设计要求。     

满足欧洲Ⅰ排放法规的车用直喷式柴油机燃烧系统的研究

本文针对自然吸气式车用6110直喷式柴油机,对燃油喷射系统、燃烧室形状、进气涡流比和机械离心喷油提前规律进行优化匹配研究,获得了满足欧洲Ⅰ排放法规的燃烧系统参数。     

石灰稳定类沥青路面结构模式分析

通过对郑州市常用的石灰稳定类沥青路面的裂缝调查分析、石灰稳定土的强度分析、破坏机理分析 ,阐述了郑州市这种道路结构的弊端     

TITAN423摊铺机熨平板水平受力框架的设计

针对TITAN423摊铺机在12m宽幅作业时的情况，通过对结构的分析，给出了一种合理的改进措施，实践征明效果良好。     

神经网络控制汽油机空燃比的研究

结合发动机空燃比的控制特征，研究了一种能自适应补偿喷油量的CMAC控制器。介绍了其自适应补偿算法——学习—补偿法。通过采用台架试验数据加随机扰动数据并用MATLAB对CMAC进行训练和仿真，获取了控制器参数，验证了控制器的学习能力、鲁棒性和控制精度。     

蛋白激酶C活性在脑血管痉挛过程中的变化

目的探讨蛋白激酶C(PKC)活性在脑血管痉挛(CVS)过程中的变化及其意义。方法日本大耳白兔25只,随机分为对照组(5只)与模型组(CVS组,20只),CVS组又分为1、3、5、8 d组,每组5只。采用枕大池2次注血法建立脑血管痉挛动物模型,血管造影观察基底动脉(BA)痉挛,放射免疫法和放射性同位素标记蛋白激酶测定法动态测定血浆内皮素和兔BA管壁PKC活性。结果枕大池2次注血法可以成功构建脑血管痉挛模型,是一种简便、可靠的方法;模型组血浆中内皮素含量和BA壁内PKC的活性均明显升高,且在5 d组达到峰值,与对照组相比差异有统计学意义(P<0.05)。结论PKC活性与CVS的严重程度呈正相关。     

不同特征遥感图像在江滩钉螺孳生地监测中的应用

目的　探讨由LandsatETM +遥感图像组成的特征图像在江滩钉螺孳生地监测中的应用。方法　对以LandsatETM +图像组成的 3种特征图像进行非监督分类 ,并通过现场勘察和计算类别间分离度对分类结果进行评价。结果　以ETM的第 2、3、4波段组成的ETM2 34伪彩色复合图像的分类识别效果比较好 ,能有效地将江滩芦苇、梭叶草和杂草滩等识别出来 ,有助于江滩钉螺孳生地的监测。结论　遥感图像非监督分类能有效识别江滩地表植被的分布而用于钉螺孳生地的监测 ,但应根据研究地区的实际情况选择合适的特征图像。     

轿车地毯热力塑性成形性能的尺寸效应研究

以单向拉伸试验研究了轿车地毯不同宽度尺寸试样的热力塑性成形性能,试验发现轿车地毯材料的塑性成形性能具有尺寸效应。分析了轿车地毯材料的强度、塑性和断裂功等成形性能受尺寸的影响程度。试验结果表明,宽度为50mm的试样可以作为轿车地毯材料基本力学性能测试的统一标准,能较稳定地反映轿车地毯的基本力学性能。