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101.
本文介绍了经课题组研发的彩色陶瓷减速标线的特点及应用范围。详细阐述了彩色陶瓷减速标线的视觉效果、陶瓷骨料性能、施工流程以及在湖南衡桂高速公路的应用情况。通过研究、分析和应用,一种既有震动减速又有视觉提醒作用的新型减速标线,具有技术先进性和独创性,有较大的推广应用前景。  相似文献   
102.
含磨粒油润滑工况下磨粒分载量计算   总被引:1,自引:0,他引:1  
建立了等尺寸和不等尺寸、按数量浓度和重量浓度计算磨粒数量的模型和方法,推导了磨粒发生弹、塑性变形情况下磨粒分担载荷量的计算公式,并计算了磨粒分载量随磨粒浓度及尺寸的变化规律,为进一步研究多磨粒效应奠定了基础。  相似文献   
103.
The modern hydrological regime of the Dead Sea is strongly affected by anthropogenic activity. The natural fresh water budget has changed mainly due to the drastic reduction of runoff. Since 1977, the surface level of the Dead Sea has been lowered by an average rate of about 60 cm/year and for the period from 1998 to 2000, the lowering rate has reached about 100 cm/year. As a result of the runoff reduction, the upper layer salinity of the Dead Sea has increased and the gravitational stability of the water body was diminished. Eventually, during the winter of 1978–1979, the lake waters overturned, bringing to an end the long-term stable meromictic1 hydrological regime. The lake entered a new phase in which its hydrological regime switches between holomictic and meromictic regimes, depending on the size of the runoff into the lake (i.e. the amount of precipitation in the lake's watershed). The first holomictic period, 1979–1980, lasted for 2 months only. It was succeeded by a 4-year meromictic period (1980–1983). The second holomictic period lasted for 9 years (1983–1991). The rainy winter of 1991–1992 resulted in an almost 2-m sea level rise. The upper layer with a relatively low salinity was restored and a new meromictic period persisted for 4 years, until winter 1995–1996. During the last meromictic period, the hydrological regime of the Dead Sea was characterized by following long-term trends: the depth of the summer thermocline increased from 12–15 to 25–30 m; the quasi-salinity of the upper layer, initially of about 164 kg/m3, increased rapidly at a rate of about 16–18 kg/m3/year; the quasi-salinity of the deep water, initially of about 235 kg/m3, decreased slowly at a rate of about 0.08–0.10 kg/m3/year (for the sake of comparison, a quasi salinity of 235 kg/m3 is the equivalent of 280‰ “usual” salinity); and the winter minimal temperature of the upper layer, initially of about 16 °C, increased rapidly at a rate of about 2 °C/year. In November 1995, the latest meromictic period of the Dead Sea came to an end. During the present holomictic period, 1996–2000, the hydrological regime of the Dead Sea is also characterized by long-term trends: the quasi-salinity of the entire Dead Sea increased at a rate of about 0.5 kg/m3/year, with practically no decrease during the winters; the temperature of the deep water mass increased with a rate of about 0.25 °C/year; and the period of vertical convection of the entire water column, initially about 3 months, increased at a rate of about 1 week/year. Moreover, we observed that the temperature and salinity of the bottom layer in the deepest part of the Dead Sea raised by about 0.5–0.6 °C and 0.15–0.25 kg/m3 during each holomictic summer.  相似文献   
104.
有限大小神经元细胞膜动作电位的温度效应   总被引:1,自引:0,他引:1  
研究了温度对有限大小神经元细胞膜动作电位的影响.发现随着温度的增加,在相同的时间内神经元产生的脉冲数目有先增加再降低的变化.在中等面积下,平均脉冲间间隔有类似于共振的先降低,达到最小值,再增加的现象.通过计算功率谱以及由功率谱定义的卢因子,很清楚地看到β在某些温度时达到了最大值,产生了相干共振.  相似文献   
105.
结合工程实例 ,介绍复杂条件下半桩在高层建筑基坑支护和桩基工程中的应用  相似文献   
106.
We analyse the choice of mode in suburban corridors using nested logit specifications with revealed and stated preference data. The latter were obtained from a choice experiment between car and bus, which allowed for interactions among the main policy variables: travel cost, travel time and frequency. The experiment also included parking cost and comfort attributes. The attribute levels in the experiment were adapted to travellers’ experience using their revealed preference information. Different model specifications were tested accounting for the presence of income effect, systematic taste variation, and incorporating the effect of latent variables. We also derived willingness-to-pay measures, such as the subjective value of time, that vary among individuals as well as elasticity values. Finally, we analysed the demand response to various policy scenarios that favour public transport use by considering improvements in level-of-service, fare reductions and/or increases in parking costs. In general, demand was shown to be more sensitive to policies that penalise the private car than those improving public transport.  相似文献   
107.
赵骏 《港口科技》2007,(3):29-32
以南通港狼山三期通用散货泊位水下地形整治工程为例,介绍了码头水下地形整治工程的实施方案、工程特点、实施要点及注意事项。水下深潭区采用抛填砂枕方案、水下丁坝拆除后来用平顺抛石护岸的替代方案,实施方案科学合理、施工工艺成熟、技术上过关、护岸效果明显。  相似文献   
108.
内河架空直立式集装箱码头结构计算中的作用效应组合探讨   总被引:12,自引:1,他引:11  
文章中采用单位力法对内河大水位差架空直立式集装箱码头可能出现的荷载工况进行了有限元计算,并采用MATLAB软件编程对计算结果进行分析组合,得到了计算结构各主要构件控制内力的最不利作用效应组合情况,提出了内河架空直立式集装箱码头结构计算的作用效应组合方法。  相似文献   
109.
以审美为核心的音乐教育是21世纪开始的全国音乐教育改革的精髓,基础与立场为重新确立人的感性地位;再次审视什么是“音乐美学”中的“音乐”;强调音乐的特殊性和对音乐审美问题的基本认识.它对大学生幸福感的提升将产生积极作用,根据大学生幸福感的主观性、丰富性、稳定性、整体等四大特点,逐一论述音乐美育对大学生幸福感的影响.  相似文献   
110.
根据一座主桥为三跨(47m 75m 47m)连续刚构桥的悬臂施工过程,计算分析悬臂施工阶段预应力荷载产生的箱梁剪力滞效应,研究该类桥在整个悬臂施工过程中,每个阶段预应力荷载产生的箱梁剪力滞效应,以及一些关键截面剪力滞效应的变化规律;结果表明,在悬臂施工过程中,悬臂预应力束会对箱梁产生正负剪力滞效应,且负剪力滞效应较大。  相似文献   
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