特种装备项目的节能评估方法研究

特种装备的购置及改造项目属于固定资产投资范畴,在审批环节中应进行节能审查。本文以科学考察船为例,基于分析科学考察船与其他类固定资产的不同,阐述了科学考察船建设方案的节能评估、能源消费种类及能耗测算方法,并就评估过程中存在的问题提出了相关建议。     

能耗吸收装置在城市轨道交通系统中的应用

介绍了城市轨道交通系统能耗吸收装置的原理和组成,分析了能耗吸收装置的能量吸收过程和系统控制方式,总结了能耗吸收装置运用过程中的故障种类、故障现象及相应的故障解决方法。     

滑差对贝氏体钢轨材料磨损行为的影响

通过对磨试验研究接触应力相同时贝氏体钢轨的磨损率、表面粗糙度、硬度,并结合扫描电镜观测到的磨损表面和剖面的形貌特征,分析不同滑差条件下贝氏体钢轨的磨损行为特征和变化规律.结果表明:接触应力为500 MPa条件下,贝氏体钢轨磨损率随滑差的增大而显著增大,滑差由2%增大到10%时磨损率增大了8倍;小滑差条件下的贝氏体钢轨表面较光滑,有少量疲劳裂纹,以滚动接触疲劳磨损为主;大滑差条件下表面粗糙,有疲劳裂纹、剥落坑和表面划擦痕迹,更接近滑动磨损;增大滑差可导致磨损表面加工硬化率偏大;增大滑差对贝氏体钢轨表面的滚动接触疲劳裂纹在深度方向的扩展几乎无影响,且对塑性变形层厚度影响不明显;大滑差可引发亚表面次表层裂纹.     

Factors affecting public transportation usage rate: Geographically weighted regression

As the number of private vehicles grows worldwide, so does air pollution and traffic congestion, which typically constrain economic development. To achieve transportation sustainability and continued economic development, the dependency on private vehicles must be decreased by increasing public transportation usage. However, without knowing the key factors that affect public transportation usage, developing strategies that effectively improve public transportation usage is impossible. Therefore, this study respectively applies global and local regression models to identify the key factors of usage rates for 348 regions (township or districts) in Taiwan. The global regression model, the Tobit regression model (TRM), is used to estimate one set of parameters that are associated with explanatory variables and explain regional differences in usage rates, while the local regression model, geographically weighted regression (GWR), estimates parameters differently depending on spatial correlations among neighbouring regions. By referencing related studies, 32 potential explanatory variables in four categories, social-economic, land use, public transportation, and private transportation, are chosen. Model performance is compared in terms of mean absolute percentage error (MAPE) and spatial autocorrelation coefficient (Moran’ I). Estimation results show that the GWR model has better prediction accuracy and better accommodation of spatial autocorrelation. Seven variables are significantly tested, and most have parameters that differ across regions in Taiwan. Based on these findings, strategies are proposed that improve public transportation usage.     

基于磁处理法的隧道永磁体排水管防结晶试验

为预防隧道排水管结晶堵塞，提出永磁体排水管关键技术指标，通过自制的永磁体排水管开展室内试验和现场试验，研究磁场强度、流量、磁体布置间距对永磁体排水管内结晶的影响，根据不同条件下结晶物的质量变化和SEM图像进行试验分析。结果表明： 1）磁场强度为0.1~0.3 T时永磁体排水管具有较好的防结晶效果，磁场强度超过0.2 T后防结晶效果逐渐降低，当磁场强度为0.4 T时永磁体排水管内结晶量反而大于普通排水管； 2）随着试验管段内溶液流量增大，永磁体排水管的防结晶效果增强，但当流量超过450 mL/s之后，防结晶效果不再随流量增大而增强； 3）经永磁体处理后，管道内的结晶物由规则的立方体形状转变为粗糙松散的不规则体，由硬质块状转变为粉末状，有从方解石向文石、球霞石转化的趋势； 4）随着管道永磁体布置间距减小，管道内最终结晶量呈下降趋势，在10、40、70 cm 3种永磁体布置间距中，最佳布置间距为40 cm。     

Integrated design optimization of spar floating wind turbines

A linearized aero-hydro-servo-elastic floating wind turbine model is presented and used to perform integrated design optimization of the platform, tower, mooring system, and blade-pitch controller for a 10 MW spar floating wind turbine. Optimal design solutions are found using gradient-based optimization with analytic derivatives, considering both fatigue and extreme response constraints, where the objective function is a weighted combination of system cost and power quality. Optimization results show that local minima exist both in the soft-stiff and stiff-stiff range for the first tower bending mode and that a stiff-stiff tower design is needed to reach a solution that satisfies the fatigue constraints. The optimized platform has a relatively small diameter in the wave zone to limit the wave loads on the structure and an hourglass shape far below the waterline. The shape increases the restoring moment and natural frequency in pitch, which leads to improved behaviour in the low-frequency range. The importance of integrated optimization is shown in the solutions for the tower and blade-pitch control system, which are clearly affected by the simultaneous design of the platform. State-of-the-art nonlinear time-domain analyses show that the linearized model is conservative in general, but reasonably accurate in capturing trends, suggesting that the presented methodology is suitable for preliminary integrated design calculations.     

Simplified buckling-and-contact-based expansion method for assessment of crashworthiness of double-hulled ship structure

Ship-to-ship collision events can have severe consequences such as loss of life and environmental degradation. For this reason, modern ship designs are required to incorporate a double-hulled structure to prevent inner-hull damage from such events. Using the experimental or numerical method to analyze the crashworthiness of double-hulled ship structures entails much effort, for which reason neither method is easy to adopt at the early design stage. In this paper, an existing simplified method called Ito's method is improved by a new buckling-and-contact-based expansion method. This method can be applied to double-hulled-structure or outer-hull-local-rupture failure mode. The perpendicular bow-to-side collision scenario is assumed for a conservative estimation of damage to a double-hulled structure. The method was verified in the present study by numerical ship collision simulations of several cases. The results for the buckling-and-contact-based expansion method and numerical simulation were similar for a blunt shape of striking body but different for a sharp shape.     

厚壁球壳的杂交／混合有限元分析

本文对８一节点四边形轴对称杂交／混合元ＡＸＨＭ１６进行了系列考核：（１）考查ＡＸＨＭ１６是否含有零能变形模式，以查明它的含秩状况；（２）通过受内压作用的厚壁球壳考题，观察ＡＸＨＭ１６的转轴不变性和其它性能表现。事实表明：ＡＸＨＭ１６满足单元合理足秩的必要条件和充分条件，不含零能变形模式，单刚合足秩。数值考核表明：ＡＸＨＭ１６具有很好的位移精度和应力精度，对坐标转轴的敏感程度并不明显，且在近乎相同的     

输卵管复通200例临床分析

本文分析了200例绝育术后施行输卵管吻合术妇女的妊娠情况及影响因素。手术对象年龄为24～41岁,距原绝育手术时间0.5～12年不等,随访的194例中妊娠178例,异位妊娠1例,妊娠率为91.7％。本文对显微外科技术复通输卵管的修复技术,注意事项,支架使用及去留,避孕期限,输卵管吻合部位,修复后输卵管长度与妊娠的关系等问题进行了讨论。     

定时/计数初值求取公式的修正

本文推导了定时/计数初值求取公式,指出利用求补公式计算定时/计数初值的错误。