正交优化设计在副连杆强度研究中的应用

作者按正交试验法的原理编制了正交优化程序。对某柴油机副连杆,以衬套同连杆体的过盈度,两端到杆身连接圆弧的半径及杆身工字筋的壁厚作为设计变量;以最大破坏应力点的应力值同副连杆重量的乘积作为目标函数;在连杆尺寸只作较小变动,不影响原加工流水线条件下进行优化。 优化后,最大破坏应力在活塞端下降9.8％;在副销端下降5.8％;而副连杆的重量也减少了2.1％。 只要改变设计变量、约束条件和目标函数,本计算方法也能对其它零部件进行优化和适应其它优化问题。     

拱桥内力计算分析程序开发研究

以拱桥经典计算理论为基础,应用Visual Basic语言开发了一套专门用于普通上承式和中承式拱桥内力计算的分析程序。该程序包含了"85"规范和"04"规范两种荷载等级,可以开展拱轴系数优化、恒载、活载和附加内力计算,并自动完成荷载组合和承载力验算。通过算例结果表明,所开发的专用程序具有较高的计算精度,且操作方便,实用性强。     

现代信息技术在桥梁结构无损检测中的应用

桥梁结构无损检测与评估技术的研究是当前国际上土木工程领域的难点和热点。文章结合信息技术发展的特点,探讨和总结了现代信息技术在桥梁结构无损检测与评估上的应用与发展,并对相关问题进行了讨论。     

Short-term shift setting and manpower supplying under stochastic demands for air cargo terminals

A good air cargo terminal manpower supply plan helps terminals deal efficiently with their cargos and reduces their operating costs. To design a good air cargo terminal manpower supply plan, a terminal has to consider not only its operating costs, but also the uncertainty of the manpower demand in actual operations. However, most air cargo terminals in Taiwan currently depend on staff experience with a fixed demand when establishing the manpower supply plan, which is neither effective nor efficient. We have developed two stochastic-demand manpower supply plan models for air cargo terminals that can resolve stochastic demands occurring in practice. The objectives of both models are to minimize the total man-hour cost, subject to the related operating constraints. The models are formulated as integer/mixed integer linear programs. To evaluate the two stochastic-demand models under stochastic demands, we have also developed two deterministic-demand manpower supply plan models, by suitably modifying two stochastic-demand models, respectively, and an evaluation method. Here, we perform a case study using real operating data from a Taiwan air cargo terminal. The preliminary results are good, showing that the models could be useful for planning air cargo terminal manpower supply.

双层圆柱壳结构减振设计及模型试验研究

为降低双层圆柱壳动力舱结构振动辐射噪声,对双层圆柱壳进行了减振设计和模型试验研究.基于环肋结构增抗原理和模态振动控制理论,提出了非均匀阻抗增强环肋结构形式;为减小双层壳间振动波的传递,将阻振质量和粘弹性夹层引入到实肋板结构设计中,采用波动理论分析了复合阻波特性.联合应用非均匀阻抗增强环肋和复合阻波肋板设计了一种双层壳模型,并开展了空气中两端简支和水下悬浮激振试验;将设计模型测试结果和数值仿真计算结果与基准模型进行了分析比较.结果表明:设计模型较原结构振动明显减弱,具有较好的减振效果,验证了双层壳结构减振设计的有效性.     

Design of income-equitable toll prices for high occupancy toll lanes in a single toll facility

Income inequity potentially exists under high occupancy toll (HOT) lanes whereby higher-income travelers may reap the benefits of the facility. An income-based multi-toll pricing approach is proposed for a single HOT lane facility in a network to maximize simultaneously the toll revenue and address the income equity concern, while ensuring a minimum level-of-service on the HOT lanes and that the toll prices do not exceed pre-specified thresholds. The problem is modeled as a bi-level optimization formulation. The upper level model maximizes revenue for the tolling authority subject to pre-specified upper bounds on tolls. The lower level model solves the stochastic user equilibrium problem. An agent-based solution approach is used to determine the toll prices by considering the tolling authority and commuters as agents. Results from numerical experiments indicate that a multi-toll pricing scheme is more equitable and can yield higher revenues compared to a single toll price scheme across travelers.     

控制器样机快速开发在实时测试中的应用

提出一种基于两个目标硬件的控制器样机快速开发的方法,其中一个目标硬件用于执行控制器功能,另外一个则仿真被控对象。它能够进行实时测试,有效检测控制器功能的实时特性。设计中的绝大多数异常或错误能够被准确检测和及时修正。这种方法有效提高了设计的控制器功能的可靠性,缩短了开发周期。它已被用于一款新型变速器控制单元的设计开发过程,证明了其有效性。     

三峡库区巴东组地层超长桩桩侧摩阻力的自平衡试验

宜（昌）万（州）高速公路孙家沟大桥试桩工程中,采用自平衡试桩法对人工挖孔灌注桩承载力进行测试。实践表明该测试法在山岭条件下具有无可比拟的优势,因此在山岭重丘区桥梁桩基中具有广阔的应用前景。     

Software Testing Method Based on Model Comparison

A model comparison based software testing method (MCST) is proposed. In this method, the requirements and programs of software under test are transformed into the ones in the same form, and described by the same model describe language (MDL).Then, the requirements are transformed into a specification model and the programs into an implementation model. Thus, the elements and structures of the two models are compared, and the differences between them are obtained. Based on the diffrences, a test suite is generated. Different MDLs can be chosen for the software under test. The usages of two classical MDLs in MCST, the equivalence classes model and the extended finite state machine (EFSM) model, are described with example applications. The results show that the test suites generated by MCST are more efficient and smaller than some other testing methods, such as the path-coverage testing method, the object state diagram testing method, etc.     

公路工程测量放线CASIO fx-4850P实用程序

介绍了自行设计、使用的公路工程测量放线的计算大地坐标的CASIO fx-4850P实用程序,供广大同仁参考使用,服务于我国的快速发展的公路建设。