图形文件几何参数的抽取技术

阐述了从图形文件抽取几何参数的技术，即把复杂的内部图形文件转换成外部可读的通用文件．通过对通用文件的结构分析，找出其内在的规律，然后用高级语言进行抽取和加工，将用户所需的几何参数写人数据文件，提供给用户读写，从而达到对图形数据管理的目标．     

LKLR: A Local Tangent Space-Alignment Kernel Least-Squares Regression Algorithm

In the fields of machine learning and data mining, label learning is a nascent area of research, and within this paradigm, there is much room for improving multi-label manifold learning algorithms for high-dimensional data. Thus far, researchers have experimented with mapping relationships from the feature space to the traditional logical label space(using neighbors in the label space, for example, to predict logical label vectors from the feature space's manifold structure). Here we combine the feature manifold's and label space's local topological structures to reconstruct the label manifold. To achieve this, we use a nonlinear manifold learning algorithm to transform the local topological structure from the feature space to the label space. Our algorithm adopts a regularized leastsquares kernel method to realize the reconstruction process, employing an optimization function to find the best solution. Extensive experiments show that our algorithm significantly improves multi-label manifold learning in terms of learning accuracy and time complexity.     

基于CBR与RBR的交通事故责任认定系统研究

文章研究的系统运用辅助决策支持,在事故责任认定中将规则推理与案例推理结合,弥补各自的不足,充分发挥CBR和RBR各自优势,有效促进了事故的处理,从而实现交通事故责任认定工作的公开、公平、便民。     

矩形微细通道内流场的可视化实验研究

以蒸馏水为工质,水溶伊红为着色剂,对水力直径为419.2μm,相对粗糙度为3.86%的矩形不锈钢微槽内流动流态进行了可视化实验研究.经光学显微镜放大后由CCD相机拍摄,得到了不同Re数下矩形微槽内的流型图,同时测量了微槽内的摩擦阻力系数.可视化实验表明随Re数增大,出口段、中间段及入口段依次出现层流向湍流过渡,层流向湍流过渡是渐进的、连续的.摩擦阻力实验表明无论层流区还是过渡区,摩擦阻力系数均高于传统理论预测值,由于转捩提前层流区摩擦阻力系数随Re数增大,与传统理论预测值偏差越大.可视化实验与摩擦阻力实验均表明层流向湍流过渡的临界Re数在1 500左右.     

自主式静压气体轴承实现无究刚度的条件分析

传统的静压气体径向轴承由于低刚度而存在着振动和运动精度不高的问题,为此,作者提出一种自主式气体轴承控制方案,这种新型轴承帅检测轴颈位移的非接触式传感器,驱动轴颈的控制阀及调节整个系统的控制器组成,当有径3种节流控制方案,并得到相应的实现无究刚度的数值解。     

轻质聚合物干粉抹面砂浆抗压强度与抗冻性

外墙抹面砂浆作为建筑物外表层常年受到冻害侵扰,为有效缓解冻害破坏及厘清劣化机理。以空心漂珠作细集料,掺入聚合物干粉与重钙制备不同水灰比的轻质抹面砂浆,通过正交试验,揭示水灰比、可再分散乳胶粉掺量及重钙掺量对抗压强度和抗冻性能的影响规律,并探讨砂浆性能变化的微观机理。结果表明：水灰比对抗压强度影响显著,可再分散乳胶粉掺量次之,重钙掺量影响最小。对于抗冻性能可再分散乳胶粉掺量影响显著,重钙掺量影响最小;在不同养护龄期下,水灰比对抗压强度影响较大,可再分散乳胶粉掺量对抗冻性能影响较大。若将水灰比控制在0.35附近,可再分散乳胶粉掺量与重钙掺量保持在3%以内,虽然抗压强度小幅降低,但抗冻性能优异。综合考虑抗压强度和抗冻性能的实际需求,外墙抹面砂浆的抗冻性能重要程度远大于抗压强度,基于此,可确定干粉抹灰的最优配比为水灰比0.37、可再分散乳胶粉掺量2.8%、重钙掺量3.9%。此外,也可结合实际工作环境与工程要求,设计不同配比的干粉抹灰。     

智能化信息系统对飞行员视觉搜索特性的影响

为探究飞行员使用智能化信息系统的视觉搜索特性,设计以信息系统等级（交互式辅助系统和电子飞行手册）为自变量、以视觉搜索特性（视觉搜索特征和绩效水平）为因变量的对比实验,记录20名航线飞行员在模拟机实验场景中所关注的各人机交互界面的眼动数据,通过统计分析、构建视觉搜索绩效评估模型,反映飞行员视觉搜索特征及绩效水平。结果表明：两组飞行员的注视总持续时间、注视总持续时间占比、注视次数等视觉搜索特征存在显著差异,且随着信息系统智能化等级的提高,飞行员在单发失效和襟翼卡阻故障场景中的视觉搜索绩效水平有效提高且工作负荷降低。由此,验证了信息系统自动化程度的提高在复杂场景下能对飞行员的工作绩效产生正效应,可为驾驶舱人机交互界面的设计、优化及迭代提供理论参考,保证飞行安全。     

Interlayer engineering of molybdenum disulfide toward efficient electrocatalytic hydrogenation

Electrocatalytic hydrogenation (ECH) enables the sustainable production of chemicals under ambient condition;however,suffers from serious competition with hydro...     

Comparison of Travel Mode Choice Between Taxi and Subway Regarding Traveling Convenience

In this study, we investigate travel mode choice behavior between taxi and subway with an emphasis on the influence of traveling convenience. In the first stage, we examine the Origin-Destination(OD) points of Beijing taxi trips and compare these locations with the respective nearest subway station. Statistics reveal several interesting conclusions. First, for approximately 24.89% of all trips, no convenient subway connections exist between the OD pairs. As such, a taxi becomes the only viable choice. Second, for 80.23% of the remaining 75.11%of trips(equivalent to 60.26% of all trips), access distance from either the origin or the destination to the nearest subway station is greater than 500 meters. This phenomenon indicates that walking distance plays an important role in travel mode choice. In the second stage, we examine groups of taxi trips with similar travel distances and travel times to reveal common features. We establish a preference rule in terms of travel distance and travel time.This determines whether an individual driver will take a taxi or the subway, using a pairwise comparison-based preference regression model. Tests indicate that more than 95% of taxi trips can be correctly predicted by this preference rule. This conclusion reveals that traveling convenience dominates the travel model choice between taxi and subway. All these findings shed light on the factors that influence travel mode choice behavior.     

一种研究管道对电液伺服系统动态性能影响的综合分析法

以分布参数法研究管道动态特性对液压控制系统性能的影响,将连接管道对系统的影响归入伺服阀线性化流量方程中,提出了处理电液控制系统中连接管道的一和中综合分析法,大大简化了控制系统的动态数学模型,为进一步分析含有连接管道的液压控制系统提供了更为科学的理论基础。