矸石脱介筛降噪治理

矸石脱介筛担负着排矸及回收磁铁矿粉的作用，原振动筛因噪声指标严重超标造成诸多问题，通过降低电机转速、采用激振装置，使用新型耐磨材料筛板等降噪措施，满足生产需求，工作环境改善，维修工作量降低，具有明显的经济效益和社会效益。     

打印式旋浆测流仪的简化改装

改变打印式旋浆测流仪浅路，去除复杂的电路控制、数据处理及打印功能，改为仪器自动报警，人工记数记时，手工计算，使测流更简单方便，工作更可靠，更适应野外工作的需要。     

我国机动车排放标准及检测方法简述

根据"新车新标准,老车老标准"的原则,双怠速法将是汽油车基本检测方法,简易工况法在全国范围内分步实施,柴油车将逐步采用不透光烟度计的测量方法.同时介绍了国外相关标准及检测方法.     

L6-M Al的超塑性工艺的实验研究

依拟定之正交实验方案，主要探讨工艺因素成形温度(T)，气体速度(V)，模具圆角半径(R)对铝板(L6-M)超塑性工艺性能的影响。经研究发现铝材(L6-M)在超塑性成形时，三个主要工艺因素对其影响的强弱顺序为成形温度(T)；气体速度(V)；模具圆角(R)，且都影响显著。     

镉、铅在玉米幼苗中的积累和迁移--X射线显微分析

用扫描电镜-X射线能谱仪及原子吸收分光光度计,测定经不同浓度镉、铅处理的玉米根、叶中镉、铅的积累。结果表明,铅的积累为皮层>中柱;木质部薄壁组织>导管。镉则相反。铅主要以非共质体途径在根内横向迁移,镉主要以共质体途径在根内横向迁移。原于吸收分光光度计测定表明,镉、铅主要在玉米根内沉积,镉铅复合作用促进了玉米根叶对镉、铅的吸收,镉比铅更易为玉米吸收且更易从根向叶迁移。     

城市雾天单个矿物颗粒物理和化学特征

应用场发射扫描电镜(FESEM)和带能谱的扫描电镜(SEM-EDX)对北京冬季雾天和正常天气下收集的4个样品进行研究.雾天中矿物颗粒的数量-粒度分布的峰值出现在0.1～0.3 μm和1～2.5 μm之间,并且发现雾天出现的二次矿物颗粒的数量百分含量(4.67%)高于正常天气条件(0.12%).单个矿物颗粒的EDX能谱显示,雾天和正常天气中单个矿物颗粒的主要化学成分有一定的差别,尤其是S元素.矿物颗粒分为9种不同类型:"富Si"、"富Ca"、"富S"、"富Fe""富Mg"、"富Al"、"富Ti"、"富K"和"富Cl",其中雾天"富Ca"中55%的颗粒含有Ca(50%±1.2%)和S(37%±1.6%),"富S"中72%的颗粒含有S(44%±1.5%)和Ca(33%±2%),说明了雾天中绝大部富集S的颗粒物中同时富集Ca,这在一定程度上说明了北京市大气中这些含Ca的碱性矿物对雾水酸性有一定的缓冲作用.雾天样品中S/Ca的平均比值为6.11,如果以冬季正常天气条件下S/Ca的均值0.73为背景值,雾天中S/Ca的比值是冬季正常天气的8倍,可见雾天中颗粒物表面的硫化现象相当严重,同时也显示出雾天SO2向硫酸盐的转化率比较高.     

Identifying crash propensity using specific traffic speed conditions

INTRODUCTION: In spite of recent advances in traffic surveillance technology and ever-growing concern over traffic safety, there have been very few research efforts establishing links between real-time traffic flow parameters and crash occurrence. This study aims at identifying patterns in the freeway loop detector data that potentially precede traffic crashes. METHOD: The proposed solution essentially involves classification of traffic speed patterns emerging from the loop detector data. Historical crash and loop detector data from the Interstate-4 corridor in the Orlando metropolitan area were used for this study. Traffic speed data from sensors embedded in the pavement (i.e., loop detector stations) to measure characteristics of the traffic flow were collected for both crash and non-crash conditions. Bayesian classifier based methodology, probabilistic neural network (PNN), was then used to classify these data as belonging to either crashes or non-crashes. PNN is a neural network implementation of well-known Bayesian-Parzen classifier. With its superb mathematical credentials, the PNN trains much faster than multilayer feed forward networks. The inputs to final classification model, selected from various candidate models, were logarithms of the coefficient of variation in speed obtained from three stations, namely, station of the crash (i.e., station nearest to the crash location) and two stations immediately preceding it in the upstream direction (measured in 5 minute time slices of 10-15 minutes prior to the crash time). RESULTS: The results showed that at least 70% of the crashes on the evaluation dataset could be identified using the classifiers developed in this paper.     

长隧道韵律型视觉环境设计研究

采用心理物理试验分析公路隧道内部视觉环境对驾驶员行车安全的影响,将E-prime 2.0软件与仿真驾驶模拟器相结合,对驾驶员在隧道内长时间行车中的速度判断准确率及反应时间两个指标进行分析,提出了利用标志标线构建公路隧道内韵律型标线系统的改善措施,以改善隧道内视觉环境,并利用数理统计方法及Logistics拟合分析对设计方案进行评价。结果表明:1)公路隧道内韵律型标线系统能提升隧道内驾驶员的速度判断准确率3.33%~11.66%;2)普通公路隧道场景中,被试者反应时间与隧道内行车时间存在显著关系,公路隧道内韵律型标线系统的场景中,反应时间与隧道内的行车时间没有显著关系,能有效缓解视觉疲劳现象;3)被试者反应时间的增加同时受隧道内视觉环境与行车时间的影响。公路隧道内韵律型标线系统能有效提高驾驶员的反应时间,适用于行驶速度为80 km/h、大于1 333 m的隧道。     

Experimental analysis of food detection in capuchin monkeys: effects of distance, travel speed, and resource size

Knowing how far away animals can detect food has important consequences for understanding their foraging and social behaviors. As part of a broader set of field experiments on primate foraging behavior, we set out artificial feeding platforms (90 × 90 cm or 50 × 50 cm) throughout the home range of one group of 22 brown capuchin monkeys, at sites where they had not seen such platforms previously. Whenever the group approached such a new platform to within 100 m, we recorded the group's direction and speed of approach, and the identity and distance from the platform of the group member that detected the platform or came closest to it without detecting it. We used logistic regression on these data to examine the effects of group movement speed, platform size and height, and focal individual age and sex on the probability of detecting the platform as a function of distance. Likelihood of detecting a platform decreased significantly at greater distances – the probability of detecting a platform reached 0.5 at 41 m from the group's center and 25.5 m from the nearest group member. These results show that detectability of platforms by the entire group (9 adults, 13 juveniles) was less than twice that for single group members. Detectability at a given distance decreased severely as the group moved faster; at their fastest speed, individuals had to approach a platform to within less than 10 m to find it. The large platforms were significantly more likely to be detected than the small ones, suggesting that increased use of larger food patches by wild primates may not necessarily reflect foraging preferences. Received: 20 May 1996 / Accepted after revision: 5 April 1997     

石河子市大气中氮氧化物与气象条件的关系

用实测数据分析了石河子市大气中ＮＯｘ与气温，湿度和风速等气象因子的关系，得出结论是气温升高，风速增强，使大气中ＮＯｘ浓度值降低，相对湿度在７０％～８０％之间，其ＮＯｘ浓度较高，为此，气象条件诸如水平风速，大气温度，湿度和大气层结构的稳定与否均大对气污染物浓度产生重要影响。