Shape Optimization of Elliptical Road Containers Due to Liquid Load in Steady-State Turning

A numerical analysis of liquid load in elliptical road containers undergoing a steady-state turning manoeuvre is presented for containers of unrestricted size and for containers of fixed capacity. The liquid load is expressed in terms of the horizontal and vertical forces and the overturning moment created by these forces around the middle bottom point of the container. The moment is obtained by integrating the liquid free-surface equation and using numerical calculation of the resulting expressions. An optimization study with an objective to minimize the peak overturning moment is performed on containers of fixed capacity to identify the optimal height/width ratio of the container. The results of this investigation being of a general nature, i.e. with no restriction for an application, are particularly intended for road tankers under a steady turning manoeuvre, where they can be applied with high degree of accuracy.     

Benthic community patterns reflect water column processes in the Northeast Water polynya (Greenland)

Benthic community patterns were investigated in the Northeast Water polynya (Greenland) during the summers of 1992 and 1993 to elucidate to what extent the bottom fauna is influenced by the dynamics of the overlying water. Five different fractions of the benthos (foraminiferans, nematodes, polychaetes, peracarid crustaceans, and epibenthic megafauna), ranging in average adult body size over 6 orders of magnitude (from about 100 μm to about 10 cm), were sampled quantitatively at 69 stations in water depths from 40 to 515 m. Total abundances of nematodes, polychaetes and peracarid crustaceans were found to be primarily correlated with parameters characterizing the potential benthic food supply (water column pigment and nitrate concentrations, sediment bound pigments and sediment biological activity), whereas abundances of foraminiferans and megabenthos were largely associated with seabed properties. Four benthic zones were distinguished by separately analyzing the faunistic composition and distribution of the five community fractions for Ob Bank, Western Westwind Trough, Eastern Westwind Trough, and Belgica Trough. This pattern was shown principally to reflect pelagic regimes differing in surface water hydrography, ice cover and euphotic productivity. This is the first time that a synoptic study of several benthic community portions spanning such a range in sizes and life styles has been performed in a polar shelf ecosystem. Our results indicate that abundances as well as composition of Arctic benthos are largely influenced by mesoscale pelagic processes, and thus provide further evidence for the importance of the benthic-pelagic coupling in high latitude seas.     

让科学发挥作用

在制药行业同生物、化学及药理学学术研究之间，有许多相互作用和相互结合点。在过去20年中，技术转让过程已经成为一个小行业，利用科学、合同法、专利法及商业等多种技巧。如今，西方主要学术机构积极保护它们的知识产权并将其授权给工业行业：这使研究所及科学家们在财政上获益，在技术开发领域创造经济发展，为大多公司渴望的新发明提供保护。     

In-plane Dynamics of Tires on the Road Based on an Experimentally Verified Rolling Ring Model

The dynamic behavior of tires rolling on the road is predicted based on a ring model that is experimentally verified to well represent a real tire. The road contact is kinematically represented by two displacement constraints, one in radial and one in tangential direction. The displacement constraints are enforced via the receptance theory. The receptance matrix developed for the rolling tire is found to be Hermitian. Numerical results show that the natural (or eigen-) frequencies of the rolling tire with road contact are, as expected, higher than those of the tire with no contact. The influence of the rotating speed to the eigen-frquencies of the tire is also shown. Analytic expressions for the mode shapes of a rolling tire with ground contact are derived.     

Intra-Platoon Collision Behavior during Emergency Operations

This paper presents current research regarding intra-platoon collision dynamics for rapid decelerations. Measures of ride quality and impact severity are introduced to allow comparisons between different collision scenarios. In this study, the disturbance input to the platoon is assumed to be a rapid braking of the lead vehicle. Several deceleration rates are used to assess the overall platoon behavior and the effect of the intra-platoon collisions on the platoon passengers. The role of the desired headway spacing on preventing the occurrence of intra-platoon collisions and improving rider comfort is discussed.     

SS4B型电力机车（3）——微机控制系统

ＳＳ４Ｂ型电力机车微机控制系统是在ＳＳ４型００３８号机车和ＳＳ８型机车的基础上研制的，文章介绍了ＳＳ４Ｂ型电力机车微机控制系统的特点、功能和主要参数以及对原有微机控制系统所作的改进。     

EHF病毒在传代鸡胚上的实验观察

本文报道了用已知EHFV seoul株接种9～10d龄鸡胚后鸡胚出现严重局限的出血斑;ELISA试验显示感染鸡胚尿囊液和对照鸡胚尿囊液OD值之比>2.1;免疫荧光试验在感染鸡胚心、脑、肺、肝、肾组织印片细胞浆内可见不同程度荧光颗粒。     

我国重型车用汽油机排放现状分析及试验方法

对我国实施重型车用汽油机排放标准后的部分典型机型的排放做了统计和相关分析；比较了国内外重型汽油机排放标准和试验方法。通过对化油器机型和电喷加三效催化机型的排放测试结果的分析，论及我国重型汽油机的排放控制技术路线，提出了在用重型化油器车的污染治理和控制问题。最后，针对我国现行9工况标准的试验限值和试验方法提出了一些观点。     

模糊自整定PID参数控制器及其在汽车测试设备中的应用

在汽车的控制及测试设备中，广泛使用常规的ＰＩＤ控制器，由于它不具备在线整定ＰＩＤ参数的功能，因此在参数时变较大的系统，其性能难以满足要求。为此本文应用模糊控制技术实现了ＰＩＤ控制器的参数在线自整定，获得了比较理想的效果。本文以汽车传动轴试验台为例，详细地阐述了模糊控制器的设计原理及计算机软件设计方法。     

净化消声器压力损失计算方法

本文综合运用流体力学、热力学及化学有关理论,对柴油机用的净化消声器的压力损失算法进行推导及试验验证,为在净化消声器设计阶段预测净化消声器对发动机性能的影响提供了可用的手段。