液压油缸中密封套的泄漏问题

文章描述了密封试验方法,回顾了一般允许的泄漏程度,指出了现代密封设计所能达到的地步,评价了用以推测泄漏情况的理论关系,并论述了加剧泄漏的某些因素。     

AMAZON寄来UPS

我是amazon.com和许多indie labels的常客,但自拟命题来采购CD还是头一次,而且用了运费最贵的加急UPS来决速获取它们。我喜欢追踪它们到来的踪迹,从肯塔基的LEXINGTON或是LOUISVILLE,又或者是阿拉斯加的ANCHORAGE,经停韩国仁川机场集合起来,用时共5天,     

东风汽车排蓝白色烟析因

一辆东风EQ1108G汽车，行驶中排出蓝白色的烟，而连续踩加速踏板，排气管便出现大量的黑烟。先想到是否烧机油。进行常规检查发现：曲轴内机油面高低合适（刚换）；活塞环磨损不大，弹力足够，安装方向也正确；气门杆与气门导管的磨损也不大；基本排除了窜机油的可能。就在此时，突然发现，在拆下的空气滤清器和废气涡轮增压器的连接管有机油流出。经过进一步检查，原来不正常的排烟是由废气涡轮增压器转子轴密封环和密封套破损而漏出的润滑油造成的。更换废气涡轮增压器的密封环和密封套后排气恢复正常。     

Application of a mixed DEA model to evaluate relative efficiency validity

Data envelopment analysis （DEA） model is widely used to evaluate the relative efficiency of producers. It is a kind of objective decision method with multiple indexes. However, the two basic models frequently used at present,the C^2R model and the C^2GS^2 model have limitations when used alone ,resulting in evaluations that are often unsatisfactory. In order to solve this problem, a mixed DEA model is built and is used to evaluate the validity of the business efficiency of listed companies. An explanation of how to use this mixed DEA model is offered and its feasibility is verified.