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- 小型拖拉机发动机烧瓦的原因及防护措施
- 作者：王春华 来源：农机质量与监督 年份：2013 数据类型 ：期刊 关键词： 防护措施 发动机温度 农机具 烧瓦现象 连杆轴承 使用维修 小型拖拉机 故障 发动机工作 农业机械化水平
- 描述：作为小型拖拉机的核心构件之一,最常见的故障是启动困难或不能启动,烧瓦是小型农机具发动机工作中经常遇到的故障,它是发动机曲轴轴承和连杆轴承的瓦片合金发生熔化脱落,是一种具有破坏性的粘连磨损。农民朋友迫切需要了解一些小型农机具的知识,现将一些适合农村使用的小农机具,如拖拉机等的使用维修知识介绍给大家。
- 拖拉机发动机烧瓦的原因及防护措施
- 作者：王春华 来源：现代农业装备 年份：2013 数据类型 ：期刊 关键词： 防护措施 烧瓦 机油管 曲轴轴承 拖拉机发动机 连杆轴承 核心构件 摇转 金属屑 农业机械化水平
- 描述：随着农业机械化水平的提高,拖拉机在农村得到了越来越广泛的应用。作为拖拉机核心构件之一的发动机,最常见的故障是启动困难或不能启动,而烧瓦也是发动机常遇到的故障。烧瓦是一种具有破坏性的粘连磨损,是发动机曲轴轴承和连杆轴承的瓦片合金发生熔化脱落。现将有关拖拉机发生烧瓦的原因及防护措施介绍给大家。
- 热效应及热弹变形对三油叶滑动轴承润滑性能的影响
- 作者：黄滨 郭嘉 陈志澜 王乐勤 来源：第四届全国水力机械及其系统学术会议 年份：2011 数据类型 ：会议论文 关键词： 三油叶滑动轴承 热弹变形 热效应
- 描述：本文针对三油叶滑动轴承，建立了不考虑润滑油热效应的HD 模型、考虑热效应的THD 模型、THD +弹性变形模型以 及TEHD 模型等四种计算模型，并将所建立的模型应用于算例分析，得到油膜压力、温度
- 水泵水轮机双向推力轴承三维热弹流动力润滑性能分析
- 作者：黄滨 吴军令 武中德 陈志澜 王乐勤 来源：青年摩擦学者与“十二五”发展——2011年全国青年摩擦学与表面工程学术会议 年份：2011 数据类型 ：会议论文 关键词： 双向推力轴承 水泵水轮机 三维热弹流
- 描述：为分析水泵水轮机双向推力轴承的动力润滑性能,建立了推力轴承的三维热弹流动力润滑数学模型,并给出了合理的边界条件。将本文所建立的计算模型应用于算例分析,得到额定工况下的油膜厚度分布、油膜压力分布和瓦块
- Analysis of Cognitive Radio Spectrum Access with Finite Primary Users and Infinite Secondary Users
- 作者：Qiming Tian Chuan Ma Guanding Yu Aiping Huang 来源：2010年无线通信与信号处理国际会议 年份：2010 数据类型 ：会议论文 关键词： 双向推力轴承 水泵水轮机 三维热弹流
- 描述：In the cognitive radio networks, the users’ spectrum access behavior determines the system capacity and spectrum utilization. There are three classical schemes for cognitive radio spectrum access: the random channel assignment, the reservation based assignment and the non-random channel assignment. In this paper, we study the performance of these schemes in a new scenario: a cognitive radio network with finite primary users and infinite secondary users. We model the users’ behavior in these schemes by Markov chains. Moreover, the blocking, transition and dropping probabilities of the secondary users based on the user connection rate are derived as the performance metrics. Furthermore, we evaluate the secondary system capacity of these schemes. Numerical results show that the random and nonrandom channel assignments can get the lowest blocking probability, the reservation based assignment can get the lowest dropping probability, and the non-random channel assignment can provide the most system capacity and avoid the channel handoff for the secondary users.
- Space-Time-Energy Based Forwarding Protocol For Underwater Acoustic Sensor Networks
- 作者：Qiming Tian Juan Wen Guanding Yu 来源：2010年通信、电路与系统国际会议 年份：2010 数据类型 ：会议论文 关键词： 双向推力轴承 水泵水轮机 三维热弹流
- 描述：The specificity of underwater acoustic channel environment brings the new challenges, such as limited energy supply, high latency and node float mobility, on the development of routing protocols for underwater acoustic sensor networks. The new features require the routing protocols with low energy consumption, real-time and self-organization. But the existing routing protocols for underwater acoustic sensor networks only aimed at one or two of the above factors. In this paper, we propose a new Space-Time-Energy based forwarding protocol, called STE protocol, by integrating the position of the nodes, propagation delay, and energy consumption. Simulation results show that the STE protocol outperforms other routing protocols in terms of the success transmission rate and energy effectiveness.
- The Study on Measurement Characteristics of Fluidic Flowmeters Sensors with CFD
- 作者：Dailiang Xie Ning Cheng Shan Tao Ting Fang Guowei Liang 来源：第八届智能控制与自动化世界大会 WCICA 2010 年份：2010 数据类型 ：会议论文 关键词： 双向推力轴承 水泵水轮机 三维热弹流
- 描述：CFD technology is employed to simulate the fluidic flowmeters. A modified structure, that with double-target and polygonal surface, is proposed. The Measurement Characteristics are compared with the other two fluidic flowmeters, named in the paper meter with single-target, meter with double-target and straight surface. The flow fields are illustrated. The performance and the relationship between the flowrate and the oscillation frequency for each meter are obtained. Some useful theoretical information can be provided for the design and optimization of fluidic flowmeters in this work.
- The Cause of Independent Innovation Dilemma and its Solutions
- 作者：ZHENG Jianzhuang JIANG Haixia 来源：The Fifth International Conference on Global Manufacturing and China 年份：2009 数据类型 ：会议论文 关键词： 双向推力轴承 水泵水轮机 三维热弹流
- 描述：After technological acquisition, processes innovation and product optimization, many enterprises often fall into secondary innovation dilemma: stick to creative imitation, try hard to make independent