原理

The air valve is original designed according to the valve working principle.

气阀是根据阀工作原理，自行设计而成。

Base on the risk analyses on popular and fire-prone appliances such as air conditioner, refrigerator, washer, television and water heater, etc., results from research by experts world-wide together with our own experience of investigating fire accidents, this paper reviews and presents research results on causes of fire and the investigation methods. We propose several major factors which lead to most of the accidents of home appliance fire. These factors include flaws in design, failures of components, environmental conditions and improper operations.

本文的主要工作及结果如下： 1、通过对空调器、电冰箱、洗衣机、电视机和电热器具(包括电熨斗、电热毯、电热水器)等常见的、容易引起火灾的家用电器的工作原理和结构特点进行分析，指出容易引起火灾的因素，并参考国内外火灾事故调查专家和同行的研究成果，总结出家用电器火灾发生的主要原因是由于设计制造缺陷、元器件故障、外界环境影响和使用者操作不当等几大因素造成的。

Combining the principle of the equal thickness interference of air wedge with the CCD image-processing technique,a high precision automatic measurement method of thermal expansion coefficient is presented.

将空气劈尖的等厚干涉原理与CCD图像处理技术相结合，提出了一种对材料热膨胀系数进行高精度自动测量的新方法。

This article briefly introduces the operating principle of the Gas Air-Condition and both its developing history and current situation at home and abroad.

本文简单介绍了燃气空调的工作原理和其在国内外的发展历史和发展现状。

Air-conditioning chillers to do the work of energy conservation, the operator must understand the entire air-conditioning units and systems to adapt to the working principle and characteristics of the operation units.

要使风冷冷水机组的工作做到节能，操作人员要了解机组及整个空调系统的工作原理和适应机组特点的操作程序。

This article introduces the principles of the database, type, and its development prospects in the air-conditioning system applications.

本文主要介绍了有关数据库的原理、类型、发展前景及其在空调系统中的应用。

Push-pull air-cushion platform is the first non-continuously moving air-cushion vehicle that applied worming bionic principle.

推拉式气垫运载平台是第一台应用蠕动式仿生原理设计的非连续运动型气垫车，这不同于以往设计的气垫车。

Based on mechanism and vehicle theories theoretical analysis is pursued and normal driving conditions are put forward. The relations are analyzed between load distribution and power consumption. Mechanical formula is proposed. Furthermore in this paper the theoretical model of the total power consumption is established, and the relations of the total minimized power consumption with the air-cushion pressure and the fan revolution are discussed. The optimum operation point is put forward. The dynamic digital simulation studies are carried out on the operating procedure of the half-track air-cushion vehicle on soft terrain. Mechanical parameters and soil mechanics characteristics affecting vehicle power consumption and riding performance are analyzed. At the same time according to the model formula, the automation control problem is discussed. It is a theoretical instruction for further automation control.

本文还从力学和车辆原理的角度进行了理论分析，推导了半履带式气垫车的需求功率及正常行驶条件，研究了气垫压力和功率消耗之间的关系，提出了力学模型公式；建立了半履带式气垫车总功率消耗的理论模型，研究了最小功率消耗时功率与垫压及表征气垫车行驶状态的各参数的关系，分析了相应的影响因素，并提出了最佳工作状态的定义；同时进行了半履带式气垫车在软地面的行驶过程的动态数字仿真试验研究工作，对影响车辆功率消耗和行驶平顺性的各力学参数和土壤参数进行了分析，得到了各运行状态参数的变化规律，验证了最佳工作状态和最佳垫压的理论，根据力学模型公式对进一步的自动控制问题进行了探讨，为系统的控制提供了理论指导。

So in this paper based on the characteristics and the optimum state theory of the vehicle, some kinds of control schemes are compared and discussed, and the fuzzy PID control scheme is adopted at last. The relation between air-cushion pressure and fan rotational speed on the optimum driving state is studied. The cushion pressure is used as controlled variable and the fan revolution is used as regulated variable. And transducer and fan motor are actuators.Based on the structure and operating properties of half-tracked air-cushion vehicle, the control system scheme and structure are presented. A control scheme using the self-tuning PID fuzzy logical controller is adopted. Fuzzy rules are set up and some researches have been done for fuzzy tuning method. At the same time the real-time measurement scheme by computer control is proposed, and electric circuits are designed. In the control system of half-tracked air-cushion vehicle cushion pressure P〓 is used as controlled variable and the fan speed n〓 as regulated variable.

因此本文以半履带式气垫车的特性和最佳工作状态理论为指导，通过对各种控制方法的比较与探讨，提出采用模糊PID控制方案，并且研究了在最佳工作状态下垫压及风机转速的关系，提出气垫压力作为控制参数，变频器和风机电机为执行机构，风机转速为调节量；主要进行了自整定模糊PID控制器的设计，研究了自整定PID模糊控制器的实现方法，编制了模糊控制规则，制定了模糊控制参数查询表，并分析了影响自整定模糊控制器相关的影响因素，确定了模糊控制表；为了实现半履带式气垫车的自动控制，还提出了计算机模糊控制系统的原理与结构，设计了相应的测量电路与控制软件。

According the character of s7-200 PLC ,we introduce the principle of controlling and the designing way of hardware and software in air-pressure controlling .the built-system run well ,operate simply and is applied.

根据S7-200可编程序控制器的特点，详细介绍其在控制风压中运用的控制原理，软件及硬件的实现方法。设计完成的系统运行可靠、操作方便、具有很强的实用性。

I can not make it blossom and suits me

我不能让树为我开花

When temperatures are above approximately 80 °C discolouration of the raceways or rolling elements is a frequent feature.

当温度高于 80 °C 左右时，滚道或滚动元件褪色是很常见的特征。