Theoretical and Empirical Analysis on Influence Factors of Modern Agricultural Equipment Level in the Process of Agricultural Sustainable Development

Abstract

To promote modern agricultural equipment level is one characteristic of constructing and developing modern agriculture in China. This paper makes up stepwise linear regression analysis model of influence factors of modern agricultural equipment level, and chooses rural labor, per capita income of rural residents, rural investment, proportion of people at secondary education level and at higher level in per hundred rural labor force and arable land area as independent variables, and total power of machine as induced variable. The major results show that the relativity of modern agricultural equipment level, rural investment and education level of peasants is remarkable, and they are the major influence factors of modern agricultural equipment level. Raising investment level of rural infrastructure construction as well as and research and development and promotion of advanced and applicable modern agricultural equipment, improving quality and education level of peasants can accelerate the development of China’s modern agricultural equipment effectively in the process of agricultural sustainable development.     

基于模糊层次分析法的组织因素影响度识别

基于模糊层次分析理论,构建影响系统安全的组织因素模型,确定影响系统安全的组织因素指标体系,利用因素相对影响度R、因素总体影响度C和因素重要度I来表征组织因素对系统安全的影响程度。采用该因素影响度方法分析了组织因素对某核电站系统安全的影响,发现监督、安全文化培训、领导对安全的态度、程序的完备性、部门间的交流与反馈、协调、个人的意识和态度、岗前技能培训、部门内的交流与反馈是对核电站运行安全影响最大的组织因素。     

高速铁路列车运行冲突管理研究现状综述

在定义高速铁路列车运行冲突的基础上,分析列车运行冲突的产生机理,从4个不同角度对列车运行冲突进行分类。归纳并分析列车运行冲突管理的研究历程及国内外对列车运行冲突管理问题研究的现状。分析表明,国内外对列车运行管理的研究主要是依托列车运行图优化和调度指挥系统开发而进行的,对列车运行冲突管理的专门和系统研究尚缺,没有适合我国国情和路情的高速铁路列车运行冲突管理体系。指出冲突分析、冲突化解和基于冲突管理的列车运行调整方法及运行图优化技术等问题是我国高速铁路冲突管理的主要内涵,将时变性、冲突可蔓延性、分割管理和复杂性等归结为高速铁路冲突管理的特点。     

基于中日比较的人口城市化对耕地影响机制研究

人口城市化是对耕地变动产生复合影响的一个过程.人口由农村向城市的转移是城市土地扩张的基本动力;这对耕地形成了占用的直接影响,我国人口城市比对耕地减少的直接影响度约在5%～10%之间.人口城市化对耕地的间接影响通过城市人均用地比农村少,土地利用集约度高,可以间接减少耕地占用;同时农村人口的减少,可以推动村镇合并,整理土地,增加耕地等途径来实现.因此,人口城市化对耕地存在积极的间接影响.人口城市化过程对耕地变动的复合影响结果是积极的还是消极的,将取决于一是城市化发展状态,即与工业化发展是否同步;二是村镇合并集中是否及时到位.为此,文章对中日人口城市化对耕地影响机制进行了比较.     

烟气流量对除尘效率测定的影响

除尘效率是衡量废气污染原治理设备性能的重要指标。因现场监测条件的制约，会出现除尘系统进出口烟气流量差距过大的现象，由此不能真实反映除尘系统的状况。本文通过对实测数据的分析说明：对高效率除尘器而言，进出口烟气流量相关1-1.5倍时，对除尘效率的计算可视为无影响。     

东西方文化分别对汉、英语语言的影响

文化是一个社会全部物质文明和精神文明的总和，是具有较强民族性的东西。一方面，语言既是文化的一部分，又是文化的载体；另一方面，文化对语言的发展又起着重要的制约作用。东西方文化在哲学观念、历史背景、生活环境、生活习俗等方面的不同分别影响着汉语和英语的形成、发展及应用，并使得它们在长期的使用中逐渐形成自己的特色。     

Influence of ignition position and obstacles on explosion development in methane–air mixture in closed vessels

The paper outlines an experimental study of influence of the ignition position and obstacles on explosion development in premixed methane–air mixtures in an elongated explosion vessel. As the explosion vessel, 1325 mm length tube with 128.5 mm diameter was used. Location of the ignition was changeable, i.e., fitted in the centre or at one of ends of the tube, when the tube was in a horizontal position. When it was in a vertical position, three locations of the ignition (bottom, centre and top) were used. In the performed study, the influence of obstacles on the course of pressure was investigated. Two identical steel grids were used as the obstacles. They were placed 405 mm from either end of the tube. Their blockage ratio (grid area to tube cross-section area) was determined as 0.33 for most of experiments. A few additional experiments (with smaller blockage ratio—0.16) were also conducted in order to compare the influence of the blockage ratio on the explosion development. Also some experiments were conducted in a semi-cylindrical vessel with volume close to 40 l.

All the experiments were performed under stabilized conditions, with the temperature and pressure inside the vessel settled to room values and controlled by means of electronic devices. The pressure–time profiles from two transducers placed in the centreline of the inner wall of the explosion vessel were obtained for stoichiometric (9.5%), lean (7%) and rich (12%) methane–air mixture. The results obtained in the study, including maximum pressures and pressure–time profiles, illustrate a quite distinct influence of the above listed factors upon the explosion characteristics. The effect of ignition position, obstacles location and their BR parameters is discussed.

The additional aim of the performed experiments was to find the data necessary to validate a new computer code, developed to calculate an explosion hazard in industrial installations.     

Physical and Economic Sustainability of Water: New Approach Using the Case of the Big Lost River,Idaho

A new approach for evaluating water sustainability is introduced by comparing physical and economic sustainability. To achieve physical sustainability, water should be available in sufficient quantity and of good quality and used efficiently. The economic sustainability can be achieved by balancing between costs and values of water. The objectives of this study were to estimate the physical and economic sustainability of surface water in the Big Lost River, south–central Idaho. The study used a Bayesian network by building a graphical diagram of nodes representing all significant variables related with the sustainability, such as water demand, water quality, and the different costs and values of water. The study showed that the likelihood of the physical sustainability is less than that of the economic sustainability, which is attributed to the scarcity of water in the Big Lost River. Readers should send their comments on this paper to: BhaskarNath@aol.com within 3 months of publication of this issue.     

基于贝叶斯网络的人因可靠性评价

提出一种贝叶斯网络的人因可靠性评价(HRABN)方法,其中的每个因子对应于贝叶斯网络中的节点,该方法可对人因可靠性作定量分析和定性分析。在定性分析上,节点的因果关系(HRA中的因子关系)及需要改进的薄弱节点都直观地显示在层次图中;在定量分析方面,对节点因子后验概率的推断通过HRA中的先验信息(包含仿真数据、现场操作及专家知识等)和最新信息得到。如果人因可靠性贝叶斯网络中的每个节点的先验概率分布和后验概率分布都已知,模型的可信性就可通过贝叶斯因子进行定量验证。贝叶斯网络扩展性好,当有新的节点因子需要考虑时,只需要补充对应的节点;笔者的方法也能很好地应用在不同行业的HRA。     

气象和环境对装备的影响及适应性对策

气象条件、环境条件对飞机空中飞行作战有着至关重要的影响。为了提高新时期我军的战斗力,就必须做好新型武器装备的防护,制定出切实有效的防护措施,有效发挥我军新型战机作战效能。