Automatic measurement of two dimensional object

Some core techniques related with automatic measurement of two dimensional object are discussed. Two kinds of corner point detecting methods are given. Least square fitting is used for edge line fitting. Region selection for accurate measurement is proposed. Combined with image recognition, location and macro recording file, automatic measurement of two dimensional object is realized. Supported by National Key Science and Technology Research Project During the 9th Five-year Peroid Sun Xiaoan: born in 1968. Associate professor, Ph.D     

模型化方法的哲学思考

模型化方法是与实验和理论相区别的另一种重要方法。本文探讨了模型化方法产生的背景和内涵，指出模型化方法是历史发展的必然，是进行科学技术研究的重要方法。计算机的高速发展带来了模型化方法的美好前景，但模型化方法本身具有一宣扬局限性，同时也面临着一些问题。     

一种基于改进自适应卡尔曼滤波的GNSS/INS组合导航算法

在全球卫星导航系统/惯性导航系统(global navigation satellite system/inertial navigation system,GNSS/INS)组合系统中,状态模型误差和异常扰动的影响严重降低了标准卡尔曼滤波的性能,而基于预测残差自适应的卡尔曼滤波随计算次数的增加滤波效果降低,且使用统一的自适应因子调节不可靠。针对上述问题,提出一种改进算法,利用预测残差建立的统计量调节位置向量和速度向量,避免了其他参数对滤波的平衡作用;通过预测残差的概率密度建立马氏距离进行假设检验,在模型正常时使用标准卡尔曼滤波,模型异常时使用改进滤波算法;采用实测车载数据对标准卡尔曼滤波、单因子自适应滤波和本文的滤波方法进行评估,实验结果表明:改进的自适应卡尔曼滤波的滤波算法效果良好,证明了所提算法的有效性。     

一种基于模糊化决策树的分类算法

提出了一种基于模糊化决策树的自适应分类算法.介绍基于决策树的分类算法,指出训练样本分布不均匀或树剪枝操作都可能引起分类规则的不完全,导致分类出现"盲区".引入决策树的模糊化方法及分支(规则)激活度的概念,给出一种新的自适应分类算法.并用实例分析表明,该算法不仅解决了分类规则不完全的问题,而且也提高了决策树分类的精度及分类结果的可解释性.     

对以高锰酸钾为氧化剂的饮用水工艺流程的细胞毒性评价

用2项细胞生物学指标--细胞增殖活性和细胞凋亡率比较了一个饮用水工艺流程各阶段有机提取物作用于细胞的毒性.实验数据表明:经强氧化剂高锰酸钾处理水后产生的有机提取物,对细胞毒性较大,但经系列水工艺处理后(机加池→煤滤→炭滤→出厂→管网),加氯出厂水和管网水的水质转好,说明该饮用水工艺流程有效地去除了对细胞具有毒性的一些污染物质.     

Construction of a multidimensional plane network-on-chip architecture based on the hypercube structure

In current network-on-chip (NOC) studies and in practical applications, the mesh structure is the most widely used and deeply researched structure. However, the hypercube structure is more symmetrical and regular than the mesh or torus structures. This paper compares the network characteristics of these three direct topologies and proposes a method to compress the hypercube into a plane structure. This structure, which has the multidimensional property based on the hypercube, is called the multidimensional plane (MDP) NOC. The compression process is divided into two steps: the transformation of router denotations and the connection of channels. Then, SystemC is used to implement the MDP NOC and it is compared with the mesh and torus NOCs in terms of four aspects of performance, including average latency time, normalization throughput, energy consumption and area cost.     

Geochemical environmental changes and dinosaur extinction during the Cretaceous-Paleogene (K/T) transition in the Nanxiong Basin, South China: Evidence from dinosaur eggshells

The complex patterns of trace elements including Ir and isotope distributions in the three K/T sections of the Nanxiong Basin prove the existence of two environmental events in the latest Cretaceous and earliest Paleocene. The first geochemical environmental event occurred at about 2 Ma prior to the K/T boundary interval, where the dinosaur diversity was hardly reduced, except that a number of pathological eggshells appeared. The second one was larger and occurred just at and near the Cretaceous-Paleogene (K/T) boundary. The extinction of the dinosaurs spread out within 250 ka with major extinction beginning at the boundary interval. This is even later than their extinction in Montana, North America and in India. The cause of the dinosaur extinction may be the result of a complex multiple events brought about by the coincidence of global environment change marked by multiple Ir and δ¹⁸O anomalies, and environmental poisoning characterized by other trace elements derived from the local source. Successive short- and long-term conditions of geochemically induced environmental stress negatively affected the reproductive process and thus contributed to the extinction of the dinosaurs. Supported by National Natural Science Foundation of China (Grant No. 40472018) and the Chinese Academy of Sciences (Grant No. 21039751)     

基于优势流效应的填埋场渗沥液回灌过程预测

渗滤液回灌对于补充垃圾堆体水分及加速降解稳定化具有重要的促进作用,垃圾堆体的非均质性和大孔隙特征造成了渗沥液流动过程出现显著的优势流效应.以双渗透率模型为基础,开展典型回灌工艺条件下垃圾堆体中渗沥液的分布规律预测研究.预测结果表明:一定限度内增大回灌速率、回灌频率、回灌量、初始含水量等因素可提高渗滤液的影响深度、入渗量和贮水率;优势流模型较传统的单域模型,区分了具有高导水性的裂隙域和高持水性的基质域,渗滤液可以更快地通过裂隙入渗、流动和排出,更符合垃圾堆体内水分多域流动行为模式;裂隙域和基质域的水分质量交换项是动态平衡的,随深度而减小.     

大米酒酒曲中优势菌群的探究

对大米酒酒曲中的微生物菌群进行分离、纯化,得到7株细菌,4株酵母菌,以及10株霉菌.该项研究为优化酒曲质量,改善酒质,提高大米酒营养价值,开发大米酒系列新品种提供参考.     

绿色建筑节水项目全生命周期综合效益经济模型

通过对影响绿色建筑节水项目全生命周期过程综合效益的构成要素的分析,采用净现值作为综合效益的评价和衡量指标,构建了含节水直接效益、环境社会效益和全生命周期增量成本在内的综合效益经济模型,并在西部某绿色建筑住宅小区节水示范项目中进行模拟应用,验证了该模型的合理性和实用性.模拟结果表明,该项目全生命周期综合效益为3 929万元,全生命周期增量成本为933万元,效费比为4.2∶1,节水项目全生命周期综合效益显著.