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Land Cover Classification Based on MODIS Data in Area to the North-west of Beijing
基于MODIS数据的北京西北部地区土地覆盖分类研究

LIU Aixia,WANG Jing,LV Chunyan,<br>刘爱,王静,
地理科学进展 , 2006,
Abstract: This paper presented the research on land cover classification in area to the northwest of Beijing based on MODIS 16-day NDVI and 8-day LST time series datasets in 2002, 1: 50000 DEM and some ancillary data. We first selected a land use/land cover classification system suitable to MODIS remote sensing data, the classification system was built based on remote sensing data after comparing and summarizing the features of different remote sensing data. Secondly, in order to improve the classification accuracy, we performed a PCA transform on the MODIS NDVI time series data to remove noises, and selected the first four components as the basic land cover classification data. Finally, combined with MODIS LST data, DEM and other ancillary data of study area, we applied fuzzy K-means non-supervised classifier to get the land cover automatic classification in area to the north-west of Beijing. After post-classification process of the original classification result, the last land cover classification map of area to the north-west of Beijing in 2002 was got. Compared with the manual interpretation classification result based on the ETM remote sensing data, we had a classification accuracy evaluation about MODIS data. The final classification result showed that the 250m MODIS NDVI time series data and the classification method used in the paper not only can suit to large-scale land cover classification, but also can have better classification accuracy. Based on the classification result of area to the north-west of Beijing, we had a statistic about the area of seven land cover types and analyzed their geographic distribution.
Insect community structure in spring and summer cotton fields
不同类型棉田昆虫群落结构研究

LU Wen-Yan,QIN Xue-Feng,XU Yan-Ling,SHEN Zong-Xia,<br>文彦,秦雪峰,,沈宗
中国生态农业学报 , 2009,
Abstract: Community dynamics of major insect in spring and summer cotton fields were investigated according to the theory and method of community ecology from June 26 to August 20, 2007. The community structure dynamics was analyzed based on collected data on relative richness, dominance index, dominant concentration index, diversity index and evenness. The results show a rich constitution of insect communities in spring and summer cotton fields. About 48 insect species, belonging to 35 families and 10 orders are observed. In spring cotton field, the insect community comprises 39 species, 30 families and 9 orders while in summer cotton field, the insect community comprises of 43 species, 30 families and 10 orders. The dominant species are Aphis gossypii, Bemisia tabaci and Tetranychus cinnarinus. The dominant species in spring cotton field is T. cinnarinus from the end of June to the beginning of July, reaching the peak at the beginning July. The dominant species after mid. July is A. gossypii, and B. tabaci from the end of July to mid. August in the two cotton fields. Total individual numbers of insect community vary greatly. The total individual numbers of insect community and pest sub-community in spring cotton fields are always higher than in summer cotton fields. Relative richness of pests in spring cotton fields and that of the natural predator in summer cotton fields are larger. Similarity coefficient of parasitical natural predator is highest (0.949 4) and that of phytophagous pest community is lowest (0.439 4). The highest diversity indices of insect community in spring cotton fields and summer cotton fields are 1.895 3 and 2.095 1 respectively. Changes of diversity and evenness are similar in both cotton fields. However, change in aggregation index of dominance is contrary to that of diversity and evenness, which increases with decline in diversity and evenness.
Characteristics of granules in a highly efficient particulate biofilms reactor treating domestic wastewater at ambient temperature
常温处理生活污水微氧高效颗粒污泥反应器内颗粒污泥性能研究

DONG Chunjuan,LIU Xiao,CHEN Suyun,WANG Yanxia,L&#,Bingnan,<br>董春娟,刘晓,陈素云,,炳南
环境科学学报 , 2009,
Abstract: 为了分析微氧高效颗粒污泥反应器(EGSB反应器)在环境温度下处理实际生活污水时高效稳定运行的可行性,对15~26℃常温处理实际生活污水微氧EGSB反应器内颗粒污泥活性、沉淀性能、粒径分配、形态等进行研究.结果表明,15~26℃常温处理实际生活污水微氧EGSB反应器稳定运行时颗粒污泥沉速在11~79m·h-1之间,低沉速污泥有少量上浮至三相分离器底部甚至三相分离器上部,但没有出现污泥的流失,污泥浓度达到28g·L-1(以MLSS计),可获得93.4%、83.8%、74.7%和44.0%的高COD、NH+4-N、TN和TP去除率;污泥产甲烷活性并没有降低,甚至比单纯厌氧时还有所偏高;颗粒污泥的平均粒径增大,主要集中0.63~2.00mm之间,质量分数达到了89%,既能保证反应器内的高污泥浓度,又能保证污染物质向颗粒表面和颗粒内部的高效传质,提高污染物质的转化率.颗粒污泥不同层面上微生物菌群发生了很大变化,外层丝状菌占优势,内层杆菌、丝状菌、球菌混生.微生物菌群排列紧密,细胞间紧密结合,集群协同作用使代谢物质能够以最短距离高效传递,保证了微氧EGSB反应器在常温、低浓度下的高效稳定运行.
Trust Evaluation and Control Analysis of FANP-based User Behavior in Cloud Computing Environment
云计算环境下基于FANP的用户行为的可信评估与控制分析

LV Yan-xia,TIAN Li-qin,SUN Shan-shan,<br>,田立勤,孙珊珊
计算机科学 , 2013,
Abstract: The open environment in cloud computing is much more complex and unpredictable, and can not fully adapt to the new application of computer network such as cloud computing. Combining such security measures of dynamic user behavior trust, effectively confirming the untrusted cloud terminal users and correctly analyzing their abnormal behavior are the basis to ensure cloud security in complex and dynamic environment This paper adopted the method of fuzzy analytic network process(FANP) based on triangular fuzzy numbers, which can reflect the fuzziness of expert evaluation through using fuzzy numbers, and weaken the subjectivity of simply using ANP. The paper also gave a quantization calculation to the weight of each attribute in order to make the evaluation results more objective. The evaluation results provide a quantitative analysis foundation for security control based on dynamic trust and provide the quantitative basis for service providers who adopt a more safe strategy in response to a user's requesting.
基于MODIS数据的北京西北部地区土地覆盖分类研究
刘爱,王静,
地理科学进展 , 2006, DOI: 10.11820/dlkxjz.2006.02.011
Abstract: 本文主要基于MODIS16天合成的NDVI时间序列数据、8天合成LST数据、1∶5万DEM数据以及其他辅助数据相结合,进行北京西北部地区土地覆盖分类的研究。首先选取适合于MODIS数据分类的土地覆盖分类系统,然后用PCA方法对NDVI时间序列数据进行信息增强与压缩处理,以排除各种干扰因素,提高分类精度。最后结合LST数据、DEM数据及降雨温度数据,利用?齂-均值非监督分类法,进行研究区的土地覆盖分类,经过分类后处理,得到北京西北部地区的土地覆盖分类图。分类结果表明,使用250m分辨率MODIS数据,结合本文所用方法,能够实现较大区域的土地覆盖分类,并且能达到较高的分类精度。
秦岭山区野生猕猴桃资源遗传多样性分析
,王 飞?,俊辉?
西北农林科技大学学报(自然科学版) , 2009,
Abstract: [目的]利用有效的分子标记技术,对秦岭山区野生猕猴桃的遗传多样性及系统进化关系进行研究,为猕猴桃新种质的挖掘和品种遗传改良奠定基础.[方法]利用随机扩增多态性dna标记(rapd)技术,对采自秦岭山区的野生猕猴桃24个优良单株和中华猕猴桃等6个种或变种及其品种的22份资源进行了遗传多样性和亲缘关系分析.[结果]通过引物筛选,用16个rapd引物对46份猕猴桃资源扩增出235条带,其中227条为多态性条带,多态性位点比例为96.29%;各猕猴桃资源间的遗传距离为0.13953~0.80734;upgma聚类分析结果显示,'野生99-13'与'武植2号'、'魁蜜'、'金阳1号'、'武植6号'、'中华♂'和'广西红肉'等中华系列猕猴桃(a.chinensisplanch.)聚在一起,其余23份野生猕猴桃与'哑特'、'秦美'、'徐冠'、'徐香'等猕猴桃品种遗传距离较近.[结论]24份秦岭野生猕猴桃资源中,'野生99-13'属中华系列猕猴桃,其余23份均属于美味猕猴桃(a.deliciosavar.deliciosa).
云计算环境下基于fanp的用户行为的可信评估与控制分析
,田立勤,孙珊珊?
计算机科学 , 2013,
Abstract: 云计算环境下,开放的运行环境使其面临重大的安全挑战,仅仅提供用户身份认证的安全控制已经不能完全适应云计算等新型计算机网络的应用。结合动态的行为可信的安全措施,有效地确定不可信云终端用户并正确分析云用户的异常行为是在复杂动态环境下保证云安全的基础。采用基于三角模糊数的模糊网络分析法(fanp),通过使用模糊数来反映专家评判的模糊性,弱化了单纯使用anp方法存在的主观性,并对网络用户行为各属性的权重进行了量化计算,使评判结果更加客观。评价结果为基于动态信任的安全控制提供了量化分析的基础,为服务提供者采取更加安全的策略来响应用户请求提供了量化依据。
应用盐溶蛋白电泳法对绒泡菌目黏菌的鉴定
王晓丽,,,李玉
吉林农业大学学报 , 2007,
Abstract: ?对煤绒菌等4种绒泡菌目黏菌显型原质团进行了盐溶蛋白的电泳分析。结果表明:煤绒菌、圈绒泡菌的特征峰分别为4个,针箍菌特征峰5个,扁绒泡菌特征峰2个。特征谱带重复性强,可以作为在原质团水平上鉴定黏菌种类的一种方法。
Contents of organic matter and major nutrients and the ecological effect related to land application of sewage sludge in China
中国城市污泥有机质及养分含量与土地利用

LI Yan Xia,<br>李
生态学报 , 2003,
Abstract: Land application is an important way for treatment of municipal sewage sludge both in China and in the world. Therefore, the contents of organic matter and nutrients in sewage sludges and their effect on promotion of plant growth have been highlighted when they are recycled in lands. There have been some systematic summaries for land application of sewage sludges in developed countries while those have not been reviewed in China though there are some specific research related to their contents of organic matter and major nutrients. Related documents about land application of sewage sludges are summarized in the paper, which focuses on the organic matter and nutrients in sewage sludges and their effects on land application. It shows from the statistical analysis of the contents of organic matter and nutrients in China's municipal sewage sludges from 29 wastewater plants that the average contents of organic matter, total N, total P and total K are 385, 27, 14 3 and 7g/kg, respectively, which are 1/3~2/3 higher than their responding contents in pig manure, respectively. It is found that the average contents of organic matter in the sewage sludges have being increased recently in China. Many supported that the sewage sludges can be applied to agriculture, forestry and horticulture because they benefit soil fertility and plant growth. It is also indicated that the contents of heavy metals have being decreased, since the last two decades. which is beneficial for land application of sewage sludges, However, the studies on harmfulness of organic pollutants and pathogens resulting from land application of sewage sludges are still limited and long term effects of their land application are needed to be understood through long term experiments in China.
CONVERGENCE ANALYSIS OF THE SIGN ALGORITHM WITH $\phi$-MIXING INPUT
符号算法在$\phi$-混和输入情况下的收敛性

Yan Xia ZHANG,<br>张
系统科学与数学 , 2004,
Abstract: Based on result of E. Eweda(2000), this paper has considered the problem of adaptive plant identification using sign algorithm (SA). Asymptotic time-averaged convergence for the mean absolute weight misalignment was proved for sufficient small step size and any initial weight vector, with the input and noise sequences being mixing.
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