地图数字化误差分析及探讨     

刘珊红  于海龙  赵吉先 《测绘与空间地理信息》2001,24(3):16-18

文章分析了地图数字化误差的分类和主要来源,在目前研究现状的基础上,引入了分形分维理论,作者主要研究了分形分维理论在地图数字化误差分析中的应用 ,并通过实验分析,得到一定的结论.  相似文献   

南斯拉夫地籍图的发展     

Gosto.  M 赵吉先 《华东地质学院学报》1993,16(3):212-214,220

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利用最大熵和几何条件进行兴趣点匹配     

Jiang.  Z 赵吉先 《华东地质学院学报》1993,16(3):235-240

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面向21世纪的测量工程专业教学改革的构想     

赵吉先 《地理信息世界》1998,(1)

本文探讨了21世纪对人才的要求和测量工程专业面临的挑战,讨论了面向21世纪的测量工程专业教学改革和重组课程体系的构想。  相似文献   

A New Method of Significance Testing for Correlation-Coefficient Fields and Its Application     

Xiaojuan SUN  Siyan LI  Julian XL WANG  Panxing WANG  Dong GUO 《大气科学进展》2022,39(3):529-535

Correlation-coefficient fields are widely used in short-term climate prediction research. The most frequently used significance test method for the correlation-coefficient field was proposed by Livezey, in which the number of significantcorrelation lattice(station) points on the correlation coherence map is used as the statistic. However, the method is based on two assumptions:(1) the spatial distribution of the lattice(station) points is uniform;and(2) there is no correlation between the physical quantities in the correlation-coefficient field. However, in reality, the above two assumptions are not valid.Therefore, we designed a more reasonable method for significance testing of the correlation-coefficient field. Specifically, a new statistic, the significant-correlation area, is introduced to eliminate the inhomogeneity of the grid(station)-point distribution, and an empirical Monte Carlo method is employed to eliminate the spatial correlation of the matrix.Subsequently, the new significance test was used for simultaneous correlation-coefficient fields between intensities of the atmospheric activity center in the Northern Hemisphere and temperature/precipitation in China. The results show that the new method is more reasonable than the Livezey method.  相似文献   

试论温度对反应堆施工测量的影响     

赵吉先 《测绘通报》1999,(2):24-26

本文从工程力学、热学、测量学入手,探讨了温度对反应堆施工测量中的垂直度和内部微型控制网水平长度的影响,得出一些有益结论。  相似文献   

空间直角坐标系非线性坐标转换     

周兴华  赵吉先  鲁铁定 《北京测绘》2005,(1):33-35

本文通过线性坐标转换在转换参数较大时产生的弊端从而引出了非线性坐标转换模型,并且从公式的推导中可得到非线性转换中顾及了二次项及交叉项的直接解法以及转换参数的计算方法。最后通过算例证明了在参数较大时线性坐标转换中存在较大误差,同时说明了非线性坐标转换模型的有效性和实用性。  相似文献   

Antibiotic resistance of bacteria isolated from shrimp hatcheries and cultural ponds on Donghai Island, China   总被引：1，自引：0，他引：1  

Zhang YB  Li Y  Sun XL 《Marine pollution bulletin》2011,62(11):2299-2307

The resistance of bacteria to 12 different antibiotics was investigated in shrimp farms on Donghai Island, China. Antibiotic-resistant bacteria were found to be widespread in shrimp farms, indicating a high environmental risk. Further, significant differences were found in bacterial strains among farms (ANOVA, p < 0.05), showing resistance to antibiotics such as ampicillin, trimethoprim, compound sinomi, tetracycline, chloramphenicol and cefazolin. No significant differences in antibiotic resistance were found among 6 hatcheries evaluated in this study (ANOVA, p > 0.05), between exalted and traditional shrimp ponds (ANOVA, p > 0.05), and between cultural ponds and corresponding control water source sites (T-test, p > 0.05). In cultural ponds, no significant difference in bacterial resistance to antibiotics was found between water and sediment (T-test, p > 0.05), and antibiotic resistance of bacteria from water showed a significant positive correlation with that from sediment (p < 0.05). Therefore, our study indicates that bacterial multiple antibiotic resistance (MAR) is more widespread in shrimp hatcheries than ponds.  相似文献   

论《工程测量学》课程的实践教学改革简     

吴杰  赵吉先等 《测绘科学》2013,(6):204-206

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电磁波测距三角高程代替跨河水准测量的试验和分析     

赵吉先  郑万星 《华东地质学院学报》1995,18(1):82-89

本文介绍了跨河测距三角高程的试验方案，并从理论和试验两个方面讨论了测距三角高程代替跨河水准测量，得出了一些有参考价值的结论。  相似文献