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51.
SUN Zheng YU Dao-yin 《光电子快报》2006,2(1):68-71
Since actual cardiac and arterial motion is non-rigidand non-uniformbothin space andinti me[1],the quan-tification of dynamic 3-Dcurves with 2-D projections isinaccurate and sensitive to view angles . Ruan[2]andPuentes[3]reconstructed 3-D arterial centerl… 相似文献
52.
FENG Peng PAN Ying-jun WEI Biao JIN Wei MI De-ling 《光电子快报》2006,2(3):229-232
Recently,there has been a growing awareness to theobservation that wavelets may not be the best choiceforrepresenting natural i mages .This observation is due tothe fact that wavelets are blindtothe smoothness alongthe edges commonly found in i mages .In … 相似文献
53.
随着卫星重力测量技术的不断完善和发展,使得利用重力场模型进行GPS点高程转换的精度和可靠性都获得了极大提升。文章利用SRTM、DTM2006.0模型和EGM2008模型求得阳山矿区GPS点剩余高程异常,并进行残余高程异常拟合,建立阳山矿区剩余高程异常转换计算方法。在对阳山矿区22个D级GPS点,48个E级GPS点的高程数据进行比较后,发现此方法转换最高精度能达到2.8 cm,最差精度为4.4cm,平均精度为3.2 cm,从而证明了此方法可以提高阳山矿区GPS高程转换的精度。 相似文献
54.
叙述了利用EPS2008生成宗地图的方法,通过比对不同软件输出的宗地图,指出利用EPS2008软件自动输出宗地图,不仅可以提高宗地图的制作效率,而且还能保持数据的高度统一。 相似文献
55.
To overcome the problem that soft sensor models cannot be updated with the process changes, a soft sensor modeling algorithm based on hybrid fuzzy c-means (FCM) algorithm and incremental support vector machines (ISVM) is proposed. This hybrid algorithm FCMISVM includes three parts: samples clustering based on FCM algorithm, learning algorithm based on ISVM, and heuristic sample displacement method. In the training process, the training samples are first clustered by the FCM algorithm, and then by training each clustering with the SVM algorithm, a sub-model is built to each clustering. In the predicting process, when an incremental sample that represents new operation information is introduced in the model, the fuzzy membership function of the sample to each clustering is first computed by the FCM algorithm. Then, a corresponding SVM sub-model of the clustering with the largest fuzzy membership function is used to predict and perform incremental learning so the model can be updated on-line. An old sample chosen by heuristic sample displacement method is then discarded from the sub-model to control the size of the working set. The proposed method is applied to predict the p-xylene (PX) purity in the adsorption separation process. Simulation results indicate that the proposed method actually increases the model’s adaptive abilities to various operation conditions and improves its generalization capability. 相似文献
56.
57.
An evaluation of resident exposure to respirable particulate matter and health economic loss in Beijing during Beijing 2008 Olympic Games 总被引:1,自引:0,他引:1
Previous epidemiological studies showed that air pollutants, especially respirable particulate matter, including PM10, could impose harmful effects on human health. The assessment of the effects of PM10 on mortality and morbidity makes an important basis for enhancing pollution control efforts, and for protecting public health. In this study, we measured the levels of Beijing residents' exposure to PM10 during three different time periods around the Beijing Olympic Games held in 2008, and calculated the economic cost associated with human health. A comparative analysis of human exposure to PM10 and associated health economics was also made to see the difference between 2005 and 2008. GIS technology was employed to interpolate the distribution of population and PM10 data collected by 27 stations at a scale of 1 km × 1 km. Study results show that Beijing's population is distributed in a highly inhomogeneous manner, with the majority of people dwelling in the city proper. During the Olympic Games, population-weighted PM10 exposure came down by 46% and 19% respectively, compared with the pre-OG and the post-OG periods. Consequently, the economic cost associated with human health during the Games came down by 38% and 16% respectively, compared with the pre-OG and the post-OG periods. Comparative analysis shows that during the Olympic Games, both PM10 and the economic cost associated with health as a proportion of GDP sat at the bottom of the 4-year statistics, indicating that in addition to favorable weather conditions, enhanced traffic and emission control policies and measures have produced a noticeable effect on PM10 reduction. 相似文献
58.
No authorship indicated 《Canadian Metallurgical Quarterly》2009,64(5):474
Presents a list of the American Psychological Association's grant and contract activity in 2008. Titles, sponsors/grants, and total award amounts are provided. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
59.
Fuller-Rowell Thomas E.; Burrow Anthony L.; Ong Anthony D. 《Canadian Metallurgical Quarterly》2011,47(6):1608
The current study considered the influence of the 2008 presidential election on the racial identity of African American college students (Mage = 19.3 years; 26.3% male). The design of the study consisted of 2 components: longitudinal and daily. The longitudinal component assessed 3 dimensions of racial identity (centrality, private regard, and public regard) 2 weeks before and 5 months after the election, and the daily diary component assessed racial identity and identity exploration on the days immediately before and after the election. Daily items measuring identity exploration focused on how much individuals thought about issues relating to their race. Analyses considered the immediate effects of the election on identity exploration and the extent to which changes in exploration were shaped by racial identity measured prior to the election. We also considered immediate and longer term changes in racial identity following the election and the extent to which longer term changes were conditioned by identity exploration. Findings suggest that the election served as an “encounter” experience (Cross, 1991, 1995, pp. 60–61), which led to increases in identity exploration. Moreover, analyses confirmed that changes in identity exploration were most pronounced among those with higher levels of racial centrality. Results also suggest that the election had both an immediate and a longer term influence on racial identity, which in some instances was conditioned by identity exploration. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
60.
Demo测试软件是基于Visual Studio 2008工具开发出的一个单文档界面程序。其主要的功能是生成一个将要在高速公路显示屏上显示的信息播放列表文件,该播放列表文件中要包含播放屏数、每屏停留时间、屏幕上显示字体的方式、速度、在屏幕上显示初始字体的位置、字体的大小、颜色以及字体间距,该功能通过“添加”、“删除”、“发送”、“列表”、“保存”5个按钮实现。 相似文献