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121.
现代教育技术的普及应用是促进高职院校教育教学改革、提高教学质量的重要手段,本文从现代教育技术普及应用的重要性、当前高职院校应用现代教育技术组织教学的现状以及高职院校如何普及现代教育技术应用等几个方面,阐述了自己的观点。 相似文献
122.
介绍了国际标准书号的相关知识,分析了10位及13位中国标准书号的组成结构及其校验码的生成方法,并利用Delphi实现校验码生成及不同位数中国标准书号之间相互转换的程序。 相似文献
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124.
The impact of misregistration on SRTM and DEM image differences 总被引:2,自引:0,他引:2
Thomas G. Van Niel Tim R. McVicar LingTao Li John C. Gallant QinKe Yang 《Remote sensing of environment》2008,112(5):2430-2442
Image differences between Shuttle Radar Topography Mission (SRTM) data and other Digital Elevation Models (DEMs) are often performed for either accuracy assessment or for estimating vegetation height across the landscape. It has been widely assumed that the effect of sub-pixel misregistration between the two models on resultant image differences is negligible, yet this has not previously been tested in detail. The aim of this study was to determine the impact that various levels of misregistration have on image differences between SRTM and DEMs. First, very accurate image co-registration was performed at two study sites between higher resolution DEMs and SRTM data, and then image differences (SRTM–DEM) were performed after various levels of misregistration were systematically introduced into the SRTM data. It was found that: (1) misregistration caused an erroneous and dominant correlation between elevation difference and aspect across the landscape; (2) the direction of the misregistration defined the direction of this erroneous and systematic elevation difference; (3) for sub-pixel misregistration the error due solely to misregistration was greater than, or equal to the true difference between the two models for substantial proportions of the landscape (e.g., greater than 33% of the area for a half-pixel misregistration); and (4) the strength of the erroneous relationship with aspect was enhanced by steeper terrain. Spatial comparisons of DEMs were found to be sensitive to even sub-pixel misregistration between the two models, which resulted in a strong erroneous correlation with aspect. This misregistration induced correlation with aspect is not likely specific to SRTM data only; we expect it to be a generic relationship present in any DEM image difference analysis. 相似文献
125.
Data services via wireless networks and mobile devices have experienced rapid growth worldwide. We investigated the factors influencing adoption of wireless mobile data services (WMDS) in China and tested our model for explaining adoption intentions there. We argued that individuals form their intention to adopt WMDS under the influence of wireless mobile technology, the social environment, personal innovativeness of IT, trust awareness, and the facilitating conditions. We examined the simultaneous effects of these five influences on beliefs in the context of wireless Internet data services via mobile phones. Survey data were collected from 1432 participants in several metro cities across China. The findings suggest that WMDS adoption intention in China is determined by consumers’ perceived usefulness and perceived ease of use of WMDS. Theoretical and practical implications are included in our paper. 相似文献
126.
"现代办公设备"是一门操作性、实用性和应用性极强的课程,是高职计算机专业和计算机相关专业学生必修的一门课程。如何使学生掌握现代办公设备的操作技能启发学生的创造性思维,引导学生掌握核心的操作技巧。该文根据自己近几年的教学实践经验,谈谈在该课程教学过程中的几点体会。 相似文献
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128.
罗丹 《数码设计:surface》2009,(7):230-232
近年来,国产动画产业成长迅速,日益朝着产业规模化的方向发展,然而在动画艺术的创作上却始终找不到准确的定位,无法突破瓶颈。本文试从动画电影的内容与形式两方面进行分析,探索一条适合中国动画发展的道路,提出了结合贴近现代社会生活的题材与符合中国传统审美意识的艺术形式的创作理念。 相似文献
129.
农业古籍断句标点模式研究 总被引:4,自引:0,他引:4
农业古籍的整理已经引起了众多学者和专家的注意,但是,对于农业古籍的自动断句、标点模式的研究仍付之阙如。本研究探索并总结出部分农业古籍断句、标点识别模式。首先采用句法特征词断句法、同义语标志词法进行初步断句;进而利用反义复合词、引书标志、时序、数量词、重叠字词、动名结构及比较句法进一步对子句进行断句、标点;最后使用农业用语和禁用模式表进一步提高断句、标点后农业古籍的可读性和准确性。经测试表明,断句、标点的平均准确率分别达到48%和35%,证明本方法具有一定的正确性和可行性。 相似文献
130.
A new hybrid control technique for operation of DC microgrid under islanded operating mode
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Vahid Mortezapour Sajjad Golshannavaz Edris Pouresmaeil Amin Yazdaninejadi 《电力系统保护与控制》2022,7(4):646-656
This study proposes a novel combined primary and secondary control approach for direct current microgrids, specifically in islanded mode. In primary control, this approach establishes an appropriate load power sharing between the distributed energy resources based on their rated power. Simultaneously, it considers the load voltage deviation and provides satisfactory voltage regulation in the secondary control loop. The proposed primary control is based on an efficient droop mechanism that only deploys the local variable measurements, so as to overcome the side effects caused by communication delays. In the case of secondary control, two different methods are devised. In the first, low bandwidth communication links are used to establish the minimum required data transfer between the converters. The effect of communication delay is further explored. The second method excludes any communication link and only uses local variables. Accordingly, a self-sufficient control loop is devised without any communication requirement. The proposed control notions are investigated in MATLAB/Simulink platform to highlight system performance. The results demonstrate that both proposed approaches can effectively compensate for the voltage deviation due to the primary control task. Detailed comparisons of the two methods are also provided. 相似文献