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1.
用VC++6.0开发Windows XP环境下串行通信程序的方法   总被引:2,自引:1,他引:2  
提出了用通信ActiveX控件来开发WindowsXP环境下串行通信程序的方案,详细讨论了通信程序设计的方法和步骤,最后介绍了注册ActiveX控件的实用技术。  相似文献   

2.
Windows环境下的USB设备驱动程序设计   总被引:4,自引:0,他引:4  
介绍了Windows环境下的USB设备驱动程序设计方法。通过对WDM驱动程序设计方法的讨论和应用,实现了使用EZ-USB芯片进行计算机通信。  相似文献   

3.
Win32应用程序中进程通信方法分析与比较   总被引:11,自引:4,他引:7  
随着人们对应用程序的要求越来越高,单进程应用在许多场合已不能满足人们的要求,编写多进程/多线程程序成为现代程序设计的一个重要特点,在多进程程序设计中,进程喑的通信是不可避免的。Microsoft Win32API提供了多种进和平是通信的方法,全面地阐述了这些方法的特点,并加以比较和分析,希望能给读者选择通信提供参考。  相似文献   

4.
WinCE红外通信程序设计   总被引:1,自引:1,他引:0  
以WindowsCE为操作系统的掌上电脑的红外通信程序设计方法,分析了实现红外通信的3种不同方式的特点,用实例详细介绍了红外通信程序设计的主要过程.  相似文献   

5.
本叙述了利用现有电话网进行计算机数据通信的系统构成及硬件,介绍了异步串行通信程序设计中的中断机制,流量控制,数据缓冲等关键问题。  相似文献   

6.
PLC与上位机的串行通信程序设计   总被引:2,自引:0,他引:2  
介绍了利用Windows API 函数实现上位机与OMRON C200HG PLC 的通信,并给出了计算机具有优先权时基于VC 的通信程序设计方法。  相似文献   

7.
在许多像计算机远程控制和数据采集这样的应用系统中,通信模块是必不可少的。实现它的模块化设计,能够极大地减轻系统的设计工作。结出了一个通用远程通信模块的电路设计和工作原理,接口时序和通信程序设计的软件流程。介绍了这种远程通信模块的应用。  相似文献   

8.
指出了Microsoft.NET垃圾回收机制的缺陷,给出了在通信程序设计中的解决办法,并详细介绍了Winsock通信动态链接库、视频捕捉动态链接库的编写过程及调用方法,叙述了Microsoft Visual Studio 2005平台下点对点的通信程序设计,最后总结了用Winsock开发应用程序的特点.  相似文献   

9.
介绍了Windows98环境下利用Visual C 6.0的MSComm控件实现微机与微机及微机与单片机通信程序设计方法,并完整给出了微机、单片机的通信程序实例。  相似文献   

10.
一种通用远程控制模块的实现和应用   总被引:2,自引:1,他引:2  
在许多像计算机远程控制和数据采集这样的应用系统中,通信模块是必不可少的。实现它的模块化设计,能够极大地减轻系统的设计工作。给出了一个通用远程通信模块的电路设计和工作原理,接口时序和通信程序设计的软件流程。介绍了这种远程通信模块的应用。  相似文献   

11.
Abstract Information and Communication Technologies (ICT) are now widespread in Australian schools but with variation in how, where, when and how much they are used. Computers may be located in a computer laboratory, distributed throughout the school, or students may use their own laptop computers. IT may be a subject in its own right or ICT may be used across all areas of the curriculum. It is how ICT is used in the school setting that is important in providing students with the skills to be participate in a 'knowledge society'. This paper examines the ways in which information and communication technologies influence teaching and learning in five Australian schools. Data were gathered through observation, interviews and document analysis in schools operating at the elementary and secondary grades in relatively technology rich environments. Each of the schools participated in the Australian component of the Second Information Technology in Education Study – Module 2 (SITES-M2) of innovative pedagogical practices. Several of the studies were of specific projects where ICT was the key enabler of the learning programme. Others focused on an entire school's approach to ICT as an agent for changed approaches to learning.  相似文献   

12.
以全国森林覆盖率最高的福建省为研究对象,利用2000~2017年夏季的MODIS EVI植被指数数据和气象与非气象因子进行协同分析,以揭示近17年福建植被的时空变化及其影响因子。结果表明:研究期内福建的EVI均值整体上升,从2000年的0.454上升至2017年的0.505,17 a间上升了11.2%,表明福建省的植被整体处于变好的状态,且在中部和西南部的变化最明显。相关分析表明,在研究期内,气象因子(气温和降水)对EVI变化的影响不显著,植被的变好主要为非气象因子的作用。EVI的提高主要得益于2003年福建省建设生态省后森林覆盖率的提高,并和2012年开始的水土流失治理有明显关系,这说明人类活动的积极作用对福建植被的变好起到了关键的作用。  相似文献   

13.
In this case study of forms 7–9 in a Swedish school, the subject conceptions of and teaching practices in art subjects of schoolteachers and pupils are studied, in particular with regard to digital media. How the core content of a subject is conceived is compared to the importance of digital media in the teaching practice. For three years a class was followed whose teachers taught the pupils in both the art subject and in a local optional subject called Media. The method of triangulation involving participant observations, focus talks, interviews and questionnaires was employed in order to study the role of digital media in different subjects and their actual use by pupils. The results show that the school subject paradigm in the subject of art is chiefly connected to image production for developing aesthetic-practical skills. Traditional manual production is encouraged, thereby contributing to the limited use of digital media in the subject of art. Frame factors such as time and material also contribute to the limited use of digital media in the subject of art. Unlike the subject of art, the optional subject of media is conceived of more as a communication subject, and digital technology for image production is encouraged. In general, the use of digital media in the school is mainly guaranteed by the school's media plan. The role of the art subject is not prominent in this plan, but its teachers are active in implementing digital media in other contexts than within the framework of the art subject. In this study the representatives of the subject of art hardly used digital image processing at all in their teaching, but did so to a great extent in the optional subject of media. This made it clear that digital media in the subject of art in this school are not regarded as a prioritised media-specific competence. Offering and being able to provide a larger repertoire of digital media in the teaching of art could contribute to a change of the subject paradigm in a more clearly communicative than aesthetic-practical direction.  相似文献   

14.
Abstract The term 'desktop publishing' has received much media coverage in recent months in both the commercial and educational press. School-based 'desktop publishing' packages are at the moment poor imitations of full-specification systems. This paper discusses the state of desktop publishing in education today and demonstrates the weaknesses of the systems available for use in the classroom. The skills required for desktop publishing are interrelated in a complex way and cannot be presented in a hierarchical fashion. A model of the functional processes involved is suggested in the paper and analysed in terms of the skills required.  相似文献   

15.
关联规则挖掘技术研究进展*   总被引:5,自引:2,他引:3  
为帮助人们深入研究关联规则挖掘技术,总结了关联规则的分类方法、评价方法以及相关技术的最新进展,特别是对关联规则的主要算法进行了详细的介绍,并探讨未来的发展方向。该研究比较系统全面,对将来进一步深入分析关联规则挖掘技术具有指导意义。  相似文献   

16.
Summary Algorithms for mutual exclusion that adapt to the current degree of contention are developed. Afilter and a leader election algorithm form the basic building blocks. The algorithms achieve system response times that are independent of the total number of processes and governed instead by the current degree of contention. The final algorithm achieves a constant amortized system response time. Manhoi Choy was born in 1967 in Hong Kong. He received his B.Sc. in Electrical and Electronic Engineerings from the University of Hong Kong in 1989, and his M.Sc. in Computer Science from the University of California at Santa Barbara in 1991. Currently, he is working on his Ph.D. in Computer Science at the University of California at Santa Barbara. His research interests are in the areas of parallel and distributed systems, and distributed algorithms. Ambuj K. Singh is an Assistant Professor in the Department of Computer Science at the University of California, Santa Barbara. He received a Ph.D. in Computer Science from the University of Texas at Austin in 1989, an M.S. in Computer Science from Iowa State University in 1984, and a B.Tech. from the Indian Institute of Technology at Kharagpur in 1982. His research interests are in the areas of adaptive resource allocation, concurrent program development, and distributed shared memory.A preliminary version of the paper appeared in the 12th Annual ACM Symposium on Principles of Distributed ComputingWork supported in part by NSF grants CCR-9008628 and CCR-9223094  相似文献   

17.
Spatial heterogeneity in ecosystem functioning is a key component of ecological variability requiring special attention in the context of global change. A large history of human use has produced high physiognomic heterogeneity in Mediterranean ecosystems. However, the consequences for ecosystem functioning remain insufficiently understood. We analyzed spectral indicators of matter and energy fluxes in the land surface to classify the functional ecosystem heterogeneity in a Mediterranean region covering different management histories and protection types. We specifically analyzed the spatial variability in seasonal and annual patterns in the Normalized Difference Vegetation Index (NDVI), surface temperature (Ts) and albedo from five Landsat ETM images. Then we classified numerically this variability into ecosystem functional types (EFTs) and explored their seasonal dynamics in terms of photosynthetic radiation absorption and evapotranspiration. We identified eight main EFTs with ecologically relevant differences including contrasting dynamics in fPAR seasonality, great variation in incoming radiation reflection and differing evapotranspiration rates, particularly during the water-limitation period. Functional variability in natural vegetation mostly consisted in dissimilar annual rates of NDVI and albedo, whereas differences in seasonality were more evident in transformed areas. Similarly, the spatial distribution of EFTs was partly associated to protection, with two EFTs exclusive of protected areas and comparatively higher functional diversity in humanized areas. Landform effects on water availability in protected areas and human activities under different ecological settings were seemingly responsible for the large functional diversity of the region. We advocate for the explicit incorporation of multifunctional ecosystem heterogeneity in ecosystem management and monitoring designs.  相似文献   

18.
Multi-temporal Moderate Resolution Imaging Spectroradiometer (MODIS) data was used to estimate the spatial distribution of heading date and rice-cropping system employed in the Mekong Delta relative to seasonal changes in water resources in 2002 and 2003. We improved a Wavelet-based Filter for determining Crop Phenology (WFCP) and developed a Wavelet-based Filter for evaluating the spatial distribution of Cropping Systems (WFCS) to the interpretation of MODIS time-series data to determine the spatial distribution of rice phenology and various rice-cropping systems from the seasonal Enhanced Vegetation Index (EVI) data. The findings correspond well the physical characteristics of the cropping system in the Mekong Delta, which have changed over time in response to localized and seasonal changes in water resources. One such example is the double-irrigated rice-cropping system commonly employed in the upper Mekong Delta in the dry season to avoid damage due to the subsequent floods. The shortage of suitable irrigation water and intrusion of saline water in the coastal regions during the dry season has constrained the practice dry-season cropping and has meant that the double- and single-rainfed rice-cropping systems are employed in the rainy season. A triple-irrigated rice-cropping system is used in the central part of the Mekong Delta which is located midway between the flood-prone and salinity intrusion areas. Analysis of annual changes in the rice cropping systems between 2002 and 2003 showed that the triple-cropped rice expanded to the flood- and salinity-intrusion areas. This expansion indicates that the implementation of measures to limit the extent of flooding and salinity intrusion by improved farming technologies and improvements in land management. The heading dates in the upper Mekong Delta in 2003 were earlier than in 2002 by approximately 20 to 30 days. The reasons for this would be due to decreased flood runoff in 2002 compared to 2001, and implementation of government policies regarding early sowing of dry-season crops. Subsequent analysis of the MODIS data confirmed that the spatial distribution of rice-cropping systems was closely related to seasonal changes in river runoff regime in the Mekong Delta.  相似文献   

19.
随着机器学习在社会中的广泛使用,带来的歧视问题引发广泛的社会争议,这逐步引起了产业界和学术界对机器学习算法公平性问题的浓厚兴趣。目前对公平性度量和机器学习公平性机制的研究仍然处于初级阶段。本文对公平性机器学习的研究进行了调研,首先从公平性的定义出发,比较了衡量公平性指标的方法,然后调研了公平性数据集,对公平性问题的产生进行了分析,接下来对现有的公平性机器学习算法进行归类和比较,最后总结了当前公平性机器学习研究中存在的问题,并对关键问题和重大挑战进行了讨论。  相似文献   

20.
基于欧空局的GlobSnow雪水当量数据集和国家青藏高原科学数据中心的北半球长时间序列雪深数据集NHSD研究了北半球及9个典型区的雪深时空分布与变化特征。结果表明:北半球1988~2018年平均雪深总体呈显著下降趋势(p<0.01),年际变化幅度为-0.55 cm·(10 a)-1。在高纬度地区,加拿大北部和阿拉斯加年平均雪深下降明显(p<0.01),下降速率分别为3.48 cm·(10 a)-1和3 cm·(10 a)-1,两地区月平均雪深在冬季显著下降。西西伯利亚平原和东欧平原年平均雪深呈下降趋势,其中东欧平原雪深下降较为明显(p<0.01),变化速率为-2.3 cm·(10 a)-1,两地区的月平均雪深在春季显著下降,其中5月份最为明显。东西伯利亚山地的雪深年际变化呈增加趋势,除堪察加半岛外,其月平均雪深在冬季呈显著增加趋势。对于高山区,阿尔卑斯山脉和落基山脉的年平均雪深呈缓慢增长趋势,而青藏高原地区雪深呈缓慢下降趋势。阿尔卑斯山脉的月平均雪深在冬季呈显著增加趋势,5月份显著减小。落基山脉和青藏高原雪深变化呈现出空间异质性:在整个研究时段,落基山脉北部月平均雪深呈下降趋势,中部和南部呈上升趋势;青藏高原的北部边缘山脉雪深呈显著上升趋势,中部大多数地区呈下降趋势。喜马拉雅山脉的北坡雪深增加,南坡雪深减小,但其变化率绝对值小于0.5 cm·a-1。东南部雪深较大的念青唐古拉山脉冬季雪深呈显著下降趋势。对9个典型区雪深的年内分析(2001~2010年平均值)结果显示:高山区雪深峰值远低于高纬度地区雪深峰值。除青藏高原外,高山区的积雪融化起始日期明显早于高纬度地区。  相似文献   

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