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71.
提出一种直接以AOV(Activity On Vertex)图存储PLC(Programmable Logic Controller)梯形图的方法。编辑梯形图的同时,修改AOV图,然后根据AOV图的拓扑结构更新梯形图图符坐标,最后进行绘制显示。该方法无需进行梯形图向AOV图的转换,通过操作规则的约束来替代语法的检查,使梯形图的编辑更加便捷和规范。详细介绍了AOV图的编辑过程和坐标的更新算法。对AOV图向二叉树的转换算法进行修改,使其能适应于所有AOV图,并给出了相应的实例。  相似文献   
72.
产学模式在《数据库原理》课程教学改革中的应用   总被引:1,自引:0,他引:1  
谷伟  陈莲君  徐方勤 《软件》2012,(7):153-155
针对目前《数据库原理》课程采用传统教学模式存在的诸多问题,就如何提高应用型本科计算机专业学生对《数据库原理》课程的学习兴趣和解决实际问题的能力,提出了产学相结合的数据库原理课程教学模式,首先让学生在工程化环境中进行相关理论学习,同时提供课程网站等辅助手段进行扩展学习,在此基础上根据企业的实际需求模拟环境让学生进行实践,并对其实践展开了进一步讨论。  相似文献   
73.
论述了三弧段型面曲线的形成及其曲线参数方程,编制了三弧段型面的数控加工宏程序,适用于各种不同参数的三弧段型面的加工,且能够满足加工精度的要求。  相似文献   
74.
The executive attention theory of working memory capacity (WMC) proposes that measures of WMC broadly predict higher order cognitive abilities because they tap important and general attention capabilities (R. W. Engle & M. J. Kane, 2004). Previous research demonstrated WMC-related differences in attention tasks that required restraint of habitual responses or constraint of conscious focus. To further specify the executive attention construct, the present experiments sought boundary conditions of the WMC-attention relation. Three experiments correlated individual differences in WMC, as measured by complex span tasks, and executive control of visual search. In feature-absence search, conjunction search, and spatial configuration search, WMC was unrelated to search slopes, although they were large and reliably measured. Even in a search task designed to require the volitional movement of attention (J. M. Wolfe, G. A. Alvarez, & T. S. Horowitz, 2000), WMC was irrelevant to performance. Thus, WMC is not associated with all demanding or controlled attention processes, which poses problems for some general theories of WMC. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
75.
介绍了一款语音压缩专用处理器的设计思路,使用嵌入式FLASH超长指令字系统有效的提高了芯片的处理能力,同时将增强型算术逻辑单元、乘法器、乘累加器结合在一起,在改进的哈佛体系结构上实现了微控制器与DSP的单核设计。使用存储器操作指示寄存器、分层寄存器组,能够简化子程序调用方式。该微处理器采用0.25μm CMOS工艺实现,芯片面积为25mm^2。仿真结果表明,在20MHz工作频率下,芯片处理能力与50MIPS的通用DSP相当,同时能够保持原有编码质量。该处理器能够实现多种类型的语音压缩算法,可以达到对语音算法的高保密性、低复杂度、易开发性。  相似文献   
76.
提出了文检课个性化教学的观点,讨论了实施个性化教学的必要性,指出在网络环境下,如何构建多维的个性化智能教学系统,探讨了个性化的教学方案及基于此的教学内容及考试制度。  相似文献   
77.
The way we look at problems affects how we study them and try to solve them. Different interventions become salient depending on whether we focus on individuals perceived to have the problem, on the social setting that fosters it, or on an interaction of the two. As psychologists, our training is conducive to thinking on the individual rather than on the system level. When we employ research strategies that personalize the political, we risk being complicit with conservative political agendas that avoid social change by focusing on individual dysfunction. Even community psychologists, despite dealing in system-level theories, too often transform these into individual-level research. I will use, as examples, poverty, drugs, homelessness, resilience, and empowerment. I argue that since our research can provide a justification for either changing or maintaining the status quo, it has ethical implications. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
78.
79.
Sexually dimorphic cognitive performance in men (n=42) and women (n=42) was related to testosterone, estradiol, progesterone, luteinizing hormone, follicle-stimulating hormone, and sex hormone binding globulin, measured in 10-ml blood samples collected between 0900 and 1030 and, among women, during the follicular phase of the menstrual cycle. Significant sex differences favored men on spatial tasks (Mental Rotation and Judgment of Line Orientation) and on an inhibition task and favored women on a verbal task (category fluency). However, there were no significant relationships between any of the hormones and cognitive performance, suggesting that there are few, if any, consistent, substantial relationships between endogenous, nonfluctuating levels of gonadal hormones or gonadotropins and these cognitive abilities in men or women. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
80.
Reviews the book Protecting children from domestic violence: Strategies for community intervention, edited by Peter J. Jaffe, Linda L. Baker, and Alison J. Cunningham (see record 2005-04430-000). The book emerged from the International Conference on Children Exposed to Domestic Violence that was held in London, Ontario in 2001. It begins with an excellent chapter by Jeffrey Edleson synthesizing the literature on the impact of exposure to domestic violence on children. Edleson's chapter is followed by two papers examining emerging assessments and treatment programs. The second section of the book addresses current thinking about individual and group intervention approaches. The third section of the book examines broader system level responses, including public awareness and school-based campaigns, as well as responses by the courts and police. This is a well-organized collection of papers that provides a good overview of the state of knowledge and innovative practice in an emerging field of practice. Protecting Children from Domestic Violence provides practitioners, policy makers, and researchers with an excellent overview of current knowledge and practices in working with children exposed to domestic violence. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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