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排序方式: 共有584条查询结果,搜索用时 15 毫秒
1.
根据人体运动图像的特点,引用图像层的平滑处理和图像层的边缘处理获得了较好的人体运动边缘图像,通过轮廓跟踪能较好地提取了人体运动图像边缘,为研究人体运动图像质心定位作好了准备。同时也为处理人体运动图像提供了一种新的方法。  相似文献   
2.
Previous studies have documented social segregation for single types of tracking, but little previous research has compared levels of segregation across different institutional tracking arrangements. This paper uses extensive administrative data of the Chilean educational system to estimate the magnitude and evolution of socioeconomic segregation between- and within-school curriculum tracking. Results indicate that the unequal distribution of students by socioeconomic status between tracks narrows when tracking takes place within schools, mainly in the presence of market incentives that lead schools to focus on particular student populations.  相似文献   
3.
The purpose of this article was to examine the validity of self-reported pedometer steps/day. Forty-seven participants were provided a New Lifestyles NL-2000 (NL-2000; Lees Summit, MO, USA) pedometer and a physical activity (PA) diary for 3 weeks, but not informed of the data-storing capabilities. For weeks 2 and 3, each participant was given a step goal of 3,000 steps/day above week 1 average. A 2 × 3 repeated measures analysis of variance (ANOVA) was used to examine differences between reported steps/day. Bland–Altman plots assessed the mean bias and limits of agreement between reporting methods. Mean self-reported and NL-2000 steps/day were 9,264 ± 3,555 and 8,971 ± 3,590 steps/day (n = 26, p > .05). Mean biases were 216 ± 1,753 (week 1), –506 ± 1,355 (week 2), and –590 ± 1,360 (week 3) steps/day. Negative mean bias values indicate higher self-reported steps/day. Mean steps/day were similar between recording methods, but large differences were observed among individuals, suggesting self-reported steps/day may be valid for PA research at the population level, but not the individual level.  相似文献   
4.
建设项目全过程跟踪审计是接受业主委托,对工程项目进行全过程的跟踪审计工作。其具体内容包括在工程招标阶段协助业主起草招标文件提供咨询服务;在工程施工阶段参加图纸会审,现场勘查,隐蔽工程验收,工程变更、洽商、签证的确认,工程进度拨款的控制,以及最后对工程结算进行的审核。对工程进行全面、详细的跟踪审计工作,协助业主实现建设项目投资控制目标,以便最大的发挥业主投资效益。  相似文献   
5.
Corporate restructuring was identified as a new industrial force that has great impact on economic values and that therefore has become central in daily financial decision making. This article investigates the optimal restructuring strategies under different dynamic factors and their numerous impacts on firm value. The concept of quasi-leverage is introduced and valuation models are built for corporate debt and equity under imperfect market conditions. The model's input variables include the quasi-leverage and other firm-specific parameters, the output variables include multiple corporate security values. The restructuring cost is formulated in the form of exponential function, which allows us to observe the sensitivity of the variation in security values. The unified model and its analytical solution developed in this research allow us to examine the continuous changes of security values by dynamically changing the coupon rates, riskless interest rate, bankruptcy cost, quasi-leverage, personal tax rate, corporate taxes rate, transaction cost, firm risk, etc., so that the solutions provide useful guidance for financing and restructuring decisions.  相似文献   
6.
提出一种针对城市快速路的视频监控系统,完成交通流及道路异常行为检测.流量检测模块对车辆进行实时跟踪获得各类交通流统计数据,实现快速路车辆运行状况的全面掌控.异常监控模块运用隐马尔科夫模型,对带有时间和空间信息的车辆轨迹进行训练,获得路径划分后对道路车辆轨迹进行参数匹配,提取诸如超低(高)速行驶、违章停车、违规掉头等异常...  相似文献   
7.
在对204名大四学生采取问卷调查的基础上,探讨了大学生职业自我效能、职业价值观与就业能力的关系,结果表明:(1)职业自我效能、职业价值观和就业能力中的职业成长能力存在显著相关.(2)文科生的职业自我效能、就业能力高于理科生.(3)高职业自我效能和高职业价值观的大学生的就业能力均高于低自我效能和低职业价值观的大学生.(4)职业决策自我效能在职业价值观和就业能力之间起中介作用.  相似文献   
8.
ABSTRACT

The focus of much mathematics teaching has been on the acquisition of counting, an area where children with Down syndrome can experience particular difficulties. Research with typically developing children has highlighted how early awareness of quantity provides a strong platform for the acquisition of later mathematical skills and programmes of early intervention have been introduced. Many of these studies are embedded in the work and traditions of developmental and cognitive psychology and can be difficult to access. Consequently, this is an area that has been largely ignored in the curricula of children with Down syndrome. This paper seeks to make this literature more available. It systematically reviews previous research with children with Down Syndrome on these early foundations. It considers seemingly contradictory findings in the light of differences in tasks, their presentation and instructions, and the responses required, in order to draw conclusions and reflect on the implications for teaching and learning. Some of these propositions are in contrast to existing practices and call for further research to test their effectiveness.  相似文献   
9.
The global expansion of mass schooling has greatly increased opportunities for low-income families, and governments have devoted much effort to equalising access and quality in education systems. Alongside regular schooling, the so-called shadow education system of private supplementary tutoring has grown rapidly across the world. The fact that rich families can purchase more and better quality shadow education undermines the achievements of increased equality of opportunities in formal schooling. Drawing on a mixed-methods study in Shanghai, China, the article shows how shadow education has offset school equalisation policies through differentiation of access and through sorting mechanisms. Shadow education occupies a space beyond strict government control in which privileged families and elite schools ignore and mediate the equalisation policies, seeking competitive advantages. Uneven access to shadow education and tracking within it shape, maintain, and exacerbate inequitable schooling experiences at individual and institutional levels.  相似文献   
10.
为了提高低信噪比条件下再生伪码测距系统中的复合伪码时钟恢复性能,采用了一种新型的码片跟踪环.此码片跟踪环是一种改进型的数据转换跟踪环,两者之间的区别在于,码片跟踪环的Q路输出直接乘上了时钟分量,而数据转换跟踪环乘上了I路的转换检测器输出.在准方波伪码测距信号的情况下,详细分析了码片跟踪环的跟踪(均方定时抖动)性能.分析对比了不同码片信噪比条件下的码片跟踪环和数据转换跟踪环跟踪性能.分析表明,码片跟踪环和数据转换跟踪环在大信噪比条件下性能一致;而在小信噪比条件下,码片跟踪环性能明显好于数据转换跟踪环.  相似文献   
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