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81.
基于视觉行为的手机新闻App图文布局设计研究 总被引:1,自引:0,他引:1
通过实例总结出手机新闻App的三种基础图文布局结构,即左图右文式、左文右图式和上文下图式布局。以图文布局结构的客观评价为目的,从视觉搜索和视觉浏览规律的角度,分析了手机新闻App图文布局结构对用户阅读效率的影响。运用眼动仪对三种图文布局方案进行了实验评价与分析。通过注视轨迹、注视热点、注视点数量和搜索时间,研究不同图文布局方案下视觉浏览和视觉搜索的眼动规律。实验发现用户使用手机新闻App呈现文字导向型的视觉浏览规律,上文下图式图文布局的视觉搜索效率最高。研究结论可为手机新闻App图文布局设计提供科学的参考依据。 相似文献
82.
为了提高食品检测效率,改善食品检测精度,增加食品检测的客观性,文章介绍了一种基于6-UPS机构的咀嚼机器人,介绍了咀嚼机器人的结构原理,求解了机构的运动学逆解,分析了机构的工作空间影响因素,利用MATLAB编程求得机构在定姿态下的工作空间。空间轮廓图表明,该机构在定姿态下能到达人类全部真实咀嚼空间,机构设计可靠,能够模拟人类咀嚼行为对食品进行检测。 相似文献
83.
为了减少在产品包装环节中的人员参与,提高包装环节的自动化程度,研制了一种用于立体标签的自动贴标机。
根据产品贴标的流程,采用Pro/E软件进行三维建模和零部件的优化设计,包括传送机构、标签推进机构和折弯机构。
折弯机构中采用了折弯翻板实现对标签的折弯控制;自动贴标机各机构均采用了独立的电机控制,控制系统采用PLC
技术和变频器调速控制,设计了电动机正反转的控制电路图。通过对机械结构和电气控制系统优化设计,得到了满足设
计要求的自动贴标机机构设计参数,实现了对厚度为0.5 mm纸质标签纸的2次折弯并实现贴标过程。该自动标签机的
使用实现了包装过程的自动化,提高产品的包装效率。 相似文献
84.
A Rejection Principle for Sequential Tests of Multiple Hypotheses Controlling Familywise Error Rates 下载免费PDF全文
We present a unifying approach to multiple testing procedures for sequential (or streaming) data by giving sufficient conditions for a sequential multiple testing procedure to control the familywise error rate (FWER). Together, we call these conditions a ‘rejection principle for sequential tests’, which we then apply to some existing sequential multiple testing procedures to give simplified understanding of their FWER control. Next, the principle is applied to derive two new sequential multiple testing procedures with provable FWER control, one for testing hypotheses in order and another for closed testing. Examples of these new procedures are given by applying them to a chromosome aberration data set and finding the maximum safe dose of a treatment. 相似文献
85.
When studying associations between a functional covariate and scalar response using a functional linear model (FLM), scientific knowledge may indicate possible monotonicity of the unknown parameter curve. In this context, we propose an F-type test of monotonicity, based on a full versus reduced nested model structure, where the reduced model with monotonically constrained parameter curve is nested within an unconstrained FLM. For estimation under the unconstrained FLM, we consider two approaches: penalised least-squares and linear mixed model effects estimation. We use a smooth then monotonise approach to estimate the reduced model, within the null space of monotone parameter curves. A bootstrap procedure is used to simulate the null distribution of the test statistic. We present a simulation study of the power of the proposed test, and illustrate the test using data from a head and neck cancer study. 相似文献
86.
文福安 《北京邮电大学学报(社会科学版)》2007,9(2):25-28
本文通过对我国网络教育软件市场规模分析和针对网络教育软件系统的应用情况调查,得出网络教育软件发展趋势,提出网络教育软件产业需要走集成化、协作化、统筹规划、资源共享道路,要形成以学生为中心的授课、练习、测验、答疑全面协调互动的网络教学体系,并通过技术手段进行强化网络教育的教学质量。 相似文献
87.
88.
We extend four tests common in classical regression – Wald, score, likelihood ratio and F tests – to functional linear regression, for testing the null hypothesis, that there is no association between a scalar response and a functional covariate. Using functional principal component analysis, we re-express the functional linear model as a standard linear model, where the effect of the functional covariate can be approximated by a finite linear combination of the functional principal component scores. In this setting, we consider application of the four traditional tests. The proposed testing procedures are investigated theoretically for densely observed functional covariates when the number of principal components diverges. Using the theoretical distribution of the tests under the alternative hypothesis, we develop a procedure for sample size calculation in the context of functional linear regression. The four tests are further compared numerically for both densely and sparsely observed noisy functional data in simulation experiments and using two real data applications. 相似文献
89.
Testing an Integrative Contextual Career Development Model With Adolescents From High‐Poverty Urban Areas 下载免费PDF全文
Julia L. Conkel‐Ziebell Sherri L. Turner George V. Gushue 《The Career development quarterly》2018,66(3):220-232
Variations in the economic recovery rate across the United States have led to even greater chasms that separate the employed, unemployed, and underemployed (DeSilver, 2017 ). Therefore, understanding and supporting the career development of future generations is critical—especially for those who live outside the context of social privilege. The authors examined the applicability of the integrative contextual model of career development (ICM; Lapan, 2004 ) to a sample of 220 adolescents (129 boys, 91 girls) from a high‐poverty urban area. Results indicated that a canonical variate comprising foundational ICM skills (e.g., career exploration, goal setting) predicted a variate composed of ICM outcomes (e.g., self‐efficacy, vocational identity), thus supporting the usefulness of the ICM framework for this population. The skill of setting viable career goals was an especially strong predictor of outcomes. Implications for career counseling with adolescents living in high‐poverty urban areas and directions for future research are discussed. 相似文献
90.