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91.
肤色测量在基于颜色特征的人脸识别、皮肤科临床和美容护肤等领域有着广泛的应用。文中应用数字图像处理技术在HSV色彩空间中对影响肤色测量的几个环境因素进行了实验研究。研究发现,人类皮肤的饱和度S和亮度V对电压波动呈现出较好的鲁棒性,而色调H受电压稳定性的影响相对较大。研究还发现,特征参量( S+V)/H会随着温度的降低而减小,随着湿度的减小而增加,受测量环境温、湿度的影响较大。同时研究结果表明参量( S+V)/H对颜色的变化具有较强的分辩能力,可以较好地描述红斑类和白斑类皮肤病的颜色变化过程。  相似文献   
92.
自尊是个体在社会比较过程中获得的有关自我价值的积极评价与体验。自从自尊的概念被提出以来,自尊的研究就一直受到心理学家们的重视,成为心理学研究的一个重要领域。自尊对个体的认知、情绪、心理健康和个性发展均有着重要的影响。通过对以往的研究进行分析、归纳和总结,结果发现:对自尊的研究主要集中在概念、结构、发展特点、测量及其与心理健康的关系等方面,其中自尊的结构和自尊与心理健康关系的研究是自尊研究的重点。本文从这五个方面对不同时期自尊研究所面临的主要问题及所取得的重要研究成果进行梳理,在把握自尊整体发展脉络的基础上力图对自尊未来的发展趋势进行展望。  相似文献   
93.
This paper reports the development and validation of a short Use of Creative Cognition Scale in Studying (UCCS) that was inspired by the Cognitive Processes Associated with Creativity (CPAC) scale. In Study 1, items from two of the six subscales of the CPAC were excluded due to conceptual and psychometric issues to create a 21-item CPAC scale, which was administered to 517 university students. Exploratory factor analysis revealed that the 21-item CPAC scale is unidimensional. Five items were selected to create the new unidimensional UCCS. In Study 2, 696 students completed the UCCS and a set of scales measuring related constructs. Confirmatory factor analysis corroborated the unidimensional structure of the scale. The scale correlated positively with measures of flow, trait intrinsic motivation, adaptive metacognitive traits and positive affect, it correlated negatively with negative affect, and it did not correlate with core maladaptive metacognitive traits. The findings indicate that the scale is a valid and reliable tool for research and monitoring.  相似文献   
94.
This study aims to explore the relationships between the extent and perceived quality of teachers’ experience of training in behaviour management (BM), and their awareness of the nature and extent of behavioural problems among school students, and their confidence in their own competence to deal with such problems. Teachers (n = 183) from Hong Kong primary schools were surveyed. The results showed that gender, age and whether teachers have received training had no significant influence on teachers’ awareness, conception and confidence regarding BM. A negative correlation was found between teachers’ levels of satisfaction in relation to their training experiences and their perceptions of the level of problematic behaviours among students, and the impact of students’ problematic behaviour on their teaching. A positive correlation was found between teachers’ levels of satisfaction in relation to their training experiences and their confidence in their own competence to deal with students’ problematic behaviour.  相似文献   
95.
鉴于长江流域环境保护在我国转型发展中的重要战略地位,为定量研究长江流域碳排放量的变化趋势,文章在齐绍州和付坤建立的测算方法基础上,建立了分行业、分省区、分时段测算长江流域的碳排放量及其增长率的测算方法。长江流域碳排放量的结构及其增长率变化趋势表明,总的碳排放量增长率正在不断下降。这是由于长江流域各省区正在大力发展交通、物流、通讯业等惠及民生的产业,政府系列政策的实施效果不断得到体现。  相似文献   
96.
Test developers and psychometricians have historically examined measurement bias and differential item functioning (DIF) across a single categorical variable (e.g., gender), independently of other variables (e.g., race, age, etc.). This is problematic when more complex forms of measurement bias may adversely affect test responses and, ultimately, bias test scores. Complex forms of measurement bias include conditional effects, interactions, and mediation of background information on test responses. I propose a multidimensional, person-specific perspective of measurement bias to explain how complex sources of bias can manifest in the assessment of human knowledge, skills, and abilities. I also describe a data-driven approach for identifying key sources of bias among many possibilities—namely, a machine learning method commonly known as regularization.  相似文献   
97.
Students with autism may struggle to develop the academic skills necessary for success in school and beyond. Understanding and improving academic skills performance requires appropriate measurement approaches. One such option that has been minimally studied with students with autism is curriculum-based measurement (CBM). Coinciding with the need to study different approaches to academic skills measurement for students with autism was the global pandemic which forced a shift to remote service delivery with little warning. While some autistic students struggled with this shift, others thrived, raising questions about how to further support students with autism in virtual formats. The purpose of this study was to examine the feasibility of using remotely administered CBM for autistic students by studying both the practicality and acceptability of this approach. Five students with autism (Grades 2–5) participated in this pilot study, completing reading, math, and writing CBMs at three time points. Student behavior and assessor fidelity were collected to examine practicality; assessor ratings of usability provided insight regarding the acceptability of the approach. Results indicated that remotely administered CBM is feasible for some students with autism: all participants completed the study tasks with minimal behavioral difficulties, and assessor ratings of acceptability were high.  相似文献   
98.
In this paper we report upon a first empirical exploration of the relative efficiency of innovation development by product users vs. product producers. In a study of over 50 years of product innovation in the whitewater kayaking field, we find users in aggregate were approximately 3× more efficient at developing important kayaking product innovations than were producers in aggregate. We speculate that this result is driven by what we term “efficiencies of scope” in problem-solving. These can favor an aggregation of many user innovators, each spending a little, over fewer producer innovators benefitting from higher economies of scale in product development. We also note that the present study explores only one initial point on what is likely to be a complex efficiency landscape.  相似文献   
99.
食品安全问题是民生问题,随着"绿色"这一概念在人们脑海里的深入,果蔬作为人们生活中不可或缺的食品,其农药残留超标问题也越来越受到大家的关注。对一些有特殊人群存在的家庭而言,农药残留超标问题确实迫在眉睫。研究和设计家用农药检测机有助于人们真正快速有效的解决果蔬农药残留问题。文章分析农药残留速测卡的特点,针对速测卡的优缺点设计一款家用农药残留速测机。  相似文献   
100.
本文介绍了一种带有非线性器件的射频通道天线的测试方法,针对这一种类型的天线系统,构建了一种收发不同频的天线测试系统。基于已有的室内天线远场测试系统,在不改变原有远场系统硬件配置以及软件系统的基础上,只添加一套对应的混频装置,就可完成对带有发射上变频与接收下变频通道的天线测量。系统的改造方案具有一定的通用性。在工程上对内置频率转换器件的这一类型天线方向图的精确测量具有一定的借鉴意义。  相似文献   
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