Software review

STATISTICA 5.0. StatSoft, 2325 East 13th Street, Tulsa, OK 74104, (918) 583–4149. $995 retail, academic site license—$2,000 for 10 copies. Requirements: 386 or better, 4 Meg RAM, Microsoft Windows 3.1 or 95.     

Fitting Nonlinear Latent Growth Curve Models With Individually Varying Time Points

Individual growth trajectories of psychological phenomena are often theorized to be nonlinear. Additionally, individuals’ measurement schedules might be unique. In a structural equation framework, latent growth curve model (LGM) applications typically have either (a) modeled nonlinearity assuming some degree of balance in measurement schedules, or (b) accommodated truly individually varying time points, assuming linear growth. This article describes how to fit 4 popular nonlinear LGMs (polynomial, shape-factor, piecewise, and structured latent curve) with truly individually varying time points, via a definition variable approach. The extension is straightforward for certain nonlinear LGMs (e.g., polynomial and structured latent curve) but in the case of shape-factor LGMs requires a reexpression of the model, and in the case of piecewise LGMs requires introduction of a general framework for imparting piecewise structure, along with tools for its automation. All 4 nonlinear LGMs with individually varying time scores are demonstrated using an empirical example on infant weight, and software syntax is provided. The discussion highlights some advantages of modeling nonlinear growth within structural equation versus multilevel frameworks, when time scores individually vary.     

Learning Visualization Strategies: A qualitative investigation

The following study investigates the range of strategies individuals develop to infer and interpret cross-sections of three-dimensional objects. We focus on the identification of mental representations and problem-solving processes made by 11 individuals with the goal of building training applications that integrate the strategies developed by the participants in our study. Our results suggest that although spatial transformation and perspective-taking techniques are useful for visualizing cross-section problems, these visual processes are augmented by analytical thinking. Further, our study shows that participants employ general analytic strategies for extended periods which evolve through practice into a set of progressively more expert strategies. Theoretical implications are discussed and five main findings are recommended for integration into the design of education software that facilitates visual learning and comprehension.     

WCDMA关键技术的研究简

WCDMA技术的设计目标是不仅能够提供比第二代移动通信系统更大的容量和更好的通信质量．而且要能在全球范围内更好地实现无缝漫游并为用户提供语音、数据和移动多媒体等业务。与第二代移动通信相比,WCDMA系统采用直扩序列码分多址技术（DS—CDMA）,信息被扩展成3．84Mchip／s后在5MHz带宽内传送,同时采角了多种关键技术保证业务质量（QoS）。概括来说,WCDMA关键技术主要包括RAKE接收技术、无线资源管理技术、多用户检测技术和智能天线技术等。     

复杂设备的三维结构交互式演示系统开发——以焦炉为例

以焦炉为例,介绍了一种复杂设备的三维结构交互式演示系统开发方法。应用SketchUp建立焦炉各组成部分的三维数字模型,并导出展示其内部结构的图片和动画。应用Authorware制作焦炉结构三维交互演示系统,该演示系统能用大量的三维图像和动画生动形象地展示焦炉各大组成部分的内部结构和基本工作原理。     

基于VRP的中小学虚拟科技馆的设计和实现

中小学虚拟科技馆作为建设数字化校园的一部分,可以使学生在虚拟科技馆中自由浏览,体验或操控虚拟展示的科学技术和产品,弥补实体科技馆的局限,培养学生的科学精神和素养。文章阐述了建设中小学三维立体虚拟科技馆的步骤、虚拟科技馆的数据采集与教学设计、虚拟科技馆建筑与展品的建模与烘培方法以及利用VR-Platform构建虚拟场景、实现虚拟交互控制的方法。     

Activity theory: A framework for design and reporting on research projects based on ICT

We propose using activity theory as a basis for designing and reporting on research projects that focus on information and communication technology (ICT) as a means to support educational processes. Adopting the theory, we describe teaching/learning activities mediated by ICT using a three level analysis: epistemological, methodological, social assistance. The analysis has been applied to the design and reporting of projects in both mathematics education at primary school level and training in technical innovation in commercial enterprises.     

AsCl_3在9mol·L~(-1)盐酸一苯和水一苯相中分配比的测定

本文介绍了笔者设计的测定AsCL_3在9mol·L~(-1)盐酸—苯相的分配比(D_1)和在水—苯相中的分配比(D_2)的简便方法。试验测知,在19℃时,D_1为10.82,D2为0.0180。苯对9mol·L~(-1)盐酸中的As(Ⅲ)的萃取率为91.5％,水对苯相的As(Ⅲ)的反萃取率为98.2％(等体积一次萃取)。     

淮南市3~6岁幼儿各项身体形态分析

为全面了解淮南市幼儿的形态指标、身体素质现状,2010年淮南师范学院与淮南市体育局共同组织了对淮南市幼儿的调查与测试,把测得数据采用《国民体质测定标准手册》中幼儿部分的评定方法与标准进行统计处理。结果表明：淮南市3~6岁幼儿身体形态发育随着年龄的增加,他们的身高与体重值均增加,呈逐年升高趋向;男性幼儿和女性幼儿的身体形态从3岁就呈现出差异,这主要是由遗传决定的,这种差异在7岁以后,伴随着年龄的增长表现更为明显。     

The role of attachment in the relationship between child maltreatment and later emotional and behavioral functioning

The experience of childhood maltreatment is an important predictor of unfavorable emotional and behavioral outcomes. Because little research examined explanatory variables in the relationship between childhood maltreatment experiences and later outcomes, this study examined the role that attachment serves in this relationship. Four hundred twenty-four participants completed questionnaires assessing the variables of interest for this study. Results indicated that both childhood maltreatment experiences (particularly emotional abuse) and attachment (particularly to mothers and peers) are significant predictors of later emotional and behavioral outcomes. Further, attachment contributed unique and significant variance to the relationship between childhood maltreatment experiences and later outcomes. Such findings suggested that secure attachment may serve as a protective factor against maladaptive emotional and behavioral outcomes as children reach emerging adulthood, even in the context of childhood maltreatment experiences. The importance of studying the relationships among these variables is discussed.