在VFP和ACCESS DBMS中导人和导出EXCEL数据

讨论了在Visual FoxPro 6.0(VFP 6.0)和Access 2000数据库管理系统中导入和导出Excel 2000数据的方法,并提出了一些实用的操作经验.     

For Science and Self: Youth Interactions with Data in Community and Citizen Science

In youth-focused community and citizen (YCCS) youth in classrooms and community-based programs produce data that scientists, resource managers and community members will use. This “nested” data situates learners’ scientific activity within larger datasets, projects, and communities, with consequences for youth agency. To document opportunities for agentive learning with data in YCCS, we report on how youth interact with data across eight school and community-based project sites and how youth talk about their data and work. From analysis of 54 participant interviews, we found that youth perceived the data they produced as being used for: (1) broader scientific work, (2) their own learning, and (3) community endeavors. Nested uses of data were most meaningful when youth interacted with end users, were exposed to the larger datasets to which they contributed, or took action linked to data. Not all youth saw, believed, or valued that data would be used by others. Framing of task and purpose, nature of engagement with community users, data production protocols, and level of emphasis on youth-identified questions may contribute to youth perceptions and can foster or undermine conditions for learner agency. The results shed light on when and how conditions for expansive learning and agency get established.     

Complexity and then some: Theories of action and theories of learning in data-informed decision making

This article presents a synthesis of the complexity of using data in education and highlights some of the promise and challenges of adequately understanding data use across the continuum of accountability to instructional influence in the classroom. Several common themes around the complexity of data use were identified: (1) The nature of the data used, (2) the importance and difficulty of educator data capacity building and sense-making, (3) the importance of characteristics of collaboration, (4) the influence of contextual factors of schools, districts and international settings, (5) the potential negative influence of data use in equity considerations, and (6) the difficulty of determining impact of data use and discerning explanations of why data use initiative work some of the times were examined across the articles. This synthesis concludes with a call for an approach to research in data use in education that concurrently engages multiple aspects of the educational system with a focus on multiple levels of theories of learning that address students, teachers, and organizations.     

Installing a System of Performance Standards for National Assessments in the Republic of Trinidad and Tobago: Issues and Challenges

This article explores the challenge of setting performance standards in a non-Western context. The study is centered on standard-setting practice in the national learning assessments of Trinidad and Tobago. Quantitative and qualitative data from annual evaluations between 2005 and 2009 were compiled, analyzed, and deconstructed. In the mixed methods research design, data were integrated under an evaluation framework for validating performance standards. The quantitative data included panelists’ judgments across standard-setting rounds and methods. The qualitative data included both retrospective comments from open-ended surveys and real-time data from reflective diaries. Findings for procedural and internal validity were mixed, but the evidence for external validity suggested that the final outcomes were reasonable and defensible. Nevertheless, the real-time qualitative data from the reflective diaries highlighted several cognitive challenges experienced by panelists that may have impinged on procedural and internal validity. Additional unique hindrances were lack of resources and wide variation in achievement scores. Ensuring a sustainable system of performance standards requires attention to these deficits.     

数据挖掘技术及其应用进展

数据挖掘就是要从数据中抽取出知识。首先阐述了数据挖掘的任务方法，然后论述了数据挖掘面临的问题，给出了建议的研究方向，最后介绍了几个现有的数据挖掘工具和一些与数据挖掘研究相关的资源。     

中小学教师数据素养的发展路径与培养策略

作为加快数据驱动教学范式转型的关键之所在,教师数据素养是教师适应时代发展需求的必备素养。文章首先通过文献梳理,介绍了教师数据素养和教师数据素养培养的相关研究成果;随后,文章分析了教师数据素养培养的理论与实践依据,并以此为指导,设计了中小学教师数据素养的发展路径;最后,文章从师范生教育、数据知识普及、数据素养培训、教学实践示范四个角度,提出了教师数据素养的培养策略。中小学教师数据素养的发展路径与培养策略的提出,能够为中小学教师数据素养的提升提供理论支持与参考依据。     

Achievement and Attitudinal Differences among Students in Regular,Remedial, and Advanced Classes

The collection of data by the National Center for Educational Statistics for the High School and Beyond study offered an opportunity to examine differences in achievement and attitudinal measures among students in regular, remedial, and advanced classes. Groups of low achieving and high achieving sophomores and seniors were identified on the basis of overall grades. Comparisons were made between students in regular and ability-grouped English and mathematics classes. The data were consistent with views that grouping leads to improved achievement and attitude toward subject matter for students in regular and remedial classes. The data were not consistent with a view that remedial group placement leads to poor self-concept or attitude toward school.     

数字化校园建设中教师与学生数据的研究与应用

结合当前高校数字化校园建设中各种应用系统的建设和使用情况,分析了其中学生数据和教师数据的产生及流向,阐述了数据集成和数据访问2种数据处理方式,探讨了学生和教师数据的集成方案和访问思路,并介绍了其应用情况。     

Conceptual change and anomalous data: A case study in the domain of natural sciences

Cognitive conflict has been proposed as a strategy to promote conceptual change. The history and philosophy of science have shown the importance of anomalous data to change scientific theories and to the progress of science. Often, scientists use anomalous data to develop new interpretations that lead to new conceptualizations and finally, to a deep conceptual change. To be aware of contradiction seems to be a first step in the process of conceptual change. A study to explore novice students responses to anomalous data has been carried out. Sixty nine ninth graders, fifty seven eleventh graders and sixty three twelfth graders participated in the study. A paper and pencil task about the origin of life on the Earth was designed. Subjects were divided into two conditions. In condition “A” only anomalous data were presented to the subjects. In condition “A+B”, both anomalous and confirmatory data were presented. Results indicated that younger students were less aware of contradiction than older students when both anomalous and confirmatory data were presented. However, no differences have been found among them when just anomalous data were presented (condition A). Twelfth graders were aware of contradiction in both conditions. Some students’ epistemological beliefs influenced their response to anomalous data. Although no conceptual change (weak or strong restructuring) was achieved, as it could be predicted by the low domain-specific knowledge of the subjects and the complexity of the topic, presenting anomalous data facilitated the achievement of the first steps of the conceptual change process.     

基于USB2.0和FPGA的高速数据采集卡

介绍一种采用USB2.0接口与PC机进行数据传输的高速数据采集卡的设计。采集卡由可变增益放大器对采样信号进行预处理,使用异步并行的A/D转换技术实现40 Msps的数据采集,由FPGA实现时序控制和数据高速FIFO,由内嵌MCU的USB控制器实现USB2.0接口功能。文章给出了硬件的基本结构和软件固件设计的基本方法,并对用FPGA设计FIFO作了重点阐述,同时对使用异步并行A/D转换与使用采样率为40 Msps的ADC器件的采样数据在FIFO内的数据传输进行了时序仿真,分析了仿真结果。     

Non-linear relationship between combustion kinetic parameters and coal quality

Combustion kinetic parameters (i.e., activation energy and frequency factor) of coal have been proven to relate closely to coal properties; however, the quantitative relationship between them still requires further study. This paper adopts a support vector regression machine (SVR) to generate the models of the non-linear relationship between combustion kinetic parameters and coal quality. Kinetic analyses on the thermo-gravimetry (TG) data of 80 coal samples were performed to prepare training data and testing data for the SVR. The models developed were used in the estimation of the combustion kinetic parameters of ten testing samples. The predicted results showed that the root mean square errors (RMSEs) were 2.571 for the activation energy and 0.565 for the frequency factor in logarithmic form, respectively. TG curves defined by predicted kinetic parameters were fitted to the experimental data with a high degree of precision.     

基于PROE的平面度数据处理分析

平面度误差是最常用最重要的形为误差,是经常检验的公差项目之一。作者介绍的方法是将平面度的测量数据导入PROE软件,PROE中建立点和面后利用最小包容区域法求平面度误差,并用传统的数据处理方法进行了验证,最后得出用PROE软件进行平面度数据处理的可靠性和合理性,且便于数据的实时更新。     

Treatments of Missing Data: A Monte Carlo Comparison of RBHDI,Iterative Stochastic Regression Imputation,and Expectation-Maximization

This article describes a Monte Carlo investigation of 4 methods for treating incomplete data. Data sets conforming to a single structured model, but varying in sample size, distributional characteristics, and proportion of data deleted, were randomly produced. Resemblance-based hot-deck imputation, iterated stochastic regression imputation, structured-model expectation-maximization, and saturated-model expectation-maximization were applied to these data sets, and these methods were then compared in terms of their ability to reconstruct the original data, the intact-data variances and covariances, and the population variances and covariances. The results favored the expectation-maximization methods, regardless of sample size, proportion of data missing, and distributional characteristics of the data. The results are discussed with respect to practical considerations in the choice of missing-data treatment, including the possibilities of model misspecification, convergence failure, and the need to make data available to other investigators.     

DMF-CHCl_3体系汽液相平衡数据的测定与关联

为获得二甲基甲酰胺(DMF)与氯仿(CHCl3)精馏分离的基础热力学数据,实验采用改进型的Rose平衡釜测定了DMF-CHCl3体系在760mmHg下的汽液相平衡数据,并分别用NRTL和Margules模型对实验数据进行关联。结果表明:实验数据满足热力学一致性的检验,且NRTL和Margules模型的计算结果与实测结果偏差小,平均绝对误差分别为0.0026和0.0010,平均相对误差分别为1.81%和1.23%,可满足工业精馏工艺过程设计的需要。     

Comparison Between MIR and NIR Spectroscopic Techniques for the Determination of Fat and Protein Contents in Milk

To compare mid-infrared(MIR)and near-infrared(NIR)spectroscopies for the determination of the fat and protein contents in milk,the same sample sets with varying concentrations of fat and protein were measured in the MIR range of 3 200-700 cm-1 and NIR range of 9 000-4 000 cm-1.The spectral features in the two regions were analyzed.The MIR spectra of milk were characteristic due to the MIR inherent molecular specificity,whereas the NIR spectra were relatively characterless due to the NIR low selectivity.Partial least squares(PLS)regression models for fat and protein were developed by using both MIR and NIR spectra.MIR data with no pretreatment gave better results than NIR data.The square correlation coefficient(R2)and the root mean square error of prediction(RMSEP)were 0.98 and 0.10 g/dL for fat and 0.97 and 0.11 g/dL for protein.With NIR techniques,satisfactory results were not obtained with raw data.However,NIR data after pretreatment gave similarly good results to the ones using MIR method.This paper indicates that either of the MIR and NIR spectral methods is reliable for the determination of the fat and protein contents.     

分布式入侵检测系统数据概化和探查

为适应高速网络的发展,入侵检测系统从传统架构向分布式架构的转换势在必行。本文分析构建了一个分布式入侵检测系统框架模型,提出用数据概化的方法将大量松散数据内聚,来评估计算机网络的安全,并用数据探查的方法追踪在概化数据中显示的不安全因素。使用数据概化和探查可以提高控制中心的处理效率。     

红外光谱Excel处理技术及其应用

红外光谱技术是一种高效、快速的现代分析技术,而Microsoft Excel是一个功能强大的数据处理软件,两者均在很多领域得到了广泛应用。该文利用苯甲酸红外光谱实验数据为操作对象,介绍了用Mi-crosoft Excel软件处理该类型实验数据的详细步骤,包括数据引用方法、图表绘制及其修饰等相关技术。     

Counselors and Client Confidentiality

The school counselors of one state were surveyed about the methods they employed in releasing pupil personnel information to requesting sources. Results indicated that while the methods used to release such data varied by type of information and requesting agency, complete confidentiality was rarely, if ever, extended to school-age clients. Information concerning the educational progress and vocational development of the client was most readily shared with others. While most requested information was released in some form, other school personnel were most likely to receive unabridged data.     

Navajo child abuse and neglect study: A comparison group examination of abuse and neglect of navajo children

The presence of vastly different cultural influences on child rearing and family life in Native Americans than are found in the general population offers an opportunity to examine the issue of child abuse and neglect in a different cultural context. A study was conducted to obtain baseline data and to isolate types and circumstances associated with maltreatment of Navajo children under 9 years of age. Records from tribal and state courts, the Bureau of Indian Affairs (BIA), state social services and a sample of ambulatory pediatric cases were reviewed to elicit abuse or neglect status data for calendar year 1975. Data on 365 abuse or neglect cases were compared with 867 nonabused or nonneglected children (comparison group). A double blind case numbering system was employed to ensure confidentiality of data obtained. Abuse cases were dichotomized according to litigation status (e.g., adjudicated versus documented by clinical findings). Neglect cases were categorized by perceived parental control over circumstances leading to the neglect (e.g., voluntary versus involuntary neglect). Reliability sub-studies were conducted by study staff and Navajo volunteers to assess the degree of agreement in the classification of study case status. Tribal census data for 1975 provided baseline information from which the incidence of abuse or neglect involving Navajo children was established. Extrapolated study data suggests up to 8.6% of the reservation resident Navajo children under age 9 to have been abused or neglected. Various sociode-mographic characteristics differentiating the abusive and neglectful families from those of the nonabused or nonneglected children in the comparison group are reported.     

School Effects Indices: Stability of One- and Two-Level Formulations

Three residual-based methods for indexing school effectiveness were compared using data from elementary schools in Maryland. Two of the methods were regression-based procedures at the school level, and 1 was a hierarchical linear model approach, with Level 1 at the student level and Level 2 at the school level. The 2 methods were applied to a data source in which schools were evaluated separately at Grades 3 and 5 using 3 forms of a statewide performance assessment that were administered to randomly formed groups within each school. The hierarchical linear model approach had higher stability across test forms, but the stabilities of the 1-level formulations were almost as high. The authors concluded that 1-level approaches are viable alternatives when the added data necessary for the hierarchical linear model approach are unavailable.