DISTRIBUTIVE PARTITIONING OPERATION IN MATHEMATICAL SITUATIONS INVOLVING FRACTIONAL QUANTITIES

In the present study, we describe a participating student’s (Carol’s) distributive partitioning scheme and operations along with Steffe’s and his colleagues’ studies about children’s constructions of fraction knowledge as a particular model of mathematical learning. Analysis of Carol’s mathematical behaviors indicates that an operationally common mathematical behavior (distributive partitioning operation) was revealed in various mathematical problem situations such as fraction multiplication, fraction division, and multiplicative transformation between fractional quantities. It both provides a rationale for why becoming versed in one mathematical subject could facilitate working with another mathematical subject and also implies the necessity of describing and defining students’ mathematical behaviors from an operational view of knowledge, which might lead to building foundations of a substantial cognitive map for students’ mathematical development.     

Knowledge production in a constructed field: reflections on comparative and international education

Adopting Maria Manzon’s theoretical framework, which draws on Foucault and proposes that comparative education as an academic field is socially constructed, I suggest that the field is neither stable nor well defined. To demonstrate this, I conduct a content analysis of the Comparative Education Review, using Klaus Krippendorff’s methodological framework to study comparative and international education (CIE) researchers’ understanding of the national—and of their related knowledge production in the field. Many comparativists express interests in multiple countries, and their knowledge production takes the form of individual country studies. The countries are habitually studied using a “problem approach” focusing on one specific aspect of the country under investigation and using an associated social science methodology deemed appropriate. Few comparativists are making explicit use of or reference to any methodology that is unique to comparative education. Efforts to catalog and systematize CIE research have demonstrated that the field is becoming so inclusive that it hardly is distinguishable from educational studies as a whole. Hence, I suggest that instead of speaking about unifying features of the field, it may be more relevant to speak about frequent elements, such as a focus on the national, and a knowledge production characterized by the academic practitioner who desires to improve the education systems studied. A third frequent element may be the focus on educational development, thus justifying the label of “comparative, international, and development education.” One challenge of the field is its dependence on Western social science discourses, which may be marginalizing other voices.     

Students’ Motivation in the Mathematics Classroom. Revealing Causes and Consequences

Students’ affective domain has been popular in the mathematics education community in an ongoing attempt to understand students’ learning behavior. Specifically, enhancing students’ motivation in the mathematics classroom is an important issue for teachers and researchers, due to its relation to students’ behavior and achievement. This paper utilized achievement goal theory—an important theoretical prospect on students’ motivation in school settings—to investigate the existence of a model presenting the relation between motivation and other affective constructs and students’ performance in mathematics. In this regard, two types of tests were administered to 321 sixth grade students measuring their motivation and other affective constructs and their performance in mathematics. Using structural equation modeling, we examined the associations among the affective constructs, motivation, and the extent to which these constructs influence students’ performance and interest in mathematics. The data revealed that students’ performance and their interest in mathematics were influenced by fear of failure, self-efficacy beliefs, and achievement goals. We discuss these findings in terms of teaching implications in the mathematics classroom.     

基于MATLAB的Huffman编码实验教学平台设计

针对Huffman编码实验教学中的有关计算问题,本文利用MATLAB的图形用户界面,设计开发了一个简单实用的实验教学平台。该平台实现了理论和实验相结合,为Huffman编码的实验教学提供了一个有效的工具。     

科研机构名称归一化实现

[目的/意义]机构名称的数目多且较为繁杂,机构名称归一化可将同一机构的规范名称以及不同时段、不同表达形式的非规范名称汇集在一起,提高查询检索的查全率和查准率;有利于建立与其他系统之间的互操作,实现资源的共享。[方法/过程]在分析机构名称字符串的特点和基于K-means算法的基础上,利用编辑距离算法实现一级机构名称的初步聚类,然后利用初步聚类结果并基于TF-IDF算法计算机构名称各词项的权值,从而基于K-means算法将机构名称围绕聚类中心抱团聚簇,并对每一个簇的机构名称赋予唯一标识符。[结果/结论]该方法可实现同一机构实体不同形式的规范名称的归一,提高机构名称聚类的准确率,但对K取值、距离测度方法的选取仍有待优化。     

移动终端上文献管理工具的比较研究

文献管理工具是一种可以有效提高科研工作者学习研究效率的软件,移动终端上的文献管理工具将用户从PC中解脱出来,让用户可以随时随地阅读、管理参考文献.论文选取五款典型的移动终端上的文献管理工具,采用ISO/IEC9126-2000模型,分别从功能性、效率性、易用性、可移植性四个方面进行比较.最后,针对比较结果,指出目前移动终端的文献参考工具具有网络搜索功能薄弱、共享方式少、检索方式单一和书目信息导出方面的功能缺失等不足.     

基于马尔可夫模型的风险型客户预测与管理

客户是企业的重要资产之一,是企业实现利润的源泉。客户关系的发展形成一个完整的生命周期,处于生命周期形成阶段的客户往往要消耗较多的资源却甚少为企业创造价值,企业的投入具有风险性。本文对风险型客户发展过程中的特点进行分析,同时提出基于马尔科夫模型的风险型客户预测方法,掌握风险型客户在市场竞争过程中的市场占有率信息,从而为企业的战略决策提供支持。     

浅析高职“商品学”教学中的问题及对策

商品学是我国高职等院校经济管理类专业的基础课和必修课,本文通过对在教学中面临的诸多问题进行分析,并结合当前环境条件,提出了相关的解决办法。     

Output consensus of heterogeneous linear systems with quantized information

In this paper, we design two distributed output consensus controllers for heterogeneous linear systems based on internal model principle and then study the quantization effect on the controllers when uniform quantizers are used in the communication channels. The first controller considers the general situation when the internal model state matrix of the system may be unstable and the communication graphs are strongly connected directed graphs. We prove that the bound of the consensus error is proportional to the quantizer parameter with a coefficient related to the size of the network and the property of the communication graphs. The second controller considers the situation when the internal model state matrix is neutrally stable and the communication graphs are undirected connected graphs. In this case, we derive a better bound of the consensus error which is proportional to the quantizer parameter and the coefficient is unrelated to the size of the network when the linear systems are homogeneous. Simulation examples are provided to illustrate the theoretical results.     

Generalized matrix projective synchronization of general colored networks with different-dimensional node dynamics

This paper investigates the generalized matrix projective synchronization problem of general colored networks with different-dimensional node dynamics. A general colored network consists of colored nodes and edges, where the dimensions of colored node dynamics can be different in addition to the difference of the inner coupling matrices between any pair of nodes. For synchronizing a colored network onto a desired orbit with respect to the given matrices, open-plus-closed-loop controllers are designed. The closed-loop controllers are chosen as adaptive feedback and intermittent controllers, respectively. Based on the Lyapunov stability theory and mathematical induction, corresponding synchronization criteria are derived. Noticeably, many existing synchronization settings can be regarded as special cases of the present synchronization framework. Numerical simulations are provided to verify the theoretical results.