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1.
Yeping Li  Chunxia Qi 《ZDM》2011,43(6-7):833-845
Online study collaboration is a recent professional development approach that goes beyond school and regional boundaries and even helps reach rural schools in China. In this study, we focused on a specific online study collaboration program to examine its potential benefits for improving participating teachers’ expertise in instructional design. Data were collected from the online study collaboration organizers and four main participating schools. The results reveal the program’s well-structured process and organization for planning and conducting the online study collaboration. Participating teachers benefited from their sharing and discussions with experts and other teachers. Their instructional designs show many important changes that are aligned with experts’ comments. Selected teachers’ expertise improvement includes their knowledge about the textbook and content, their perspectives about students’ learning and instruction, and their learning of different instructional approaches to engage students in classroom instruction. The use of online study collaboration for improving teachers’ expertise and the study’s limitations are then discussed.  相似文献   

2.
In this paper we deal with the problem of assigning teachers to courses in a secondary school. The problem appears when a timetable is to be built and the teaching assignments are not fixed. We have developed a tabu search algorithm to solve the problem. The parameters involved in the algorithm have been estimated by using multiple regression techniques. The computational results, obtained on a set of Spanish secondary schools, show that the solutions obtained by this automatic procedure can be favourably compared with the solutions proposed by the experts.  相似文献   

3.
We study the problem of model predictive control (MPC) for the fish schooling model proposed by Gautrais et al. (2008). The high nonlinearity of the model attributed to its attraction/alignment/repulsion law suggests the need to use MPC for controlling the fish schooling’s motion. However, for large schools, the hybrid nature of the law can make it numerically demanding to perform finite-horizon optimizations in MPC. Therefore, this paper proposes reducing the fish schooling model for numerically efficient MPC; the reduction is based on using the weighted average of the directions of individual fish in the school. We analytically show how using the normalized eigenvector centrality of the alignment-interaction network can yield a better reduction by comparing reduction errors. We confirm this finding on the weight and numerical efficiency of the MPC with the reduced-order model by numerical simulations. The proposed reduction allows us to control a school with up to 500 individuals. Further, we confirm that reduction with the normalized eigenvector centrality allows us to improve the control accuracy by factor of five when compared to that using constant weights.  相似文献   

4.
A new algorithm for aligning text with speech audio signals having lengths of up to several hours is proposed. The algorithm allows its quality to be effectively evaluated. The requirements on the acoustic model are not very demanding. The algorithm can be used to design an audio–video course for learning the Russian language.  相似文献   

5.
Second-grade students in three schools were individually tested on multidigit addition and subtraction problems and solution procedures observed. The schools were all using a reform mathematics curriculum (UCSMP) with an emphasis on problem solving in broader mathematical contexts. Both contextualized and bare computation problems were included in these interviews. On all but one problem, more students used a mental procedure than used the standard written algorithms, and both methods were used with about the same degree of accuracy. Although the standard school algorithm was the only written algorithm used, a number of different mental procedures were employed by students, and choice appeared to be influenced by characteristics of the problems (magnitude of the numbers or the need for regrouping). Major differences between the three schools were found, which are linked to instruction.  相似文献   

6.
THEDESIGNANDANALYSISOFALGORITHMOFMINIMUMCOSTSPANNINGTREE¥(徐绪松,刘大成,吴丽华)XuXusong;LiuDacheng;WuLihua(SchoolofManagement,WuhanUni...  相似文献   

7.
针对大群体应急决策专家之间信任关系及其传递引发的决策风险,以及由于大群体中个体偏好差异较大导致生成独立聚集等问题。首先,提出一个“信任—知识模型”对决策专家之间的信任关系进行集成和传递,并根据决策专家的信任风险偏好得出决策专家之间的信任知识度网络;其次,利用Louvain算法对信任知识度网络进行聚类,高效快速的获得若干个聚集,并用社会网络分析技术确定每个决策者和聚集的权重;然后对每个聚集中的决策者偏好进行集结,并综合决策者给出的信息对备选决策方案进行排序。最后,通过案例分析和对比验证了所提方法的合理性与有效性。  相似文献   

8.
An adaptive algorithm based on computational intelligence techniques is designed, developed and applied to the timetabling problem of educational organizations. The proposed genetic algorithm is used in order to create feasible and efficient timetables for high schools in Greece. In order to demonstrate the efficiency of the proposed genetic algorithm, exhaustive experiments with real-world input data coming from many different high schools in the city of Patras have been conducted. As well as that, in order to demonstrate the superior performance of the proposed algorithm, we compare its experimental results with the results obtained by another effective algorithm applied to the same problem. Simulation results showed that the proposed algorithm outperforms other existing attempts. However, the most significant contribution of the paper is that the proposed algorithm allows for criteria adaptation, thus producing different timetables for different constraints priorities. So, the proposed approach, due to its inherent adaptive capabilities, can be used, each time satisfying different specific constraints, in order to lead to different timetables, thus meeting the different needs that each school may have.  相似文献   

9.
We compare the two most widely known planarity testing algorithms, the one due to Hoperoft and Tarjan, and the other to Lempel. Even, and Cederbaum. These two algorithms are generally viewed as very different approaches to the problems of planarity testing and graph embedding. In this paper, however, by utilizing previously unnoticed freedoms of choice in the order in which the operations of the Hoperoft-Tarjan algorithm can be performed, we create a variation of this algorithm which, in terms of the order in which vertices are processed, is indistinguishable on all planar graph inputs from the Lempel -Even-Cederbaum algorithm. This allows one to create hybridized algorithms which, when interpreted as embedding algorithms, combine all of the features of both procedures.  相似文献   

10.
In school choice, there are two types of extensively used affirmative action policies based on majority quotas and minority reserves, respectively. This paper investigates the responsiveness of the top trading cycles school choice mechanism to these two types of affirmative action policies when all schools have the same priority order over students. Under the common school priority (within student type) condition, we show that the top trading cycles mechanism is minimally responsive to the minority reserves type of affirmative action policy, while a stronger majority quotas type of affirmative action policy may yield a Pareto inferior assignment for the minority.  相似文献   

11.
Summary Constructing a timetable is a difficult problem faced by every school every year. A feasible solution has to satisfy many different requirements and constraints. A good solution has to provide compact timetables for classes and teachers. In order to help the schools, we have developed HORES, a robust and flexible timetabling system suited to the needs of Spanish secondary schools. HORES runs on a PC and is fast and user-friendly. It may handle virtually every condition required by the schools and obtains good quality solutions in very short computing times. It also allows the user to modify interactively the solutions. HORES is now being used by schools with satisfactory results.  相似文献   

12.
This paper proposes a new interpretation of intervals as classes of functions having the same domain. Interval operations are seen as operations on these classes. This approach allows to recover Markov's directed interval arithmetic by taking into account the monotonicity of the functions.  相似文献   

13.
Mathematical morphology started as a set of tools for analysing images by the use of transformations based on set-theoretical operations which are the Minkowski sum and subtraction. It was first developed for the analysis of binary images. Its extension to grey-level images was a later development with the extension of the Minkowski operations to real-valued functions in terms of sup-convolution and inf-convolution. The purpose of this paper is to define a type of convolution between set-valued maps, to study its properties, and to establish some associated differential relations. This set-convolution map allows us to extend the Minkowski sum and substraction to multivalued functions and to functions with vectorial values.  相似文献   

14.
The purpose of this paper is to compare the efficiency of a set of Spanish public and private high schools using data envelopment analysis (hereafter DEA). In view of the usual difficulties of obtaining reliable budget figures on private schools, we have used a restrictive efficiency notion which focuses on the relation between the academic results obtained by each school and the socio-economic background and academic profile of its pupils. In this study, special emphasis is placed upon decomposing the overall inefficiencies of each school into managerial (due to individual performance) and programme (due to structural differences between management models) components. Our results reveal that although, in general, private schools obtain better academic results than public schools in absolute terms, this is not the consequence of comparatively more effective management but rather of having pupils with a more favourable background for the educational process.  相似文献   

15.
The main purpose of this paper is to make available an algorithm to perform Boolean set operations on nonconvex polygons. Along the way the representation of polygons by oriented boundaries and vertex sets is discussed. It is found that the logical core of the method is simple due to a topological steering criterion that applies equally to all Boolean operations. The computational provisions are briefly explained, and an example and an application end the paper. There are three figures and an Appendix with APL codes.  相似文献   

16.
We have recently discussed the performance of local second-order two-dimensional absorbing boundary conditions of elliptical shape for scattering and radiation problems involving sound-hard obstacles embedded in a full-plane. In this article, using the method of images, we extend the applicability of elliptically shaped truncation boundaries to semi-infinite acoustic media. For problems in either the time- or the frequency-domains, involving near-surface structures of elongated cross-sections, we show that significant computational savings are attainable when compared against semi-circular truncation geometries.  相似文献   

17.
Within the educational context, a key goal is to assess students’ acquired skills and to cluster students according to their ability level. In this regard, a relevant element to be accounted for is the possible effect of the school students come from. For this aim, we provide a methodological tool which takes into account the multilevel structure of the data (i.e., students in schools) and allows us to cluster both students and schools into homogeneous classes of ability and effectiveness, and to assess the effect of certain students’ and school characteristics on the probability to belong to such classes. The proposed approach relies on an extended class of multidimensional latent class IRT models characterised by: (i) latent traits defined at student and school level, (ii) latent traits represented through random vectors with a discrete distribution, (iii) the inclusion of covariates at student and school level, and (iv) a two-parameter logistic parametrisation for the conditional probability of a correct response given the ability. The approach is applied for the analysis of data collected by two national tests administered in Italy to middle school students in June 2009: the INVALSI Language Test and the Mathematics Test.  相似文献   

18.
Between 1965 and 1976 the number of children born in the UK decreased by about one third. The fall in the number of births was followed by a fall in the number of children on roll in compulsory education, which resulted in many schools being closed. This paper examines the dynamics of falling rolls in the city of Southampton. Multidimensional scaling techniques are used to explore the social characteristics of the schools proposed for closure. The paper examines also the consequences of the exercise of parental choice of school. It is shown that social dynamics and staffing rules based on constant pupil/teacher ratios remove resources from the schools that are most in need of them.  相似文献   

19.
A Parameter Selection Method for Wavelet Shrinkage Denoising   总被引:1,自引:0,他引:1  
Thresholding estimators in an orthonormal wavelet basis are well established tools for Gaussian noise removal. However, the universal threshold choice, suggested by Donoho and Johnstone, sometimes leads to over-smoothed approximations.For the denoising problem this paper uses the deterministic approach proposed by Chambolle et al., which handles it as a variational problem, whose solution can be formulated in terms of wavelet shrinkage. This allows us to use wavelet shrinkage successfully for more general denoising problems and to propose a new criterion for the choice of the shrinkage parameter, which we call H-curve criterion. It is based on the plot, for different parameter values, of the B 1 1(L 1)-norm of the computed solution versus the L 2-norm of the residual, considered in logarithmic scale. Extensive numerical experimentation shows that this new choice of shrinkage parameter yields good results both for Gaussian and other kinds of noise.  相似文献   

20.
Solving a school bus scheduling problem with integer programming   总被引:1,自引:0,他引:1  
In many rural areas in Germany pupils on the way to school are a large if not the largest group of customers in public transport. If all schools start more or less at the same time then the bus companies need a high number of vehicles to serve the customer peak in the morning rush hours. In this article, we present an integer programming model for the integrated coordination of the school starting times and the public bus services. We discuss preprocessing techniques, model reformulations, and cutting planes that can be incorporated into a branch-and-cut algorithm. Computational results show that in our test counties a much lower number of buses would be sufficient if the schools start at different times.  相似文献   

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