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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
71

A research study on grade five problem posing-Case of four arithmetical operations

Wu, Jin-biau 27 January 2005 (has links)
The main purpose of this research is to explore the implementation of problem-posing teaching activities for fifth grade students in the elementary school. The teaching material is on mixed operations of addition, subtraction, multiplication and division. The method of posing problems is Tsubota¡¦s ¡§Classified Subject¡¨, adopted from Japan. The teaching of posing problems was divided into two phases; one is ¡§problem solving¡¨, the other is ¡§problem posing then solving¡¨. According to this method, students initially solve the problems that the teacher provided. Second, taking this subject as the foundation, students posed the problems by themselves and solved the problems as well. During this research, the researcher utilized a variety of ways to collect data, such as self-construction of instruments on four arithmetic operations, problem-solving worksheets, problem-posing worksheets, learning diaries, and reflective notes. The goals of this research are four: first, analyzing the categories of students¡¦ work and the contents of posing problems that student created; second, investigating into the performance of problem solving; third, probing students¡¦ opinions of problem-posing activities; four, the difficulties the teacher encountered. The results of this research were four. First, it showed that 98.5% of students given problems included sufficient data for solving. Students virtually were able to make feasible problems. Moreover, the majority of students were capable to, not only changing numerals of the problems, but also changing structures of the problems. The tendency of changing structure followed multiple aspects of developments. Second, students¡¦ performance on three steps operations problem solving was low; the performances of problem solving and problem posing then solving were close; students¡¦ performance at problem posing then solving stage was higher; and, the major reason for mistakes was insufficient procedural knowledge. Third, students expressed a liking of problem posing, they thought that the materials were interesting, and showed promising study manner. Fourth, the teacher encountered problems such as time control, the development of in-class presentation culture, and, few students¡¦ lack of concentration while problem posing.
72

Locus of control, need for cognition, and a hierarchical approach to real-world problem solving : searching for a problem solving personality

Vanhorn, Renee E. January 1994 (has links)
The purpose of this study was to explore the effects of two problem-solving techniques and two personality variables upon the quantity and self-reported quality of solutions people generated to an ill-structured problem. College students completed the Locus of Control and Need for Cognition Scales and, after having been trained in either brainstorming or a hierarchical problem-solving method, they used their new skill to solve a problem. They also rated their solutions on quality. Subjects in the hierarchical condition produced more solutions than those in brainstorming. Moreover, those in the hierarchical group produced solutions of subjectively higher quality than did the brainstormers. Analyses of the personality variables suggested that as need for cognition increased, people generated more solutions before training. No relationship was found between need for cognition and quality ratings. Locus of control was not related to either quantity or quality. Implications for business are discussed and suggestions for future research are provided. / Department of Psychological Science
73

Discrete analogues of Kakeya problems

Iliopoulou, Marina January 2013 (has links)
This thesis investigates two problems that are discrete analogues of two harmonic analytic problems which lie in the heart of research in the field. More specifically, we consider discrete analogues of the maximal Kakeya operator conjecture and of the recently solved endpoint multilinear Kakeya problem, by effectively shrinking the tubes involved in these problems to lines, thus giving rise to the problems of counting joints and multijoints with multiplicities. In fact, we effectively show that, in R3, what we expect to hold due to the maximal Kakeya operator conjecture, as well as what we know in the continuous case due to the endpoint multilinear Kakeya theorem by Guth, still hold in the discrete case. In particular, let L be a collection of L lines in R3 and J the set of joints formed by L, that is, the set of points each of which lies in at least three non-coplanar lines of L. It is known that |J| = O(L3/2) ( first proved by Guth and Katz). For each joint x ∈ J, let the multiplicity N(x) of x be the number of triples of non-coplanar lines through x. We prove here that X x2J N(x)1=2 = O(L3=2); while we also extend this result to real algebraic curves in R3 of uniformly bounded degree, as well as to curves in R3 parametrized by real univariate polynomials of uniformly bounded degree. The multijoints problem is a variant of the joints problem, involving three finite collections of lines in R3; a multijoint formed by them is a point that lies in (at least) three non-coplanar lines, one from each collection. We finally present some results regarding the joints problem in different field settings and higher dimensions.
74

none

Huang, Shih-ting 28 June 2007 (has links)
This paper extends respectively Gale-Shapley¡¦s model and Balinski-Sonmez¡¦s model to analyze the college admission problem and the student placement problem in the case of Taiwan. Given the assumption that time is not considered as a critical dimension of this issue, it is argued that Taiwan¡¦s admission mechanism is in accordance with the criterion of the student optimal stable mechanism with number restriction. As well, the outcome of Taiwan¡¦s admission mechanism exhibits features which are similar to that of the student optimal stable matching with number restriction. However, with regard to Taiwan¡¦s student placement mechanism, it is demonstrated that inefficiency may prevail.
75

The strategies used by ten grade 7 students, working in single-sex dyads, to solve a technological problem

Welch, Malcolm W. (Malcolm William) January 1996 (has links)
The purpose of this study was to investigate the problem-solving strategies of students as they attempted to find a solution to a technological problem. Ten Grade 7 students, who had received no prior technology education instruction, were formed into single-sex dyads and provided with a design brief from which they designed and made a technological solution. The natural talk between the subjects was transcribed. A description of their designing-in-action was added to the transcript. Actions were coded using an empirically derived scheme grounded in both a general problem-solving model and theoretical models of the design process. Segments coded as designing were analyzed using descriptive statistics. This analysis provided the data for mapping, that is, visually representing the design process used by subjects. / Results showed that novice designers do not design in the way described in textbooks. Their strategy is not linear but highly iterative. Subjects developed their ideas using three-dimensional materials rather than two-dimensional sketches. They were unlikely to generate several possible solutions prior to modelling, but developed solutions serially. The act of modelling stimulated the generation of additional ideas. Evaluation occurred repeatedly throughout their designing.
76

Some aspects of three and four-body dynamics

Barkham, Peter George Douglas January 1974 (has links)
Two fundamental problems of celestial mechanics are considered: the stellar or planetary three-body problem and a related form of the restricted four-body problem. Although a number of constraints are imposed, no assumptions are made which could invalidate the final solution. A consistent and rational approach to the analysis of four-body systems has not previously been developed, and an attempt is made here to describe problem evolution in a systematic manner. In the particular three-body problem under consideration two masses, forming a close binary system, orbit a comparatively distant mass. A new literal, periodic solution of this problem is found in terms of a small parameter e, which is related to the distance separating the binary system and the remaining mass, using the two variable expansion procedure. The solution is accurate within a constant error O(e¹¹) and uniformly valid as e tends to zero for time intervals 0(e¹⁴). Two specific examples are chosen to verify the literal solution, one of which relates to the sun-earth-moon configuration of the solar system. The second example applies to a problem of stellar motion where the three masses are in the ratio 20 : 1 : 1. In both cases a comparison of the analytical solution with an equivalent numerically-generated orbit shows .close agreement, with an error below 5 percent for the sun-earth-moon configuration and less than 3 percent for the stellar system. The four-body problem is derived from the three-body case by introducing a particle of negligible mass into the close binary system. Unique uniformly valid solutions are found for motion near both equilateral triangle points of the binary system in terms of the small parameter e, where the primaries move in accordance with the uniformly-valid three-body solution. Accuracy, in this case, is Q maintained within a constant error 0(e⁸), and the solutions are uniformly valid as e tends to zero for time intervals 0(e¹¹). Orbital position errors near L₄ and L₅ of the earth-moon system are found to be less than 5 percent when numerically-generated periodic solutions are used as a standard of comparison. The approach described here should, in general, be useful in the analysis of non-integrable dynamic systems, particularly when it is feasible to decompose the problem into a number of subsidiary cases. / Applied Science, Faculty of / Electrical and Computer Engineering, Department of / Graduate
77

Expert vs. Novice: Problem Decomposition/Recomposition in Engineering Design

Ting, Song 01 May 2014 (has links)
The purpose of this research was to investigate the differences of using problem decomposition and problem recomposition among dyads of engineering experts, dyads of engineering seniors, and dyads of engineering freshmen. Fifty participants took part in this study. Ten were engineering design experts, 20 were engineering seniors, and 20 were engineering freshmen. Participants worked in dyads to complete an engineering design challenge within an hour. The entire design process was video and audio recorded. After the design session, members participated in a group interview. This study used protocol analysis as the methodology. Video and audio data were transcribed, segmented, and coded. Two coding systems including the FBS ontology and “levels of the problem” were used in this study. A series of statistical techniques were used to analyze data. Interview data and participants’ design sketches also worked as supplemental data to help answer the research questions. By analyzing the quantitative and qualitative data, it was found that students used less problem decomposition and problem recomposoition than engineer experts in engineering design. This result implies that engineering education should place more importance on teaching problem decomposition and problem recomposition. Students were found to spend less cognitive effort when considering the problem as a whole and interactions between subsystems than engineer experts. In addition, students were also found to spend more cognitive effort when considering details of subsystems. These results showed that students tended to use dept-first decomposition and experts tended to use breadth-first decomposition in engineering design. The use of Function (F), Behavior (B), and Structure (S) among engineering experts, engineering seniors, and engineering freshmen was compared on three levels. Level 1 represents designers consider the problem as an integral whole, Level 2 represents designers consider interactions between subsystems, and Level 3 represents designers consider details of subsystems. The results showed that students used more S on Level 1 and 3 but they used less F on Level 1 than engineering experts. The results imply that engineering curriculum should improve the teaching of problem definition in engineering design because students need to understand the problem before solving it.
78

The effects of generating inferences about a solution principle on analogical transfer in children and adults.

Yanowitz, Karen L. 01 January 1993 (has links)
No description available.
79

The perception of problem behavior of secondary school students /

Edwards, Dean January 1976 (has links)
No description available.
80

Problem Framing in Problem-Oriented Policing:An Examination of Framing from Problem Definition to Problem Response

Gallagher, Kathleen M. 12 September 2014 (has links)
No description available.

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