The purpose of this study is to make out teaching-learning method for developing mathematical abilities of the 1st grade children in elementary school by investigating cognitive effects which mathematical pre-experiences given intentionally by teachers have on children's learning mathematics. The research questions for this purpose are as follows: In learning effects through mathematical pre-experiences given intentionally by teachers. 1) is there any differences between children with pre-experiences and children without them in Mathematics Achievement Test\ulcorner 2) is there any differences between children with pre-experiences and children without them in Transfer Test for learning effects\ulcorner For this study, a class with 41 children in H elementary school located in a Myon near Chong-ju was selected as an experimental group and a class with 43 children in G elementary school in the same Myon was selected as a control group. Nonequivalent Control Group Design of Quasi-Experimental Design was applied to this study. To give pre-experiences to the children in experimental group, their classroom was equipped with materials for pre-experiences, so children could always observe the materials and play with them. The materials were a round-clock on the wall, two pairs of scales, fifty dice, some small pebbles, two pairs of weight scales, two rulers on the wall, and various cards for playing games. Pre-experiences were given to the children repeatedly through games and observations during free time in the morning (00:20-09:00) and intervals between periods. There was a pretest for homogeneity of mathematics achievement between the two groups and were Mathematics Achievement Test (30 items) and Transfer Test (25 items) for learning effects as post-tests. The data were collected from the pretest on April 8 (control group), on April 11 (experimental group) and from the Mathematics Achievement Test and Transfer Test on July 15 (experimental group) and on July 16 (control group). T-test was used to analyze if there were any differences in the results of the test. The results of the analysis were as follows: (1) As the result of pretest, there was not a significance difference between the experimental group (M=17.10. SD=7.465) and the control group (M=16.31, SD=6.974) at p<.05 (p=0.632). (2) For the question 1. in the Mathematics Achievement Test, there was a significant difference between the experimental group (M=26.08, SD=4.827) and the control group (M=22.28. SD=5.913) at p<.01 (p=.003). (3) For the question 2. in the Transfer Test for learning effects. there was a significant difference between the experimental group (M=16.41, SD=5.800) and the control group (M=11.84, SD=4.815) at p<001, (p=.000). From the results of the analyses obtained in this study. the following conclusions can be drawn: First, mathematical pre-experiences given by teachers are effective in increasing mathematical achievement and transfer in learning mathematics. Second, games. observations, and experiments given intentionally by teachers can make children's mathematical experiences rich and various, and are effective in adjusting individual differences for the mathematical experiences obtained before they entered elementary schools. Third, it is necessary for teachers to give mathematical pre-experiences with close attention in order to stimulate children's mathematical interests and intellectual curiosity.

The primary purpose of the present study is to provide the sources to improve the mathematical problem solving performance by analyzing the effects of the belief systems and the misconceptions of the middle school students in solving the problems. To attain the purpose of this study, the reserch is designed to find out the belief systems of the middle school students in solving the mathematical problems, to analyze the effects of the belief systems and the attitude on the process of the problem solving, and to identify the misconceptions which are observed in the problem solving. The sample of 295 students (boys 145, girls 150) was drawn out of 9th grade students from three middle schools selected in the Kangdong district of Seoul. Three kinds of tests were administered in the present study: the tests to investigate (1) the belief systems, (2) the mathematical problem solving performance, and (3) the attitude in solving mathematical problems. The frequencies of each of the test items on belief systems and attitude, and the scores on the problem solving performance test were collected for statistical analyses. The protocals written by all subjects on the paper sheets to investigate the misconceptions were analyzed. The statistical analysis has been tabulated on the scale of 100. On the analysis of written protocals, misconception patterns has been identified. The conclusions drawn from the results obtained in the present study are as follows; First, the belief systems in solving problems is splited almost equally, 52.95% students with the belief vs 47.05% students with lack of the belief in their efforts to tackle the problems. Almost half of them lose their belief in solving the problems as soon as they given. Therefore, it is suggested that they should be motivated with the mathematical problems derived from the daily life which drew their interests, and the individual difference should be taken into account in teaching mathematical problem solving. Second. the students who readily approach the problems are full of confidence. About 56% students of all subjects told that they enjoyed them and studied hard, while about 26% students answered that they studied bard because of the importance of the mathematics. In total, 81.5% students built their confidence by studying hard. Meanwhile, the students who are poor in mathematics are lack of belief. Among are the students accounting for 59.4% who didn't remember how to solve the problems and 21.4% lost their interest in mathematics because of lack of belief. Consequently, the internal factor accounts for 80.8%. Thus, this suggests both of the cognitive and the affective objectives should be emphasized to help them build the belief on mathematical problem solving. Third, the effects of the belief systems in problem solving ability show that the students with high belief demonstrate higher ability despite the lack of the memory of the problem solving than the students who depend upon their memory. This suggests that we develop the mathematical problems which require the diverse problem solving strategies rather than depend upon the simple memory. Fourth, the analysis of the misconceptions shows that the students tend to depend upon the formula or technical computation rather than to approach the problems with efforts to fully understand them This tendency was generally observed in the processes of the problem solving. In conclusion, the students should be taught to clearly understand the mathematical concepts and the problems requiring the diverse strategies should be developed to improve the mathematical abilities.

FEM(Finite Element Method)의 pointwise convergence는 mesh size와 허용오차와의 관계를 분석해 보려는 것이다. 이들 상호 관계에 관한 연구는 FEM에 의한 근사식의 질을 높이는데 중요한 계기가 되어 결과 예측을 하는데 효과적이다. 본 논문은 1-irregular mesh를 이용한 세분화(refinement)로 미지점(unknon node)dlm 수를 최소화 하면서 원하는 점에서의 수렴성을 비교 분석하였다.

The problem of estimating a smooth distribution function F at a point $\tau$ based on randomly right censored data is treated under certain smoothness conditions on F . The asymptotic performance of a certain class of kernel estimators is compared to that of the Kap lan-Meier estimator of F($\tau$). It is shown that the .elative deficiency of the Kaplan-Meier estimate. of F($\tau$) with respect to the appropriately chosen kernel type estimate. tends to infinity as the sample size n increases to infinity. Strong uniform consistency and the weak convergence of the normalized process are also proved.

In this paper, some properties of p-injective ring is studied: The Jacobson radical of a pinjective ring which satisfies the ascending chain condition on essential left ideals is nilpotent. Also, the left singular ideal of a ring which satisfies the ascending chain condition on essential left ideals is nilpotent. Finally, we give an example which shows that a semiprime left p-injective ring such that every essential left ideal is two-sided is not necessarily to be strongly regular.egular.