• The KIPS Transactions:PartC
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• v.10C no.3
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• pp.367-376
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• 2003

This study deals with the DCMST (Delay constrained Capacitated Minimum Spanning Tree) problem applied in the topological design of local networks or finding several communication paths from root node. While the traditional CMST problem has only the traffic capacity constraint served by a port of root node, the DCMST problem has the additional mean delay constraint of network. The DCMST problem consists of finding a set of spanning trees to link end-nodes to the root node satisfying the traffic requirements at end-nodes and the required mean delay of network. The objective function of problem is to minimize the total link cost. This paper presents two-phased heuristic algorithm, which consists of node exchange, and node shift algorithm based on the trade-off criterions, and mean delay algorithm. Actual computational experience and performance analysis show that the proposed algorithm can produce better solution than the existing algorithm for the CMST problem to consider the mean delay constraint in terms of cost.

• Korean Journal of Social Welfare
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• v.63 no.3
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• pp.83-108
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• 2011

This qualitative study is designated to explore the reality of social welfare related to the co-occurence of domestic violence and child maltreatment in Korea. "Alone and Together" is elicited as the main theme from the analysis of social workers' experiences with the co-occurence problem in the two fields of domestic violence and child maltreatment. Despite the fact that the social workers are aware of the co-occurence problem embedded in their field cases, they don't assess and intervene with the problem on set purpose. Each field has dealt with the problem according to the field priority for either women or children separately. However, the social workers in the both fields desire alternatives effective for their cooperation and linkage to each other when confronted with the intersection of interdependent needs and problem-solving for the woman and the child. The development of multi-level research, assessment tools, and compulsory education courses for practitioners related to the co-occurence problem is suggested.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.48 no.2
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• pp.6-13
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• 2011

This paper deals with the interconnection problem in ad-hoc networks or sensor networks, where relay nodes are deployed additionally to form connections between given nodes. This problem can be reduced to a NP-hard problem. The nodes of the networks, by applications or geographic factors, can be deployed densely in some areas while sparsely in others. For such a case one can make an approximation scheme, which gives shorter execution time, for the additional node deployments by ignoring the interconnections inside the dense area of nodes. However, the case is still a NP-hard, so it is proper to establish a polynomial time approximation scheme (PTAS) by implementing a dynamic programming. The analysis can be made possible by an elaboration on making the definition of the objective function. The objective function should be defined to be able to deal with the requirement incurred by the substitution of the dense area with its abstraction.

• The Journal of the Korea institute of electronic communication sciences
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• v.10 no.10
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• pp.1197-1204
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• 2015

In this study, 8th Korea Welfare Panel data surveys utilizing 65 years age or older, problem drinking analyzed the impact on suicidal thoughts as a medium for depression and self-esteem. In the main analysis, First, Problem drinking appears to influence the level of statistically significant positive (+) of suicidal thoughts. Second, Depression was found to mediate the relationship between the full level of problem drinking and suicidal thoughts. Third, Problem drinking was found not appear to be significant influence on self-esteem is not the mediating effect of self-esteem. However, the higher level of problem drinking, the lower level of self-esteem, through the sign of regression coefficient is negative (-) potential of the relationship was confirmed. These results suggest that more systematic research is necessary for the elderly suicide with preparing for the elderly of problem drinking.

• Journal of the Korean School Mathematics Society
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• v.13 no.3
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• pp.381-395
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• 2010

The purpose of this paper is to examine the competence and the methods of problem solving in four operations word problems based on the informal knowledges by five-year-old children. The numbers which are contained in problems consist of the numbers bigger than 5 and smaller than 10. The subjects were 21 five-year-old children who didn't learn four operations. The interview with observation was used in this research. Researcher gave the various materials to children and permitted to use them for problem solving. And researcher read the word problems to children and children solved the problems. The results are as follows: five-year-old children have the competence of problem solving in four operations word problems. They used mental computation or counting all materials strategy in addition problem. The methods of problem solving were similar to that of addition in subtraction, multiplication and division, but the rate of success was different. Children performed poor1y in division word problems. According to this research, we know that kindergarten educators should be interested in children's informal knowledges of four operations including shapes, patterns, statistics and probability. For this, it is needed to developed the curriculum and programs for informal mathematical experiences.

• Journal of the Korean School Mathematics Society
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• v.15 no.3
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• pp.511-533
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• 2012

In order to determine whether there is a significant correlation between relational understanding and creative math. problem finding ability, this study performed relational understanding and problem finding ability tests on a sample of 186 8th grade middle school students. According to the study results, we found a very significant positive correlation between relational understanding and the creativity of the mathematising ability and the combining ability of mathematical concepts in the problem finding ability. Although there was no statistically significant correlation between relational understanding and the extension ability of mathematical facts, the results from analyzing the students response rate and actual scores in each test showed that students with high relational understanding scores also had high response rate and high scores in analogical reasoning and inductive reasoning. Through this study, therefore, relational understanding is found to have a positive impact on the creative mathematics problem finding ability.

• Journal of Korean society of Dental Hygiene
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• v.14 no.5
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• pp.667-672
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• 2014

Objectives : The purpose of this study was to examine classifying the level and accuracy of the meta-cognitive level of students and dental hygiene, and to understand the impact on the process of problem solving and accordingly, it is intended to provide a basis for learning strategies. Methods : A self-reported questionnaire was filled out by 328 dental hygiene students in 3 colleges in Gyeonggi-do and Chungnam. Data were analyzed by the frequency analysis, one-way ANOVA, Scheffe's post-hoc test, Pearson's correlation coefficient using SPSS 12.0. Results : Meta-cognitive level of the subject was on average 4.43 points and problem solving level was lower at 2.82 points. Showed a significant difference in satisfaction with the major motives meta-cognitive level in accordance with the general characteristics of the subjects(p<0.05). Results of this study showed that no statistically significant differences in both the sub-areas of the level of problem solving according to the general characteristics of the subject(p>0.05). There was no correlation between the ability to solve problems and meta-cognitive level of the subjects(p>0.05). Conclusions : The finding of the study showed that meta-perception of dental hygiene students are lower the level of problem-solving that is compared to meta-cognition. It is suggested that development of a variety of learning methods for improving meta-cognitive thinking and problem-solving skills required in dental hygiene school curriculum.

• Journal of Engineering Education Research
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• v.12 no.4
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• pp.30-37
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• 2009

The purpose of this study was to examine the difference of problem-solving ability according to student's level of self-efficacy. Participants were 72 junior students who took the course 'Environmental Instrumental Analysis'. Before the PBL activities, students were given the self-efficacy tests to all students. Among them, 44 students(30% of each high and low ranking) were selected and encouraged to complete pre-problem solving tests. The PBL was conducted for 12 weeks using blended learning strategies. After the PBL, 44students completed post-problem solving tests. Results showed that there were differences of problem-solving ability according to student's level of self-efficacy. From the results, instructional strategies for promoting students' self-efficacy should be employed for enhancing problem-solving ability in PBL activities.

• Journal of The Korean Association For Science Education
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• v.8 no.1
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• pp.43-55
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• 1988

This study intended to find the differences between expert's and novice's thinking processes when they solve physics problems. Five physics professors and twenty sophomore students in a physics department were participated in the study. The researcher investigated their thinking processes in solving three physics problems on NEWTON's law of motion. The researcher accepted so called "Thinking Aloud" method. The thinking processes were recorded and transfered into protocols. The protocols were analysised by problem solving process coding system which was developed by the researcher on the basis of Larkin's problem solving process model. The results were as follows: (1) There was no difference of time required in solving physics problem of low difficulty between expert and novices; but, it takes 1.5 times longer for novices than experts in solving physics problems which difficulties are high and average. (2) Novices used working forward strategy and working backward strategy at the similiar rate in solving physics problems which difficulties were average and low. while Novices mo mostly used working backward strategy in solving physic problems which difficulty was high. Experts mostly used working forward strategy in solving physics problems whose difficulties was average and low, however experts used working forward strategy and working backward strategy at the similiar rate in solving physics problem which difficulty was high. (3) Novices usually wrote only a few information on the diagram of figure they drawn, on the other hand experts usually wrote almost all the information which are necessary for solving the problems. (4) Experts spent much time in understand the problem and evaluation stage than novices did, however experts spent less time in plan stage than novices did. (5) Physics problems are solved in sequence of understanding the problem, plan, carrying out the plan, and evaluation steps regardless of problem difficulty.

• Journal of Digital Convergence
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• v.16 no.2
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• pp.225-234
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• 2018

The purpose of this study was to examine relationships among drinking motives, acculturative stress and problem drinking, and then to identify the influencing factors of problem drinking in foreign workers. A total of 120 foreign workers recruited from two shipyards in G city. Self-reported questionnaire survey was conducted from October to December, 2016. As a result, a rate of problem drinking in foreign workers was 39.2%. According to the multiple regression analysis, their problem drinking was significantly influenced by social motives (${\beta}=.368$ p=.003) and conformity motives (${\beta}=.337$ p=.005) as a subscale of drinking motives and homesickness (${\beta}=-.197$, p=.009) as a subscale of acculturative stress, explained 39.5% of the total variance (F=26.849, p=.000). Based on our results, an education program using drinking motives, acculturative stress should be developed to prevent problem drinking in foreign workers.