• The Journal of the Korea Contents Association
• /
• 제14권10호
• /
• pp.619-627
• /
• 2014

The purpose of this study is to investigate the levels of depression of the college students, and correlation of depression and anxiety, unemployment stress, self-esteem, and finally to explore the moderating effect of resilience between those variables. The participants of the survey were 298 college students. The data were analyzed with t-test, ANOVA test, Pearson correlation coefficient, and moderated multiple regression by SPSS Win 18.0. The major findings were as follow; students appear to have more depression when they are female, in 1st, 2nd, 4th grades than 3rd grade, and in a low economical status. Students' depression had a positive correlation with anxiety and unemployment stress, and had a negative correlation with self-esteem, resilience. In moderated multiple regression analysis, self-esteem and anxiety were influenced by resilience such as self-control ability. Therefore, the intervention strategies for decreasing depression of college students should include development of resilience, especially self-control ability in specific, besides control of the anxiety and unemployment stress.

• Reproductive and Developmental Biology
• /
• 제29권2호
• /
• pp.93-99
• /
• 2005

Human embryonic stem cells (hESCs) derived from the inner cell mass of blastocysts have the ability to renew themselves and to differentiate into cell types of all lineage. The present study was carried out to investigate whether the Wnt signaling pathway is related to maintaining self-renewal of hESCs. Glycogen Synthase Kinase 3 (GSK-3) inhibitor, BIO ((2'Z,3'E)-6-Bromoindirubin-3'-oxime) was treated to Miz-hES1 line for activation of Wnt signaling pathway. BIO-nontreated hESCs (control) and BID-treated hESCs were cultured for 5 days in the modified feeder-free system. During the culture of hESCs, differences were observed in the colony morphology between 2 groups. Controls were spread outwards whereas BIO-nontreated hESCs were clumped in the center and the differentiated cells were spreading outwards in the edges. The results of stem cell specific marker staining indicated that control were differentiated in large part whereas BIO-treated hESCs maintain self-renewal in the center of the colony. The results of lineage marker staining suggested that outer cells of the hESC colony were differentiated to the neuronal progenitor cells in both control and BIO-treated hESC. These results indicate that Wnt signaling is related to self-renewal in hESCs. In addition, control group showed higher composition of apoptotic cells $(23.76\%)$ than the BID-treated group $(5.59\%)$. These results indicate that BIO is effective on antapoptosis of hESCs.

• International Journal of Control, Automation, and Systems
• /
• 제4권6호
• /
• pp.756-762
• /
• 2006

Shape Memory Alloy(SMA) actuators, which have the ability to return to a predetermined shape when heated, have many potential applications such as aeronautics, surgical tools, robotics and so on. Although the conventional PID controller can be used with slow response systems, there has been limited success in precise motion control of SMA actuators, since the systems are disturbed by unknown factors beside their inherent nonlinear hysteresis and changes in the surrounding environment of the systems. This paper presents a new development of a SMA position control system by using a self-tuning fuzzy PID controller. This control algorithm is used by tuning the parameters of the PID controller thereby integrating fuzzy inference and producing a fuzzy adaptive PID controller, which can then be used to improve the control performance of nonlinear systems. The experimental results of position control of SMA actuators using conventional and self-tuning fuzzy PID controllers are both included in this paper.

• 제어로봇시스템학회:학술대회논문집
• /
• 제어로봇시스템학회 1997년도 한국자동제어학술회의논문집; 한국전력공사 서울연수원; 17-18 Oct. 1997
• /
• pp.704-707
• /
• 1997

In this paper, we present a fuzzy logic based tuner for continuous on-line tuning of PID controllers. The essential idea of the scheme is to parameterize a Ziegler-Nichols-like tuning formula by a singler parameter .alpha., then to use an on line fuzzy logic to self-tune the parameter. The adaptive scaling makes the controller robust against large variations in parametric and dynamics uncertainties in the plant model. New self-tuning controller has the ability to decide when to use PI or PID control by extracting process dynamics from relay experiments. These scheme lead to improved performance of the transient and steady state behavior of the closed loop system, including processes with nonminimum phase processes.

• Journal of Engineering Education Research
• /
• 제23권1호
• /
• pp.37-46
• /
• 2020

The purpose of this study is to develop the self-reported measurement for engineering design competency. In this study, engineering design competency is defined as the overall individual ability that is necessary for an engineer for his/her successful accomplishment of engineering design. This measurement was developed through reviewing documents, defining factor and sub-factor, making an item and constructing validity verification. The self-reported measurement for engineering design competency consists of 6 factors and 40 items. 6 factors cover competency of design performance, competency of considering economic and social influence, competency of utilizing mathematical and scientific knowledge, competency of teamwork, competency of design-centered thinking and competency of collecting and using data. A 6-points Likert scale was used for each item.

• International Journal of Advanced Culture Technology
• /
• 제9권1호
• /
• pp.168-176
• /
• 2021

This study developed and evaluated a learning model to improve collaborative problem-solving skills for nursing students taking physiology courses. This one-group pretest-posttest design used the jigsaw cooperative learning method on 30 nursing students from one local university. We analyzed the effect of a cooperative problem- solving learning model using SPSS 21.0 to compare changes in the students' collaborative self-efficacy, problem-solving abilities, and team-member exchange. As a result, the participants showed significant increases in collaborative self-efficacy, problem-solving ability, and team-member exchange after experiencing cooperative problem- solving learning model. Therefore, we will help nursing students improve their communication skills by enhancing their collaborative self-efficacy and help them solve problems effectively in conflict situations.

• Journal of Korean Academy of Nursing
• /
• 제50권1호
• /
• pp.116-131
• /
• 2020

Purpose: This study aimed to develop a smartphone overdependence prevention program for college students based on the self-determination theory (SDT) and evaluate its effectiveness. Methods: A non-equivalent control group repeated measures design was used for the study. Participants were 64 university freshmen (experimental group: 29, control group: 35). The developed program consists of eight sessions conducted twice a week. The program was designed to promote autonomy, competence, and relatedness the three elements of the basic psychological needs of self-determination theory. The participants were assessed before the program, immediately after, and 1 and 3 months after the program. Data were collected from April 23 to September 14, 2018 and analyzed by performing a Chi-square test, Fisher's exact test, independent t-test, and repeated measures ANOVA using SPSS/WIN 23.0. Results: This study showed improvement in the basic psychological needs (F=3.90, p=.010) in the experimental group compared to the control group. Specifically, competence (F=2.93, p=.035), relatedness (F=2.89, p=.045), and self-regulatory ability (F=3.11, p=.028) improved significantly. Conclusion: Study findings indicate that the smartphone overdependence prevention program based on the Self-determination theory could be an effective intervention for improving basic psychological needs and self-regulation ability. Therefore, this program could be an efficient strategy for smartphone overdependence prevention in university students.

• Journal of the Korean BIBLIA Society for library and Information Science
• /
• 제29권3호
• /
• pp.89-109
• /
• 2018

This study investigates the influence of project-based learning method on the self-directed learning and problem-solving abilities of students taking the 'Media Center Management' course in Library Information Science (LIS). During this study, two tests measuring students' self-directed learning and problem-solving abilities were conducted, containing 48 items divided into 8 categories and 30 items divided into 5 steps of problem-solving processes, respectively. By utilizing the correspondence sample T-test during this study, statistically significant results were found in all categories of self-directed learning, excluding the 'self-understanding' category. In addition, significant differences were found in the 5 steps problem-solving processes as well. Subsequently, an in-depth interview was conducted, inquiring into the students' perspectives on the difficulty of attending classes, the content of lectures, the appropriateness of assignments, the validity of the evaluation method, the relationship with their team members, and the benefits acquired from completing the assignments. Finally, suggestions for future research were presented.

• Journal of the Korean earth science society
• /
• 제23권8호
• /
• pp.666-675
• /
• 2002

The purpose of this study was to develop the level-defferentiated Web Based Instruction(WBI) program, to examine its effects on the science achievement self-directed learning characteristics, and the students’ perceptions on the WBI learning. For this purpose, the advanced and complementary WBI program of level-differentiated curriculum was developed to adapt to class fields and examine instruction facilitating efficiency. Designed and developed the WBI program make it possible to teach students according to the level-differentiated learning for the chapter, ‘weather and climate’ in high school science curriculum. The results of this study are as follows: First, level-differentiated WBI was effective to encourage self-concept, learning eagerness, future-oriented self-apprehension, creativity, self-assessment of the student’s self-directed teaming characteristics. There was no interaction effect of treatment and students’ learning ability at the self-directed learning characteristics. Second, the scores of science achievement of WBI group were significantly higher than those of conventional lecture group. There was interaction effect of treatment and students’ learning ability. However level-differentiated WBI has no effect on openness, initiative, responsibility of the student’s self-directed learning characteristics. There was interaction effect of treatment and students’ learning ability at the science achievement, Third, in the perception questionnaire of WBI teaming, many students showed the WBI teaming was good in terms of causing interaction between learners and web based learning materials including various images and animations. However there are several students who showed learning difficulties. For example they wonder which part is more important and what order is proper to study in hypertext environment.

• Journal of The Korean Association For Science Education
• /
• 제36권3호
• /
• pp.445-455
• /
• 2016

The purpose of this study is to identify the structural relationship among students' grit, interest, self-regulation ability, task-commitment and achievement within science learning. Our concern is understanding how grit is related to the other non-cognitive variables, i.e., interest, self-regulation ability, and task-commitment, which are widely known as significant predictors of science achievement. Based on literature review, we evaluated two hypothetical models in the frame of structural equation modeling as follows: first, grit was assumed to mediate relations of interest and self-regulation ability, and interest and task-commitment. Second, grit was assumed to have a direct effect on self-regulation ability and task-commitment independent of interest. In both models, grit was assumed to be indirectly associated with science achievement. A total number of 180 high school students (77 boys, 103 girls) participated in surveys on grit, interest, self-regulation ability, and task-commitment and reported their science test scores on mid-term/final exams. Results revealed that students' grit and interest were indirectly associated with their science achievement with the mediation of their self-regulation and task-commitment. We also found that task-commitment was highly correlated with interest and self-regulation. Furthermore, we found different patterns of correlations within the five variables between female and male students. From these results, we suggested that researchers need to investigate whether students' grit and task-commitment can explain their interest decreasing as they move to higher grade levels, how teachers can help students to maintain their interest in learning science from early childhood, and relationships of these non-cognitive variables and science achievement.