• Journal of the Korean Geosynthetics Society
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• v.16 no.4
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• pp.33-41
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• 2017

In this study, the increment effect of safety factor according to increasing of horizontal permeability coefficient is analyzed when geocell is installed on the slope for protection. To evaluate the horizontal permeability and reinforcement effect, the laboratory tests such horizontal permeability test were conducted. According to the laboratory test results, as the porosity rate of geocell increases, the coefficient of horizontal permeability is also increased. And also, regardless of the different types of filled materials, the coefficient of horizontal permeability is improved in a geocell reinforced ground compare with the non-reinforced ground. Laboratory test results and the rainfall intensity were applied to the numerical modeling of slope for seepage analysis and stability analysis of slope by using Soilworks, numerical analysis program. As a result of the slope stability analysis, it is confirmed that the installed geocell on the slope facilitates the drainage of water on the surface of slope. Hence, the ground water elevation is suppressed. Therefore, the safety factor of the slope is increased by the increasing of the internal friction angle, apparent cohesion, and coefficient of horizontal permeability by reinforcing the slope with geocell.

• Therapeutic Science for Rehabilitation
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• v.9 no.4
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• pp.107-120
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• 2020

Objective : The purpose of this study was to investigate the effectiveness and basis of rehabilitation intervention in patients with spinal cord injury by systematic review and meta-analysis of randomized controlled studies. Methods : Two researchers independently searched and selected a study published in an academic journal using a search term in an international thesis database. A total of 21 studies met the selection criteria, and qualitative evaluation of the study was conducted using the PEDro Scale. Meta-analysis was performed using Comprehensive Meta-Analysis 3.0 program. Results : A total of 713 subjects were included. The results of the meta-analysis showed a score of 0.406 (95.0% confidence interval: 0.221 ~ 0.591) for intervention using physical activity and 0.505 (95.0% confidence interval: 0.449 ~ 1.528) for electronic stimulation therapy, which showed medium effect; educational intervention had a 0.248 (95.0% confidence interval: 0.033 ~ 0.464), and mixed intervention 0.280 (95.0% confidence interval: 0.122 ~ 0.438). It was shown that the effect of small (small). There was a significant heterogeneity in the statistical heterogeneity test, and thus the random effects model was selected and analyzed. Conclusion : The results showed that rehabilitation interventions were effective for patients with spinal cord injury. During the rehabilitation of spinal cord injury patients, clinicians are expected to contribute to the development of programs to improve their lifestyles.

• Journal of Korean Society of Transportation
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• v.25 no.5
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• pp.33-42
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• 2007

The current left-turn split model adopted in COSMOS has an inherent limitation when a loop detector in the left-turn lanes was disconnected for a period of time. In this instance, the current model always allocated minimum green time to the left-turn phase, thus optimal split and efficient signal operation for the intersection was not guaranteed. In this paper, four mathmatical models using detector information of the intersection and four empirical models using historical profiles were developed and investigated for different traffic conditions to improve the operational efficiency of the intersection. From the model evaluation test, the empirical model using a four-week historical profile produced the least error among the eight models investigated. NETSIM simulation test results also showed that the proposed model could give significantly reduced delay time as compared to the current model. From these results, the operational efficency of the signalized intersections under the real-time control can be greatly improved by using the model proposed in case of the left-turn detector failure.

• Journal of Information Management
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• v.41 no.4
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• pp.23-40
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• 2010

The needs for independent 'lifelong learning' is on the rise for the individuals living in today's fast-paced society. As a result, the significance of 'information literacy' as the core requirement for lifelong learning has become widely recognized. Some countries have even established standards for information literacy at the national level, and introduced programs to improve the overall level of information literacy in the school curriculum. In Korea, various studies have been done to identify the importance of information literacy, and also there are increasing offerings of information literacy programs in regular curriculum. Based on the result of self-efficiency assessment by the students who attended the information literacy courses, this study tries to examine the effects of those programs. It consequently confirms that these curriculums resulted in improvement of the information literacy of the students, and also provide some suggestions and guidelines for the design of the curriculum for information based on the findings.

• Journal of Korean Tunnelling and Underground Space Association
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• v.10 no.4
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• pp.421-430
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• 2008

In discontinuous rock masses, hydraulic-mechanical coupled analyses are required since groundwater flow in joints have a great influence on the stability of a subsea tunnel. In this study, a sensitivity analysis was performed based on coupled analysis to verify the routine which can estimate the safety factor of a tunnel in discontinuous rock mass. To this end, 324 cases of numerical calculations were performed with a commercial program, UDEC-2D. As a result, it was confirmed that the proposed routine for coupled analysis in discontinuous rock mass could give a reasonable result for the estimation of safety factor of a tunnel. Therefore, it is expected that the safety factor estimation method used in this study can be effectively applied for the stability estimation of a subsea tunnel in discontinuous rock masses.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.21 no.6
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• pp.250-265
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• 2022

Positive effects such as significantly reducing traffic accidents caused by human error can be expected by the introduction of Automated vehicles (AV). However, as new traffic safety issues are expected to occur in the future due to errors in H/W or S/W of autonomous vehicles and lack of its function, it is necessary to establish a scenario to evaluate the driving safety of AV. Therefore, in this study, functional scenario was developed to evaluate the driving safety of AV based on traffic accident data of the National Police Agency. Using the GIS program, QGIS, traffic accident data that occurred in the toll gate and ramp sections of expressway were extracted and accident summary items were checked to classify the types of accident. In addition, based on the results of accident type classification, functional scenario were developed that contains various dangerous situations in the tollgate and ramp sections.

• Journal of the Korean GEO-environmental Society
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• v.24 no.5
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• pp.13-20
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• 2023

The Gangneung region has an environment suitable for the formation of organic soil, and there is an alluvial layer in which sedimentary sand layers are distributed on the upper and lower parts of the organic soil. In order to evaluate the seismic safety of the railway roadbed passing through the Gangneung area, a railway roadbed and ground model considering the similarity ratio was fabricated, a shaking table test was conducted, and the seismic stability was evaluated by comparing the effective stress analysis results. The applied seismic waves were artificial seismic waves, Gyeongju seismic waves, Borah seismic waves, Nahanni seismic waves, and Tabas seismic waves. It became. Due to the ground reinforcement effect by jet grouting applied to the lower ground of the new roadbed, the displacement of the new roadbed was found to be reduced from a minimum of 33.7% to a maximum of 56.7% compared to the existing roadbed. The shaking table test results were verified by effective stress analysis using the Finn model of the Flac program, and showed a similar trend to the shaking table test values.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.9
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• pp.407-421
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• 2016

This paper reports a meta-analysis of sixteen studies that evaluated the efficacy of cognitive behavioral therapy (CBT) for persistent primary insomnia. PubMed, Cochrane Library, EMBASE, CINAHL and several Korean databases were searched between January 2015 and June 2015. The main search strategy involved the terms that indicate CBT-I (Cognitive Behavioral Therapy-Insomnia) and presence of insomnia. Methodological quality was assessed using Cochrane's Risk of Bias. Data were analyzed by the RevMan 5.3 program of Cochrane Library. Sixteen clinical trials met the inclusion criteria, resulting in a total of 1503 participants. Stimulus control, sleep restriction, sleep hygiene education, and cognitive restructuring were the main treatment components. CBT-I was conducted for a mean of 5.4 weeks, 5.5 sessions, and an average of 90 minutes per session. The effects of CBT-i on total sleep time (d=-0.31), sleep onset latency (d=-0.29), awakening time after sleep onset (d=-0.55), sleep efficiency (d=-0.70), insomnia severity (d=-0.77) and sleep belief (d=-0.64) were significant. Overall, we found a range from small to moderate effect size. CBT-I also was effective for anxiety (d=-0.30) and depression (d=-0.35). The findings demonstrate that CBT-I interventions will lead to the improvement of both sleep quality and quantity in patients with insomnia.

• Journal of Korea Technology Innovation Society
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• v.19 no.1
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• pp.105-136
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• 2016

This paper analyzed the qualitative evaluation indicators of the SYSTEM sector of the LINC program, which aimed at strengthening ability of regional universities through the activities of industry-academia cooperation (IAC). By using interview data and the program reports of universities, this research explored the problems of the indicators and suggested improvement measures which could lead to performance creativity. According to research results, in university system reform for activating IAC, some improvements are required as follows: limiting excessive expansion of IAC-friendly faculty evaluation; and evaluating soft aspects in the reform of academic affairs. In relation to strengthening of ability of the IAC organization, the indicators need to be amended as follows: enhancing the role of channel of IAC Foundation; strengthening the function of planning team of the IAC Foundation; and inducing development of own model of universities for IAC. As regards expansion of IAC infrastructure, it is necessary to enlarge the manpower who can develop programs of the support center in the foundation and to secure of operators for effective operation of joint-using equipments. Therefore, the indicators are required to be upgraded, considering these improvement direction.

• Journal of Engineering Education Research
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• v.18 no.3
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• pp.46-58
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• 2015

Informal engineering education program for high school students was developed to cultivate engineering literacy using the human resources and facilities of university. Plant factory, a smart farming technology, was selected as a main theme, and the novel engineering camp program involving engineering design activities and intra-linter-team works was planned. The camp program was applied to 38 high school students in an active learning classroom. Five teams were constructed according to elemental technologies such as biotechnology, information-communication technology, energy engineering, mechanical engineering and architectural engineering, and the students were participated in intra- and inter-team activities to achieve the final goal of 'the construction of a plant factory in school'. The team works were conducted according to the eight steps of engineering design process (identifying the problem and need, identifying criteria and constraints, brainstorming possible solutions, selecting the best possible solution, constructing a prototype, testing and evaluating the solution, communicating the solution, and refining design). Participants' satisfaction survey showed that the satisfaction on the contents of engineering design was 4.48 on 5-point Likert scale. The participants' satisfaction on creative activity and systematic methodology was 4.43 on 5-point Likert scale. 97% of participants responded positively to team works, and 92% of participants were satisfied with career mentoring activity supplied by undergraduate/graduate students. These results indicates that the engineering camp program involving engineering design activity and intra-/inter-team works can contribute to cultivate engineering literacy such as creativity, problem solving ability, collaboration, communication skills for high school students, and to increase their interests in engineering fields.