• Journal of IKEEE
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• v.27 no.4
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• pp.644-649
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• 2023

As the cell spacing decreases during the scaling process of DRAM(Dynamic Random Access Memory), the reduction in STI(Shallow Trench Isolation) thickness leads to an increase in sub-threshold leakage due to the passing word line effect. The increase in sub-threshold leakage current caused by the voltage applied to adjacent passing word lines affects the data retention time and increases the number of refresh operations, thereby contributing to higher power consumption in DRAM. In this paper, we identify the causes of the passing word line effect through TCAD Simulation. As a result, we confirm the DRAM operational conditions under which the passing word line effect occurs, and observe that this effect alters the proportion of the total leakage current attributable to different causes. Through this, we recognize the necessity to consider not only leakage currents due to GIDL(Gate Induced Drain Leakage) but also sub-threshold leakage currents, providing guidance for improving DRAM structure.

• Journal of The Korean Association For Science Education
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• v.43 no.6
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• pp.521-531
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• 2023

In this study, we analyzed contextualized NOS lessons planned by preservice teachers from the perspectives of PCK. Eight preservice teachers who had completed all of the curriculum at the College of Education located in Seoul participated in the study. CoRe and teaching and learning guidance were collected. Interviews were also conducted. We used analytical induction to analyze the collected data. The analyses of the results revealed that the NOS learning goals selected by the preservice teachers were different depending on the context of the NOS lessons. In addition, the preservice teachers were unable to sufficiently explain the value of learning NOS. All of the preservice teachers were worried that their students would not understand NOS properly, and they faced various difficulties in dealing with NOS and science content. They thought that if their students conducted experiments, errors could cause problems for students learning NOS. Meanwhile, they guessed their students' preconceptions and misconceptions of NOS based on their experience. The preservice teachers also thought that their students' concept of science and cognitive development stage would affect their NOS learning. Although the preservice teachers used various strategies to teach NOS, NOS was often not explicitly addressed. Also, they were reluctant to evaluate NOS in lessons. Based on the above results, educational implications for preservice teacher education were proposed.

• Korean Journal of Culture and Social Issue
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• v.14 no.1_spc
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• pp.299-317
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• 2008

The school drop-out among the youth has grown to become a serious social problem since about 2000 and calls for an attention to its seriousness. Therefore, this study reviewed the statitistical reports and the previous empirical findings on the school drop-out and integrated to establish a comprehensive understanding of this social phenomenon. The main concepts and terminologies on school drop-out, the current statistics, the possible causal factors and the usual trajectory the youth take after dropping-out of school were discussed to conceptualize the issue. Analyses indicated 12 characteristics of the students who dropped out of school. Those 12 characteristics were restructured according to the ecological conceptual model. The social instability and the financial crisis in the 1990's has eroded the stability of the primary environments of adolescents such as family and school. The family breakdowns from divorce and other reasons weakened psychological and financial support for adolescents. The diminished authority of teachers and school over students exposed conflicts between teacher and students, students' loss of purpose and interest in academic attainment. The adolescents showed emotional reponses like increased level of depression, helplessness, aggression, indicated cognitive reponses such as the loss of purpose and interest in studying, a heightened sense of uncertainty of the future, and behavioral responses like sexual acting out behaviors, and bullying. The unmet psychological needs of adolescents result in run-away and school drop-out behaviors, which in turn progress into juvenile delinquency as the society fails to provide adequate and appropriate guidance and interventions. The intervention strategies at the national level were proposed and the limitations of the study were discussed.

• The Journal of Korean Academy of Prosthodontics
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• v.61 no.4
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• pp.293-307
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• 2023

Jaw motion tracking, which is introduced in recent case reports, is a method which records the patient's individualized pathway of the mandibular movements along with facebow transfer, and reproduces the information in the virtual space of computer-aided-design/computer-aided-manufacturing (CAD-CAM) software. In this present case, a collapse of the occlusal plane was observed, due the loss of posterior teeth for a long period. Full-mouth rehabilitation with an increase in the occlusal vertical dimension was planned. First, the patient's mandibular movements were recorded on the newly established jaw relation by jaw tracking, and this information was assembled with the patient's intraoral data to create a virtual patient. Implant planning and diagnostic wax-up was done on the virtual patient, leading the fabrication of the provisional prosthesis. On the newly established jaw relation with an increase in the occlusal vertical dimension, canine guidance of the provisional prosthesis was checked. Finally, the provisional prosthesis was carried out to the definitive prosthesis. Using the advantages of the technologies in the digital dentistry, the patient was satisfied with the function and the esthetics after the treatment.

• Journal of the Korean Society of Marine Environment & Safety
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• v.29 no.7
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• pp.950-957
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• 2023

For safe mooring and towing between the ship and port, the equipment must be designed in accordance with the relevant international regulations. However, some small shipyards and engineering companies often do not fully comprehend the core contents. Therefore, the international regulations regarding towing and mooring equipment are reviewed and the bollard and chock are newly developed based on the Mooring Equipment Guideline 4 (MEG4) standards. A bollard is a mooring equipment used to fix a mooring rope to the hull. It has two columns and is mostly used in a figure eight pattern knots under the mooring condition. The chock, which is used to change the mooring rope direction coming into the ship from outside, is manufactured using a casting with curvature. The two mooring equipment are widely used in the stern, bow, and mid-side. Owing to the increase in the size of container vessels and LNG ships, the mooring rope load has increased and the safe working load of the mooring equipment must be revised. This study summarizes and examines the results of the allowable stress method obtained using finite element analysis modelling. To consider the mesh size effect, a reasonable criteria was suggested by referring the existing class guidance. Additionally, the safe working load was verified through nonlinear collapse analysis, and the elastic region against load increments was confirmed. Furthermore, the proposed evaluation method can be used to develop similar equipment in the near future.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.22 no.5
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• pp.163-181
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• 2023

Improving the detection performance of facilities corresponding to the sensors of autonomous vehicles helps driving safety. In the road and transportation field, research is being conducted to improve the detection performance of sensors by road infrastructure or facilities. As part of this on the development of autonomous driving support infrastructure, the shape of traffic cones and drums to ensure sufficient LiDAR detection performance even rainy conditions and maintain the line-of-sight guidance function in construction zones improvement effect. The principle was to increase reflection performance and ensure no significant difference in shape from existing facilities. Traffic cones were manufactured in square pyramid shapes instead of cones, and drums were manufactured in hexagonal and octagonal pillar shapes instead of cylinders. LiDAR detection data for the facility was confirmed on a clear day and with 20 mm/h and 40 mm/h rainfall. The detection performance of the square pyramid-shaped traffic cone and octagonal column-shaped drum was to the existing facility. On the other hand, deviations occurred due to repeated measurements, and significance could not be confirmed through statistical analysis. By reflecting these results, future studies will seek a form in which data can be obtained uniformly despite the diversity of measurement environments.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.43 no.6
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• pp.785-791
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• 2023

Risk management is essential for preventing accidents arising from uncertainties in TBM tunnel projects, especially concerning managing the risk of TBM tunnel collapse, which can cause extensive damage from the tunnel face to the ground surface. In addition, prioritizing risks is necessary to allocate resources efficiently within time and cost constraints. Therefore, this study aimed to establish a TBM risk database through case studies of TBM accidents and determine a risk priority for TBM tunnel collapse using the Bayes theorem. The database consisted of 87 cases, dealing with three accidents and five geological sources. Applying the Bayes theorem to the database, it was found that fault zones and weak ground significantly increased the probability of tunnel collapse, while the other sources showed low correlations with collapse. Therefore, the risk priority for TBM tunnel collapse, considering geological sources, is as follows: 1) Fault zone, 2) Weak ground, 3) Mixed ground, 4) High in-situ stress, and 5) Expansive ground. In practice, the derived risk priority can serve as a valuable reference for risk management, enhancing the safety and efficiency of TBM construction. It provides guidance for developing appropriate countermeasure plans and allocating resources effectively to mitigate the risk of TBM tunnel collapse.

• The Journal of the Convergence on Culture Technology
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• v.9 no.6
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• pp.861-866
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• 2023

Individuals with visual impairments face difficulties in accessing accurate information about medical services and medications, making it challenging for them to ensure proper medication intake. While there are healthcare laws addressing this issue, there is a lack of standardized solutions, and not all over-the-counter medications are covered. Therefore, we have undertaken the design of a mobile application that utilizes image recognition technology, barcode scanning, and QR code recognition to provide guidance on how to take over-the-counter medications, filling the existing gaps in the knowledge of visually impaired individuals. Currently available applications for individuals with visual impairments allow them to access information about medications. However, they still require the user to remember which specific medication they are taking, posing a significant challenge. In this research, we are optimizing the camera capture environment, user interface (UI), and user experience (UX) screens for image recognition, ensuring greater accessibility and convenience for visually impaired individuals. By implementing the findings from our research into the application, we aim to assist visually impaired individuals in acquiring the correct methods for taking over-the-counter medications.

• Korean Journal of Culture and Social Issue
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• v.9 no.2
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• pp.19-39
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• 2003

The purpose of this study was to investigate the degree of link with internet media and a internet addiction disposition of adolescents. The subjects were 500 students attending to middle and high schools consisted of male and female. The instruments were "the questionnaire on the present conditions of internet use" consisted of 14 items(Cronbach's α=.71) and "the internet addiction rating scale" consisted of 20 items(Cronbach's α=.73). These questionnaire were revised by this researcher. For data analysis, chisqure and ANOVA were used. The main results were as follows. First, a boy students and the vocational high school and the middle school each have more negative response than a girl students and the humanistic high schools in the present conditions of internet use and the judgement on a harmful object of internet space. Second, a boy students have higher than a girl students in an internet addiction disposition. Third, an internet addiction related with the times link with internet, the type of internet game, and the content of internet space(a lustful and violent objects). The various methods for the prevent with the internet addiction of adolescents discussed with based on the previous studies.

• Korean Journal of Culture and Social Issue
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• v.9 no.2
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• pp.127-164
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• 2003

This study investigates how Korean children and adolescents perceive their parents using the indigenous psychological approach. An open-ended questionnaire was developed by the first two authors to investigate reasons why children and adolescents feel grateful, respect, indebted, close, conflict, and distance with their parents. A total of 763 participants (212 grade three students, 267 grade eight students, and 284 grade eleven students) completed the questionnaire. The results can be summarized into three main points. First, the vast majority of children and adolescents feel grateful, respect, and indebted to their parents. They feel grateful, respect and indebted for the sacrifice and suffering they experience looking after the family. Moreover, they respects their parents because of their sincerity, blood relationship, benevolence, guidance and educational support. They feel indebted since they did not obey them, were not able to meet their expectations, and were not diligent in their schoolwork. They felt especially close to their mother. The conflict they felt was due to generational gap and in their academic performance. Second, age affects how they perceive their parents. The parent-child conflict increases with age. The feeling of indebtedness also increase with age. However, the feeling of gratefulness and respects decreases with age. The feeling of closeness with father also decreases with age. Third, socio-economic status and educational achievement of children and adolescent affect the perception of their parents. Those with higher academic grade and socio-economic status are more likely to feel respect and indebtedness and less likely to feel conflict and distance.