• Journal of the Korean Society for Railway
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• v.10 no.4
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• pp.444-450
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• 2007

The bi-modal tram guided by the magnetic guidance system has two car-bodies and three axles. Each axle of the vehicle has an independent suspension to lower the floor of the car and improve ride quality. The turning radius of the vehicle may increase as a consequence of the long wheel base. Therefore, the vehicle is equipped with the All-Wheel-Steering(AWS) system for safe driving on a curved road. Front and rear axles should be steered in opposite directions, which means a negative mode, to minimize the turning radius. On the other hand, they also should be steered in the same direction, which means a positive mode, for the stopping mode. Moreover, only the front axle is steered for stability of the vehicle upon high-speed driving. In summary, steering angles and directions of the each axle should be changed according to the driving environment and steering mode. This paper proposes an appropriate AWS control algorithm for stable driving of the bi-modal tram. Furthermore, a multi-body model of the vehicle is simulated to verify the suitability of the algorithm. This model can also analyze the different dynamic characteristics between 2WS and AWS.

• Journal of Fisheries and Marine Sciences Education
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• v.28 no.5
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• pp.1290-1300
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• 2016

This study investigates the awareness about competency assessment of the candidates for fourth class promotion, the competency factors and its operation, so that we find its problems and solutions. We carried out a questionnaire survey targeting the 64 candidates in April 2016. The results of this study are as follows. First, the candidates think that competency assessment system is helpful in improving reliability and fairness of promotion system and in eradicating nepotism. Second, the required competency factors needed to perform the role of fourth class public official are direction guidance, fostering, communication, integrative thinking, achievement management and power of execution in sequence. Third, in managing the competency assessment system, compulsory competency is considered more importantly than differentiated competency. Fourth, the candidates think that the competency assessment system can be applied advantageously to particular groups. Fifth, sufficient training period and information about the competency assessment system should be provided to solve the many problems caused by the lack of advance information about the system.

• The KSFM Journal of Fluid Machinery
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• v.7 no.5 s.26
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• pp.13-19
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• 2004

Centrifugal blowers are widely used for air handling units in industry applications. The blower has a centrifugal impeller and a scroll casing including a driving component such as an electric motor. The impeller takes forward or backward blades to induce flows into the blower, Comprehensive investigation according to the two kinds of blades is systematically carried out for a guidance of design for this kind research. It is observed that flow rate of the blower with forward blades is larger than that of the system with backward blades. Otherwise, the system noise is more pronounced in the case of the blower with forward blades. The reason is due to larger velocity from the rotating forward blades that pose obtuse angle with the circumferential direction. The distinguished characteristics are validated by a parallel experiments with a wind tunnel and in an anechoic chamber. Numerical analysis for the system shows detail information inside the blades and the casing. A series of figures to show the flow details offer deep understanding of the performance of a centrifugal blower with different blades.

• Journal of the Korean Institute of Educational Facilities
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• v.20 no.5
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• pp.35-42
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• 2013

It has already been four years as of 2013 since the Departmentalized Classroom System was first introduced following the Korean government's policy. However, no investigation had been made yet on whether the system is properly being managed in practice according to the presented standards, guidelines, and policy direction. Hence, an in-depth investigation and analysis were called for. In line with this, documents were researched, deliberation meetings of experts were held, and the system pilot was tested to develop indices to investigate the state of block-scheduled classes and classes for each student's academic level for the educational classes field. For the school management field, we developed indices to investigate the teachers' organization and their division of labor, administrative officers and work reduction, improvement of teachers' expertise, and the guidance of the students' school life. Based on the indices, we investigated the state of 24 schools, which manage an advanced school system, nationwide. The results showed that the Departmentalized Classroom System has now reached the settling stage, which is beyond the introductory stage, and that it needs to be systematically supplemented for it to be settled in a stable manner.

• Journal of the Korea Institute of Military Science and Technology
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• v.13 no.5
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• pp.717-724
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• 2010

The initial trajectory of a spheroid configuration bobbin for precision guidance has been investigated by analyzing its aerodynamic load and six-degree-of-freedom motion. The effects of changes in the spheroidal head configuration, flow angle and lateral center-of-gravity offset are numerically studied using the commercial software "FLUENT". A wind tunnel test is also conducted to validate the numerical scheme and to examine effect of the Reynolds number on the flow around the bobbin. It is shown that the size of the separation bubble formed on the surface decreases significantly when the Reynolds number is varied between 110,000 and 140,000. At a zero flow angle, an oblate spheroidal head shows relatively moderate rotation while a prolate spheroidal head shows rapid rotation. The bobbin with a spherical head shape has little effect on the flow direction; however, the oblate bobbin is sensitive to the flow angle. The roll motion of the bobbin is greatly influenced by the lateral center-of-gravity offset and maximum dispersion is observed at half of the radius.

• Journal of Information Technology Services
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• v.5 no.3
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• pp.63-82
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• 2006

This study is an approach to solve the problem concerning informatization and its investment of the existing information system. In this regard, IT Architecture is becoming a prominent figure, and great efforts are being taken to establishment of related infrastructure environment such as the 1st and 2nd pilot programs, ITA related law's legislation, and development of a reference model and its guidance. Especially, with 'the bill on the introduction and management of the information system' passing the National Assembly, all sorts of environment involved for the introduction of IT Architecture in the future such as establishment of the political foundation for IT Architecture introduction of public organizations, and integrated IT Architecture management system(G-ITAMS) is establishing the constituency. Therefore, this study aims to grasp accurately the actual condition concerning the introduction and utilization of IT Architecture at domestic public organizations, which was followed by investigation to present the right direction in the future, and the findings were discussed in the main body as follows:

• Wind and Structures
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• v.32 no.3
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• pp.179-191
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• 2021

A series of wind tunnel tests, including 1:50 sectional model tests, 1:50 free-standing bridge tower tests and 1:70 full-bridge aeroelastic model tests were carried out to systematically investigate the aerodynamic performance of the Hong Kong-Zhuhai-Macao Bridge (HZMB). The test result indicates that there are three wind-resistant safety issues the HZMB encounters, including unacceptable low flutter critical wind speed, vertical vortex-induced vibration (VIV) of the main girder and galloping of the bridge tower in across-wind direction. Wind-induced vibration of HZMB can be effectively suppressed by the application of aerodynamic and mechanical measures. Acceptable flutter critical wind speed is achieved by optimizing the main girder form (before: large cantilever steel box girder, after: streamlined steel box girder) and cable type (before: central cable, after: double cable); The installations of wind fairing, guide plates and increasing structural damping are proved to be useful in suppressing the VIV of the HZMB; The galloping can be effectively suppressed by optimizing the interior angle on the windward side of the bridge tower. The present works provide scientific basis and guidance for wind resistance design of the HZMB.

• Journal of Engineering Education Research
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• v.24 no.2
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• pp.3-11
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• 2021

In the COVID-19 era, it was implemented to be used as a basic material for setting the direction of learning support and student guidance for university institutions and professors who are experiencing confusion. The purpose of this study is to compare the actual status of daily-routines of COVID-19 period, general semester period, and vacation period, and to examine whether there is a difference between the period of general semester and COVID-19 period, and whether there is a difference in daily use of COVID-19 period depending on grade. For this reason, a questionnaire survey was conducted from April 23 to 29, 2020, targeting students of University A, which is a small-scale technical centered university in the region, and 754 students answered. As a result of the study, first of all, when we looked at the trends in the use of daily-routines by period of general semester, vacation period, and COVID-19 period, the trends of the general semester period and COVID-19 period were similar in the areas of learning and self-development. Second, there were statistically significant differences in sleep, relaxation, learning and other areas between the period of the general semester and the duration of COVID-19. Third, there were statistically significant differences over grade in relaxation, learning, development, and other areas.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.16 no.8
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• pp.2704-2719
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• 2022

Lately, neo-Chinese style furniture has been frequently noticed by product design professionals for the big part it played in promoting traditional Chinese culture. This article is an attempt to use big data semantic analysis method to provide effective design research method for neo-Chinese furniture design. By using big data mining program TEXTOM for big data collection and analysis, the data obtained from typical websites in a set time period will be sorted and analyzed. On the basis of "neo-Chinese furniture" samples, key data will be compared, classification analysis of overall data, and horizontal analysis of typical data will be performed by the methods of word frequency analysis, connection centrality analysis, and TF-IDF analysis. And we tried to summarize according to the related views and theories of the design. The research results show that the results of data analysis are close to the relevant definitions of design. The core high-frequency vocabulary obtained under data analysis, such as popular, furniture, modern, etc., can provide a reasonable and effective focus of attention for the designs. The result obtained through the systematic sorting and summary of the data can be a reliable guidance in the direction of our design. This research attempted to introduce related big data mining semantic analysis methods into the product design industry, to supply scientific and objective data and channels for studies on design, and to provide a case on the practical application of big data analysis in the industry.

• Korean Journal of Childcare and Education
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• v.19 no.2
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• pp.87-117
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• 2023

Objective: This study aimed to develop a documentation model that can support early chlildhood learning through play and facilitate the implementation of early childhood and play-oriented curriculum. Methods: This study utilized the design and development research methodology to derive components for the model through literature review and investigation research. In addition, the model was gradually improved through the 3rd expert review, and the validity of the model was verified through usability evaluation with 10 early childhood teachers. Results: This study identified 13 components and developed a flexible, selective, repetitive, and cyclic documentation model based on the 2019 revised Nuri curriculum. Model development is embodied and presented as a model-detailed model-detailed content. The model is presented in detail in the study. Conclusion/Implications: The documentation model developed in this study is expected to provide guidance to early childhood teachers and serve as a basis for future research on documentation in early childhood education. It is expected that it will be able to present the practical direction of records for play support for teachers in the field.