• Journal of Broadcast Engineering
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• v.17 no.6
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• pp.990-1003
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• 2012

In this paper, the possibility and necessity of the digital broadcasting propulsion in AM and FM is presented based on DRM and DRM+ transmission modes, They are the members of series technological family in digital radio development. As the frequency utilization, the application of DRM+ is flexible in any mode such as IN-BAND or OUT-OF-BAND. When the digital audio broadcasting is planned at LOW-VHF bandwidth such as TV channel No.5 and NO.6 being adjacent to FM band and OUT-Of-BAND DRM+ technology is applied, there is no collision and jamming. Particularly, in the IN-BAND Hybrid mode, it is mentioned that there was the difficulty problem for multiple SFN transmitters uses. Not like the IN-BAND mode the OUT-OF-BAND mode lets multiple transmitters, because neighbor transmitters do not interfere each other. Digital transmitter can be combined with the existing FM transmitter. The intensity of power and size of area can be easily determined according to local broadcasters' condition. And the OUT-OF-BAND mode is advantageous for AM/FM integration in digital radio receiver manufacturing, which makes the conversion schedule much shorter.

• Proceedings of the Korean Vacuum Society Conference
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• 2014.02a
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• pp.425.1-425.1
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• 2014

Thermal transport in nanomaterials is not only scientifically interesting but also technological important for various future electronic, bio, and energy device applications. Among the various computation approaches to investigate lattice thermal transport phenomena in nanoscale, the atomistic nonequilibrium Green's function approach based on first-principles density functional theory calculations appeared as a promising method given the continued miniaturization of devices and the difficulty of developing classical force constants for novel nanoscale interfaces. Among the nanometerials, carbon atomic chains, namely the cumulene (all-doulble bonds, ${\cdots}C=C=C=C{\cdots}$) and polyyne (alternation of single and triple bonds, ${\cdots}C{\equiv}C-C{\equiv}C{\cdots}$) can be considered as the extream cases of interconnction materials for nanodevices. After the discovery and realization of carbon atomic chains, their electronic transport properties have been widely studied. For the thermal transport properties, however, there have been few literatures for this simple linear chain system. In this work, we first report on the development of a non-equilibrium Green's function theory-based computational tool for atomistic thermal transport calculations of nanojunctions. Using the developed tool, we investigated phonon dispersion and transmission properties of polyethylene (${\cdots}CH2-CH2-CH2-CH2{\cdots}$) and polyene (${\cdots}CH-CH-CH-CH{\cdots}$) structures as well as the cumulene and polyyne. The resulting phonon dispersion from polyethylene and polyene showed agreement with previous results. Compared to the cumulene, the gap was found near the ${\Gamma}$ point of the phonon dispersion of polyyne as the prediction of Peierls distortion, and this feature was reflected in the phonon transmission of polyyne. We also investigated the range of interatomic force interactions with increase in the size of the simulation system to check the convergence criteria. Compared to polyethylene and polyene, polyyne and cumulene showed spatially long-ranged force interactions. This is reflected on the differences in phonon transport caused by the delicate differences in electronic structure.

• Journal of the Korea Society of Computer and Information
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• v.21 no.8
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• pp.127-141
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• 2016

With more emphasis on importance of software, many countries try to provide software education. Of course Korea includes informatics courses in 2015 revised curriculum, so that software education will be administered briskly in soon. However there are practical challenges including a lack of teaching hour in classes and the monotony of educational contents which occurs with that. To solve these problems, this research develop software education curriculum model that could be practically used for both middle and high school. First this study compare the curriculum of Korea to that of United States and United Kingdom. After analyzing the result, the curriculum model for middle and high school is developed. The curriculum model can be classified into three types, middle, high and advanced-high levels and include key concepts like collaboration and convergence, computational thinking, computing practice and programming, computers and communications devices, community, global, and ethical impacts. To assess the feasibility of our software education curriculum model, examination was made by expert group and a hearing was held by related researchers. Then the model was modified in a way that adjustable to Korea education system. This study provides some important guidances on designing a curriculum for software education at middle and high school. However, there still are difficulty adjusting to the elementary school and university course. To be able to further research, same kind of studies on elementary school and university course need to be done. Also, continuous modifications are required to reflect reality including technological advance, curriculum, and changes of education system.

• Journal of the Ergonomics Society of Korea
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• v.25 no.3
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• pp.49-60
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• 2006

Technological encroachment provides human operators with flood of information that must be analyzed to understand the environment and make judgments that lead to strategic actions. Further, the environment is not static and therefore uncertain, changing its aspect dynamically. Complexity accompanied with its dynamics imposes substantial difficulty to human operators' task. Criticality of having situational understanding becomes more important than ever. Situationalunderstanding requires the human operators possessing tacit knowledge in order for them to make the sense out of the situation while interacting with information from many heterogeneous sources, the notion of sensemaking. Sensemaking refers to the process of developing mental framework to assemble pieces of information representing different aspects of the environment that can be used to develop one's own actionable knowledge to implement their judgments in the uncertain environment. Therefore, judgment process and performance is a key component of sensemaking process. Among many judgment and decision making models, the lens model with its extension can be utilized to partially describe the judgmental aspect of sensemaking. One of the lens model parameters, unmodeled knowledge, can be a corresponding quantitative measure for the tacit knowledge that plays an important role in sensemaking. In this paper, a comprehensive literature for sensemaking is provided to formally define the notion of sensemaking in the military domain. Also, it is proposed that there is a crucial link between the sensemaking and human judgment process and performance from the lens model perspective. Potential implications for experimental framework are also proposed.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.15 no.2
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• pp.462-470
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• 2011

ARS (Automatic Response Systems) based on VUI (Voice User Interface) and TTI (Touch Tone Interface) are one of the most widely used communication systems. Despite common usages, however, inconvenience of ARS is continually pointed out. This may stem from lack of human-centered studies aside from technological development. In this paper, we provide guidelines for designing ARS by analyzing hindrance factors of usability of ARS menu structure. We had selected two call-centers using ARS, and carried out an experimental study where subjects performed the task of "returning books." After that, they completed questionnaires and interviews. We identified four problems: the complex menu structure, lack of representativeness on the menu name, users' awareness of location, and a difficulty to move among menus. And we partially discussed the ways of avoiding the problems.

• The Mathematical Education
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• v.58 no.3
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• pp.423-442
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• 2019

Stepping into the beginning of the fourth industrial revolution, we need new mathematics education plans and policies to foster talent in people for future. Investigating the present condition and teachers' perceptions of mathematics education in schools is an essential process in making mathematics education plans and policies that reflect the periodical changes and social needs. Thus, we developed a survey to investigate teachers' perceptions and present condition of mathematics education, conducted the survey for teachers in elementary, middle, and high schools, and analyzed the results of the survey. In this study, focusing on the results of the survey, we interpreted the results and provided implications for mathematics educational policies. Through frequency analysis of individual questionnaires and crosstabulation analysis between questionnaires, we could provide mathematics teachers' overall perceptions of mathematics education and basic information on the conditions of mathematics education in the schools. In addition, the findings of this study suggest that policymakers should consider the followings when developing new mathematics education plans and policies: having the proper number of students per class, reducing non-teaching work, supporting teachers' expertise in evaluation, improving Internet access and technology equipment, supporting the school administrators' change of perceptions of mathematics education, retraining teachers in the active use of ICT or technological tools, and supporting students having difficulty learning mathematics.

• The Journal of the Korea institute of electronic communication sciences
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• v.17 no.6
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• pp.1157-1166
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• 2022

With the advent of the non-face-to-face era, a new type of digital sexual crime with avatars is emerging on the Metaverse virtual reality platform. Due to the lack of clearly established in legal and regulatory systems, it is challenging to punish offenders and acquire digital proof for sexual crimes using these avatars. This research aims to suggest a service and technological solution is development platform that may assist crime prevention and the collection of digital evidence, with a particular emphasis on digital sex crimes that occur in the metaverse, a virtual reality realm. This study explores the reasons behind the difficulty of legal application in the metaverse and then determines the types of digital sex crimes that may occur in the metaverse. In addition, it is suggested what service components the metaverse should contain from the stage of construction and design, can be utilized what element of metaverse in order to prevent illegal activity of avatars.

• Journal of the Korea Institute of Building Construction
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• v.23 no.4
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• pp.429-440
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• 2023

This research investigates the deployment of waterproofing technologies in construction, with a specific focus on augmenting worker safety, work environment, and solve the difficulty of securing skilled workers. Implementing liquid waterproofing cement equipment resulted in a remarkable increase in adhesion performance by around 20%, coupled with a twofold acceleration in operational speed. The application of primer spraying apparatus led to a two-fold improvement in both penetration and adhesion performance, concurrently boosting the work speed by approximately the same factor. With urethane spraying equipment, the workload could be reduced to a third for the same layer thickness, adhesion performance enhanced by approximately 1.4 times, and workability improved by about 1.4 to 1.5 times. These findings suggest that such technological interventions can potentially enhance work efficiency, improve the quality of output, and mitigate safety accidents that are commonplace in manual operations. Furthermore, these advancements present promising solutions to the ongoing challenges of sourcing highly-competent workers in the industry.

• International conference on construction engineering and project management
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• 2020.12a
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• pp.333-342
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• 2020

Due to the enhancing environmental concerns worldwide with the need of increasing demand for sustainability of building design, maintenance and operation, key stakeholders including the government and developers in many countries strike for the benefits in implementing the green design and building concepts in constructing, infrastructure as well as the buildings. Different countries have their standards or certifications for green buildings while the adoption rate of BEAM-Plus in HK is relatively less compared with other developed countries such as Europe, USA and Japan. Therefore, in the present research, BEAM-Plus, the beginning assessment method of green standard implemented in HK, will be mainly discussed. Current situation of BEAM-Plus implementation in HK will be reviewed and then adopt a systematic approach via literature review and research paper, questionnaire with Analytic Hierarchy Process (AHP) method to depict the opportunities and challenges from the perspective of government and developers regarding implementing BEAM-Plus in HK and thus investigate the implementation gaps. It is found that for both the macro level of opportunity and challenge, the most important criterion is political, in which the weighting value are 0.3114 and 0.2321 respectively. It is obvious that government plays a critical and significant role in affecting the development of BEAM plus. Technological difficulty is also an important factor that challenging and hindering the implementation of BEAM plus, the weighting value is 0.2194 under challenge hierarchy. More experts and professionals should be imported to Hong Kong to enhance the technique is building green buildings. At the end of this paper, solutions and actions will also be suggested and concluded in alleviating the challenges. Finally, solutions and actions are suggested and concluded in alleviating the challenges. Findings from this research can guide developers to consider adopting green elements, government and Green Building Council in HK to review green buildings' policy.

• Journal of Practical Engineering Education
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• v.15 no.3
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• pp.597-603
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• 2023

This study evaluates the AI digital competencies of teachers and presents a step-by-step framework for teacher's AI digital competencies that can be utilized in training. To do this, AI digital competencies were analyzed from the perspective of utilization and disposition, linked with the Technological Pedagogical Content Knowledge (TPACK) perspective. Then, as a precedent for step-by-step teacher AI digital competencies, the 3-step competency of the British Education and Training Foundation and the UNESCO ICT Teacher Competency Framework were presented. In this study, teacher's AI digital competencies were divided into three stages: entry, adaptation, and leadership, considering precedent research and domestic conditions. The initial entry stage passed the validity test in the second round of the Delphi survey, and the other two stages passed in the first round. The final entry stage is described as a stage where teachers understand AI digital but have difficulty implementing it, the adaptation stage is a level applied to standard curricula, and the leadership stage is a level where AI digital is applied in advanced courses and teachers serve as models for others. Through the overall AI digital competencies presented in this study, detailed competency development is possible, and it can be used as a reference material for developing evaluation items.