• Advances in nano research
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• v.14 no.1
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• pp.27-43
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• 2023

This article investigates the energy harvesting characteristics of a magneto-electro-elastic (MEE) cantilever beam reinforced with carbon nanotubes (CNT) under transverse vibration. To this end, the well-known lumped parameter model is used to represent the coupled multiphysics problem mathematically. The proposed system consists of the MEE-CNT layer on top and an inactive substrate layer at the bottom. The substrate is considered to be made of either an isotropic or composite material. Basic laws such as Gauss's Law, Newton's Law and Faraday's Law are used to arrive at the governing equations. Surface electrodes across the beam are used to harvest the electric potential produced, together with a wound coil, for the generated magnetic potential. The influence of various distributions of the CNT and its volume fraction, substrate material, length-to-thickness ratio, and thickness ratio of substrate to MEE layer on the energy harvesting behaviour is thoroughly discussed. Further, the effect of external resistances and changes in substrate material on the response is analysed and reported. The article aims to explore smart material-based energy harvesting systems, focusing on their behaviour when reinforced with carbon nanotubes. The results of this study may lead to an improved understanding of the design and analysis of CNT-based smart structures.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.46 no.2
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• pp.22-31
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• 2023

Governments around the world are enacting laws mandating explainable traceability when using AI(Artificial Intelligence) to solve real-world problems. HAI(Human-Centric Artificial Intelligence) is an approach that induces human decision-making through Human-AI collaboration. This research presents a case study that implements the Human-AI collaboration to achieve explainable traceability in governmental data analysis. The Human-AI collaboration explored in this study performs AI inferences for generating labels, followed by AI interpretation to make results more explainable and traceable. The study utilized an example dataset from the Ministry of Oceans and Fisheries to reproduce the Human-AI collaboration process used in actual policy-making, in which the Ministry of Science and ICT utilized R&D PIE(R&D Platform for Investment and Evaluation) to build a government investment portfolio.

• International Commerce and Information Review
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• v.5 no.1
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• pp.125-134
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• 2003

The rapid development of e-commerce in the world has resulted in great challenges to the traditional taxation systems all over the world. As a developing country, anna should take into careful consideration the characteristics of e-business and work out countermeasures to meet the challenges. This thesis at first offers an introduction to the characteristics of e-business and the different kinds of taxes in e-business, then gives an overview of the present taxation situation in e-business and analyzes loopholes in the tax laws concerning it, and finally provides some suggestions concerning online taxation in the development of e-business.

• Journal of the Korea Society of Computer and Information
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• v.19 no.10
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• pp.117-124
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• 2014

Software Development Security is defined as a sequential procedure such as deleting potential security vulnerability for secure software development, designing or implementing various functions with considering security, and so on. In this paper, we research on domestic or international hacking cases that could damage us mentally or financially. Seventy five percent of Web-site attacks abuses weak points of application programs, or software. We also research on major issues related to software development security with these demerits. And then, we propose public and private laws, regulations, or systems and give some examples with detailed descriptions.

• Korean Chemical Engineering Research
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• v.43 no.1
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• pp.181-185
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• 2005

The flash point is one of the most important combustible properties used to determine the potential for fire and explosion hazards of industrial material. An accurate knowledge of the flash point is important in developing appropriate preventive and control measures in industrial fire protection. The flash points for the n-butanol+n-propionic acid and n-propanol+n-propionic acid systems were measured by using Tag open-cup apparatus(ASTM D 1310-86). The experimental data were compared with the values calculated by the laws of Raoult and van Laar equation. The calculated values based on the van Laar equation were found to be better than those based on the Raoult's law.

• Wind and Structures
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• v.7 no.4
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• pp.251-264
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• 2004

The effects of a class of nonlinear Tuned Mass Dampers on the aeroelastic behavior of SDOF systems are investigated. Unlike classical linear TMDs, nonlinear constitutive laws of the internal damping acting between the primary oscillator and the TMD are considered, while the elastic properties are keept linear. The perturbative Multiple Scale Method is applied to derive a set of bifurcation equations in the amplitude and phase and a parametric analysis is performed to describe the postcritical scenario of the system. Both cubic- and van der Pol-type dampings are considered and the dependence of the limit-cycle amplitudes on the system parameters is studied. These new results, compared with the previously obtained bifurcation scenario of a SDOF aeroelastic oscillator equipped with a linear TMD, show a detrimental effect on the maximum limit-cycle amplitude reduction of the nonlinear TMD. However, the analyses evidence that in the parameter region away from the perfect tuning condition the nonlinear connection can be used to tune the system with an enhancement of the limit-cycle amplitude reduction.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.57 no.5
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• pp.845-851
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• 2008

A simple RMRAC (Robust Model Reference Adaptive Control) scheme for the PMSM (Permanent Magnent Synchronous Motor) is proposed in the synchronous frame. A current control of PMSM is the most inner loop of electro-mechanical driving systems and it requires a fast and simple control law to play a foundation role in the control hierarchy. In the proposed synchronous current model, the input signal is composed of a calculated voltage by proposed adaptive laws and real system disturbance. The gains of feed-forward and feedback controllers are estimated by the proposed modified Gradient method respectively, where the system disturbances are assumed as filtered current tracking errors. After the estimation of the system disturbances from the tracking errors, the corresponding voltage is fed forward to control input voltage to compensate for the disturbances. The proposed method is robust against high frequency disturbance and has a fast dynamic response. It also shows a good real-time performance due to it's simplicity of control structure. Through the simulations and real experiments, efficiency of the proposed method is verified.

• Journal of the Ergonomics Society of Korea
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• v.26 no.2
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• pp.15-20
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• 2007

The purpose of this study is to compare assessment techniques for Korean characters entry methods of mobile phones. This study was performed based on survey of relevant existing studies. The assessment techniques were classified into three: 1) predicting entry time using conceptual models such as Fitts' law, Hick-Hyman's law and KLM-GOMS model (conceptual model); 2) counting the number of pressing button(number of pressing button); and 3) measuring performance or rating subjective measures using real mobile phones(real mobile phone). The comparison revealed that the assessment results were different depending upon the techniques used. The results from the conceptual model using only Fitts' law and the number of pressing button were opposite to those from techniques of the real mobile phone and conceptual model using Fitts' and Hick-Hyman's laws. Based on this result and suggestions provided by the literature, it is recommended that for more precisely assessing interfaces of mobile phones such as Korean characters entry method, real mobile phones be used instead of the conceptual models.

• Proceeding of Spring/Autumn Annual Conference of KHA
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• 2005.11a
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• pp.57-61
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• 2005

The objectives of this study are to illustrate an alternative housing type responding to the social requirements and customers' needs, to suggest the improvement plan for the related laws and regulations through survey of the actual condition for housing buildings such multi have been raised in classification due to that the existing law systems including the current use classification of residential buildings have been defined unclearly. Especially, various social problems have yielded in line with emergence of the housing type which is not legally classified as residential however used for the living purpose practically. Current zoning planning and related law system have rigidity. So, It is required to introduce a flexible classification system which protects the residential environment based on the housing purpose, function and habitability and provides correspondence between residence and ownership/management method. The legal classification system should be revised in a way that the housing use classification corresponds with the zoning system through breakdown of the use classification system

• Journal of Korean Academic Society of Home Health Care Nursing
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• v.27 no.3
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• pp.241-249
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• 2020

Purpose: This study aimed to investigate possible ways to expand the services of home-visit nursing through a review of the progress, achievements, and obstacles of home-visit nursing; a pilot project of an integrated home-service; the application of the Omaha System; as well as a case analysis of providing home-visit nursing services. Method: An integrated review was conducted using various source materials, including laws, previous studies, and a case analysis. Results: In case analysis of providing visiting nursing service, rehabilitation nursing, end-of-life nursing, and dementia care showed high nursing needs. It was necessary that the various home visit nursing services in the intervention area of the Omaha System, administrative services, case management, and center operation activities were all included in the payment systems of long-term care insurance. Conclusion: In the future, home visit nursing services of long-term care insurance should be reborn in the form of a center for integrated case management in the community, which would set long-term goals until the time of a client's death and encompass the realm of human rights for health, quality of daily life, and a dignity of life.