• Advances in aircraft and spacecraft science
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• 제6권6호
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• pp.479-495
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• 2019

Periodic cellular core structures included in sandwich panels possess good stiffness while saving weight and only lately their potential to act as passive vibration filters is increasingly being studied. Classical homogeneous honeycombs show poor vibracoustic performance and only by varying certain geometrical features, a shift and/or variation in bandgap frequency range occurs. This work aims to investigate the vibration filtering properties of the AUXHEX "hybrid" core, which is a cellular structure containing cells of different shapes. Numerical simulations are carried out using two different approaches. The first technique used is the harmonic analysis with commercially available software, and the second one, which has been proved to be computationally more efficient, consists in the Wave Finite Element Method (WFEM), which still makes use of finite elements (FEM) packages, but instead of working with large models, it exploits the periodicity of the structure by analysing only the unit cell, thanks to the Floquet-Bloch theorem. Both techniques allow to produce graphs such as frequency response plots (FRF's) and dispersion curves, which are powerful tools used to identify the spectral bandgap signature of the considered structure. The hybrid cellular core pattern AUXHEX is analysed and results are discussed, focusing the investigation on the possible spectral bandgap signature heritage that a hybrid core experiences from their "parents" homogeneous cell cores.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2003년도 추계학술대회
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• pp.1458-1463
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• 2003

This paper presents an improved identification algorithm of active magnetic bearing rotor systems considering sensor and actuator dynamics. An AMB rotor system has both real and complex poles so that it is very hard to identify them together. In previous research, a linear transformation through a fictitious proportional feedback was used in order to shift the real poles close to the imaginary axis. However, the identification result highly depends on the fictitious feedback gain, and it is not easy to identify the additional dynamics including sensor and actuators at the same time. First, this paper discusses the necessity and a selection criterion of the fictitious feedback gain. An appropriate feedback gain minimizes dominant SVD(Singular Value Decomposition) error through maximizing rank deficiency. Second, more improvement in the identification is achieved through separating the common additional dynamics in all elements of frequency response matrix. The feasibility of the proposed identification algorithm is proved with two theoretical AMB rotor models. Finally, the proposed scheme is compared with previous identification methods using experimental data, and a great improvement in model quality and large amount of time saving can be achieved with the proposed method.

• 한국CDE학회논문집
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• 제18권6호
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• pp.451-460
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• 2013

This paper presents the necessary elements and data flow in developing a monitoring system of energy usage for apartment houses with a Smart TV. Energy consumption data in each home are collected and analyzed in the HUB station by way of measuring instruments. And the amount of energy usage, such as electricity, gas, hot water, heating, water and other utilities are displayed through the Smart TV application. Energy consumption Database in the HUB station are processed and displayed in the browser of a Smart TV through XML, JAVASCRIPT and Flash. Smart TV users can get the energy consumption status through the energy consumption analysis display of the Smart TV application and improve the energy efficiency by comparing the usage patterns with neighboring houses. And the application display energy usage information, consumption ranking, rates to user as well. Furthermore, usage of last month or year can be compared to help to reduce the energy usage. The proposed system can provide the information about the amount of energy use to be reduced and the warning on the waste of energy.

• 제어로봇시스템학회논문지
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• 제12권12호
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• pp.1163-1168
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• 2006

Manufacturing technology for the production of high value-added fine chemical products is emphasized and getting more attention as the diversified interests of customers and the demand of high quality products are getting bigger and bigger everyday. Thus, the development of advanced batch processes, which is the preferred and most appropriate way of producing these types of products, and the related technologies are becoming more important. Therefore, high-precision batch distillation is one of the important elements in the successful manufacturing of fine chemicals, and the importance of the process operation strategy with quality assurance cannot be overemphasized. Accordingly, proposing a process structure explanation and operation strategy of such processes including batch processes and batch distillation would be of great value. We investigate optimal operation strategy and production planning of multi-purpose plants consisting of batch processes and batch distillation for the manufacturing of fine chemical products. For the short-term scheduling of a sequential multi-purpose batch plant consisting of batch distillation under MPC and UIS policy, we proposed a MILP model based on a priori time slot allocation. Also, we consider that the waste product of being produced on batch distillation is recycled to the batch distillation unit for the saving of raw materials. The developed methodology will be especially useful for the design and optimal operations of multi-purpose and multiproduct plants that is suitable for fine chemical production.

• 로봇학회논문지
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• 제10권2호
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• pp.61-69
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• 2015

In this paper, we propose and examine the feasibility of the robot-assisted behavioral intervention system so as to strengthen positive response of the children with autism spectrum disorder (ASD) for learning social skills. Based on well-known behavioral treatment protocols, the robot offers therapeutic training elements of eye contact and emotion reading respectively in child-robot interaction, and it subsequently accomplishes pre-allocated meaningful acts by estimating the level of children's reactivity from reliable recognition modules, as a coping strategy. Furthermore, for the purpose of labor saving and attracting children's interest, we implemented the robotic stimulation configuration with semi-autonomous actions capable of inducing intimacy and tension to children in instructional trials. From these configurations, by evaluating the ability of recognizing human activity as well as by showing improved reactivity for social training, we verified that the proposed system has some positive effects on social development, targeted for preschoolers who have a high functioning level.

• 한국정보전자통신기술학회논문지
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• 제3권4호
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• pp.83-90
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• 2010

IT융합과 같이 실세계 시스템과 연동되는 컴퓨팅환경의 발전과 더불어 시스템의 물리적 오류에 대한 분석 및 이를 활용한 예측 시스템의 요구가 점차 증가되고 있다. 이러한 물리적 오류는 자연적 현상 및 기계적 오류들과 밀접하게 연관되어지며 다양한 요소들에 의해 예측이 어렵다. 특히 승강기 시스템은 기기의 복잡성 때문에 다양한 문제를 발생 시키며 이들에 대한 효율적인 접근이 필요하다. 이에 본 논문에서는 승강기 시스템에서 이러한 기계적 오류 및 자연적 현상에서 발생 가능한 인자를 수집하고 이들의 분석을 통해 오류 발생을 예측할 수 있도록 데이터마이닝을 적용한 분석 관리 서비스 시스템을 제시하고자한다. 이를 통해 승강기에서 발생되는 오류를 미리 발견하고 경보해 줌으로써 만약의 사태에 대한 초기대응 및 인명구조에 적극적으로 대처할 수 있을 것이다.

• 국제초고층학회논문집
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• 제8권2호
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• pp.95-100
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• 2019

Whilst most research focuses on the reduction of operative energy use in buildings, the aspect of which (and how many) materials are used is often neglected and poorly explored. However, considering the continuous growth of the global population and the limited availability of resources, it is clear that focusing on operative energy alone is too short-sighted. The tasks lying ahead for architects and engineers cannot be accomplished with conventional methods of construction. With a share of 50-60% of global resource consumption, the building industry has a decisive impact on our environment. If business as usual continues, resources will be significantly depleted in a matter of decades. Therefore, researchers of the University of Stuttgart are investigating the concept of adaptivity as a promising method for saving resources in the built environment. The term adaptivity in the context of building structures was first introduced by Werner Sobek. It describes a method where sensors, actuators and control units are implemented in systems or facades in order to oppose physical impacts in an ideal way. The applicability of this method will be verified on an experimental high-rise building at the University campus in Stuttgart. Thus, this paper describes this innovative research project and depicts the concept of adaptivity in high-rise structures. Furthermore, it gives an overview of potential actuation concepts and the interdisciplinary challenges behind them.

• International Journal of Computer Science & Network Security
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• 제22권12호
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• pp.71-78
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• 2022

Electronic measuring devices have an important role in agricultural projects and in various fields. Electronic measuring devices play a vital role in controlling and saving soil information. They are designed to measure the temperature, acidity and moisture of the soil. In this paper, a new methodology to manage irrigation and soil fertility using an electronic system is proposed. This is designed to operate the electronic irrigation and adds inorganic fertilizers automatically. This paper also explains the concept of remote management and control of agricultural projects using electronic soil measurement devices. The proposed methodology is aimed at managing the electronic irrigation process, reading the moisture percentage, elements of soil and controlling the addition of inorganic fertilizers. The system also helps in sending alert messages to the user when an error occurs in measuring the percentage of soil moisture specified for crop and a warning message when change happens to the fertility of soil as many workers find difficulty in daily checking of soil and operating agricultural machines such as irrigation machine and soil fertilizing machine, especially in large projects.

• 한류연구
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• 제3권1호
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• pp.7-13
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• 2024

The study aims to examine the development of the South Korean music industry over time in order to capture the evolution process of the industry from its initial stages to its current state as one of the world's leading music markets. Based on the above consideration, a systematic literature review was conducted in order to provide an overview of the achievements of the South Korean music industry with the help of PRISMA method. The reason for doing this is to ensure that the process of selecting, filtering and collecting literature from different sources is not only efficient and time-saving but also rigid and coherent. This paper will explore the various elements that have defined the industry, including culture, technology, marketing and government policies and regulations (Jang & Song, 2017). Furthermore, it will inquire the effects of the K-pop cultural export on other industries, whether it be tourism, fashion, consumer goods, and more, thereby illustrating its vast significance. In more detail, this study aims to give an adequate idea about the historical accomplishments of the South Korean music industry in the global music map, identify factors that facilitated the enhancement of the industry and examine the significance of the findings and their applications for the industry's progression and development in the future.

• 대한예방한의학회지
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• 제19권2호
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• pp.103-112
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• 2015

Objective : To evaluate the status of mobile personal health records (mPHR) applications of Atopic Dermatitis, assessing general characteristics, information content, features of PHR content and functions. Method : Searches were conducted from Android's Google Play and iOS's App Store. Main criteria used to include mPHRs were: providing health information of PHR function of Atopic Dermatitis; operating in Korean or English; for human. Selected mPHRs were analyzed considering general characteristics, information contents, data elements, and application features. Results : 19 applications were included in this study. 15 were providing health information. Data elements of information included general information, symptom, diagnosis, treatment, prevention, management and FAQ. No single application contained all seven data elements. Only Eight applications had PHR function. In the features analysis, one PHR applications contained all eight PHR functional features; saving profile function, profiles supported, password, import data, export data, information provided, progress chart and push-up alarm. Conclusion : mPHR is an emerging health care technology. The majority of existing mPHR applications only provide one-way information. Application designed to help users and doctors to exchange mutual information was the only one. Also, there was no application that can record the Traditional Korean Medicinal treatment information. However, as the mobile market continues to expand it is likely that more comprehensive mPHRs will be developed in the near future. New advancements in mobile technology can be utilized to enhance Tranditional Korean Medical health care.