• 한국산업융합학회 논문집
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• 제24권4_1호
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• pp.397-409
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• 2021

This study proposes a new approach to implimentation of robust control and torque control response analysis based on monitoring simulator for smart factory. According to the physical properties of a flexible manipulator, a two time-scale approach, namely, singular perturbation ap proach, is further utilized for thorough analysis and general controller design. It is shown that asymptotic motional tracking can be effectively achieved, whereas the force regulation errors can be made arbitrarily small. For demonstration of the proposed technology performance, experiments of a eight joint flexible manipulator are performed for the proposed control method, and the reliability of proposed control results are illustrated based on monitoring simulator.

• 한국보육지원학회지
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• 제17권3호
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• pp.65-87
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• 2021

Objective: This study aimed to examine the effects of maternal monitoring, shared activities with children, maternal education-oriented behavior, and allowing children to own smart-phones on smart media usage patterns based on smart-phone usage time and purposes among elementary school children. Methods: The participants were 1,315 second-grade elementary school children from the 9th wave of PSKC. Latent profile analysis and the three-step estimation approach were used to examine the determinants of the latent profile and the effects of maternal parenting on the profile. Results: Four latent profiles were identified: 'High-level usage & Entertaining oriented,' 'Moderate-level usage & Social/entertaining oriented,' 'Moderate-level usage & Learning oriented,' and 'Low-level usage.' Additionally, results showed that each profile can be predicted by maternal monitoring, education-oriented behavior, and permitting children to own smart-phones. Conclusion/Implications: Our outcomes suggested that it would be necessary to understand the smart media usage patterns of elementary school children, considering both the amount of time spent with smart media and purposes of uses. Further, it is helpful for mothers to monitor children's daily activities, support their educational activities, and take the role of gatekeeper for smart media as a way of appropriate guidance for their children's use of smart media.

• 한국구조물진단유지관리공학회 논문집
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• 제9권4호
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• pp.227-234
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• 2005

본 논문에서는 토목구조물의 스마트 모니터링 시스템을 위한 MEMS 형식의 가속도 센서를 부착한 스마트 무선 센서 장치를 설계하고 제작하였다. 그리고 다양한 성능 실험을 통하여 장치의 성능을 평가하였다. 첫째 장치에 부착한 가속도 센서의 민감도와 분해능, 잡음을 평가하기 위한 실험을 실시하였다. 실험의 결과는 센서의 데이터 쉬트의 값과 비교하여 센서의 성능을 평가 하였다. 두 번째로는 무선 센서 장치를 이용하여 상시 가진을 받는 모형구조물의 동특성을 NExT와 ERA 알고리즘을 사용하여 분석하였다. 이와 같이 분석된 동적 특성은 유한요소 해석 결과와 상호 비교하여 그 유용성을 입증하였고, 스마트 모니터링 시스템에 무선 센서 장치가 효과적으로 적용될 수 있는 가능성을 제시하였다.

• 한국CDE학회논문집
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• 제19권2호
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• pp.169-181
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• 2014

Recently ships and ocean platforms are becoming increasingly technological, unmanned, and huge. Maintenance and safety monitoring of these products is very important for safety reasons. Therefore, real-time monitoring of safety regions, such as the engine room, and hull structure, and environmental states, like fire and pressure of LNG tanks, is required for the sustainable ships. In this paper, a ZigBee-based wireless sensor network is suggested to monitor ships and ocean platforms effectively. However, this causes some telecommunication problems because these products are made of steel. To resolve this problem, we use the mesh networking of Zig-Bee that can monitor the regions and environmental states consistently. The telecommunication of such a monitoring system is tested on a real container ship and its performance is verified. The real-time monitoring results are displayed on the users' smart devices.

• Smart Structures and Systems
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• 제5권4호
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• pp.381-395
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• 2009

The paper presents a case study in which the structural condition assessment of the East Bay bridge in Gibsonton, Florida is evaluated with the help of remote health monitoring techniques. The bridge is a four-span, continuous, deck-type reinforced concrete structure supported on prestressed pile bents, and is instrumented with smart Fiber Optic Sensors. The sensors used for remote health monitoring are the newly emerged Fabry-Perot (FP), and are both surface-mounted and embedded in the deck. The sensing system can be accessed remotely through fast Digital Subscriber Lines (DSL), which permits the evaluation of the bridge behavior under live traffic loads. The bridge was open to traffic since March 2005, and the collected structural data have been continuously analyzed since. The data revealed an increase in strain readings, which suggests a progression in damage. Recent visual observations also indicated the presence of longitudinal cracks along the bridge length. After the formation of these cracks, the sensors readings were analyzed and used to extrapolate the values of the maximum stresses at the crack location. The data obtained were also compared to initial design values of the bridge under factored gravity and live loads. The study showed that the proposed structural health monitoring technique proved to provide an efficient mean for condition assessment of bridge structures providing it is implemented and analyzed with care.

• 한국정보통신학회:학술대회논문집
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• 한국정보통신학회 2017년도 춘계학술대회
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• pp.503-504
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• 2017

최근 세계 각국의 경제적 성장과 함께 건강한 삶에 대한 관심이 증가하고 있으며, 이에 따른 스마트헬스케어 산업이 활성화 되고 있다. 스마트헬스케어 분야에서는 IoT기술의 부각에 따라 웨어러블 형태의 생체정보 계측기술이 부각되고 있다. 본 연구에서는 웨어러블 헬스케어에 응용이 가능하고 활동 중에도 편리하게 심박동의 모니터링을 수행 할 수 있는 장갑형태의 착용형 심박동 모니터링시스템을 구현하고자 하였다. 이를 위해 손가락 말초에서의 혈류량변화를 모니터링하고 디스플레이 할 수 있는 장갑형 웨어러블 헬스케어시스템을 제작하고 그 성능평가를 수행하였다. 실험결과 실제 일상생활 중 움직임을 수반하더라도 심박동의 모니터링이 가능함을 확인할 수 있었다.

• 한국인터넷방송통신학회논문지
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• 제12권5호
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• pp.261-265
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• 2012

현재 증강현실 기술은 IT융합을 통해 여러 가지 분야의 응용서비스로서 활용가치가 점점 늘어나고 있으며, 스마트디바이스에서도 증강현실기술과 융합된 App을 쉽게 찾아볼 수 있다. 때문에 증강현실 기술을 광고나 전시회, 공연 같은 곳에서 활용하려는 시도는 활성화 되었지만, 아직 다른 분야의 증강현실 기술보다는 상대적으로 전문성이 떨어지며, 그중 환경모니터링과 연동되어 사용되는 서비스는 부족한 현실이다. 이에 본 논문에서는 이미 많은 지역에 광고홍보물의 목적으로 구축되어 있는 QR코드를 증강현실 기술과 접목하여 무인빌딩이나 자동화설비장과 같은 산업적으로 활용될 수 있는 QR코드와 환경감시센서를 활용한 스마트 디바이스기반 증강현실형 모니터링 기술을 제안하고자 한다.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2007년도 춘계학술대회논문집
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• pp.448-452
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• 2007

Many industrial operations require continuous or nearly-continuous operation of machines, which if interrupted can result in significant financial loss. The condition monitoring of these machines has received considerable attention recent years. Rapid developments in semiconductor, computing, and communication with a remote site have led to a new generation of sensor called "smart" sensors which are capable of wireless communication with a remote site. The purpose of this research is the development of smart sensor using which can on-line perform condition monitoring. This system is addressed to detect conditions that may lead to equipment failure when it is running. Moreover it will reduce condition monitoring expense using low cost MEMS accelerometer. This sensor can receive data in real-time or periodic time from MEMS accelerometer. Furthermore, this system is capable for signal preprocessing task (High Pass Filter, Low Pass Filter and Gain Amplifier) and analog to digital converter (A/D) which is controlled by CPU. A/D converter that converts 10bit digital data is used. This sensor communicates with a remote site PC using TCP/IP protocols. Wireless LAN contain IEEE 802.11i-PSK or WPA (PSK, TKIP) encryption. Developed sensor executes performance tests for data acquisition accuracy estimations.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 학술대회 논문집 정보 및 제어부문
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• pp.264-266
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• 2005

Recently, on-line diagnosis methods through wired and wireless networks are widely adopted in the diagnosis of industrial Electric Facilities, such as generators, transformers and motors. Also smart sensors which includes sensors, signal conditioning circuits and micro-controller in one board are widely studied in the field of condition monitoring. This paper suggests an self-powered system suitable for condition-monitoring smart sensors, which uses parasitic vibrations of the facilities as energy source. First, vibration-driven noise patterns of the electric facilities are presented. And then, an electromagnetic generator which uses mechanical mass-spring vibration resonance are suggested and designed. Finally energy consumption of the presented smart sensor, which consists of MEMS vibration sensors, signal conditioning circuits, a low-power consumption micro-controller, and a ZIGBEE wireless tranceiver, are presented. The usefulness and limits of the presented electromagnetic generators in the field of electric facility monitoring are also suggested.

• Smart Structures and Systems
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• 제6권3호
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• pp.309-333
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• 2010

Civil infrastructure, in both its construction and maintenance, represents the largest societal investment in this country, outside of the health care industry. Despite being the lifeline of US commerce, civil infrastructure has scarcely benefited from the latest sensor technological advances. Our future should focus on harnessing these technologies to enhance the robustness, longevity and economic viability of this vast, societal investment, in light of inherent uncertainties and their exposure to service and even extreme loadings. One of the principal means of insuring the robustness and longevity of infrastructure is to strategically deploy smart sensors in them. Therefore, the objective is to develop novel, durable, smart sensors that are especially applicable to major infrastructure and the facilities to validate their reliability and long-term functionality. In some cases, this implies the development of new sensing elements themselves, while in other cases involves innovative packaging and use of existing sensor technologies. In either case, a parallel focus will be the integration and networking of these smart sensing elements for reliable data acquisition, transmission, and fusion, within a decision-making framework targeting efficient management and maintenance of infrastructure systems. In this paper, prudent and viable sensor and health monitoring technologies have been developed and used in several large structural systems. Discussion will also include several practical bridge health monitoring applications including their design, construction, and operation of the systems.