• Title/Summary/Keyword: Sensors

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Development of Environmental Safety Real-Time Monitoring System by Living Area (생활권역별 환경안전 실시간 모니터링 시스템의 개발)

  • Lee, Joo-Hyun;Kim, Joo-Ho;Lee, Seung-Ho
    • Journal of IKEEE
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    • v.23 no.3
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    • pp.1088-1091
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    • 2019
  • In this paper, a real-time monitoring system for environmental safety by living area is proposed. The proposed system is designed to measure radiation, fine dust and basic living information (temperature) using fixed and mobile measuring equipment, and constitutes a web database that stores data received from the equipment. It also develops web programs for displaying received data on PCs and mobile phones. The results of testing the performance of the system by an authorized testing agency showed that the radiation measurement range was measured in the range of $10{\mu}Sv/h$ to 10mSv/h, which is comparable to the world's highest level, and that the accuracy was measured between ${\pm}6.7$ and ${\pm}8.7$ percent of the measurement uncertainty was measured and normal operation at or below the international standard of ${\pm}15$ percent. In addition, the temperature test was conducted on a section of $-20^{\circ}C$ to $50^{\circ}C$ and normal operation was confirmed in response to the temperature change. Stability of radiated electromagnetic waves was ensured by a suitable judgment. The product's testing in general and high and low temperature environments for about four months after the prototype was made confirmed to be more than five years of durability. The measurement range and accuracy of fine dust sensors are compared with those of companies that measure the air environment, and the performance level is similar through the air quality measurement register.

Analysis of acoustic emission parameters according to failure of rock specimens (암석시편 파괴에 따른 acoustic emission 특성인자 분석)

  • Lee, Jong-Won;Oh, Tae-Min;Kim, Hyunwoo;Kim, Min-Jun;Song, Ki-Il
    • Journal of Korean Tunnelling and Underground Space Association
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    • v.21 no.5
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    • pp.657-673
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    • 2019
  • A monitoring method based on acoustic emission (AE) sensor has been widely used to evaluate the damage of structures in underground rock. The acoustic emission signal generated from cracking in material is analyzed as various acoustic emission parameters in time and frequency domain. To investigate from initial crack generation to final failure of rock material, it is important to understand the characteristics of acoustic emission parameters according to the stress ratio and rock strength. In this study, uniaxial compression tests were performed using very strong and weak rock specimen in order to investigate the acoustic emission parameters when the failure of specimen occurred. In the results of experimental tests, the event, root-mean-square (RMS) voltage, amplitude, and absolute energy of very strong rock specimen were larger than those of the weak rock specimen with an increase of stress ratio. In addition, the acoustic emission parameters related in frequency were more affected by specification (e.g., operation and resonant frequency) of sensors than the stress ratio or rock strength. It is expected that this study may be meaningful for evaluating the damage of underground rock when the health monitoring based on the acoustic emission technique will be performed.

A Study on HCI Design based on Tactical Data Link integrated in KDDX Combat Management System for Korean-Type Mobile Fleet Control (차기구축함 전투관리체계에 통합된 전술데이터링크 기반의 한국형 기동함대 통제 HCI 설계에 관한 연구)

  • Song, Ha-Seok
    • The Journal of Korea Institute of Information, Electronics, and Communication Technology
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    • v.12 no.5
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    • pp.482-492
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    • 2019
  • The naval ship consists of a variety of classes, including patrol, frigate, destroyer and landing ship. There are various means of communication between combat ships belonging to the mobile fleet, including voice network, text message network and tactical data link. The operation at the existing mobile fleet level was conducted mainly on voice and text message, and tactical data link were used mainly to share tactical information between combat ships. This study intended to design HCI for commander like as KDDX of fleet level based on tactical data link, a means of communication between ships, to secure operational control of the mobile fleet. Recently, naval ships have been developed in the organization of various sensors, weapons and tactical data links integrated into the combat management system, and this study also designed the HCI based on the tactical data links integrated in the combat management system. The purpose of this study was to secure the operational efficiency of the tactical data link based on the combat management system in operation of the mobile fleet, and to improve the capability of the fleet commander to recognize the battlefield situation awareness.

A Secure and Lightweight Authentication Scheme for Ambient Assisted Living Systems (전천 후 생활보조 시스템을 위한 안전하고 경량화 된 인증기법)

  • Yi, Myung-Kyu;Choi, Hyunchul;Whangbo, Taeg-Keun
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.19 no.4
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    • pp.77-83
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    • 2019
  • With the increase in population, the number of such senior citizens is increasing day by day. These senior citizens have a variety of care needs, but there are not enough health workers to look after them. Ambient Assisted Living (AAL) aims at ensuring the safety and health quality of the older adults and extending the number of years the senior citizens can live independently in an environment of their own preference. AAL provides a system comprising of smart devices, medical sensors, wireless networks, computer and software applications for healthcare monitoring. AAL can be used for various purposes like preventing, curing, and improving wellness and health conditions of older adults. While information security and privacy are critical to providing assurance that users of AAL systems are protected, few studies take into account this feature. In this paper, we propose a secure and lightweight authentication scheme for the AAL systems. The proposed authentication scheme not only supports several important security requirements needed by the AAL systems, but can also withstand various types of attacks. Also, the security analysis results are presented to show the proposed authentication scheme is more secure and efficient rather than existing authentication schemes.

High temperature electrical properties of Sr-and Mg-Doped LaAlO3 (억셉터(Sr, Mg)가 첨가된 LaAlO3의 고온 전도 특성)

  • Park, Ji Young;Park, Hee Jung
    • Journal of the Korean Crystal Growth and Crystal Technology
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    • v.29 no.5
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    • pp.187-191
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    • 2019
  • Perovskite-type oxides have consistently attracted considerable attention for their applications in high-temperature electrochemical devices, such as electrolytes and electrodes of solid oxide fuel cells, oxygen permeating membranes and sensors etc. Among them, the electrical conductivity of 10 % Sr and 10 % Mg doped $LaAlO_3$ (LSAM9191) was measured using impedance spectroscopy and 4-probe d.c. method. Below $550^{\circ}C$, the grain boundary resistance mostly determined the overall conductivity; however, it nearly disappeared above $800^{\circ}C$. Using the defect model and curve fitting, the ionic and electronic conductivity contributions were also separated. In the temperature region where the sample resistance is mostly determined by the grain volume property, LSAM9191 was an oxygen ion conductor at low $Po_2$ and a mixed conductor at high $Po_2$. With increasing temperature, the ionic conduction region only slightly increased. Thus, LSAM9191 is a promising material as an oxygen ion conductor at high temperature and in low $Po_2$.

The Future Direction of HD Map Industry Development Plan and Governance (정밀도로지도 산업 발전 방향 및 대응방안 연구)

  • WON, Sang-Yeon;MOON, Ji-Young;YOON, Seo-Youn;CHOI, Yun-Soo
    • Journal of the Korean Association of Geographic Information Studies
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    • v.22 no.3
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    • pp.120-132
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    • 2019
  • As a key infrastructure for positioning autonomous vehicles, HD maps are making efforts to equip autonomous vehicles and connect them with services worldwide. Global companies like Here and TomTom have contracted an agreement with three German automobile companies(BMW, Audi, Daimler) by establishing systems including from the production of HD maps to loading autonomous vehicles. Japan has organized a DMP(Dynamic Map Platform) by collaborating public and private section and performing establishment of HD map on private section-oriented. Korean companies related with autonomous vehicles are also cooperating with various companies such as vehicles, sensors and maps. But public and private sections are establishing HD maps respectively. Accordingly, Ministry of Land, Infrastructure and Transport implemented and signed memorandum for private and public cooperation in April 2019, Joint establishment council of HD map has launched in August 2019. This study performed domestic and foreign trend analysis about HD map and interviewed to related companies. And analyzed solutions for interactive cooperation of private and public section in HD map industry, purposed step-by-step strategy for operation and operation plan for joint establishment council of HD map.

A Study on the Improvement of Disaster and Safety Management for Local Cultural Heritages (지방문화재 재난안전관리 개선방안에 관한 연구)

  • Kim, Twe-Hwan;Kim, Jung-Gon;Been, Ju-Hee
    • Journal of the Society of Disaster Information
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    • v.15 no.3
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    • pp.358-366
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    • 2019
  • Purpose: This paper aims to clarify the problems and to examine the improvement methods by investigating the management condition of local-designated cultural property of which management is relatively poor in comparison with state-designated cultural heritage. Method: In order to grasp the management situation of the local-designated cultural heritage, a research on cultural heritage management situation and problems will be carried out with 35 cultual heritages in Goryeong-gun. Also, the improvement methods about the property type vulnerability on the basis of interview with cultual property managers, fire-fighting officers and civil servants, etc. Results: Local cultural heritages were investigated to be very vulnerable to the fire of wooden buildings, the theft of movable cultural heritages, and the effects of wind and water damage. It is because cultural heritages are scattered over wide areas fundamentally. As the result, it has difficulty in the patrols of police officers and fire fighters, and in the situation that it lacks disaster monitoring and CCTV for countermeasures to replace them, electronic security including fire hydrant, sensors, etc and fire extinguishing facilities and so on. It is difficult for local governments managing local-designated cultural heritages to enhance their management systems directly due to their lack of budget and manpower. Conclusion: In order to strengthen disaster and safety management system for the cultural heritages designated by local governments, they have to clarify disaster countermeasure task of fire fighting, police, and cultural heritage managers prepare their manuals, and systematize them through disaster drill mainly in local autonomous governments. Also, so as to establish a surveillance system every day, they have to enhance the community for local cultural heritage manage consisting of local volunteer fire departments, local voluntary disaster prevention organizations, volunteers, etc.

Effect of Temperature on Growth of Tin Oxide Nanostructures (산화주석 나노구조물의 성장에서 기판 온도의 효과)

  • Kim, Mee-Ree;Kim, Ki-Chul
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.20 no.4
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    • pp.497-502
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    • 2019
  • Metal oxide nanostructures are promising materials for advanced applications, such as high sensitive gas sensors, and high capacitance lithium-ion batteries. In this study, tin oxide (SnO) nanostructures were grown on a Si wafer substrate using a two-zone horizontal furnace system for a various substrate temperatures. The raw material of tin dioxide ($SnO_2$) powder was vaporized at $1070^{\circ}C$ in an alumina crucible. High purity Ar gas, as a carrier gas, was flown with a flow rate of 1000 standard cubic centimeters per minute. The SnO nanostructures were grown on a Si substrate at $350{\sim}450^{\circ}C$ under 545 Pa for 30 minutes. The surface morphology of the as-grown SnO nanostructures on Si substrate was characterized by field-emission scanning electron microscopy (FE-SEM) and atomic force microscopy (AFM). Raman spectroscopy was used to confirm the phase of the as-grown SnO nanostructures. As the results, the as-grown tin oxide nanostructures exhibited a pure tin monoxide phase. As the substrate temperature was increased from $350^{\circ}C$ to $424^{\circ}C$, the thickness and grain size of the SnO nanostructures were increased. The SnO nanostructures grown at $450^{\circ}C$ exhibited complex polycrystalline structures, whereas the SnO nanostructures grown at $350^{\circ}C$ to $424^{\circ}C$ exhibited simple grain structures parallel to the substrate.

Fabrication of Poly(methyl methacrylate) Beads Monolayer Using Rod-coater and Effects of Solvents, Surfactants and Plasma Treatment on Monolayer Structure (Rod 코팅을 이용한 Poly(methyl methacrylate) 비드의 단일층 형성 및 단일층 구조에 미치는 용매, 계면활성제, 플라즈마 처리의 영향)

  • Kim, Da Hye;Ham, Dong Seok;Lee, Jae-Heung;Huh, Kang Moo;Cho, Seong-Keun
    • Journal of Adhesion and Interface
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    • v.20 no.1
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    • pp.1-8
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    • 2019
  • Fabrication of monolayer is important method for enhancing physical and chemical characteristics such as light shielding and antireflection while maintaining thin film properties. In previous studies, monolayers were fabricated by various methods on small substrates, but processes were complicated and difficult to form monolayers with large area. We used rod coating equipment with a small amount of coating liquid to form a HCP (hexagonal closed packing) coating of PMMA beads on PET(poly(ethylene terephthalate)) substrate with $20cm{\times}20cm$ size. We observed that changes in morphologies of monolayers by using the solvents with different boiling points and vapor pressures, by adapting surfactants on particles and by applying plasma treatment on substrates. The coverage was increased by 20% by optimizing the coating conditions including meniscus of beads, control of the attraction - repulsion forces and surface energy. This result can potentially be applied to optical films and sensors because it is possible to make a uniform and large-scale monolayer in a simple and rapid manner when it is compared to the methods in previous studies.

Design and Implementation of Fruit harvest time Predicting System based on Machine Learning (머신러닝 적용 과일 수확시기 예측시스템 설계 및 구현)

  • Oh, Jung Won;Kim, Hangkon;Kim, Il-Tae
    • Smart Media Journal
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    • v.8 no.1
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    • pp.74-81
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    • 2019
  • Recently, machine learning technology has had a significant impact on society, particularly in the medical, manufacturing, marketing, finance, broadcasting, and agricultural aspects of human lives. In this paper, we study how to apply machine learning techniques to foods, which have the greatest influence on the human survival. In the field of Smart Farm, which integrates the Internet of Things (IoT) technology into agriculture, we focus on optimizing the crop growth environment by monitoring the growth environment in real time. KT Smart Farm Solution 2.0 has adopted machine learning to optimize temperature and humidity in the greenhouse. Most existing smart farm businesses mainly focus on controlling the growth environment and improving productivity. On the other hand, in this study, we are studying how to apply machine learning with respect to harvest time so that we will be able to harvest fruits of the highest quality and ship them at an excellent cost. In order to apply machine learning techniques to the field of smart farms, it is important to acquire abundant voluminous data. Therefore, to apply accurate machine learning technology, it is necessary to continuously collect large data. Therefore, the color, value, internal temperature, and moisture of greenhouse-grown fruits are collected and secured in real time using color, weight, and temperature/humidity sensors. The proposed FPSML provides an architecture that can be used repeatedly for a similar fruit crop. It allows for a more accurate harvest time as massive data is accumulated continuously.