• The Journal of the Korea Contents Association
• /
• v.22 no.2
• /
• pp.35-43
• /
• 2022

The 2020 Gwangju Media Art Festival (2020 GMAF) was held in the area of the National Asian Cultural Center. Under the slogan "The entire Gwangju shines under the theme of "Aesthetics of Light and Coexistence," the media festival demonstrated projection mapping to Jeonnam (former) Provincial Office at the DATA+ Research Institute of Chung-Ang University's Graduate School of Advanced Video. This paper focuses on explaining the overall production process and content development of projection mapping demonstrated in the Jeollanam-do Provincial Government, which is a symbol of Korean democratization and is located in the center of Gwangju, Jeolla-do. It was intended to faithfully express the history of the 2020 GMAF and Jeonnam (former) provincial government, Gwangju's history, and democratization records. It was intended to show images, background sounds, sound effects, and visual effects using various special effects and high-power laser devices using unique characteristics of projection mapping. To this end, about 5 minutes and 30 seconds of content were planned, and it was divided into parts and topics, and one individual story was developed for each chapter.

• Journal of the Korea Society of Computer and Information
• /
• v.27 no.6
• /
• pp.117-122
• /
• 2022

In this paper, we developed a vehicle control terminal using IoT and low-power long-distance communication (NB-IoT) technology. This system collects information on the location and status of a parked vehicle, and transmits the vehicle status to the vehicle owner's terminal in real time with low power to prevent vehicle theft, and in the case of a vehicle in motion, When primary information about the vehicle, such as an impact, is collected and transmitted to the server, the server analyzes the relevant data to generate secondary information on traffic congestion, road damage, and safety accidents. By sending it, you can know the exact arrival time of the vehicle at its destination. This terminal device is an IoT gateway for a vehicle and can be connected to various wired and wireless sensors inside the vehicle. In addition, the data collected from vehicle maintenance, efficient operation, and vehicles can be usefully used in the private or public sector.

• Journal of the Korean Society of Propulsion Engineers
• /
• v.26 no.1
• /
• pp.1-11
• /
• 2022

In a gas turbine, fuel is exposed to a high temperature environment until it is fed to the combustor through the injector. Hydrocarbon fuels can coke under high temperature conditions, which can cause coking material to deposit on fuel lines or block the injector passages. In this study, a specimen simulating a fuel line located inside a gas turbine and Jet A-1 were heated using electric devices. Jet A-1 coking tests were performed by changing the wall temperature of the stainless steel specimen and the temperature of Jet A-1 supplied to the specimen. After the coked specimens were cut, the coking material and the inner surface were analyzed using an energy dispersive X-ray spectrometer and a field emission scanning electron microscope.

• The Journal of Korean Academy of Prosthodontics
• /
• v.61 no.1
• /
• pp.55-62
• /
• 2023

For fully edentulous patients, implant-supported overdenture can be considered to enhance chewing efficiency and denture stability. Implant planning software can be used to fabricate a surgical guide for a more precise consideration of anatomic factors and prediction of the shape of definitive prosthesis. Though there are many possible attachments for implant overdenture, milled bar can be useful due to its splinting effect of implants and rigid support of overdenture. This report presents a case of implant-supported milled bar overdenture after guided implant surgery performed with two surgical guide that was fabricated before and after bone reduction.

• Proceedings of the IEEK Conference
• /
• 1998.06a
• /
• pp.54-57
• /
• 1998

As the physical layer on telecommunication network is replaced fiber optic lines, it is increased the need of systematic maintenance for fiber optic lines. Korea Telecom has developed FLOMS in order to establish maintenance processes for optical fiber lines. FLOMS has functions which manages optical facilities and tests optical fiber lines automatically. As a resuls, this system can check and/or report a fault. Operator, who is reponsible for management of optical fiber lines, can test the characteristics of optical fiber lines remotely using FLOMS. As interpoerable with Digital Transmission Management System, FLOMS provides efficient management for optical fiber lines. This system improves the work process to find fault location fast, detect the degradation of fiber quality, and make database of optical facilities efficiently.

• Proceedings of the Korea Water Resources Association Conference
• /
• 2023.05a
• /
• pp.85-85
• /
• 2023

유량 측정을 위해 도섭법, 횡측선법 등의 인력에 의한 방법이 적용되고 있으나, 이는 야간 및 휴일 측정, 인력 부족 등 여러 제약으로 인해 고수위 홍수를 측정하는 데에 한계가 있다. 이를 해결하기 위해 시공간적 제약이 없는 도플러 방식 초음파유속계(Acousitc Doppler Velocity Meter, ADVM)와 자동유속관측시스템(Portable Automatic Velocity Observation System; PAVOs)이 제안되었다. 이 방법들은 교량에 설치된 장치를 통해 실시간으로 유속이 계측되어 시공간적 제약이 없으며 홍수 관리에 유용하게 사용될 수 있다. 실시간으로 계측된 유속 데이터는 오·결측 값이 발생하며 ADVM의 경우 수위-유량관계식을 활용하는 등 전처리 방법이 활용되고 있지만 전자파표면유속계를 활용한 PAVOs 데이터의 전처리 방법에 대한 연구는 부족하다. 따라서 본 연구에서는 PAVOs에서 실시간으로 계측된 유속 데이터의 전 처리 과정(Pre-processing)을 개발하였다. PAVOs를 통해 측정된 데이터는 5분 단위로 10개의 유속이 한번에 측정되며 비정상성(Non-stationary)인 특징을 가진다. 이 데이터의 전처리 과정으로 오·결측값에 대한 처리 및 보간법 적용 이후 10개 값 중 실제 유속을 판단하고 잡음제거(Denoising)를 수행하였다. 이를 강원도 홍천강에 위치한 홍천교에서 계측된 유속 데이터에 적용하였다. 그 결과 데이터의 상승부와 하강부에서 일정한 경향성을 파악할 수 있다. 이 데이터를 통해 산정한 유량과 실측 기반의 평균유속과 관계를 통해 계산한 유량을 비교해 보았을 때 낮은 편차율을 가지는 것을 확인하였다. 전 처리 된 실시간 유속 데이터를 활용한다면 최고수위가 발생하였을 경우 홍수량을 산정할 수 있을 것이다. 또한, 강우 또는 하천 공사에 의해 변동하는 수위-유량관계곡선식을 실시간으로 개발할 수 있을 것이며 이는 효과적인 홍수관리에 큰 역할을 할 수 있을 것이다.

• Proceedings of the Korea Water Resources Association Conference
• /
• 2023.05a
• /
• pp.195-195
• /
• 2023

유기물오염은 호수와 하천에서 가장 흔히 나타나는 오염의 형태이다. 개발도상국에서는 하수처리시설이나 생활용수처리시설에서 유기물이 처리되지 않아 수중의 유기물함량이 증가하여 피해가 나타난다. 물환경보전법에 따라 유기물질을 측정하는 지표에는 BOD, COD, TOC가 있다. 그 중 BOD, COD 측정은 절차가 복잡하고 오래 걸리며, 생물분해가 불가능하거나 유독물질이 존재하는 유기물질인 경우에는 낮은 결과 또는 측정이 불가능하다. 이러한 이유로 환경부에서는 TOC중심관리로 전환되고 있다. 대부분의 수질항목 측정의 경우 현장시료를 채취하여 실험실에서 분석하는 수분석을 이용한다. 하지만 수분석의 경우 인력이 많이 투입되고 분석수가 한정적이며, 정교한 과학 장치를 갖춘 전문 실험실을 필요로 한다. 반면에 TOC는 짧은 시간 내에 측정이 가능하고, 안정적인 산화로 유기물질 총량을 정확하게 측정이 가능하다. 또한 위해성 물질을 발생시키지 않는 친환경적 방법이라 환경오염 감시에 많이 활용된다. 본 연구에서 분광측정기 중 하나인 S-CAN을 통해 하천의 TOC분석을 진행하였다. 대상지는 안동에 위치한 하천실험센터와 금호강 진천천으로 S-CAN측정과 채취한 시료의 수분석 결과를 비교하였다. 이를 통해 TOC측정 및 기기에 대한 정확도분석을 실시하였다. 본 연구를 통해 S-CAN을 활용한 TOC중심의 수질모니터링하여 수질의 특성을 탐구하고, TOC기초연구를 통한 유기물오염도 지표로서 해석할 수 있다. 수분석 자료를 활용한 정확도 비교를 통해 하천 TOC센서 측정 적용에 대한 기초자료 제공과 측정기기의 현장적용성을 판단 할 수 있다. TOC측정 및 분석을 통해 유기물질량을 실시간으로 정확하게 측정하게 되면 수질관리 효율성이 높아지고, 하천에 유입되는 유기물질량과 농도를 정확하게 파악하여 실효성 있는 정책 수립 및 효율적인 수질관리를 할 수 있다.

• Journal of IKEEE
• /
• v.27 no.3
• /
• pp.225-233
• /
• 2023

This paper implements a system that monitors human body lifting information in the event of a marine accident. The monitoring system performs ultrasonic communication through a lifting device controller that transmits underwater environment information, and LoRa communication is performed on the water to provide GPS information within 10 km to the control center or mother ship. The underwater lifting controller transmits pneumatic sensor, gyro sensor, and temperature sensor information. In an environment where the underwater conditions increase by one atmosphere of water pressure every 10m in depth, and the amount of air in the instrument decreases by half compared to land, a model of a 60kg underwater mannequin is used. Using one 38g CO2 cartridge in the lifting appliance SMB(Surface Maker Buoy), carry out a lifting appliance discharge test based on the water level rise conditions within 10 sec. Underwater communication constitutes a data transmission environment using a 2,400-bps ultrasonic sensor from a depth of 40m to 100m. The monitoring signal aims to ensure the safety and safe human structure of the salvage worker by providing water depth, water temperature, and directional angle to rescue workers on the surface of the water.

• Journal of Practical Agriculture & Fisheries Research
• /
• v.12 no.1
• /
• pp.29-38
• /
• 2010

This research was conducted to improve a hill seeding technology under puddled wet soil condition for direct seeded rice. There were severe constrains in hill sowing method under puddled wet soil such as a bird damages, dryness of seeds sown due to strong sunlight in May and buoyancy of seeds and young seedlings after raining and irrigation particular under strong wind. Thus, we have adopted a sandy type(<2mm) silicate covering method in Bokto drill seeding technology for a hill seeding method as well. The average silicate amount in order to cover seeds sown was of 840kg/ha which was evaluated to a proper volume for those problem solution and farmer's handling during sowing operation. In this experiment there was an additional problem like a precious hill drop of rice seeds, covering of silicate over hill seeded rice and seed broken during roller operation.

• The Journal of the Convergence on Culture Technology
• /
• v.9 no.1
• /
• pp.545-550
• /
• 2023

A pretensioner is a safety device that protects occupants by pulling the seat belt in the event of a vehicle collision. However, since the pretensioner is driven by a explosive method, it is necessary to replace not only the gas generator but also all connecting parts including the manifold after an accident. Therefore, in this paper, we propose an elastic force-based pretensioner that can be used safely and semi-permanently. After analyzing the operating mechanism of the existing pretensioner from a thermodynamic/dynamic point of view, the spring stiffness that can be deployed within an appropriate operating time was determined by converting the gas explosion energy into elastic energy. In addition, the coil spring shape that satisfies the elastic stiffness was designed in consideration of the vehicle interior installation standard. Finally, the operating performance of the pretensioner driven by elastic force was verified through fabrication.