• 사물인터넷융복합논문지
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• 제10권2호
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• pp.103-108
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• 2024

본 논문에서는 YOLO(You only look once)v5를 기반으로 한 실시간 객체 검출 기술을 활용하여 스마트 엘리베이터 시스템을 연구하였다. 외부 엘리베이터 버튼이 눌러지면 YOLOv5 모델이 카메라 영상을 분석하여 대기자의 유무를 판별하고, 대기자가 없다고 판별되면 해당 버튼을 자동으로 취소시킨다. 연구에서는 YOLOv5와 사물인터넷에서 활용되는 MQTT(Message Queuing Telemetry Transport)를 통한 객체 탐지 및 통신 기술의 효과적인 구현 방법을 소개한다. 그리고 이를 활용하여 대기자 유무를 실시간으로 판별하는 스마트 엘리베이터 시스템을 구현하였다. 제안한 시스템은 불필요한 소비 전력을 절감하면서 CCTV(closed-circuit television)의 역할을 할 수 있다. 따라서 제안한 스마트 엘리베이터 시스템은 안전 및 치안 문제에도 기여할 수 있을 것으로 기대한다.

• 전자공학회논문지
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• 제53권9호
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• pp.3-11
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• 2016

향상된 무선 통신 시스템을 이용하여 교통안전을 개선하기 위해 V2X (Vehicle to Everything) 통신에 대한 연구가 활발히 진행되고 있다. V2X 통신은 미래 교통안전 및 이동성의 발전을 위한 하나의 주요 솔루션이다. 본 논문에서는 LTE (Long Term Evolution) 기반 V2X 시스템 레벨 시뮬레이터 (SLS : System Level Simulator)를 개발하고 차량통신을 위한 적응적 전송 기법을 제안한다. 제안 기법은 시간 및 주파수 영역에서 랜덤하게 자원을 할당하고 전송 확률에 따라 메시지 전송을 결정한다. 성능 분석은 주기적 메시지 전송에서 고속도로의 경우에 대하여 이루어 졌다. 모의실험 결과, 제안한 기법에서 자원 충돌 및 간섭이 감소함 따라 PRR (Packet Reception Ratio)의 CDF (Cumulative Distribution Function) 및 평균 PRR이 향상 되는 것을 볼 수 있다.

• 한국ITS학회 논문지
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• 제11권6호
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• pp.103-110
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• 2012

VANET의 대표적 응용인 차량 안전 통신에서는 차량 운행 중 긴급 상황에 대처하기 위하여 차량 간 통신을 통해서 EWM (Emergency Warning Message)을 브로드캐스트하게 된다. 그러나 차량의 수가 증가하게 되면 다수의 중복된 EWM의 송수신으로 인하여 Broadcast Storm Problem이 발생한다. Broadcast Storm Problem을 해결하기 위한 여러 가지 방안들이 제시되었으나 대부분의 경우, 사전에 주변 차량들과의 주기적인 Beacon 메시지의 송수신을 통하여 이웃관계를 설정하거나 이동성에 따른 토폴로지 변화로 이웃관계를 재설정해야 하는 과정이 필요하며 동시에 Beacon 메시지 교환에 따라 통신부하를 가중시키게 된다. 본 논문에서는 이웃관계 설정을 위한 Beacon 메시지 교환과정을 생략하고 Broadcast Storm Problem을 효율적으로 해결할 수 있는 LLR (Longest Leaping Relay) 기법을 제안하여 컴퓨터 시뮬레이션을 통해 성능을 검증하였다.

• 한국안전학회지
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• 제30권1호
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• pp.14-20
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• 2015

A Large Eddy Simulation(LES) was performed for the prediction of unsteady dispersion behavior of hydrogen fluoride (HF). The HF leakage accident occurred at the Gumi fourth industrial complex was numerically investigated using the Fire Dynamics Simulator (FDS) based on the LES. The accident area was modeled three-dimensionally and time-varying boundary conditions for wind were adopted in the simulation for considering the realistic accident conditions. The Message Passing Interface (MPI) parallel computation technique was used to reduce the computational time. As a result, it was found that the present LES simulation could predict the unsteady dispersion features of HF near the accident area effectively. The dispersion behaviors of the leaked HF was much affected by the unsteady wind direction. The LES could predict the time variation of the HF concentration reasonably and give an useful information for the risk analysis while the prediction with the time-averaging concept of HF concentration had a limitation for the amount of HF concentration at specific location point. It was identified that the LES is very useful to predict the dispersion characteristics of hazardous chemicals.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2007년도 춘계학술대회 논문집
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• pp.953-958
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• 2007

Passenger safety is a primary concern of railway system but, it has been urgent issue that dozens of people are killed every year when they are fallen from train platforms. In this paper, we propose a vision based monitoring system for railway station platform. The system immediately perceives dangerous factors of passengers on the platform by using image processing technology. To monitor almost entire length of the track line in the platform, we use several video cameras. Each camera conducts surveillance its own preset monitoring area whether human or dangerous object was fallen in the area. Moreover, to deal with the accident immediately, the system provides local station, central control room employees and train driver with the video information about the accident situation including alarm message. This paper introduces the system overview and detection process with experimental results. According to the results, we expect the proposed system will play a key role for establishing highly intelligent monitoring system in railway.

• 한국품질경영학회:학술대회논문집
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• 한국품질경영학회 2009년도 추계학술대회
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• pp.136-146
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• 2009

This performed a study for the warning indication method and to prevent "defect in expression" that could occur at a product use stage in this study. To accomplish this, companies can increase effectiveness in the warning process presented apply to products which have a direct warning methodology by looking at the combination of research has demonstrated. How to study the existing warning signs of improvement throughout the consumer's visibility, readability, increased availability understand this consumer satisfaction measurement results confirm the safety three years could find lasting satisfaction to rise.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2009년도 제40회 하계학술대회
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• pp.1183_1184
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• 2009

The synchronized visual message system device of level crossing provides warning system with the use of developed corresponding technology when the train is approaching forward to limited distance in level crossing. To ensure of safety driving for coming transit from road, it detect the location and velocity of train and transport the information to wayside warning device to prevent the collision with train. This paper is about the detailed design of synchronize VMS for passing transit at the level crossing and develop the physical contents of level crossing VMS with expression words, operational device, massage transportation algorism which are based on the proto type study of communication method and information contents for level crossing VMS.

• 한국정보통신학회논문지
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• 제6권6호
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• pp.863-872
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• 2002

Real-time(RT) object-oriented(00) distributed computing is a form of RT distributed computing realized with a distributed computer system structured in the form of an object network. Several approached proposed in recent years for extending the conventional object structuring scheme to suit RT applications, are briefly reviewed. Then the approach named the TMO(Time-triggered Message-triggered Object) structuring scheme was formulated with the goal of instigating a quantum productivity jump in the design of distributed time triggered simulation. The TMO scheme is intended to facilitate the pursuit of a new paradigm in designing distributed time triggered simulation which is to realize real-time computing with a common and general design style that does not alienate the main-stream computing industry and yet to allow system engineers to confidently produce certifiable distributed time triggered simulation for safety-critical applications. The TMO structuring scheme is a syntactically simple but semantically powerful extension of the conventional object structuring approached and as such, its support tools can be based on various well-established 00 programming languages such as C++ and on ubiquitous commercial RT operating system kernels. The Scheme enables a great reduction of the designers efforts in guaranteeing timely service capabilities of application systems.

• 한국IT서비스학회지
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• 제16권2호
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• pp.129-138
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• 2017

This paper is concerned with an Internet of Things (IoT)-based unmanned home-delivery box system, in which the system is developed with a prototype using a weight sensor, shock sensor, the Arduino and Raspberry-Pi of open-source hardware platforms. The developed system provides several functions such as a safe storage means, prevention of delivery-theft, and remote control of the home-delivery box, etc. Specifically, the system recognizes the arrival of goods by detecting the weight of deliveries and sends the arrived message of deliveries to the recipient' smartphone, and also controls (i.e., open and close) the locker of the unmanned home-delivery box system remotely with the smartphone. Furthermore, the developed system provides automatically a warning alarm around the unmanned home-delivery box when an external shock is applied to the home-delivery box, and sends a message on the shock to the recipient' smartphone. The major functions of the developed home-delivery box system have been verified in a realistic environment, and confirmed to work well. With the application of the developed home-delivery box system to the homes and offices where recipients are always not to stay, it is expected to significantly improve the safety of delivered goods as well as to effectively prevent the delivery operatives posing as a crime.

• 한국자동차공학회논문집
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• 제19권6호
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• pp.37-45
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• 2011

As vehicles become more intelligent, in-vehicle networking (IVN) systems such as controller area network (CAN) or FlexRay are essential for convenience and safety of drivers. To expand the applicability of IVN systems, attention is currently being focused on the communication between heterogeneous networks such as body networking and chassis networking systems. A gateway based on message mapping method was developed to interconnect FlexRay and CAN networks. However, this type of gateways has the following shortcomings. First, when a message ID was changed, the gateway must be reloaded with a new mapping table reflecting the change. Second, if the number of messages to be transferred between two networks increase, software complexity of gateway increases very rapidly. In order to overcome these disadvantages, this paper presents FlexRay-CAN gateway based on node mapping method. More specifically, this paper presents a node mapping based FlexRay-CAN gateway operation algorithm along with the experimental evaluation for ID change.