• 한국방송∙미디어공학회:학술대회논문집
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• 한국방송공학회 2011년도 추계학술대회
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• pp.180-183
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• 2011

최근 3D 입체영상에 대한 소비자들의 관심 증대로 가전 업체들은 3D TV, 3D Monitor등의 제품들을 출시하고 있고, 이에 따라 3D 콘텐츠 시장도 급격히 성장할 것으로 예상된다. 또한 네트워크 인프라의 발전으로 IP(Internet Protocol)망을 통한 고화질 동영상의 유통이 가능해졌다. 하지만, QoS(Quality of Service)를 보장하지 않는 IP 기반 전송환경에서의 고화질 미디어 스트리밍 서비스는 콘텐츠를 시청하는 소비자 관점에서 필수적으로 보장되어야 하는 끊김 없는 영상서비스를 제공하는데 제약이 있다. 이러한 문제를 해결하기 위해서, IP 망 네트워크 환경을 고려하여 사용자들이 원하는 콘텐츠를 고품질 혹은 저품질로 제공 할 수 있는 Adaptive 스트리밍 서비스에 관한 기술 개발이 등장하게 되었고, 현재 국제 표준화 기구인 MPEG(Moving Picture experts Group)에서 DASH(Dynamic Adaptive Streaming over HTTP)라는 이름으로 표준화가 진행 중에 있다. 이에 본 논문에서는 DASH를 이용한 효율적 3D Adaptive 스트리밍 서비스 제공 방안을 제안한다. DASH를 이용한 3D 서비스는 사용자들에게 IP 망을 통해 다양한 품질의 3D 콘텐츠를 제공할 수 있으며, 또한 하나의 3D 콘텐츠로 다양한 디바이스에 적용 가능하다는 이점이 있다.

• 대한전기학회논문지:전력기술부문A
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• 제53권6호
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• pp.324-333
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• 2004

This paper discusses the development of an educational web-based power flow program for undergraduate students. The interaction between lectures and users can be much enhanced via the web-based programs which result in the student's learning effectiveness on the power flow problem. However the difficulties for developing web-based application programs are that there can be the numerous unspecified users to access the application programs. To overcome the aforementioned multi-users problem and to develope the educational web-based power flow program, we have revised the system architecture, the modeling of application programs, and database which efficiently and effectively manages the complex data sets related to the power flow analysis program. The developed application program is composed of the physical three tiers where the middle tier is logically divided into two kinds of application programs. The divided application programs are interconnected by using the Web-service based on XML (Extended Markup Technology) and HTTP (Hyper Text Transfer Protocol) which make it possible the distributed computing technology Also, this paper describes the method of database modeling to handle effectively when the numerous users change the parameters of the power system to compare the results of the base case.

• 대한임베디드공학회논문지
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• 제15권2호
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• pp.79-85
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• 2020

IIoT stands for Industrial Internet of Things used in manufacturing, healthcare, and transportation in networked smart factories. Recently, IIoT's environment requires an automated control system through intelligent cognition to improve efficiency. In particular, IIoT can be applied to automatic calibration of production equipment for improved management in industrial environments. Such automation systems require a wireless network for transmitting industrial data. Self-calibration systems in laser transmission paths using wireless networks can save resources and improve production quality by real-time monitoring and remote control of laser transmission path. In this paper, we propose a wireless networked system for self-calibration of laser equipment that requires a laser transmission path, and we show the results of the prototype evaluation. The self-calibration system of laser equipment measures the coordinates of the laser points with sensors and sends them to the host using the proposed application protocol. We propose a wireless network service for the wired motor controller to align the laser coordinates. Using this wireless network, the host controls the motor by sending a control command of the motor controller in an HTTP message based on the received coordinate values. Finally, we build a prototype system of the proposed design to verify the detection performance and analyze the network performance.

• 한국CDE학회논문집
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• 제7권2호
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• pp.110-120
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• 2002

This paper presents the method that allows easy and rapid integration of legacy resources within the company and between departments. The proposed system can easily construct a distributed environment for collaborative design between departments in the companies. It supports knowledge-based integration system, which allows designers to develop product with deep knowledge about product design. For the purpose, DOME (Distributed Object-based Modeling Environment)-which has been developed through various studies-was used in this paper. To overcome its problems and insufficiency, the Web-Integrator is proposed. The Web-Integrator is very suitable for an Internet environment because it uses HTTP (Hyper Text Transfer Protocol) and XML (extensible Markup Language) as its main communication method. By supporting the remote object access via URL (Uniform Resource Locator), the implementation of the integrated system makes the Web-Integrator systematic and intuitive. All the functions and resources provided by DOME could be used with the interface that enables bi-directional communication with the DOME system. Web-Integrator provides full web-based environments for the general designers, who do not have a full design knowledge and experience, and the proposed system allows design operations to happen at any place and anytime. Also it provides XML-RPC(Remote Procedure Call) based web service framework, which allows other systems to use easily the service that the DOME system supplies regardless the location and the platform.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2004년도 추계학술대회 논문집 전력기술부문
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• pp.94-96
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• 2004

This paper discusses the development of the educational simulator for the electricity spot market in korea. The interaction between lectures and users can be much enhanced via the web-based programs which result in the student's teaming effectiveness on an electricity spot market. However the difficulties for developing web-based application programs are that there can be the numerous unspecified users to access the application programs. To overcome the aforementioned multi-users problem and to develope the educational simulator, we have revised the system architecture, the modeling of application programs, and database which efficiently and effectively manages the complex data sets related to an electricity spot market. The developed application program is composed of the physical three tiers where the middle tier is logically divided into two kinds of application programs. The divided application programs are interconnected by using the Web-service based on XML (Extended Markup Technology) and HTTP (Hyper Text Transfer Protocol) which make it possible the distributed computing technology.

• 한국멀티미디어학회논문지
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• 제20권1호
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• pp.1-9
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• 2017

Explosive deployment of smart mobile devices such as smart phones, and tablets along with expansion of wireless internet bandwidth have enabled the deployment of mobile video streaming such that video traffic becomes the most important service in wireless networks. Recently, for more efficient video streaming services, the ISO MPEG group standardized a protocol called DASH (Dynamic Adaptive Streaming over HTTP) and the standard has been quickly adopted by many service providers such as YouTube and Netflix. Despite of the convenience of mobile streaming services, users also suffer from low QoE(Quality of Experience) due to dynamic channel fluctuations and unnecessary downloading due to high churning rates. This paper proposes a noble efficient video rate selection algorithm considering user buffer level, channel condition and churning rate. Computer simulation based performance study showed that the proposed algorithm improved the QoE significantly compared to a method that determines the video rate based on current channel conditions. Especially, the proposed method reduced the rebuffering rate, one of the most important performance factors of the QoE, to a nonnegligible level.

• 융합정보논문지
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• 제9권9호
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• pp.52-57
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• 2019

DNS는 'Domain Name System'의 약자로, 네트워크 상에서 네트워크에 연결된 장지를 구분하기 위해 IP 주소를 사용하는데, IP는 일반 사용자가 쉽게 기억하기가 어려워 IP에 해당하는 별명같은 이름을 등록하여 관리하는 시스템을 말한다. 최근 들어 이러한 DNS를 악용하는 사례가 해외에서 늘고 있으며, 'DNS피오나지' 라고 불리는 배후 세력들이 새로운 룰과 악성코드를 개발하여 진화하고 있으며, 이런 공격은 해킹 성공률을 높이며, 가짜 사이트로 유도를 하는 등 데이터를 변경하거나 위조하고 있어 피해 사례가 증가되고 있는 상황이다. 글로벌 DNS 시스템 등 점점 통제를 할 수 없는 범위로 확대되고 있어, 이를 통제하기 위해 DNS피오나지 공격에 대한 분석과 대응책을 제시하여 안전한 DNS 시스템을 구축을 제안한다.

• 한국멀티미디어학회논문지
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• 제22권2호
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• pp.194-202
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• 2019

In the information society represented by the Fourth Industrial Revolution, various types of data and information that are difficult to see are produced, processed, and processed and circulated to enhance the value of existing goods. The IoT(Internet of Things) paradigm will change the appearance of individual life, industry, disaster, safety and public service fields. In order to implement the IoT paradigm, several elements of technology are required. It is necessary that these various elements are efficiently connected to constitute one system as a whole. It is also necessary to collect, provide, transmit, store and analyze IoT data for implementation of IoT platform. We designed and implemented a big data processing IoT platform for IoT service implementation. Proposed platform system is consist of IoT sensing/control device, IoT message protocol, unstructured data server and big data analysis components. For platform testing, fixed IoT devices were implemented as solar power generation modules and mobile IoT devices as modules for table tennis stroke data measurement. The transmission part uses the HTTP and the CoAP, which are based on the Internet. The data server is composed of Hadoop and the big data is analyzed using R. Through the emprical test using fixed and mobile IoT devices we confirmed that proposed IoT platform system normally process and operate big data.

• 정보보호학회논문지
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• 제12권6호
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• pp.29-46
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• 2002

인증을 지원하고 비밀통신 설정을 위한 안전한 수단을 제공하기 위해 보편적으로 이용하고 있는 것이 X.509 v3 인증서를 이용하는 SSL/TLS 프로토콜이다. X.509 PKI는 아주 복잡하고도 불완전하기 때문에 이를 보완하기 위한 연구의 결과로 SPKI/SDSI가 탄생하였다. 본 논문은 기존의 Geronimo 프로젝트로 구현된 SPKI/SDSI 서버가 지니지 못한 비밀통신과 역할기반 접근제어 기능을 수행하는 보안모듈들을 추가하고, 온라인으로 이름&권한-인증서를 전담해 발행하는 이름&권한 위임 모듈을 탑재한 보안서버를 설계하며 그의 프로토타입을 구현함이 목적이다. 그리고 이 프로토타입의 구현이 웹상에서 어떻게 적용되는지를 실제 예를 통해 보였다.

• International Journal of Computer Science & Network Security
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• 제22권1호
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• pp.269-275
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• 2022

Public healthcare has recently become an issue of great importance due to the exponential growth in the human population, the increase in medical expenses, and the COVID-19 pandemic. Speed is one of the crucial factors in saving life, particularly in case of heart attack. Therefore, a healthcare device is needed to continuously monitor and follow up heart health conditions remotely without the need for the patient to attend a medical center. Therefore, this paper proposes a portable electrocardiogram (ECG) monitoring system to improve healthcare for heart attack patients in both home and ambulance settings. The proposed system receives the ECG signals of the patient and sends the ECG values to a MySQL database on the IoT-cloud via Wi-Fi. The signals are displayed as an ECG data chart on a webpage that can be accessed by the patient's doctor based on the HTTP protocol that is employed in the IoT-cloud. The proposed system detects the ECG data of the patient to calculate the total number of heartbeats, number of normal heartbeats, and the number of abnormal heartbeats, which can help the doctor to evaluate the health status of the patient and decide on a suitable medical intervention. This system therefore has the potential to save time and life, but also cost. This paper highlights the five main advantages of the proposed ECG monitoring system and makes some recommendations to develop the system further.