• Journal of Korea Society of Industrial Information Systems
• /
• v.16 no.4
• /
• pp.53-65
• /
• 2011

As the Information and Communication Technologies continue to advance, some sensitive services (e.g. e-commerce, on-line financial service, and etc.) have spread rapidly. Accordingly, ensuring the safety of the sensitive service itself using personal Information as well as the protection of personal Information Is becoming very important. In addition, with the popularization of smart phone and the universalized use of wireless Internet, many services that have been provided on the basis of the conventional wired network are increasingly propagating to wired and wireless converged network environment. These changes in the network environment requires new paradigm for the pursuit of safe and stable communication. In this paper, we propose seamless and secure service framework that can facilitate a sustainable secure connection between the user terminal and the sensitive service system by using both the personal and network Information. The proposed service framework is capable of isolating the source of authorized use by a third party of the personal Information as far as the user terminal is not lost, although some personal Information is disclosed. Besides, it can provide a seamless and safe service environment even if the access network is changed by relocation of terminals in the heterogeneous mobile network environment.

• Journal of Practical Engineering Education
• /
• v.8 no.2
• /
• pp.111-120
• /
• 2016

Education equipment for field programmable gate array (FPGA) design of sensor-based IOT (Internet Of Thing) system is introduced. Because sensors have different interfaces, several types of interface controller on FPGA need. Using this equipment, several types of interface controller, which can control ADC (analog-to-digital converter) for analog sensor outputs and $I^2C$ (Inter-Integrated Circuit), SPI (Serial Peripheral Interface Bus), and GPIO (General-Purpose Input/Output) for digital sensor outputs, can be designed on FPGA. Image processing hardware using image sensors and display controller for real and image-processed images or videos can be design on FPGA chip. This equipment can design a SOC (System On Chip) consisting of a hard process core on Linux OS and a FPGA block for IOT system which can communicate with wire and wireless networks. Using the education equipment, an example of hardware design using image sensor and accelerometer is described, and an example of syllabus for "Digital system design using FPGA" course is introduced. Using the education equipment, students can develop the ability to design some hardware, and to train the ability for the creative capstone design through conceptual, partial-level, and detail designs.

• Journal of KIISE:Computing Practices and Letters
• /
• v.13 no.7
• /
• pp.433-441
• /
• 2007

The bio-Sensors, which are sensing the vital signs of human bodies, are largely used by the medical equipment. Recently, the sensor network technology, which composes of the sensor interface for small-seize hardware, processor, the wireless communication module and battery in small sized hardware, has been extended to the area of bio-senor network systems due to the advances of the MEMS technology. In this paper we have suggested a design and implementation of a health care information system(called u-EMS) using a bio-sensor network technology that is a combination of the bio-sensor and the sensor network technology. In proposed system, we have used the following vital body sensors such as EKG sensor, the blood pressure sensor, the heart rate sensor, the pulse oximeter sensor and the glucose sensor. We have collected various vital sign data through the sensor network module and processed the data to implement a health care measurement system. Such measured data can be displayed by the wireless terminal(PDA, Cell phone) and the digital-frame display device. Finally, we have conducted a series of tests which considered both patient's vital sign and context-awared information in order to improve the effectiveness of the u-EMS.

• 한국HCI학회:학술대회논문집
• /
• 2007.02b
• /
• pp.70-77
• /
• 2007

모바일 IT와 무선인터넷의 발달에 따라 디지털 컨텐츠를 담는 뉴미디어로서의 휴대폰의 가능성은 점차 확대되고 있으며, 모바일 컨텐츠 시장도 급속도로 성장하고 있다. 무선인터넷의 발달은 유선 인터넷 컨텐츠를 무선으로 확장하게 하였으며, 장소기반 관광 정보 (Location Based Information) 서비스가 우선적으로 구축되고 있다. 그러나, 현재 모바일 기기로 서비스되고 있는 대부분의 관광정보는 관광지에 대한 간단한 설명, 교통편, 숙박, 음식점 등 매우 실용적이고 일반적이어서 편리하긴 하지만, 그다지 사용하고 싶은 매력은 없는 정보에 그치고 있다. 본 연구는 기술적으로 진화하고 있는 유비쿼터스 도시 환경에서 모바일을 활용하여 어떠한 새로운 형태의 관광 컨텐츠가 가능해질 수 있을까 하는 질문에서 출발하였다. 본 논문은 정보통신연구 진흥원의 지원을 받아 진행했던 지역의 역사, 문화 정보 전달을 위한 모바일 투어 게임 "타임트렉" 프로토타입 개발에 관한 리서치, 컨셉, 프로세스를 정리한 것이다. "타임트렉" 프로젝트에서 추구했던 방향은 문화적, 역사적으로 중요한 장소를 투어하면서 모바일 미디어를 활용하여 보다 깊은 역사, 문화 정보를 새롭고 재미있는 방법으로 전달하고자 하는 것이었다. 특히, 사용자의 보다 적극적인 참여와 흥미유발을 위해 시간여행 능력을 가진 탐정이 과거로 시간여행을 통해 사건을 해결하는 롤플레잉 스토리 기반 게임과 물리적 장소에서 답을 찾아야 하는 오프라인 퀘스트 게임의 형식을 포함하는 모바일 투어 게임형태로 구축하였다. 이렇게 함으로써 관광객들에게 보다 그 장소에 대해 알고 싶어 하는 흥미를 유도하고 투어를 완료하게 유도함으로써 만족스럽고 새로운 관광 경험을 제공하는 것을 목적으로 하였다. 새로운 타입의 모바일 관광서비스의 프로토타입 개발에 있어 중점을 두었던 부분은 역사적으로 중요한 장소를 워킹 트레일로 구성하고 그 장소가 가지는 기본적인 문화, 역사적 정보에 오락적 요소(스토리와 게임 요소)를 자연스럽게 혼합하여 흥미로운 컨텐츠를 만들는 것이었으며, 또한 모바일이 가진 위치기반 서비스 기능을 활용하여 효과적으로 컨텐츠를 적재적소에 제시하는 인터페이스 구현에 중점을 두었다. 논문에서는 먼저, 기존의 국내외 모바일 관광정보서비스의 사례 및 연구 동향을 분석하고, 이에 따라 설정한 "타임트렉" 프로젝트의 방향성과, "타임트렉" 프로젝트에서 개발했던 프로토타입에 대하여 요약, 설명하였으며, 사용자 테스트 과정을 기술하였다. 그리고 마지막으로, 시장 세분화에 따른 관광 정보 서비스의 엔터테인먼트화 전략에 대해 논의하였다. 본 연구에서 시도했던 지역의 역사, 문화 관광을 위한 LBS 모바일 기술과 스토리, 게임 등 엔터테인먼트 요소의 결합은 관광객들에게 새로운 형태의 즐거운 관광 경험을 창출할 수 있으며, 관광 산업과 모바일 컨텐츠 산업의 결합이라는 새로운 접근의 장을 개척할 수 있을 것이다.

• Journal of KIISE:Information Networking
• /
• v.30 no.3
• /
• pp.377-386
• /
• 2003

In this paper, we present an application layer protocol to support secure wireless Internet services, called Application Layer Security(ALS). The drawbacks of the two traditional approaches to secure wireless applications motivated the development of ALS. One is that in the conventional application-specific security protocol such as Secure HyperText Transfer Protocol(S-HTTP), security mechanism is included in the application itself. This gives a disadvantage that the security services are available only to that particular application. The other is that a separate protocol layer is inserted between the application and transport layers, as in the Secure Sockets Layer(SSL)/Transport Layer Security(TLS). In this case, all channel data are encrypted regardless of the specific application's requirements, resulting in much waste of network resources. To overcome these problems, ALS is proposed to be implemented on top of HTTP so that it is independent of the various transport layer protocols, and provides a common security interface with security applications so that it greatly improves the portability of security applications. In addition, since ALS takes advantages of well-known TLS mechanism, it eliminates the danger of malicious attack and provides applications with various security services such as authentication, confidentiality integrity and digital signature, and partial encryption. We conclude this paper with an example of applying ALS to the solution of end-to-end security in a present commercial wireless protocol stack, Wireless Application Protocol.

• Journal of IKEEE
• /
• v.25 no.1
• /
• pp.156-167
• /
• 2021

In this paper, we propose a digital transceiver unit design for in-building of 5G optical repeaters that extends the coverage of 5G mobile communication network services and connects to a stable wireless network in a building. The digital transceiver unit for driving the proposed 5G optical repeater is composed of 4 blocks: a signal processing unit, an RF transceiver unit, an optical input/output unit, and a clock generation unit. The signal processing unit plays an important role, such as a combination of a basic operation of the CPRI interface, a 4-channel antenna signal, and response to external control commands. It also transmits and receives high-quality IQ data through the JESD204B interface. CFR and DPD blocks operate to protect the power amplifier. The RF transmitter/receiver converts the RF signal received from the antenna to AD, is transmitted to the signal processing unit through the JESD204B interface, and DA converts the digital signal transmitted from the signal processing unit to the JESD204B interface and transmits the RF signal to the antenna. The optical input/output unit converts an electric signal into an optical signal and transmits it, and converts the optical signal into an electric signal and receives it. The clock generator suppresses jitter of the synchronous clock supplied from the CPRI interface of the optical input/output unit, and supplies a stable synchronous clock to the signal processing unit and the RF transceiver. Before CPRI connection, a local clock is supplied to operate in a CPRI connection ready state. XCZU9CG-2FFVC900I of Xilinx's MPSoC series was used to evaluate the accuracy of the digital transceiver unit for driving the 5G optical repeater proposed in this paper, and Vivado 2018.3 was used as the design tool. The 5G optical repeater digital transceiver unit proposed in this paper converts the 5G RF signal input to the ADC into digital and transmits it to the JIG through CPRI and outputs the downlink data signal received from the JIG through the CPRI to the DAC. And evaluated the performance. The experimental results showed that flatness, Return Loss, Channel Power, ACLR, EVM, Frequency Error, etc. exceeded the target set value.

• KIPS Transactions on Computer and Communication Systems
• /
• v.9 no.11
• /
• pp.247-249
• /
• 2020

In the era of the 4th industrial revolution, the demand for convergence between ICT technologies is increasing in various fields. Accordingly, a new term that combines data, network, and artificial intelligence technology, DNA (Data, Network, AI) is in use. and has recently become a hot topic. DNA has various potential technology to be able to develop intelligent application in the real world. Therefore, this paper introduces the reviewed papers on the service image placement mechanism based on the logical fog network, the mobility support scheme based on machine learning for Industrial wireless sensor network, the prediction of the following BCI performance by means of spectral EEG characteristics, the warning classification method based on artificial neural network using topics of source code and natural language processing model for data visualization interaction with chatbot, related on DNA technology.

• Proceedings of the Korea Contents Association Conference
• /
• 2009.05a
• /
• pp.526-531
• /
• 2009

Recently, many interests on the ubiquitous environment and the practical technologies associated with it have been significantly increasing along with the rapid development of wireless technologies. The development of the automated systems based on the ubiquitous environment is required as the concept of the term "ubiquitous" is integrated into the fields of existing IT. In this paper, we design and implement a power-saving management system using RFID/USN technologies. It efficiently manages the power consumption of the electronic machine such as electric lights, electric heaters, and air conditioners in a building. The proposed system controls the electronic machines and monitors their status by RFID and collects the real time information about the surroundings and power consumption of the electronic machines by USN. Especially, it analyzes the real time information and supports the intelligent scheduler with the best power-saving. Finally, this paper shows the difference between the proposed system and the existing systems and the reality of our system through the real time user interface about the power-saving management.

• Journal of the Institute of Electronics Engineers of Korea TC
• /
• v.43 no.8 s.350
• /
• pp.25-34
• /
• 2006

In this paper DynaMoNET is suggested as a novel IPv6-based multi-homed mobile network architecture which is composed of nested mobile ad hoc networks dynamically coming together through wireless personal area networks. Each ad hoc network has a mobile router which may work as a root mobile router instead of fixed mobile routers in a DynaMoNET. A root mobile router provides the reliable Internet connectivity for the entire mobile network. This paper includes a innovative handover protocol for multi-homed mobile networks, network switchover algorithm considering multiple decision factors, root mobile router election process based on token-based algorithm fast root mobile router discovery algorithm and fault avoidance mechanism to support reliable Internet connectivity. Finally the system architecture of a mobile router is given in detail.

• Journal of KIISE:Information Networking
• /
• v.32 no.1
• /
• pp.110-122
• /
• 2005

Bluetooth has been reputed as a wireless networking technology supplying ad-hoc networks between digital devices. In particular, bluetooth scatternet is a most essential part for dynamic ad-hoc networks. But past researches on bluetooth scatternet has hardly treated dynamic scatternet environment. In this paper, we proposed a scatternet reformation algorithm for the case that some nodes escape from the scatternet. The proposed algorithm is a general algorithm which can be applied to many types of bluetooth scatternet regardless of the topology. The proposed algorithm has short reformation time delay because the process has only page process (not including inquiry process ). The algorithm is operated based on Recovery Node Vector which is composed of Recovery Master and Recovery Slave. In this paper, we performed the real hardware experiments for evaluating the performance of the proposed algorithm. In that experiments, we measured the reformation time and reformation probability. In comparison with the case including inquiry process, the proposed algorithm had the improvement in reformation time delay and we obtained high success rate over 97%.