• Journal of the Korea Institute of Information Security & Cryptology
• /
• v.7 no.3
• /
• pp.53-64
• /
• 1997

When we apply a synchronous stream cipher to the T1 carrier system, it can occur long consecutive 0's(or 1's) sequences in the received data. In this case, it is difficult to recover receiver clock and violates a communication protocol. This paper proposes block detection and serial detection method which suppress 0's sequences of more than k( $\geq$ 2) of the stream ciphertext in the T1 carrier system. These ZS methods keep security level and solve problems of stream synchronization.

• Proceedings of the Korean Society of Broadcast Engineers Conference
• /
• 2022.11a
• /
• pp.236-239
• /
• 2022

증강현실로 날씨, 뉴스 요약 등이 제공되거나 AI 비서 기능을 제공하는 스마트 미러(smart mirror)가 개발되고 있다. 본 작품에서는 IoT 통합제어, 뉴스 요약 및 날씨 정보 제공 등의 서비스를 하나의 웹 플랫폼으로 구축하고 이를 손가락 제스쳐 및 음성 명령으로 제어하는 것을 제안하고 구현하였다. 본 작품에서는 음성 인식을 통해 IoT 서비스를 직관적으로 이용할 수 있게끔 설계하여 사용자의 편의성을 높였으며, 디바이스를 직접 터치하는 방식이 아닌 finger gesture로 제어하는 방식을 채택해, 디바이스 유지 보수 및 위생 문제를 해결하였다. 단순 IoT 통합 제어 기능뿐만 아니라 다양한 컨텐츠 및 기능을 제공함으로써 통합 플랫폼의 기능을 수행할 수 있도록 하였다. 뉴스 홈페이지에서 Crawling한 뉴스를 text rank 알고리즘을 이용. 자동으로 요약하는 기능과, 사용자의 IP를 기반으로 위도와 경도를 추론, 해당 지역의 일기 예보 정보를 표현해 주는 등 단순 IoT 제어 플랫폼이 아닌, 통합 플랫폼의 기능을 다하도록 설계하였다. 이처럼 다양한 정보를 압축해서 사용자가 편하게 볼 수 있도록 제공하며, 직관적인 two track 제어 방식을 채택. 사용 대상의 편의성을 증대시켜 본 프로젝트는 기존 프로젝트보다 사용자에게 더 나은 사용 경험을 제공할 것이다.

• The Journal of the Institute of Internet, Broadcasting and Communication
• /
• v.10 no.5
• /
• pp.69-75
• /
• 2010

Advanced T-DMB(Terrestial DMB )system which is a new portable mobile broadcasting system has been developed to increase data rate up to double of conventional T-DMB in same bandwidth while maintaining backward compatibility, using hierarchical modulation method. The Advanced T-DMB system realize high qualification of conventional T-DMB system by adding BPSK signal or QPSK signal as enhanced layer to existing DQPSK signal. The enhanced layer signal should be small enough to maintain backward compatibility and to minimize the coverage loss of existing T-DMB service area. But this causes the enhanced layer signal of Advanced T-DMB susceptible to fading effect in transmission channel. In this paper we applied the duo-binary turbo code which has powerful error correction capability to the enhanced layer signal for compensating channel distortion. And the computer simulation results about the performance of the duo-binary turbo code in Advanced T-DMB system are presented along with analysis comments.

• Journal of IKEEE
• /
• v.22 no.2
• /
• pp.289-301
• /
• 2018

IIoT, the IoT technology applied to the industrial field, is being used as a monitoring technology for increasing in production rate and safety of workers. However, monitoring through the construction of IIoT network using Ethernet and RS485 in production lines where dozens to hundreds of machine tools are manufacturing components, have difficulties of infrastructure cost and network flexibility and fluidity. Therefore, in this paper, using IEEE 802.15.4 standard WSN device to construct a Ad-Hoc WSN in the production line. In addition, the transmission period and order of the sensor nodes are set by applying the EtherCAT communication method in which the payload frames are shared by all the sensor nodes. From this, we have overcome the problem of reliability decline and real-time issue due to the packet collision of wireless network and confirmed that it is a wireless network routing method that can be used in the actual industrial field.

• The Journal of the Institute of Internet, Broadcasting and Communication
• /
• v.15 no.3
• /
• pp.1-6
• /
• 2015

The IoT(Internet of things) technology enable objects around user to be connected with each other for sharing information. To support security is the mandatory requirement in IoT because it is related to the disclosure of private information but also directly related to the human safety. However, it is difficult to apply traditional security mechanism into lightweight devices. This is owing to the fact that many IoT devices are generally resource constrained and powered by battery. PSK(Pre-Shared Key) based approach, which share secret key in advance between communication entities thereafter operate security functions, is suitable for light-weight device. That is because PSK is costly efficient than a session key establishment approach based on public key algorithm. However, how to safely set a PSK of the lightweight device in advance is a difficult issue because input/output interfaces such as keyboard or display are constrained in general lightweight devices. To solve the problem, we propose and develop a secure PSK configuration scheme for resource constrained devices in IoT.

• Proceedings of the KIPE Conference
• /
• 2000.07a
• /
• pp.413-416
• /
• 2000

본논문에서는 유도전동기 속도 및 토크 제어시 고조파의 왜형률을 감소시키고 디지털 구현이 용이하며 선형제어 영역을 증가시킬 수 있는 스위칭 방식으로 Space voltage Vector PWM(Pulse Width Modulation) 설명하였으며 시뮬레이션하기 위한 user_tool로써 Matlab/Simulink를 이용하여 SVPWM을 구현하는 방법을 설명하였다 결과적으로 개루프 운전 시 유도기에 인가되는 기준전압을 각각 비과변조와 과변조 시 전압비율 변경방식을 사용하여 나타나는 응답으로 가상스위칭 시간 T1, T2, T0 와 속도, 상전류, 토크응답을 알아보았다.

• Proceedings of the Korea Information Processing Society Conference
• /
• 2023.11a
• /
• pp.130-131
• /
• 2023

비닐하우스는 농업 분야에서 매우 일반적으로 사용되는 구조물로, 식물을 보호하고 작물 수확량을 늘리는 데 사용된다. 그러나 비닐하우스는 보안, 위협에 취약하다. 본 논문은 비닐하우스의 보안에 대한 연구를 다룬다. 본 연구로 비닐하우스의 기존 보안 방식에서 IoT를 활용한 보안 방식으로 바꾸어 침입자의 피해에 더욱 발 빠르게 대처가 가능하게 하였다.

• The Journal of the Institute of Internet, Broadcasting and Communication
• /
• v.11 no.6
• /
• pp.135-141
• /
• 2011

Analog medias are converting to digital with the development of the digital communications. The Korean radio broadcasting services yet on analog and the research for the digital radio is progressing. The digital conversion of radio broadcasting has already progressed in foreign countries because of the technical limitation of analog broadcasting(The radio-frequency efficiency is poor). DAB is one of the digital radio mode, it doesn't use on AM/FM band and uses on T-DMB frequency band. So, it has an advantage of being able to broadcast with the existing radio without interference at once. On the other hand, it has the potential to cause interference to existing T-DMB broadcasting. In this paper, we propose an efficient DAB channel allocation method for digital radio on T-DMB frequency band. This paper allocates the DAB channel without interference to existing T-DMB broadcasting and proves the proposed method through simulations for the interference analysis.

• KIPS Transactions on Software and Data Engineering
• /
• v.5 no.8
• /
• pp.351-360
• /
• 2016

Sensors equipped in Internet-of-Thing (IoT) devices are used to measure the surrounding contexts, and IoT applications analyze the contexts to infer situations and provide situation-specific smart services. There are different context acquisition schemes including pulling, pushing, and broadcasting. Most IoT devices support only one of the schemes. Hence, there can be an incompatible issue on data acquisition schemes between applications and devices, and consequently it could result in an increased development cost and inefficiency on application maintenance. This paper presents design patterns which can effectively remedy the incompatibility problem. By applying the patterns, IoT applications with incompatibility can be systematically and effectively developed. And, also its maintainability is expected to increase.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.8 no.6
• /
• pp.1188-1193
• /
• 2004

So far, there have been grossly 3 types of studies on GF(2m) multiplier architecture, such as serial multiplication, array multiplication, and hybrid multiplication. Serial multiplication method was first suggested by Mastrovito (1), to be known as the basic CF(2m) multiplication architecture, and this method was adopted in the array multiplier (2), consuming m times as much resource in parallel to extract m times of speed. In 1999, Paar studied further to get the benefit of both architecture, presenting the hybrid multiplication architecture (3). However, the hybrid architecture has defect that only complex ordo. of finite field should be used. In this paper, we propose a novel approach on developing serial multiplier architecture based on Mastrovito's, by modifying the numerical formula of the polynomial-basis serial multiplication. The proposed multiplier architecture was described and implemented in HDL so that the novel architecture was simulated and verified in the level of hardware as well as software. The implemented GF(2m) multiplier shows t times as fast as the traditional one, if we modularized the numerical expression by t number of parts.