• Journal of the Korea Institute of Information Security & Cryptology
• /
• v.19 no.6
• /
• pp.49-61
• /
• 2009

Recently, a great attention has been paid to a vehicle black box device in the auto markets since it provides an accident re-construction based on the data which contains audio, video, and some meaningful driving informations. It is expected that the device will get to promote around commercial vehicles and the market will greatly grow within a few years. Drivers who equips the device in their car believes that it can find the origin of an accident and help an objective judge. Unfortunately, the current one does not provide the integrity of the data stored in the device. That is the data can be forged or modified by outsider or insider adversary because it is just designed to keep the latest data produced by itself. This fact cause a great concern in car insurance and law enforcement, since the unprotected data cannot be trusted. To resolve the problem, in this paper, we propose a novel real-time integrity protection scheme for vehicle black box device. We also present the evaluation results by simulation using our software implementation.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.26 no.6
• /
• pp.897-906
• /
• 2022

In this paper, we propose a novel MAC protocol based on the harmonic transmission of ACK, called HAT-LoRa, for improving the reliability and the utilization in multiple gateway LoRa Networks. LoRa is basically vulnerable to collision due to the primitive pure ALOHA-like MAC. Whereas data frame delivery can be guaranteed by the transparent bridge of multiple receiving gateways, ACK is still transmitted by a single gateway in LoRa Network. HAT-LoRa provides the augmented reception opportunity of ACK via the simultaneous transmissions of identical ACK in multiple spreading factors. The proposed method reduces the expected transmission times of ACK double gateway environment as well as single gateway environment, by 55 and 60% in maximum, by 35% and 40% in average, in a single- and double-gateway environment, respectively. Especially, it outperforms under the environment where the distance between end device and gateways are similar to each other.

• Journal of the Korea Society of Computer and Information
• /
• v.27 no.4
• /
• pp.111-118
• /
• 2022

In recent years, the number of single-person elderly households has increased, but when an emergency situation occurs inside the house in the case of single-person households, it is difficult to inform the outside world. Various smart home solutions have been proposed to detect emergency situations in single-person households, but it is difficult to use video media such as home CCTV, which has problems in the privacy area. Furthermore, if only a single sensor is used to analyze the abnormal situation of the elderly in the house, accurate situational analysis is limited due to the constraint of data amount. In this paper, therefore, we propose an algorithm of abnormal situation detection fusion inside the house by fusing 2DLiDAR, dust, and voice sensors, which are closely related to everyday life while protecting privacy, based on their correlations. Moreover, this paper proves the algorithm's reliability through data collected in a real-world environment. Adnormal situations that are detectable and undetectable by the proposed algorithm are presented. This study focuses on the detection of adnormal situations in the house and will be helpful in the lives of single-household users.

• Journal of the Institute of Convergence Signal Processing
• /
• v.23 no.1
• /
• pp.44-49
• /
• 2022

Abstract Recently, with the development of IoT technology and communication media, various video equipment is being used in industrial fields. Image data acquired from cameras and sensors are easily affected by noise during transmission and reception, and noise removal is essential as it greatly affects system reliability. In this paper, we propose a weight filter algorithm based on the pixel value distribution pattern to preserve details in the process of restoring images damaged in AWGN. The proposed algorithm calculates weights according to the pixel value distribution pattern of the image and restores the image by applying a filtering mask. In order to analyze the noise removal performance of the proposed algorithm, it was simulated using enlarged image and PSNR compared to the existing method. The proposed algorithm preserves important characteristics of the image and shows the performance of efficiently removing noise compared to the existing method.

• Journal of Korea Society of Industrial Information Systems
• /
• v.27 no.5
• /
• pp.119-128
• /
• 2022

This study investigated the influence relationship of information service using QR code on customer's service quality perception and loyalty behavior for medical service in the physical environment. As a result of the study, when medical institutions provide location information services about the physical environment by utilizing the usefulness and reliability of QR codes, the perceived quality of customers' QR information will be strengthened, and furthermore, loyalty behavior toward medical services will increase in the future. Considering the spread of smartphones as a popular digital medium today, marketers use QR codes to connect and provide four-dimensional information services without time and place restrictions, thereby strengthening the interactive experience with customers. And these efforts suggest that it can contribute to improving service image and strengthening loyalty beyond simply providing service information to companies.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.26 no.2
• /
• pp.239-250
• /
• 2022

LoRa is a physical layer technology designed to secure highly reliable long-range communication with introducing loco parentis tree network and chirp spreading spectrum. Since since a leaf can send message to more than one parents simultaneously with a single transmission in a region, packet delivery ratio increases logarithmically as the number of gateways increases. The delivery ratio, however, dramatically collapses even under loco parentis tree topology due to the limitations of ALOHA-like primitive MAC, . The proposed method is intended to exploit SDMA approach to reuse frequency in an area. With the view, TxPower of each sender for each message in a concurrent transmission is elaborately controlled to survive the collision at different gateway. Thus, the gain from the capture effect improves the capacity of resource-hungry Low Power and Wide Area Networks.

• Journal of Korean Library and Information Science Society
• /
• v.53 no.4
• /
• pp.25-44
• /
• 2022

The purpose of this study is to examine how the content components of information literacy textbooks develop and is to find implications for improving of textbook publication. Three kinds of information literacy textbooks were published sequentially over time. The content components of 『Information and media』(1996) and 『Library and information skills』(2011) are processed by filament structure and 『Information and library』(2002) has a topic-driven project activity. Generally, a small lesson unit of the textbook consisted of three components (learning goals, learning contents, learning activities) and each component in the unit have to make semantic close relationships. However, in some information literacy textbooks, there are cases that the semantic relationship between goals, contents, and activities are cut off. This disconnection cases can be a fatal drawback for the reliability of textbooks, so sufficient attention is needed to develop information literacy textbooks later.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2021.10a
• /
• pp.194-198
• /
• 2021

LoRa is a physical layer technology that is designed to provide a reliable long-range communication with introducing CSS and with introducing a loco parentis tree network. Since a leaf can utilize multiple parents at the same time with a single transmission, PDR increases logarithmically as the number of gateways increases. Because of the ALOHA-like MAC of LoRa, however, the PDR degrades even under the loco parentis tree topology similarly to the single-gateway environment. Our proposed method is aimed to achieve SDMA approach to reuse the same frequency in different areas. For that purpose, it elaborately controls each TxPower of the senders for each message in concurrent transmission to survive the collision at each different gateway. The gain from this so-called capture effect increases the capacity of resource-hungry LPWAN. Compared to a typical collision-free controlled-access scheme, our method outperforms by 10-35% from the perspective of the total count of the consumed time slots. Also, due to the power control mechanism in our method, the energy consumption reduced by 20-40%.

• Proceedings of the Korean Society of Computer Information Conference
• /
• 2022.01a
• /
• pp.49-51
• /
• 2022

본 논문에서는 신생아집중치료실에 입원한 미숙아와 가족 대상의 증강현실(Augmented Reality [AR])기반 맞춤형지지 케어 프로그램 개발에 필요한 관련 전문가 합의를 도출한 델파이 조사 연구이다. 3D 콘텐츠를 적용한 프로그램 개발에 필요한 핵심 구성요소 혹은 교육 콘텐츠를 발굴하여 개발의 방향성을 제안하기 위한 델파이 분석에, 미숙아 및 전문가 집단 14명(1차)과 113명(2차)이 본 연구에 참여하였다. 각 델파이 집단에서 수집된 반응들의 분석 결과, 4개의 하위영역(AR 프로그램의 필요성 및 가치(장점), AR 기반 프로그램 도입과 적용 시 고려할 점, AR 기반 전인적 e케어 프로그램 도입 시 요구와 전략적 방안, 입원 초기부터 퇴원 전 단계별 지지케어 위한 3D 콘텐츠 개발 우선순위)이 분류되었으며, 총 57문항이 도출되었다. 입원 초기부터 퇴원 전 단계별 지지케어 위한 3D 콘텐츠 개발 요구도와 우선순위에 있어서는, 부모 경우 신생아 케어의 반복적 체험 훈련 통한 부모 교육, 아기 본연의 독특하고 고유한 캐릭터나 습관 및 특성 관련 정보 공유, 발달을 돕는 양육 또는 놀이 교육, 가족 요구 기반 특수 간호 기술 훈련 등의 항목의 우선순위가 높았다. 한편, 전문가의 경우 건강한 부모역할로의 이행을 돕기 위한 심리사회적지지, 부모-아기 간 단절 최소화, 미숙아 발달 관련 정보 및 양육 또는 놀이 정보 공유, 부모-아기 상호작용 기회 제공 등으로 요구도의 우선순위가 높았다. 본 연구에서 개발된 델파이 평가문항의 내적일관성 신뢰도를 분석한 결과, Cronbach's α .89~.94로 높았고, 타당도와 문항 구성이 적절한 것으로 나타났다. 본 연구의 결과들을 바탕으로, 미숙아와 가족을 위한 AR 기반 맞춤형지지 케어 프로그램 개발의 적합성이 검증되었고, 프로그램의 임상적, 기술적, 사용적 가치에 있어서 고려할 사항과 교수매체로서 부모와 전문가 집단이 요구하는 3D 콘텐츠 우선순위를 바탕으로 효과적인 기획 및 설계의 근거를 확보했다는 점에서 의의가 있다.

• Journal of Advanced Navigation Technology
• /
• v.26 no.6
• /
• pp.481-486
• /
• 2022

The recent rapid growth of the IoT(Internet of Things) is leading to the spread of low-power wireless technology. A major challenge in designing IoT wireless networks is to achieve coexistence between different wireless technologies that share the 2.4 [GHz] ISM (Industrial Scientific Medical) frequency band. Therefore, there is a need for research on improving the reliability of wireless networks and coexisting operation between wireless networks. In particular, it is necessary to study an interference model and performance for mutual service coexistence in a BLE (Bluetooth Low Energy) wireless network environment, which is expected to be widely used as a connection medium between devices in various industrial fields. In this paper, the co-channel interference model with the IEEE 802.15.4 system is established focusing on the physical layer of the BLE system widely used in residential and industrial wireless applications, and the performance of the BLE wireless communication system is analyzed in the co-channel interference environment. As a result of the analysis, as the distance between the interference source and the BLE system increases in an environment where noise and co-channel interference exist, the amount of co-channel interference decreases and the error rate performance of the BLE system improves.