• The Journal of the Korea institute of electronic communication sciences
• /
• v.8 no.7
• /
• pp.1017-1023
• /
• 2013

Datacommunications transmit the source codes that are coded in information devices, such as computer to the transmission line by means of the line coded signal. AMI method is applied to the line coding method to transmit the signal for long distance. The disadvantage of the AMI method is to loss the bit synchronization when consecutive binary bit '0' over 4ea is coming into line coder. The scrambling technique is used to overcome the problem. The HDB-3 scrambling method is used in Korea standard which standard in ITU-T. When the HDB-3 technology is used. the method should convert the consecutive bit '0' over 4ea to certain bits format. As a result, when there are many such kind of '0' bit stream in source codes, data transmission efficiency will be decreased to treat in line coder, etc. This paper is directed to study the Roman character code system in $KS{\times}1001$, Korea standard for information exchange code in datacommunication systems. Based on the study result, this paper proposed the maximum optimized Roman character code system. In the study, Character coding rule for $4{\times}4$bits and the statistical data for roman character using frequency were considered to simulate. The paper shows the result that when the proposed new roman character coding system is applied to use, the data transmission efficiency could be increased to about 134% compared to existing code system.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
• /
• v.11 no.5
• /
• pp.514-520
• /
• 2018

Presence service provides various information about users such as locations, status of on/offline and network access methods, and number of presence resources required by each users increases largely in mobile environment. Therefore an effective method which can reduce load of presence servers is needed. In this paper, a large scale distributed presence service system which can distribute effectively total presence system load of presence servers using message control session has been presented. This large scale distributed presence service system provides various presence information for massive volumes of users. In this study, a new message control session architecture which can dynamically distribute loads of the presence servers to multiple servers has been presented, and a new presence information data architecture for controlling load of the presence servers has been designed. In this architecture, each presence server can exchange current load level in real time to get variance of the total system load change according to user numbers, and can distribute system load to maintain load level of each server evenly. The performance of the proposed large scale distributed presence service system has been analysed by experiments. The results has been showed that average presence resource subscription processing time reduced from 42.6% to 73.6%, and average presence notification processing time reduced from 37.6% to 64.8%.

• Journal of Internet Computing and Services
• /
• v.17 no.6
• /
• pp.33-39
• /
• 2016

With recent advances in sensor technology, CMOS-based semiconductor devices and networking protocol, the areas for application of wireless sensor networks greatly expanded and diversified. Such diversification of uses for wireless sensor networks creates a multitude of beneficial possibilities for several industries. In the application of wireless sensor networks for monitoring systems' data transmission process from the sensor node to the sink node, transmission through multi-hop paths have been used. Also mobile sink techniques have been applied. However, high energy costs, unbalanced energy consumption of nodes and time gaps between the measured data values and the actual value have created a need for advancement. Therefore, this thesis proposes a new model which alleviates these problems. To reduce the communication costs due to frequent data exchange, a State Prediction Model has been developed to predict the situation of the peripheral node using a geographic autocorrelation of sensor nodes constituting the wireless sensor networks. Also, a Risk Analysis Model has developed to quickly alert the monitoring system of any fatal abnormalities when they occur. Simulation results have shown, in the case of applying the State Prediction Model, errors were smaller than otherwise. When the Risk Analysis Model is applied, the data transfer latency was reduced. The results of this study are expected to be utilized in any efficient communication method for wireless sensor network monitoring systems where all nodes are able to identify their geographic location.

• The Journal of the Convergence on Culture Technology
• /
• v.7 no.1
• /
• pp.654-661
• /
• 2021

Air pollution caused by industrial development has become a level that can seriously threaten human health. In general, indoor air pollution is considered to be lower than outdoors, but modern people live indoors most of the time, thus it is essential to keep the indoor air quality comfortable in order to take care of one's own health and improve the quality of life. Therefore, the development of an indoor environment management platform using Internet of Things and data processing technology, which is currently drawing attention, is considered a very meaningful study. In this paper, we designed an IoT-based management platform that can remotely monitor and control indoor environments. In addition, the functions of the IoT terminal, gateway, and data server constituting the platform were implemented using open source and open libraries, and all functional operations were also verified. In particular, the IoT terminal and the gateway in this paper exchange data using BLE communication, so they can operate with relatively low power and since the gateway uses the BLE Advertising mode, it has the advantage of automatically recognizing IoT terminals that have not been previously configured.

• Journal of the Korea Institute of Information Security & Cryptology
• /
• v.20 no.4
• /
• pp.41-52
• /
• 2010

Message authentication is an essential security element in vehicular ad-hoc network(VANET). For a secure message authentication, integrity, availability, privacy preserving skill, and also efficiency in various environment should be provided. RAISE scheme has been proposed to provide efficient message authentication in the environment crowded with lots of vehicles and generally considered to be hard to provide efficiency. However, as the number of vehicles communicating in the area increases, the overhead is also incurred in proportion to the number of vehicles so that it still needs to be reduced, and the scheme is vulnerable to some attacks. In this paper, to make up for the vulnerabilities in dense vehicular communication network, we propose a more secure and efficient scheme using a process that RSU(Road Side Unit) transmits the messages of neighbor vehicles at once with Bloom Filter, and timestamp to protect against replay attack. Moreover, by adding a handover function to the scheme, we simplify the authentication process as omitting the unnecessary key-exchange process when a vehicle moves to other area. And we confirm the safety and efficiency of the scheme by simulating the false positive probability and calculating the traffic.

• The Journal of Korean Academy of Prosthodontics
• /
• v.60 no.3
• /
• pp.276-282
• /
• 2022

Close communication between clinicians and dental technicians is an important factor in providing successful prostheses. The exchange of opinions with laboratories has mainly been in the form of written prescriptions and a photos, but it has been reported that information transmission may be limited. Currently, as digital technology-based prosthesis fabrication is common, 3D image objects can be stored on the web and can be easily viewed through a mobile web browser. In this article, we introduce cases where the design of the prosthesis was improved by designing the prosthesis using CAD software and reviewing the prosthesis designed with the clinical side through a web viewer. Through this protocol, it was possible to improve the occlusal surface and crown contour, the opposing teeth condition, the size of the gingival embrasure, and the shape of pontic. The process of sharing, discussing, and modifying the prosthesis design with the clinician and technician through a web viewer contributes to reflecting the diversity of oral conditions and individualized needs, thereby helping to make functional and esthetic prostheses.

• Journal of Korea Entertainment Industry Association
• /
• v.15 no.2
• /
• pp.123-135
• /
• 2021

The data processing of this study is focused on keywords related to 'Corona 19 and professional baseball' and 'Corona 19 and professional baseball no spectators', using text mining and social network analysis of textom program to identify problems and view quality. It was used to set the variable of For quantitative analysis, a questionnaire on viewing quality was constructed, and out of 270 survey respondents, 250 questionnaires were used for the final study. As a tool for securing the validity and reliability of the questionnaire, exploratory factor analysis and reliability analysis were conducted, and IPA analysis (importance-satisfaction) was conducted based on the questionnaire that secured validity and reliability, and the results and strategies were presented. As a result of IPA analysis, factors related to the image (image composition, image coloration, image clarity, image enlargement and composition, high-quality image) were found in the first quadrant, and the second quadrant was the game situation (support team game level, support player game level, star). Player discovery, competition with rival teams), game information (match schedule information, player information check, team performance and player performance, game information), interaction (consensus with the supporting team), and some factors appeared. The factors of commentator (baseball-related knowledge, communication ability, pronunciation and voice, use of standard language, introduction of game-related information) and interaction (real-time communication with the front desk, sympathy with viewers, information exchange such as chatting) appeared.

• Journal of Korea Entertainment Industry Association
• /
• v.13 no.3
• /
• pp.91-100
• /
• 2019

It is an undeniable that cultural landscape of Korea is centered in Seoul, where all the cultural powers are oriented. From this aspect, a municipal theatre of Daegu (Daegu Municipal Theatre), where is considered an area somewhat isolated from the perspective of culture, has managed to develop theoretical programs serving public purposes through efforts on the diversification of performance programs, development of creative plays, acceptance of open direction, classic, modern and experimental plays, foreign exchange, musicals and non-verbal, development of modern and post-modern history of the region, aggressive exploration of subjects, and characterization of the theater through citizen-participated programs and communication with citizens. With such efforts on diversification of public benefits and communality conforming to its purpose, it has been recognized for its contribution to the recovery of popularity of performance art and plays in Daegu. The Daegu Municipal Theatre, celebrating the 20th anniversary of establishment this year and having Choi Ju-Hwan as its fifth art director, has managed to conduct various experimental attempts to gain popularity and these include the exploration of the region and its historical figures, development and promotion of creative musicals, and promotion of communication between citizens and performance culture and of participation of audiences, in turn having a stabilized operation system. Such changes are seemed to be attributable to the maturity of performance production and roles of senior members. From this aspect, this study aims at investigating the changes in the Daegu Municipal Theatre and 'roles and popularity of national/public theatre companies.

• Journal of International Area Studies (JIAS)
• /
• v.13 no.4
• /
• pp.251-284
• /
• 2010

Through specific cases, this article examines the causes and measures to overcome cultural divergences most frequently encountered by Koreans living in Vietnam and Korean-contacting Vietnamese in terms of mode of communication, mode of living and mode of doing business. Historical reality proves that Vietnam and Korea have a lot in common in history, culture and society, due to the influence from the Chinese culture on both countries. However, each country has its own acculturation, hence, there exist, apart from the normal dissimilarities, differences between the two countries especially in natural environment andpolitical systems. As a result, in Vietnam, Koreans and Vietnamese have met with quite a lot of divergences in communication, business and living activities. In order to overcome these cultural divergences, in addition to the ceaseless efforts made by Koreans in Vietnam and Korean-contacting Vietnamese, there should be concern, assistance as well as cooperation between the people and the authorities of the two countries. We should draw lessons from the groundless or trivial affairs which, springing from the Chinese people's dislike for Koreans, have been blown up and disseminated on the internet; where by we are to reconsider the relationship between Koreans and Vietnamese. What is more, Korea still feels historically ashamed to have sent nearly 350,000 soldiers to the wa rin Vietnam for economic purposes in the past. As our predecessors brought about that historic shame to get bread for our fatherland in exchange, our generation today should approach Vietnam out of a sense of responsibility towards history. Having experienced a period of economic difficulties, Vietnam innovated and started its open-door policy in 1987. However, this event should not be regarded as the reason for us to approach Vietnam with only one rigid economic principle.

• Journal of Advanced Navigation Technology
• /
• v.26 no.6
• /
• pp.496-503
• /
• 2022

In the reality that the fishing population is decreasing and the single-man fishing vessels is increasing, mandatory equipment for navigation and radio equipments for the safety of fishing boats has continued to be added. Therefore, many equipment such as navigation, communication and fishing are installed in the narrow steering room, so it is very confusing and a number of monitors are placed in the front, which is a factor that degrades the function of maritime observation. To solve this problem, we studied an interface that integrates and operates to major radio facilities such as very high frequency-digital selective calling equipment (VHF-DSC), automatic identification system (AIS) and fishing boat location transmission device (V-pass) into one multi function display (MFD) based on LAN. In addition, IEC61162-450 UDP packets and IEC61162 sentence were applied to exchange data through link between MFD and radio equipments, and additional messages needed for each equipment and function were defined. The integrated MFD monitor is easily operated by the menu method, and the performance of the interface was evaluated by checking the distress and emergency communication functions related to maritime safety and the message transmission status by equipment.