• Title/Summary/Keyword: Network Operation

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Improvement of Encoding Detection Algorithm for Multi-byte Encoded Data with Errors (오류가 발생한 멀티바이트 인코딩 데이터의 인코딩 기법 판별 알고리즘 개선)

  • Bae, Junwoo;Kim, Seonbeom;Park, Heejin
    • The Journal of Korean Institute of Next Generation Computing
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    • v.13 no.2
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    • pp.18-25
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    • 2017
  • In computer science, an encoding is a standardization of converting information to one format for audio, video or text. Therefore, the encoding information of the data should be known to open and read it and there are algorithms detecting encoder of the data. However, some informations of data could be disappeared by packet loss when transmitted on network, especially, if the data is snatched by packet sniffing or eavesdropping from wireless communications. In this paper, we improve the performance of encoding detection algorithm of 'uchardet' program for multi-byte encoded data with errors based on bit-shift algorithm. To simulate the performance, we generated Korean and Japanese text data with errors that is removed some random bits at random positions. Then the detection algorithm are tested using the data and 'uchardet-bitshift' showed better performance than 'uchardet'. When Korean texts are used, 'uchardet' could detect perfectly with ≤0.005% errors but it showed 0% detection rate with ≥1% errors while 'uchardet-bitshift' detected perfectly with ≤0.05% errors and it showed correct detection cases with ≥1% errors. Japanese texts with errors tend to report falsely as Chinese encoding because Japanese texts include lots of Chinese characters. As a results, we improved encoding detection algorithms by applying bit shift operation.

A Development of Optimum Operation Models for Express-Rail Systems (급행열차 도입을 통한 최적운행방안 수립에 관한 연구 - 수도권 광역 도시철도를 중심으로 -)

  • Park, Jeong-Soo;Lee, Hoon-Hee;Won, Jai-Mu
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.26 no.4D
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    • pp.679-686
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    • 2006
  • Recently, the city railway in the Seoul Metropolitan Area (SMA) has offered a low quality of service as a passage time, because it was operated slowly. So, the people who live in modern society are not satisfied about passage time, therefore, this study tried to make that the subway in the SMA becomes a more functional and effective wide-area-transportation-network through an express train introduction's method which examined cases from abroad and current system. and then presented how express train could be applied to current system. In a case study, We used the An-San Line and Su-In Line as a examples and developed a schedule which can minimize the delaying time of subway by using Branch & Bound Algorithm. The train operational plan was loaded to consider a railroad siding, Obtained site, and the dispatch interval(three to ten minutes) for the express and local lines and finally, We presented an alternative operational plan which made by those factors.

The Study on Determination of Benefit Factor as Constructing Traffic Facilities Using ANP (ANP기법을 이용한 교통시설 건설사업의 편익항목 선정에 관한 연구)

  • Kim, Man Kyeong;Jung, Hun Young;Lee, Sang Yong
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.26 no.1D
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    • pp.41-47
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    • 2006
  • The construction of traffic facilities has generated a variety of problems in the equality and efficiency when it would be planed and evaluated. One of the reasons for these phenomena isn't the definition of an objective standard about benefit items. Thus, results of evaluation couldn't give a demonstration of confidence. But, the traffic facility construction and its operation costs are securely appeared. Therefor, it will be demonstrated to decide the benefit items in this study. Before deciding the items, user's satisfaction evaluation and economic analysis would be carried. We find out subway user's satisfaction higher than load traffic mode user in satisfaction evaluation, while subway's economic feasibility is lower than load facility, as a result of B/C analysis. In this inconsistent results, we found out that the benefit value is a little lower because of indefinite standard of it's items as comparing Busan Metropolitan City's population with subway's modal split ratio. Accordingly, we enumerate some benefit items in the case of feasibility evaluation as constructing traffic facility. And each of evaluation items' weight is estimated by using ANP. We found out that the weight value of accessibility has the highest one, that of punctuality has second, that of travel time has third, and benefit items according to improvement of user's traffic condition have much more important than those which were considered in the existence economic analysis.

A Study on the Construction for Optimal Network of Metro Transfer System in Yangsan Area (양산지역 도시철도 환승체계 최적노선망 구축에 관한 연구)

  • Choi, Yang Won
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.30 no.1D
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    • pp.27-36
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    • 2010
  • Recently, the management of metro business in large cities has become more difficult because of increased construction and operation costs. The purpose of this paper presents the construction of transfer system to resolve about recent tendency to decrease of metro-users and diminution of use efficiency which are serious problems of Busan metro. To cope with this situation, it is necessary to examine the methods of obtaining returns on development profits of land value rises that occur due to transfer system construction between Busan metro line #1 and line #2 in Yangsan area. Therefore, it was made use of research on metro utilization to presuppose service improvement, as an alternative, in the transfer system construction between metro and metro which might be powerful influence over metro-users. In this research, it was examined the actual situation of rises in land values brought about by the transfer system construction of metro line #1 and line #2 in Yangsan area with application of four (4) methods, and have calculated a basis of the development profits produced by the transfer system construction of metro line. According to the economical efficiency analysis, the total construction cost amount to 4,827.1 billion won of case #1 based on single track, and evaluate economically as B/C to 1.013, NPV to 72.7 billion, IRR to 5.614 percent.

Policy Implications of the Long-term Care Insurance System Revitalization Process for Establishing Integrated Care System in Japan (일본의 지역포괄케어시스템 구축과 개호보험제도 개정과정의 정책적 시사점)

  • Yoo, Ae Jung
    • 한국노년학
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    • v.39 no.1
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    • pp.1-20
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    • 2019
  • Recently, the Ministry of Health and Welfare has emphasized the necessity to build community care, and the interest of health care- long-term care-social welfare system continues. In order to examine the future vision of long-term care for elderly people, which can be a core system in establishing community models for elderly people in the future, we will implement aging in place as a national policy project. It is meaningful to analyze in depth the case of Japan's policy implementation through the amendment process of long-term care insurance system. The purpose of this study is to examine the concept definition, operating system, and major promotion process of the Integrated Care System in Japan and to suggest policy implications for the future Korea long-term care insurance system. As a result of reviewing the operation status and revision process of the long-term care insurance system for establishing the Integrated care system in Japan, it is necessary to clarify the basic principles and construction of community care system, diversification of residence type and upgrading work, establishment of linkage network of health care-long term care-social welfare, expansion of support for family and self-mind.

Computer vision-based remote displacement monitoring system for in-situ bridge bearings robust to large displacement induced by temperature change

  • Kim, Byunghyun;Lee, Junhwa;Sim, Sung-Han;Cho, Soojin;Park, Byung Ho
    • Smart Structures and Systems
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    • v.30 no.5
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    • pp.521-535
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    • 2022
  • Efficient management of deteriorating civil infrastructure is one of the most important research topics in many developed countries. In particular, the remote displacement measurement of bridges using linear variable differential transformers, global positioning systems, laser Doppler vibrometers, and computer vision technologies has been attempted extensively. This paper proposes a remote displacement measurement system using closed-circuit televisions (CCTVs) and a computer-vision-based method for in-situ bridge bearings having relatively large displacement due to temperature change in long term. The hardware of the system is composed of a reference target for displacement measurement, a CCTV to capture target images, a gateway to transmit images via a mobile network, and a central server to store and process transmitted images. The usage of CCTV capable of night vision capture and wireless data communication enable long-term 24-hour monitoring on wide range of bridge area. The computer vision algorithm to estimate displacement from the images involves image preprocessing for enhancing the circular features of the target, circular Hough transformation for detecting circles on the target in the whole field-of-view (FOV), and homography transformation for converting the movement of the target in the images into an actual expansion displacement. The simple target design and robust circle detection algorithm help to measure displacement using target images where the targets are far apart from each other. The proposed system is installed at the Tancheon Overpass located in Seoul, and field experiments are performed to evaluate the accuracy of circle detection and displacement measurements. The circle detection accuracy is evaluated using 28,542 images captured from 71 CCTVs installed at the testbed, and only 48 images (0.168%) fail to detect the circles on the target because of subpar imaging conditions. The accuracy of displacement measurement is evaluated using images captured for 17 days from three CCTVs; the average and root-mean-square errors are 0.10 and 0.131 mm, respectively, compared with a similar displacement measurement. The long-term operation of the system, as evaluated using 8-month data, shows high accuracy and stability of the proposed system.

A Study on Constructing a RMF Optimized for Korean National Defense for Weapon System Development (무기체계 개발을 위한 한국형 국방 RMF 구축 방안 연구)

  • Jung keun Ahn;Kwangsoo Cho;Han-jin Jeong;Ji-hun Jeong;Seung-joo Kim
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.33 no.5
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    • pp.827-846
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    • 2023
  • Recently, various information technologies such as network communication and sensors have begun to be integrated into weapon systems that were previously operated in stand-alone. This helps the operators of the weapon system to make quick and accurate decisions, thereby allowing for effective operation of the weapon system. However, as the involvement of the cyber domain in weapon systems increases, it is expected that the potential for damage from cyber attacks will also increase. To develop a secure weapon system, it is necessary to implement built-in security, which helps considering security from the requirement stage of the software development process. The U.S. Department of Defense is implementing the Risk Management Framework Assessment and Authorization (RMF A&A) process, along with the introduction of the concept of cybersecurity, for the evaluation and acquisition of weapon systems. Similarly, South Korea is also continuously making efforts to implement the Korea Risk Management Framework (K-RMF). However, so far, there are no cases where K-RMF has been applied from the development stage, and most of the data and documents related to the U.S. RMF A&A are not disclosed for confidentiality reasons. In this study, we propose the method for inferring the composition of the K-RMF based on systematic threat analysis method and the publicly released documents and data related to RMF. Furthermore, we demonstrate the effectiveness of our inferring method by applying it to the naval battleship system.

Research on Security System for Safe Communication in Maritime Environment (해상환경에서 안전한 통신을 위한 보안체계 연구)

  • Seoung-Pyo Hong;Hoon-Jae Lee;Young-Sil Lee
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.23 no.5
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    • pp.21-27
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    • 2023
  • As a means of helping ships navigate safely, navigational aids in operation in the maritime envirionment require periodic management, and due to the nature of the environment, it is difficult to visually check the exact state. As a result, the smart navigation aid system, which improves route safety and operational efficiency, utillizes expertise including sensors, communications, and information technology, unlike general route markings. The communication environment of the smart navigation aid system, which aims to ensure the safety of the navigators operating the ship and the safety of the ship, uses a wireless communication network in accordance with the marine environment. The ship collects the information necessary for the maritime environment on the land and operates. In this process, there is a need to consider the wireless communication security guideline. Basically, based on IHO S-100 a standard for facilitating data exchange and SECOM, which provides an interface for safe communication. This paper research a security system for safe communication in a maritime environment. The security system for the basic interface based on the document was presented, and there were some vulnerabillties to data exchange due to the wireless communication characteristics of the maritime environment, and the user authetication part was added considering the vulnerability that unauthorized users can access the service.

Very Short- and Long-Term Prediction Method for Solar Power (초 장단기 통합 태양광 발전량 예측 기법)

  • Mun Seop Yun;Se Ryung Lim;Han Seung Jang
    • The Journal of the Korea institute of electronic communication sciences
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    • v.18 no.6
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    • pp.1143-1150
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    • 2023
  • The global climate crisis and the implementation of low-carbon policies have led to a growing interest in renewable energy and a growing number of related industries. Among them, solar power is attracting attention as a representative eco-friendly energy that does not deplete and does not emit pollutants or greenhouse gases. As a result, the supplement of solar power facility is increasing all over the world. However, solar power is easily affected by the environment such as geography and weather, so accurate solar power forecast is important for stable operation and efficient management. However, it is very hard to predict the exact amount of solar power using statistical methods. In addition, the conventional prediction methods have focused on only short- or long-term prediction, which causes to take long time to obtain various prediction models with different prediction horizons. Therefore, this study utilizes a many-to-many structure of a recurrent neural network (RNN) to integrate short-term and long-term predictions of solar power generation. We compare various RNN-based very short- and long-term prediction methods for solar power in terms of MSE and R2 values.

A Design of Authentication Mechanism for Secure Communication in Smart Factory Environments (스마트 팩토리 환경에서 안전한 통신을 위한 인증 메커니즘 설계)

  • Joong-oh Park
    • Journal of Industrial Convergence
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    • v.22 no.4
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    • pp.1-9
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    • 2024
  • Smart factories represent production facilities where cutting-edge information and communication technologies are fused with manufacturing processes, reflecting rapid advancements and changes in the global manufacturing sector. They capitalize on the integration of robotics and automation, the Internet of Things (IoT), and the convergence of artificial intelligence technologies to maximize production efficiency in various manufacturing environments. However, the smart factory environment is prone to security threats and vulnerabilities due to various attack techniques. When security threats occur in smart factories, they can lead to financial losses, damage to corporate reputation, and even human casualties, necessitating an appropriate security response. Therefore, this paper proposes a security authentication mechanism for safe communication in the smart factory environment. The components of the proposed authentication mechanism include smart devices, an internal operation management system, an authentication system, and a cloud storage server. The smart device registration process, authentication procedure, and the detailed design of anomaly detection and update procedures were meticulously developed. And the safety of the proposed authentication mechanism was analyzed, and through performance analysis with existing authentication mechanisms, we confirmed an efficiency improvement of approximately 8%. Additionally, this paper presents directions for future research on lightweight protocols and security strategies for the application of the proposed technology, aiming to enhance security.