• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.11 no.2
• /
• pp.469-475
• /
• 2010

The railway signalling system plays an essential role in the safe and efficient train operation as serving control functions of train operation intervals and train routes. The reliability and safety of the system are very important because the failure of the railway signalling system can lead to train collision or derailment as well as train operation stop. Until now, in railway signalling system the conventional wayside signal mode has been used generally. There are, however, the risk of accidents such as human mistakes caused by that the driver identifies the signal lamp status and controls train speed with the naked eye. It is also necessary to refurbish the obsolete system. Thereby, It is being effective that the onboard signal mode has been recently introduced and applied in order to transmit the speed control information to train by using the computer and communication equipment. It is necessary to switch over the system in a way while providing passengers with an operation service to replace the obsolete signal system. In this paper, we verify the cases through trial assessment which are solved by the way of adding specific functionalities in the problems of interference among the procedure of switch-over processes and a serial of processes for system verification while a train is operated in the new system in parallel to the existing system.

• Journal of the Korean Society of Marine Environment & Safety
• /
• v.26 no.2
• /
• pp.129-138
• /
• 2020

This study recognizes problems in the current system of providing navigation safety information (NSI), which is centered on merchant ships, to prevent maritime accidents of fishing boats and small vessels in coastal areas. The system proposed in this study is an effective method of providing NSI to support the safe navigation of small vessels such as fishing boats. First, the status and characteristics of recent maritime accidents were examined, and NSI service targets were identified. Second, the limitations of the current NSI system were determined, and measures were proposed to establish an NSI Integrated Platform (NSIP) that ensures the integration, accessibility, and usability of NSI for a substantial portion of the public. Third, to utilize the NSIP, various NSIs are applied as additional information for the electronic chart system used in the e-navigation ship terminals being developed in connection with the Korean e-navigation project. Functions that set the audiovisual alarm function to automatically operate when a ship enters a navigation risk zone is proposed. These functions are technically achieved by reviewing expert opinions of related organizations and professional producers. The results of this study suggest that NSI can be applied to small vessels such as fishing boats, through the Korean e-Navigation project, to prevent maritime accidents caused by the human error of navigators.

• Journal of KIISE:Computer Systems and Theory
• /
• v.37 no.4
• /
• pp.205-214
• /
• 2010

BPEL is a standard workflow language, which interacts with Web Services and is used in various applications. But it is difficult to use BPEL for specific applications which require additional functions. In this paper, we present a system which can add new functions to BPEL based on an aspect-oriented programming (AOP) technique. In order to add new functions to BPEL, we define a JWX document format that can describe new functions to apply to BPEL. JWX is XML-oriented document that can code the corresponding Java program in order to dynamically add new functions to BPEL documents. It is possible for BPEL workflow to add new functions without modifying the existing programs using the AOP technique, which guarantees low degree of coupling between key and additional requirements. Additionally this systems weaves based on new functions of Java program and JWX document by expanding BPEL engine called B2J based on AOP and execute them. Therefore it is possible to develop a new BPEL engine with additional functions easily and with low cost. The new system can execute additional conditions that the current BPEL engine doesn’t provide. The new system using functions of BPEL supplied by B2J. The new system can be used to add a new rule engine, which isn't currently provided.

• Journal of Korea Port Economic Association
• /
• v.36 no.3
• /
• pp.75-98
• /
• 2020

This study explores the incentive system in Korean ports to become a global logistics hub in Asia or to be competitive among Korean ports as a regional hub. First, we identified the types of port incentives in Korea and in overseas ports. We selected potential incentives applicable to Korean ports and compared whether they were meaningful, efficient, and effective in the short and long term. We selected IPA (Importance-performance Analysis) as an analytical method and surveyed users and experts. The results show that it is necessary and effective to provide incentives for new shipping companies, both export and import shippers, while setting criteria for reasonable incentives. Factors needed for improvement included simplifying and calculating the incentive request process, incentives for terminal operators, and new incentives, in addition to existing incentives. Policy-making organizations will also need to collect feedback on institutional improvements and raise awareness among users. Key factors for improvement include providing incentives for existing shipping companies. In particular, in order to actively manage systematic and efficient policies, incentive criteria for existing shipping companies need to be reconsidered.

• Journal of the Korea Convergence Society
• /
• v.11 no.1
• /
• pp.237-246
• /
• 2020

The background of the research is the following: As a result of ultra-light flying device industry development, the utilization of drones and their efficiency have been increasing. However, problems regarding flight permission·approval procedure have not been improved, resulting in increased number of civil complaints. Thus, the purpose of this research is to minimize such civil petition according to the required standards of the two government organizations through enhancing the procedure for managing and employing the system. The research methods entail pinpointing the problems by analysing ultra-light flying device related literature review and by holding focus-interviews with field experts, thereby verifying and providing improved solutions. Under (MLIT) Ministry of Land, Infrastructure and Transport supervision and in accordance with aviation security law, the research provides various updated functions such as improved civil petition processing system's employment and management system, flight approval, integration of names, process, format regarding aviation photographing approval, tool buttons such as the 'Main' button in the system's homepage. This research has the following expected effects : Firstly in the law and regulations section, the clear distinction in the missions and roles of each organization enhances cooperations in tackling civil petition. Secondly the integration of civil petition process reduces time and improves efficiency. And lastly, the improvement of supplementary tools for the public is expected to minimize civil petitions. Future research needs to be conducted under the supervision of the Ministry of National Defense(MND). Factors such as systematic infrastructure for flight photography approval, related unit's reorganization following the defense reform 2.0, and guaranteed conditions for field security action units need to be ameliorated.

• The Journal of Small Business Innovation
• /
• v.19 no.3
• /
• pp.1-16
• /
• 2016

Korean government had used public 'credit guarantee schemes' (CGS) as a counter-cyclical measure. However, it is still controversial about the effectiveness of policy financing on the SMEs. Criticism on policy financing involves the argument that supporting enterprises hampers competition and innovation of SMEs by increasing their dependence on the government and delays the exit of marginal firms. In this paper, we investigate how to effectively build up the rationale of running public CGSs. At the same time, we propose the ways to coexist of public credit guarantee and market-based private finance system for SMEs. First, CGS, as a counter-cyclical function, must coexist with the private financial system by compensating the market failure caused by pro-cyclical behavior of the private financial market. Second, CGS has the comparative advantages, compared to both the interest rate policy of the central bank and fiscal policy of the government. The credit guarantee is the symptomatic treatment that could revitalize the economy shortly by providing liquidity. Also, knowing that CGS is provided based on the leverage ratio defined by outstanding guarantee divided by capital fund, public 'credit guarantee' (CG) has an advantage that is free from the risk of government deficit. Third, the reason for existence of the CGS should be founded in supporting services for SMEs, available only in a public sector that is difficult to expect from private banks. In this regard, it is desirable to strengthen the publicness of credit guarantee over the support for start-ups, growing companies, the improvement of productivity, increase of exports, a long-term investment in facilities, the employment-creating businesses, and innovative enterprises.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
• /
• v.7 no.3
• /
• pp.65-73
• /
• 2012

Microfinance has been an important tool for the economic growth and poverty alleviation. But the success factors and risk factors have not been synthesized in academic literature. This article has paid attention to success factors and potential risk of the Grameen Bank. Grameen Bank methodology is almost the reverse of the conventional banking methodology. Conventional banking is based on the principle that the more you have, the more you can get. Founder of Grameen Bank, Professor Yunus pointed out that, "The least you have the highest you have the priority to receive a loan". On the basis of theoretical literature, there have been different kinds of success factors of microfinance observed in this paper. Key success factors of Grameen Bank are like these: innovation, strict administrative structure, adaptation and learning practice, incentive system. Complementary services such as business consulting and brokerage will contribute to borrowers' economic performance development.

• The Journal of The Korea Institute of Intelligent Transport Systems
• /
• v.9 no.6
• /
• pp.22-32
• /
• 2010

Increasingly advanced Information Technology (IT) has changed the operator so as to create more diversified and advanced traffic information demand. To deal with the changing demand in private sector, a concept of on-demand traffic information has been rapidly introduced. However VMS, a product of the first generation of ITS, which was designed to provide the unspecified individuals during driving the car with the basic level of traffic information by the public failed to actively change itself in such a changing pattern. This study was intended to describe the VMS system (tentatively, FM-VMS) which was further developed to accommodate the needs favoring the sophisticated PDA with the public role of providing the unspecified individuals with the equal information. FM-VMS introduced in this study is the device designed to transmit the voice and message to the drivers through the radio information device mounted on a car. A core technology is, unlike FM-DARC and RDS, the Water Making technology which directly inserts the digital signal into FM frequency in use. It's been currently used for broadcasting and security purpose. A detection rate as a result of testing FM-VMS system using Water Making technology was 90% or more in voice and message within 20m from test VMS. When a public-developed VMS information could be transmitted using FM frequency to the relatively vulnerable users (vulnerable to traffic information) in voice on a real-time basis to provide the regional traffic information, and furthermore, VMS message could be received through radio liquid using FM frequency only, it would obviously bring about the innovation in ITS as well as pave the way for creating the new added value down the road.

• Journal of the Institute of Electronics and Information Engineers
• /
• v.52 no.3
• /
• pp.39-47
• /
• 2015

In this paper, we propose a new time synchronization algorithm using CoAP(constrained-application protocol) in sensor network environment, which handles a technique that synchronizes an explicit timestamp between sensor nodes not including an additional module for time-setting and sensor node gateway linked to internet time server. CoAP is a standard protocol for sensor data communication among sensor nodes and sensor node gateway to be built much less memory and power supply in constrained network surroundings including serious network jitter, packet losses, etc. We have supplied an exact time synchronization implementation among small and cheap IP-based sensor nodes or non-IP based sensor nodes and sensor node gateway in sensor network using CoAP message header's option extension. On behalf of conventional network time synchronization method, as our approach uses an exclusive protocol 'CoAP' in sensor network, it is not to become an additional burden for synchronization service to sensor nodes or sensor node gateway. This method has an average error about 2ms comparing to NTP service and offers a low-cost and robust network time synchronization algorithm.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.25 no.11A
• /
• pp.1661-1671
• /
• 2000

본 고에서는 한국통신(Korea Telecom) IMT-2000 시험시스템(이하: Trial system 라고 함) 단말기용 전력증폭단으로 적용하기 위한 다단구동증폭기 및 전력증폭기를 GaAs MMIC로 설계 구현하는 기술을 제시하였다. 설계된 구동증폭기는 3단으로구성하여 RF(Radia Frequency) 송신신호(1955$\pm$70MHz)대역에서 2단 (중간단)의 이득 조정범위가 40 dB이상이 될 수 있도록 능동부품인 MESFET를 Cascade 형으로 구성하고 MESFET의 게이트(gate)에 조정전압을 인가하는 증폭기를 설계하여 GaAs MMIC화 1 침(크기4$\times$5 mm)으로 제작하였다. 아울러, 본 논문에서는 제시한 구동증폭기는 동작주파수 대역폭 범위기 3.5배이고 출력전력은 15dBmm 이며, 출력전력이득이 25~27dB이고 반사계수는 -15~20dB이며 이득평탄도 3dB(동작주파수 대역폭내)로써 Trial system용 단말기의 최종단인 전력증폭단의 출력단 특성을 효과적으로 나타내었다. 그리고, 전력 증폭기는 2개의 입력단에서 출력되는 신호를 분배하는 전력분배기와 병렬구조인 4개의 증폭단에서 출력되는 출력신호를 외부에서 접속하는 전력결합기를 접소하여 구성하였으며 RF(Radio Frequency) 주파수(1955 $\pm$70NHz)에서 대역폭을 4배로 설계하여 광대역인 대역폭을 구현하였고 출력전력은 570mW이며, 출력부가효율(PAE; Power Added Efficency)가 -15$\pm$20dB이고, 이득 평탄도(Gain flatness)는 동작주파수 대역내에서 0.5dB이며 입출력 전압정재파비(Input & Output VSWR)가 13이하인 고출력 전력증포기를 GaAs MMIC화 1칩 (크기; 3$\times$4mm)으로 제작하였다.의 다양성이나 편리성으로 변화하는 것이 국적을 바꾸는 것보다 어려운 시 대가 멀지 않은 미래에 도래할 것이다. 신세기 통신 과 SK 텔레콤에는 현재 1,300만명이 넘 는 고객이 있으며. 이들 고객은 어 이상 음성통화 중심의 이동전화 고객이 아니라 신세기 통신과 SK텔레콤이 함께 구축해 나갈 거대란 무선 네트워크 사회에서 정보화 시대를 살아 갈 회원들이다. '컨텐츠의 시대'가 개막되는 것이며, 신세기통신과 SK텔레콤은 선의의 경쟁 과 협력을 통해 이동인터넷 서비스의 컨텐츠를 개발해 나가게 될 것이다. 3배가 높았다. 효소 활성에 필수적인 물의 양에 따른 DIAION WA30의 라세미화 효율에 관하여 실험한 결과, 물의 양이 증가할수록 그 효율은 감소하였다. DIAION WA30을 라세미화 촉매로 사용하여 아이소옥탄 내에서 라세믹 나프록센 2,2,2-트리플로로에틸 씨오에스터의 효소적 DKR 반응을 수행해 보았다. 그 결과 DIAION WA30을 사용하지 않은 경우에 비해 반응 전환율과 생성물의 광학 순도는 급격히 향상되었다. 전통적 광학분할 반응의 최대 50%라는 전환율의 제한이 본 연구에서 찾은 DIAION WA30을 첨가함으로써 성공적으로 극복되었다. 또한 고체 염기촉매인 DIAION WA30의 사용은 라세미화 촉매의 회수 및 재사용이 가능하게 해준다.해준다.다. TN5 세포주를 0.2 L 규모 (1 L spinner flask)oJl에서 세포간의 응집현상 없이 부유배양에 적응,배양시킨 후 세포성장 시기에 따른 발현을 조사한 결과 1 MOI의 감염조건 하에서는 $0.6\times10^6$cell/mL의 early exponential시기의 세포밀도에서 72시간 배양하였을 대 최대 발현양을 나타내었다. 나타내었다. $\beta$4 integrin의 표현이 침투 능력을 높이는 역할을 하나 이때에는 laminin과 같은 리간드와의 특이