• Proceedings of the KSR Conference
• /
• 한국철도학회 2010년도 춘계학술대회 논문집
• /
• pp.810-815
• /
• 2010

Since a long time ago, many railway engineers analyze and discuss the interface between the sub-system of railway, such as a wheel/rail interface, pantograph/catenary interface etc. The verifying of the system interface could help to achive the optimized performance and safety of the railway system considering that the railway system is constructed by various engineerings, such as civil, mechanical, electrical, etc. A rolling stock with distributed drive system, which will be developed by HEMU-400x project, is capable of running on high speed line and conventional line in Korea. To verify the performance of rolling stock, test run will be done with revenue service line. And the test items of the system interface have to be selected to verify a functional compatibility and physical force between rolling stock and infrastructure. In this paper, the authors will indicates the test items to verify system interface. To achive the conclusion, the authors analyze a specification of the development train and the design value of Seoul-Busan high speed line, which will be used for testing of the development train, and also, study the various case of high speed train commissioning.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 한국정보통신학회 2017년도 춘계학술대회
• /
• pp.87-89
• /
• 2017

In this paper, we propose a multi-band network selection (MNS) system, which determines and seamlessly connects to the desired available communication band based on user preferences and network environments. The MNS system employs MNS server in the middleware layer which communicates with clients in order to combine and manage heterogeneous networks efficiently. In addition, we define a system architecture and function modules of the MNS system. The MNS system monitors availability in each communication band and updates the network status information table which is applied to determining the best available network. It is expected that the MNS system can be applied to the next generation maritime networks and communication infrastructure of e-navigation.

• The Journal of Society for e-Business Studies
• /
• 제14권3호
• /
• pp.1-13
• /
• 2009

EAI(Enterprise Application Integration) as an infrastructure of application integration had played an important role for many companies to make epochal changes, expense reduction, and new application services. The continuous monitoring and management of data covering whole environment of system operations should be well-supported so that the data consistency and system stability are guaranteed to implement and operate the services effectively. In this paper, the requirements and functions of monitoring system are defined for the stable EAI service. An actual web-based system is designed and implemented. This web-based monitoring system is broadly applicable to general EAI environments.

• Physical Therapy Rehabilitation Science
• /
• 제11권4호
• /
• pp.571-578
• /
• 2022

Objective: Cognitive-motor trainings had a positive impact on cognitive function and dual-task trainings led to improvements of global cognitive function. The brain activity of the prefrontal cortex (PFC) is another indicator that can infer cognitive function. This study aims to confirm the usability of the interactive system cognitive-motor training program and the changes in the prefrontal cortex through training. Design: Cross-sectional study Methods: In this study, two cognitive tasks were randomly applied to 20 adults as cognitive-motor training using an interactive system, and the same task was performed using the original method. During all tasks, the brain activity of the prefrontal cortex was measured by the change in oxyhemoglobin (HbO) in real-time using Functional Near-Infrastructure. After performing the tasks, the usability of the developed interactive system was evaluated by a usability questionnaire which consists of five items, and each item consists of a 7-point Likert scale that responds from 1 point to 7 points. Results: The HbO levels were increased during cognitive task performance than at the resting phase. And evaluating the usefulness of the interactive system, a questionnaire result showed that it would be useful for cognitive-motor programs. Conclusions: The cognitive-motor training using the interactive system increased the activity of the prefrontal cortex, and the developed wearable sensor-based interactive system confirmed its usefulness.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• 제19권9호
• /
• pp.269-278
• /
• 2018

In Korea, BIM technology is applied mainly to building construction projects, but is expected to be applied rapidly to civil engineering projects because the government is currently considering the mandatory application of BIM for infrastructure facilities. Because the infrastructure project is processed in a horizontal work area, the application of BIM technology is more useful in the schedule management of the construction phase than the interference management of the design phase. The 4D CAD system is a typical BIM technology applied to the schedule management in the construction phase, but the application to the actual project is limited due to the lack of practical functions. This study examined the functions of four representative 4D CAD systems commercialized so that the selection criterion can be provided according to the characteristics of the project, and suggests that the functions that should be improved to have practicability. As a result of functional analysis, the application characteristics of each system were analyzed and the user convenience was suggested. In addition, a linear 4D simulation methodology was developed to improve the functions applicable to civil engineering projects, and ways to improve the utilization of the infrastructure projects as the construction phase BIM were suggested. In railway and road construction projects, most activities, such as earthwork, bridges, and tunnels proceed along the distance axis in a horizontal space. Therefore, a linear 4D simulation method, in which an activity is expressed along a distance axis, can be more practically useful rather than a simple 4D simulation method with a Gantt chart.

• Korean Journal of Computational Design and Engineering
• /
• 제10권5호
• /
• pp.356-364
• /
• 2005

As a ritual of modern people is getting higher, the safety assessment of the structure related to people has become the most important part in the process of the design. Especially, in the case of a ship, as regulations about the safety of passengers and the pollution in the ocean are strictly reinforcing, the safety assessment has become the most important part in the process of the design. However, because the established safety assessment is mostly depend on the experienced theory, it is so difficult to assess the safety considering a lot of situations such as various ocean environments, the mistake of sailors and emergency situations. As the way to solve this problem, lately the study of the simulation using a computer has been processed. In this paper, we suggested network-based simulation system framework using HLA (High Level Architecture) among many kind of simulations to assess the safety of the ship. Because HLA has already become a standard of the future simulation system in the U.S. DoD(Department of Defense) and Korea army, we expect to raise the possibility in the future. In addition, because HLA makes a standard of documents and a reused component(Federate) of simulation(Federation) by OMT(Object Model Template) and RTI(Runtime Infrastructure), we expect that this study will be developing the safety assessment of ship as well as operation in warship and cooperation with another applications.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• 제38C권2호
• /
• pp.155-164
• /
• 2013

Two design techniques for more accurate and more convenient hybrid positioning system with visible light communication (VLC) and ad-hoc wireless network infrastructure are proposed, in order to overcome the problems of high estimation error, high cost, and limited service range of the conventional positioning techniques. First method is based on a non-carrier VLC based hybrid positioning technique for applications involving of low data rate optical sensing and narrow-range visible light reception from transmitter, and long-range positioning. The second method uses a 4 MHz carrier VLC-based hybrid positioning technique for a high data rate optical sensing and wide-range visible light receiving from transmitter, and mid-range positioning applications. In indoor environments with obstacles where there are long-range 7731.4cm and mid-range 2368cm distances between an observer and a target respectively, the hybrid positioning developed with two design techniques are tested, and the proposed system is verified and analyzed in this paper.

• The Journal of Engineering Geology
• /
• 제34권1호
• /
• pp.39-49
• /
• 2024

The construction of underground infrastructure is garnering growing increasing research attention owing to population concentration and infrastructure overcrowding in urban areas. An important associated task is establishing a monitoring system to evaluate stability during infrastructure construction and operation, which relies on developing techniques for ground investigation that can evaluate ground stability, verify design validity, predict risk, facilitate safe operation management, and reduce construction costs. The method proposed here uses satellite imaging in a cost-effective and accurate ground investigation technique that can be applied over a wide area during the construction and operation of infrastructure. In this study, analysis was performed using Synthetic Aperture Radar (SAR) data with the time-series radar interferometric technique to observe surface displacement during the construction of urban underground roads. As a result, it was confirmed that continuous surface displacement was occurring at some locations. In the future, comparing and analyzing on-site measurement data with the points of interest would aid in confirming whether displacement occurs due to tunnel excavation and assist in estimating the extent of excavation impact zones.

• Proceedings of the KIEE Conference
• /
• 대한전기학회 2004년도 학술대회 논문집 정보 및 제어부문
• /
• pp.89-91
• /
• 2004

In SCADA systems, an RTU is a device installed at a remote location that collects data, codes the data into a format that is transmittable and transmits the data back to a central station, or MTU. An RTU also collects information from the master device and implements processes that are directed by master device. RTUs are equipped with input channels for sensing or metering, output channels for control, indication or alarms and a communications port. In general, the data are transmitted via a wired communication infrastructure such as RS422 or RS485 between RTU and MTU. But, limited range of wired communication doesn't allow the system to cover remote areas over the limitation, and building a wired communication network is not easy in the circumstances. In this Paper, we design and implement a smart cost-effective Web-RTU that can communicate with MTU via Web. Web is of benefit to the Web-RTU, because it is not only free from the distance limitations, but also is built easily and cost-effectively wherever Internet resources are available. Additionally, Web can be easily applied to the SCADA system with the development of hardware and software for communications. The Web-RTU has a program memory, a data memory and a RAM inside, and uses Atmega128, low-cost 8 bit micro-processor with eight AI(Analog Input). It performs well enough to implement all existing roles of RTU.

• Journal of the Korean Society for Aeronautical & Space Sciences
• /
• 제42권12호
• /
• pp.1073-1079
• /
• 2014

Aircraft parts are considered as a significant element for the continued airworthiness of the certified aircraft well as a partial component consisting of the new aircraft design. US FAA established the certification system of Parts Manufacturer Approval in 1965, which is contributing to the continued airworthiness of the aircraft in operation and to the expansion of worldwide market of aircraft parts. In this paper, we compared the differences of the certification systems between FAA Parts Manufacturer Approval and EASA European Part Approval, and proposed the rulemaking items to improve Korean Parts Manufacturer Certification System and to contribute to growth of aircraft parts industry.