• Proceedings of the Korean Geotechical Society Conference
• /
• 2000.11a
• /
• pp.737-744
• /
• 2000

This paper resorts to rock mass rating and rock mass quality to draw value based on the evaluation of rock and to draw interrelation formula in relation to rock mass quality, A comparative analysis was given of survey values reported in the existing documents. This paper has tried to find out the relationship between RMR and Q System for the sake of choosing rational reinforcing patterns and of the safety of tunnels. The results run as follow: RMR=8.251n(Q)+43.83. This paper has also tried to find out the relationship between RMR and Q System by using Fuzzy Approximate Reasoning Concept. We suggest that those in charge should not depend on a single system only after evaluating the classification of rocks, and compare one result with another for the good of keeping track of the condition of base rocks in a better way.

• Proceedings of the KSR Conference
• /
• 2007.05a
• /
• pp.692-697
• /
• 2007

The current collection system, pantograph, is one of the important subsystems in electric train system, because of it's fatal function and role of supplying power to the train system. Generally, the function of current collection system is evaluated by loss of contact rate between pantograph and contact wire in catenary by measuring arcs, or by statistical method of evaluating minimum mean contact force. The Korean Tiling Train(TTX) has been manufactured by KRRI and Korean domestic companies and is preparing the trial running test of itself. In this paper, we introduce our successful achievement, measuring system and applied methods of dynamic characteristics for the tilting pantograph, developed of by our own technology.

• Proceedings of the KOSOMBE Conference
• /
• v.1998 no.11
• /
• pp.213-214
• /
• 1998

The important role of the ultrasonic Doppler system in the modem clinical medicine is to provide the clinical information of the vascular system. The ultrasonic pulsed wave(PW) Doppler system, a kind of the ultrasound Doppler system, is more available than the ultrasonic continuous wave(CW) Doppler system because it can evaluate the velocity and the direction of blood flow as well as the depth of vessel. However, the ultrasonic PW Doppler system has the disadvantage that the range of evaluating velocity of blood flow is limited(Nyquist limit). In order to solve this limit, we propose the algorithm for eliminating this aliasing in this paper. In addition, we propose the efficient signal processing algorithm.

• Journal of Industrial Technology
• /
• v.14
• /
• pp.77-87
• /
• 1994

This research is an experimental work of investigating the behavior of soil nailing system under surcharges whereas most of them were concentrated on evaluating its capacity under selfweight of excavated ground. Model tests in laboratory were performed to investigate the ultimate bearing capacity of soil nailing system under surcharges in forms of strip loading. Tests were carried out to find parameters controlling its capacity such as length of nail, vertical and horizontal spacings between nails, inclination of nail installation, and loading position of surcharges. Failure mechanism of forming failure line due to surcharge to soil nailing system was also observed by using dyed sand and monitoring its behavior. From results of these test, effects of parameters was analyzed qualitatively. Thus, this experimental results could provide meaningful data to analyze and design this system later.

• 한국방재학회:학술대회논문집
• /
• 2008.02a
• /
• pp.537-540
• /
• 2008

This paper reviews the operation standards and manuals of earthquake monitoring system for Gyungbu high speed railroad. The domestic earthquake monitoring system detects the acceleration data at the locations of lower part of pier and deck of viaducts and bridges, not like foreign system to do the surface ground accelerations. For the purpose of evaluating the behaviors of the domestic earthquake monitoring system, measured acceleration data on the Odaesan earthquake at Iwon viaduct were analysed. The values of maximum acceleration level of the viaduct were increased from 0.0089g(EW component) of the lower part of pier to 0.014g(EW component) on the deck of the viaduct. And also the predominant periods and frequencies were analysed by the frequency domain analysis.

• Journal of Korea Multimedia Society
• /
• v.20 no.5
• /
• pp.791-799
• /
• 2017

With the development of the internet of things, sensor and device are can be applied to various scenario. Overall improving of the dependability index of internet of things is the ultimate goal. And reliability aims to increase the success rate of internet of things service delivery. Many studies about internet of things system have been made on the system to assess a dependability for providing reliable service to user, but it has difficult to reflect the user context for evaluating the device reliability. Also, most do not consider the availability of content information. In this paper, it proposed dependable device searching system in the internet of things environment. This system evaluates device dependability based on device status and measured data. Through the proposed system, it can be provided reliable context information for user-centric service.

• International Journal of Railway
• /
• v.3 no.1
• /
• pp.34-37
• /
• 2010

In recent, the railway system consists of subsystems as rolling stock and infrastructures as signaling, telecommunication, power supply, overhead contact and platform screen door, etc. Furthermore, each subsystem has complicated interface so as not to understand these relationship. Consequently, to operate the railway system continuously with required safety and availability, the failure data should be corrected and analyzed systematically during operation. To achieve this object effectively, this paper presents the method which is evaluating the operational risk quantitatively using failure data, and selecting the critical equipment. Following this analysis, the improvement plan is established and applied to reduce the operational risk on system or equipment. From this study, the critical equipments of system could be determined and prioritized by risk analysis. Also, the effective maintenance to prevent critical failure could be implanted by this suggested methodology.

• Journal of Korean Institute of Architectural Sustainable Environment and Building Systems
• /
• v.12 no.6
• /
• pp.606-617
• /
• 2018

Increased density of racks has resulted in increased use of data center cooling energy and the needs for energy efficient cooling systems has increased. In response to these needs, ASHRAE presented a performance indicator, which is Mechanical Load Component (MLC), for the purpose of evaluating systems at the design stage. However, the MLC metrics presented in the current standard can only be determined for system compliance and compared alternative systems with the system configuration completed. Therefore, there are limitations to considering MLC from the early stages of design. In this study, to extend the scope of application of MLC in the design phase, the design factors of the main equipment comprising the cooling system are classified by the MLC load component and interrelations between design factors were identified.

• The KIPS Transactions:PartD
• /
• v.15D no.2
• /
• pp.271-284
• /
• 2008

Self-healing is an approach to evaluating constraints defined in target system and to applying an appropriate strategy when violating he constrains. Today, the computing environment is very complex, so researches that endow a system with the self-healing's ability that recognizes problem arising in a target system are being an important issues. However, most of the existing researches are that self-healing developers need much effort and time to analyze and model constraints. Thus, this paper proposes an automated approach to determine problem arising in external and internal system environment. The approach proposes: 1) Specifying the target system through the models created in design phase of target system. 2) Automatically creating constraints for external and internal system environment, by using the specified contents. 3) Deriving a dependency model of a component based on the created internal state rule. 4) Translating the constraints and dependency model into code evaluating behaviors of the target system, and determinating problem level. 5) Monitoring an internal and external status of system based on the level of problem determination, and applying self-healing strategy when detecting abnormal state caused in the target system. Through these, we can reduce the efforts of self-healing developers to analyze target system, and heal rapidly not only abnormal behavior of target system regarding external and internal problem, but also failure such as system break down into normal state. To evaluate the proposed approach, through video conference system, we verify an effectiveness of our approach by comparing proposed approach's self-healing activities with those of the existing approach.

• Journal of the Korean Society for Library and Information Science
• /
• v.32 no.4
• /
• pp.53-67
• /
• 1998

This article investigates the potentialities of using empirical variables and their associated statistical relationships in document representation and retrieval. To this end, a newly devised empirical fact retrieval system was evaluated in comparison to a simulated traditional retrieval system involving a set of predetermined empirical queries. Results indicate that the EFRS generally outperformed the TRS in terms of the precision, search effort, and measures of user satisfaction.