• Journal of the Korean Society for Railway
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• v.10 no.4
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• pp.438-443
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• 2007

This paper proposes an integrated SE process for the development of railway systems with safety assessment included. Although the safety assessment process must be performed with SE process properly with good coordination, the interfaces between the two processes have not been clear. Thus, in many of safety critical system developments in Korea, it is difficult to assess safety in proper development phase. The process model proposed in this paper is based on both the concept of system life cycle and the repetitive use of SE process. In each of development phases, appropriate safety assessment methods are described. Also the evaluation of the integrated system incorporating safety factors is described. The resultant process model is expressed by the Enhanced Functional Flow Block Diagram (EFFBD) using a CASE tool. The model also allows timeline analysis for identifying activity flow and data flow, resulting in the effective management of process. In conclusion, the integrated process enable both the SE process and safety assessment process to cooperate with each other from early development phase throughout the whole system life cycle.

• Journal of Welding and Joining
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• v.16 no.2
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• pp.84-92
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• 1998

On this study, the variations of hardness and microstructure were observed at he spot-welded part of 5182 alminum alloy sheets with thickness of 1.2 mm. The hardness of spot-welded part of aluminum alloy indicated the lowest value at nugget center. Also, the position where fatigue crack exists was investigated by surveying microstructure of the spot-welded sections. Mean load-deformation diagrams were obtained from static tensile test. Fracture was occurred completely within 5 mm after transforming elastic into plastic area. Fatigue test was stopped when the specimens of fatigue test had the final displacement of 0.2mm and measured fatigue bending angle and crack length. This study utilized them, investigated the relations between fatigue bending angle and fatigue crack length and made a estimation of the fatigue fracture life of resistance spot welded part of 5182 aluminum alloy sheet. The relative equation o fatigue crack length and fatigue failure life can be represented by {TEX}$L_{C}${/TEX}=α{TEX}$N_{f}^ {β}${/TEX}.

• Journal of the Korean association of regional geographers
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• v.12 no.5
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• pp.583-594
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• 2006

Relics are life traces of ancestors, and they are good data for giving an idea about space locations of that period. This study classifies relics according to their type, and for each classified group metrical analysis is carried out using GIS and triangle diagram. The criteria used for analysis of relics' locations are elevation, road accessibility and water accessibility. The analysis results show that every relic has its own distribution characteristics according to the time and the type. This means high possibility of approaching a geographical focus on relics distribution and location. While historical period was taking over prehistorical, relics locations moved from the points of great usage water supply possibility to the points of great traffic accessibility. Also, relics of the ruling class for each time period generally have good locations.

• The Korean Journal of Emergency Medical Services
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• v.6 no.1
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• pp.27-37
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• 2002

The health and medical service attracts more public attention as the economy of Korea is rapidly growing up and the standard of living is elevated. Especially, the interest and demand on the prehospital emergency medical service that consists of the important part of primary medical service that is directly related to the life of patients are gradually increased. However, as compared with other advanced countries such as America in this area, Korea actually fell behind in the utilization of IT (Information Technology) to maximize the efficiency of emergency service system as well as has a problem in the general service system. This study suggested the necessity to introduce EMD (Emergency Medical Dispatch) system that takes a great role as the core part in the prehospital emergency medical service that is not systemized in Korea yet. In addition, this study proposed the implementation model of EMD ASP system using ASP (Application Service Provider) in EMD system to flexibly deal with the change of IT and efficient implementation and integration of information system as well as to significantly reduce cost through wire/wireless high speed Internet network that is politically promoted in Korea on the basis of EMD. The system analysis and design was executed by HIPO (Hierarchy Plus Input Process Output) analysis that was the conceptual design technology for EMD information system modeling based on ASP and DFD (Data Flow Diagram). This study proposed DB table configuration and data schema to implement the application of web browser interface in EMD system through ERD(ER-Diagram) of EMD ASP system. Finally, this study described how to implement and utilize EMD information system. This study aims to facilitate the qualitative development of emergency medical service in the future as suggesting the concrete models for the implementation of high value-added prehospital emergency medical information system as applying ASP concept to EMD system of prehospital emergency medical service area.

• Journal of the Korea Convergence Society
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• v.10 no.2
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• pp.7-11
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• 2019

Due to diversification and popularization of devices that use rapid transmission, there are many security issues related to radio waves. As the disturbance and interference of the radio wave can cause a direct inconvenience to a life, it is a very important issue. In this paper, as a means to prevent radio disturbance and interference, the projected image of the reference grid and the deformed grid is obtained by measuring the projected $moir{\acute{e}}$ using the white light source, projecting grid and the light source, and a $moir{\acute{e}}$ pattern is generated with an image processing algorithm by applying a phase diagram algorithm, and generated $moir{\acute{e}}$ pattern phase diagram creates a three-dimensional shape. By making an encrypted token using this measured face shape, the transmission of the information through token ring is determined in order to transmit the horizontal transmission having the dynamic security characteristics which includes authentication strength and caller information, etc. And by confirming the uniqueness of the token and by sending and receiving the horizontal transmission using java serialization and deserialization function, a problem solving method is suggested.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.28 no.6
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• pp.1355-1369
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• 2018

As smart bands make life more convenient and provide a positive lifestyle, many people are now using them. Since smart bands deal with private information, security design and implementation for smart band system become necessary. To make a trustworthy smart band, we must derive the security requirements of the system first, and then design the system satisfying the security requirements. In this paper, we apply threat modeling techniques such as Data Flow Diagram, STRIDE, and Attack Tree to the smart band system to identify threats and derive security requirements accordingly. Through threat modeling, we found the vulnerabilities of the smart band system and successfully exploited smart bands with them. To defend against these threats, we propose security measures and verify that they are secure by using Scyther which is a tool for automatic verification of security protocol.

• Journal of architectural history
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• v.14 no.2 s.42
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• pp.7-20
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• 2005

Ceremony is important to Buddhism as a part of the religious practice. Buddhist ceremony is a kind of discipline and it rules the Chan monastery life. This discipline, called $\ulcorner$Qinggui(淸規)$\lrcorner$ also forms a part of the practice for enlightenment in the Chan monastery(禪宗). Qinggui is derived from $\ulcorner$Baizhang's monastic code(百丈淸規)$\lrcorner$ which no longer exists. $\ulcorner$Chanyuan qinggui(禪院淸規)$\lrcorner$ is considered the oldest surviving Chinese monastic discipline. Its success is partly due to the emphasis in the Chan monastery on the succession of monks to abbot hood. Qinggui has been called the only discipline in Buddhist monastic life in religion. Whether it is also the discipline of the architectural space of the Chan temples is the focus of this thesis. The examination of this assumption may expand the meaning of Qinggui as embodying not only the religious form of discipline but also a fundamental part of the architectural archive. The majority of the buildings in the Chan monastery in Qinggui are related to $\ulcorner$Five Mountains Ten Checks figures$\lrcorner$. Most of all, it can be clarified that the elements of Qinggui are expressed through the analysis of the activities in each building. This proves that Qinggui has become a stipulation not only for the regulation of the monastery life but also the architectural code of the Chan temples. In conclusion, this study shows how the meaning of ceremony and monastery life in $\ulcorner$Chanyuan qinggui$\lrcorner$ can be expanded to include the design program of temples. The research proves that there is a basic code in the Chan temples for designing the structure of the monastery space. Similarly, $\ulcorner$Five Mountains Ten Checks Figures$\lrcorner$ was a diagram for examination and analysis as well as a tool for creating drawings of the temples in the Song era.

• Journal of Korean Society of Steel Construction
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• v.10 no.1 s.34
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• pp.37-45
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• 1998

The relational database system on fatigue strength was constructed, and the properties of fatigue life distribution were examined to analyze reliability and safety of metallic materials. Data manipulations were efficiently performed in relational fatigue strength database system using dependency diagram. Regardless of the distribution of fatigue strength, the proposed method, the Robust method and the complementary error function method using probability distribution, successfully estimated parameters of the 3-parameter Weibull distribution. The proposed criterion for estimating non-failure probability showed good results regardless of censoring time. The fatigue life distribution function described as a function of parameters of the Weibull distribution and applied stress ratio produced P-S-N characteristics reasonably.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 1999.06a
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• pp.215-219
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• 1999

One of the innovative physical methods that provide insight into the basic processes which determine friction and wear behavior of coated machine tools is acoustic emission (AE). In this study, an investigation of the relation between AE and friction signal produced during repeated sliding test is presented. The material of test specimens is CrN coated 0.2% plain carbon steel with 1 Um thickness. The obtained results demonstrate that AE signal is very related with friction, and AE signal is more sensitive than friction when CrN coated film come off the substrate.

• Journal of the Korean Society for Precision Engineering
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• v.21 no.2
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• pp.130-137
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• 2004

A dynamic model of railway reducer is developed by the lumped parameter method. The model accounts for shafts, bearings flexibilities, gyroscopic effects and the force couplings among the transverse and torsion motions due to gearing. Vibration/noise analysis as well as strength of gear teeth, and bearing life are considered. Excitation forces of railway reduction are considered as the mass unbalance of the rotors, misalignment and a function of gear transmission error which comes from the modified tooth surface. A campbell diagram, in which the excitation sources caused by the mass unbalance of the rotors, misalignment and the transmitted errors of the gearing are considered, shows that, at the operating speed, there are not the critical speed. The program which can be used to analyze and predict vibration/noise characteristics by mass unbalance, misalignment and gear transmission error of railway reduction is developed with this system model.