• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.11 no.2
• /
• pp.584-589
• /
• 2010

In this paper we suggest multimedia synchronization model that is based on the Petri-net and services desirable quality of service requirement. Proposed model applies variable buffer which can be allowed, and then it presents high quality of service and real time characteristics. In this paper we expend Petri-net and propose new multimedia synchronization specification model in PBMSM and apply two analysis method of Petri-net to prove our model suggested. We compared with other models and showed high QoS.

• Journal of the Korean Society of Systems Engineering
• /
• v.4 no.2
• /
• pp.55-61
• /
• 2008

In this paper, there is the case study which assesses the systems engineering capability maturity of the safety organization that performs the Railway Safety project using systems engineering method. To In ore effective and efficient a research and development to railway safety domain, a new research and development method can be progressively needed such as systems engineering. To assess quantitatively research of systems engineering efforts in the railway safety project, SECM(EIA/IS 731) Standard is utilized in the paper. It is by questionnaire that the capability maturity assessment is executed wit h the safety organization and staffs who performs the systems engineering activities; requirement analysis and management, interface control management. product verification and validation, and so on. As a result, the systems engineering capability level of the safety organization rises from 0 level at the initial project to 2 level after two years and all staffs give an affirmative answer about the importance and effectiveness of the systems engineering approach.

• The Transactions of the Korea Information Processing Society
• /
• v.5 no.10
• /
• pp.2546-2555
• /
• 1998

Existing Systems need to be modified due to the change of environment, the emergence of new technology and the requirement of change. One of the features of system transformation is how functions of the old system is preserved in the transformed system after reverse-engineering. But, the techniques to evaluate and verigy the transformed system have proceeded more partially and fragmentarily. In this paper, we have proposed the functional coverage and developed the tool and techniques for verifying functional euivalence between a procedural software and a transformed object-oriented software. The tool and methods are efficiently used to verigy whehter the transformed program preserves the same functionality as the existing program.

• Journal of Positioning, Navigation, and Timing
• /
• v.9 no.3
• /
• pp.285-292
• /
• 2020

This paper introduces a new computational efficient Dilution of Precision (DOP)-based landmark exclusion method while ensuring the safety of the LiDAR-based navigation system that uses an innovation-based Nearest-Neighbor (NN) Data Association (DA) process. The NN DA process finds a correct landmark association hypothesis among all potential landmark permutations using Kalman filter innovation vectors. This makes the computational load increases exponentially as the number of landmarks increases. In this paper, we thus exclude landmarks by introducing DOP that quantifies the geometric distribution of landmarks as a way to minimize the loss of integrity performance that can occur by reducing landmarks. The number of landmarks to be excluded is set as the maximum number that can satisfy the integrity risk requirement. For the verification of the method, we developed a simulator that can analyze integrity risk according to the landmark number and its geometric distribution. Based on the simulation, we analyzed the relationship between DOP and integrity risk of the DA process by excluding each landmark. The results showed a tendency to minimize the loss of integrity performance when excluding landmarks with poor DOP. The developed method opens the possibility of assuring the safety risk of the Lidar-based navigation system in real-time applications by reducing a substantial amount of computational load.

• Journal of the Korean Data and Information Science Society
• /
• v.22 no.5
• /
• pp.857-866
• /
• 2011

The role of admissions officers is to evaluate the overall qualification of applicants, which consists of various qualitative and subjective metrics The core requirement of admissions officers is not only assessment of students' qualification based on the application but also verification of the data stem from the various sources. The issue for fairness on selection is the crucial agenda for the whole process of university entrance. The educational program aimed on the enhancement the expertise of admissions officers is required to guarantee the fair selection of whole evaluation process. In this paper we developed educational training program for admissions officers of J university. The 9 core dimensions of curriculum is presented to train admissions officers and the stepwise requirements of achieving each subject's goal are defined.

• Journal of the Korean Society for Precision Engineering
• /
• v.18 no.9
• /
• pp.110-121
• /
• 2001

During hot pipe bending using induction heating, the wall of bending outside is thinned by tensile stress. In design requirement, the reduction of wall thickness is not allowed to exceed 12.5%. So in this study, two methods of bending, one is loading of reverse moment and the other is loading of temperature gradient, have been investigated to design pipe bending process that satisfy design requirements. For this purpose, finite element analysis with a bending radius 2Do(outer diameter of pipe) has been performed to calculate proper reverse moment and temperature gradient to be applied. Induction heating process has been analyzed to estimate influence of heating process parameters on heating characteristic by finite difference method. Then pipe bending experiments have been performed for verification of finite element and finite difference analysis results. Experimental results are in good agreement with the results of simulations.

• Journal of Positioning, Navigation, and Timing
• /
• v.9 no.2
• /
• pp.71-77
• /
• 2020

KRS which is subsystem of Korea Augmentation Satellite System (KASS) performs a role of collecting and monitoring GPS signals. In order to generate the accurate correction message, the site which meets the requirements should be selected and verification to meet each requirement should be accompanied. When the sites are selected, the environmental considerations are EMI, clear horizon (CH) and multipath. Of these, EMI and CH can be checked for satisfaction by instrumentation, but multipath error is difficult to predict. Therefore, multipath error analysis for the installation position of actual antenna at each KRS site should be preceded, and multipath scenario should be generated for each location to analyze the effects of the resulting system performance. In this paper, based on satellite signals collected from each KRS sites, the method for analyzing multipath error in each KRS sites is described, and the multipath error is analyzed. Also to perform an analysis of the effects on system performance due to multipath error, multipath error modeling is performed for the generation of simulation scenarios.

• Proceedings of the KSR Conference
• /
• 2010.06a
• /
• pp.282-291
• /
• 2010

In line with current speed-up of railroad, a slab track has been increasingly adopted in a bid to secure the safety of track structure as well as to reduce the maintenance cost, and furthermore, the need for commercialization of domestically-developed swing-nose crossing turnout on slab track has been on the rise. For commercialization of swing-nose crossing turnout on slab which was developed in Korea, a technical and systematic performance evaluation system, considering local environment, shall be established and then the performance evaluation shall be accordingly implemented. This paper was intended to summarize the performance evaluation system, referring to the data available at home and abroad and the results of performance evaluation for domestically-developed swing-nose crossing turnout on slab track carried out to date based on that system. A performance evaluation system comprises the technical requirement appropriateness evaluation(component performance evaluation and design verification), laboratory test and on-site test. For domestically-developed swing-nose crossing turnout on slab track, appropriateness evaluation and laboratory test have been completed and the on-site test of those installed on the 2nd phase of Kyung-Bu HSR is underway now.

• Proceedings of the SAREK Conference
• /
• 2009.06a
• /
• pp.102-107
• /
• 2009

Window system is an essential component for lighting, ventilation and thermal environment in buildings. Moreover, as balcony extension in apartment houses become legalized, the performance requirements of window systems in balcony space are getting complicated. However, at this moment, five properties of the windows are used to represent the performance aspects of the system, including wind resistance, air tightness, water tightness, sound insulation, thermal resistance. And such single properties are not capable to express the performance of a space with the window systems in terms of performance concept. A performance analysis with wholistic approach is required to see the effect of the window system in built environment. Thus, performance-based approach should be established, which will be able to evaluate the goal/function and comfort of occupants/owners. As the first step to develop the performance indicator for the window systme for balcony space, this study conducts a survey to find the required performance aspects. A complete set of performance-based indicators will be developed with verification methods in the later stage of research.

• Journal of the Korean housing association
• /
• v.8 no.3
• /
• pp.81-90
• /
• 1997

Cheju province exposes a separated residential culture compared to the mainland area. since it has its own unique climate, natural features. Therefore, this study tried to grasp the residential behavior. was based on the questionnaire to Cheju province people, using the approach by statistic verification. This study also focused and aimed on suggesting the basic data about housing plan which is appropriate to the climate. natural features requirement from inhabitants through the comparison and analysis between the mainland area and Cheju province. The results of the study are as follows; Firstly. the diversified applicative study on ‘Ol-rae’. ‘Ma-dang’, ‘Yoo-young’ and so forth that is traditional outside garden of Cheju is imperative, because in urban area people think traffics, vicinity, etc. are more significant, and in rural area people think occupying large outside space is more significant. Secondly. in the study of the degree of satisfaction on the housing, most of the people's was ‘neutral’ and in rural area quite a lot of negative reaction exposed. This is owing to the uniform introduction on residential style of the mainland area. Thirdly, housing plan should be considered family members' housing needs and provincial characteristics, meanwhile most of the people answered positively about the residential value which is considered very significant lately, for instance, security of privacy. appropriate plan for child's room.