• Proceedings of the Korean Operations and Management Science Society Conference
• /
• 2003.11a
• /
• pp.329-333
• /
• 2003

This study presents supplier buyer models representing the interactions between supplier and buyer under a long-term replenishment contract in a supply chain system. We established the models according to the economic power of each party. Analysis based on Stackelberg game theoretic approach is tried for each model. We develop methods for each agent to follow to complete a contract for the best interest of each participant.

• Proceedings of the Earthquake Engineering Society of Korea Conference
• /
• 1999.10a
• /
• pp.155-161
• /
• 1999

Many direct integration methods have been developed for dynamic analysis of structures, In order to compare each other methods and give guideline for selecting a time increment the amplification matrix is constructed according to algorithm of each method and stability and accuracy analysis is done. Four story shear building under external excitations is analyzed by each method and the RMS errors of displacements of top floor and compared with each other.

• Proceedings of the Korea Concrete Institute Conference
• /
• 2000.10b
• /
• pp.1001-1006
• /
• 2000

These should be constructed partially, because many prestressed concrete box girder bridges in situ have large cross section and long span. Therefore, accurate prediction of differences, both elapse time of each construction stage and exposure of atmosphere at each position of cross section, is very important. Though it is importance, engineers are apt to overlook it. This study predicted cracks due to shrinkage and stress concentration phenomenon by each construction stage and then, ascertained reduction of tensile stresses after applying retrofit scheme.

• Proceedings of the Computational Structural Engineering Institute Conference
• /
• 2000.10a
• /
• pp.323-330
• /
• 2000

Three historical earthquake catalogues were compared with each other in the view of frequency of events per century, cumulative magnitude distribution, and annual earthquake occurrence rate in each unit grid of 0.1°by 0.1°. And, a method to determine earthquake epicenters and magnitudes was proposed given the historical earthquake data. With this method, the epicenters and magnitudes of future earthquakes in Korean penninsula for 1,000 years were generated with each earthquake catalogue. Earthquake PGAs with 10% exceedance probability in Seoul were calculated for each catalogue and compared.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
• /
• 2002.10a
• /
• pp.135-140
• /
• 2002

Studies on the optimization of machining process can be divided into two different approaches: off-line feedrate scheduling and adaptive control. Each approach possesses its respective strong and weak points compared to each other. That is, each system can be complementary to the other. In this regard, a combined system, which is a feedrate control system for cutting force optimization, was proposed in this paper to make the best of each approach. Experimental results show that the proposed system could overcome the weak points of two systems.

• Economic and Environmental Geology
• /
• v.8 no.3
• /
• pp.125-133
• /
• 1975

The entire South Korea was divided into several main river basins and drilling data through the South Korea were grouped in accordance with the basins. Thickness of each alluvial formation in each basin was averaged to produce the thickness of the whole alluvium. From studying the alluvial stratigraphy of each basin the condition of the alluvial sedimentation was studied and compared between different basins. Thus the characteristics of the alluvial sedimentation in each basin was clarified.

• PNF and Movement
• /
• v.6 no.2
• /
• pp.19-30
• /
• 2008

Purpose : This study was performed for find out temporal spatial parameter of the gait according to age. Method : Four groups of healthy people were allocated randomly in this study : group I(little child, 15), group II(child, 18) and group III(young people, 17), group(elder people, 16). This study was performed from 01 December to 31 December in 2007. Results : The results were as follows : 1. The swing phase was the longest group II, group IV was the shortest. Each groups, there was significant difference in swing phase(p<.05). 2. The stance phase was the longest group IV, group II was the shortest. Each groups, there was significant difference in stance phase(p<.05). 3. The single support time was the longest group II, group IV was the shortest. Each groups, there was significant difference in single support time(p<.05). 4. The double support time was the longest group IV, group II was the shortest. Each groups, there was significant difference in double support time(p<.05). 5. The gait velocity was the fastest group II, group I was the slowest. Each groups, there was significant difference in gait velocity(p<.05). 6. The toe in/out was very increased group IV, group I was very decreased. Each groups, there was significant difference in toe in/out(p<.05). 7. The cadence was the highest group I, group IV was the lowest. Each groups, there was significant difference in cadence(p<.05). 8. The step length was the longest group III, group I was the shortest. Each groups, there was significant difference in step length(p<.05). 9. The step length asymmetry ratio was the highest group IV, group III was the lowest. Each groups, there was no significant difference in step length asymmetry ratio(p>.05). 10. The single support time asymmetry ratio was the highest group I, group IV was the lowest. Each groups, there was no significant difference in single support time asymmetry ratio (p>.05). 11. The FAP was the highest group III, group I was the lowest. Each groups, there was significant difference in FAP(p<.05).

• Journal of the korean academy of Pediatric Dentistry
• /
• v.24 no.1
• /
• pp.148-172
• /
• 1997

Sixty human premolar teeth were used for this in vitro study. After each tooth was sectioned mesiodistally, one half was used for the experimental group and the other half for the control. Three groups were made for each fluoride applying method and twenthy teeth were assigned to each group. Ten teeth were used for evaluating total fluoride amount and the other ten were used for firmly-bound fluoride. Fluorshield was used for fluoride-releasing sealant and 1.23% APF, 0.05% NaF were used for topical application fluorides. Each tooth was cleaned with a tooth brush using nonfluoride containing pumice before the experiment. In the sealant group, fluoroshield was applied to the enamel surface without etching procedure and stored in $37^{\circ}C$ saline for 30 days. After 30 days, sealant was removed with explorer without scratching the enamel surface and washed with distilled water and dried. In the APF group, each tooth was immersed in 1.23% APF for 30 min then washed and dried in the same manner. In the NaF group, each tooth was immersed in 0.05% NaF for 24 hours then washed and dried as described above. After each fluoride regimen was applied, ten teeth were randomly selected from each group and immersed in 1M KOH solution for 24 hours to remove loosely-bound fluoride possibly deposited by the three different fluorides applied. In each group, total fluoride amount deposited and the amount of enamel removed by acid biopsy were calculated. After loosely-bound fluoride was removed, firmly-bound fluoride deposited and the amount of enamel removed by acid biopsy were also calculated. Total fluoride amount deposition was significantly increased in the APF and NaF groups, but not in the sealant group. Amount of enamel removed by acid-biopsy was also significantly diminished in the APF and NaF groups, but not in the sealant groups. After loosely-bound fluoride was removed from each groups, no statistical difference was found in the amount of firmly-bound fluoride in any groups. Also no effect of firmly-bound fluoride on enamel dissolution was shown in any groups after loosely-bound fluoride was removed from each group. In conclusion, topical application method of APF or NaF is more effective than fluoride-releasing sealant application to make $CaF_2$ coating on enamel surface and $CaF_2$ coating is the main source for anticariogenic effect of fluoride. However, longterm anticariogenic effect of fluoride-releasing sealant should be further evaluated.

• Journal of Acupuncture Research
• /
• v.27 no.6
• /
• pp.77-84
• /
• 2010

Objectives : This study was to compare the incipient grade and improvement rate between each opposite gender and part on peripheral facial nerve paralysis. Methods : We investigated 64 cases of patient with peripheral facial nerve paralysis and divided into four groups with each gender and affected part and compared their incipient grade and rate of improvement. All groups were evaluated by Yanagihara's unweighted grading system before treatment and in everyday and after treatment. Results & Conclusion : 1. There's a difference of incipient grade between each opposite affected lesion in male. But there was not significant statistics. 2. There's no difference of incipient grade between each opposite affected lesion in female. 3. There's a difference of incipient grade between each opposite gender, affected their right side. But there was not significant statistics. Left side affecting palsy is more severe than right in male, and reversed results in female. But there were not significant statistics. There's no differences between each affected lesion in female. 4. There's no differences of improvement rate between each affected lesion in female. 5. The group, affected right side had better rate of improvement than another in male. But it's not significant statistics. 6. Male group had better rate of improvement than female in both gender, affected its left lesion. But it's not significant statistics.

• Journal of the Korean Society of Systems Engineering
• /
• v.11 no.2
• /
• pp.1-11
• /
• 2015

During the industrial plant system life cycle, required technologies are developed and assessed to analyze their performance, risks and costs. The assessment is called technology readiness assessment (TRA) and the measure of readiness is called technology readiness level (TRL). The TRL consists of 9 levels and through the TRL assessment, the technology to be developed and its components are assigned to their appropriate TRL. TRL assessment should be performed in each life cycle stages to monitor the technology readiness and analyze the potential risks and costs. However, even though the concept of TRL has been largely adopted by numerous organizations and industry, direct and clear assignment of target TRL for each life cycle stage has been overlooked. Direct mapping/assignment of target TRL for each life cycle has benefits as follow: (1) the technical risks condition of each life cycle stage can be better understood, (2) cost incurred if the technology development is failed can be analyzed in each life cycle stage, and (3) more effective decision making because the technology readiness achievement for each life cycle stages is agreed beforehand. In this paper, we propose a steel-making plant system life cycle and TRL assignment to each of the system life cycle stage. By directly assigning target TRL for each life cycle stages, we look forward to a more coordinated (in terms of exit criteria) and highly effective (in terms of technical risks identification and eventually prevent project failure) technology development and assessment processes.