• Journal of the Korea Academia-Industrial cooperation Society
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• v.12 no.5
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• pp.2383-2389
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• 2011

Ubiquitous applications require hybrid continuous query processing which processes both on-line data stream and spatial data in the disk. In the hybrid continuous spatial query processing, disk access costs for the high-volume spatial data should be minimized. However, previous indexing methods cannot reduce the disk seek time, because it is difficult that the data are stored in contiguity with others. Also, existing methods for the space-filling curve considering data cluster have the problem which does not cluster available data for queries. Therefore, we propose the region storage structure for efficient data access in hybrid continues spatial query processing. This paper shows that there is an obvious improvement of query processing costs through the contiguous data storing method and the group processing for user queries based on the region storage structure.

• Journal of Korea Technology Innovation Society
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• v.14 no.spc
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• pp.1232-1255
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• 2011

This paper proposes a model for demand forecasting that will require less effort in the process of utilizing the new product diffusion model while also allowing for more objective and timely application. Drawing upon the theoretical foundation provided by the hype cycle model and the consumer adoption model, this proposed model makes it possible to estimate the maximum market potential based solely on bibliometrics and the scale of the early market, thereby presenting a method for supplying the major parameters required for the Bass model. Upon analyzing the forecasting ability of this model by applying it to the case of the hybrid car market, the model was confirmed to be capable of successfully forecasting results similar in scale to the market potential deduced through various other objective sources of information, thus underscoring the potentials of utilizing this model. Moreover, even the hype cycle or the life cycle can be estimated through direct linkage with bibliometrics and the Bass model. In cases where the hype cycles of other models have been observed, the forecasting ability of this model was demonstrated through simple case studies. Since this proposed model yields a maximum market potential that can also be applied directly to other growth curve models, the model presented in the following paper provides new directions in the endeavor to forecast technology diffusion and identify promising technologies through bibliometrics.

• Bulletin of the Korean Chemical Society
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• v.32 no.1
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• pp.277-280
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• 2011

We studied the relative stability and atomic structure of five $C_{20}^{2+}$ isomers obtained by two-electron ionization of a $C_{20}$ cage (the smallest fullerene). All the isomers are bond-stretch isomers, i.e., they differ in bond length. In particular, in one of the isomers with Ih symmetry, all the bond lengths are equal. Full geometry optimizations of the dipositive ion $C_{20}^{2+}$ were performed using the hybrid density functional (B3LYP/6-31G(d)) methods. All isomers were found to be true minima by frequency analysis at the level of B3LYP/6-31G(d) under the reinforced tight convergence criterion and a pruned (99,590) grid. The zero-point correction energy for the cage bond-stretch isomers was in the increasing order $D_{2h}<C_{2h}<C_2<T_h<I_h$ of $C_{20}^{2+}$. The energy difference among the isomers of cage dipositive ions was less than that among neutral cage isomers. Our results suggest that these isomers show bond-stretch isomerism and that they have an identical spin state and an identical potential energy curve. Although the predominant electronic configurations of the isomers are similar, the frontier orbital characteristics are different, implying that we could anticipate an entirely different set of characteristic chemical reactions for each type of HOMO and LUMO.

• Steel and Composite Structures
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• v.53 no.1
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• pp.103-114
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• 2024

This study proposes a new hybrid approach that utilizes post-earthquake survey data and numerical analysis results from an evolving finite element routing model to capture vulnerability processes. In order to achieve cost-effective evaluation and optimization, this study introduced an online data evolution data platform. The proposed method consists of four stages: 1) development of diagnostic sensitivity curve; 2) determination of probability distribution parameters of throughput threshold through optimization; 3) update of distribution parameters using smart evolution method; 4) derivation of updated diffusion parameters. Produce a blending curve. The analytical curves were initially obtained based on a finite element model used to represent a similar RC building with an estimated (previous) capacity height in the damaged area. The previous data are updated based on the estimated empirical failure probabilities from the post-earthquake survey data, and the mixed sensitivity curve is constructed using the update (subsequent) that best describes the empirical failure probabilities. The results show that the earthquake rupture estimate is close to the empirical rupture probability and corresponds very accurately to the real engineering online practical analysis. The objectives of this paper are to obtain adequate, safe and affordable housing and basic services, promote inclusive and sustainable urbanization and participation, implement sustainable and disaster-resilient buildings, sustainable human settlement planning and management. Therefore, with the continuous development of artificial intelligence and management strategy, this goal is expected to be achieved in the near future.

• Journal of the Korean Geotechnical Society
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• v.34 no.12
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• pp.133-143
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• 2018

Concrete filled steel tube (PCFT) piles, which compose PHC piles inside thin steel pipes, were developed to increase the flexural strength of the pile with respect to the horizontal load. In order to compare the flexural strength of PCFT pile with that of steel pipe pile, several flexural tests were performed on the PCFT and steel pipe piles with the same diameter and the P-M curves for both piles were constructed by the limit state design method. Four test piles were also installed and lateral pile load tests were performed to compare the lateral load capacities and lateral behaviors of the hybrid composite piles using PCFT piles and the existing piles such as HCP and steel pipe piles. The flexural test results showed that the flexural strength of PCFT piles was 18.7% higher than that of steel pipe piles with thickness of 12mm and the same diameter, and the mid-span deflection of piles was 50% lower than that of steel pipe piles at the same bending moment. From the P-M curves, it can be seen that the flexural strength of PCFT piles subjected to the vertical load is greater than that of steel pipe piles, but the flexural strength of PCFT piles subjected to the pullout load is lower than that of steel pipe piles. In addition, field pile load tests showed that the PCFT hybrid composite pile has 60.5% greater lateral load capacity than the HCP and 35.8% greater lateral load capacity than the steel pipe pile when the length of the upper pile in hybrid composite piles was the same.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2005.05a
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• pp.877-882
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• 2005

Dynamic stability of an axially accelerating beam stucture is investigated in this paper. The equations of motion of a fixed-free beam are derived using the hybrid deformation variable method and the assumed mode method. Unstable regions due to periodical acceleration are obtained by using the Floquet's theory. Stability diagrams are presented to illustrate the influence of the dimensionless acceleration, amplitude, and frequency. Also, buckling occurs when the acceleration exceeds a certain value. It is found that relatively targe unstable regions exist around the first bending natural frequency, twice the first bending natural frequency, and twice the second bending natural frequency. The validity of the stability diagram is confirmed by direct numerical integration of the equations of motion.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.18 no.8
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• pp.864-871
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• 2008

The tilting trains can run on curve track about 30% faster than conventional train without affecting passenger comfort. As the tilting trains offer the optimum means of providing faster and more comfortable rail service with minimum of environmental disturbance and capital investment, it is widely adopted for commercial operation all over the world. Over several years, the Korea Railroad Research Institute(KRRI) and Ministry of Construction and Transportation(MOCT) have been developing 200 km/h Korean tilting train, Hanvit200. Hanvit200 adopts the pendulum type tilting mechanism and hybrid car body structure, mainly CFRP combined with steel. In this paper the vibrational characteristics of Hanvit200 was investigated through Eigen vector analysis, modal test and main line running test.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2008.04a
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• pp.519-524
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• 2008

The tilting trains can run curve track about 30% faster than conventional train without affecting passenger comfort. As the tilting trains offer the optimum means of providing faster and more comfortable rail service with minimum of environmental disturbance and capital investment, it is widely adopted for commercial operation all over the world. Over several years, the Korea Railroad Research Institute(KRRI) and Ministry of Construction and Transportation(MOCT) have been developing 200 km/h Korean tilting train, Hanvit200. Hanvit200 adopt the pendulum type tilting mechanism and hybrid car body structure, mainly CFRP combined with steel. In this paper the vibrational characteristics of Hanvit200 was investigated through Eigen vector analysis, Modal Test and main line running test.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.18 no.2
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• pp.174-179
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• 2005

We have designed a novel single cell gap transflective display associated with dual orientation of the liquid crystal. Owing to hybrid alignment in reflective part, the effective cell retardation value becomes half of cell retardation value in transmissive part where the LCs are homogeneously aligned. This study shows the possibility to manufacture the transflective display with a single gamma curve for reflective and transmissive region. The new device shows a high image quality with relatively easy fabrication.

• 한국연소학회:학술대회논문집
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• 2002.11a
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• pp.25-31
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• 2002

For the better understanding of the stability of turbulent combustion, more researches on extinction and re-ignition are needed. Flame interactions in non-premixed flame have also not been greatly researched. We made a hybrid twin jet flame, the combinations of diffusion flame and partially-premixed diffusion flame, in a twin jet counterflow configuration. The extinction limits of a crossed twin jet counterflow have been extended in comparison with those of a one-dimensional counterflow because of flame interactions through heat transfer and joint ownership of various radicals. Besides, we have obtain ignition $Damk\"{o}hler$ number by experimental method without external ignition source using the extinction characteristic in a crossed twin jet counterflow flame. From results, we can identify the hysteresis between extinction and ignition $Damk\"{o}hler$ number in S-curve.