• Proceedings of the KSR Conference
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• 2008.06a
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• pp.194-198
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• 2008

The necessities of development of foundation having minimized occupying area and construction time are required for overpass in the downtown area by which bimodal tram will pass a crossway. We are studying a single column drilled pier foundation which is continuous from pier to pile foundation. Due to the increased resisting moment by reinforced steel which is ranged from the upper part of pile to lower part of column above ground, it can be possible to make a smaller pile-section and lessen the bar reinforcing. And for the excavation work is possible with smaller equipment, this foundation has a improved constructability and economical efficiency. This foundation needs smaller amount of concrete and has a small self-weight. It has an effect on improving resistance against earthquake due to improved ductility in addition to improved rigidity by interaction between concrete and steel.

• Journal of architectural history
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• v.17 no.4
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• pp.65-82
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• 2008

The wooden pagoda sites which have been confirmed in Baekjae's former territory so far have flattened surface of the earth or foundation pert made by digging up the earth. In particular, the latter is found more often in the pagoda sites of Baekjae, which is essential and absolutely necessary because of the characteristics of pagoda structure. The wooden pagoda sites with foundation part made by digging up the earth under the stylobate are found at Yongjeongli ruined temple site of Woongjin area, and at Neung-sa temple site, Wangheung-sa temple site, Geumgang-sa temple site, and Mireuk-sa temple site of Sabi period. They are also observed at Hwanglyong-sa nine-storied wooden pagoda of Shilla and at Biin five-storied stone pagoda of early Goryeo. They are important data improving that the construction technologies of Baekjae continued to be applied to build stone or wooden pagodas, transcending time and space. Recently, the site assumed as a wood pagoda site of Hanseong area was examined in Gyeongdang sect ion of Pungnap mud fortification. If this is proved to be a real wooden pagoda site, this digging-up construction technology of foundation part ann be concluded to be a traditional engineering technology of Baekjae which was frequently used from Hanseong period to Sabi period. On the other hand, this digging-up construction technology of foundation part has been found only at pagoda sites and main building sites of temple ruins, and it helps examine their symbolism.

• Proceedings of the Korean Geotechical Society Conference
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• 2009.09a
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• pp.430-440
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• 2009

Top-Base Foundation(TBF) was developed in Japan as a factory made concrete product. It is actively used in 6,000 sites by the end of 1980s in Japan and applied for a domestic patent in 1985. It is a shallow foundation whose effectiveness is proven by many relevant researchers and engineers. TBF was introduced to Korea in 1991 and has been applied mainly to architectural structures to date. Currently, the effectiveness in bearing capacity and settlement of TBF is being underestimated for civil engineering structures. Characteristics of Top-Base Foundation studied in Japan and Korea is known as follows: (1) as concrete part and crushed stone behave together, they perform the function of rigid mat; (2) the conical part and pile part of TBF disperses load by interaction with the crushed stone; (3) by preventing lateral strain and differential settlement on lower ground, it improves bearing capacity and constrains settlement at the same time. In Korea, it is used mostly in clayey soft grounds. The formula of bearing capacity and settlement of TBF suggested in Japan give the values of the underestimated. bearing capacity while its settlement is overestimated in comparison with the values measured from the field loading test. Therefore, in this study, the stress delivery mechanism of Top-Base Foundation developed in Japan and Floating Top Base developed in Korea is investigated through numerical analysis and laboratory model test.

• Proceedings of the Korean Geotechical Society Conference
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• 1994.09a
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• pp.182-190
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• 1994

Mattress foundations using geogrids are often used on soil foundations to increase the supporting capability of a mattress-soil foundation system, in which the mattress foundation trasmits a point load applied above to a wider area of the soil foundation underneath. To examine this load dispersion capability of the mattress foundation, model experiments were carried out on lab-floor. Expecially, the effect of the thickness of the mattress and the subgrade modulus of the soil foundation on load dispersion are considered. The load distribution and the tensile force generated on geogrid of the upper part of the mattress are examined in the paper.

• Journal of the Korean Geotechnical Society
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• v.24 no.10
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• pp.121-129
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• 2008

Numerical analysis for the in-situ top base foundation (In-situ TBF) was carried out in order to investigate the effect of bearing capacity and the load delivering mechanisms in granular soil. The input data for the numerical model was prepared from the result obtained from the plate load test and full size in-situ TBF field tests. According to the result of numerical analysis, the behavior of in-situ TBF showed that bearing capacity of the foundation increased by $50{\sim}100%$ and settlement was reduced up to $1/2{\sim}1/3$ comparing to other types foundation. The effect of cone-shaped part of the in-situ TBF was as important as pile part for the improvement of foundation stability. The variation of the length of pile part indicated that the present length was proved satisfactory in terms of effectiveness.

• Proceedings of the Korea Concrete Institute Conference
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• 2006.05a
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• pp.630-633
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• 2006

In this study, we concerned the steel cap and head part arrangement of PHC pile structure to complement existing construction process which have the defects such as highly hazardous circumstance for safety concerns and retard a term of works. The steel cap developed for supplement the stiffness between extend foundation and contact section of PHC pile that is based on structural theory. The experiments have been performed to evaluate the characteristics of behavior between head part of PHC pile using steel cap and extend foundation.

• Journal of the Korean Society for Precision Engineering
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• v.21 no.8
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• pp.188-195
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• 2004

In this paper we analyzed the mechanical behavior with respect to the thickness variation of elastic foundation(fatty tissue) in end-to-end anastomosis. This study considered the preliminary deformed shape induced by suturing in the anastomosis of coronary artery and PTFE with different diameters using simplified suturing model and the fatty tissue surrounding heart and coronary artery for more accurate result using finite element method. Area compliance(CA) was used to analyze the final deformed shape of the anastomotic part with respect to the thickness variation of fatty tissue under mean blood pressure, 100mmHg(13.3㎪). And Equivalent and circumferential stresses in the anastomosis were also analyzed with respect to the change of initial diameter ratio( $R_1$) and fatty tissue thickness( $T_{F}$). The results obtained were as follows : 1 When the elastic foundation, assumed to be incompressive material, surrounded the grafts in anastomosis, the compliance mismatch of artery and PTFE was reduced by 47 -72%. 2. As the initial diameter ratio( $R_1$) became larger, the higher difference of compliance was induced in spite of elastic foundation surrounding grafts. 3. The maximum nondimensional circumferential stress is twice or three times as high as the maximum nondimensional equivalent stress in the anastomotic part.t.

• IEMEK Journal of Embedded Systems and Applications
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• v.16 no.6
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• pp.313-321
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• 2021

The global market for medical devices is huge, and it will continue showing remarkable growth in the future. However, due to the entry barrier to develop medical devices, many domestic companies have technical problems in entering the medical device industry. In this paper, we introduce an open platform that can help with research and development for companies in the healthcare industry. This open platform consists of a hardware part and a software part. A hardware part is combined into CPU, base and other modules that are easy to replace and assemble. A software part is based on application software for development developed by Bionet. We test the performance of the open medical device platform using a biosignal processing algorithm.

• Journal of the Korean Society for Precision Engineering
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• v.18 no.11
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• pp.74-79
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• 2001

In this two-part paper, a virtual machine tool (VMT) is presented. In part 1, the analytical foundation of a virtual machining system, envisioned as the foundation for a comprehensive simulation environment capable of predicting the outcome of cutting processes, is developed. The VMT system purposes to experience the pseudo-real machining before real cutting with a CNC machine tool, to provide the proper cutting conditions for process planners, and to compensate or control the machining process in terms of the productivity and attributes of products. The attributes can be characterized with the machined surface error, dimensional accuracy, roughness, integrity and so forth. The main components of the VMT are cutting process, application, thermal behavior and feed drive modules. In part 1, the cutting process module is presented. The proposed models were verified experimentally and gave significantly better prediction results than any other method. The thermal behavior and feed drive modules are developed in part 2 paper. The developed models are integrated as a comprehensive software environment in part 2 paper.

• Geomechanics and Engineering
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• v.35 no.2
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• pp.195-208
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• 2023

The nodular diaphragm wall (NDW) is a novel type of foundation with favorable engineering characteristics, which has already been utilized in high-rise buildings and high-speed railways. Compared to traditional diaphragm walls, the NDW offers significantly improved vertical bearing capacity due to the presence of nodular parts while reducing construction time and excavation work. Despite its potential, research on the vertical bearing characteristics of NDW requires further study, and the investigation and visualization of its displacement pattern and failure mode are scant. Meanwhile, the measurement of the force component acting on the nodular parts remains challenging. In this paper, the vertical bearing characteristics of NDW are studied in detail through the indoor model test, and the displacement and failure mode of the foundation is analyzed using particle image velocimetry (PIV) technology. The principles and methods for monitoring the force acting on the nodular parts are described in detail. The research results show that the nodular part plays an essential role in the bearing capacity of the NDW, and its maximum load-bearing ratio can reach 30.92%. The existence of the bottom nodular part contributes more to the bearing capacity of the foundation compared to the middle nodular part, and the use of both middle and bottom nodular parts increases the bearing capacity of the foundation by about 9~12% compared to a single nodular part of the NDW. The increase in the number of nodular parts cannot produce a simple superposition effect on the resistance born by the nodular parts since the nodular parts have an insignificant influence on the exertion and distribution of the skin friction of NDW. The existence of the nodular part changes the displacement field of the soil around NDW and increases the displacement influence range of the foundation to a certain extent. For NDWs with three different nodal arrangements, the failure modes of the foundations appear to be local shear failures. Overall, this study provides valuable insights into the performance and behavior of NDWs, which will aid in their effective utilization and further research in the field.