• Proceedings of the Korean Information Science Society Conference
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• 2001.04b
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• pp.385-387
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• 2001

연속적인 절차를 필요로 하는 영역에서 사용자는 단계마다 검색과 정보 획득과정을 반복적으로 수행해야만 한다. 현재 인터넷으로 수행 가능성 영역의 절차에 대해서 검색과 확인 과정을 거치지 않고 시스템과 대화를 통해서 원하는 절차를 한번에 생성해주는 시스템을 개발하기 위해서는 이러한 개념을 수행해 줄 수 있는 지식 베이스 구축이 필요하다. 본 연구에서는 적용하려는 절차의 특성에 다라 대화 모델에서 의도 파악을 위한 Plan-based 기술을 적용할 수 있는 Goal Level과 사용자의 제약 조건을 파악하기 위해 Frame-based 기술을 적용할 수 있는 Constraint Level의 2단계 구조를 갖는 지식 베이스 구조를 제안한다.

• Journal of Broadcast Engineering
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• v.12 no.3
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• pp.289-292
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• 2007

A background initialization algorithm based on the spatiotemporal similarity measure in a motion tracking system is proposed. From the accumulated difference between the base frame and the other frames in a subinterval, the regions affected by moving objects are located. The median is applied over the subsequence in the subinterval in which co-located regions share the similarity. The outputs from each subinterval are filtered by second stage median filter. The proposed method showed good results even in the busy and crowded sequences where the real background does not exit.

• Honam Mathematical Journal
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• v.44 no.4
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• pp.594-617
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• 2022

In this study, firstly Smarandache ruled surfaces whose base curves are Smarandache curves derived from Frenet vectors of the curve, and whose direction vectors are unit vectors plotting Smarandache curves, are created. Then, the Gaussian and mean curvatures of the obtained ruled surfaces are calculated separately, and the conditions to be developable or minimal for the surfaces are given. Finally, the examples are given for each surface and the graphs of these surfaces are drawn.

• Journal of the Korea Concrete Institute
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• v.17 no.3 s.87
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• pp.419-426
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• 2005

This study is to propose a modified equivalent frame model for flat plate slabs under lateral loads. ACI 318 (2002) allows equivalent frame methods to conduct two-way slab system analysis subjected to gravity loads as well as lateral loads. Since the equivalent frame method in the ACI 318 (2002) has been developed base on the behavior of two-way system for gravity loads, and nay not predict the behavior of flat plate slabs under lateral loads with good precision. This study develops a modified equivalent frame model which can give more precise answer for flat plate slabs under lateral loads. This model reflects the actual force transfer mechanism among the components of flat plate slab system, which are slabs, columns and torsional members, more accurately under lateral loads than existing equivalent frame models. The accuracy of this model is verified by comparing the analysis results using the proposed model with the results of finite element analysis. The analysis results of other existing models are included in the comparison. For this purpose, 2 story building having 3 spans in both directions is considered. Analytical results show that the modified equivalent frame model produces comparable drift and slab internal moments with those obtained from finite element analysis.

• Journal of the Earthquake Engineering Society of Korea
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• v.5 no.5
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• pp.73-83
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• 2001

The mass and stiffness of upper wall-lower frame system(mixed building structures) change sharply at transfer floor due to different structural system in upper and lower part. These mixed building structures generally show the stiffness, weight or geometric vertical irregularities. The purpose of this study is to investigate the response characteristics of these structures by push-over analysis and nonlinear time history analysis. For four types of analysed models, only the variation of upper wall stories was considered. The conclusions of this study are following; (1) In the push-over analysis, yielding hinges in beams and columns of lower frame occurred at the base shear of similar magnitude in all models. But as the number of stories of upper wall increases, yielding hinges at ends of coupling beams were observed in the small magnitude of base shear. (2) In the nonlinear time history analysis, yielding of lower frame occurred at beams with as small ground acceleration as 55gal, and in upper walls yielding was concentrated on coupling beams and shear walls near the transfer floor. (3) As the number of stories of upper walls decreases, the story stiffness of the lower frames decreased relatively and the occurrence of soft stories in the lower frame was observed.

• Conservation Science in Museum
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• v.7
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• pp.53-62
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• 2006

The wooden armor frame and various lacquerware artifacts excavated from the low swamp remains in Imdang, Gyeongsan have very weak material and lacquer coating; in case they are exposed in the air, they are likely to be shrunken and deformed immediately. The wooden armor frame has large size and it might be dissolved during freeze-drying. The lacquer coating of lacquerware blocks the penetration of chemicals and it is very likely to swell or peel off during the treatment. Therefore, to prevent the dissolution during vacuum freeze-drying, the wooden armor frame was replaced with t-butanol and impregnated in t-butanol solution with PEG#3, 350 43%, and lacquerware was impregnated in PEG#3, 350 40% solution at room temperature and freeze-dried. According to the analysis of the lacquer fragment from the lacquerware, the lid and the mounted cup was pasted with the mixture of lacquer and black pigment (soot) on the base layer after the first coating and pasted two or three times more with natural lacquer; the red lacquered wooden cup was pasted with the mixture of lacquer and black pigment on the base layer and pasted once on the middle layer. The top lacquer (red) was pasted with the mixture of iron oxide(Fe₂O₃).

• Geomechanics and Engineering
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• v.4 no.4
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• pp.251-262
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• 2012

Triaxial tests are essential to estimate the shear strength properties of the soil or rock. Normally triaxial tests are carried out on samples of 38 mm diameter and 76 mm height. Granular materials, predominantly used in base/sub-base construction of pavements or in railways have size range of 60-75 mm. Determination of shear strength parameters of those materials can be made possible only through triaxial tests on large diameter samples. This paper describes a large diameter cyclic triaxial testing facility set up in the Geotechnical Engineering lab of Indian Institute of Science. This setup consists of 100 kN capacity dynamic loading frame, which facilitates testing of samples of up to 300 mm diameter and 600 mm height. The loading ram can be actuated up to a maximum frequency of 10 Hz, with maximum amplitude of 100 mm. The setup is capable of carrying out static as well as dynamic triaxial tests under isotropic, anisotropic conditions with a maximum confining pressure of 1 MPa. Working with this setup is a difficult task because of the size of the sample. In this paper, a detailed discussion on the various problems encountered during the initial testing using the equipment, the ideas and solutions adopted to solve them are presented. Pilot experiments on granular sub-base material of 53 mm down size are also presented.

• The Journal of Korean Society of Virology
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• v.30 no.1
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• pp.1-10
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• 2000

The nonstructural protein NSP4, encoded by gene 10 of rotavirus, has been shown to playa role in viral assembly and known to be an enterotoxin, causing diarrhea in mouse pups. NSP4 gene was cloned from CBNU-2 (virulent bovine rotavirus/diarrheic fecal sample) and CBNU-1 (cell-culture adapted bovine rotavirus/isolated from CBNU-2 and 75 times passaged on MA104 cells), respectively, by reverse transcriptase-polymerase chain reaction (RT-PCR) and sequenced and compared. The sequence data indicated that the NSP4 genes of bovine rotavirus (BRV) were 751 bases in length and encoded one open reading frame of 175 amino acids beginning at base 42 and terminating at base 569. Differences in nucleotide sequence between CBNU-2 and CBNU-1 were observed at 6 positions (base 274, 296, 391, 394, 396 and 579). NSP4 gene of BRV exhibited a high degree of nucleotide (90% and 94%) and amino acid sequence (91% and 97%) homology with those of SA11 and UK but a low degree of nucleotide (77% and 79%) and amino acids sequence (81% and 85%) homology with those of Wa and OSU.

• Earthquakes and Structures
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• v.23 no.1
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• pp.87-100
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• 2022

Limiting the displacement of seismic isolators causes a pounding phenomenon under severe earthquakes. Therefore, the ASCE 7-16 has provided minimum criteria for the design of the isolated building. In this research the seismic response of isolated buildings by Triple Friction Pendulum Isolator (TFPI) under the impact, expected, and unexpected mass eccentricity was evaluated. Also, the effect of different design parameters on the seismic behavior of structural and nonstructural elements was found. For this, a special steel moment frame structure with a surrounding moat wall was designed according to the criteria, by considering different response modification coefficients (RI), and 20% mass eccentricity in one direction. Then, different values of these parameters and the damping of the base isolation were evaluated. The results show that the structural elements have acceptable behavior after impact, but the nonstructural components are placed in a moderate damage range after impact and the used improved methods could not ameliorate the level of damage. The reduction in the RI and the enhancement of the isolator's damping are beneficial up to a certain point for improving the seismic response after impact. The moat wall reduces torque and maximum absolute acceleration (MAA) due to unexpected enhancement of mass eccentricity. However, drifts of some stories increase. Also, the difference between the response of story drift by expected and unexpected mass eccentricity is less. This indicates that the minimum requirement displacement according to ASCE 7-16 criteria lead to acceptable results under the unexpected enhancement of mass eccentricity.

• Earthquakes and Structures
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• v.24 no.1
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• pp.21-36
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• 2023

Structural vibrations generated by earthquakes and wind loads can be controlled by varying the structural parameters such as mass, stiffness, damping ratio, and geometry and providing a certain amount of passive or active reaction forces. A Double-Tuned Mass Dampers (DTMDs) system, which is simple and more effective than the conventional single tuned mass damper (TMD) system for vibration mitigation is presented. Two TMDs tuned to the first two natural frequencies were used to control vibrations. Experimental investigations were carried out on a three degrees-of-freedom frame model to investigate the effectiveness of DTMDs systems in controlling displacements, accelerations, and base shear. Numerical models were developed and validated against the experimental results. The validation showed a good match between the experimental and numerical results. The validated model was employed to investigate the behavior of a five degrees-of-freedom shear building structure, wherein mass dampers with different mass ratios were considered. The effectiveness of the DTMDs system was investigated for harmonic, seismic, and white noise base excitations. The proposed system was capable of significantly reducing the story displacements, accelerations, and base shears at the first and second natural frequencies, as compared to conventional single TMD.