• The Bulletin of The Korean Astronomical Society
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• v.17
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• pp.14.2-14.2
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• 1992

• Transactions of the Korean Society of Mechanical Engineers
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• v.19 no.6
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• pp.1351-1362
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• 1995

A method to estimate the torsional critical speed for practical rotors has been developed in this study. First, the rotor with a uniform shaft segment is modeled for undamped torsional motion analysis, while satisfying all the boundary conditions. This eventually generates governing equations for the torsional critical speeds of the system. The set of governing equations has the form of a sparse and banded matrix. The elements of banded matrix can be arranged in partitions, which correspond to the specific boundary of the rotor. This permits an automatic generation of the system matrix using a computer. In order to calculate the determinant generated by the simultaneous equations, which leads to the torsional critical speed, a recurring numerical algorithm for a (3*4) sub-matrix has been used. This numerical algorithm practically examines successive (3*4) sub-matrix, one at a time, instead of treating a huge matrix. The output of the program provides the mode shapes with continuous curves. The method has been implemented to three rotors given as examples : a simple rotor, Prohl's rotor, and Macmillan rotor.

• Journal of Korea Foundry Society
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• v.9 no.1
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• pp.73-79
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• 1989

Microstructural characteristics of Al-3.63wt.%Pb hyper-monotectic alloy rapidly-solidified by melt spinning were examined. Possibility of forming a planar liquid -solid interface during rapid solidification of this alloy was also considered with a morphological stability theory, and a mechanism of forming banded structure observed at the bottom parts of melt-spinned specimens was considered as well. Application of the absolute stability criterion predicts the liquid-solid interface of the primary aluminium phase to be able to maintain a planar interface during the early stage of rapid solidification. Formation of banded structure was supposed to be resulted from the release of latent heat during solidification, which affect the stability of a planar liquid-solid interface.

• Earthquakes and Structures
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• v.7 no.6
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• pp.1241-1258
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• 2014

This is paper presents the results of an analytical study aimed at evaluating the effect of narrow-banded mainshock/aftershock seismic sequences on the response of structures built on very soft soil sites. Due to the scarce availability of recorded seismic sequences in accelerographic stations located in the lake-bed of Mexico City, artificial narrow-banded sequences were employed. In the first part of this study, a parametric investigation was carried out to identify the mainshock/aftershock ground motion features that have detrimental effects in the seismic performance of equivalent single-degree-of-freedom systems representative of framed-buildings that house standard and essential facilities. In the second part of this work, the seismic response of two (8- and 18-story) steel-moment resisting frames that house essential facilities is examined. It is concluded that buildings with fundamental periods of vibration longer than the dominant period of the mainshock can experience a significant increment in their inter-story drift demands due to the occurrence of an aftershock.

• Journal of Korean Association for Spatial Structures
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• v.17 no.1
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• pp.59-67
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• 2017

In this study, load transfer tests based on KCI-PS101 were conducted to verify the performance of spiral anchorage zone reinforcement for banded post-tensioning (PT) monostrands. With results, the compressive strength of spiral reinforcement was increased by about 20% than that of specimens with two horizontal steel bars and 8% than that of U-shaped bars. Advanced spiral reinforcement for corner increases compressive strength and can resist the spalling forces or fall-out effect at the corner by shear. The ratio of maximum load to amount of steel of the spiral reinforcement is about twice than that of U-shaped reinforcement. With increase of compressive strength capacity and improvement of constructability, the spiral reinforcement is considered to have advantages of promoting the performance of PT anchorage zone compared to conventional methods.

• Clinical and Experimental Reproductive Medicine
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• v.22 no.2
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• pp.109-122
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• 1995

A technique is described for producing high resolution G- and R-banded chromosomes in human peripheral lymphocyte cultures. Cultured lymphocyte cells were exposed to ethidium bromide ($10{\mu}g/ml$) and colcemid ($0.02{\mu}g/ml$) each for 2.5h and 0.5h prior to harvest for high resolution G-banded chromosomes. High resolution R-band patterns were obtained by BrdU substitution which was revealed by the fluorochrome-photolysis-Giemsa staining technique. These methods are easy to perform and highly reliable. The data on relative length of chromosomes at the four mitotic stages are presented in units of percentage of haploid autosome length. The characteristic patterns of GTG-bands (G-bands after trypsin and Giemsa) and RBG bands (R-bands after BrdU and Giemsa) were analyzed.

• Proceedings of the Korean Information Science Society Conference
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• 2001.10a
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• pp.592-594
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• 2001

두 문자열의 부분배치(local alignment)를 찾는 대표적인 알고리즘인 Smith-Waterman 알고리즘(SW 알고리즘)은 정규화된 최적부분배치를 찾지 못하는 단점이 있다. 최근에 fractional programming 기법을 이용하여 여러 번의 SW 알고리즘을 수행함으로써 정규화된 최적부분배티를 찾는 알고리즘이 제시되었지만 이는 매우 많은 시간이 걸린다. 본 논문에서는 fractional programming 기법을 이용하여 정규화된 최적부분배치를 찾는 알고리즘에, 완전매치(Exact Match)을 이용한 휴리스틱 기법인 Banded SW 알고리즘을 적용하여, 낮은 오차를 가지면서 실용적으로 매우 빠른 정규화된 최적부분배치를 찾는 알고리즘을 제시하고 이 알고리즘과 제시하고 이 알고리즘과 기존의 알고리즘을 직접 구현하여 실험한 결과를 비교 분석한다.

• Journal of the Korean Society for Precision Engineering
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• v.12 no.1
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• pp.15-21
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• 1995

Automatic monitoring of cutting process is one of the most important technologies for increasing the stability and the reliability of unmanned manufacturing system. In this study, the methods which use laser displacement signals and banded energy method are proposed to monitor chatter vibration in the turning process. From this method, the monitoring system of the chatter vibration was developed and investigated its practical possibility. As a result, it is shown by experiments that the chatter vibration can be detected accurately, and it can be widely used in most turning processes.

• Journal of Ocean Engineering and Technology
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• v.25 no.2
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• pp.120-126
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• 2011

The fatigue damages in structural details of offshore plants can be accumulated due to various environmental loadings such as swell, wave, wind and current. It is known that load histories acting on mooring and riser systems show stationary and ergodic bimodal wide-banded process. This paper provides refined approach to obtain time signals representing stress range histories from wide-banded bimodal spectrum which consists of ideally narrow-banded and fully separated two spectrums. Variations of the probabilistic characteristics for time signals according to frequency and sampling time increments are compared with the reference data to be the probabilistic characteristics such as zero-crossing period, peak period, and irregularity factor obtained from an assumed ideal spectrum. It is proved that the sampling time increment more affects on the probabilistic characteristics than frequency increment. The fatigue damages according to the frequency and sampling time increments are also compared with the ones with minimum increment condition which are thought to be exact fatigue damage. It is concluded that the maximum sampling time increment to obtain reliable time signals should be determined that ratio of applied maximum sampling time increment and minimum period is less than approximately 0.08.

• Parasites, Hosts and Diseases
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• v.45 no.3
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• pp.191-198
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• 2007

A total of 205 larval gnathostomes were collected from 18 (22.5%) of 80 red banded odd-tooth snakes, Dinodon rufozonatum rufozonatum, which had been smuggled from China and confiscated at Customs in Susan, Republic of Korea. In order to identify the species, some of the larvae were observed by a light microscope and a scanning electron microscope (SEM). The larvae were $2.18{\times}0.29mm$ in average size, and had a pair of lips at the anterior end, a muscular esophagus, 2 pairs of cervical sacs, and brownish intestines. The head bulb was characteristically equipped with 4 rows of hooklets; the average number of hooklets in each respective row was 38.6, 40.5, 41.5, and 43.7. In SEM views, the mouth evidenced a pair of lateral lips of equal size in a half-moon shape. Each lip featured a couple of labial papillae and a small amphid located between the 2 papillae. The hooklets on the head bulb had single-pointed, posteriorly-curved tips. The cuticular spines were larger and more densely distributed on the anterior part of the body, and decreased gradually in size and number toward the posterior body. On the basis of these morphological characteristics, the larvae were identified as the third stage larvae of Gnathostoma hispidum.