• Smart Structures and Systems
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• v.31 no.2
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• pp.113-130
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• 2023

Hybrid simulation (HS) has attracted community attention in recent years as an efficient and effective experimental technique for structural performance evaluation in size-limited laboratories. Traditional hybrid simulations usually take deterministic properties for their numerical substructures therefore could not account for inherent uncertainties within the engineering structures to provide probabilistic performance assessment. Reliable structural performance evaluation, therefore, calls for stochastic hybrid simulation (SHS) to explicitly account for substructure uncertainties. The experimental design of SHS is explored in this study to account for uncertainties within analytical substructures. Both computational simulation and laboratory experiments are conducted to evaluate the pseudo-random Sobol sequence for the experimental design of SHS. Meta-modeling through polynomial chaos expansion (PCE) is established from a computational simulation of a nonlinear single-degree-of-freedom (SDOF) structure to evaluate the influence of nonlinear behavior and ground motions uncertainties. A series of hybrid simulations are further conducted in the laboratory to validate the findings from computational analysis. It is shown that the Sobol sequence provides a good starting point for the experimental design of stochastic hybrid simulation. However, nonlinear structural behavior involving stiffness and strength degradation could significantly increase the number of hybrid simulations to acquire accurate statistical estimation for the structural response of interests. Compared with the statistical moments calculated directly from hybrid simulations in the laboratory, the meta-model through PCE gives more accurate estimation, therefore, providing a more effective way for uncertainty quantification.

• Journal of Life Science
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• v.12 no.6
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• pp.821-834
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• 2002

In order to measure the inter- and intraspecific genetic divergences within the genus Alexandrium, the variations within the internal transcribed spacer (ITS1 and ITS2) regions and 5.85 ribosomal RNA gene of eight Alexandrium species were examined for 33 strains from diverse geographical locations by direct sequencing. Five isolates of A. tamarense (AT-2, AT-6, AT-10, AT-A and AT-B) from Jinhae Bay, Korea were found to be completely identical to a Japanese strain OFX151-A. The length of the amplified ITSI-5.85-ITS2 region varied from 481 nucleotides (in A. margalefi) to 528 nucleotides (in A. affine CU1-1). ITS1 and ITS2 nucleotide lengths were negatively correlated, whereas a positive correlation was found between their G＋C content. The degree of sequence divergence ranged from 0.3% (1 bp) to a maximum of 53% (305 Up). Pairwise sequence comparisons revealed a small degree of divergence between A. tamarense and A. Pundyense isolates (1.2 - 2.3% ＝ 6-12 bp), but a high degree of divergence between A. tamarense and A. catenella (19.8% ＝ 102 bp), and between A. catenella and A. Pundyense (19.7%). Although most nodes were weakly supported by bootstrap values, some types tend to form independent molecular groups. A. catenella isolates also formed an independent molecular sub-group, with relaticula strong bootstrap values (94% or 85% and 79% or 98%, respectively in PAUP and NJ trees). Interestingly, A. cohorticula and A. frateculus always clustered within the same sub-group, this result being supported by strong bootstrap values. Our results indicate that the ITS regions provide useful informations on hierarchical population genetic structure and a high phylogenetic resolution in intraspecific and interspecific Alexandrium population.

• Journal of Korean society of Dental Hygiene
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• v.8 no.3
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• pp.85-98
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• 2008

This study is to enforce to ready basic data of effective dental education program and no smoking and no drinking program for high school students who do smoking and drinking, executed investigation by own recording way using smoking and questionnaire consisted of actual conditions and caries prevention awareness and dental health knowledge degree of drinking to some man high school. Analyzes result that total 487 people respond in SPSS WIN 13.0 programs and got following sequence. Result of this study is as following. 1. Mans high school students had more students who do not than a drinking student and main current received most soju. Third-year student appeared by thing which receive a lot of soju than 1 or 2 class student but different other difference was not seen by class. 2. Mans high school students had more students who do not than a smoking student and a student who smoke more than 3 years was the most. I can know was old since third-year student smokes than 1 or 2 class student. 3. It was not difference that keep in mind by drinking, smoking availability although there were many students who recognize that all of the on-time dental medical examination, sugar intake limitation, fluorine inclusion toothpaste, teeth fluorine application are seldom effective on caries prevention. 4. Recognized that right brushing is effective relatively on caries prevention. I was shown difference that recognized that righter brushing is effective on bad tooth courtesy call than a student who a student who do not smoke does, and keeps in mind according to smoking availability ($x^2$=6.78, p<0.05). 5. I knew best about question of 'A caries may not treat if is painless' among that question ask knowledge for a caries, and appeared by thing which do not know best about question of 'Know that method that supply fluorine in water'. 6. A student who do not drink general dental know-how for a caries was high knowledge degree for a caries than a drunk student but it was no difference that keep in mind by drinking availability. Also, a student who do not smoke by smoking availability was high knowledge degree for a caries than a done student but difference that keep in mind statistically was not seen. 7. It was no difference that keep in mind by drinking availability, but a student who do not smoke by smoking availability was high relation knowledge degree with food and a caries than a smoked student, and I was shown difference that keep in mind according to smoking availability(t=-2.03, p<0.05). 8. Awareness and synthetic estimation degree of knowledge degree a student who do not smoke than a smoked student mouth knowledge degree high, and I was shown difference that keep in mind according to smoking availability(t=-2.03, p<0.05). When see as result such as singularity, family, school, all social institutions may have to help by national business coming and try so that can become national business based on special know-how for development of effective and epoch-making education program as quickly as possible.

• Journal of Navigation and Port Research
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• v.36 no.4
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• pp.279-284
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• 2012

This study aims to identify the degree of safety when mariners take their actions in several different situations. We have carried out many experiments to observe mariners' behavior and then measured the safety level based on their actions to avoid dangerous situations of ships collision. One of the most important actions that mariners have to take, either as their daily routine or when they are in a collision situation and then want to avoid that situation is the lookout. In this paper, behaviors on the lookout have been defined as a standard sequence of three steps which are "time of first detection", "time of recognition as risky vessel" and "time of starting avoiding action", and the suitability and applicability of the definition have been shown. And also we propose the risk assessment on ships collision and the recommendation for reducing ships collision at sea. Some analyzing results and the application of the results are reported. By combining these knowledge and some systematic studies, we propose the risk assessment on ships collision and the recommendation for reducing ships collision at sea.

• Tunnel and Underground Space
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• v.12 no.4
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• pp.268-276
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• 2002

In this study, a 3D coordinate measurement system equipped with a laser displacement meter for digitizing rock joint surface was established and the digitized data were used to calculate several roughness parameters. The parameters used in this study were micro avenge inclination $angle(i_{ave})$, average slope of joint $asperity(SL_{ ave})$, root mean square of $i-angle(i_{rms})$, standard deviation of height(SDH), standard deviation of $i-angle(SD_i)$, roughness profile $index(R_P)$, and fractal dimension(D). The relationships between the roughness parameters based on the digitzation of the surface profile were analyzed. Since the measured value varied according to the degree of reflection and the variation of colors at the measuring point, rock joint surface was painted in white to minimize the influence of the surface conditions. The comparison of the measured values and roughness parameters before and after painting revealed the better consequence from measurement on the painted surfaces. Also, effect of measuring interval was studied. As measured interval was increased, roughness parameters were exponentially decreased. The incremental sequence of degree of decrease was $SDH\; i_{ave},\; i_{rms},\; SD_i,\;and\; R_ p-1$. As a result of comparison of parameters from pin-type measurement system and laser type measurement system, all value of parameters were higher when laser-type measurement system was used, except SDH.

• The Journal of Korean Academy of Prosthodontics
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• v.29 no.1
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• pp.39-52
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• 1991

The purpose of this study were to compare the condylar path and the anterior angle of glenoid fossae, and analyze the condylar path, and classify the patterns of condylar path. Thirty-three male and female dental students with normal occlusion and masticatory system ranging in age from 24 to 27, without present symptoms and any history of TM joint disturbance, were selected for this study. Then, sixty-six TM joint were examed. Transcranial radiographs of TM joint and Cephalometric radiographs under mandibular protrusive movement were obtained. They were taken at six positions on protrusive movement. The results obtained were as follows : 1. The sequence of the frequeny of condylar movement patterns were concave curve, "S"shape curve, convex curve, and reverse "S"shape. 2. The horizontal distance of the greatest changed position of condylar angle averaged 2.6mm. 3. The condylar path angle averaged 36.91 degree. 4. The angle of the anterior slope of glenoid fossae averaged 37.28 degree. 5. The distance fo condylar movement averaged 5.98mm and the distance of condylar horizontal movement averaged 4.71mm. 6. The slope of articular eminence was correlated to the condyalr path and three were no significant differences between right and left side of the anterior slope of articular eminence, and the condyalr path angle.

• Journal of the Korean Home Economics Association
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• v.30 no.1
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• pp.149-161
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• 1992

The purpose of this study is to analyze information search activity in purchasing behavior of household electric goods. Qusetionare survey method was used in this research. The sample was taken from 302 housewives living in Seoul, from 9th of Nov. to 20th of Nov, in 1991. Used statical methods were Frequency, Percentage, Crosstab, Anova, and Regression Analysis. The major findings are summarized as follows : 1) Component elements of information search : The means of acquiring information is that friends, neighbors, sales are most. A cause of choosing information is the sequence of satisfaction after using, easiness of interaction. The time in choosing goods is more month. 2) Component element of information search as social economic status housewife : children numbers and means of acquiring information(P<.01), education and a cause of choosing information(P<.05), life cost per month and a cause of choosing information(P<.05), social economic status and a time information search are significant. 3) A perception of risk as searching information : Among searching content of information a price influence a perception of risk. 4) Content of searching information and satisfaction of purchasing experience : Best choice is significant as quality of goods, difference of quality is significant as safety and degree of offering information is significant as a brand. 5) Satisfaction of purchasing experience following practical use of information : Best choice is significant as viewing of an exhibit and opinion of user. Difference of quality is not significant as any vairable. Degree of offer information influence searching pamphlet, searching an advertisement and opinion of user. 6) A perception of risk following source of an information : A perception of risk is most influenced by pamphlet.

• Structural Engineering and Mechanics
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• v.51 no.4
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• pp.531-546
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• 2014

In this paper the extension of a recently established energy-based pushover procedure in order to include the higher mode contributions to the seismic response of structures is presented and preliminary evaluated. The steps of the proposed methodology in its new formulation are quite similar to those of the well-known Modal Pushover Analysis. However, the determination of the properties of the 'modal' equivalent single-degree-of-freedom systems is achieved by a rationally founded energy-based concept. Firstly, the theoretical background and the assumptions of the proposed methodology are presented and briefly discussed. Secondly, the sequence of steps to be followed for its implementation along with the necessary equations is systematically presented. The accuracy of the methodology is evaluated by an extensive parametric study which shows that, in general, it provides better results compared to those produced by other similar procedures. In addition, the main shortcoming of the initial version of the methodology now seems to be mitigated to a large extent.

• Journal of the Institute of Electronics and Information Engineers
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• v.54 no.7
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• pp.115-124
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• 2017

The objective of study was to investigate the optimal echo phase for mouse brain enhancement scan using fast low angle shot (FLASH) sequence of 9.4T magnetic resonance imaging (MRI). For quantification based on this method, an MR phantom experiment and clinical research were done. The phantom experiment was conducted by fabricating three phantoms with different molar concentration of gadolinium to create changes in echo phase of 9.4T FLASH sequence used in mouse brain scans. In the phantom experiment, SSI was 25~27 [arbitrary units, a.u.] in each of 33 phases from $6{\pi}$ to $28{\pi}$, while RSP was 30~100 mmol. MPSI was 47~52 [a.u], while MPP, where MPSI is seen, was 0.8~9 mmol. EPMS was 80.8~108.0%, while ASIMP was formed between 21.1 and 31.8 [a.u]. In the clinical research, Finally, the occurrence rate of artifact that expressed -1 nd +1. The present study was able to quantify the degree of enhancement at FLASH sequence of 9.4T MRI, as well as identify the optimal echo phase during mouse brain enhancement scan.

• Journal of Animal Science and Technology
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• v.45 no.3
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• pp.473-482
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• 2003

In vivo protective and in vitro inhibitory activities of Lactobacillus casei YIT 9018. against typical enteritis causing Salmonella enteritidis KU101 and IgA level after challenge have been determined. In order to identify the strains of lactobacilli the sequences of 16S-23S rRNA intergenic spacer region were determined. All the test strains of Lactobacillus spp. inhibited Salmonella enteritidis, the intensity varied depending upon the species of lactobacilli. Effects on the survival rate of the mouse after challenge with Salmonella enteritidis KU101 on feeding Lactobacillus spp. have shown the highest survival rate in L. helveticus CU 631 followed by L. casei YIT 9018 and L. johnsonii C-4 and the lowest in control mice. The higher level of total Ig A concentration in the intestinal fluid of lactobacilli fed mice than control mice was observed. The sequences of 16S-23S rRNA intergenic spacer region of seven strains of Lactobacillus casei could be utilized as a strain identification, those sequences showed some degree of difference in homology.