• Earthquakes and Structures
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• v.9 no.5
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• pp.999-1028
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• 2015

Despite the fact that the fundamental period appears to be one of the most critical parameters for the seismic design of structures according to the modal superposition method, the so far available in the literature proposals for its estimation are often conflicting with each other making their use uncertain. Furthermore, the majority of these proposals do not take into account the presence of infills walls into the structure despite the fact that infill walls increase the stiffness and mass of structure leading to significant changes in the fundamental period numerical value. Toward this end, this paper presents a detailed and indepth analytical investigation on the parameters that affect the fundamental period of reinforce concrete structure. The calculated values of the fundamental period are compared against those obtained from the seismic code and equations proposed by various researchers in the literature. From the analysis of the results it has been found that the number of storeys, the span length, the stiffness of the infill wall panels, the location of the soft storeys and the soil type are crucial parameters that influence the fundamental period of RC buildings.

• Hwankyungkyoyuk
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• v.23 no.4
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• pp.32-43
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• 2010

This study was performed to know about the conformity tendencies of adolescent and adult groups based on lectures of the expert on the topic 'the cicada'. Characters of each lecture were 'he pure natural science', 'positiveness', 'negativeness' and 'neutrality,' and then attitude changes on the cicadas were investigated with a questionnaire. Consequently, half of the adolescent and adult groups thought of the cicadas' sounds as 'noise' through mass communications respectively. They had a neutral attitude, neither positive nor negative, on cicadas' sounds in the beginning. Attitudes of the people on the cicada, however, were changed positively only with a pure natural science lecture. In this case, the adolescent group was more prevalented by the lecture than the adult group. In other words, the positive-based lecture affected them positively, while the negative-based lecture affected them negatively. The conformity tendencies of adolescent groups participating in the positive-based lecture were substantial. In conclusion, as we can see from the so-called Kohlberg's 'stages of moral development', conformity tendencies of attitudes towards cicadas' sounds were generally much more prevalent in the adolescent group, compared with the adult group, even though there are some differences in subcategories.

• 한국태양에너지학회:학술대회논문집
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• 2009.11a
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• pp.86-91
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• 2009

In this paper, we analyze the Transition of Isc by natural solar spectrum of c-Si and a-Si PV module. Commonly, performance of photovoltaic (PV) module is estimated under the standard test condition (STC). That is, solar irradiance $1kW/m^2$, solar spectrum distribution: AM1 5G, module temperature $25^{\circ}C$ This means it rarely meets actual outdoor conditions. The solar spectrum always changes. So it is rare to fit the standard solar spectrum AM1 5G defined in ASTM G173-03 or IEC 60904-3. Thus spectral response of PV module is different depending on the material. so we estimated the variation of Isc at every minutes by comparing c-Si PV module with a-si PV module for outdoor conditions.

• Proceedings of the KSR Conference
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• 2006.11b
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• pp.1115-1122
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• 2006

The railway design trends has been developed by the change of the society and culture through the consideration of the history of railway. The railway design trends is as the vehicles in the external form of railways, instantly means to plan and create the value added something like the form of the exterior design. The railway design has been changing form instinctive methods to settle the mass transport of the early days, to sensitive methods to pursue the railway culture centering around human being. As dividing by the style's change of railway in image scale aspects between 1800's and 2005 according to the life environment into the external nation, there are big differences so that is to study the development history of the railway design accordingly each nation (United Kingdom, Germany, France, Japan) and the style's change, to confirm into the design applied in society and culture needs, and to analyze by a year in changes of the environment and the railway design history. This paper analyzed railway introduced as railway models by top 4 nation (United Kingdom, Germany, France, Japan) in the past years(1800-2005) for their railway design trends by image scale positioning.

• Transactions of the Korean Society of Mechanical Engineers
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• v.12 no.6
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• pp.1390-1398
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• 1988

The purpose of this study was experimentally to investigate the disintegration process and disintegration mechanism when co-axial air flows vertically for the longest smooth liquid jet. These were affected by liquid velocity, air velocity, air-to-liquid diameter ratio, nozzle shape, and air-liquid contacting position. That is, this process of disintegration of the liquid jet was similar to that occurred when liquid pressure was increased. At Reynolds number of 10, 000 and below, the changes in the breakup length represent different tendency according to liquid flow rate. The influence of air flow on the disintegration of liquid jet was different according to air-to-liquid diameter ratio, air orifice diameter, nozzle shape and contacting position of liquid and air. In particular, when the tip of liquid nozzle was inside the air orifice, the effect of air flow was the larger than outside the air orifice. The effect of liquid mass flow rate on the change rate of the breakup length was also different.

• Journal of the Korean Society of Food Culture
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• v.30 no.6
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• pp.825-833
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• 2015

This study was conducted to investigate the effectiveness of a nutrition and exercise education program on weight control and nutrition knowledge. The nutrition-exercise educational period was 12 weeks. The subjects were 160 adult women with an average age of 48.1 years. We investigated general characteristics, diet history, eating habits, and intake frequencies of six food groups by survey. A total of 94 women among the subjects participated in the pre and post nutrition knowledge evaluations and anthropometric data assessment. After the program, body weight, body mass index (BMI), and waist circumference significantly decreased. Further, % of body fat decreased, but not significantly. BMI significantly decreased (p<0.001) from 25.14 to $24.80kg/m^2$, and waist circumference significantly decreased (p<0.001) from 79.72 to 77.63 cm. The nutrition knowledge scores of subjects significantly increased (p<0.001) from 8.01 to 9.03. However, there was little change in employment. These results suggest that the nutrition-exercise education program may improve obesity index and nutrition knowledge. However, it is necessary to develop a specialized weight control program for workers.

• Preventive Nutrition and Food Science
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• v.19 no.4
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• pp.314-320
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• 2014

Flavor quality of Liriopis tuber tea that was made using a steaming process was studied by measuring changes in headspace volatile compounds. Headspace volatile compounds of the prepared samples were isolated, separated and identified by the combined system of purge & trap, automatic thermal desorber, gas chromatography, and mass selective detector. As steaming frequencies were increased, the area percent of aldehydes decreased from 32.01% to 3.39% at 1 and 9 steaming frequency times, respectively. However, furans and ketones increased from 18.67% to 33.86% and from 9.60% to 17.40% at 1 and 9 times, respectively. The savory flavor of Liriopis tuber tea was due to a decrease in aldehydes contributing a fresh flavor at the 1st steaming process and newly generated furans from nonenzymatic browning with repeated steaming frequencies. These results will provide basic information for quality control of the newly developed Liriopis tuber tea.

• Journal of Microbiology and Biotechnology
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• v.12 no.2
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• pp.228-234
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• 2002

Bacillus subtilis CAU131 (KCCM 10257) isolated from a fermented shrimp product produces subtilein, tentatively named as a bacteriocin, which exhibited a bactericidal effect against closely related species such as Bacillus subtilis ATCC 6633, Bacillus cereus ATCC 11778, and several other strains of Bacillus sp. The purification of the subtilein was achieved by applying a mono-Q anion exchange chromatography on FPLC and $C_18$ reverse-phase chromatography on HPLC. After purification, specific activity of subtilein was increased about 3,000-fold compared with culture broth and its molecular mass was about 5,000 Da on SDS-PAGE. The antimicrobial activity of subtilein was well maintained at acidic and neutral pHs between 3 and 8. Subtilein was relatively heat stable, and its antimicrobial activity remained for 2 h at $80^{\circ}C$. However, the activity was reduced after heating at $100^{\circ}C$, and about $80\%$ of the activity was found after 1 h incubation at $100^{\circ}C$. The treatment of Bacillus subtilis ATCC 6633 with subtilein led to morphological changes in stationary-phase cells and most cells appeared to be lysed.

• Journal of Microbiology and Biotechnology
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• v.12 no.2
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• pp.258-267
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• 2002

A flux determination methodology has been built which enables to develop constrained stoichiometric relationships and metabolic balances. The analysis differs from those developed for anaerobic growth conditions in that cell mass formation is a significant sink for carbon. When combined with experimental measurements, a determined system of equations results yielded tricarboxylic acid (TCA) cycle and glycolytic fluxes. The methodology was implemented to determine the fluxes of E. coli B/r and K12, and it was found that as the growth rate in a glucose minimal medium increased, the cells became increasing glycolytic and the TCA fluxes either leveled off or declined. The pattern identified for the TCA fluxes corresponded to ${\alpha}$-ketoglutarate dehydrogenase's induction-repression pattern, thereby suggesting that the induction-repression of the enzyme could result in significant flux changes. When the minimum flux solution was contrasted to the glycolytic and TCA fluxes determined, two observations were made. First, the minimum flux could provide the cell's biosynthetic ATP requirements. Second, at a high growth rate in a glucose medium, the excess glycolytic flux exceeded that of the TCA cycle, which appeared to more closely match the biosynthetic needs.

• Smart Structures and Systems
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• v.14 no.2
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• pp.159-189
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• 2014

One of the most important requirements in the evaluation of existing structural systems and ensuring a safe performance during their service life is damage assessment. Damage can be defined as a weakening of the structure that adversely affects its current or future performance which may cause undesirable displacements, stresses or vibrations to the structure. The mass and stiffness of a structure will change due to the damage, which in turn changes the measured dynamic response of the system. Damage detection can increase safety, reduce maintenance costs and increase serviceability of the structures. Artificial Neural Networks (ANNs) are simplified models of the human brain and evolved as one of the most useful mathematical concepts used in almost all branches of science and engineering. ANNs have been applied increasingly due to its powerful computational and excellent pattern recognition ability for detecting damage in structural engineering. This paper presents and reviews the technical literature for past two decades on structural damage detection using ANNs with modal parameters such as natural frequencies and mode shapes as inputs.