• Structural Engineering and Mechanics
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• v.91 no.2
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• pp.123-133
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• 2024

The assessment of seismic behavior and seismic performance of ageing Sarıyar concrete gravity dam constructed on Sakarya River in Türkiye is the main focus of this paper. For this purpose, the impact of sediment domain, ageing of concrete material under the impact of chemical and mechanical actions, and dam-water-sediment interaction are included in the two-dimensional (2D) finite element (FE) model developed in FORTRAN 90 environment. In the FE model, the dam and age dependent sediment domains are modeled by solid elements, while reservoir domain is modeled by Lagrangian fluid elements. The radiation of reflected waves to the unbounded water domain is modeled by infinite Lagrangian fluid elements, while unbounded sediment domain is modeled by infinite solid elements. The coupled system was assumed to be under the simultaneous impact of Vertical (V) and Horizontal (H) ingredients of 1976 Koyna earthquake and the coupled system was analyzed in Laplace domain by direct method. Due to the deterioration of the concrete, the H and V displacement responses together with the fundamental period of the body, elongate throughout the lifetime and this reduce the seismic safety of the dam. It was deduced that the ageing dam body will not experience major damages under the Koyna earthquake both at the earlier and later ages. Furthermore, at the heel of the dam, the hydrodynamic pressure responses are decreased by rising the sediment domain depth.

• Proceedings of the Korea Fashion and Costume Design Association Conference
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• autumn
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• pp.142-144
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• 2004

• The Bulletin of The Korean Astronomical Society
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• v.40 no.2
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• pp.30.3-31
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• 2015

We present a kinematic analysis of 172 likely member galaxies of the Ursa Major Cluster. In order to understand the dynamical state of the cluster, we investigate the correlation of the cluster morphology with rotation, the velocity dispersion profile, and the rotation amplitude parallel to the global rotation direction. Both the minor axis and the rotation are very well-aligned with the global rotation axis in the outer region at half radius (> 0.5 $R_{max}$), but not in the inner region. The cluster exhibits low velocity dispersion and rotation amplitude profiles in the inner region, but higher in the outer. Both profiles exhibit outwardly increasing trends, suggesting an inside-out transfer of angular momentum of dark matter via violent relaxation, as revealed by a recent off-axis major-merging simulation. From Dressler-Schectman plots in the plane of galactic positions, and velocity versus position angle of galaxy, we are able to divide the Ursa Major Cluster into two substructures: Ursa Major South (UMS) and Ursa Major North (UMN). We derive a mass of $3.2{\times}10^{14}M_{\odot}$ for the cluster through the two-body analysis by the timing argument with the distance information (37 for UMN and 36 for UMS) and the spin parameter of ${\lambda}=0.049$. The two substructures appear to have passed each other 4.4 Gyr ago and are moving away to the maximum separation.

• Korean Chemical Engineering Research
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• v.56 no.2
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• pp.212-221
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• 2018

Process safety incidents and loss events can be prevented if we identify and adequately take measures on process safety incident precursors in a timely manner. If we look into and take action against the process safety hazard factors causing the incident in the refinery and petrochemical plant, major process safety incidents can be prevented through eliminating or decreasing hazardous factors. We conducted a survey for the major process safety incident precursor to look specifically into the potential process safety hazardous factors of refineries and petrochemical plants in the Yeosu chemical complex. A self-assessment checklist, which was published by Center for Chemical Process Safety "Recognizing catastrophic incident warning signs in the process industry" on major incidents warning sign, was used for the survey. Through this survey, the major process safety incident leading indicators in the process industry were found by process safety management elements, and each site and/or facility can use these leading indicators for activities for process safety incident prevention. In addition, we proposed action items required to eliminate the root cause of those process safety incident leading indicators.

• Journal of Korean society of Dental Hygiene
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• v.13 no.1
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• pp.61-68
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• 2013

Objectives : The purpose of this research is to identify the effect of Dental Hygienic students' level of satisfaction towards their major and sense of career exploration efficacy on their career exploration behavior so that the key findings of this research will help the university students to explore career related to their major and to assume rational attitude towards their career path. Methods : The study was conducted targeting 450 university students who are studying in the Department of Dental Hygienic at the four universities located in Daegu, Gyeongsangbuk-do and Chungcheongbuk-do. Data collection was carried out using the self-administered questions based on the use of structured survey questionnaire, and analysis was conducted using frequency analysis, descriptive statistics, ANOVA, correlation analysis, and multiple regression analysis. Results : 1. Total grade of the Dental Hygienic students' level of satisfaction towards their major was $3.36{\pm}.49$ points, while total grade of the sense of career exploration efficacy was $3.06{\pm}.46$ points. In case of the career exploration behavior, the total grade was $2.76{\pm}.53$ points. 2. In case of the level of satisfaction towards their major, there was a significant difference depending on the class, grade and motivation for admission. As for the sense of career exploration efficacy and career exploration behavior, there was a significant difference depending on grade. 3. Sense of career exploration efficacy and career exploration behavior demonstrated level of satisfaction towards their major manifested positive correlation. Sense of career exploration efficacy manifested positive correlation career exploration behavior. 4. As for the elements that affect Dental Hygienic students' career exploration behavior, they were level of satisfaction towards their major and sense of career exploration efficacy, and the explanatory power was 19.0%. Conclusions : It should be necessary to study the elements that affect Dental Hygienic students' career exploration behavior in greater depth using diverse methods and information in order to increase sense of career exploration efficacy so that the individual Dental Hygienic students can engage in detailed career exploration behavior for the sake of their career path.

• Ocean and Polar Research
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• v.36 no.4
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• pp.407-421
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• 2014

The benthic environmental impact experiment addresses environmental impacts at a specific site related to deep-sea mineral resource development. We have acquired several tens of multi- or box core samples at 31 sites within the Benthic environmental Impact Site (BIS) since 2010, aiming to examine the basic properties of surficial deep-sea sediment as a potential source for deep-water plumes. In this study, we present the geochemical properties such as major elements, rare earth elements (REEs), and heavy metal contents at the BIS. Such proxies vary distinctly according to the Facies association. The lithology of all core sediments in the BIS corresponds to both Association Ib and Association IIIb. The vertical profiles of some major elements ($SiO_2$, $Fe_2O_3$, CaO, $P_2O_5$, MgO, MnO) show noticeable differences between Association Ib and IIIb, while others ($Al_2O_3$, $TiO_2$, $Na_2O$, and $K_2O$) do not vary between Association Ib and IIIb. REEs are also distinctly different for Associations Ib and IIIb; in Association Ib, REY and HREE/LREE are uniform through the sediment section, while they increase downward in Association IIIb like the major elements; below a depth of 8 cm, REY is over 500 ppm. The metal enrichment factor (EF) evaluates the anthropogenic influences of some metals (Cu, Ni, Pb, Zn, and Cd) in marine sediments. In both Associations, the EF for Cu is over 1.5, the EF for Ni and Pb ranges from 0.5 to 1.5, and the EF for Zn and Cd are less than 0.5, indicating Cu is enriched but Zn and Cd are relatively depleted in the BIS. The vertical variations of geochemical properties between Association Ib and IIIb are shown to be clearly different, which seems to be related to the global climate changes such as the shift of Intertropical convergence zone (ITCZ).

• Analytical Science and Technology
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• v.13 no.6
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• pp.766-774
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• 2000

The major and trace constituents of Mongolian chromite were analyzed by ICP-AES. The dissolution procedures, mixed acid ($HClO_4+H_3PO_4$) digestion and fusion with $Na_2O_2$ flux, have been studied to dissolve the chromite. The optimum dissolution method was found to be a fusion with $Na_2O_2$ flux. The effect of large amount of Na on major and trace constituents was examined when these elements were determined by ICP-AES. There was no effect on major elements at a concentration of Na 250 mg/L solution. The emission intensity of trace constituents containing Na 1,250 mg/L decreased to 1.0-5.2% according to elements and wavelengths. The result of this method was compared with that of neutron activation analysis (NAA) to confirm the accuracy of this procedure. The results between two methods were in a good agreement within less than 5% for $Al_2O_3$, $Cr_2O_3$, MgO and -20 to 8% for Co, Mn, V, Zn, respectively.

• International Journal of Human Ecology
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• v.6 no.2
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• pp.85-94
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• 2005

The purpose of this study is to analyze the preference of spatial elements for common space planning in senior congregate housing. For the study, 500 potential consumer's residing in Seoul was surveyed using the questionnaire in the social survey methodology. As for the common spaces, gardens, treatment, and exercise rooms were preferred. A combination of both separate and group arrangement of the buildings was preferred, indicating that people wanted separation of the common space and the individual living units. Second, people preferred sharing parts of the common space with their neighbors and as is the traditional custom, preferred to take off their shoes at the entrance to individual units. Third, for the furniture and facilities, they wanted the manager room in the lobby, the small meeting rooms in the public dining room, a fitness center in the activity room, the rack or alcove to store items in front of an individuals unit in the hallway, a chair to sit down in the elevator, and the chair to rest on the stairway landing. Fourth, in terms of priority for planning the senior citizens' community housing, safety, familiarity like a regular home, reduced isolation and loneliness, sense of belonging, economic factors, aesthetic appreciation, daily life supplement, variety, and self-identity were answered in that order.

• Culinary science and hospitality research
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• v.13 no.1 s.32
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• pp.1-10
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• 2007

Co-branding of food courts is turning into a trend with the activation of recent entrance of famous restaurants into shopping departments and other large-size buildings. This research analyzes the effects of co-brand food courts on the choices of dining enterprises by dealing with the customers of these newly activated food courts in shopping malls and large-size buildings. By analyzing the effects of the present status of customers' using food courts according to the characteristics of their choices of dining enterprises, food and brand elements were found to have an effect on the restaurant brand recognition of food courts, and price factor was found to have an effect on an visitors' recommendation intension. Therefore, customers who set importance on food and brand elements tend to take the brand of food courts into consideration as well; therefore, the maintenance of food quality and strengthening of brand image are mandatory in case of food court operation.

• Journal of the Korean housing association
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• v.25 no.3
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• pp.131-143
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• 2014

The purpose of this study is to develop an operation manual of resident-driven community program by evaluating community program operation to realize a sustainable apartment complex and vitalize a community. To achieve this purpose, 8 community experts, who are in charge of 42 complexes of 7 autonomous districts among 25 districts in Seoul were interviewed from September 2013 to December 2013. Main results of the study are as follows. 1) Operational problems and improvements are deduced from evaluating operation process of community programs. It is found that smooth cooperation of main operators including a community vitalization association, a resident representative meeting and a control office is the most important. 2) Operation guideline for representative programs are suggested based on analysis of operational characteristics of 3 types of community programs; communication, recycling and environment management, according to program operation elements; material element, programming element, human element and finance element. 3) An operation manual of resident-oriented community program is presented after considering evaluation of operation processes and analysis of 3 types of operational elements of community programs.