• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.37 no.5
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• pp.293-302
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• 2019

In mountain accident events, it is important for the search team commander to determine the search area in order to secure the Golden Time. Within this period, assistance and treatment to the concerned individual will most likely prevent further injuries and harm. This paper proposes a method to determine the search priority area based on missing persons behavior and missing persons incidents statistics. GIS (Geographic Information System) and MCDM (Multi Criteria Decision Making) are integrated by applying WLC (Weighted Linear Combination) techniques. Missing persons were classified into five types, and their behavioral characteristics were analyzed to extract seven geographic analysis factors. Next, index values were set up for each missing person and element according to the behavioral characteristics, and the raster data generated by multiplying the weight of each element are superimposed to define models to select search priority areas, where each weight is calculated from the AHP (Analytical Hierarchy Process) through a pairwise comparison method obtained from search operation experts. Finally, the model generated in this study was applied to a missing person case through a virtual missing scenario, the priority area was selected, and the behavioral characteristics and topographical characteristics of the missing persons were compared with the selected area. The resulting analysis results were verified by mountain rescue experts as 'appropriate' in terms of the behavior analysis, analysis factor extraction, experimental process, and results for the missing persons.

• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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• 2002.05a
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• pp.185-190
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• 2002

It has made a special study of bending behavior of F.R.P sandwich beams with bonded 2nd-reinforced plies. Specimens were made of Chopped Mat 300-450, Roving Clothes 570 and the mixture weight ratio of Resin versus hardener was 55:45 for bending tests. it was fabricated by hand lay-up method, hardened for 24 hours in nature, cut specimens according to ASTM standard C393-94 Knowing exact behavior of bonded area's stress and strain depends upon various bonded F.R.P length on which covered lap joint. We also considered shear stress in adhered area and have done computational estimation by ANSYS as well. This study reveals that the length of plies covered lap joint are longer, Failure stresses are remarkably larger.

• Korean Journal of Community Nutrition
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• v.22 no.4
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• pp.336-346
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• 2017

Objectives: The study was performed to investigate the relationship between snack intake and oral health behavior in middle school students in Gyeonggi-do area. Methods: The survey questionnaire was recorded by middle school students from July 6 to August 24, 2011. The questionnaire included items on general characteristics, snack intake status, and oral health behavior. Among collected survey questionnaire, a total of 620 questionnaires (320 males and 300 females) were analyzed using SPSS 15.0 program. Results: Frequencies of snack and beverage intakes were significantly higher in males than in females (p < 0.001). Oral health behavior was significantly higher in students with lower snack intake compared to those with higher or average snack intake (p < 0.05). Oral health behavior for tooth brushing and toothbrush care were significantly higher in females than in males (p < 0.05). Conclusions: Oral health behavior score that reflected better oral health of the subjects were higher as the snack intake was lower. Oral health behavior score was higher in females than in males. We conclude that the contents for oral health and nutrition education focused on snack intake need to be developed to induce changes in oral health behavior in middle school students.

• Geomechanics and Engineering
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• v.5 no.3
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• pp.241-261
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• 2013

The bearing mechanism of pile during installation and loading process which controls the deformation and distribution of strain and stress in the soil surrounding pile tip is complex and full of much uncertainty. It is pointed out that particle crushing occurs in significant stress concentrated region such as the area surrounding pile tip. The solution to this problem requires the understanding and modeling of the mechanical behavior of granular soil under high pressures. This study aims to investigate the sand behavior around pile tip considering the characteristics of sand crushing. The numerical analysis of model pile loading test under different surcharge pressure with constitutive model for sand crushing is presented. This constitutive model is capable of predicting the dilatancy of soil from negative to positive under low confining pressure and only negative dilatancy under high confining pressure. The predicted relationships between the normalized bearing stress and normalized displacement are agreeable with the experimental results during the entire loading process. It is estimated from numerical results that the vertical stress beneath pile tip is up to 20 MPa which is large enough to cause sand to be crushed. The predicted distribution area of volumetric strain represents that the distributed area shaped wedge for volumetric contraction is beneath pile tip and distributed area for volumetric expansion is near the pile shaft. It is demonstrated that the finite element formulation incorporating a constitutive model for sand with crushing is capable of producing reasonable results for the pile loading problem.

• Geomechanics and Engineering
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• v.30 no.4
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• pp.373-382
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• 2022

Unsaturated soil at high suctions is widespread. Many civil engineering projects are related to the hydro-mechanical behavior of unsaturated soils at high suctions, particularly in arid and semiarid areas. To investigate water retention behaviors of nine clayey soils (one is classified as fat clay and the others are classified as lean clay according to the unified soil classification system), the high suction (3.29-286.7 MPa) was imposed on the specimens at zero net stress by the vapor equilibrium technique. In this paper, the effect of void ratio on the water retention behavior at high suction was discussed in detail. Validation data showed that soil types, i.e., different mineralogical compositions, are critical in the soil water retention behavior at a high suction range. Second, the hysteresis behavior at a high suction range is mainly related to the clay content and the specific surface area. And the mechanism of water retention and hysteresis behavior at high suctions was discussed. Moreover, the maximum suction is not a unique value, and it is crucial to determine the maximum suction value accurately, especially for the shear strength prediction at high suctions. If the soil consists of hydrophilic minerals such as montmorillonite and illite, the maximum suction will be lower than 10⁶ kPa. Finally, using the area of hysteresis to quantify the degree of hysteresis at a high suction range is proposed. There was a good correlation between the area of hydraulic hysteresis and the specific surface area.

• Tunnel and Underground Space
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• v.24 no.5
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• pp.344-353
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• 2014

In this study, the behavior of rock pillar in the diverging area of road tunnel was assessed by using a three dimensional numerical analysis. Based on parameters affecting the behavior of rock pillar, different safety factors according to pillar width, depth and rock conditions were evaluated. It turned out that as the pillar width increases, the change curve of safety factors in accordance with depth and rock conditions shows more of the nonlinear behavior. By the assessment of the minimum safety factor, a safety factor chart on the behavior of rock pillar in the diverging area of road tunnel was suggested.

• The Korean Journal of Community Living Science
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• v.22 no.4
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• pp.509-518
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• 2011

This study was intended to investigate dietary behavior, health related behavior and the effects of nutrient intake of female college students. Dietary behavior, health related behavior and the perception of the body conditions were surveyed with anonymous questionnaires, and 24hrs recall method for nutrient intake was obtained from 161 female college students in Chungbuk area. The mean height and weight of the subjects were $161.4{\pm}5.0$cm and $53.8{\pm}7.4 $kg, respectively. The dietary behavior of female college students was generally inadequate. More specifically, irregularity of meals, indifference of dietary balance, and skipping breakfast, showing $4.77{\pm}2.20$for dietary behavior score, $11.76{\pm}3.89$ for DVS and $3.58{\pm}0.82$ for DDS, respectively. It was found that almost 63% of subjects did not anything for health care and the frequency of exercise of subjects was low. The perception of body conditions of the subjects seemed to be generally positive. However, satisfaction levels on body shape was very negative showing that only 12.4% of subjects answered as 'very satisfied' and 'satisfied'. When nutrient intake of the female college students was compared with Dietary Reference Intake for Korean, folate(45%), potassium(55%), vitamin C(59%), Ca(72%), fiber(72%), Fe(79%) and energy(80%) were found to be insufficient. But protein(138%), P(122%) and Na(179%) were found to be oversupplied. The nutrient intake of fiber, plant Ca, vitamin A, ${\beta}$-carotene, vitamin B6, vitamin C, folate and vitamin E were significantly higher, and those of Fe, Zn and protein were a little high in the high score group of dietary behavior. Also Food group intake, DDS and DVS were higher in the high score group of dietary behavior.

• Journal of the Korean BIBLIA Society for library and Information Science
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• v.28 no.2
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• pp.119-135
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• 2017

Information behavior is an important area of research in library and information science (LIS) that has evolved over the last 75 years. The aim of this study is to investigate the recent trends of information behavior research by providing insights into emerging topical areas within information behavior. To conduct this study, the bibliographic data from Scopus was used, and the trends of information behavior were traced by using variations of key terms used in information behavior research, such as "information behavior", "information seeking behavior", and "information needs." In addition, the trends were analyzed in terms of content words in the title, highly cited journal articles, disciplinary categories, and author keywords. Information behavior research has its roots in LIS, but the findings of the study reveal that information behavior has expanded to other disciplines by intersecting a variety of topical areas. In particular, this study showed that information behavior in the health/medicine domain has become a predominant emerging topical area of research. In order to enhance our understanding of complex human behavior, future research should focus more on interdisciplinary aspects by measuring the scope of information behavior.

• Journal of the Korean Society for Precision Engineering
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• v.15 no.10
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• pp.113-119
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• 1998

Ship structures and aircraft structures are consisted of thin sheet alloy, so it is very important to understand the characteristics of fatigue crack propagation of that material and to establish the data base. The data for fatigue crack propagation behavior scatter very much even under identical experimental conditions with constant loading. The behavior of fatigue crack propagation under regular and irregular cyclic loadings is known to be highly affected by complicated factors such as plastic zone developed at the vicinity of crack tip and reduction of cross sectional area. In this paper, the controlled stress amplitude and overload fatigue crack propagation tests have been conducted to investigate the effect of varying factors such as plastic zone size near the crack tip and area reduction factor (AF) on the fatigue crack propagation behavior A better simulation of fatigue crack propagation behavior is found to be obtainable by using Wheeler and Willenborg models with AF effect.

• Proceedings of the Korea Concrete Institute Conference
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• 2001.11a
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• pp.197-202
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• 2001

It is necessary to Investigate long-term behavior of vertical members such as column and shear wall because the long-term behavior induces the serviceability problem of reinforce-concrete structures. However, the long-term behavior on shear wall has not been fully studied. Experimental works are performed to understand the time dependent behavior of shear wall, especially the effect of loading area in this research. Three different types of cross sections are adopted, i.e., 10$\times$10 cm, 10$\times$30 cm, and 10$\times$50 cm with the same loading area of 10$\times$10 cm. The creep strains were different from point to point in the section of the shear wall specimen because of the nonlinear stress distribution. The effect of the nonlinear stress distribution was larger in the specimen with the larger width.