• Journal of Korean Society of Transportation
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• v.35 no.4
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• pp.321-331
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• 2017

The objective of this study is to analyze the factors affecting the pedestrian accidents of roundabout near schools. To this end, this study has focus on the comparative analysis of pedestrian accidents across different school areas. The traffic accident data from 2007 to 2014 are collected from TAAS data set of Road Traffic Authority. To develop the pedestrian accident rate model, the linear regression model has been utilized in this study. 28 explanatory variables such as geometry and traffic volume factors are used. The main results are summarized as follows. First, the null hypotheses that the number of pedestrian accidents are the same are rejected. Second, 5 multiple linear regression accident models with higher statistical significance (adjusted $R^2$ of 0.651~0.788) have been developed. Third, while the common variables of 3 models (model I~III) related to school location are evaluated to be the pedestrian island, crosswalk, types of roundabout, elementary school and bus stop. Fourth, while the common variable of 3 models (model III~V) related to near school area or not is evaluated to be pedestrian island, type of roundabout, sidewalk, elementary school, speed hump, speed limit sign and number of entry lane. As a result, the installation of pedestrian islands and crosswalk might be expected to decrease the number of pedestrian accidents near schools.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.11 no.2
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• pp.1-10
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• 1989

The major causes of the facial bone fractures are fractures are automobile collision or other accident, and fights. Of the facial bone fractures, the nasal bone fractures are monst common. According to Schroeder et al., 50% of facial bone fractures are isolated fractures of the nasal pyramid. But the fractured nasal bone is not immediately treated as other facial bone fractures. And it is necessary to delay the treatment of the combined nasal bone fractures with other jaw bone fractures because of the difficult anesthetic techniques. Therefore there are many residual nasal deformities following a fracture; nasal hump, saddle nose and alar rim defect. Many authors have suggested the methods to correct the post-traumatic nasal deformities. We have treated several patients with several methods and this paper presents the operating methods and results.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.21 no.5
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• pp.869-875
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• 2017

Using TCAD simulation, performances of tunnel field-effect transistors (TFETs) was investigated. Drain current-gate voltage types of TFET structure such as single-gate TFET (SG-TFET), double-gate TFET (DG-TFET), L-shaped TFET (L-TFET), and Pocket-TFET (P-TFET) are simulated, and then as dielectric constant of gate oxide and channel length are varied their subthreshold swing (SS) and on-current ($I_{on}$) are compared. On-currents and subthreshold swings of the L-TFET and P-TFET structures with high electric constant and line tunneling were 10 times and 20 mV/dec more than those of the SG-TFET and DG-TFET using point tunneling, respectively. Especially, it is shown that hump effect which dominant current element changes from point tunneling to line tunneling, is disappeared in P-TFET with high-k gate oxide such as $HfO_2$. The analysis of 4 types of TFET structure provides guidelines for the design of new types of TFET structure which concentrate on line tunneling by minimizing point tunneling.

• Archives of design research
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• v.11
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• pp.48-58
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• 1995

In 1981. KOREA applied YEAR OF WORLD DISABLED DESIGNNATED BY UN as starting point to begin noticing disabled and gradually improve and understand the problems of the disabled.This study considering the income level and welfare level selected basic most widely used wheelchair as subject of study. Design Application of this study's main analysis are as follolVs 1. MAN-MACHINE INTERFACE STUDY ANALYSIS!Basic concept of wheelchair is for persons uncapable of move by sitting down. so main focus of study was considered on equipment which on chair. 2. WHEELCHAm MOVEMENT STUDY ANALYSISlThrough movement and test measurement which can be considered as basic study of Ergonomics, observe movement changes accordingly. 3. BACK(MAIN) WHEEL AND HANDRIM MOVEMENT ANALYSIS / Seat and wheel as the most important component of a wheelchair, study the relation of handrim and hand movement and test the most effective and comfortable handrim. Direction of the study was concerntrated on three areas, with results and information collected, would like to suggest design change of X type collapsible chair in areas of size of SEAT(air pocket type), HANDRIM(anti-slip hump), ARMHEST(transfer movement, rubber padding. accent), and HANDLE(adjustable, round type). The content started this study is only one small position of understanding the disabled. Also, the importance of one of many business of assisting disabled rehabilitation. (IJISABLED, REHABILITATION. APPROACH)

• Journal of Environmental Science International
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• v.14 no.8
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• pp.793-800
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• 2005

We isolated and identified microorganisms from the aerial environment of domestic museums. The fungi, Penicillium spp., Alternaria spp., and Cladosporium spp. were isolated in many museums. It seems that these fungi are related to biological degradation of textile remains. A total of 14 kinds of bacterial strains were isolated: Acinetobacter spp., Pseudomonas spp., Neisseria spp., Alcaligenes spp., Shigella spp., Klebsiella spp., Corynebacterium spp., Aerococcus spp., Bacillus spp., Micrococcus spp., Citrobacter spp., Erwinia spp., Salmonella spp., and Providencia spp. Acinetobacter spp., Pseudomonas spp., Neisseria spp., and Alcaligenes spp. were the predominate bacteria found in samples with a variety of bacteria. This suggests that there is a relationship between bacteria and the damage of textile remains. In the museum, we isolated Alternaria spp, Geotrichum spp., Penicillium spp. Acinetobacter spp., Pseudomonas spp., Alcaligenes spp. from the entrance, exhibit hall and storage, but they were found in smaller number and species in the exhibit cases and paulownia cases. We concluded that paulownia cases were not influenced by the microorganisms because of quality of care provided by the museum staff. Corynebacterium spp., and Bacillus spp. were not detected at the entrance and exhibit hall but were detected in paulownia cases. It is presumed that those bacteria did not flow in from outside, but resulted from contaminants in paulownia cases. In the distribution of microorganisms associated with textile remains, more fungi were detected than bacteria. Acinetobacter spp., Pseudomonas spp., and Neisseria spp., were isolated from silk items. Penicillium spp. and Cladosporium spp. were isolated in the silk and hump items. Aspergillus spp. and Penicillium spp. were isolated from the cotton items. On the other hands, there were no fungi strains in the wool items. Most of the isolated strains from textile remains were aerial microorganisms from the museum environment. These results suggest that textile remains were apt to contaminated by contact with the air.

• Bulletin of the Society of Naval Architects of Korea
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• v.6 no.1
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• pp.25-34
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• 1969

From viewpoints of over-all ship economy the straight framed V-bottom hull forms with chines are considered to be attractive even for usual commercial vessels, because increments of resistance over that of round hull forms, if any, can be well compensated with reduction in construction cost.[1] To investigate the influences of both prismatic coefficient and chine elevation on resistance performance, three models of straight-framed V-bottom hull forms which are similar to Prof. C. Ridgely-Nevitt's W-18, W-8, and W-20[2],[3] in size and hull form coefficients were tested at the SNU Ship Model Towing Tank for resistance measurements. They are of Cp=0.60, 0.65 and 0.70 and of ${\Delta}/(0.01L)^3=300$. Influence of variation of chine elevation on resistance performance were observed with the test results obtained at normal condition, and at the trimed by the stern by 2% and 4% of $L_{bp}$ at normal condition under same displacement. The hull form characteristics are shown in Table 1, and in Fig. 1, 2, 3, 4 and 5. The test results are shown in Fig 8, 9 and 10 in the form of Cr vs. $V/\sqrt{L}$ curves taking Cp as a parameter for normal condition, trim by the stern in 2% and 4% $L_{bp}$ at normal condition , respectively. Cr vs. $V/\sqrt{L}$ curves taking trim condition as a parameter are also shown in Fig 11, 12 and 13 for Cp=0.60 and 0.70, respectively. The best and the worst trim condition at given $V/\sqrt{L}$ in viewpoint of Cr are plotted for each Cp-value as shown in Fig 14, 15 and 16. From the above results the following conclusions are derived: (1) In general, the resistance performance of the straight-framed V-bottom hull forms are not inferior to those of round hull forms. At a certain range of $V/\sqrt{L}$ the former gives less resistance than the latter. (2) Regarding influences of Cp on Cr, it is observed that, at $V/\sqrt{L}$ less than about 0.925, the greater Cp-value gives the more increment of Cr, and that, at $V/\sqrt{L}$ greater than about 0.925 the smaller Cp-value gives the more increment of Cr. It is also noteworthy that the model of Cp=0.70 has remarkable hump on Cr vs. $V/\sqrt{L}$ curve between $V/\sqrt{L}=0.80$ and 0.90. (3) For higher speed within the test range, the chine elevation having the steeper slope around bow and the easier slope around amidship and stern, refered to watering, give the better results in resistance performance. (4) Assuming the chine elevations adopted for the tested models were not of the best, we would expect further improvement of resistance performance for such form. Hence, a systematic study on chine elevation is very disirable to prepare design data of general purpose for the such hull forms.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.38 no.6
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• pp.895-906
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• 2018

The improvement project for school zone in Korea is occurring mostly in kindergartens and elementary schools in which children are mainly active, and is being promoted as part of measures to prevent children's traffic accidents. However, since the study on the essential installation facilities and proper level of safety facilities for School zone is lacking, this study relatively evaluated the efficiency of safety facility installation using DEA (Data Envelope Analysis) and suggested improvement plan. We built the facilities and incident data for 28 school zones in Hwaseong City. Six major facilities (Raised intersection, Raised crosswalk, Protective fence, Skid Proof, Speed hump, Speed cameras) that have proven to be effective in the preceding research were analyzed as input factors. As a result of the analysis, only 12 out of 28 showed efficiency and 16 out of efficiency. Effective groups of school zones were found to have fewer installed Protective fences, Skid Proof, and Speed cameras installations than school zones classified as ineffective groups. Protective fences were found to be efficient even if only 47% of the total extension of the school zone was installed, and the number of slip prevention facilities was 8.7 per square km. The number of subjects to be compared is 28, so this study is limited to use as a relative efficiency evaluation index, and it can be grouped into nationwide units and efficiency evaluation can be done for each group.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.22 no.2
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• pp.755-765
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• 2021

The objectives of this study are to subdivide the group of elderly population into the liberation generation as a poor generation that experienced the barley hump, and the baby boom generation to verify differences in the mean of social capital and well-being between those groups of two generations, to verify the effects of social capital on the well-being, and then to review differences between those groups of two generations regarding the effects of subfactors of social capital on the well-being. This study collected and analyzed data from 200 people excluding missing values from the baby boom generation and liberation generation born in 1945-1963, in the D region from July 1st to July 31st, 2018. The main results of this study are as follows. in the results of comparatively reviewing the social capital having effects on the well-being of each group of liberation generation and baby boom generation, when relieving the statistical significance level to 90%, the network was working as a variable having effects on both groups. In this case, when mutually comparing the influence of regression coefficient as �� value, the network had a relatively larger effect on the well-being of the liberation generation.

• Korean Journal of Environmental Biology
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• v.41 no.1
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• pp.60-88
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• 2023

This study was conducted to investigate the vertical distribution and vascular plants in the Gakho mountain. Form the results of three field surveys from May 2022 to September 2022, a total of 478 total taxa, representing 426 species, 11 subspecies, 35 varieties, four forms, and two hybrids were identified, which were categorized in 282 genera and 94 families. We identified the elevational distribution ranges of 398 taxa of vascular plants. Among them, 19 taxa were endemic to Korea, one taxon was identified as a rare plant. The floristic target plants amounted to 72 taxa, specifically two taxa of grade V, two taxa of grade IV, 16 taxa of grade III, 27 taxa of grade II, and 25 taxa of grade I. Further, 71 taxa were identified as northern lineage plants. A total of 19 taxa of alien plants were identified, with a Naturalized Index of 4.0%, an Urbanization Index of 6.6%, and three plants that disturbed the ecosystem. The result of analyzing the pattern of species richness showed a reversed hump shape with minimum richness at mid-high elevation. A cluster analysis showed a high degree of similarity between adjacent elevation sections that are geographically adjacent with similar habitat environments. Warmth index in the Gakho mountain ranged from 57.2℃·month to 84.2℃·month. Our results provide basic data on vascular plants and valuable information on elevational distribution ranges of current plant species in the Gakho mountain, which could serve as a baseline for comparison of the shifts in elevation under future climate change.

• Journal of Korean Society of Forest Science
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• v.109 no.1
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• pp.1-22
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• 2020

In order to evaluate the vertical distribution and distributional pattern of vascular plants in the Samga district of Sobaeksan National Park, vascular plants were surveyed along a hiking trail from the Samga Tour Support Center to the top of a mountain. The elevation range was divided into 11 sections with 100 m intervals from 400 m to 1439 m above sea level.A total of 375 taxa were listed, comprising 92 families, 235 genera, 332 species, 3 subspecies, 37 varieties, and 3 forms. The pattern of species richness along the elevational gradient showed a reverse hump-shaped trend. The species distribution pattern was positively correlated with the soil exchangeable cations Ca²⁺ and Mg²⁺, soil pH, available phosphate, and the warmth index. Furthermore, slope, soil moisture content, and soil exchangeable cations were significantly correlated with species distribution. DCA grouped herb species into two groups. Stands of each section were sequentially arranged from 400 m to 1500 m along an altitudinal gradient. Soil moisture content, soil pH, soil K²⁺ and Na²⁺, available phosphate, and slope were significantly correlated with stand distribution. This study provides important data that could be useful for conservation and the sustainable use of biodiversity in the study area. In order to understand the ecological and environmental characteristics and distribution of plant species, it will be necessary to continuously develop relative studies with continuous monitoring.