• Journal of Korean Society of Transportation
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• v.29 no.6
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• pp.97-106
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• 2011

Mode choice model is an essential element for estimating- the demand of new means of transportation in the planning stage as well as in the establishment phase. In general, current demand analysis model developed for the mode choice analysis applies common parameters of utility function in each region which causes inaccuracy in forecasting mode choice behavior. Several critical problems from using common parameters are: a common parameter set can not reflect different distribution of coefficient for travel time and travel cost by different population. Consequently, the resulting model fails to accurately explain policy variables such as travel time and travel cost. In particular, the nonlinear logit model applied to aggregation data is vulnerable to the aggregation error. The purpose of this paper is to consider the regional characteristics by adopting the parameters fitted to each area, so as to reduce prediction errors and enhance accuracy of the resulting mode choice model. In order to estimate parameter of each area, this study used Household Travel Survey Data of Metropolitan Transportation Authority. For the verification of the model, the value of time by marginal rate of substitution is evaluated and statistical test for resulting coefficients is also carried out. In order to crosscheck the applicability and reliability of the model, changes in mode choice are analyzed when Seoul subway line 9 is newly opened and the results are compared with those from the existing model developed without considering the regional characteristics.

• Journal of Korean Society of Transportation
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• v.27 no.2
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• pp.35-46
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• 2009

This paper presents an evaluation index for the supply levels of pedestrian facilities in residential area planning. The pedestrian facility supply levels reveal the quality of a residential area, and can be associated with the resident living standards and satisfaction, pedestrian safety levels, and the effectiveness of the construction cost. This research conducted multifaceted procedures for the index development, and these procedures start first by identifying dominant influencing factors on pedestrian travel demand by reviewing the final reports of site planning in more than eight already-completed residential development sites. Second, based on the Space Syntax model, which was initially developed in the UK by establishing statistical relationships among an integration index, population size (persons/day), and the total development area, this research formulated a set of pedestrian demand estimation models. Then these models were utilized in forming a pedestrian facility supply index by integrating the new models and their results with the available accepted practice in the residential planning sector. This was necessary because planners want to understand the total supply level of pedestrian facilities in a residential area during the initial design stage. Finally, to test the model validity in satisfying pedestrian satisfaction, the research included a resident satisfaction interview, and it was revealed that the evaluation index developed in this research could provide planners and engineers with more promising results. It is therefore anticipated that this research can be of service when designing pedestrian facilities in future residential area planning and design activities.

• Korean Journal of Psychosomatic Medicine
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• v.25 no.1
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• pp.27-32
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• 2017

Objectives : The purpose of this study was to determine the association between serum lipid profiles and depression according to gender difference. Methods : This retrospective cohort study included 27,452 subjects(15044 men and 12408 women) who underwent health examination. The duration was from January 2013 to December 2013. We estimate the correlation between serum lipid profile and Beck Depression Inventory(BDI) scores. We compare the effect size using beta coefficient. Results : In men, serum Triglyceride level was correlated positively with BDI scores(r=0.020, p<0.01). Serum LDL-C and HDL-C were negatively correlated with BDI scores(r=-0.015, p<0.01 ; r=-0.016, p<0.05). In women, Triglyceride level was also correlated positively with BDI scores(r=0.020, p<0.01), Serum HDL-C were negatively correlated with BDI scores(r=-0.019, p<0.01). There was no statistical significance between Serum LDL-C and Beck Depression Inventory(BDI) score. Conclusions : Both men and women had more depressive symptoms when they had low serum HDL-C level or high serum Triglyceride level. The depression symptoms were more severe when serum LDL-C level was low only in men.

• Journal of the Korean association of regional geographers
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• v.18 no.4
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• pp.464-472
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• 2012

To assess the space-time clustering of FMD(Foot-and-Mouth Disease) epidemic occurred in Korea between November 2010 to April 2011, geographical information system (GIS)-based spatial analysis technique was used. Farm address and geographic data obtained from a commercial portal site were integrated into GIS software, which we used to map out the color-shading geographic features of the outbreaks through a process called thematic mapping, and to produce a visual representation of the relationship between epidemic course and time throughout the country. FMD cases reported in northern area of Gyounggi province were clustered in space and time within small geographic areas due to the environmental characteristics which livestock population density is high enough to ease transmit FMD virus to the neighboring farm, whereas FMD cases were clustered in space but not in time for southern and eastern area of Gyounggi province. When analyzing the data for 7-day interval, the mean radius of the spatial-time clustering was 25km with minimum 5.4km and maximum 74km. In addition, the radius of clustering was relatively small in the early stage of FMD epidemic, but the size was geographically expanded over the epidemic course. Prior to implementing control measures during the outbreak period, assessment of geographic units potentially affected and identification of risky areas which are subsequently be targeted for specific intervention measures is recommended.

• Korean Journal of Environmental Biology
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• v.24 no.4
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• pp.372-379
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• 2006

In order to study temporal fluctuation and ecological characteristics of Noctiluca scintillans, its abundance was investigated in correlation with water temperature, salinity, precipitation, chlorophyll a concentration and copepods abundance in the coastal waters of Incheon from January 1999 to December 2000. N. scintillans was seasonally abundant during spring and autumn with temperature ranging from 10.3 to $21.5^{\circ}C$, but depleted in winter and summer. Low temperature below $4.5^{\circ}C$ in winter and low salinity due to high rainfall in summer led N. scintillans to disappear. A Cross Correlation Analysis (CCA) showed that chlorophyll a concentration was positively correlated with abundance of N. scintillans at the time lags of 10 days. This suggests that phytoplankton may be a contributing factor for increasing abundance of N. scintillans. During spring, eggs of Acartia hongi were found in 2.9 to 21.1% of individuals of N. scintillans. It was deduced that 1.2 to 49.5% of the eggs produced by A. hongi was preyed upon by N. scintillans. Therefore, N. scintillans may control the population size of initial developmental stage of A. hongi in the costal waters of Incheon.

• Clinics in Shoulder and Elbow
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• v.13 no.1
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• pp.86-91
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• 2010

Purpose: To introduce mini-open rotator cuff repair using the anterolateral approach and evaluate its clinical outcomes and effectiveness. Materials and Methods: 59 consecutive cases of rotator cuff tearing which were treated with mini-open repair utilizing the anterolateral approach were evaluated. The population comprised 39 men and 20 women, with an average age of 56.6 years. An average follow-up time period was 26 months. Clinical outcomes were analyzed based on VAS, ADL, and ASES scores. Results: The average respective VAS, ADL, and ASES scores improved from 7.04, 12.37, and 35.32 preoperatively to 1.02, 27.20, and 90.08 postoperatively (p=0.000). There were 41 excellent, 11 good, 2 fair, and 5 poor results. There were satisfactory results in 52 cases (88.1%). There were no statistically significant differences between the final ASES scores and age, sex, duration of symptoms, tear size, and preoperative stiffness (p>0.05). Conclusion: Mini-open rotator cuff repair using the anterolateral approach effective in providing better visualization.

• Korean Institute of Interior Design Journal
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• v.23 no.3
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• pp.173-180
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• 2014

Dwelling connotes characteristics like social and cultural and technical climatic conditions, lifestyles and demands of regions, and especially, apartment, as one of dwelling types, shows various aspects of modern society. With the economic development centering on large cities, apartments have been established as universal housing forms in Seoul and Shanghai. The deepening of economic development in cities has increased small households consisting of one or two persons by affecting the population and household structure, and they've become information consumer groups. This has also influenced the size of apartment and increased the demand for small-sized housing. If the floor area is small, it is possible to use space widely according to the plan composition, so there is a need for floor planning to understand natural environment, physical environment and residents.This study compared and analyzed plan compositions of small-sized apartments which have been parceled out for the recent three years in Seoul and Shanghai. This study aims to understand housing cultures and users in the two countries depending on natural environments, living habits and spatial functions by analyzing common points and differences of public spaces like living room, dining room and kitchen, and private spaces like bedroom which have absolute effects on room arrangement and traffic line. The study results are as follows. From the perspective of natural environments, in Seoul, two-sided open cross-ventilation structure where is favorable to lighting and ventilation, occupied the biggest proportion of public space, while in Shanghai, most public spaces had lighting and ventilation structures through windows in each room. In Seoul, 3R type occupied the largest proportion of private space(87.7%), and privacy was maintained and space scale was adjusted using spaces with diverse functions such as bathroom in the couple bedroom, dress room and powder room and variable walls. But 2R type occupied the largest proportion of private space(60.2%) in Shanghai, and they emphasized private space and privacy of each room depending on major living habits. In conclusion, this study for comparing and analyzing common points and differences of small-sized apartment plan compositions in Seoul and Shanghai will provide proper guidelines for small-sized apartments to be built in Seoul and Shanghai in the future, if strong points and weak points of plan compositions in the two countries will be additionally analyzed and remedied.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.2
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• pp.617-622
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• 2018

Air is essential for human beings to survive, but urban air is polluted with soot and harmful gases, due to the increase in industrial development and the population. Thus, air pollution in large cities is of increasing interest in the research community. One of the plausible solutions to this problem is supplying sufficient oxygen to indoor spaces. The main principle of the oxygen generator is to separate oxygen from air using synthetic zeolite. Various synthetic zeolites have been applied to public indoor spaces with the focus being placed on the oxygen exchange quality. Among the characteristics of zeolites which can be applied to oxygen generators is their ability to adsorb nitrogen from the air and, in this way, generate only oxygen. Thus, we investigated the degree of nitrogen adsorption by five kinds of natural zeolite and LTA zeolite 3A, 4A, and 5A (two different sizes). Using the PSA method, the higher the degree of nitrogen adsorption, the higher the oxygen saturation concentration, it was found that the nitrogen adsorption degree of the 5A zeolite was the highest. 6% on average. It was also found that the size of the zeolite had a significant effect on the degree of nitrogen adsorption.

• Journal of Yeungnam Medical Science
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• v.34 no.1
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• pp.69-74
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• 2017

Background: Chronic kidney disease is considered a risk factor for thyroid nodules as well as thyroid dysfunction such as hypothyroidism. Among patients on hemodialysis, we assessed the size of thyroid nodule and goiter at baseline and 1 year later with ultrasonography. Methods: We prospectively selected 47 patients with hemodialysis at January 2012 and reviewed their medical records. We checked goiter and thyroid nodules at January 2012 and December 2012. Results: In the hemodialysis patients (n=47), 24 patients (51.1%) had thyroid nodules and 33 patients (70.2%) had goiter at baseline. Parathyroid hormone (PTH) was higher in patients with thyroid nodules ($204.4{\pm}102.9$ vs. $129.9{\pm}93.6pg/mL$, p=0.01). Thyroid ultrasonography was conducted in 29 patients after 1 year. The thickness of the thyroid isthmus increased ($2.8{\pm}1.6$ vs. $3.2{\pm}1.9mm$, p=0.003), but the number of nodules did not change ($1.2{\pm}1.9$ vs. $1.4{\pm}2.0$, p=0.109). PTH was associated with the enlargement of thyroid nodules significantly through logistic regression analysis. Conclusion: Thyroid goiter and nodules in hemodialysis patients were more prevalent than in the general population. PTH influenced the production of thyroid nodules in hemodialysis patients. Regular examination with thyroid ultrasonography and thyroid function test should be considered in hemodialysis patients.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.32 no.3
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• pp.317-319
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• 1999

The ciliate, Vorticella was often observed in the rotifer mass culture tanks as common co-existing organism. This Vorticella performed as a predator for aquatic bacteria population in the rotifer mass culture tanks. This study was carried out to investigate a cyst formation medium of Vorticella in the laboratory for keeping Vorticella seed. The test organism Vorticella sp. was isolated from culture water of rotifer mass culture tanks. The cyst of Vorticella was formed by dried-method for the formation and maintainance of cyst. MCCF (Marine Ciliate Cyst Formation) medium was used for cyst formation (incystment), preservation and return to moving cell (excystment) of the marine ciliate, Vorticella sp. The cyst shape and size were ellipical type and $30.51 \pm1.98\;\mu$m (Avg. $\pm$ SD) of minor axis and $28.89 \pm2.12\;\mu$m (Avg. $\pm$ SD) of minor axis (n=10), The Vorticella cyst was kept in the room temperature ($10\~35^{\circ}C$) and total dark condition (24D:0L) during 1 year. The preserved cyst was transferred to moving cell state (excystment) only by the addition of fresh sea water in the MCCF medium. The five Vorticella sp. moving cells of excysted from cysts showed the growth up to 912$\pm$64 cells/10 ml in MCCF medium during the culture period of 16 days. This MCCF medium was very useful tool for cyst formation and species preservation of marine ciliate Vorticella.