• Journal of the Korean Solar Energy Society
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• v.24 no.4
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• pp.45-53
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• 2004

In the summer, the irradiated solar heat gain through the roof has an effect on the thermal environment of the top floor units of apartment houses. This paper investigated the differences of the indoor air temperature and thermal comfort index between the top floor unit and the middle floor unit by measuring them at the sample houses. The purpose of this paper is to provide quantitative data about the irradiated solar heat gain during the summertime through the roof of an apartment house and these data to be the source to reevaluate the appropriate roof insulation efficiency. From this study, we obtained the brief results as follows. Indoor air temperature at the top floor unit is $1.2\sim2.2^{\circ}C$ higher than that of middle floor unit. The evaluation of the indoor thermal comfort index at each sample rooms reveals notable thermal differences between the two units. Top floor units need more cooling load during the summertime compared to middle floor units. Therefore, solutions to reduce solar Heat gain at top floor units to be considered.

• Journal of the Korean BIBLIA Society for library and Information Science
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• v.33 no.4
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• pp.27-47
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• 2022

The purpose of the study is to develop a unit catalog system that can be linked with the curriculum. As for the research method, first, unit subject words were extracted through the analysis of middle school curriculum and science textbooks in all grades. Based on this, we designed a unit catalog system that has a unit book catalog by connecting books related to the unit topic of the subject, an index word catalog that organizes unit subject words into index words, and a grade and school level linked subject linked to the unit topic as a subsystem. Using the Notion program, a unit catalog system was implemented on the web using a middle school science unit 1 as a sample. To evaluate the system, experiments and surveys were conducted targeting students, and very positive results were shown in terms of satisfaction with the system and intention to use it in the future. Meanwhile, this study was limited to middle school science departments, but it was proposed to expand the application to all grades and subjects.

• Water for future
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• v.13 no.2
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• pp.35-47
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• 1980

An algorithm is developed to derive a representative I hr-unit hydrograph through an analysis of rainfall-runoff relations of a watershed as a closed system. For the base flow seperation of a flood hydrograph the multi-deflection method is proposed herein, which gace better results compared with those by the existing empirical methods. A modified $\Phi$index method is also proposed in this stidy to determine the time distribution rainfall excess of a rainstorm, which is essetially a modification of the commonly used $\Phi$index method of rainfall seperation. With the so-obtained rainfall excess hyetograph and the direct runoff hydrograph a trial and error computation of the ordinates of 1 hr-unit hydrograph was executed in such a manner that the synthesized flood hydrograph closely approximates the observed one, thus resulting a unit hydrograph of a piecewise exponential function type. To verify the validity of this study the 1 hr-unit hydrographs for the Imha and Dongchon in Nagdong River basin, and Yongdam in Geum River basin were derived by this algorithm, and the results were compared with those by the conventional synthetic unit hydrograph method and the Nakayasu method. Besides, the validity of this stiudy was also tested by comparing the observed hydrograph with the one computed by applying the unit hydrograph to a specific rainfall event. To generalize the result of this study a computer program, consisited of a main and three subprograns (for rainfall excess estimation, convolution summation, and sorting), is developed as a package, which is believed to be applicable to other watersheds for the similar purpose as those in this study.

• Journal of the Korean Association of Geographic Information Studies
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• v.9 no.2
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• pp.227-238
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• 2006

Line density index(LDI) was developed to quantify a densely isothermal line rate as standard index in the ocean environment. Theoretical background on the LDI development process restricting index range 0 to 100 was described. And validation test was done for the LDI application condition that total line length is not greater than 1/10 of unit area. NOAA SST(Sea Surface Temperature) data were used for the experimental application of LDI in the South Sea of Korea. Using GIS, $0.1^{\circ}C$ isothermal lines were linearized as vector data form SST raster data, and unit area were built as polygon data. For the LDI calculation, spatial overlapping(line in polygon) was implemented. To analyze the effect of unit area size for the LDI distribution, two cases of unit area size were designed and descriptive statistics was calculated including performing normality test. The results showed no change of LDI's essential characteristics such as mean and normality except for the range of value, variance and standard deviation. Accordingly, it was found that complex structure of thermal front and even smaller scale of front width than unit area size could influence on the LDI distribution. Also, correlation analysis performed between LDI and difference of temperature(${\Delta}T^{\circ}C$), and horizontal thermal gradient(${\Delta}T^{\circ}C/km$) on the front was obtained from linear regression model. This obtained value was compared with the results from previous researches. Newly developed LDI can be used to compare the thermal front regions changing spatio-temporally in the ocean environment using absolute index value. It is considered to be significant to analyze the relationship between thermal front and marine environment or front and marine organisms in a quantitative approach described in this study.

• Advances in environmental research
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• v.1 no.4
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• pp.277-288
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• 2012

This study investigated exposure to air pollutants in rooms in low-income houses at Shomolu (R1), Mafoluku (R2) and Mushin (R3) in Lagos state. The concentrations of most measured exceeded limits of Illinois Department of Public Health (IDPH) for indoor air quality. Air quality index (AQI) in rooms studied was unhealthy for sensitive people in terms of CO, unhealthy in terms of $SO_2$ and very unhealthy in terms of $NO_2$ while moderate air quality was obtained in terms of $PM_{10}$ in most rooms. High concentrations of carbontetrachloride, formaldehyde and xylene measured could have been responsible for some of the health complaints of the occupants. Factor analysis shows that cooking with kerosene, use of gasoline generator and insecticide were the major contributors to indoor air pollution in these rooms. Therefore, there is need to urgently tackle poverty as all affected by these pollutants were poor who live in substandard houses without kitchens.

• Journal of Korean Society of Rural Planning
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• v.29 no.3
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• pp.15-24
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• 2023

The sense of crisis regarding regional extinction due to low birth rates and an aging population is expanding. Generally, the local extinction index is used to analyze local extinction. However, it is challenging to diagnose the actual situation of village extinction risk in rural areas, even though the regional extinction index can be analyzed in units such as Si-Gun-Gu and Eup-Myeon-Dong. This difficulty arises because the regional extinction index solely relies on natural population growth indicators (elderly population and female population aged 20-39). Therefore, the purpose of this study is to develop a village extinction index that can identify the disappearance of rural villages. Additionally, the aim is to apply the developed indicators to the village (administrative ri) spatial unit. The existing regional extinction index used only mortality-related indicators as factors for natural population decline and fertility-related indicators as factors for natural population growth. However, the developed village extinction index included not only the factors of natural population change but also incorporated social population growth factors and factors related to the pace of village extinction. This is the key difference between the developed village extinction index and the existing regional extinction index. In this study, the indicators of "total population," "number of young women aged 20-44," "number of elderly population aged 70 or older," and "number of incoming population" were selected to develop a village extinction index. The village extinction index was developed by incorporating both natural population growth indicators and social population growth indicators. The developed village extinction index was applied to administrative villages. This research is expected to provide a more accurate understanding of the current state of rural villages facing extinction.

• Journal of Preventive Medicine and Public Health
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• v.46 no.5
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• pp.226-236
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• 2013

Objectives: The aim of this study was to examine the levels of serum 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) and evaluate their association with age, body mass index, smoking, military record-based variables, and estimated exposure to Agent Orange in Korean Vietnam veterans. Methods: Serum levels of TCDD were analyzed in 102 Vietnam veterans. Information on age, body mass index, and smoking status were obtained from a self-reported questionnaire. The perceived exposure was assessed by a 6-item questionnaire. Two proximitybased exposures were constructed by division/brigade level and battalion/company level unit information using the Stellman exposure opportunity index model. Results: The mean and median of serum TCDD levels was 1.2 parts per trillion (ppt) and 0.9 ppt, respectively. Only 2 Vietnam veterans had elevated levels of TCDD (>10 ppt). The levels of TCDD did not tend to increase with the likelihood of exposure to Agent Orange, as estimated from either proximity-based exposure or perceived self-reported exposure. The serum TCDD levels were not significantly different according to military unit, year of first deployment, duration of deployment, military rank, age, body mass index, and smoking status. Conclusions: The average serum TCDD levels in the Korean Vietnam veterans were lower than those reported for other occupationally or environmentally exposed groups and US Vietnam veterans, and their use as an objective marker of Agent Orange exposure may have some limitations. The unit of deployment, duration of deployment, year of first deployment, military rank, perceived self-reported exposure, and proximity-based exposure to Agent Orange were not associated with TCDD levels in Korean Vietnam veterans. Age, body mass index and smoking also were not associated with TCDD levels.

• Journal of Positioning, Navigation, and Timing
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• v.6 no.3
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• pp.117-123
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• 2017

In this paper, we propose a performance index that can compare the position estimation performance according to the time slot allocation order, which is superior in the position estimation performance in the operation of the Link-16 based relative navigation system. In order to verify the validity of the performance index, a software-based Link-16 relative navigation system performance analysis platform composed of a signal generator, a signal reception and navigation algorithm execution unit, and a performance analysis unit was designed. Using the designed software platform, we analyzed the relationship between proposed performance index and position estimation performance according to time slot allocation order in the same position reference (PR) arrangement. The performance index of the proposed time slot allocation is expected to be utilized not only for the Link-16 system, but also for the Time Division Multiple Access (TDMA)-based navigation system.

• Journal of Korean Society of Rural Planning
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• v.27 no.1
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• pp.103-116
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• 2021

The purpose of this study is to analyze and diagnose the actual state of extinction risk in rural villages by analyzing time series population characteristics and extinction risk index of rural villages(Haengjeong-ri). As a research method, a time series analysis was performed on the 'population over 65' and the 'female population aged 20 to 39' related to the local extinction index. In addition, the disappearance of Haengjeong-ri village was analyzed using the existing local extinction index. For the study, Haengjeong-ri village-level GIS spatial data was constructed, and population attribute data in 2010, 2015, and 2020 were constructed. In order to derive implications, the change of the 'high risk of extinction 'village in the 2020 local extinction index, the distribution of the population of 'high risk of extinction' villages by three years, the population analysis of 'high risk of extinction' villages continuously from 2010 to 2020, and 'high risk of extinction' An analysis of the increase and decrease of the population of the village and the change of the local extinction index of Haengjeong-ri, where the city, county, and towns are located were analyzed. As a result of the analysis of this study, it was found that the number of villages with an aging of more than 50% increased by 2 to 3 times over 10 years. As a result of the analysis of the local extinction index, in 2010, the southwestern and central regions of South Chungcheongnam-do were high-risk extinction areas, but in 2020, all cities except Cheonan and Asan were converted to high risk extinction areas. Research has shown that Chungnam is facing a serious aging and village extinction crisis, and since the disappearance of villages gradually spreads, an initial response policy is needed. This result will be the same not only in Chungcheongnam-do but also in other rural villages. Therefore, in the case of rural villages, it is necessary to analyze and diagnose the Haengjeong-ri village unit, not the Eup-Myeon unit, and a response policy through diagnosis must be prepared urgently.

• Food Science and Preservation
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• v.12 no.1
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• pp.23-27
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• 2005

Yolk index (In, Haugh unit (BU) and weight loss of quail egg were measured to evaluate the effect of composite film (SPI/corn starch). Also, the effect of composite film was investigated to extend the shelf-life of sandwich foods. The quality characteristics of sandwich food was measured by the weight increment The weight reduction ratio for quail egg coated with composite film showed $8\%$ increment after 20 day storage. Yolk index and Haugh unit were significantly different between the uncoated and coated quail eggs with composite film solution. Sandwich coated with composite film showed the less weight increase for 12 hour storage compared to controls.