• The Journal of Engineering Geology
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• v.23 no.2
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• pp.95-104
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• 2013

This study proposes an efficient management plan for improving the water quality of agricultural reservoirs. Hongdong reservoir is located in an area that includes farmland, forest, residential housing, and livestock farms. The levels of pollutants in Hongdong reservoir were investigated with the aim of improving the water quality in the reservoir. The potential concentrations of total nitrogen (T-N) and total phosphorus (T-P) in Hongdong reservoir were 1.06-3.67 and 0.52-1.12 $g/m^2-d$, respectively. An analysis of leaching characteristics was performed under anaerobic conditions for 72 hours at $20^{\circ}C$. The concentrations of T-P and $PO_4$-P were measured by general leaching for a set period. In the case of T-P, the leaching was measured by irregular leaching due to denitrification of nitrite nitrogen ($NO_2$-N) and nitrate nitrogen ($NO_3$-N). A very small amount of $NH_3$-N on nitrogen ($N_2$) was measured due to the low pH in the column, as a consequence of the anaerobic conditions.

• Journal of Soil and Groundwater Environment
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• v.10 no.5
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• pp.37-44
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• 2005

The main object of this study is to develop the infiltration facility that it can be used in grounds, parking areas, roads, pathway, housing etc. As a result, it is much alike in the infiltration method of facility to use permeable concrete, permeable hole and be filled with broken stones. And through this experiment, it was perceived the truth that the state of ground, the groundwater level, buildings around them, the history of submerging and the applicable infiltration facilities are the key. To verify how much the infiltration facility reduce the outflow, we set up the infiltration facility in the test area. In result, it reduced the outflow 89% in 24 mm rainfall, 93% in 12 mm, 51% in 140 mm, 75% in 64 mm and 80% in 54 mm. As the rainfall rate increased, the infiltration increased up to the limited rainfall. And in the limited rainfall, we knew that the infiltration was reduced suddenly. Infiltration is closely related to the state of ground, the rain interval etc. and we will analyze these conditions through the continuous monitoring.

• Environmental Analysis Health and Toxicology
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• v.27
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• pp.13.1-13.10
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• 2012

Objectives: We aimed to investigate the acute effects of heat stress on body temperature and blood pressure of elderly individuals living in poor housing conditions. Methods: Repeated measurements of the indoor temperature, relative humidity, body temperature, and blood pressure were conducted for 20 elderly individuals living in low-cost dosshouses in Seoul during hot summer days in 2010. Changes in the body temperature, systolic blood pressure (SBP) and diastolic blood pressure (DBP) according to variations in the indoor and outdoor temperature and humidity were analyzed using a repeated-measures ANOVA controlling for age, sex, alcohol, and smoking. Results: Average indoor and outdoor temperatures were $31.47^{\circ}C$ (standard deviation [SD], $0.97^{\circ}C$) and $28.15^{\circ}C$ (SD, $2.03^{\circ}C$), respectively. Body temperature increased by $0.21^{\circ}C$ (95% confidence interval [CI], 0.16 to $0.26^{\circ}C$) and $0.07^{\circ}C$ (95% CI, 0.04 to $0.10^{\circ}C$) with an increase in the indoor and outdoor temperature of $1^{\circ}C$. DBP decreased by 2.05 mmHg (95% CI, 0.05 to 4.05 mmHg), showing a statistical significance, as the indoor temperature increased by $1^{\circ}C$, while it increased by 0.20 mmHg (95% CI, -0.83 to 1.22 mmHg) as outdoor temperature increased by $1^{\circ}C$. SBP decreased by 1.75 mmHg (95% CI, -1.11 to 4.61 mmHg) and 0.35 mmHg (95% CI, -1.04 to 1.73 mmHg), as the indoor and outdoor temperature increased by $1^{\circ}C$, respectively. The effects of relative humidity on SBP and DBP were not statistically significant for both indoor and outdoor. Conclusions: The poor and elderly are directly exposed to heat waves, while their vital signs respond sensitively to increase in temperature. Careful adaptation strategies to climate change considering socioeconomic status are therefore necessary.

• Journal of Environmental Policy
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• v.10 no.4
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• pp.39-59
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• 2011

In this article, I would like to analyze the conditions in applying the LCC method for each construction type by selecting 10 apartment complexes among the Turn-key projects which have been ongoing for the last 5 years. In addition, this article will identify the problems to the application of double landscape architecture and suggest improvement measures. Among the 10 case targets, a total of 151 LCC analyses were conducted, and the average application ratio placing for each construction type was shown in the following order: architecture (34.4%)> electricity (21.2%)>machine (18.5%)>civil engineering (13.2%)>landscape architecture (12.6%). As numbers show, landscape architecture was the lowest. The ratio of LCC reduction amount was shown in the following order: machine (32.1%)> architecture (23.9%)>electricity (23.4%)>civil engineering (17.5%)>landscape architecture (3.1%). The field of landscape architecture had a reduction amount that was about 5 to 6 times lower than civil engineering which had a similar number of LCC analysis cases. The total LCC analysis items of landscape architecture was 19, including 15 double packing material, 1 building covering, 1 grass planting, 1 planting infrastructure, and 1 facility. The following measures were suggested to promote LCC analysis in landscape architecture: first, set an analysis item that considers the construction expense ratio of landscape architecture; second, legal regulation of landscape architecture and expansion of its application; third, prepare VE/LCC standards which are suitable for landscape architecture.

• Environmental and Resource Economics Review
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• v.21 no.3
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• pp.743-776
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• 2012

This study utilizes the meta-analysis for the benefits transfer (MA-BT) approach to measure social costs the 7 target sites in the City and County of Honolulu. The estimated MA models (MA-1 and MA-1) were evaluated in terms of validity and reliability criteria. This study utilized a parametric t-test and a non-parametric sign rank test for checking validity. A transfer error measured by an absolute percentage difference was utilized to check reliability their similarity. The GIS was utilized for data collection in order to measure social costs for each target site. The results clearly demonstrated that social costs were substantially higher thant direct costs and varied market conditions and different methods used. In terms of validity and reliability criteria, MA models were preferred to the mean transfer value approach. MA-BT approach is desirable for measuring social costs for a project designed to measure social costs for these 7 proposed landfill sites with inaccessible data, on short time frames, and with little money. If researchers and planners have enough time and money, they can implement primary research. If not, the meta-analysis for the benefits transfer approach can be much better than no framework. The use of a GIS can help to identify secondary data within a specific radius of each target site.

• Journal of the Korean Wood Science and Technology
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• v.46 no.1
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• pp.10-16
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• 2018

Lindera erythrocarpa is a less utilized species in Korea although that it has straight stem and it grows up to 40 cm in diameter. A proper kiln-dry schedule is required in advance to utilize an unknown species. Terazwa's quick oven-dry method was used to find it and which was confirmed by drying 25 mm thick boards in a kiln. The average green moisture content and the average green specific gravity of Lindera erythrocarpa are 72.3% and 0.53, respectively. Prospective kiln-drying conditions obtained by Terazwa's quick oven-dry method are a initial dry-bulb temperature of $50^{\circ}C$, a initial wet-bulb depression of $4^{\circ}C$ and a final dry-bulb temperature of $75^{\circ}C$, which are in a good agreement with USDA FPL kiln-dry schedule of T5-D4. 25 mm thick boards dried in a kiln with T5-D4 kiln-dry schedule did not have any severe drying defects such as honycombing and warping. A severer kiln-dry schedule of T8-C5 was developed and applied to another kiln-drying run to confirm it.

• Journal of the Korean Association of Geographic Information Studies
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• v.22 no.4
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• pp.72-85
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• 2019

The goal of this study is to predict sexual violence crimes, which is an routine risk. The study used to the Weight of Evidence on sexual violence crimes that occurred in partly Cheongju-si for five years from 2011 to 2015. The results are as follows. First, application and analysis of the Weight of Evidence that considers the weight of evidence characteristics showed 8 out of total 26 evidences that are used for a sexual violence crimes risk prediction. The evidences were residential area, date of use permission for building, individual housing price, floor area ratio, number of basement floor, lot area, security light and recreational facility; which satisfied credibility in the process of calculating weight. Second, The weight calculated 8 evidences were combined to create the prediction map in the end. The map showed that 16.5% of sexual violence crimes probability occurs in 0.3㎢, which is 3.3% of the map. The area of probability of 34.5% is 1.8㎢, which is 19.0% of the map and the area of probability of 75.5% is 2.0㎢, which is 20.7% of the map. This study derived the probability of occurrence of sexual violence crime risk and environmental factors or conditions that could reduce it. Such results could be used as basic data for devising preemptive measures to minimize sexual violence, such as police activities to prevent crimes.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.10
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• pp.174-180
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• 2020

This paper presents the development of a tacho generator that is applicable to a DC motor for anti-aircraft weapon systems. In general, devices such as tacho generators and resolvers are used as feedback devices for controlling DC motors. A tacho generator with a wide operating temperature range was developed, which has robust characteristics against shock loads and vibrations according to the operational characteristics of anti-aircraft weapon systems. The target specifications were set based on the requirements of the tacho generator currently in operation. A rotor coupled to the shaft of the motor and a stator coupled to the housing of the motor were then designed and manufactured. The inductance was 31.0 mH, the terminal resistance was 147.7 ohms, and the rotational measurement factor was satisfactory under both normal operation and operating conditions after the maximum speed for the standard of 9.500 ± 0.475 V/krpm. In addition, the environmental suitability of the applied equipment was confirmed through the rate of change in unit temperature, and it was found that the temperature characteristics were all within 0.03 %/℃.

• Journal of the Korean Recycled Construction Resources Institute
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• v.4 no.4
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• pp.379-387
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• 2016

In this study, a survey was conducted on the required measurement and waterproofing performance for residential building underground structure leakage prevention system. According to the results of the survey, it has been determined that leakage problem is considered to be quite severe, and many respondents have agreed. The legal guidelines and regulation systems do not reflect properly on the environmental requirements or conditions, resulting in continued leakage problem. In regards to this, a standardized waterproofing technique that can be used in underground areas of residential structures is required as an obligation and the development of high performance waterproofing method that allows for wet concrete surface adhesion and a guideline, design and maintenance method that allows the control of overall situational control of leakage is required.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.38 no.11
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• pp.951-956
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• 2014

Steady-state thermal analysis was performed on a thermal equivalent circuit to determine the heat generation during operation of an interior permanent magnet synchronous motor (IPMSM). New machines must be compact and light and produce high torque density under extreme environmental conditions. Thermal analysis of an IPMSM is particularly important because excessive heat generated from the core and magnet reduces the IPMSM's output and has adverse effects on the durability. Therefore, steady-state thermal analysis of an IPMSM was performed for changes in the design variables using a thermal equivalent circuit. The changed variables were the axis length and thickness of the housing. The results of this method were compared with those of the finite element method to verify the accuracy and reliability.