• Journal of the Korean Solar Energy Society
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• v.36 no.6
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• pp.25-35
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• 2016

In this study, the evaluation of the dynamic behavior and thermal performance of the "Façade integrated Natural circulation Solar Water Heating System" installed in the residential house was carried out. Experimental tests were performed during the all year around in the rural houses of $166m^2$ in size. Facade integrated solar collector of $5m^2$ were installed on the south-facing. Electrical heater of 1 kW capacity as an auxiliary heater was installed at the upper part of the heat storage tank. The analyzing results are as follows. (1) Monthly average solar fraction was 51 to 87% and yearly average value is 64%. (2) Hot water supply temperature in December which has the lowest solar altitude is 37 to $76^{\circ}C$. The highest working fluid temperature of solar collector in this period was below $84^{\circ}C$. The temperature difference of working fluid between the collector inlet and outlet has been shown to be around 9 to $26^{\circ}C$. (3) Overheating which is one of the biggest problems during summer did not appear at all, but rather had hot water supply temperature is rather low as $30{\sim}47^{\circ}C$ in summer than winter, which is supplied by a small solar load. The solar collecting temperature has been shown to maintain below $55^{\circ}C$. (5) The thermal performance of Facade integrated solar collector can be increase due to the reduction of heat loss to the back of the collector wall integration of the collector is reduced. As a conclusion, Facade integrated natural circulation type Solar Water Heating System is a well-functioning without any pumps or controllers, and it was found that the disadvantages of conventional solar water heaters, hot water or hot water system can be greatly improved.

• Korean Journal of Plant Resources
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• v.30 no.2
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• pp.176-190
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• 2017

South Korea is the northernmost distributional territory on the Camellietea japonicae (evergreen broad-leaved forests of the warm-temperate zone) in East Asia. A total of 40 stands were collected in terms of an ecologically-naturalized wild tea population (WTP), and their species composition was analyzed by $Z{\ddot{u}}rich$-Montpellier School's method with preliminary regard to forest canopy idendtification. Stand types were characterized by ecological flora's criteria such as Raunkiaer's life-form, neophyte, zonal distribution, and nativeness of species. Expansion of WTP distribution into the interior of the peninsula was recognized, than expected. The highest and northernmost WTPs have been recorded at Mt. Palgong, Daegu (390 m a.s.l.) and Iksan Jeonbuk (latitude $36^{\circ}$ 03' 33''), respectively. Altitudinal and latitudinal WTP distribution of Korea under continental climate shows lower than Japanese situation under oceanic climate. Community structure generally involved a few human interferences. Syngeographically WTP distribution was limited on the warm-temperate zone and the southernmost cool-temperate southern submontane zone. First driving force on distributional expansion of the WTP was anthropogenic, particularly in the northernmost distribution area. We finally confirmed an actual existence of the WTP in South Korea and suggested a long-term monitoring on the WTPs in national view of in-situ genetic resources with higher frost-resistance.

• Korean Journal of Plant Resources
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• v.30 no.2
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• pp.167-175
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• 2017

We conducted a total of 28 surveys from March to October 2016 in Gayasan National Park, to identify threatened plants for climate change, as well as for the effective management of biological organisms and resources against climate changes in Korea. Regarding threatened plants for climate change, we identified a total of 39 taxa, with 11 northern, 2 southern, and 26 taxa of concern. Among these taxa, 33 were identified as wild species. The species threatened by climate change located in the subalpine regions of Gayasan National Park were Abies holophylla Maxim., Abies koreana Wilson, Pinus koraiensis Siebold & Zucc., Betula ermanii Cham., Berberis amurensis Rupr., Rhododendron tschonoskii Maxim., Vaccinium hirtum var. koreanum (Nakai) Kitam., Primula modesta var. hannasanensis T.Yamaz., Trientalis europaea var. arctica (Fisch.) Ledeb., Thymus quinquecostatus Celak., Parasenecio firmus (Kom.) Y.L.Chen, and Lilium cernuum Kom. These species are expected to be particularly vulnerable to the effects of global warming, since they were confirmed to have a very narrow vertical distribution range. Moreover, although the following species are not included in the list of plants threatened by climate change, it is assumed that the endemic species that grow at the summit, and Grade V floristics special plants, such as Pedicularis hallaisanensis Hurus., Allium thunbergii var. deltoides (S.O.Yu, S.Lee & W.Lee) H.J.Choi & B.U.Oh, Heloniopsis tubiflora Fuse, N.S.Lee & M.N. Tamura, Aletris glabra Bureau & Franch, and Gymnadenia cucullata (L.) Rich., will also be extremely vulnerable to climate change. Therefore, we believe that measures for the conservation of these species are urgently needed, and also that the definition of species threatened by climate change should be broadened to include more objective and valid taxa through the long-term monitoring of species distributed around the summit area.

• Korean Journal of Plant Resources
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• v.30 no.2
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• pp.219-239
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• 2017

This study was carried out to investigate the vascular plants of the protected area for forest genetic resource conservation in the National Yonghyeon natural recreation forest. The vascular plants collected 7 times (from February to September 2014) were consist of total 460 taxa; 95 families, 280 genera, 398 species, 3 subspecies, 50 varieties and 9 forms respectively. The 6 taxa of Korean endemic plants and 8 taxa of Korean rare plants were investigated. The floristic regional indicator plants found in this area were 43 taxa comprising 7 taxa of grade IV, 7 taxa of grade III, 12 taxa of grade II, 17 taxa of grade I. The naturalized plants were 39 taxa, therefore naturalized ratio was 8.5%. 460 taxa listed consist of 189 taxa (41.1%) of edible plants, 155 taxa (33.7%)of medicinal plants, 177 taxa (38.5%) of pasture plants, 52 taxa (11.3%) of ornamental plants, 17 taxa (3.7%)of timber plants, 12 taxa (2.6%) of fiber plants and 3 taxa (0.7%) of industrial plants. The vegetation status of investigated area was comparatively well conserved, but human-induced damage is increasingly greater. Therefore, a long-term monitoring of vascular plants and vegetation movement must become accomplished.

• Korean Journal of Veterinary Service
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• v.41 no.3
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• pp.157-163
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• 2018

In order for monitoring of pathogenic bacterial contamination in the freshly slaughtered poultry meats produced in Gyeong-Nam province, we first isolated 4 strains of Salmonella spp. and 32 strains of Enterococcus faecalis from the total 164 samples, then we analyzed potential virulence gene profiles of the bacterial isolates by PCR using species-specific primer. The potential virulence genes we selected in this study were stn, invA, fimA, spvR, and spvC for the isolates of Salmonella spp. and those of esp, cylM, cylA, cylB, gelE, fsrA, fsrB, and fsrC were for the isolates of E. faecalis. The PCR results showed that all 5 virulence genes were detected simultaneously in the all isolates of Salmonella spp. However, there was a diverse occurrence pattern of the virulence genes in the case of E. faecalis. The gene for enterococcal surface protein (esp) was not detected among the isolates (0/32), and the haemolysin gene prevalence rate of cylA, cylB, and cylM were 3.1% (1/32), 9.3% (3/32), and 9.3% (3/32), respectively. Moreover, the genes of gelE, fsrA, fsrB, and fsrC that associated with gelatinase activity were detected in the rate of 53.1% (17/32), 53.1% (17/32), 53.1% (17/32), and 53.1% (17/32), respectively. In conclusion, in the isolates of Salmonella spp., all possessed 5 virulence genes tested, suggesting that they are all related with each other clonally. However, in the case of E. faecalis isolates, the occurrence of the haemolysin genes (cylM, cylA, cylB) and the gelatinase genes (gelE, fsrABC) was highly variable among the isolates.

• Journal of Environmental Health Sciences
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• v.41 no.5
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• pp.349-357
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• 2015

Objectives: The 2007 Korea National Survey for Environmental Pollutants in the Human Body found the highest blood mercury levels nationwide among residents in Seoksan-ri, Goro-myeon, Gunwi-gun, Gyeonsangbuk-do. With the aim to reduce the blood mercury levels of residents in this region, we conducted this study to identify the association between mercury exposure levels and shark meat consumption. Methods: This survey was conducted with 118 participants in Seoksan-ri before the Chuseok festival and 113 residents were added afterwards. Information on participants was collected via questionnaires. Total mercury concentrations in biological samples were measured using a mercury analyzer with the gold-amalgam collection method. Results: To identify this, we conducted mercury exposure level analysis before and after the Chuseok festival and found that blood and urinary mercury levels after Chuseok (GM of $6.9{\mu}g/L$ in blood and $1.68{\mu}g/g$_cr in urine) were higher than those before (GM of $5.29{\mu}g/L$ in blood and $1.44{\mu}g/g$_cr in urine). This area maintains a custom of using shark meat as one of the ancestral rite foods, and the performance of such rites and shark meat consumption have been identified as main sources of mercury exposure. Other than this, smoking, dental amalgam treatment and residential period in the area also contributed to an increase in mercury exposure levels. On the other hand, recent consumption of oriental medicine and vaccination did not have a significant influence on mercury levels. Conclusion: The results were attributed to the local custom of consuming shark meat with high mercury concentrations during rituals taking place during the festival and ancestral rites. Given that the blood mercury levels in 23.2% of the residents exceeded the HBM II values recommended by the German Commission on Human Biological Monitoring, it is suggested that further appropriate actions and follow-up measures be taken to reduce the mercury exposure levels of the residents that exceeded the reference values.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.27 no.11
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• pp.581-586
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• 2015

In this study, an analysis was performed on the performance of the solar water heating system with geo-thermal heat pump for a detached house. This system has a flat plate solar collector ($8\;m^2$) and a 3 RT heat pump. The heat pump acts as an auxiliary heater of the solar water heating system. These systems were installed at four individual houses with the same area of $100\;m^2$. The monitoring results for one year are as follows. (1) The average daily operating time of the solar system appeared to be 313 minutes in spring (intermediate season), and 135 minutes and 76 minutes in winter and summer respectively. The reason for the short operating time in summer is the high storage temperature due to low water heating load. The high storage temperature is caused by a decrease in collecting efficiency as well as by overheating. (2) The geothermal heat pump as an auxiliary heater mainly operates on days of poor insolation during the winter season. (3) Despite controlling for total house area, hot water consumption varies greatly according to the number of people in the family, hot water usage habits, etc. (4) The yearly solar fraction was 69.8 to 91.5 percent, which exceeds the maximum value of 80% as recommended by ASHRAE. So the solar collector area of $8\;m^2$ appeared to be somewhat greater for the house with an area of $100\;m^2$. (5) The observed annual efficiency of solar systems was relatively low at 13.5 to 23.6%, which was analyzed to be due to the decrease in thermal efficiency and the overheating caused by a high solar fraction.

• Korean Journal of Environment and Ecology
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• v.30 no.3
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• pp.320-327
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• 2016

Intertidal zone has been restored by the Sihwa Lake tidal power plant is operating in 2012. After restoration, to check the difference of bird group's community change out, the examination has been carried out from 2009 to 2014 when sea dike sluicer runs, the intertidal zone area was increased to $20.3km^2$ after restoring in $5.3km^2$. There was no significant difference in the number of individuals congestion of the whole, but the results of analysis of the differences between the six bird group by number of individuals, it showed a significant difference in Diving ducks(p = 0.237) the Herons (p<0.001), Swans and Geese (p<0.01), Dabbling ducks (p<0.001), showed a significant difference in the Shore birds (p<0.001) gulls (p<0.001) except for diving of ducks. Sihwa Lake intertidal zone was only just been restored, but environment and the improvement of benthic ecosystem has been carried out, It is determined that waterfowls that living based on intertidal zone are also affected. This study is a good example of the restoration of the intertidal zone that disappeared, which hard to find a similar case. It will be utilized as basic data of ecological monitoring for the conservation and management of the future of the intertidal zone later.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.6
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• pp.1-8
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• 2016

Current sensors are used widely in the fields of current control, monitoring, and measuring. They have become more popular with the increasing demand for smart grids in a power network, generation of renewable energy, electric cars, and hybrid cars. Although open loop Hall effect current sensors have merits, such as low cost, small size, and weight, they have low accuracy. This paper describes the design and fabrication of a 300A open loop current sensor that has high accuracy and temperature performance. The core of the current sensor was calculated numerically and the signal conditioning circuits were designed using circuit analysis software. The characteristics of the manufactured open loop current sensor of 300 A class was measured at currents up to 300 A. According to the test of the current sensor, the accuracy error and linearity error were 0.75% and 0.19%, respectively. When the temperature compensation was carried out with the relevant circuit, the temperature coefficients were less than $0.012%/^{\circ}C$ at temperatures between $-25^{\circ}C$ and $85^{\circ}C$.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.6
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• pp.129-139
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• 2016

The purpose of this paper was to comparatively investigate the efficient building incentives in Korea and foreign countries and to seek strategies to enhance low energy building integrated design market infrastructure in Korea. The structure of incentive policies were composed of four main component: 1) types of financial aids and beneficiaries, 2) energy performance criteria and verification methods, 3) supports for low energy building integrated design, and 4) funding sources for incentive programs. Every overseas incentive program has adopted a design team incentive along with building owners incentive and the range of target buildings have been extended from new construction to remodeling projects. The main system of the program is the performance standard through which projects were investigated and the level of incentive are decided. Initially, the integrated performance has been investigated through simulation methods, but the construction performance evaluation and energy monitoring methods are emerging. In addition, the direct support and educational support for integrated design has been provided to enhance the foundation of relative markets. Financial funding is also a key component of the program and more aggressive funding strategies have been adopted.