• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.22 no.3
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• pp.77-87
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• 2017

Picophytoplankton, an important primary producer especially at the oligotrophic region, is known to contribute a significant portion of the total phytoplankton biomass in the East Sea of Korea. During autumn in the southwestern East Sea, frequent upwellings and oligotrophic conditions occur and annual variation of primary productivity is known to be significant. Moreover sea surface temperature (SST) of the East Sea is steeply increasing compared to global average increase, so various changes in marine ecosystem related with increase of SST are reported. Taking such circumstances into consideration, we measured the contribution from picophytoplankton fraction to total phytoplankton composition by size fraction of phytoplankton biomass during the autumn seasons from 2011, 2013 and 2015 and examined the variation of the phytoplankton composition. As a result of size fraction analyses, we found that the variation of contribution from picophytoplankton(<$3{\mu}m$) to total community of phytoplankton was high and the average fractions of picophytoplankton were measured as 38% (2011), 59% (2013), 7% (2015), respectively. The difference between measured SST and annual mean SST (${\Delta}T$) was highest ($+1.6^{\circ}C$) in autumn of 2013 and lowest ($-0.9^{\circ}C$) in autumn of 2015. The close positive correlation between ${\Delta}SST$ and fraction of picophytoplankton was confirmed($R^2$ > 0.9). The increase in SST at the southern East Sea was confirmed as one of the main environmental factors in the increase in the increase of the contribution from picophytoplankton. Monitoring of changes in the community structure of primary producers and the influences of the environmental factors including SST in the East Sea is necessary to understand the interactions of ecosystem of the East Sea and the climate change in the near future.

• Korean Journal of Ecology and Environment
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• v.41 no.1
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• pp.54-65
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• 2008

The seasonal dynamics of phytoplankton and water quality were evaluated bimonthly at 7 park ponds in the capital region from October 2004 to August 2005. With out the change of water temperature $(0.4\sim26.0^{\circ}C)$, cyanobacteria dominated in park ponds such as Gyungbokgung Gyunghyaeru and Seokchon reservoir. The standing crops of phytoplankton was significant related with cell densities of cyanobacteria (r=0.993), while they did not significant correlation with environmental factors. Almost of all park ponds in the capital region were classified as eutrophic state with high TP concentrations and TN/TP ratios less than 10. Major dominant cyanobacteria were as followed; Anabaena sp., Aphanocapsa elachista, Lyngbya contorta, Merismopedia elegans, Microcystis aeruginosa, M. wesenbergii, Microcystis sp., Oscillatoria sp., Phormidium tenue, and Plectonema sp. To date, although the concentration of chlorophyll-${\alpha}$ and cyanobacterial densities in the capital region was below the 'danger' level of WHO guidelines value, the monitoring of cyanobacterial densities and its toxin (microcystin) in recreational/bath water should be continued.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.9
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• pp.422-430
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• 2016

We investigated the abundance and composition of the zooplankton community around Dokdo in the East Sea from 2006 to 2015. Zooplankton samples were collected in the surface mixed layer by vertical hauls using a standard type net at the monitoring stations. There were no clear long-term trends in the average temperature and salinity, but relatively low salinity was recorded in the summer of 2013 and 2015. The average abundances of zooplankton in the summer increased by two orders of magnitude from $317inds./m^3$ in 2008 to $10,242inds./m^3$ in 2015. This long-term increase was accompanied by a slight increase in the chlorophyll-a concentration and a decrease in the catch of potential crucial predators (anchovy, mackerel pike, squid, herring and horse mackerel) in the study area. The dominant zooplankton, accounting for most of the long-term increase, consisted of appendicularian (Oikopleura spp.), which showed a steady increase since 2012, summer species such as Noctiluca scintillans and the cladoceran Penilia avirostris, which showed an abrupt increase, and the copepod Paracalanus parvus s.l., which showed a rapid increase after its first occurrence in summer 2010. These results suggest that the long-term increase of zooplankton could be related to the increase in the concentration of prey and the decrease in the predation pressure of potential predators around Dokdo in the study area.

• Journal of KIISE:Computing Practices and Letters
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• v.15 no.9
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• pp.661-674
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• 2009

Recently, there has been much research and many attempts to enhance converged information technology services using new technology such as ubiquitous sensor networks (USN) in medical, environmental, industrial, and logistic areas. There has also been much research and various attempts to apply this new technology to agricultural areas. However, applications to the agricultural areas should be considered differently against the same areas such as medical, environmental, industrial, and logistics. Therefore, this paper suggests that an agricultural cultivating management and traceability system. This system is a unified system that supports the processes sowing seeds through selling agricultural products to consumers. Farmers can be provided with an effective calendar for cultivation and weather information in real time as well as the monitoring of the growth of farm products on the farm in real time using this system. Farmers can also control all equipment installed on the farm directly or remotely and the equipment can be controlled automatically when the measured values such as temperature and humidity deviate from the decent criteria which are set by farmers or this system. Additionally, the reliability for and the better quality of the agricultural products can be improved because farmers can use this unified system to cover all processes from sowing seeds to selling to consumers.

• Journal of Yeungnam Medical Science
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• v.12 no.2
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• pp.260-268
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• 1995

Ischemia results when the decrease in tissue perfusion exceeds the tissues ability to increase an oxygen extraction from the blood. Brain edema has been defined as an abnormal accumulation of fluid within brain parenchyma associated with a volumetric enlargement of the brain tissue. In most instances, the labelling of edema as vasogenic or cytotoxic is only relative. For cerebral protection, there were many possible techniques which could increase or maintain cerebral perfusion and reduce cerebral metabolic demand for oxygen. This study was carried out the effect of mild brain hypothermia which was induced by infusion with cold saline into the carotid artery, during brief episodes of transient global ischemia on postischemic brain edema in rabbit. Eight rabbits were anesthetized with halothane and mechanically ventilated with oxygen. For isolated cerebral perfusion, polyethylene catheter was inserted left carotid artery for infusion of cold saline, external carotid artery was ligated, vertebral arteries were cautherized, right carotid artery was snared for ischemia and femoral artery and vein were also canulated for monitoring and drug treatment. At 3 hours After transient global ischemia, specific gravity of cerebral cortex and hippocampus was compared with no-perfusion group , perfusion with cold saline group and normal group. There was no significant differences in physiologic variables among the groups before transient global ischemia. But during transient global ischemia, brain temperature of perfusion group was decreased when compared to no perfusion group. Specific gravity of cerebral cortex and hippocampus of no-perfusion group and perfusion group was statistically significant when compared to normal group (p<0.01). The results of this study suggested that mild brain hypothermia with intracarotid cold saline infusion during brief episodes of transient global ischemia had decreased postischemic brain edema in rabbit.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2009.10a
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• pp.1010-1013
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• 2009

The youths of the farming village have moved to the metropolis, thus the most of the manpower which engages to a production remained in the village reaches layer old age and all thing sprouts long the whole and it is one. So to remove the waste of barn rather than to give feed to the livestock is hard that what step all automation of this part is necessary. Consequently we have developed the automation system in order to reduce the massive death of the livestock at the time of intense cold and hot. The system will be able to clean the waste of the barn and confront quickly in the change of temperature which is sudden it came. And we proposed also the system that will be able to watch at real-time and monitor the operational environment from a remote using CCD camera. In this paper, we proposed the remote control system which uses PDA in order to control the automation system of a stall while moving. The proposed system was embodied in order for the control and the monitor while the user is mobile using PDA screens. We also added a protection system in that system. The system sends the case warning and SMS while will have the fire and the intrusion from the outside and prevents a robbery.

• Journal of Environmental Health Sciences
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• v.47 no.5
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• pp.472-478
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• 2021

Background: The Legionella case detection and notification rate have increased in public artificial water environments where people visit, including large buildings, public baths, and hospitals. Objectives: In this study, the distribution of Legionella and its epidemiologic characteristics were analyzed in the water systems of public facilities in Chungcheongnam-do Province in South Korea. Methods: Culture and PCR analysis were performed on 2,991 environmental water system samples collected from 2017 to 2019, and associations with year, facilities, seasons, and temperature of water system were statistically analyzed by using R-Studio for Windows. Descriptive data was compared using chi-square tests and independent t-tests. Results: The detection rate of Legionella increased from 3.1% in 2017 to 10.3% in 2019, appearing most frequently in the order of public baths, large-scale buildings, hospitals, and apartments. It was detected mainly in summer from June to August, over 1.0×10³ CFU/L on average in 133 cases (66.5%). Lots of germs were detected in bathtub water, cooling tower water, and warm water (p<0.001), and it was detected at higher rates in the cities where multipurpose facilities were concentrated than in rural areas (p=0.018). Conclusions: This study suggests that continuous monitoring and control are required for Legionella in the water system environment of high risk facilities. Moreover, these results will be helpful to prepare efficient management plans to prevent the Legionellosis that occurs in Chungcheongnam-do Province.

• Journal of Soil and Groundwater Environment
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• v.24 no.3
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• pp.24-35
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• 2019

It is known that ${\delta}^{13}C_{DIC}$ (carbon-13 isotope of dissolved inorganic carbonate (DIC) ions) of water increases when dissolved $CO_2$ degases. However, ${\delta}^{13}C_{DIC}$ could decrease when the pH of water is lower than 5.5 at the early stage of degassing. Laboratory experiments were performed to observe the changes of ${\delta}^{13}C_{DIC}$ as $CO_2$ degassed from three different artificial $CO_2$-rich waters (ACWs) in which the initial pH was 4.9, 5.4, and 6.4, respectively. The pH, alkalinity and ${\delta}^{13}C_{DIC}$ were measured until 240 hours after degassing began and those data were compared with kinetic isotope fractionation calculations. Furthermore, same experiment was conducted with the natural $CO_2$-rich water (pH 4.9) from Daepyeong, Sejong City. As a result of experiments, we could observe the decrease of DIC and increase of pH as the degassing progressed. ACW with an initial pH of 6.4, ${\delta}^{13}C_{DIC}$ kept increasing but, in cases where the initial pH was lower than 5.5, ${\delta}^{13}C_{DIC}$ decreased until 6 hours. After 6 hours ${\delta}^{13}C_{DIC}$ increased within all cases because the $CO_2$ degassing caused pH increase and subsequently the ratio of $HCO_3{^-}$ in solution. In the early stage of $CO_2$ degassing, the laboratory measurements were well matched with the calculations, but after about 48 hours, the experiment results were deviated from the calculations, probably due to the equilibrium interaction with the atmosphere and precipitation of carbonates. The result of this study may be not applicable to all natural environments because the pressure and $CO_2$ concentration in headspace of reaction vessels was not maintained constant as well as the temperature. Nevertheless, this study provides fundamental knowledge on the ${\delta}^{13}C_{DIC}$ evolution during $CO_2$ degassing, and therefore it can be utilized in the studies about carbonated water with low pH and the monitoring of geologic carbon sequestration.

• Korean Journal of Ornithology
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• v.25 no.2
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• pp.87-93
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• 2018

In order to investigate the changes in the population of Spot-billed ducks due to changes in reclaimed land, we conducted a monthly survey from January 2008 to December 2014 at the Shihwa Lake. The average number of Spot-billed ducks was 12,204 individuals. The average population was decreased. The yearly index of fluctuation (Fi) was the highest at 2.16 in 2010. TRIM(TRends and Indices for Monitoring data) showed a steep decline in winter and a moderate decrease tendency in autumn and spring. However, in the summer season, it showed an moderate increasing tendency. The main habitat were Northland reclaimed land, agricultural land and wetland area, Tando waterway, Shihwa artificial wetland in upstream. The correlation between the number of Spot-billed ducks and the temperature was negatively correlated in spring, summer, autumn. However, winter was showed positive correlation. Therefore, it affects the community of Spot-billed ducks due to environmental changes of reclaimed land. In future, effective management is needed to prepare alternative habitat based on basic data like this study for the conservation and management of Spot-billed ducks during reclamation construction.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.19 no.1
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• pp.203-209
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• 2019

In this work, a new land-specific resistance measuring device (GM) and a measuring probe (Grounding Rod) are connected to the WENNER quadrant as power-line communication (PLC). In groups of two (P1,P2) probes, five to ten probes are installed in series on the ground at intervals of 1m, 2m, 4m, 8m, and 16m, respectively. If the PLC signal from the GMD is detected by the receiver of the Probe 1 (P1) for measurement, the minute voltage and current for measurement flow from the PSD (power supply) attached to the probe to the ground, and then, through the soil between P1 and P2, enters the Probe 1 (P2). The resistance value is then measured by the principle of voltage drop due to ground resistance. Measure the earth resistance every T seconds up to 1 trillion and store the measured data on the Arduino Server mounted on the main equipment. Stored measurement data can be derived from formulas by Ohm's Law and from inherent resistance (here,). Data obtained in real time will be linked to CDGES programs installed on Main PC, enabling data analysis and real-time monitoring of the ground environment on land. In addition, a three-dimensional display is possible with 3D graph support by identifying seasonal characteristics such as temperature and humidity of land (soils). The limitations of the study will require specific application measures of Test Bed for commercial access to a model that has been developed and operated experimentally.