• Journal of Food Hygiene and Safety
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• v.32 no.4
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• pp.290-297
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• 2017

The purpose of this study was developed for the determination of tridemorph in agricultural commodities samples. Tridemorph residues in samples were extracted with acetonitrile, partitioned with saline water, and then purified using and aminopropyl ($NH_2$) SPE catridge. The purified samples were quantified and confirmed via liquid chromatograph-tandem mass spectrometer (LC-MS/MS) in positive ion mode using multiple reaction monitoring (MRM). Matrix-matched calibration curves were linear over the calibration ranges (0.005~2.5 ng) into a blank extract with $r^2$ > 0.999. The limits of detection and quantification were 0.001 and 0.005 mg/kg, respectively. The average recovery ranged between 75.9% and 103.7% at different concentration levels (LOQ, 10 LOQ, 50 LOQ, n = 5) with relative standard deviations (RSDs) less than 9.0%. An interlaboratory study was conducted to validate the method by Korea Advanced Food Research Institute. The average recovery ranged between 87.0% and 109.2% at different concentration levels (LOQ, $10{\times}LOQ$, $50{\times}LOQ$, n = 5) with relative standard deviations (RSDs) less than 8.0%. All values were consistent with the criteria ranges requested in the Codex guidelines (CAC/GL40, 2003) and Food Safety Evaluation Department guidelines (2016). The results prove that the developed analytical methods is accurate, effective and sensitive for tridemorph determination.

• Journal of Food Hygiene and Safety
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• v.35 no.5
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• pp.503-512
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• 2020

To enhance the usability of puffed rice, we evaluated the quality characteristics and antioxidant activity of vinegar made with puffed rice and lemon balm. First, puffed rice containing lemon balm extracts was fermented for alcohol production. The alcoholic fermented liquid was adjusted to an alcohol content of 6% and an initial acidity of 2% for vinegar fermentation. The pH and alcohol content of the lemon balm vinegar decreased overall as fermentation progressed. The total acidity was 5.20±0.01% (2.0% lemon balm) to 5.80±0.01% (0.0% lemon balm) on the 15th day of fermentation, and the total acidity was slightly lower as the amount of added lemon balm was increased. Citric, succinic, and acetic organic acids were detected in the vinegar and the acetic acid content was highest at 4.81% to 5.37% on the 15th day of fermentation. We found that the total polyphenol and total flavonoid content of the lemon balm vinegar increased as we added lemon balm, and the content on the 15th day of fermentation was 179.4±4.5 (0.0% lemon balm) - 340.8±2.6 mg/kg (2.0% lemon balm) and 1.5±0.3 (0.0% lemon balm) - 31.7±0.3 mg/kg (2.0% lemon balm), respectively. The higher the amount of lemon balm added, the higher the DPPH radical scavenging activity, the FRAP (reducing power), and the ABTS radical scavenging activity. Moreover, those activities after 2.0% lemon balm treatment were 82.99±0.61%, 1.08±0.01 abs., and 87.67±0.68%, respectively, on the 15th day of fermentation. These results suggest that vinegar with added lemon balm may be used as an antioxidant agent.

• Journal of Food Hygiene and Safety
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• v.35 no.5
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• pp.430-437
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• 2020

This is an approach study on the sensory properties (taste and odor) of 15 types of Korean conventional soups and stews using electronic nose and tongue. The relative sensor intensity for the taste components of the samples using electronic tongue was demonstrated. By SRS (sourness) sensor, sogogi-baechuguk (beef and cabbage soup) had the highest rate of 9.0. The STS (saltiness) sensor showed the highest score of 8.2 for ojingeoguk (squid soup). For the UMS (umami) sensor, which identifies savoriness, the sogogi-baechuguk was the highest at 10.1. The SWS (sweetness) sensors showed relatively little difference, with sigeumchi-doenjangguk (spinach and bean paste soup) at the highest of 7.3. According to the BRS sensor, which tests for bitterness, the siraegi-doenjangguk (dried radish green and bean paste soup) was the highest at 7.8. By principal component analysis (PCA), we observed variances of 56.21% in principal component 1 (PC1) and 25.23% in PC2. For each flavor component, we observed -0.95 and -0.20 for factor loading of PC1 and PC2 for SRS sensors, 0.96 and 0.14 for STS sensors, and -0.94 and 0.22 for PC1 and PC2 for UMS sensors, and PC1 and 0.22 for PC1 and PC2 loading for SWS sensors. The similarity between the samples identified by clustering analysis was largely identified by 4 clusters. A total of 25 kinds of volatile compounds in 15 samples were identified, and the ones showing the highest relative content in all samples were identified as ethanol and 2-methylthiophhene. The main ingredient analysis confirmed variances of 28.54% in PC1 and 20.80% in PC2 as a result of the pattern for volatile compounds in 15 samples. In the cluster analysis, it was found to be largely classified into 3 clusters. The data in this study can be used for a sensory property database of conventional Korean soups and stews using electronic sensors.

• Horticultural Science & Technology
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• v.32 no.3
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• pp.346-352
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• 2014

This research was carried out to investigate the effect of supplemental lighting on stable productivity of paprika (Capsicum annuum L.) during low radiation period of winter season. The supplemental lighting sources used in this research were high pressure sodium (HPS) and lighting emitting plasma (LEP). Photosynthetic photon flux density (PPFD) emitted from both lamps decreased as vertical distance from lamp increased. The PPFD of LEP lamps were twice more than that of the HPS lamp per unit distance, but the rate of decreased PPFD of t he LEP per unit distance was higher than that of HPS lamp. And different degrees of PPFD between HPS and LEP lamps by horizontal distance had a smaller degree of difference than by vertical distance at the 100 cm away point. As daily average PPFD measured at the top of the plant under the supplemental lighting during January, the supplemental lighting significantly increased radiation. Radiation of HPS and LEP lighting was 137% and 315% higher than control (without supplemental lighting = sunlight). Air temperature in the top of the plant was not significant different among treatments. HPS and LEP lighting had no effect on increase of flower settings. Leaf length and width with LEP lighting was the longest, photosynthetic was higher than those of other treatments. Supplemental lighting treatments significant increased fruit length and diameter. Especially LEP lighting treatment had a greater effect on fruit length and diameter. In conclusion, LEP lighting treatment during low radiation period greatly affected growth and production of paprika. Further research will be required for the suitable application of LEP lighting in paprika production.

• Horticultural Science & Technology
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• v.32 no.3
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• pp.318-329
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• 2014

In order to gain insight into the physiological responses of plants to high temperature stress, the effects of temperature on Chinese cabbage (Brassica campestris subsp. napus var. pekinensis cv. Detong) were investigated through analyses of photosynthesis and chlorophyll fluorescence under 3 different temperatures in the temperature gradient tunnel. Growth (leaf length and number of leaves) during the rosette stage was greater at ambient $+4^{\circ}C$ and ambient $+7^{\circ}C$ temperatures than at ambient temperature. Photosynthetic $CO_2$ fixation rates of Chinese cabbage grown under the different temperatures did not differ significantly. However, dark respiration rate was significantly higher in the cabbage that developed under ambient temperature relative to elevated temperature. Furthermore, elevated growth temperature increased transpiration rate and stomatal conductance resulting in an overall decrease of water use efficiency. The chlorophyll a fluorescence transient was also considerably affected by high temperature stress; the fluorescence yield $F_J$, $F_I$, and $F_P$ decreased considerably at ambient $+4^{\circ}C$ and ambient $+7^{\circ}C$ temperatures, with induction of $F_K$ and decrease of $F_V/F_O$. The values of RC/CS, ABS/CS, TRo/CS, and ETo/CS decreased considerably, while DIo/CS increased with increased growth temperature. The symptoms of soft-rot disease were observed in the inner part of the cabbage heads after 7, 9, and/or 10 weeks of cultivation at ambient $+4^{\circ}C$ and ambient $+7^{\circ}C$ temperatures, but not in the cabbage heads growing at ambient temperature. These results show that Chinese cabbage could be negatively affected by high temperature under a future climate change scenario. Therefore, to maintain the high productivity and quality of Chinese cabbage, it may be necessary to develop new high temperature tolerant cultivars or to markedly improve cropping systems. In addition, it would be possible to use the non-invasive fluorescence parameters $F_O$, $F_V/F_M$, and $F_V/F_O$, as well as $F_K$, $M_O$, $S_M$, RC/CS, ETo/CS, $PI_{abs}$, and $SFI_{abs}$ (which were selected in this study), to quantitatively determine the physiological status of plants in response to high temperature stresses.

• 한국공간정보시스템학회:학술대회논문집
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• 2004.12a
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• pp.169-181
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• 2004

SK Telecom has already constructed GIMS system as the base common framework of LBS/GIS service system based on OGC(OpenGIS Consortium)'s international standard for the first mobile vector map service in 2002, But as service content appears more complex, renovation has been needed to satisfy multi-purpose, multi-function and maximum efficiency as requirements have been increased. This research is for preparation ion of GML3-based platform to upgrade service from GML2 based GIMS system. And with this, it will be possible for variety of application services to provide location and geographic data easily and freely. In GML 3.0, it has been selected animation, event handling, resource for style mapping, topology specification for 3D and telematics services for mobile LBS multimedia service. And the schema and transfer protocol has been developed and organized to optimize data transfer to MS(Mobile Stat ion) Upgrade to GML 3.0-based GIMS system has provided innovative framework in the view of not only construction but also service which has been implemented and applied to previous research and system. Also GIMS channel interface has been implemented to simplify access to GIMS system, and service component of GIMS internals, WFS and WMS, has gotten enhanded and expanded function.

• Korean Journal of Ecology and Environment
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• v.49 no.1
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• pp.42-50
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• 2016

The purpose of this study is to set the direction to manage national parks to cope with climate change, and offer basic data to establish the relevant policies. Towards this end, this study analyzed the current and future climate change vulnerability of national parks using the 24 proxy variables of vulnerability in the LCCGIS program, a tool to evaluate climate change vulnerability developed by the National Institute of Environmental Research. To analyze and evaluate the current status of and future prospect on climate change vulnerability of national parks, the proxy variable value of climate exposure was calculated by making a GIS spatial thematic map with $1km{\times}1km$ grid unit through the application of climate change scenario (RCP8.5). The values of proxy variables of sensitivity and adaptation capability were calculated using the basic statistics of national parks. The values of three vulnerability evaluation items were calculated regarding the present (2010s) and future (2050s). The current values were applied to the future equally under the assumption that the current state of the proxy variables related to sensitivity and adaptation capability without a future prediction scenario continues. Seoraksan, Odaesan, Jirisan and Chiaksan National Parks are relatively bigger in terms of the current (2010s) climate exposure. The national park, where the variation of heat wave is the biggest is Wolchulsan National Park. The biggest variation of drought occurs to Gyeryongsan National Park, and Woraksan National Park has the biggest variation of heavy rain. Concerning the climate change sensitivity of national parks, Jirisan National Park is the most sensitive, and adaptation capability is evaluated to be the highest. Gayasan National Park's sensitivity is the lowest, and Chiaksan National Park is the lowest in adaptation capability. As for climate change vulnerability, Seoraksan, Odaesan, Chiaksan and Deogyusan National Parks and Hallyeohaesang National Park are evaluated as high at the current period. The national parks, where future vulnerability change is projected to be the biggest, are Jirisan, Woraksan, Chiaksan and Sobaeksan National Parks in the order. Because such items evaluating the climate change vulnerability of national parks as climate exposure, sensitivity and adaptation capability show relative differences according to national parks' local climate environment, it will be necessary to devise the adaptation measures reflecting the local climate environmental characteristics of national parks, rather than establishing uniform adaptation measures targeting all national parks. The results of this study that evaluated climate change vulnerability using climate exposure, sensitivity and adaptation capability targeting Korea's national parks are expected to be used as basic data for the establishment of measures to adapt to climate change in consideration of national parks' local climate environmental characteristics. However, this study analyzed using only the proxy variables presented by LCCGIS program under the situation that few studies on the evaluation of climate change vulnerability of national parks are found, and therefore this study may not reflect overall national parks' environment properly. A further study on setting weights together with an objective review on more proper proxy variables needs to be carried out in order to evaluate the climate change vulnerability of national parks.

• Korean Journal of Ecology and Environment
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• v.46 no.1
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• pp.33-40
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• 2013

From March 2012 to January 2013, this study was conducted as a part of the project for making a precise electronic ecological zoning map of vegetation on a highly reduced scale of 1 to 5,000 with a view to improving management efficiency of national parks and enlarging the availability of the data produced from the basic research monitoring the resources of national parks. For the research accuracy and rapidity, a vegetation map was specially created for the on-the-site-vegetation research. To make the map more meticulous, we categorized the vegetation database into five groups: broadleaved forest, coniferous forest, mixed forest, rock vegetation and miscellaneous one. After comparing the results of the data built for the vegetation research and the actual research findings, it was made clear that vegetation of both categories was almost the same in case of broad-leaved forest with 72.20% and 78.45% respectively, and also equivalent in other groups like, for example, coniferous forest (16.70%, 13.41%), mixed forest (9.50%, 7.49%) and rock vegetation (0.60%, 0.15%). According to the precise vegetation map produced from the research, the deciduous broad-leaved forest was the most widely prevalent type in the correlated hierarchical classification of vegetation, occupying 65.78% of the overall vegetation. It was followed by mountain valley forest (15.17%), coniferous forest (10.90%), and plantation forest (7.00%) in order. It is particularly noteworthy that Mt. Deogyusan national park has retained a very stable and versatile forest vegetation in the outstanding state since approximately 20% of the mountain turns out to belong to the I grade vegetation conservation classification which contains climax forests, unique vegetation, subalpine vegetation, matured stands which are older than 50 years and etc.

• Korean Journal of Ecology and Environment
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• v.41 no.2
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• pp.206-215
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• 2008

Temporal and spatial distributions of salinity, temperature, dissolved oxygen (DO), and turbidity were investigated at seven sites in the upper regions of brackish Lake Sihwa with a limited water exchange, from March to October 2005. During the study period, salinity and temperature varied $0.1{\sim}29.9\;psu$ and $4.7{\sim}28.1^{\circ}C$, respectively, depending on seasons and sites sampled. A distinct halocline profile showing the maximum density gradient (difference over $20\;psu\;m^{-1}$ between surface and bottom layers) was observed during the rainy season, due to the decrease of salinity in surface layers by freshwater inflow. This result implies that rainfall event is the important factor forming the halocline. On the other hand, the depth and location of haloeline varied with the amount of seawater through the sluice gates and the operation systems (inflow or outflow). High DO (over 300% saturation) was observed at surface layer above the halocline in April when red tide occurred, whereas low DO (below 20% saturation) was at the bottom layer below the halocline in the rainy season. Turbidity ranged $1.5{\sim}80.3\;NTU$ showing the maximum turbidity at the layers above or upper the halocline. As a result, the distributions of DO and turbidity in the upper regions of brackish Lake Sihwa were largely affected by the variation of salinity. Also, when the halocline was formed, the water quality between upper and lower water layers may be expected completely different. This study suggests that the physicochemical characteristics of water in the brackish regions are closely associated with the causes of eutrophication such as red tide and DO deficit.

• Korean Journal of Ecology and Environment
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• v.50 no.1
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• pp.57-69
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• 2017

Overwintering and succession of phytoplankton community with physicochemical and biological characteristics were investigated in pilot culture system. Water and phytoplankton samples were collected twice a week from February 23 to June 28, 2016. A total of 17 overwintering taxa including cyanophyceae, chlorophyceae, bacillariophyceae were identified in the experimental group in winter (February), and these overwintering species showed a marked succession pattern along with environment changes. In the process of phytoplankton succession, a total of 56 species in 28 genera were identified in two (experimental, control) pilot culture system. In the experimental group, 52 phytoplankton species in 24 genera were identified, and the number of taxa was highest in chlorophyceae (35 species), followed by Bacillariophyceae (9 species), Cyanophyceae (5 species) and others (3 species). In the control group, 25 phytoplankton species in 14 genera were classified and these taxa consisted of 17 chlorophyceae, 3 cyanophyceae, 2 Bacillariophyceae and 3 others. The standing crops ranged from 40 to $325,450cells\;mL^{-1}$ in the experimental group, and from 900 to $37,100cells\;mL^{-1}$ in the control group, respectively. The dominant species were represented by Monoraphidium minutum, Microcystis aeruginosa, Rhodomonas lacustris, Ankyra judai and Chlorella vulgaris in the experimental group; and M. minutum and Coenochloris cf. pyrenoidosa in the control group. In conclusion, overwintering and succession of predominant phytoplankton species developed due to interactions of internal environmental factors(physicochemical and biological factors) in the pilot culture system.