• Nuclear Medicine and Molecular Imaging
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• v.41 no.4
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• pp.317-325
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• 2007

Purpose: Biological parameters can be quantified using dynamic PET data with compartment modeling and Nonlinear Least Square (NLS) estimation. However, the generation of parametric images using the NLS is not appropriate because of the initial value problem and excessive computation time. In irreversible model, Patlak graphical analysis (PGA) has been commonly used as an alternative to the NLS method. In PGA, however, the start time ($t^*$, time where linear phase starts) has to be determined. In this study, we suggest a new Multiple Linear Analysis for irreversible radiotracer (MLAIR) to estimate fluoride bone influx rate (Ki). Methods: $[^{18}F]Fluoride$ dynamic PET scans was acquired for 60 min in three normal mini-pigs. The plasma input curve was derived using blood sampling from the femoral artery. Tissue time-activity curves were measured by drawing region of interests (ROls) on the femur head, vertebra, and muscle. Parametric images of Ki were generated using MLAIR and PGA methods. Result: In ROI analysis, estimated Ki values using MLAIR and PGA method was slightly higher than those of NLS, but the results of MLAIR and PGA were equivalent. Patlak slopes (Ki) were changed with different $t^*$ in low uptake region. Compared with PGA, the quality of parametric image was considerably improved using new method. Conclusion: The results showed that the MLAIR was efficient and robust method for the generation of Ki parametric image from $[^{18}F]Fluoride$ PET. It will be also a good alternative to PGA for the radiotracers with irreversible three compartment model.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.4 no.1
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• pp.40-49
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• 1999

A laboratory flume experiment, using turbulence-generating acryl tank and natural sediments, was conducted to investigate the effects of salinity, concentration of suspended sediment, turbulence and clay minerals on the flocculation and settling of fine-grained suspended sediments. While experiments were run, a sequence of water samples were taken near the bottom of the tank to analyze the variations of size distribution and relative contents of clay minerals. The results of the salinity experiment indicate that median settling velocity ($W_{50}$) increases linearly with salinity. Different settling processes of suspended sediments under variable concentrations appear to be predictable, depending upon the range of the suspension concentration. At concentrations less than 200 mg/l, $W_{50}$ is rarely varied with concentration probably because of the individual--grain settling mode. In the range of 200 to 13,000 mg/l show $W_{50}$ and concentration a good relationship following an empirical formula: $W_{50}=0.45C^{0.44}$. This relationship, however, no longer holds in concentrations exceeding 13,000 mg/l; instead, a more or less reverse one is shown. This result suggests an effect of hindered settling. The turbulence effect is somewhat different from that of concentration. Turbulence accelerates the flocculation and settling susepended sediments at low concentration (200 mg/l), whereas at high concentration turbulence breaks floes down and impedes the settling. Size distribution of suspended sediments sampled near the bottom of the tank tend to be more negatively skewed and leptokurtic in turbulent conditions compared to those in static conditions. The clay mineral analysis from the sequential water samples shows that over time the content of smectite decreases most rapidly with illite remaining concentrated in suspension. This means that smectite, among other clay minerals, plays the most effective role in the flocculation of fine-grained sediment in saline water.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.38 no.4
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• pp.363-373
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• 2020

During last decades numerous studies generating orthoimage have been carried out. Traditional methods require exterior orientation parameters of aerial images and precise 3D object modeling data and DTM (Digital Terrain Model) to detect and recover occlusion areas. Furthermore, it is challenging task to automate the complicated process. In this paper, we proposed a new concept of true orthoimage generation using DL (Deep Learning). DL is rapidly used in wide range of fields. In particular, GAN (Generative Adversarial Network) is one of the DL models for various tasks in imaging processing and computer vision. The generator tries to produce results similar to the real images, while discriminator judges fake and real images until the results are satisfied. Such mutually adversarial mechanism improves quality of the results. Experiments were performed using GAN-based Pix2Pix model by utilizing IR (Infrared) orthoimages, intensity from LiDAR data provided by the German Society for Photogrammetry, Remote Sensing and Geoinformation (DGPF) through the ISPRS (International Society for Photogrammetry and Remote Sensing). Two approaches were implemented: (1) One-step training with intensity data and high resolution orthoimages, (2) Recursive training with intensity data and color-coded low resolution intensity images for progressive enhancement of the results. Two methods provided similar quality based on FID (Fréchet Inception Distance) measures. However, if quality of the input data is close to the target image, better results could be obtained by increasing epoch. This paper is an early experimental study for feasibility of DL-based true orthoimage generation and further improvement would be necessary.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.56 no.1
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• pp.1-7
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• 2011

In this study, we investigated the antioxidant activities, inhibition activity against ACE (angiotensin converting enzyme) and antitumor activity of extract from Acanthopanax senticosus HARMS fruits for development novel functional resources. In order to understand the factors responsible for the potent antioxidant and antihypertensive ability of fruits in A. senticosus, it has been evaluated for anti-oxidative activity using Fenton's reagent/ethyl linoleate system and for free radical scavenging activity using the l,l-diphenyl-2-picryl hydrazyl free radical generating system. The fruits extract of A. senticosus showed higher antioxidant activities than positive control, ${\alpha}$-tocopherol at all concentrations, while fruits extract of A. senticosus showed same degree of radical scavenging activity with positive control, ${\alpha}$-tocopherol. The ability of fruit extracts from A. senticosus to influence the inhibitory activity of angiotensin converting enzyme (ACE) and xanthine oxidase (XOase) has also been discussed. The activity of growth-inhibitory of fruit extracts of A. senticosus was screened by SRB (sulphorhodamine B) method on diverse cancer cells representing different types of cancers. The fruit extracts of A. senticosus showed moderate inhibition on proliferation of LNCaP and MOLT-4F cells and did not inhibit the proliferation of other cancer cells. The fruit extracts of A. senticosus inhibited the proliferation of cancer cells with $GI_{50}$ values ranging from 5 to $10{\mu}g/mL$. This result revealed that the fruit extracts of A. senticosus was expected to be good candidate for development into source of free radical scavengers, antihypertentive, and anti-tumor agent.

• Korean Journal of Food Science and Technology
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• v.39 no.6
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• pp.669-675
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• 2007

The present study was conducted to explore the anti-inflammatory action of $2-hydroxyethyl-{\beta}-undecenate$ (HPS) purified from Cumin (Cuminum cymium L.) seed against periodontitis. From the study in which human leukocyte was employed to detect the inhibiting effects of 5-lipokygenase and cyclooxygenase, enzymes generating carriers of infection like $LTB_4$ and PGs, as well as of collagenase and elastase, organ-destroying enzymes, following conclusions could be drawn: HPS was found to inhibit leukotrien $B_4$ biosynthesis by stimulating more than 97% of human polymorphonuclear leukocyte (PMNL) with addition of $5\;{\times}\;10^{-2}\;M$ when $IC_{50}$ was set at $2\;{\times}\;10^{-4}\;M$. Ninety-two percent of enzyme activation turned out to be inhibited when $5\;{\times}\;10^{-2}\;M$ was added in a test to prove inhibiting effects of HPS against activation of PMNL 5-lipoxygenase from homogeneous humans and purified 5-lipoxygenase on the market. Besides, $IC_{50}$ for enzyme activation was valued at $2.5\;{\times}\;10^{-4}\;M$, while the value of $IC_{50}$ for purified 5-lipoxygenase was $2.3\;{\times}\;10^{-4}\;M$. The $IC_{50}$ values of COX-activated leukocyte and purified collagenase were $5.1\;{\times}\;10^{-4}\;M$ and $2.3\;{\times}\;10^{-4}\;M$, respectively. Moreover, the value of $IC_{50}$ for activation of leukocyte collagenase was $2\;{\times}\;10^{-3}\;M$, whereas that for purified collagenase was $5\;{\times}\;10^{-2}\;M$. In case of leukocyte elastase, addition of $5\;{\times}\;10^{-2}\;M$ inhibited its activation by 66%. In case of purified one, however, activation of enzyme was inhibited by 25% with addition of $5\;{\times}\;10^{-2}\;M$. Furthermore, the $IC_{50}$ value for activation of leukocyte elastase was revealed to be $7.5\;{\times}\;10^{-3}\;M$. From the virulence test with human gingiva cell, it was shown that, on the second day of cultivation, 47.83% of the cell had been activated when HPS was added by $5\;{\times}\;10^{-2}\;M$. Even the addition of HPS by $1\;{\times}\;10^{-2}\;M$ featured 68.53% of cell activation, suggesting relatively strong toxicity of the substance against gingiva cell.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.52 no.4
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• pp.447-452
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• 2007

This experiment was conducted to enhance the colored potatoes utilization and to determine the biological activity of colored potato extracts. In order to understand the factors responsible for the potent antioxidant and antihypertensive ability of colored potatoes, it has been evaluated for anti-oxidative activity using Fenton's reagent/ethyl linoleate system and for free radical scavenging activity using the 1,1-diphenyl-2-picryl hydrazyl free radical generating system. There were significant differences of antioxidant activities in $50{\mu}g/mL$ extracts treatment among different colored potatoes. About two-fold higher radical scavenging activity was found in 'Daegwan 1-102', 'Daegwan 1-104' and 'Jasim' compared to that in 'Superior'. Based on the flesh color tested, potatoes with purple tuber showed higher radical scavenging activity than red potatoes, while white potato showed the lowest radical scavenging activity. The ability of 80% ethanol extracts from colored potatoes to influence the inhibitory activity of angiotensin converting enzyme(ACE) and xanthine oxidase(XOase) has also been investigated. Expect 'Jasim', the high levels of inhibition activity of xanthine oxidase in two colored potatoes such as 'Daegwan 1-102' and 'Daegwan 1-104' were highly correlated to $IC_{50}$ values of ACE inhibition activity. The various therapeutic benefit claims in the new functional medicinal usage of colored potatoes ascribed to the phenolic compounds and anthocyanin. This result revealed that the extracts of colored potatoes are expected to be good candidate for development into source of free radical scavengers and anti-hypertentive agent.

• Economic and Environmental Geology
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• v.50 no.5
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• pp.341-352
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• 2017

Along with Cs-137 (half-life: 30.17 years), Sr-90 (half-life: 28.8 years) is one of the most important environmental monitoring radioactive elements. Rapid and easy monitoring method for Sr-90 using Laser-Induced Breakdown Spectroscopy (LIBS) has been studied. Strontium belongs to a bivalent alkaline earth metal such as calcium and has similar electron arrangement and size. Due to these similar chemical properties, it can easily enter into the human body through the food chain via water, soil, and crops when leaked into the environment. In addition, it is immersed into the bone at the case of human influx and causes the toxicity for a long time (biological half-life: about 50 years). It is a very reductive and related with the specific reaction that makes wet analysis difficult. In particular, radioactive strontium should be monitored by nuclear power plants but it is very difficult to be analysed from high-cost problems as well as low accuracy of analysis due to complicated analysis procedures, expensive analysis equipment, and a pretreatment process of using massive chemicals. Therefore, we introduce the Laser-Induced Breakdown Spectroscopy (LIBS) analysis method that analyzes the elements in the sample using the inherent spectrum by generating plasma on the sample using pulse energy, and it can be analyzed in a few seconds without preprocessing. A variety of analytical plates for samples were developed to improve the analytical sensitivity by optimizing the laser, wavelength, and time resolution. This can be effectively applied to real-time monitoring of radioactive wastewater discharged from a nuclear power plant, and furthermore, it can be applied as an emergency monitoring means such as possible future accidents at a nuclear power plants.

• Journal of the Korean Society of Marine Environment & Safety
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• v.16 no.2
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• pp.141-151
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• 2010

Harmful algal blooms (HABs), commonly known as red tides, are aquatic phenomena caused by the rapid growth and accumulation of certain microalgae, which can lead to marked discoloration of surface waters, and severe impacts on public health, commerce, and the environment. In South Korea, the red tides have been a serious and recurrent problem, especially along the south coast. Plenty of yellow loess was used to control an outbreak of the red tides for 15 years from 1996 until now. Yellow loess was almost sprayed in the vicinity of a large fish farming industry. In this research, the distribution characteristics and density distribution of zooplankton were investigated in autumn (Oct. 2008) and spring (Apr. 2009) using volume backscattering strength (SV) calculated by the zooplankton collected with north pacific standard (NORPAC) net and the echo intensity measured with ADCP at stations on the study area in the spraying ocean of yellow loess (SOYL), and the non-spraying ocean of yellow ocean (NOYL) by the red tide generating every year. The species number and the individuals per unit volume of the zooplankton collected in NOYL was high and it which was collected in SOYL was low. As a result of comparing the volume backscattering strength ($SV_c$) calculated by species and length of the zooplankton collected with NORPAC net with the volume backscattering strength ($SV_m$) calculated by the echo intensity measured with ADCP at stations on the study area, although $SV_c$ and $SV_m$ of NOYL were generally in agreement, $SV_m$ of SOYL was higher than $SV_c$ 4.3dB, i.e. ADCP is greatly influenced by suspended solid in SOYL. The horizontal distribution map of $SV_m$ at the study area in autumn (Oct. 2008) and spring (Apr. 2009) was drawn. $SV_m$ of SOYL is higher than NOYL and autumn is higher than spring. $SV_m$ can suppress the overestimate or underestimate of $SV_c$.

• Journal of the East Asian Society of Dietary Life
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• v.18 no.6
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• pp.939-948
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• 2008

The effects of goat's beard (Aruncus dioicus var ramtschaticus Hara) ethanol extracts (AD) on the streptozotocin-induced diabetic symptoms and oxidative stress in rats were assessed. Experimental plots were divided into normal controls (NC), diabetes controls (DM), diet with 0.3% AD after diabetes induction (SA), and diet with 0.6% AD after diabetes induction (SB), then fed for 5 weeks. In the SA and SB groups as compared with the DM group, diabetic symptoms including weight loss, increase in feed and water intake, and enlargement of the liver and kidney were improved. The levels of blood glucose and serum fructosamine were reduced by $17.9{\sim}27.2%$ and $25.6{\sim}32.6%$, respectively. The activities of alanine aminotransferase, aspartate aminotransferase and the levels of triglycerides, total cholesterol, and LDL-cholesterol in the serum were reduced by $25.6{\sim}30.3$, $42.37{\sim}55.51$, $26.85{\sim}30.44$ and $37.29{\sim}39.11%$, respectively, whereas the level of HDL-cholesterol was increased by $37.29{\sim}39.11%$. Hepatic total (T) and O type (O) activities of xanthine oxidoreductase, O/T ratio(%) and level of lipid peroxide were significantly decreased, while the level of glutathione was increased, and also the activities of superoxide dismutase and glutathione S-transferase were increased by $56.84{\sim}94.90%$ and $57.14{\sim}68.92%$, respectively. In the above results, it was noted that AD has an antidiabetic effect which alleviated hyperglycemia and the AD reduced and/or prevented the tissue damage caused by diabetes yia the inhibition of reactive oxygen species (ROS) generating systems concurrent with an increase in ROS scavenging.

• Journal of the Korean Institute of Landscape Architecture
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• v.44 no.6
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• pp.60-72
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• 2016

This study aims to suggest strategies of development and management for large parks by examining experimental cases of park governance models related to a shift away from public administration. The shifts towards governance as well as public-private partnership in city parks have involved the need for new public management. This study has analyzed two exemplary cases of Presidio Park and Sydney Harbour National Park in the aspects of planning process and management strategies, as the results derived the meaning and effect of park governance management and is also an essential prerequisite for the achievement of the model. There are six dimensions of research frames--namely policy, governance, partnership, finances and funds, design and maintenance-management, and evaluation-monitoring-taken as the basis for this study. Through the analysis, several key characteristics of these cases were elicited. First, the park planning process must be consistent in carrying a policy from planning to implementation, and furthermore, an independent operation body which can properly authorize an execution and uphold its responsibility from the public could serve in adaptable park services. Second, it has been suggested to build various partnerships with PAs and NGOs, private corporations, community groups, and academic institutes that allow it to expand the diversity of the park activities. Third, there has been experimental exploration to achieve a financially self-sufficient model by establishing internal revenue models and hence allow the reduction of reliance on public finances. The result of this type of park management would allow for improving park quality and make the park space a vital part of the local economy. Fourth, the strategies for a local community's participation are needed to allow the community to become a producer as well as a consumer. This study shows that the direction and significance of the park governance model regarding the fact that the plans sought by the two parks are extending the layout of public-centered discussion to the private sector and the third non-governmental sector including to the local community group. This shows both implications and limitations, such as the risk of privatization through non-governmental activities at the park or the violation of essential functions as a public good due to a profit-generating management policy for securing financial self-sufficiency. At the current point in which plans are under way for the development and management of large parks, a park governance model requires continuous study and expansion of discussion in the future.