• Korean Journal of Ecology and Environment
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• v.41 no.2
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• pp.188-197
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• 2008

This research was a preliminary case study to determine the levels of total mercury in the tissues of sentinel species (Zacco platypus) and ecological health in relation to habitat characteristics and chemical conditions. We collected fishes in Gap Stream during June$\sim$October 2007 and analyzed the total mercury from five types of tissues such as liver, kidney, gill, vertebrae and muscle of Zaceo platypus using Direct Mercury Analyzer (DMA-80, US EPA Method 7473). Mean concentrations of total [Hg], based on all tissues, was 67.2 and $20.7\;{\mu}g\;kg^{-1}$, in the upstream and downstream site, respectively, indicating 3 times greater level in the upstream. In other words, the levels were higher in the pristine upstream than the downstream influenced by the wastewater disposal plant. Chemical water quality, based on BOD, COD and nutrients (TN, TP) showed that severe degradation occurred in the downstreams than the upstreams. Index of Biological Integrity (IBI) using fish multi-metric model averaged 32, indicating a "good$\sim$fair" condition and varied from 42 (excellent$\sim$good) at S2 to 22 (fair$\sim$poor) at S5 depending on the sites sampled. Qualitative Habitat Evaluation Index (QHEI) in the all sites averaged 142, which was judged as "good" habitat health, but showed a high variation (181 in Site 2 vs. 67 in Site 5). Overall data suggest that health conditions, based on IBI and QHEI, was better in the upstream sites but the mercury bioaccumulation levels in the fish tissues were opposite. We believe that measurements of various parameters are required for a diagnosis of integrative ecosystem health.

• Korean Journal of Food Science and Technology
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• v.42 no.5
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• pp.613-619
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• 2010

Three varieties of taro flours (Altoran, Josaengjong, and Jaeraejong) were analyzed to evaluate their nutrient composition and physicochemical properties. Moisture contents of the three taro cultivars varied from 5.74-10.30%. Among the three cultivars, Altoran flour had higher protein and fat contents than other cultivars. There were 17 kinds of amino acids in the three taro flours. The major fatty acids in the three taro flours were linoleic acid (46.5-51.4%), palmitic acid (21.7-25.8%), and oleic acid (12.3-18.7%), and two thirds of the total fatty acids were unsaturated fatty acids. Potassium, phosphorus, magnesium, and calcium were the most plentiful minerals in the three taro flours, and the free sugars were glucose, fructose, and sucrose. The total dietary fiber contents of the three taro flours ranged from 12.97 to 17.60%. From these results, Altoran contained a high level of dietary fiber, minerals, essential amino acids, and free sugars. Jaeraejong showed the highest water absorption index. The water soluble index of Altoran was higher than that of the other cultivars. From the differential scanning calorimeter results, the gelatinization temperatures of the three taro flours were $84.98-89.91^{\circ}C$. The pasting temperature of the three taro flours was from 46.77 to $49.30^{\circ}C$ by rapid visco-analyzer. Among these varieties, Josaengjong had the highest peak viscosity and final viscosity, whereas Altoran had the lowest. These taro cultivars are expected to be potential material for application in taro processed foods, due to their gelatination and pasting properties.

• Economic and Environmental Geology
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• v.40 no.5
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• pp.517-535
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• 2007

Two distinctive Mesozoic hydrothermal systems occurred in South Korea: the Jurassic/Early Cretaceous(ca. $200{\sim}130$ Ma) deep-level ones during the Daebo orogeny and the Late Cretaceous/Tertiary(ca. $110{\sim}45$ Ma) shallow hydrothermal ones during the Bulgugsa event. The Mesozoic hydrothermal system and the metallic mineralization in the Korean Peninsula document a close spatial and temporal relationship with syn- to post-tectonic magmatism. The calculated ${\delta}^{18}O_{H2O}$ values of the ore-forming fluids from the Mesozoic metallic mineral deposits show limited range for the Jurassic ones but variable range for the Late Cretaceous ones. The orogenic mineral deposits were formed at relatively high temperatures and deep-crustal levels. The mineralizing fluids that were responsible for the formation of theses deposits are characterized by the reasonably homogeneous and similar ranges of ${\delta}^{18}O_{H2O}$ values. This implies that the ore-forming fluids were principally derived from spatially associated Jurassic granitoids and related pegmatite. On the contrary, the Late Cretaceous ferroalloy, base-metal and precious-metal deposits in the Taebaeksan, Okcheon and Gyeongsang basins occurred as vein, replacement, breccia-pipe, porphyry-style and skarn deposits. Diverse mineralization styles represent a spatial and temporal distinction between the proximal environment of subvolcanic activity and the distal to transitional condition derived from volcanic environments. The Cu(-Au) or Fe-Mo-W deposits are proximal to a magmatic source, whereas the polymetallic or the precious-metal deposits are more distal to transitional. On the basis of the overall ${\delta}^{18}O_{H2O}$ values of various ore deposits in these areas, it can be briefed that the ore fluids show very extensive oxygen isotope exchange with country rocks, though the ${\delta}D_{H2O}$ values are relatively homogeneous and similarly restricted.

• Journal of Life Science
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• v.23 no.7
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• pp.893-903
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• 2013

The purpose of this study was to evaluate the effects of dietary Flammulina velutipes mycelium (FVM) on physico-chemical properties and nutritional components of chicken meat. Ninety-six broiler chicks (HanHyup No. 3, Korea) were divided into four groups: control (basal diet), T1 (supplemented with 1% FVM), T2 (3%), and T3 (5%). Broiler chicks in each group were slaughtered at 7 weeks of age, and their breast and thigh meat were collected. Lightness ($L^*$) and yellowness ($b^*$) in the T2 and T3 groups were higher than in the control group (p<0.05). The loss of breast meat during cooking was increased in the T1, T2, and T3 groups, and the water-holding capacity of the breast meat was also decreased in these three groups (p<0.05). The water-soluble protein solubility was lower in the T1, T2, and T3 groups than in the control group (p<0.05), but the salt-soluble protein solubility in these three groups was higher than that in the control group (p<0.05). The crude fat content of the breast meat was decreased and that of the thigh meat was increased as the level of FVM was increased (p<0.05). The unsaturated fatty acid content of the breast meat was higher in the T2 and T3 groups than in the control group (p<0.05). The free amino acid content was high in the T1, T2, and T3 groups compared to the control. In conclusion, these results showed that feeding with 3% and 5% FVM increased the L and b values in thigh meat, improved the salt-soluble protein solubility, and increased the content of unsaturated fatty acids and free amino acids.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.37 no.1
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• pp.239-246
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• 2017

There are various transversal structures (small dams or drop structures) in median and small streams in Korea. Most of them are concrete structures and it is so hard to exclude low-level water. Unless drainage valves and/or gates would not be installed near bottom of bed, sediment from upstream should be deposited and also contaminants attached to the sediments would devastatingly threaten the water quality and ecosystem. One of countermeasures for such problem is the bypass pipe installed underneath the transversal structure. However, there is still issued whether it would be workable if the gravels and/or stones would roll into and be not excluded. Therefore, in this study, the conditions to exclude the rip stone which enter into the bypass pipe was reviewed. Based on sediment transport phenomenon, the behavior of stones was investigated with the concepts from the critical shear stress of sediment and d'Alembert principle. As final results, the basis condition (${\tau}_c{^*}$) was derived using the Lagrangian description since the stones are in the moving state, not in the stationary state. From hydraulic experiments the relative velocity could be obtained. In order to minimize the scale effect, the extra wide channel of 5.0 m wide and 1.0 m high was constructed and the experimental stones were fully spherical ones. Experimental results showed that the ratio of flow velocity to spherical particle velocity was measured between 0.5 and 0.7, and this result was substituted into the suggested equation to identify the critical condition wether the stones were excluded. Regimes about the exclusion of stone in bypass pipe were divided into three types according to particle Reynolds number ($Re_p$) and dimensionless critical shear force (${\tau}_c{^*}$) - exclusion section, probabilistic exclusion section, no exclusion section. Results from this study would be useful and essential information for bypass pipe design in transveral structures.

• Journal of the Korean Institute of Landscape Architecture
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• v.38 no.5
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• pp.113-121
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• 2010

Shumi-sen(須彌山), built by Nohjagong(路子工) in the southern garden of the Palace Garden during the Asuka Period, is understood as being Sumeru based on an Indian perspective of the theory of the origin of universe. It is also viewed as Mt. Myogoh from a Chinese Buddhist worldview. It is thought to be a type of assembled stone structure with Poong-ryoon (風輪)-Su-ryoon(水輪)-Geum-ryoon(金輪)-Ji-ryoon(地輪) carved into each of the 4 stone pieces. These building shapes are thought to have been utilized as stone for exterior construction as opposed to those structures built during the Shilla Period of China and Korea. Aside from Nohjagong's record of Shumi-sen, most of the records from Japan's period of the time suggest that Shumi-sen was an important element that played a role in the scenery of the seasonal outdoor gardens. It is also thought, from the sentences and expressions surrounding the records, that a combination of the seasonal sceneries was utilized centered on Shumi-sen, and that they were all used during festival events. From a perspective of analysis and interpretation dependent on the limited literature and on observation, it cannot be verified whether the Mt. Sumeru Stone(須彌山石) excavated from the Stone God Ruins is the same Shumi-sen that Nohjagong built along with Okyo(吳橋), but it is thought that the 'Shumi-sen type stone structure' that was later built repeatedly as part of the palace garden facilities is identical to the Shumi-sen built at the Imperial Palace's southern garden, or at least a re-built structure based on the Shumi-sen that Nohjagong built with stones and ponds used to create the foundation. Thus, Shumi-sen that Nohjagong supposedly built along with Okyo is suspected to be a figurative rock arrangement and, at the same time, a miniaturized scenic rock arrangement(縮景樹石) that maximized the shape of Buddhism's Shumi-sen. On the other hand, the surface pattern on Mt. Sumeru Stone is very similar to the multi -layers of mountainous pattern icons expressed in the patterns of the Great Golden Incense Burner(百濟金銅大香爐) or Mountain-Water Scenery Sculptural Brick(山水山景紋?) that were built during the Baekjae pcriod aod the rear side of Hwalsuk-jebul Basal Byungipsang(滑石諸佛菩薩竝立像); it is suspected that similar patterns would have been used if patterns were made on Shumi-sen that Nohjagong built. Also in consideration of the physical theory of MI. Sumeru Stone, the Siphon theory of using a pressure difference in water level was applied to the fountain facilities of Mt. Sumeru Stone that seemed to have been built from the practical rock arrangement perspective for the purpose of feasts, etc.

• Korean Journal of Food Science and Technology
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• v.42 no.2
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• pp.204-209
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• 2010

This study was conducted to investigate the anti-diabetic activity of Kocat-D1, which is widely used in traditional medicine to treat diabetes in Shandong, China. Sprague Dawley rats (8 weeks of age) were separated into 4 groups: a normal control, streptozotocin (STZ)-induced diabetic rat group (DM control), Kocat-D1-1 (diabetic rat treated with 0.25 g/kg/day hot water extract), and Kocat-D1-2 (diabetic rat treated with 1 g/kg/day hot water extract). After eight weeks of treatment, the fasting blood glucose levels of the Kocat-D1-1 ($334.3{\pm}32.9\;mg/dL$) and Kocat-D1-2 group ($259.5{\pm}35.0\;mg/dL$) were significantly lower when compared to the DM control group ($451{\pm}42.6\;mg/dL$). Furthermore, the levels of glutamate oxaloacetate transaminase (GOT), glutamate pyruvate transaminase (GPT), albumin and high-density lipoprotein (HDL) cholesterol in the serum of the Kocat-D1-2 group were significantly normalized when compared to the DM control group. However, significant differences were not observed between the Kocat-D1-1 group and the DM control group. Histochemical staining of the liver of the Kocat-D1-2 group revealed no fat accumulation. The insulin level was significantly upregulated in the Kocat-D1-2 group ($0.13{\pm}0.02\;ng/mL$) when compared to the DM control group ($0.05{\pm}0.04\;ng/mL$). The relative volume of $\beta$-cells in the pancreas of the Kocat-D1-2 group ($49.4{\pm}4.2%$) also increased significantly when compared to the DM control group ($12.9{\pm}7.9%$). These results suggest that Kocat-D1 exerts an anti-hyperglycemic effect through the enhancement of insulin secretion.

• The Journal of Korean Philosophical History
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• no.52
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• pp.9-35
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• 2017

This article is to study the life and philosophy of Jonjae Gidaeseung, who was at strife with his days and did not negotiate with himself, with focus on two concepts of buron(不穩, unrest) and 'sympathy'. It is the fact that to study the traditional philosopher is likely to be enlightening. In order to prevent the risk, we need to define first the concept of unrest as including anxiety to critical resistance. Also, I would like to propose the concept of sympathy in order to grasp the function of his mind which judges whether his feelings and actions are valid from an emotional horizon of unrest. Methodologically this article is to adopt a transversal and correlative thinking by combining an east Asian Confucian traditional concept unrest with a modern one space. It is because this research is to show a significant meaning when we study highlighted and hidden layers of our life and politics in 'now-here' and the 'between space' even though this transversal and correlative study shows the horizon of his life. This article is to investigate how a case is structured by occurrences and divergences and reinterpret a meaning from an emotional horizon. This process is done centering on two terms Guchatuan(pursuing ease ignobly), and Suwolbingho(moon reflected in the water and ice in a bottle), which is the source of Bingwoldang. The two terms were used by Jonjae himself. The latter shows an opposite meaning from the first and is accordingly a way by which we can look into his life and days. My research of Jonjae's life and politics from the emotional-philosophical level is original in that it reveals emotional traces beyond his philosophical ideas which previous studies did not show. In this article, I showed that Gobong was ambitious and resolute, and definite in his judgment and therefore was not good at controlling his uprightness. Also he was too straightforward to purify a language. His unrest characters made him conflict with old ministers and high ranking officials and therefore they avoided him even thought he was excellent in writing and learning and talented. He was oriented toward living by goodness and right Ways, which is summed up as Gisesa(vague movement, situational advantage, and death).

• Journal of The Korean Society of Agricultural Engineers
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• v.61 no.6
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• pp.111-121
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• 2019

Evapotranspiration (ET) of vegetation is one of the major components of the hydrologic cycle, and its accurate estimation is important for hydrologic water balance, irrigation management, crop yield simulation, and water resources planning and management. For agricultural crops, ET is often calculated in terms of a short or tall crop reference, such as well-watered, clipped grass (reference crop evapotranspiration, $ET_o$). The Penman-Monteith equation recommended by FAO (FAO 56-PM) has been accepted by researchers and practitioners, as the sole $ET_o$ method. However, its accuracy is contingent on high quality measurements of four meteorological variables, and its use has been limited by incomplete and/or inaccurate input data. Therefore, this study evaluated the applicability of Backpropagation Neural Network (BPNN) model for estimating $ET_o$ from less meteorological data than required by the FAO 56-PM. A total of six meteorological inputs, minimum temperature, average temperature, maximum temperature, relative humidity, wind speed and solar radiation, were divided into a series of input groups (a combination of one, two, three, four, five and six variables) and each combination of different meteorological dataset was evaluated for its level of accuracy in estimating $ET_o$. The overall findings of this study indicated that $ET_o$ could be reasonably estimated using less than all six meteorological data using BPNN. In addition, it was shown that the proper choice of neural network architecture could not only minimize the computational error, but also maximize the relationship between dependent and independent variables. The findings of this study would be of use in instances where data availability and/or accuracy are limited.

• Korean Journal of Plant Resources
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• v.12 no.4
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• pp.312-323
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• 1999

External morphology, principal component analysis, cluster analysis, and vegetation were investigated to understand the taxonomic relationships and native environmental characters of Megaleranthis saniculifolia populations in four different habitats. Morphological characters such as calyx length and width, calyx index, presence or absence of serrate in calyx lobe, length of peduncle, branch of peduncle and fruit characters were useful for the identification of four different habitats. But, characters of plant height, bract and seed in four habitats were similar. The results obtained based on the principal component(PC) analysis of treated 96 OTU were divided into two groups by PC 1, 2, 3, and the sums of contributions for the total variance were 66.79%(PC1 31.3%, PC2 20.7%, PC3 15.8%, respectively), and only Mt. Taeki population was distinctly different from populations of other three habitats. In cluster analysis based on average linkage cluster analysis and Ward's method, there were similarities in the composition of clustered taxa, and each populations were not identified. Importance value by relative coverage and frequency appeared in M. saniculifolia(50.81%), Aruncus dioicus(12.64%), Corydalus turtschanovii(11.62%), Veratrum oxysepalum(11.45%), Anemone koraiensis(8.96%), Meehania urticifolia(8.76%), Filipendula palmata(7.06%), Aconitum pseudo-laeve(5.66%), Pseudostellaria palibiniana(5.45%) and Smilacina japonica(5.25%), respectively. These species were considered to be highly similar with M. saniculifolia. The highest importance value in all investigated sites was M. saniculifolia, but specific composition of high level different from each habitat. Average diversity of species was 1.40, and the highest in Mt. Kwangdeok(1.31), lowest in Mt. Jumbong(1.17). Average soil pH was 5.25 and similar in each habitat. Although the lowest content of K ion, but the highest the EC, water capacity, organic compound, Ca content were found in soil of Mt. Sobaek. Soils in Mt. Kwangdeok had the lowest content of EC, organic compound, Ca. Soils of Mt. Jumbong showed the highest of Mg content, but the lowest of water capacity, $P_2O_5$, and K contents.