• Korean Journal of Ichthyology
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• v.23 no.2
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• pp.87-94
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• 2011

To find the preliminary environmental conditions for a short-time transport of living olive flounder, Paralichthys olivaceus, the stress response and physiological metabolic activity of the cultured fish to feed deprivation and slow temperature descending ($15.8^{\circ}C{\rightarrow}13.3^{\circ}C$) were monitored for 8 days. The monitored variables were the plasma alanine aminotransferase (ALT), aspartate aminotransferase (AST), glucose (GLU), total protein (TP), electrolytes ($Na^+$, $K^+$, $Cl^-$) and thyroid hormones ($TT_4$, $TT_3$, $FT_4$ and $FT_3$). In food deprivation experiment for 8 days, we did not find any statistical change of level in AST, ALT and electrolytes ($Na^+$, $K^+$, $Cl^-$), but found a significant decrease in TP and GLU. In thyroid hormones, the levels of four hormones in plasma were all showing a tendency to decrease. Especially, $FT_4$ and $TT_3$ were significantly decreased, indicating a withering of physiologic activity. In the temperature test, although no any significant change in AST, TP and electrolytes ($Na^+$, $K^+$, $Cl^-$), we observed a significant decrease of ALT and GLU following to temperature descending from $15.8^{\circ}C$ to $13.3^{\circ}C$ (P<0.05). In the levels of thyroid hormones, any significant change was not observed for experimental period. We conclude that the stress response and physiological activity of olive flounder were more influenced by feed deprivation than slow temperature descending at a transport of living fish, and plasma GLU appears to be sensitive factor to physiological metabolic activity, indicating that it could be used as a monitering mark or index for a health inspection of the fish.

• Korean Journal of Plant Resources
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• v.25 no.1
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• pp.156-168
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• 2012

Chrysanthemum is a cut flower species that normally lasts for 1 to 2 weeks, in some cases 3-4 weeks. This has been attributed to low ethylene production during senescence. Reduction in cut flower quality has been attributed to the formation of air embolisms that partially or completely blocks the water transport from the vase solution to the rest of the cut flower stem, increasing hydraulic resistance which may cause severe water stress, yellowing, wilting of leaf, and chlorophyll degradation. Standard type chrysanthemum can be harvested when buds were still tightly closed and then fully opened with the simple bud-opening solution. Standard type chrysanthemum can also be harvested when the minimum size of the inflorescence is about 5-6 cm bud which opened into the first flower full-sized flower. While spray varieties can be harvested when 2-4 most mature flowers have opened (40% opening). Cut flowers are sorted by stem length, weight, condition, and so on. Standard chrysanthemum is 80 cm length for standard type and 70cm for spray type. Pre-treatment with a STS, plant regulator such as GA, BA, 1-MCP, chrysal, germicide, and sucrose, significantly improved the vase life and quality of cut flowers. It is well established that vase solutions containing sugar can improve the vase life of cut chrysanthemum. Chrysanthemum is normally packed in standard horizontal fiberboard boxes. Chrysanthemum should normally be stored at $5{\sim}7^{\circ}C$. Precooling resulted in reduction in respiration, decomposition, and transpiration activities as well as decoloration retardation. There was significant difference between "wet" storage in 3 weeks and "dry" storage in 2 weeks. In separate pulsing solution trials, various germicides were tested, as well as PGRs to maintain the green color of leaves and turgidity. Prolonging vase life was attained with the application of optimal solution such as HQS, $AgNO_3$, GA, BA and sucrose. This also retarded senescence in leaves of cut flower stems. Fresh cut chrysanthemum can be transported using a refrigerated van with $5{\sim}7^{\circ}C$. Increasing consumption and usage of cut chrysanthemum of various cultivars would require efficient transport system, and effective information exchange among producer, wholesaler, and consumer.

• Journal of the Korean Geographical Society
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• v.38 no.2
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• pp.184-205
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• 2003

Sustainable Development(SD) is an important concept for the future of the coastal area, and for development of fishing villages. Since 1992 UN Conference on Environment and Development in Rio de Janeiro many governments and local authorities throughout the world have been engaged in preparing and implementing $\ulcorner$Agenda 21$\lrcorner$. Many projects which previously would have been identified as environmental protection are now presented under the banner of sustainable development. Integrated Coastal Management (ICM) is an extension of sustainable development. ICM was presented as a framework for resolution of coastal use conflicts. The aim of the present paper is to assess sustainable development potential of fishing villages in Cheonsu Bay Region according to implementation of ICM. Cheonsu Bay Region was known as one of the productive fishing grounds and Cheonsu Bay Region preserved unique characteristics of traditional fishing villages. But this region is now experiencing many changes through the massive reclamation projects like Seosan A B Project. After a brief overview of concepts and history of SD and ICM, the reclamation process and its impacts on both fishery and fishing communities in Cheonsu Bay Region are discussed. According to their changing environmental and socio-economic characteristics after the reclamation, ca 35 representative coastal villages in this region can be classified into 5 types. Many coastal villages shows diversity in their economic activities, as tourism and recreation function becomes more and more important in this region. In present-day Cheonsu Bay Region, it is possible to differentiate fishing village cooperatives(FVO) with high potential of sustainable fishery development, FVOs with medium potential, FVOs with low potential on the basis of 14 selected indicators.

• Korean Journal of Microbiology
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• v.53 no.2
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• pp.83-96
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• 2017

A constructed sea stream in Yeongdo, Busan, Republic of Korea is mostly static due to the lifted stream bed and tidal characters, and receives domestic wastewater nearby, causing a consistent odor production and water quality degradation. Bioaugmentation of a microbial consortium was proposed as an effective and economical restoration technology to restore the polluted stream. The microbial consortium activated on site was augmented on a periodic basis (7~10 days) into the most polluted site (Site 2) which was chosen considering the pollution level and tidal movement. Physicochemical parameters of water qualities were monitored including pH, temperature, DO, ORP, SS, COD, T-N, and T-P. COD and microbial community analyses of the sediments were also performed. A significant reduction in SS, COD, T-N, and COD (sediment) at Site 2 occurred showing their removal rates 51%, 58% and 27% and 35%, respectively, in 13 months while T-P increased by 47%. In most of the test sites, population densities of sulfate reducing bacterial (SRB) groups (Desulfobacteraceae_uc_s, Desulfobacterales_uc_s, Desulfuromonadaceae_uc_s, Desulfuromonas_g1_uc, and Desulfobacter postgatei) and Anaerolinaeles was observed to generally decrease after the bioaugmentation while those of Gamma-proteobacteria (NOR5-6B_s and NOR5-6A_s), Bacteroidales_uc_s, and Flavobacteriales_uc_s appeared to generally increase. Aerobic microbial communities (Flavobacteriaceae_uc_s) were dominant in St. 4 that showed the highest level of DO and least level of COD. These microbial communities could be used as an indicator organism to monitor the restoration process. The alpha diversity indices (OTUs, Chao1, and Shannon) of microbial communities generally decreased after the augmentation. Fast uniFrac analysis of all the samples of different sites and dates showed that there was a similarity in the microbial community structures regardless of samples as the augmentation advanced in comparison with before- and early bioaugmentation event, indicating occurrence of changing of the indigenous microbial community structures. It was concluded that the bioaugmentation could improve the polluted water quality and simultaneously change the microbial community structures via their niche changes. This in situ remediation technology will contribute to an eco-friendly and economically cleaning up of polluted streams of brine water and freshwater.

• Korean Journal of Food Science and Technology
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• v.32 no.6
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• pp.1278-1284
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• 2000

The study was performed to elucidate the effects of ethylene-absorbent on the quality of 'Fuyu' persimmon fruits in the MA package. Five persimmons were packed in a MA package film (low density polyethylene, 0.055 mm film thickness), and stored at $-0.5^{\circ}C$ for 60 days. Two persimmons were repacked in a MA package with or without ethylene absorbent $(1\;M\;KMnO_4+zeolite)$ and stored at $-0.5^{\circ}C$. Ten days later, these packages was moved to $2^{\circ}C$ or $25^{\circ}C$ storage room to examine the effect of the ethylene-absorbent on the quality of the fruits. Ethylene removal by enclosed ethylene absorbent in MA packaging reduced the rate of fruit respiration at $25^{\circ}C$, so that $O_2$ and $CO_2$ concentration in packing were maintained higher and lower, respectively, compared to control. These effects were not observed, however, in $2^{\circ}C$ post-storage. Fruit firmness and sugar composition were also influenced by ethylene absorbent, showing more delayed flesh softening and higher sucrose concentration in ethylene absorbent treated fruits than control. But ethylene-absorbent treatment lowered glucose and fructose concentration. That shows that ethylene could influence on sugar composition by inhibiting sucrose inversion to glucose and fructose. The production of ethanol and acetaldehyde was reduced by ethylene removal, but the effect was not so high as other quality indices.

• Korean Journal of Soil Science and Fertilizer
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• v.28 no.2
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• pp.135-144
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• 1995

Understanding on nutrient solute movement during the course of freezing and thawing was attempted through laboratory and field obsevations. Small sectioned tubes with 5cm inner diameter, 0.2cm thick and 1cm long were connected to 30cm long soil columns for laboratory study. The columns were filled with soil, and treated with 20mmol/kg $KNO_3$ for upper 5cm. The upper end was set in the freezing section, and the lower end was set in the refrigerating section of a refrigerator. Temperature was controlled at $-7({\pm}1)^{\circ}C$ and $1.5({\pm}1)^{\circ}C$, respectively. After top 5cm soil was frozen, the columns were sectioned, and analyzed for $NO_3^-$, $NH_4^+$ and $K^+$. For field study, the 20cm inner diameter and lm long soil columns were installed in Chuncheon and Daegwanryung, where the altitude was 74m and 840m, respectively. The soils used were silt loam and clay loam. The top 20cm soils were treated with 50mmol/kg as $KNO_3$. The soil columns were taken during winter freezing and after thawing. By laboratiry study, upward movement of $NO_3^-$ and $K^+$ during the course of freezing was confirmed. The upward movement of $K^+$ was, however, one fifth to one tenth of $NO_3^-$. The upward movement of inorganic nitrogen as well as laboratory during the course of freezing, but large amount of nitrogen was lost from the profile after thawing in early spring. Leached nitrogen from the upper 20cm to lower part was 17 to 24 percents. The maximum depth of leaching during the experiment was 50cm for all soils. The net loss of inorganic nitrogen from the whole profile ranged 8.7 to 39.5 percents. The net loss was greater in Daegwanryung where temperature was lower and snowfall was larger than Chuncheon, and the loss was greater from the silt loam soil than clay loam soil of which percolation rate was small. The results implied that reasons for nitrogen loss during the winter might include surface washing by snow melt as well as leaching and denitrification.

• Korean Journal of Heritage: History & Science
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• v.37
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• pp.327-348
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• 2004

In this study, after analyzing several local climate characteristics of South Korea, I validated distribution, invasion, foraging, underground activities, attack season as ecological characteristics and also temperature, relative humidity, and tree species as preference characteristics of Korean termites (Reticulitermes speratus kyushuensis Morimoto). Especially, southern part of the Korean peninsula is a suitable area for inhabitation and motion of termites holding same ecological characteristic like R. speratus kyushuensis. Busan is a neighboring district at field distribution north limiting temperature of Coptotermes formosanus Shiraki and Chuncheon is a passing area through the Korean Peninsula of field distribution north limiting temperature of Reticulitermes speratus Kolbe. The termite attack of wood devices was about 34.5% for 3 years in the forest of Jongmyo. Although the attack rate of termite increased each year, the detection rate decreased and the missing rate was high by degrees. I confirmed a foraging habits which is a part of termite colony was a role of continuous decomposition and another was a role of new food hunt as experimental results. The foraging termites were found under ground at Jongmyo in Seoul from April to November in the 2001 and the most active period was on July and August. The termite invasion rate of bait station increased in every monitoring. Through the increasing attack rate of bait station during 2nd monitoring (November, 2000) and 3rd monitoring(March, 2001), I confirmed that termites moved into the deep underground in winter, and were working continuously to forage. R. speratus kyushuensis inhabiting at the Korean Peninsula is a species which has food consumption rate with higher temperature. The termite revealed the greatest amount of food(filter paper) at $30^{\circ}C$(90% RH), but showed increasing death rate at over $32^{\circ}C$. Also, survival rate of this termite was 97% at 84% RH($30^{\circ}C$), but killed 100% at 52% RH($30^{\circ}C$) and 70% RH($30^{\circ}C$). For wood feeding, this was observed the preference in a pine tree(Pinus densiflora) above all others. Survival of termites was high(87%) at a pine tree, but low(13.5%) at a paulownia tree(Paulownia coreana). In this study, I presented the biological characteristic of termite(R. speratus kyushuensis Morimoto) and confirmed the deterioration degree of termite on wooden cultural heritage in Korea. Depending on climate and soil temperature, each area in the southern part of the Korea Peninsula, has some different active period and different distribution of R. speratus kyushensis. With these results, I expect that this report helps to prepare the integrated pest management(IPM) of the termite on wooden cultural heritage in Korea, and it may help to reduce the economical loss from termite damage in Korea.

• Korean Journal of Remote Sensing
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• v.38 no.5_1
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• pp.627-646
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• 2022

Recently, the seriousness of climate change-related problems caused by global warming is growing, and the average temperature is also rising. As a result, it is affecting the environment in which various temperature-sensitive creatures and creatures live, and changes in the ecosystem are also being detected. Seasons are one of the important factors influencing the types, distribution, and growth characteristics of creatures living in the area. Among the most popular and easily recognized plant seasonal phenomena among the indicators of the climate change impact evaluation, the blooming day of flower and the peak day of autumn leaves were modeled. The types of plants used in the modeling were forsythia and cherry trees, which can be seen as representative plants of spring, and maple and ginkgo, which can be seen as representative plants of autumn. Weather data used to perform modeling were temperature, precipitation, and solar radiation observed through the ASOS Observatory of the Korea Meteorological Administration. As satellite data, MODIS NDVI was used for modeling, and it has a correlation coefficient of about -0.2 for the flowering date and 0.3 for the autumn leaves peak date. As the model used, the model was established using multiple regression models, which are linear models, and Random Forest, which are nonlinear models. In addition, the predicted values estimated by each model were expressed as isopleth maps using spatial interpolation techniques to express the trend of plant seasonal changes from 2003 to 2020. It is believed that using NDVI with high spatio-temporal resolution in the future will increase the accuracy of plant phenology modeling.

• Journal of Internet Computing and Services
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• v.25 no.4
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• pp.65-72
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• 2024

To faithfully represent the intention of the work in the exhibition space, lighting that provides high color reproduction like natural light is required. Thus, many lighting technologies have been introduced to improve CRI, but most of them only evaluated the general color rendering index (CRI Ra), which considers eight pastel colors. Natural light provides excellent color rendering performance for all colors, including red and blue, expressed by color rendering index of R9 and R12, but most artificial lighting has the problem that color rendering performance such as R9 and R12 is significantly lower than that of natural light. Recently, lighting technology that provides CRI at the level of natural light is required to realistically express the colors of works including primary colors but related research is very insufficient. Therefore this paper proposes exhibition hall lighting that fulfills CRI with a focus on CRI Ra, R9, and R12 based on the characteristics of natural light. First reinforcement wavelength bands for improving R9 and R12 are selected through analysis of the actual measurement SPD of natural and artificial lighting. Afterward virtual SPDs with a peak wavelength within the reinforcement wavelength band are created and then SPD combination conditions that satisfy CRI Ra≥95, R9, and R12≥90 are derived through combination simulation with a commercial LED light source. Through this, after specifying two types of light sources with 405,630nm peak wavelength that had the greatest impact on the improvement of R9 and R12, the exhibition hall lighting applied with two W/C White LEDs is designed and a control Index DB of the lighting is constructed. Afterward experiments with the proposed method showed that it was possible to achieve high CRI at the level of natural light with average CRI Ra 96.5, R9 96.2, and R12 94.0 under the conditions of illuminance (300-1,000 Lux) and color temperature (3,000-5,000K).

• Journal of the Korean Wood Science and Technology
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• v.13 no.1
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• pp.19-62
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• 1985

This study was performed to investigate: (i) the bending processing properties of silk worm oak (Quercus acutissima Carr.) and Korean red pine (Pinus densiflora S. et Z.) by boiling and steaming treatments; (ii) the effects of interrelated factors - sapwood and heartwood, annual ring placement, softening temperature and time, moisture content. and wood defects on bending processing properties; (iii) the changing rates of bending radii after release from a tension strap, and (iv) the improving methods of bending process by treatment with chemicals. The size of specimens tested was $15{\times}15{\times}350mm$ for boiling and steaming treatments and $5{\times}10{\times}200mm$ for treatments with chemicals. The specimens were green for boiling treatments and dried to 15 percent for steaming treatments. The specimens for treatments with chemicals were soaked in saturated urea solution, 35 percent formaldehyde solution, 25 percent polyethylene glycol -400 solution, and 25 percent ammonium hydroxide solution for 5 days and immediately followed the bending process, respectively. The results obtained were as follows: 1. The internal temperature of silk worm oak and Korean red pine by boiling and steaming time was raised slowly to $30^{\circ}C$ but rapidly from $30^{\circ}C$ to $80-90^{\circ}C$ and then slowly from $80-90^{\circ}C$ to $100^{\circ}C$. 2. The softening time required to the final temperature was directly proportional to the thickness of specimen. The time required from $25^{\circ}C$ to $100^{\circ}C$ for 15mm-squared specimen was 9.6-11.2 minutes in silk worm oak and 7.6-8.1 minutes in Korean red pine. 3. The moisture content (M.C.) of specimen by steaming time was increased rapidly first 4 minutes in the both species, and moderately from 4 to 20 minutes and then slowly and constantly in silk worm oak, and moderately from 4 to 15 minutes and then slowly and constantly in Korean red pine. The M.C. of 15mm-squared specimen in 50 minutes of steaming was increased to 18.0 percent in the oak and 22.4 percent in the pine from the initial conditioned M.C. of 15 percent The rate of moisture adsorption measured was therefore faster in the pine than in the oak. 4. The mechanical properties of the both species were decreased significantly with the increase of boiling rime. The decrement by the boiling treatment for 60 minutes was measured to 36.6-45.0 percent in compressive strength, 12.5-17.5 percent in tensile strength, 31.6-40.9 percent in modulus of rupture, and 23.3-34.6 percent in modulus of elasticity. 5. The minimum bending radius (M.B.R.) of sapwood and heartwood was 60-80 mm and 90 mm in silk worm oak, and 260 - 300 mm and 280 - 300 mm in Korean red pine, respectively. Therefore, the both species showed better bending processing properties in sapwood than in heartwood. 6. The M.B.R. of edge-grained and flat-grained specimen in suk worm oak was 60-80 mm, but the M.B.R. in Korean red pine was 240-280 mm and 260-360 mm, respectively. Comparing the M.B.R. of edge-grained with flat-grained specimen, in the pine the edge-grained showed better bending processing property than the flat-grained. 7. The bending processing properties of the both species were improved by the rising of softening temperature from $40^{\circ}C$ to $100^{\circ}C$. The minimum softening temperature for bending was $90^{\circ}C$ in silk worm oak and $80^{\circ}C$ in Korean red pine, and the dependency of softening temperature for bending was therefore higher in the oak than in the pine. 8. The bending processing properties of the both species were improved by the increase of softening time as well as temperature, but even after the internal temperature of specimen reaching to the final temperature, somewhat prolonged softening was required to obtain the best plastic conditions. The minimum softening time for bending of 15 mm-squared silk worm oak and Korean red pine specimen was 15 and 10 minutes in the boiling treatment, and 30 and 20 minutes in the steaming treatment, respectively. 9. The optimum M.C. for bending of silk worm oak was 20 percent, and the M.C. above fiber saturation point rather degraded the bending processing property, whereas the optimum M.C. of Korean red pine needed to be above 30 percent. 10. The bending works in the optimum conditions obtained as seen in Table 24 showed that the M.B.R. of silk worm oak and Korean red pine was 80 mm and 240 mm in the boiling treatment, and 50 mm and 280 mm in the steaming treatment, respectively. Therefore, the bending processing property of the oak was better in the steaming than in the boiling treatment, but that of the pine better in the boiling than in the steaming treatment. 11. In the bending without a tension strap, the radio r/t of the minimum bending radius t to the thickness t of silk worm oak and Korean red pine specimen amounted to 16.0 and 21.3 in the boiling treatment, and 17.3 and 24.0 in the steaming treatment, respectively. But in the bending with a tension strap, the r/t of the oak and the pine specimen decreased to 5.3 and 16.0 in t he boiling treatment, and 3.3 and 18.7 in the steaming treatment, respectively. Therefore, the bending processing properties of the both species were significantly improved by the strap. 12. The effect of pin knot on the degradation of bending processing property was very severe in silk worm oak by side, e.g. 90 percent of the oak specimens with pin knot on the concave side were ruptured when bent to a 100 mm radius but only 10 percent of the other specimens with pin knot on the convex side were ruptured. 13. The changing rate in the bending radius of specimen bent to a 300 mm radius after 30 days of exposure to room temperature conditions was measured to 4.0-10.3 percent in the boiling treatment and 13,0-15.0 percent in the steaming treatment. Therefore, the degree of spring back after release was higher in the steaming than in the boiling treatment. And the changing rate of moisture-proofing treated specimen by expoxy resin coating was only -1.0.0 percent. 14. Formaldehyde, 35 percent solution, and 25 percent polyethylene glycol-400 solution found no effect on the plasticization of the both species, but saturated urea solution and 25 percent ammonium hydroxide solution found significant effect in comparison to non-treated specimen. But the effect of the treatment with chemicals alone was inferior to that of the steaming treatment, and the steaming treatment after the treatment with chemicals improved 10-24 percent over the bending processing property of steam-bent specimen. 15. Three plasticity coefficients - load-strain coefficient, strain coefficient, and energy coefficient - were evaluated to be appropriate for the index of bending processing property because the coefficients had highly significant correlation with the bending radius. The fitness of the coefficients as the index was good at load-strain coefficient, energy coefficient, and strain coefficient, in order.