• Resources Recycling
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• v.33 no.3
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• pp.3-11
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• 2024

This study addressed the cost structure of metallurgical plants for vanadium recovery or production, which were previously planned or implemented. Vanadium metallurgy consists of several sub-processes such as such as pretreatment, roasting, leaching, precipitation, and filtration, in order to finally produce vanadium pentoxide. Here, lots of costs should be spent for such plants, in which these costs are largely divided into CAPEX (Capital Expenditure) and OPEX (Operational Expenditure). As a result, the capacities (feed input rates) and vanadium contents are various along the target projects for this study. However, final production rates and grades of vanadium pentoxide showed relatively small differences. In addition, a noticeable correlation is found between capacities and specific operating costs, in that a steadily decreasing trend is described with a non-linear curve with around -0.3 power. Therefore, for the plant capacity below 100,000 tons per year, the specific operating cost rapidly decreases as the capacity increases, whereas the cost remains relatively stable in the range of 0.6 to 1.2 million tons per year of the capacity. From a technical perspective, effective optimization of the metallurgical process plant can be achieved by improving vanadium recovery rate in the pre-treatment and/or roasting-leaching processes. Finally, the results of this study should be updated through future research with on-going field verification and further detailed cost analysis.

• Journal of The Korean Society of Grassland and Forage Science
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• v.32 no.3
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• pp.209-220
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• 2012

Most oats are used for livestock feed in the world. This experiment was conducted at Iksan city of Korea from 2007 to 2008. The objective of this study was to select eminent oat (Avena sativa L.) cultivars with high-yielding and a quality for forage adaptable in each planting seasons. Experimental design was split-plot design with three replications. A split plot design was used with seeding date on the main plots and other treatments fully randomized in sub-plots. A factorial arrangement of treatments included three different ecotypes cultivars, winter type (Sanmhan, Donghan and Chohan), summer type (High-speed, Darkhorse, and Swan), and naked oats near to spring type (Daeyang, Choyang, and Sunyang) and twelve seeding dates (twice a month from March to November). Plant height, dry matter yield, and percent TDN was significantly affected by seeding dates, cultivars, and the interaction of cultivars ${\times}$ seeding dates. There was a decrease in plant height, dry matter yield, and percent total digestible nutrients (TDN) as seeding was delayed from early March to late June and it also from early September to early November. The winter type oat cultivars such as Samhan, Donghan, and Chohan adapted to fall seeding and early summer harvest, while summer type cultivars such as High-speed, Darkhorse, and Swan showed high productivity either to summer seeding and mid-fall harvest or to spring seeding and early summer harvest. Naked type cultivars, Choyang and Daeyang, showed high forage yield by spring and summer seeding except for fall seeding because of cold damage. Summer type oat cultivars such as High-speed, Darkhorse, and Swan can supplement high forage production in spring. TDN yield showd the most at seeding in October 10 (780 kg $10a^{-1}$), followed at seeding in March 23 (627 kg $10a^{-1}$).

• The Journal of Fisheries Business Administration
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• v.26 no.2
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• pp.53-74
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• 1995

The purpose of this paper is to compare China's and Korea's marine fisheries industries in order to present the main features of China's marine fisheries and show the comparative advantages they have in production. The results indicate that China's marine fisheries have the following features. (1) The marine proportion of the fisheries industry economic activity is less than 60%. Fishing is 71.3% of that marine activity. (2) The production trends of marine fisheries history in China can be classified as follows: 1) an early growth period, 2) a deliberation/consolidation period, 3) a second growth period, 4) a third growth period, and 5) a fourth growth period. The growth rate has rapidly increased recently. (3) Fish production is over 70% of marine fishing fisheries, the next major product is crustacea. The production of shellfish occupies over 70% of marine aquaculture, seaweed production however, is only 22% of total marine aquaculture. (4) The licensed area for marine aquaculture in China is 586.3 ha and that area is 5.4 times larger than that of Korea. The allotted area for shellfish aquaculture is 60% of marine aquaculture, production areas of crustaceans occupy 27.3%, fish has 7 1%, and seaweed production only 5.7% of allocated marine aquaculture areas. (5) The proportion of power vessels for marine fisheries of China's total power vessel fleet is around 65%, and the marine fisheries portion of non - powered vessels constitutes only 12%. The highest proportion of power vessels engaged in marine fisheries activities is between 10 tonnes to 100 tonnes. (6) The portion of marine fishery workers of all fishery industry employees is 22%, and 70% of them are full - time workers. Of marine fishery workers, 64% are in the fishing sector, 22%, aquaculture workers, and the number of employees in marine fisheries is increasing every year. The analysis of China's fishery industry in the production competitiveness indicates as follows : (1) The licensed areas in marine aquaculture, number of fishing vessels, number of marine fishing workers in China's fishery industry are much more than those of Korea's. Therefore China is much more competitive than Korea in the quantity of production side. However, licensed areas for seaweed aquaculture are more extensive in Korea than China. In China, the number of power vessels of between 10 tonnes and 100 tonnes, the licensed shellfish aquaculture areas, and the number of fishing workers within the fisheries industry are much more than those of Korea. (2) It is estimated that the licensed areas in marine aquaculture, number of medium sized power vessels, number of marine fishery workers will be increased as the quantity of production factors grow in China. (3) At present, yield per Ha. in marine cultures is very low in China. Therefore it is estimated that aquaculture techniques have only been diffused recently in China. Yield of fish per Ha especially is much lower than that of Korea. So the level of aquaculture techniques seems much lower than that of Korea. (4) China is behind Korea in production technique, however the number of HP per boat in China is lower than that of Korea. Therefore, China is much more competitive than Korea in Costs. (5) Average fish catches per marine fishery worker in China is only 1/3 that of Korea's, and average marine aquaculture production in China is only 1/2 that of Korea. Therefore we can say Korea is more competitive than China in efficiency. The average income of marine fishery workers in China is higher that that of other Chinese industries. However, the competitiveness of the fisheries industry in China will be increased as more capital is invested and advanced techniques are developed.

• Journal of Korean Society of Forest Science
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• v.106 no.4
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• pp.388-396
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• 2017

This study was carried out to determine effects of bamboo species on the distribution of nutrients in aboveground biomass of Phyllostachys bambusoides and Phyllostachys nigra var. nenosis, Damyanggun, Korea. The study site was established around 40-year-ago to produce bamboo culm and edible shoot production. Total 28 bamboos (14 P. bambusoides and 14 P. nigra var. nenosis) were cut to measure nutrient concentration of each bamboo component, such as culm, branches and leaf. Magnesium concentration in each bamboo component was significantly higher in the P. bambusoides than in the P. nigra var. nenosis. Nutrient concentrations except for calcium were significantly higher in the current-year-old bamboos than in the > 1-year-old bamboos. The nutrient concentration in leaf was generally highest in carbon, followed by potassium or nitrogen, phosphorus, calcium or magnesium. Total nutrient content in each bamboo component was significantly higher in the P. bambusoides than in the P. nigra var. nenosis. The nutrient content of bamboo biomass was the highest in carbon, followed by potassium, nitrogen, phosphorus, magnesium and calcium. The results indicate that P. bambusoides uptakes more nutrients compared with P. nigra var. nenosis during growth development.

• Journal of Conservation Science
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• v.35 no.5
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• pp.453-469
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• 2019

The celadon jar with inscription of 'the Fourth Sunhwa Year' is an important chronology that shows the conditions of production of the early celadon due to the inscription on the bottom including its purpose, application, and the producer. This celadon jar has been restored several times in the past. However, concerns over the structural stability, such as the separation and level differences in the joined cracks, have risen because of the aging of the repair materials, which were subjected to various environmental changes over a long time. By examining the conditions of preservation, the major damage was identified as the '入' shaped crack on the front, the 'V' shaped restored part and the crack on its left side, and the 'J' shaped crack on the back side. In the past, the cracks were found to be joined using a refined lacquer containing camphor, drying oil, rosin, etc. mixed with soil powder. The joint line was repainted with the refined lacquer and covered with gold powder. The missing parts were restored with gypsum and colored with acrylic color. After that, the repair materials were aged and emergency treatment was performed at the National Museum of Korea in 1981. At that time, Cemedine C or Cemedine C mixed with microballoons was used for reinforcing the cracks. Conservation treatment focused on removing the past repair materials and reinforcing the physically fragile parts by joining and restoring them based on the examination of the preservation condition. in addition, the area around the restored part was colored for future exhibition.

• The Korean Journal of Mycology
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• v.45 no.3
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• pp.188-195
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• 2017

Despite the high commercial value of the pine mushroom (Tricholoma matsutake) around the world, its production still depends upon natural harvesting. In recent years, mushroom researchers in Korea and Japan have been successful in artificially cultivating T. matsutake by producing single mushroom through matsutake-infected pine seedlings. In this study, we determined the minimum seedling height required for the survival of matsutake mycelia in the infected pine seedlings in the field. The survival rate of matsutake mycelia in the matsutake-infected pine seedlings was 50% (14) in two years and 71% (10) in one year after their transplantation. The average height at time of transplantation of the matsutake-infected pine seedlings that bore surviving mycelia after transplantation was 25 cm (minimum 12 cm to maximum 40 cm). In conclusion, the matsutake mycelium of matsutake-infected pine seedlings was able to survive in field conditions if the height of the seedling at the time of T. matsutake infection was at least 12 cm. These results suggest that the height of the host plants used in conventional matsutake-infected pine seedling production should be greatly reduced to improve the matsutake cultivation. Therefore, standardization of the seedling height for artificial cultivation of pine mushrooms by the matsutake-infected pine seedling method is suggested.

• Asian-Australasian Journal of Animal Sciences
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• v.20 no.2
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• pp.160-165
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• 2007

Dispersion parameters for the number of piglets born alive were estimated using a repeatability and random regression model. Six sow breeds/lines were included in the analysis: Swedish Landrace, Large White and both crossbred lines between them, German Landrace and their cross with Large White. Fixed part of the model included sow genotype, mating season as month-year interaction, parity and weaning to conception interval as class effects. The age at farrowing was modelled as a quadratic regression nested within parity. The previous lactation length was fitted as a linear regression. Random regressions for parity on Legendre polynomials were included for direct additive genetic, permanent environmental, and common litter environmental effects. Orthogonal Legendre polynomials from the linear to the cubic power were fitted. In the repeatability model estimate of heritability was 0.07, permanent environmental effect as ratio was 0.04, and common litter environmental effect as ratio was 0.01. Estimates of genetic parameters with the random regression model were generally higher than in the repeatability model, except for the common litter environmental effect. Estimates of heritability ranged from 0.06 to 0.10. Permanent environmental effect as a ratio increased along a trajectory from 0.03 to 0.11. Magnitudes of common litter effect were small (around 0.01). The eigenvalues of covariance functions showed that between 7 and 8 % of genetic variability was explained by individual genetic curves of sows. This proportion was mainly covered by linear and quadratic coefficients. Results suggest that the random regression model could be used for genetic analysis of litter size.

• Proceedings of the Korean Vacuum Society Conference
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• 2016.02a
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• pp.195.1-195.1
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• 2016

Currently, as Plasma application is expanded to the industrial and medical industrial, low temperature plasma applications became important. Especially in medical and biology, many researchers have studied about generated radical species in atmospheric pressure low temperature plasma directly adapted to human body. Therefore, so measurement their plasma parameter is very important work and is widely studied all around world. One of the plasma parameters is electron density and it is closely relative to radical production through the plasma source. some kinds of method to measuring the electron density are Thomson scattering spectroscopy and Millimeter-wave transmission measurement. But most methods have very expensive cost and complex configuration to composed of experiment system. We selected Michelson interferometer system which is very cheap and simple to setting up, so we tried to measuring electron density by laser interferometer with laser beam chopping module for measurement of temporal phase difference in plasma jet. To measuring electron density at atmospheric pressure Ar plasma jet, we obtained the temporal phase shift signal of interferometer. Phase difference of interferometer can occur because of change by refractive index of electron density in plasma jet. The electron density was able to estimate with this phase difference values by using physical formula about refractive index change of external electromagnetic wave in plasma. Our guiding laser used Helium-Neon laser of the centered wavelength of 632 nm. We installed chopper module which can make a 4kHz pulse laser signal at the laser front side. In this experiment, we obtained more exact synchronized phase difference between with and without plasma jet than reported data at last year. Especially, we found the phase difference between time range of discharge current. Electron density is changed from Townsend discharge's electron bombardment, so we observed the phase difference phenomenon and calculated the temporal electron density by using phase shift. In our result, we suggest that the electron density have approximately range between 1014~ 1015 cm-3 in atmospheric pressure Ar plasma jet.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.15 no.4
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• pp.259-268
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• 2003

The damage of water quality like red tide occurs every year inspite of the total load regulation of pollutant inflows from land such as COD, phosphorus and so on around Seto inland sea in Japan. It is attributed to the increase of primary production due to eutrophication. and the rising and settling from the sediment containing nutrient salt. Furthermore, the recent research shows that nutrient salt such as nitrogen and phosphorus, flows into Kii channel from land as well as the Pacific ocean. To investigate the distribution of water quality and flow and residual current in Kitan strait, the field observations were carried out. The field data were obtained a time each season from 1999 to 2002. The results of observations and data of other research institution are used to understand the mechanism of pollution in the strait.

• The Korean Journal of Food And Nutrition
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• v.22 no.2
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• pp.261-271
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• 2009

Deep sea water exists at depths of over 200m under the sea. As no sunlight reaches it, photosynthesis does not take place within it, and it contains no organic matter. In addition, its temperature is maintained at a stable low level throughout the year, so it does not get mixed with the sea water on the surface. It contains a large amount of nutritious salts, whose cleanness is maintained. It is a marine resource that has matured for a long period of time. Research into deep sea water, which started in the 1970s, has been made around the whole world, including the USA and Japan. In Korea, research has been active in this area since 2000. As there has been a good amount of research into industrial applications for deep sea water, since 1993, patents for the relevant technologies have been applied. This paper intends to provide a resource to researchers of deep sea water, by summarizing of all domestic deep sea water-related patents applied with Korean Intellectual Property Office from 1993 to 2008. This research was conducted using a computer and KIPRIS Database owned by the Korea Institute of Patent Information. 'Deep sea water' was used as the search keyword. A total of 222 Korean patents relating to deep sea water have been registered on the basis of IPC. Of these, 126 patents relate to the manufacturing and the treatment of foods, foodstuffs, or non-alcoholic beverages(A23L), while 50 patents relate to the production for medical, dental, or cosmetic purposes(A61K). 38 patents relate to water purification, treatment of wastewater, sewage and sludge (C02F), while 8 patents relate to fishery and farming(A01K). In summary, it was found that studies for the practical use of deep sea water have been conducted in relation to the manufacturing and the treatment of foods, foodstuffs, beverages, and cosmetics.