• Korean Journal of Soil Science and Fertilizer
• /
• v.18 no.2
• /
• pp.194-200
• /
• 1985

To find out the relationships between the changes of soil chemical properties due to submergence and paddy rice yield, a laboratory and 9 field experiments on 9 soil series were carried out. From the field experiments, relative yields of no fertilizer yield to maximum yield were widely distrbuted from 54 to 76, although the correlation between no fertilizer yields and maximum yields was significant. Among the chemical ingredients of submerged soil, $NH_4-N$ only showed significant correlation with no fertilizer yields. From the laboratory experiments, pH were much increased in the soils high in no fertilizer yield than the others. There were no significant correlation between $NH_4-N$ contents of submerged soils and organic matters of dry soils. Soils low in available $P_2O_5$, low in organic matter, and high in clay of dry soil were negligible in increments of available $P_2O_5$ due to submergence, and efficiency of phosphorous fertilizer in those soils were remarkable. Soils extremely high in available $SiO_2$ of dry sail decreased in available $SiO_2$ due to submergence.

• Journal of the Korean Society of Marine Environment & Safety
• /
• v.26 no.2
• /
• pp.156-162
• /
• 2020

Since the early 20th century, there have been reviews and legislations regarding the legal status of the Government ships operated for non-commercial purposes. In particular, as criticized in the absolute theory of immunity in conventional international law, the sovereign immunity theory has become more vital as a restrictive theory for immunity. As per the customary international law and international law of the sea, non-commercial government vessels, including warships, are provided with sovereign immunity on the sea. National universities of Korea have built and operated training ships and survey ships for educational purposes, such as training high-grade mariners and fishing practices. These training ships sail not only on the national maritime jurisdictions but also on the maritime jurisdictions of other States and the high sea. Therefore, clarifying the legal status of national university training ships is one of the important factors in international navigation according to international law. However, it is not easy to answer the question of the legal status of the training ship. Hence, this article analyzes the parameters that define the Government ship operated for non-commercial purposes and examines whether national university training ships are in line with the relevant criterion. Furthermore, the article analyzes the scope of sovereign immunity in conventional international law and international conventions and identifies the scope of sovereign immunity enjoyed by the national university training ships according to international law.

• Journal of Navigation and Port Research
• /
• v.34 no.8
• /
• pp.603-607
• /
• 2010

The LORAN system had been used widely and it was an essential navigation aid for ships in the ocean until the GPS is adopted actively. In particular, it was essential functionality for the ships to sail the oceans. According to the advancement of industry, however, the current accuracy of traditional Loran is insufficient for the utilization of harbour approach, land navigation, and the field of survey and timing. Therefore it is necessary that the study on the improvement of the positioning accuracy of Loran. The one of the improving methods is to measure and compensate the propagation time delay between the transmitter and user's receiver, which is called as additional secondary factor (ASF). In this study, we measured the ASF between the Pohang master transmitting station (9930M) and four points where locate within 33 km apart from the transmitting station, using the measuring technique of the absolute time delay without a time of coincidence (TOC) table. As the result of measurement, the ranging error caused by the propagation delay was about 210 m at 33 km, however it can be reduced up to 40 m with ASF compensation.

• Journal of the Korean Society of Marine Environment & Safety
• /
• v.25 no.6
• /
• pp.642-648
• /
• 2019

Vessels sail according to the COLREG to prevent a collision. However, it is difficult to apply COLREG under special situation as heavy traffic, at this time personal skills of the operator are required. In this case, traffic control is required through the maritime traffic monitoring system. Therefore, maritime traffic management is globally implemented by VTS. In this system, VTS of icer uses the VTS system to assess risks and recommends possible safety operation to vessels with radio systems. This study considers that the risk analysis method with AI (Artificial Intelligence) technology from the operator's aspect. In addition, the research explains the Maritime Traffic Safety Monitoring System, Including AR (Augmented Reality) technology to increase vessel control efficiency. This system is able to predict hazards and risk priorities, and it leads to sequential elimination of dangerous situations. Especially, the hazard situations can be analyzed from operator's perspective of each vessel instead of the VTS officer's aspect, which is more practical than the conventional method. Furthermore, the result of analysis enables to comprehend quantitative hazardous areas and support recommended routes to avoid a collision. As a result, I firmly believe that the system will support to prevent a collision in complex traffic waters. In particular, it could be adopted as a collision prevention system for Maritime Autonomous Surface Ship, which occupies a significant proportion in Maritime 4th industrial revolution.

• Korean journal of applied entomology
• /
• v.10 no.1
• /
• pp.23-30
• /
• 1971

This work was carried out to study the chemical properties, the activity of several enzymes, chemical components and the respiratory intensity of mite galls on the leaves of Lycium chinense MILL. caused by Eriophyes kuke KISHIDA. The activities of catalase and peroxidase were higher in the gall tissue, when compared to the healthy tissue, and were increased as tile gall developed. The activity of phosphorylase of the healthy tissue seemed to be higher than that of the large gall l tissue, considering the competitive inhibition of phosphomonoeoterase and $\beta-amylase$, The activities of invertase and $\beta-amylase$ were about two times higher in the large sail tissue than those of the healthy tissue. The content of the crude protein was $20\%$ higher in the small gall tissue than that of the healthy leave tissue, and decreased as the gall matured. On the other hand, the reducing sugar level was less in the small gall tissue than that of the healthy leaves, but as the gall grew, the content of reducing sugar of the gall tissue was increased. The contents of phosphorus and tannin were increased gradually as the gall matured, and their content showed about two times higher than those of the healthy. The matured gall tissue showed higher $QO_2$ than the healthy tissue. On the other hand, the matured gall tissue presented lower $QCO_2$ than the healthy tissue, and the RQ of the healthy tissue was higher than that of the gall tissue.

• Korean Journal of Environmental Agriculture
• /
• v.19 no.2
• /
• pp.128-133
• /
• 2000

This study was conducted to investigate the adsorptive characteristics with cadmium in different levels of organic matter and lime in soil. And in order to identify the effect of soil ameliorators on cadmium uptake in rice plants, compost and lime were treated. Plants were grown at two soil textures(sandy loam and clay loam) with irrigation water containing $0.01\;mg\;L^{-1}$ of cadmium and treatments of two irrigation systems(intermittent irrigation and continuous submersion). The adsorption capacity of cadmium by soil was increased in proportion to initial concentration of solution, and it was higher at clay soil compared to loamy soil. The adsorption rate of cadmium by soil was increased with increasing the concentration of organic matter and lime in soil, highly increased at the both organic matter and lime treatment. Soil pH was negatively correlated with the cadmium contents of the both shoot and brown rice while Eh was positively correlated with those. In the harvest season, cadmium contents in the both leaves and brown rice were lower in the clay sail plots than sandy soil plots, and the continuous submersion plots were lower than intermittent irrigation plots. Cadmium uptake was highly reduced at the compost and lime mixture plot compared to other treatments among the continuous submersion plots. The cadmium content of shoot was positively correlated with that of brown rice in the harvest season.

• Korean Journal of Soil Science and Fertilizer
• /
• v.30 no.2
• /
• pp.200-207
• /
• 1997

In order to evaluate the soil microbiological characteristics of paddy fields in Korea, surface soils were sampled from 63 sites in different agroclimatic zones before submersion of the fields. The distribution of microorganisms and the microbial diversity indices were examined. Soil microbial populations were generally higher in southern area than in northern area. The colony forming units(cfus) of fluorescence Pseudomonas sp. showed the greatest regional differences, among the microbes investigated. On the topographical differences, the cfus of aerobic bacteria, fluorescence Pseudomonas sp. and Azotobacter sp. maintained high level in coastal plains; and on the sail textural difference, fungus was the highest in clay soil, but Bacillus sp., Azotobacter sp and denitrifiers were the highest in silty clay loam soil at 0.05 probability level based on the multiple range test. The numbers of ammonium oxidizers and Azotobacter sp. were increased with soil pH. Microbial diversity indices of paddy fields which calculated from the percentages of Bacillus sp. fluorescence Pseudomonas sp. Azotobacter sp. denitrifiers, ammonium oxidizers, nitrite oxidizers, actinomycetes and fungus to these total microbial numbers were between 0.109 and 0.661. On the soil textures, the microbial diversity indices of sandy, sandy loam, silty clay loam, clay loam and clay soil were 0.443, 0.427, 0.414, 0.405 and 0.362 respectively.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.19 no.9
• /
• pp.316-325
• /
• 2018

In this paper, to integrate distributed IT resources and manage human resource efficiently as purpose of cost reduction, infrastructure of wind turbine monitoring system have been designed and developed on the basis of SaaS cloud. This infrastructure hierarchize data according to related task and services. Softwares to monitor conditions via the infrastructure are also developed. Softwares are made up of DB design, field measurement, data transmission and monitoring programs. The infrastructure is able to monitor conditions from SCADA data and additional sensors. Total time delay from field measurement to monitoring is defined by modeling of step-wise time delay in condition monitoring algorithms. Since vibration data are acquired by measurements of high resolution, the delay is unavoidable and it is essential information for application of O&M program. Monitoring target is gearbox in wind turbine of MW-class and it is operating for 10 years, which means that accurate monitoring is essential for its efficient O&M in the future. The infrastructure is in operation to deal with the gearbox conditions with high resolution of 50 TB data capacity, annually.

• Korean Journal of Food Science and Technology
• /
• v.39 no.4
• /
• pp.380-385
• /
• 2007

This study was basic research to improve the existing method far distributing just harvested and sail-clad fresh ginseng. The quality of surface-washed fresh ginseng was compared to that of muddy fresh ginseng during storage at 0, 5, 10, and $20^{\circ}C$. After 45 days of storage, there was no difference in weight loss between the washed ginseng and the control at $0^{\circ}C$, but the loss was 46% and 37% lower in the washed than the control at $5^{\circ}C$ and $10^{\circ}C$, respectively. The ginseng stored at $20^{\circ}C$ after washing had less deterioration than the control stored at $10^{\circ}C$ for the same period. The sensory characteristics of the washed ginseng showed better quality scores ranging from 6.8 to 8.2, while the control ranged from 5.7 to 6.9 after 45 days of storage at $10^{\circ}C$. The washed ginseng had less viable cells, mold and yeast, and coliforms at 0.87, 1.55, and 0.95 log units, respectively, compared to the control, and this trend was maintained in the washed ginseng throughout storage.

• Korean Chemical Engineering Research
• /
• v.44 no.2
• /
• pp.149-159
• /
• 2006

This research is a development of useful S/W program for real industry about optimal product scheduling in real plant for manufacturing polymer products. For this, we used a fine model with total amount of losses in weight(ton) as an objective for optimal scheduling and a genetic algorithm for optimization in this factory they manufacture three different products. Major products are A and B but the product which can be process in the period of products change over. They also sells them as a chap product in market. The major products have several types of packing process-bulk, pack for domestic market, pack for export. The demands of product with each packing type are increased, and frequently they failed keep the deadline for sail. Based on realistic production situation, we composed a fine modeling for optimal scheduling. And we also develop a S/W program for optimal scheduling which can be used by non-specialist in scheduling problem. We used a modified genetic algorithm and it gave us a better solution in process. We can have a result of reducing the total amount of losses in weight by half compared with the losses when existing production schedule.