• Korean Journal of Weed Science
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• v.4 no.2
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• pp.149-153
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• 1984

The growth of Calystegia japonica Choisy as affected by pH, drying, burial, soil moisture and light intensity was determined. Germination of C. japonica rhizome was not affected by pH's ranging from 4.8 to 8.7,while the greatest growth after germination was obtained at pH 5.7. Drying longer than 14 h at $35^{\circ}C$ brought about a significant reduction in percent survival and the subsequent growth of C. japonica. A significant decrease in growth of C. japonica occurred when the rhizome was buried at 0 ㎝ and deeper than 8 cm. The greatest growth was obtained when the soil moisture content reached 40 to 60% of saturated soil. Increasing percent available light resulted in decrease in the plant height, but increase in the root length and dry weight.

• Korean Journal of Soil Science and Fertilizer
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• v.28 no.4
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• pp.340-349
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• 1995

Effects of the zeolite particle size on the soil chemical properties and on rice growth was investigated on the pot with the loamy sand (Sadu series) and silty clay loam(Paju series) soils. All the zeolite treatments brought the increase of unhulled grain yield on the both loamy sand and silty clay loam soils. Unhulled grain yield increased with increasing the amount of zeolite applied and with decreasing the amount of particle size of zeolite applied on both soils. Unhulled grain yield increased significantly by 11.1% (22.79g/head) with 2ton/10a of smaller than $106{\mu}m$ size zeolite on the loamy sand soil and on the silty clay loam soil, yield increased by 9.3% (24.98g/head) with 1.5ton/10a of smaller than $106{\mu}m$ size zeolite. CEC, pH and contents of exchangeable cations of the soil after experiment were raised by increasing the amount of zeolite and also by decreasing the particle size of zeolite at both soil. At the heading stage, the zeolite treatments improved the growth of rice plant compared to control. The nutrient contents(T-N, Ca, Mg, K, Na), except phosphorus, in the rice plant grown on the zeolite treated soils were higher than control plot.

• Structural Engineering and Mechanics
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• v.65 no.5
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• pp.557-572
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• 2018

The academic research works about liquid storage tanks are reviewed for the purpose of providing valuable reference to the engineering practice on their aseismic design. A summary of the performance of tanks during past earthquakes is described in this paper. Next, the seismic response of tanks under unidirectional earthquake is reported, supplemented with the dynamic response under multidirectional motions. Then, researches on the influence of soil-structure interaction are brought out to help modify the seismic design approach of tanks in different areas with variable properties of soils. Afterwards, base isolation systems are reported to demonstrate their effectiveness for the earthquake-resistant design of liquid storage tanks. Further, researches about the liquid-structure interaction are reviewed with description of simplified models and numerical analytical methods, some of which consider the elastic effect of tank walls. Moreover, the liquid sloshing phenomenon on the hydrodynamic behaviors of tanks is presented by various algorithms including grid-based and meshfree method. And then the impact of baffles in changing the dynamic characteristics of the liquid-structure system is raised, which shows the energy dissipation by the vortex motion of liquid. In addition, uplifting effect is given to enhance the understanding on the capacity of unanchored tanks and some assessment of their development. At last, the concluding remarks and the aspects of extended research in the field of liquid storage tanks under seismic loads are provided, emphasizing the thermal stress analysis, the replaceable system for base isolation, the liquid-solid interaction and dynamic responses with stochastic excitations.

• Korean Journal of Soil Science and Fertilizer
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• v.17 no.4
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• pp.314-318
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• 1984

China has made rapid strides in agricultural production during the past few years. Although the absence of any serious climatic disturbances is a contributing factor, implementation of the responsibility system to reward peasant families for their initiatives has been by far the most significant. This has resulted in increased specialization, a greater requirement for technical adivsory services, and a much higher demand for farm equipment and production inputs. The revamped system has brought with it some problems such as differences in income between the most progressive producers and their less successful neighbours and urban workers, a shortage of storage, transport and processing facilities, and a strain on the national treasury to continue to subsidize farm prices. Demand for fertilizers has been increasing at a fast rate, especially for nitrogen. This has led to a serious imbalance in nutrient use which must be corrected if the current momentum in improving crop yields is to be maintained. Following a decade of total stagnation during the Cultural Revolution, agricultural research and education facilities are being strengthened. Younger scientists, many with overseas training, are being placed in key positions. China is still a developing country, and much remains to be done; however, progress in the last decade, and especially in the past five years, has been remarkable.

• Magazine of the Korean Society of Agricultural Engineers
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• v.38 no.5
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• pp.116-124
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• 1996

The purpose of The work described in this paper is to clear up the initial moisture content, specific surface, air drying and freezing-thawing process on liquid limit of clayey soils distributed widely at estuary of three main rivers in the west coast. To this end, a series of tests were conducted on clayey soils samples with natural state and treated state. From the test results, the liquid limit was decreased with decrement of initial moisture content, air drying process, and freezing-thawing cycles and increased with increment of specific surface. The specific surface which influenced on the liquid limit is over $25 m^2$m$^2$/g, and their relationships are well formulated. Air drying process is expected to improve the engineering properties of the soils such the pro-water properties were changed to anti-water proper-ties through lowering of water holding as resulted to incline from A-7-5 to A-5 on the soil classificaction plastic chart. The freezing-thawing process decreased 20% of liquid limit, especially under the first cycle of the behavious, as a result of above mentioned reasons, phase change of soil-water system brought the decrement of specific surface and affected to the liquid limit.

• Journal of Soil and Groundwater Environment
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• v.10 no.3
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• pp.52-63
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• 2005

Korea has recently implemented two m메or policies on organic wastes, including food wastes. One is the Volume-Based waste Fee System (VBWFS). which went effect nationwide in January 1995, and the other is a ban on the landfill of organic wastes, such as food wastes. organic sludge, and animal manure, in accordance with the Waste Management Act. These two policies have brought about remarkable positive effects, including the reduction of organic wastes at source, and the development of technology for recycling food wastes into feed and compost. However, they have caused obstacles to carry out the policy on food wastes, in areas of legal and technological infrastructures for recycling. Therefore, this study intends to find problems of policies for recycling food wastes, and to suggest ways to resolve them.

• International Journal of Highway Engineering
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• v.8 no.1 s.27
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• pp.45-54
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• 2006

The Construction policy of government ever since 1970s have brought the economical growth, but has been causing environmental problems. Most roads were paved either asphalt concrete or portland cement concrete. These types of pavements has caused to rise temperature by making local heat islands in urban during summer time. Recently the wet-mixing solidified soil pavement, a kind of soil-cement, has developed and has been applied to the environment-oriented pavement. The solidified soil wet-mixed is placed on the subgrade along with asphalt concrete and portland cement concrete. Thermistors are laid in these field test pavements. The temperature gradients of these pavements are automatically measured with time. As the results of this test, the equation estimating surface temperature of pavement is proposed by analyzing measured temperature data. It is shown that the temperature change within the surface layer due to the change of air temperature is the greatest in the asphalt mixture and the least in the solidified soil mixture. Since it is proven that this wet-mixing solidified soil pavement emit less radiant heat than other existed pavements. Therefore this type of pavement can be successfully applied to the roads, such as walks, parkways, and bikeways, which are required to be human-friendly and environment-oriented.

• Journal of Life Science
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• v.17 no.7 s.87
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• pp.944-947
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• 2007

Bacillus sp.LPO3 (producing emulsifying substances such as bio-surfactant) was used as a bio-control agent to degrade hydrocarbon (gasoline in oil spilled crop soil). The soil (brought from fertilizer store)was mixed with gasoline-spilled soil (made with Diatomaceous Earth, Sigma.U.S.A). The study was conducted for a period of 13 days, 13 days during which bacterial growth, hydrocarbon degradation and growth parameters of Bacillus sp.LP03 including shoot and root length were studied. We found that the effective of bacterial producing substance might bio-surfactants let the plants survive even more promote the growth of shoot and root length and showed antifungal activity against gray mold. Without the bacteria, they couldn't grow in oil-spilled soil not even survive. According to the results of the above experiments, we can see with following results, hydrocarbon in gasoline was reduced, day by day, then RNA dot blotting was done and it fit the results we had done. Finally, this Bacteria(producing bio-surfactant) were found to have effective bio-control agent for cropping in oil spilled soil and infected by gray mold.

• Korean Journal of Soil Science and Fertilizer
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• v.28 no.2
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• pp.130-134
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• 1995

To investigate the influence of coal fly ash treatment on the heavy metal content in the infilteration water, 12t/10a/year of fly ash(Anthracite and Bituminous) were applicated at two paddy fields of different textured soils, clay loam and sandy loam, for 3 and 2 years, respectively. The infilteration waters were collected 30, 60 and 100cm of soil depth and the heavy metal contents were measured. In the paddy field of clay loam, the content of Zn in the infilteration water were increased with fly ash treatment and increasing soil depth, but it didn't show any significance. In the clay loam soil, successive application of fly ash for 3 years brought to increase Pb, Zn content in the infilteration water, Pb content was the highest at 100cm of soil depth, but the content of others were lower than non-treatment. In the paddy field of sandy loam, successive application of fly ash for 2 years increased Cd, Ni and Mn content in the infilteration water at anthracite ash application, but the contents of other elements were similar or lower than non-treatment.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2015.11a
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• pp.85-86
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• 2015

Recently, As the high rise buildings have been demanded due to the rising current of land price, the permanent drainage method have been applied during and after the construction as a way to reduce the buoyancy acting on the bottoms of the foundations in the basement. This method has brought about the consolidation subsidence of the ground and turned out to be the problems of sinking hole and foundation re-settlement. The representative methods to be used for extending the life cycle of the existing building structure which is tilted by the foundation re-settlement or differential settlement of the foundation can be divided into the building structures reinforcement and soil reinforcement. The purpose of this study is to analyze and present the application example of steel pipe pile method to extend the life cycle of the six -stories building tilted in a soft ground.