• Journal of environmental and Sanitary engineering
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• v.7 no.1
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• pp.87-94
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• 1992

In order to investigate the content of heavy metals in soil according to vertical profiles, 72 soil samples were collected from 4 sampling sites : Ulchiro-2 ga, Dugdo, Sungnaedong, and Amsa- dong. The content of mercury was measured by a mercury analyzer and those of lead, copper and zinc were measured by an atomic absorption spectrophotometer. From the results of this study, it was shown that the content of heavy metals decreased gradually from the surface soil to the 2 m- depth soil. But, there was no difference in the contents of the heavy metals in the 3m, the 4m and the 5m-depth soil.

• Wind and Structures
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• v.26 no.6
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• pp.343-354
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• 2018

A realistic FEM structural model is developed to predict the behavior, load transfer, force distribution and performance of a riverine platform under earthquake and environmental loads. The interaction between the transfer plate and the piles supporting the platform is investigated. Transfer plate structures have the ability to redistribute the loads from the superstructure above to piles group below, to provide safe transits of loads to piles group and thus to the soil, without failure of soil or structural elements. The distribution of piles affects the distribution of stress on both soil and platform. A materially nonlinear earthquake response spectrum analysis was performed on this riverine platform subjected to earthquake and environmental loads. A fixed connection between the piles and the platform is better in the design of the piles and the prospect of piles collapse is low while a hinged connection makes the prospect of damage high because of the larger displacements. A fixed connection between the piles and the platform is the most demanding case in the design of the platform slab (transfer plate) because of the high stress values developed.

• Journal of The Korean Society of Agricultural Engineers
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• v.54 no.6
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• pp.77-87
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• 2012

Recently, Load and Resistance Factor Design (LRFD) based on reliability analysis has become a global trend for economical and rational design. In order to implement the LRFD, quantification of uncertainty for load and resistance should be done. The reliability of result relies on input variable, and therefore, it is important to obtain exact uncertainty properties of load and resistance. Since soil stress is the main reason causing the settlement or deformation of ground and load on the underground structure, it is essential to clarify the uncertainty of soil stress distribution for accurately predict the uncertainty of load in LRFD. In this study, laboratory model test on silty sand bed under probabilistic load is performed to observe propagation of upper load uncertainty. The results show that the coefficient of variation (COV) of soil stress are varied depending on location due to non-linear relationship between upper load increment and soil pressure increment. In addition, when the load uncertainty is transmitted through ground, COV is decreased by damping effect.

• The Korean Journal of Community Living Science
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• v.23 no.4
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• pp.411-418
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• 2012

Phthalates and di-2-ethylhexyladipate are both widely used as industrial chemicals and exposure high levels over long periods of time can cause toxicity, estrogenic responses and endocrine disruption properties in both humans and animals. So far, their global monitoring in environmental matrices has been performed continuously. A developed method, including modified SPEED'98 (Japan Environment Agency) and USEPA was established for simple and rapid determination of phthalates and di-2-ethylhexyladipate in various matrices. This method was applied to explore the distribution levels in domestic environmental media such as water, soil and sediment. Eight phthalates (DEP(di-ethyl), DEHP(di-[2-ethyl-hexyl]), DprP (di-propyl), DBP(di-n-butyl), DPP(di-n-pentyl), DHP(di-n-hexyl), DCHP(di-cyclohexyl), BBP(butyl benzyl) and Adipate (di-2-ethylhexyl adipate) were investigated by seasonal sampling(spring, autumn) at 24 domestic sites. Phthalates and adipate were not detected in water samples and DEP, DBP, and DEHP were mainly detected in soil and sediment samples. The concentrations of DEP and DBP excluding DEHP in spring were higher in soil than those of sediment. Total concentrations of phthalates were significantly decreased in autumn for both soil and sediment.

• Korean journal of applied entomology
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• v.33 no.3
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• pp.153-158
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• 1994

Vegetation rather than soil types, is the predominant factor in determining density and distribution of Dreponotermes tarnminensis (Hill) mounds within the Durokoppin Nature Reserve m Westem Austral~an wheatbelt D tomminensis mounds reach the hlghest densities m Woodland (dominated by Eucalyptus cap~llosa) and Casuarina (dominated by Allocasuarino campestris) vegetation assoc~ations. There appears to be no influence of soil type on mound dishibut~on. although higher mound densities tend to be found on the Booraan soil type.

• Mycobiology
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• v.31 no.2
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• pp.61-67
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• 2003

The mycobiota of the sandy soil of Egyptian beaches was investigated in thirty six sand samples collected from nine different localities in Egypt. The filamentous fungi were identified and assigned to thirty one genera and fifty one species. Greater populations as well as a wider spectrum range of fungal genera and species were obtained in sandy soil of Alexandria beach while Balteem beach was the poorest one. The total count of the genus or species was not depended upon cases of isolation. Most of the genera detected belonged to the Deuteromycotina with fewer proportions belonging to the Ascomycotina and Zygomycotina. The genera of highest incidence and their respective numbers of species were: Penicillium(35.72%, 6 species) and Aspergillus(30.28%, 16 species). The species which showed the highest incidence in all cases was P chrysogenum, followed by P citrinum, A. flavus, Chaetomium murorum and Trichoderma viride. A few number of other genera and species were also detected.

• The Korean Journal of Ecology
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• v.13 no.1
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• pp.25-32
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• 1990

The vertical distribution and seasonal fluctuation of soil microarthropods in the forests with different flora were investigated in this study. soil micrarthropods were concentrated as much as 71.8% in the first layer subsoil (0-5cm), 22.3% in the second layer subsoil (5-10cm), and 5.9% in the third layer subsoil (10-15cm) in the decreasing order. The population density in the first layer decreased slightly in winter while that of the second layer increased. However, the density in the first layer bounced back in the following spring. Seasonal fluctuations of population density were revealed "Two peak-Two valley type", that is, the densities were high in fall and spring, and low in winter and summer.nd summer.

• Korean Journal of Soil Science and Fertilizer
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• v.26 no.4
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• pp.284-288
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• 1993

Tow Kinds of Soils, vertisol and alfisol, were selected and analyzed pore space distribution(PSD) by mercury intrusion method and soil water potential after freeze-drying from different water conditions, such as 0.033MPa, 1.5MPa and ovendry. The PSD values measured by mercury intrusion method were higher in large pores than the values from soil water potential. Also, there were big differences of PSD by the changes of the water content befor freeze-drying.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2003.11a
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• pp.113-118
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• 2003

An investigation has been carried out on collision-induced dissociation (CID) in the development of an analytical protocol for the determination of polycyclic aromatic hydrocarbons (PARs) by ion trap tandem mass spectrometry. Two different considerations were used to choose the optimal CID conditions for complex matrix environmental samples, namely, to determine the highest signal-to-noise (SIN) ratio and the other to eliminate the background interferences originated from complex matrix samples. The PAR content of agricultural soil was measured to estimate overall distribution of PAR in throughout the country, we collected and analyzed 226 soil samples from paddy and upland soil. The average content of total PAR in all samples was 236 ${\mu}g$ $kg^{-1}$, and the range was from 23.3 to 2, 834 ${\mu}g$ $kg^{-1}$. The overall distribution of PAR was found to be closely related to the pollution sources, the size of city and the type of industry.

• Korean Journal Plant Pathology
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• v.14 no.6
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• pp.710-713
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• 1998

Spatial distribution in soil and seasonal population changes of Pasteuria nishizawae first found in Korea from soybean cyst nematode were studied. P. nishizawae infested in 61% of areas in a soybean field; in an average, about 0.3% of 46 cysts and 17.6% of 9 juveniles per 100 g soil were infested with the bacterium. The highest percentages of spore-attached nematodes were found in July (75%) and between soil depth of 11~20 cm. The number of spores per juvenile was positively correlated with the percentage of juveniles with spores (r=0.4203; P＜0.0133), but negatively correlated with the number of juveniles in soil (r=-0.3499; P＜0.042). P. nishizawae completed its life cycle in cyst and produced 1.7$\times$105 spores per cyst.