• Journal of Plant Biology
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• v.7 no.2
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• pp.1-8
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• 1964

Cha, Jong Whan (Dept. of Biology, Graduate School, Dong Kuk Univ.) The changes of chemical properties of forest soils in dry and wet seasons. Kor. Jour. Bot. VII(2): 1-8, 1964. Soil selected for the present investigation was collected from a mountain of the Forestry Experiment Station of the vicinity of Seoul. The forest communities studied were three forest and a unplanted soils. The soil samples were obtained from each forest type during dry and wet seasons. And these samples were collected from four horizons of all communities respectively. It was showed that exchangeable hydrogen was increased by rainfall, and total exchangeable base decreased in the same way. The content of nitrogen is washed away by rainfall, especially ammonium nitrogen was highly significant between dry and wet season. On the contrary, organic matter and available phosphorus were of no significant difference between dry and wet seasons. The values of pH appeared a different response in dry and wet seasons according to the plant communities. The needle-leaved forest soils showed more acidity than the broad-leaved forest soils, and the least acidity in open places. All nutrients in soil studied gradually decreased down the profiles. According to statistical analyses of the soil components among all soil horizons, total exchangeable bases in wet season indicated only significant at 1%. Exchangeable hydrogen and organic matter of the soil in dry season was particularly very low with increased depth in the profile. The fertility level of most forested soils selected for the present investigation is low according to chemical tests for available nutrient elements.

• Water Engineering Research
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• v.4 no.3
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• pp.111-126
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• 2003

Meteorological data are often needed to evaluate the long-term effects of proposed hydrologic changes. The evaluation is frequently undertaken using deterministic mathematical models that require daily weather data as input including precipitation amount, maximum and minimum temperature, relative humidity, solar radiation and wind speed. Stochastic generation of the required weather data offers alternative to the use of observed weather records. The precipitation is modeled by a Markov Chain-exponential model. The other variables are generated by multivariate model with means and standard deviations of the variables conditioned on the wet or dry status of the day as determined by the precipitation model. Ultimately, the objective of this paper is to compare Richardson's model and the improved weather generation model in their ability to provide daily weather data for the crop model to study potential impacts of climate change on the irrigation needs and crop yield. However this paper does not refer to the improved weather generation model and the crop model. The new weather generation model improved will be introduced in the Journal of KWRA.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 2004.04a
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• pp.149-152
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• 2004

Generally the wafer is increased by 300mm. We are desired that the wafer is prevented from pollutions of metal contaminant on surface of wafer. We have to develop new wafer cleaning process of IC Manufacturing that can reduce DI water and chemical by removal of the wafer cleaning process step. Moreover, it is difficult to control temprature and density of chemical in spite of rapidly increasing automation of system. We design smart module controller for new generation of semiconductor wet station with intelligent algorithm using data that is taken by computer simulation for optimal system.

• Proceedings of the Korean Society Of Semiconductor Equipment Technology
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• 2004.05a
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• pp.123-128
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• 2004

Semiconductor Wet Station has a very important place in semiconductor process. It is important that to discharge chemical with fit concentration and temperature using chemical supply system for clean process. The chemical supply system which is used currently is not only difficult to make a fit mixing rate of chemical which is need in clean process, but also difficult to make fit concentration and temperature. Moreover, it has high stability but it is inefficient spatially because its volume is great. We propose In-line System to improve system with implement analysis of fluid and thermal transfer on chemical supply system and understand problem of system.

• Proceedings of the Korean Society Of Semiconductor Equipment Technology
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• 2003.12a
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• pp.186-191
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• 2003

• Korean Journal of Soil Science and Fertilizer
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• v.23 no.1
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• pp.60-66
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• 1990

Soybean [Glycin max (L.)] cv. Jangbaekkong was inoculated with 5 cultivated- and 5 uncultivated upland soils, in Yeongnam area, as soil inoculum and NifTAL peat inoculum as standard for soil inoculum potentials by Bradyrhizobium japonicum. 120 Bradyrhizobium japonicum isolates out of the soil populations were scored of three colony morphologies, designed "Dry", "Wet", and "Dry/Wet", and symbiotic effectiveness between "Dry" and "Wet" was compared. The results obtained were summarized as follows: 1. Indigenous populations of B. japonicum were above $10^4cells/g$. soil at the cultivated upland soils but were a few at the uncultivated upland soils except a colluvivum, orchard previously, in Yeongnam area. 2. Inoculum potentials of the cultivated upland soils were higher than the NifTAL inoculum and generally, nodule mass compensated nodule number for symbiotic effectiveness of soil populations. 3. Colony morphologies of soil populations showed the different proportions of "Dry" and "Wet" so that "Dry" types were dominant at the cultivated upland soils while "Wet" types at the uncultivated upland soils. 4. "Dry" colony morphology significantly exhibited higher symbiotic effectiveness than "Wet" types in nodule fresh weight, shoot dry weight, and shoot dry weight/nodule fresh weight. Therefore, as long as soil inoculum potentials, the growth of soybean at the cultivated upland soils could presumedly be affected by soil populations of Bradyrhizobium japonicum of "Dry" colony morphology.

• Korean Journal of Soil Science and Fertilizer
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• v.29 no.1
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• pp.60-66
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• 1996

Bradyrhizobium japonicum with different colony morphology populated in five Yeongnam soils of Korea was examined for intrinsic antibiotic resistance to eight antibiotics, serological property by immunoblot and immunodiffusion, and protein profile differentiation by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Colony morphological distribution of one hundred and twenty B. japonicum isolates was 47% for "dry". 41% for "wet", and 12% for "dry/wet" type. The total isolates showed such a strong correlation between the morphology and antibiotic resistance. Colony morphology, which though was dominantly consisted of the same type within a serogroup, wasn't absolutely linked to serological property of B. japonicum. Based on these data, colony morphology was too simple to identify variations with B. japonicum isolates : antibiotic resistance such complicated compared with serological analyses.

• Journal of Korean Society for Atmospheric Environment
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• v.19 no.2
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• pp.217-229
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• 2003

The amounts of nitrogen and sulfur deposited in the region of the Yellow Sea in both dry and wet forms were estimated by using the measurement data published in tile literature during tile past 10 years. In the estimation of dry deposition, concentrations at ground stations including those at a station on the Chinese side and concentrations from shipboard and aircraft measurements were used as well as deposition velocities. Wet deposition flux was determined at ground stations on the Korean side either by taking the flux data themselves or by calculating them from precipitation data in the literature. The dry deposition flux over the Yellow Sea was much greater than those China was confirmed from the fact that the total amount summing wet and dry depositions exceeded the emission amount from Korea. Dry deposition was principally made in the gaseous form due to a larger deposition velocity. Nevertheless, since the deposition velocity over water was smaller than that over the ground, dry deposition of oxidized nitrogen was smaller than wet deposition. As a whole, wet depositions of nitrogen and sulfur were 2.3 and 1.9 times 1arger than corresponding dry depositions, respectively.

• Korean Journal of Soil Science and Fertilizer
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• v.31 no.3
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• pp.259-265
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• 1998

A field experiment was conducted to investigate changes of $NH_4-N$, N uptake, N use efficiency and rice yield by the Latex coated urea(LCU) application on wet-seeding rice from 1994 to 1997. Nitrogen deficiency symptom appeared when LCU was applied as basal dressing continuously until the ripening stage during normal temperature year, but was completed at heading stage during year at high temperature. Percentage recovery of fertilizer N was higher in LCU than in urea but decreased in high temperature. Turn over of N applied as LCU to grain increased more during years high temperature than the normal year. Rice yield with LCU treatment compared to conventional treatment was similar during the normal year but decreased by 6% during year of high temperature. Top dressing of urea at panicle initiation stage in addition to basal dressing of LCU increased rice yield to 12%.

• 한국정보디스플레이학회:학술대회논문집
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• 2009.10a
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• pp.1479-1482
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• 2009

Compared with tilt transfer wet station, vertical etching system has a variety of advantages that are 50% space savings, higher throughput, fairly good etch uniformity over an entire glass for thin film transistor application. The aim of the present work is to study on a vertical etching system to improve the process factors. The computational fluid dynamics analysis is used to demonstrate the change of the etch uniformity as a function of tilt angle of the glass substrate.