• Journal of the Korean association of regional geographers
• /
• v.18 no.4
• /
• pp.473-493
• /
• 2012

Malaria infection is sensitively influenced by regional meteorological conditions along with global climate change. Remote sensing techniques have become an important tool for extraction of climatic and environmental factors, including rainfall, temperature, surface water, soil moisture, and land use, which are directly linked to the habitat qualities of malaria mosquitoes. Improvement of sensor fidelity with higher spatial and spectral resolution, new multinational sensor development, and decreased data cost have nurtured diverse remote sensing applications in malaria research. In 1984, eradication of endemic malaria was declared in Korea, but reemergence of malaria was reported in mid-1990s. Considering constant changes in malaria cases since 2000, the epidemiological management of the disease needs careful monitoring. Geographically, northmost counties neighboring North Korea have been ranked high in the number of malaria cases. High infection rates in these areas drew special attention and led to a hypothesis that malaria dispersion in these border counties might be caused by north-origin, malaria-bearing adult mosquitoes. Habitat conditions of malaria mosquitoes are important parameters for prediction of the vector abundance. However, it should be realized that malaria infection and transmission is a complex mechanism, where non-environmental factors, including human behavior, demographic structure, landscape structure, and spatial relationships between human residence and the vector habitats, are also significant considerations in the framework of medical geography.

• Microbiology and Biotechnology Letters
• /
• v.5 no.4
• /
• pp.177-184
• /
• 1977

Arylsulfatase catalyzes the release of SO$\sub$4//sup2/- from sulfate esters of simple phenols. Arylsolfatase occurs widely in animal tissues and in microorganisms including soil bacteria. Its widespread distribution suggests that it has a rather fundamental function and environmental meaning. It has been shown previously that arylsulfatase of Klebsiella was purified and characterized. A condition of arylsulfatase synthesis was tested with several strains of Serratia. Serratia marcescens could not utilize some sugars, such as xylose, rhamnose, glucosamine and arabinose hut glucose and mannitol as a sole carbon source. However, arylsulfatase synthesis was repressed by glucose but not by mannitol. The enzyme synthesis was repressed ob inorganic sulfate and methionine, and this repression was relieved by addition of tyramine. Arylsulfatase of S. marcescen was purified by fractionation with ammonium sulfate and followed by chromatographies on DEAE-Cellulose CM-Cellulose, and DEAE-Sephadex A-25. The molecular weight of arylsulfatase was determined to be 46,000 by SDS-Gel electrophoresis and 49,000 by Sephadex G-100 column chromatography. The enzyme showed some different properties with that of K. aerogenes. The activity was maximum at pH 6.8. The Km and Vmax values for p-nitrophenyl sulfate were 2.5${\times}$10$\^$－4/ M and 20 nmoles/min/mg protein, respectively. The enzyme showed high activities toward phenyl sulfate, ο-and p-nitro phenyl sulfates, and p-nitrocatechol sulfate. The inhibition of enzyme was strongly affected by hydroxylamine, inorganic fluoride, sulfide and phosphate, but by inorganic sulfate. Like Klebsiella arylsulfatase, tyramine, octopamine, and dopamine gave signifcant inhibitory effect.

• Proceedings of the KSRS Conference
• /
• v.2
• /
• pp.551-554
• /
• 2006

House management is very important in water resource protection in order to provide sustainable drinking water for about four millions population in northern Taiwan. House management can be a simple job that can be done without any ingredient of remote sensing or geographic information systems. Remote sensing and GIS integration for house management can provide more efficient management prescription when land use enforcement, soil and water conservation, sewage management, garbage collection, and reforestation have to be managed simultaneously. The objective of this paper was to integrate remote sensing and GIS to manage houses in a water resource protection district. More than four thousand houses have been surveyed and created as a house data base. Site map of every single house and very detail information consisting of address, ownership, date of creation, building materials, acreages floor by floor, parcel information, and types of house condition. Some houses have their photos in different directions. One house has its own card consists these information and these attributes were created into a house data base. Site maps of all houses were created with the same coordinates system as parcel maps, topographic maps, sewage maps, and city planning maps. Visual Basic.NET, Visual C#.NET have been implemented to develop computer programs for house information inquiry and maps overlay among house maps and other GIS map layers. Remote sensing techniques have been implemented to generate the background information of a single house in the past 15 years. Digital orthophoto maps at a scale of 1:5000 overlay with house site maps are very useful in determination of a house was there or not for a given year. Satellite images if their resolutions good enough are also very useful in this type of daily government operations. The developed house management systems can work with commercial GIS software such as ArcView and ArcPad. Remote sensing provided image information of a single house whether it was there or not in a given year. GIS provided overlay and inquiry functions to automatically extract attributes of a given house by ownership, address, and so on when certain house management prescriptions have to be made by government agency. File format is the key component that makes remote sensing and GIS integration smoothly. The developed house management systems are user friendly and can be modified to meet needs encountered in a single task of a government technician.

• Proceedings of the Korean Geotechical Society Conference
• /
• 2004.03b
• /
• pp.137-145
• /
• 2004

Limestone zone in korea have been distributed to diagonal line so that it is wide from the Gangwondo to the Jeonlanamdo. The limestone cavity and fractured zone were formed by chemical weathering. Limestone cavity and fractured zone was reinforced with cemented milk(w/c=60%)by high pressure jet grouting by tripple -pipe to establish bridge foundation on the ground condition like limestone cavity. To analyze property of limestone and solid of cement milk(w/c=65%), mixed solid of cement, core NX size in the limestone cavity and fractured zone and compressive strength. Seismic tomograpy exploration was pcrforn1cd to analyze deformation modulus of limestone. The analysis suggests that deformation modulus of limestone has effect on uniaxial compressive strength, seismic velocity, seismic elasticity modulus. Average static elasticity modulus of limestone is $5.08{\times}10^5kgf/cm^2$, cement and coal mixed solid is $0.25{\times}10^5kgf/cm^2$, $0.095{\times}10^5kgf/cm^2$. Average seismic velocity of limestone is 5.240m/sec, cement and coal mixed solid is 2,211.3m/sec, 1,447.5m/sec. Average uniaxial compressive strength of limestone was $1,221.3kgf/cm^2$ and limestone specimen mixed with cement milk and solid of cement milk mixed with coal were $125.22kgf/cm^2$, $35kgf/cm^2$ each other. Average friction angle of limestone was $49.14^{\circ}$ and limestone specimen mixed with cement milk and solid of cement milk mixed with coal were $38.39^{\circ}, 25.83^{\circ}$ each other. Average cohesion of limestone was $137.7kgf/cm^2$ and limestone specimen mixed with cement milk and solid of cement milk mixed with coal were $23.5kgf/cm^2$, $15.5kgf/cm^2$ each other. Average deformation modulus of limestone was $2.84{\times}10^5kgf/cm^2$ and limestone specimen mixed with cement milk and solid of cement milk mixed with coal were $0.4{\times}10^5kgf/cm^2, 0.12{\times}10^5kgf/cm^2$ each other. It was analyzed that the elasticity and uniaxial compressive strength, seismic velocity of solid of cement milk mixed limestone pieces and coal had an highly interrelation regardless of existence of limestones pieces and coal but it had shown that limestones had an lower interrelation. In case of field seismic velocity and deformation of limestone, SIC solid of cement milk mixed with coal and limestone pieces had an highly interrelation.

• Korean Journal of Plant Tissue Culture
• /
• v.21 no.2
• /
• pp.85-90
• /
• 1994

Attempts were made to regenerate plants from petiole explane of Forest Pimpinella barchycarpa via repetitive somatic embryogenesis. Effective induction of somatic emb교ogenesis was achieved on both MS and modified $B_{5}\;(mB_{5})$ media containing BA + 2,4-D or BA + 2,4-D + NAA under light condition (16-h photoperiod/day) cultures. The explants exposed to the ligt produced numerous somatic embryos while those kept under the dark did not form any on the same medium. Somatic embryos at different developmental stages were observed to arise within a individual explants. Plantlets could be regenerated on $mB_{5}$ basal medium or $mB_{5}$ containing 0.1 mg/L NAA Secondary adventive embryos were formed on the surface of the somatic embryos. Therefore, repetitive somatic embryogenesis could be achieved by secondary embryogenesis. Although the treatment of 2,4-D or NAA alone was effective in callus formation and growth, but not in induction of somatic embryogenesis. Some explants, cultured on NAA-containing media in darkness, produced only adventive roots. The embryogenic potential was maintained for two years when subcultured to BA and 2,4-D containing media with 5 weeks inteval. Regenerated plantlets were maintained on $mB_{5}$ or MS basal media for 4 to 6 more weeks and transferred to soil of an artificial mixture for acclimation. Most plantlets (more than 97%) survived, and grew without any deformity.

• Korean Journal of Food Science and Technology
• /
• v.45 no.2
• /
• pp.213-220
• /
• 2013

Two types of onions cultivated with different methods of sulfur application (designated as S-1 and S-2) were examined for their physicochemical and sensory properties, and then compared with onions without sulfur application as a control. During cultivation, dietary sulfur methylsulfonylmethane (MSM) was sprayed on the leaves twice starting at 2 months before harvest, with one month intervals for S-1. For S-2, the MSM was applied once onto surface soils before sowing, and then once again on the leaves at 2 months before harvest. Thiosulfinate, a major sulfur-containing compound in onions, increased in the order of control, S-1, and S-2, without noticeable differences in the strength of spicy hot taste and flavor. The S-2 onions demonstrated a total reducing capacity three times higher than control and S-1 did. It indicates that the application of sulfur would positively affect the quality of onions under the condition where sufficient time is given for soil mineralization.

• Korean Journal of Ecology and Environment
• /
• v.34 no.4 s.96
• /
• pp.261-266
• /
• 2001

Effects of elevated carbon dioxide ($CO_2$) on soil microbial processes were studied in a northern peatland. Intact peat cores with surface vegetation were collected from a northern Welsh fen, and incubated either under elevated carbon dioxide (700 ppm) or ambient carbon dioxide (350 ppm) conditions for 4 months. Higher algal biomass was found under the elevated $CO_2$ condition, suggesting $CO_2$ fertilization effect on primary production, At the end of the incubation, trace gas production and consumption were analyzed using chemical inhibitors. For methane ($CH_4$ ), methyl fluoride ($CH_3F$) was applied to determine methane oxidation rates, while acetylene ($C_2H_2$) blocking method were applied to determine nitrification and denitrification rates. First, we have adopted those methods to optimize the reaction conditions for the wetland samples. Secondly, the methods were applied to the samples incubated under two levels of $CO_2$. The results exhibited that elevated carbon dioxide increased both methane production (210 vs. $100\;ng\;CH_4 g^{-1}\;hr^{-1}$) and oxidation (128 vs. $15\;ng\;CH_4 g^{-1}\;hr^{-1}$), resulting in no net increase in methane flux. For nitrous oxide ($N_2O$) , elevated carbon dioxide enhanced nitrous oxide emission probably from activation of nitrification process rather than denitrification rates. All of these changes seemed to be substantially influenced by higher oxygen diffusion from enhanced algal productivity under elevated $CO_2$.

• Tunnel and Underground Space
• /
• v.29 no.6
• /
• pp.468-479
• /
• 2019

It is essential to comprehend coupled hydro-mechanical behavior to utilize subsurface for the recent demand for underground space usage. In this study, we developed a new simulator for numerical simulation as a tool for researching to consider the various domestic field and subsurface conditions. To develop the new module, we combined OpenGeoSys, one of the scientific software package that handles fluid mechanics (H), thermodynamics (T), and rock and soil mechanics (M) in the subsurface with FLAC3D, one of the commercial software for geotechnical engineering problems reinforced. In this simulator development, we design OpenGeoSys as a master and FLAC3D as a slave via a file-based sequential coupling. We have chosen Terzaghi's consolidation problem related to single-phase fluid flow at a saturated condition as a benchmark model to verify the proposed module. The comparative results between the analytical solution and numerical analysis showed a good agreement.

• Korean Journal of Weed Science
• /
• v.15 no.3
• /
• pp.175-182
• /
• 1995

The experiment was conducted to obtain basic information on weed ecology and effective weed control in direct-seeded rice Gelds at National Yeongnam Agricultural Experiment Station in 1994. Double cropping system of rice-barley reduced weed occurrence about 30% as compared with rice single cropping due to allelopathic effect of barley residue or stubble. Occurrences of red rice (weedy rice), barnyard grass and water foxtail were closely related with tillage method; the greatest occurred in no tillage plot followed by rotavation only and plow plus rotavation. Period of seed germination of barnyard grass and carbgrass varied with temperature and soil depth. In the same environmental condition, the germination period of barnyard grass shortened 3 to 5 days as compared with that of carbgrass. Two systematic applications of herbicides, that is, the first application at 10 to 15 days after seeding and the second at just after flooding, were the most recommendable system in dry-seeded rice field in terms of weed suppression and yield capacity.

• Korean Journal of Plant Resources
• /
• v.29 no.1
• /
• pp.39-45
• /
• 2016

Pink Rot on melon and White Stain Symptom on grape are caused by Trichothecium roseum, one of the most important diseases of grape and melon. These diseases have been occurred in national-wide in Korea and causes irreversible damage on the grape and the melon at harvest season. This research presents the evaluation of the capacity of Bacillus subtillis HK2 to protect both melon and grape against T. reseum and establishes its role as a biocontrol agent. In this study, we isolated a Bacillus strain HK2 from rhizosphere soil, identified it as Bacillus subtillis by 16S rRNA analysis and demonstrated its antifungal activity against T. roseum. Under I-plate assay it was observed that the effect of hyphal growth inhibition was not due to production of volatile compounds. The optimum culture condition of HK2 was found at 30℃ and initial pH of 7.0. Application of HK2 culture suspension reduced 90.2% of white stain symptom on grape as compared to control, resulting in greater protection to grape against T. roseum infestation. Butanol extract of HK2 culture purified using flash column chromatography. The antifungal material was a polar substance as it showed antifungal activity in polar elute. Therefore, our results indicated a clear potential of B. subtilis HK2 to be used for biocontrol of Pink rot in melon and white stain symptom on grape caused by T. roseum.