• Korean Journal of Agricultural and Forest Meteorology
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• v.6 no.4
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• pp.272-289
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• 2004

The spatial resolution of local weather and climate information for agronomic practices exceeds the current weather service scale. To supplement the insufficient spatial resolution of official forecasts and observations, gridded climate data are frequently generated. Most ecological models can be run using gridded climate data to produce ecosystem responses at landscape scales. In this lecture, state of the art techniques derived from geospatial climatology, which can generate gridded climate data by spatially interpolating point observations at synoptic weather stations, will be introduced. Removal of the urban effects embedded in the interpolated surfaces of daily minimum temperature, incorporation of local geographic potential for cold air accumulation into the minimum temperature interpolation scheme, and solar irradiance correction for daytime hourly temperature estimation are presented. Some experiences obtained from their application to real landscapes will be described.

• Journal of Astronomy and Space Sciences
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• v.39 no.2
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• pp.23-33
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• 2022

Electron density irregularities in the equatorial ionosphere at night are understood in terms of plasma bubbles, which are produced by the transport of low-density plasma from the bottomside of the F region to the topside. Equatorial plasma bubbles (EPBs) have been detected by various techniques on the ground and from space. One of the distinguishing characteristics of EPBs identified from long-term observations is the systematic seasonal and longitudinal variation of the EPB activity. Several hypotheses have been developed to explain the systematic EPB behavior, and now we have good knowledge about the key factors that determine the behavior. However, gaps in our understanding of the EPB climatology still remain primarily because we do not yet have the capability to observe seed perturbations and their growth simultaneously and globally. This paper reviews the occurrence climatology of EPBs identified from observations and the current understanding of its driving mechanisms.

• Proceedings of the KGS Conference
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• 2002.11a
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• pp.9-18
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• 2002

I. Trend of the Association of Japanese Geographers in 1970-1980. II. Reformation of the Association of Japanese Geographers Since 1980. III. Changing Era Revolution of Universities. IV. Geographical Education in the Association of Japanese Geographers. V. Overseas field WOrs in the Association of Japanese Geographers. VI. Recently Trend of Korean Study in the Field of Climatology and Environmental Geography in the Association of Japanese Geographers.

• Proceedings of The Korean Society of Agricultural and Forest Meteorology Conference
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• 2014.10a
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• pp.191-194
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• 2014

• Proceedings of The Korean Society of Agricultural and Forest Meteorology Conference
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• 2014.10a
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• pp.195-198
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• 2014

• Proceedings of The Korean Society of Agricultural and Forest Meteorology Conference
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• 2014.10a
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• pp.199-204
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• 2014

• Asian-Australasian Journal of Animal Sciences
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• v.10 no.5
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• pp.514-518
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• 1997

This study was designed to record the ovarian response towards a combined administration of heterologous buffalo FSH (buFSH) and LH (buLH) in goats. The impact of such a treatment on ovarian structures and on the plasma profile of the ovarian sex steroids (estradiol $17-{\beta}$ and progesterone) was studied. The buFSH and buLH were isolated from the buffalo pituitaries involving a procedure of ethanolic extraction, acetone precipitation followed by metaphosphoric acid - ammonium sulphate fractionation. Both gonadotrophin samples prepared were found biologically active and potent. There was an increase in the total number of follicles in the treated group ($12.66{\pm}1.24$) vis-a-vis the control group ($8.50{\pm}2.06$). However, the percentage ($51.48{\pm}6.37$) of large follicles were found reduced ($23.74{\pm}5.93$) following the treatment. Again the number of corpora lutea were observed significantly higher ($2.33{\pm}0.47C.L.$) in the treated group than (1 C. L.) in the control group. The peak plasma estradiol- $17{\beta}$ levels achieved, were much higher ($17.16{\pm}9.52pg/ml$) in the treated group, than the peak ($7.22{\pm}1.67pg/ml$) achieved in the control group. Similar trend was observed with respect to the progesterone levels (higher in the treated group). This study thus indicated that, a combined administration of heterologous buffalo FSH and LH to goats speeded up development of larger follicles nearing the ovulation stage. This population of the follicles subsequently got reduced and lead to the formation of the increased number of the corpora lutea observed in this study.

• Korean Journal of Agricultural and Forest Meteorology
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• v.12 no.1
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• pp.63-73
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• 2010

A comprehensive mapping project for agroclimatic zoning in South Korea will end by April 2010, which has required 4 years, a billion won (ca. 0.9 million US dollars) and 22 experts from 7 institutions to complete it. The map database from this project may be categorized into primary, secondary and analytical products. The primary products are called "high definition" digital climate maps (HD-DCMs) and available through the state of the art techniques in geospatial climatology. For example, daily minimum temperature surfaces were prepared by combining the climatic normals (1971-2000 and 1981-2008) of synoptic observations with the simulated thermodynamic nature of cold air by using the raster GIS and microwave temperature profiling which can quantify effects of cold air drainage on local temperature. The spatial resolution of the gridded climate data is 30m for temperature and solar irradiance, and 270m for precipitation. The secondary products are climatic indices produced by statistical analysis of the primary products and includes extremes, sums, and probabilities of climatic events relevant to farming activities at a given grid cell. The analytical products were prepared by driving agronomic models with the HD-DCMs and dates of full bloom, the risk of freezing damage, and the fruit quality are among the examples. Because the spatial resolution of local climate information for agronomic practices exceeds the current weather service scale, HD-DCMs and the value-added products are expected to supplement the insufficient spatial resolution of official climatology. In this lecture, state of the art techniques embedded in the products, how to combine the techniques with the existing geospatial information, and agroclimatic zoning for major crops and fruits in South Korea will be provided.

• Proceedings of the Korea Water Resources Association Conference
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• 2023.05a
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• pp.314-314
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• 2023

Extreme climate events can have a large impact on human life by hampering social, environmental, and economic development. Global circulation models (GCMs) are the widely used numerical models to understand the anticipated future climate change. However, different GCMs can project different future climates due to structural differences, varying initial boundary conditions and assumptions about the physical phenomena. The multi-model ensemble (MME) approach can improve the uncertainties associated with the different GCM outcomes. In this study, a comprehensive rating metric was used to select the best-performing GCMs out of 11 CMIP5 and 13 CMIP6 GCMs, according to their skills in terms of four temporal and five spatial performance indices, in replicating the 21 extreme climate indices during the baseline (1975-2017) in South Korea. The MME data were derived by averaging the simulations from all selected GCMs and three top-ranked GCMs. The random forest (RF) algorithm was also used to derive the MME data from the three top-ranked GCMs. The RF-derived MME data of the three top-ranked GCMs showed the highest performance in simulating the baseline extreme climate which was subsequently used to project the future extreme climate indices under both the representative concentration pathway (RCP) and the socioeconomic concentration pathway scenarios (SSP). The extreme cold and warming indices had declining and increasing trends, respectively, and most extreme precipitation indices had increasing trends over the period 2031-2100. Compared to all scenarios, RCP8.5 showed drastic changes in future extreme climate indices. The coasts in the east, south and west had stronger warming than the rest of the country, while mountain areas in the north experienced more extreme cold. While extreme cold climatology gradually declined from north to south, extreme warming climatology continuously grew from coastal to inland and northern mountainous regions. The results showed that the socially, environmentally and agriculturally important regions of South Korea were at increased risk of facing the detrimental impacts of extreme climatology.

• Asian-Australasian Journal of Animal Sciences
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• v.23 no.7
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• pp.880-888
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• 2010

The ameliorative effect of salts and ascorbic acid polyphosphate supplementation on heat stress was studied in buffaloes. Adult buffaloes of either sex were randomly divided into 2 groups of 4 animals each. Group I served as control and Group II was supplemented with sodium bicarbonate, potassium carbonate and ascorbic acid polyphosphate. All the animals were exposed to two conditions of temperature and humidity: hot-dry and hot-humid in a psychrometric chamber for 4 h daily for 10 days. Blood was collected on day 1, 5 and 10 of treatment. The activities of catalase and superoxide dismutase (SOD), concentrations of serum glutathione (GSH), cortisol, sodium, potassium, and chloride and lipid peroxidation were estimated in serum. Lymphocyte proliferation was assessed in blood. The activities of catalase and SOD, serum concentration of GSH, sodium, potassium and chloride decreased while lipid peroxidation and serum cortisol increased in both groups when subjected to heat stress. Dietary supplementation resulted in further decreasing of the enzyme activities but increasing of the serum concentrations of GSH, sodium, potassium and chloride. Lipid peroxidation and serum cortisol increased in the supplemented group in both types of stress. Dietary supplementation caused an increase in lymphoproliferative response to con A. Thus, supplementation of ascorbate in addition to electrolytes relieves the animals of oxidative stress and boosts cell mediated immunity.