• Korean Journal of Agricultural and Forest Meteorology
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• v.18 no.1
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• pp.42-54
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• 2016

It is highly anticipated that warming temperature resulting from global climate change will affect the phenological pattern of kiwifruit, which has been commercially grown in Korea since the early 1980s. Here, we present the potential impacts of climate change on the variations of flowering day of a gold kiwifruit cultivar, Haegeum, in the Jeonnam Province, Korea. By running six global climate models (GCM), the results from this study emphasize the uncertainty in climate change scenarios. To predict the flowering day of kiwifruit, we obtained three parameters of the 'Chill-day' model for the simulation of Haegeum: $6.3^{\circ}C$ for the base temperature (Tb), 102.5 for chill requirement (Rc), and 575 for heat requirement (Rh). Two separate validations of the resulting 'Chill-day' model were conducted. First, direct comparisons were made between the observed flowering days collected from 25 kiwifruit orchards for two years (2014-15) and the simulated flowering days from the 'Chill-day' model using weather data from four weather stations near the 25 orchards. The estimation error between the observed and simulated flowering days was 5.2 days. Second, the model was simulated using temperature data extracted, for the 25 orchards, from a high-resolution digital temperature map, resulting in the error of 3.4 days. Using the RCP 4.5 and 8.5 climate change scenarios from six GCMs for the period of 2021-40, the future flowering days were simulated with the 'Chill-day' model. The predicted flowering days of Haegeum in Jeonnam were advanced more than 10 days compared to the present ones from multi-model ensemble, while some individual models resulted in quite different magnitudes of impacts, indicating the multi-model ensemble accounts for uncertainty better than individual climate models. In addition, the current flowering period of Haegeum in Jeonnam Province was predicted to expand northward, reaching over Jeonbuk and Chungnam Provinces. This preliminary result will provide a basis for the local impact assessment of climate change as more phenology models are developed for other fruit trees.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.29 no.3
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• pp.332-344
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• 1996

The vertical profiles of the natural $^{210}Po,\;^{210}Pb\;and\;^{234}Th$, activities were measured at the upper 150 m or 200 m of water column from west-east intersection in the east-southern coastal area of the Korea Peninsula during the period from 26 to 29 April 1994 to compare the removal rates (residence time) and removal processes for $^{210}Po\;and\;^{234}Th$. At the inshore stations, the $^{210}Po$ activity was generally higher in the thermocline and its under layer than in the surface mixed layer, while represented the reversed pattern at the offshore stations. However, the $^{210}Pb$ activity decreased generally with depth. Also, the activity of $^{210}Po$ relative to its parent $^{210}Pb$ was deficient in the water column above the main thermocline, but was slightly excess or close to equilibrium in the thermocline and its under layer. The vertical profiles for the activity of $^{210}Pb$ relative to its parent $^{226}Ra$ showed the reversed pattern with the vertical variation of $^{210}Po$ excess (or deficiency). The $^{234}Th$ activity was significantly lower in the surface mixed layer and thermocline than in the deeper layer. The residence time of $^{210}Po$ ranged from 1 to 4 years at the five stations except station E8 that showed yet long residence time (approximately 10 years). The long residence time at the station E8 may resulted from the thicker surface mixed layer and subsequent the vertical mixing of $^{210}Po$ which was recycled in the lower surface mixed layer compared to at the other stations. Also, the residence time of $^{210}Po$ was shorter at the inshore stations than at the offshore stations. However, the residence time of $^{234}Th$ ranged from 52 to 74 days at all station without the significant variation, was very much shorter relative to the residence time of $^{210}Po$. The correlation between the removal rate of dissolved $^{234}Th$ and the concentration of total suspended matter (TSM) was generally positive. Therefore, it seems that the major route of the removal mechanism of $^{234}Th$ from seawater in the surface mixed layer is via adsorption onto suspended particle surfaces (most likely inorganic particles) and subsequent settling to the bottom layer. Between the removal rate of dissolved $^{210}Po$ and the concentration of chlorophyll-a was positively good correlation. Consequently, most likely the removal of $^{210}Po$ may be occurred by uptake to organisms (mainly such as planktonic debris or fecal pellets) and subsequent settling.

• Korean Journal of Environment and Ecology
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• v.29 no.6
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• pp.850-857
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• 2015

This study was aimed to identify the characteristics of nest and breeding site conditions of Chinese Egret (Egretta europhotes) that breed in the uninhabited islets of the western coast of South Korea. It is expected that the information collected through this study can contribute to providing basic information required when building and managing artificial nests in their natural breeding habitats. Chinese Egrets make their nests in the shrub layers of Long Leaf Elaeagnus (Elaeagnus macrophylla), Arrow Bamboo (Pseudosasa japonica), and Baby Brier (Rosa multiflora). A total of 50 breeding nests of Chinese Egret were investigated in June and July 2013, with area-wise distribution as follows: Seomando (11 nests), Hwangseodo (14 nests), Mokdo (10 nests), and Napdaekiseom (15 nests). Vegetation coverage (cover, %), height from the ground to the top (height, cm), thickness from top to bottom of the nest (thickness, cm), reuse period, major axis (cm), minor axis (cm), and depth (cm) of each nest were measured. According to the results of the study on the nest characteristics of 4 breeding groups, the nests in Hwangseodo had the highest coverage, the nests in Mokdo were built in the highest places, the nests in Napdaekiseom showed the longest reuse period, and the nests in Mokdo had the greatest depth. The differences in height and reuse period were significant between Mokdo and Napdaekiseom. Moreover, there were significant differences in reuse period and depth between Seomando and Hwangseodo. There were significant differences in cover, minor axis, and depth between breeding groups that built nests on Arrow Bamboo (Mokdo and Napdaekiseom) and Baby Brier (Seomando and Hwangseodo). Nest characteristics of Chinese Egret were generally similar, while some variables showed different values for different breeding groups.

• Korean Journal of Agricultural Science
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• v.7 no.1
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• pp.52-58
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• 1980

This study was conducted to detect copper which is considered in the soils of orchards, since copper fungicide has been applied to fruit trees. Soil samples taken from the fields of the chief producing districts of apple (Chungju, Yesan, Daegu), pear (Yangju, Bucheon, Seonghwan) and citrus (Seogypo in Jeju island) were analysed by an atomic absorption spectrophotometer. The results obtained were summarized as follows ; 1. In orchards of apple, the amount of copper of soils from Yesan, Chungju and Daegu were ranged 2.6-171.3ppm, 2.2-136.1ppm and 14.3-134.6ppm, respectively. Very little copper was detected from the soils in the field which has been cultivated for less than 20 years. About 100ppm and 130-170ppm of copper were detected in the field which has been cultivated for 30 years and for 50-60 years, respectively. Most of the copper was detected in the surface layer of soils (0-10cm), while very low content of copper was detected in the deeper layer of soils (10-20cm). 2. In orchards of pear, 20-30ppm of copper was detected from the surface of soils in the field which has been cultivated for more than 30 years and the highest level of copper, 36.8ppm, was detected from Yangju area. The amount of copper of soils from Yangju, Seonghwan and Bucheon were ranged 3.6-36.8ppm, 9.7-19.4ppm and 3.6-24.7ppm, respectively. 3. In orchards of citrus of Jeju island, only trace amount and 23-38ppm of copper were detected in the fields cultivated for 15 years and 20-30 years, respectively. The highest level of copper, 57ppm, was detected from the surface layer of soils in the field which has been cultivated for 35 years, but in most of the soil samples tested, only the natural background level of copper, about 20ppm, was detected. 4. The levels of copper residue in all the soil samples tested were lower than the tolerance level (125ppm of copper which is extracted in 0.1N-HCl solution), except those of copperr residue, 130-170ppm, that were detected from the orchards of apple which have been under cultivation for 50-60 years. Hence no problem for the farming could be speculated with the present concentration of copper analysed.

• Journal of Preventive Medicine and Public Health
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• v.9 no.1
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• pp.55-64
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• 1976

This paper presents the results of a survey for the causes of sensori-neural hearing impairment in Korea, The subjects were 1,676 children of total 2,928 enrolled in 16 Deaf Schools; two schools in each area of Seoul, Busan, Kyoungbook, Kyoungnam, Kyounggi and Chunbug, and each one in Chungnam, Chungbug, Chunnam and Jaeju. The data were collected by questionaire with 28 items distributed to their parents. The filling in the check lists were performed by their class teachers, interviewer, for 18 months from September, 1975 to february, 1976. The questionable or missed problems were reaffirmed. The results obtained were as follows. Most of the reasons, 78.5% were acquired characters that could be developed during pregnant period, the time of delivery and the time of after birth. The pure hereditary reasons except the cases complexed with one or two were only 11.3%. Those who could not be defined with any reasons were 10.2%. Among the acquired causes, 5.8% of total subjects were developed for pregnancy: 3.3%, during delivery; and 69.7%, after birth. In the pregnant period, the drug intoxications were 2.4% of total subjects, several diseases such as influenja, bleeding, surgical operation, venereal diseases and rubella etc. were about one percent, and the accompanied with some symptoms of pregnancy intoxication and traumatic events were 2.4%, During time, the cases with delayed rhythmical pain were 16 persons, the immaturities were 11, the asphyxial cases were nine, the errors of forceps delivery were seven, the cases of low body weight inspite of full term were four, the cases with cesarian section were three, the head injuries were two, and the accompanied with three kinds of above reasons were three. During after birth, the cases with acute communicable diseases were 35.4% of total subjects, the fever unknown origin were 16.1%, the chronic otitis media were 3.7%, the meningitis were 3.5%, the gastric and nutritional diseases were 3.5%, the drug intoxications were 4.8%, the blood diseases were 0.3% and the other causes were 2.2%. Here by acute communicable diseases, some importants were measle, 10.1% of total subjects; meningitis, 7.3%; convulsion with some reasons, 4.9%; poliomyelitis. 3.2%; encephalitis, 2.4%; and mumps, rubella, pertusis, scarlet fever, and small pox were somewhat played a role in. Among 59 cases with train diseases, 53 were concussion by the accidents, such as traffic and falling or sliping down etc., the cerebral paralysis and hydrocephalus were two, respectively. And the blood diseases were severe newjaundice in all five cases. If we were summarized with the above mentioned, most of the hearing impairments were introduced by the combined reasons with familial or hereditary factors and the acquired, than by a simple disease. Among the congenital or hereditary hearing impairments classified to now a day, we suppose that the many cases with the acquired causes during pregnancy, delivery and after birth were complexed. Subsequently, the maternal and child health should be more and more developed in our country, also.

• Journal of radiological science and technology
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• v.35 no.2
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• pp.119-124
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• 2012

Recently, Glass Dosimeter (GD) with thermoluminescent Dosimeter (TLD) are comprehensively used to measure absorbed dose from diagnostic field to therapy field that means from low energy field to high energy field. However, such studies about dose characteristics of GD, such as reproducibility and energy dependency, are mostly results in high energy field. Because characteristic study for measurement devices of radiation dose and radiation detector is performed using 137Cs and 60Co which emit high energy radiations. Thus, this study was evaluated the linearity according to Piranha dose which measured by changing tube voltage (50kV, 80kV and 100kV which are low energy radiations), reproducibility and reproducibility according to delay time using GD. Measurement of radiation dose is performed using internal detector of Piranha 657 which is multi-function QA device (RTI Electronic, Sweden). Condition of measurement was 25mA, 0.02sec, 2.5mAs, SSD of 100 cm and exposure area with $10{\times}10cm^2$. As above method, GD was exposed to radiation. Sixty GDs were divided into three groups (50kV, 80kV, 100kV), then measured. In this study, GD was indicated the linearity in low energy field as high energy existing reported results. The reproducibility and reproducibility according to delay time were acceptable. In this study, we could know that GD can be used to not only measure the high energy field but also low energy field.

• Weed & Turfgrass Science
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• v.5 no.4
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• pp.203-212
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• 2016

In order to investigate actual pesticide usage, this survey was carried out with farmers growing four crop groups, leaf vegetables, fruit vegetables, fruits, and rice from 2012 to 2015. Five hundred sixty farmers were selected in main crop production areas and were asked about their pesticide uses during the growing season. Investigations on pesticide damages to crop in recent 5 years showed that fruit vegetables had the highest proportion of damage at 14%, followed by rice at 11%, orchards at 11%, and leaf vegetables at 8%. Compared to the results of a pilot study which took place from 2009 to 2011, fruit vegetable damage increased by 4% while damage to rice and orchards decreased by 7-9%. This means continuous education on mixed spraying, usage methods, and precaution is required. In the survey on the safety guidelines for pesticide use, 6 items were well observed (89.0-95.0%), but one item for use of protective gear had the lowest observance (81.7%). A measure for protective gear for poisoning prevention is required. The survey of pesticide usage per area ($kg\;a.i.\;ha^{-1}$) showed that 1.65, 4.93, 10.98, and $3.16kg\;a.i.\;ha^{-1}$ of pesticides were applied to leaf vegetables (6 species), fruit vegetables (6 species), fruits (6 species), and rice, respectively, which decreased from the usage reported in the pilot study. This change was likely caused by more effective pesticides and fewer pest outbreaks; therefore, shipments of pesticides have been decreasing. In the case of paddy rice herbicides, 43 products, including butachlor, were used for $1.3kg\;ha^{-1}$. Herbicides represent 44% of pesticides used in paddy rice.

• Food Science and Preservation
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• v.15 no.5
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• pp.711-718
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• 2008

Dombaeki, a traditional salted shark meat, has been widely used as a customary religious food in the Daegu-Gyeongbuk area of Korea. Two different sharks, Sphyrna zygaena (SZ) and Isurus oxyrinchus (IO) are traditionally used to prepare Dombaeki. Chemical components, lipid classes, fatty acid levels, and sterol compositions of meats prepared from the two sharks were investigated. There were no significant differences in chemical composition between the two dried shark meats. Major amino acids in shark meat were leucine, lysine, arginine, proline, isoleucine, valine, phenylalanine, glutamic acid, and asparagine, which together accounted for about 40% of total amino acids. Levels of amino acids in IO meat were higher than in SZ meat. Major fatty acids in the two shark meats were palmitic ($C_{16:0}$), stearic ($C_{18:0}$), oleic ($C_{18:1}$), arachidonic ($C_{20:4}$), and docosahexanoic (DHA, $C_{22:6}$) acids, which accounted for about 80% of total fatty acids. Notably, IO meat showed higher amounts of DHA (31.8%) and eicosapentanoic acid (EPA, 1.8%) than did SZ meat. The two shark meats showed similar dry weight levels of total lipids, with triacylglycerols, free fatty acids, sterols, and phospholipidscomprising on average 5.0, 2.0, 13.0 and 63.0% of total lipids, respectively. The dominant classes of phospholipids were mainly phosphatidylcholine (PC) and phosphatidylethanolamine (PE). PC content in the two shark meats was higher than that of PE, although the differencewas not great. The major fatty acids in phospholipids were myristic, palmitoleic, stearic, and docosanoic acids. Total volatile basic nitrogen content and the pH of SZ meat were lower than those of IO meat, whereas the Hunter's 'a' and 'b' values of SZ meat were higher than those of IO meat. These results suggest that shark meat may be useful as a functional food to prevent several degenerative diseases.

• Korean Journal of Soil Science and Fertilizer
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• v.32 no.4
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• pp.383-397
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• 1999

For sites to be investigated, the results of such an investigation can be used in determining foals for cleanup, quantifying risks, determining acceptable and unacceptable risk, and developing cleanup plans t hat do not cause unnecessary delays in the redevelopment and reuse of the property. To do this, it is essential that an appropriately detailed study of the site be performed to identify the cause, nature, and extent of contamination and the possible threats to the environment or to any people living or working nearby through the analysis of samples of soil and soil gas, groundwater, surface water, and sediment. The migration pathways of contaminants also are examined during this phase. Key aspects of cost-effective site assessment to help standardize and accelerate the evaluation of contaminated soils at sites are to provide a simple step-by-step methodology for environmental science/engineering professionals to calculate risk-based, site-specific soil levels for contaminants in soil. Its use may significantly reduce the time it takes to complete soil investigations and cleanup actions at some sites, as well as improve the consistency of these actions across the nation. To achieve the effective site assessment, it requires the criteria for choosing the type of standard and setting the magnitude of the standard come from different sources, depending on many factors including the nature of the contamination. A general scheme for site-specific assessment consists of sequential Phase I, II, and III, which is defined by workplan and soil screening levels. Phase I are conducted to identify and confirm a site's recognized environmental conditions resulting from past actions. If a Phase 1 identifies potential hazardous substances, a Phase II is usually conducted to confirm the absence, or presence and extent, of contamination. Phase II involve the collection and analysis of samples. And Phase III is to remediate the contaminated soils determined by Phase I and Phase II. However, important factors in determining whether a assessment standard is site-specific and suitable are (1) the spatial extent of the sampling and the size of the sample area; (2) the number of samples taken: (3) the strategy of taking samples: and (4) the way the data are analyzed. Although selected methods are recommended, application of quantitative methods is directed by users having prior training or experience for the dynamic site investigation process.

• Korean Journal of Soil Science and Fertilizer
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• v.38 no.2
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• pp.59-65
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• 2005

This study was performed to estimate the soil loss on a national scale and grade regions with the potential risk of soil erosion. Universal soil loss equation (USLE) for rainfall and runoff erosivity factors (R), cover management factors (C) and support practice factors (P) and revised USLE for soil erodibility factors (K) and topographic factors (LS) were used. To estimate the soil loss, the whole nation was divided into 21,337 groups according to city county, soil phase and land use type. The R factors were high in the southern coast of Gyeongnam and Jeonnam and part of the western coast of Gyeonggi and low in the inland and eastern coast of Gyeongbuk. The K factors were higher in the regions located on the lower streams of rivers and the plain lands of the western coast of Chungnam and Jeonbuk. The average slope of upland areas in Pyeongchang-gun was the steepest of 30.1%. The foot-slope areas from the Taebaek Mountains to the Sobaek Mountains had steep uplands. Total soil loss of Korea was estimated as $50{\times}10^6Mg$ in 2004. The potential risk of soil erosion in upland was the severest in Gyeongnam and the amount of soil erosion was the greatest in Jeonnam. The regions in which annual soil loss was estimated over $50Mg\;ha^{-1}$ were graded as "the very severe" and their acreage was $168{\times}10^3ha$ in 2004. The soil erosion maps of city/county of Korea were made based on digital soil maps with 1:25,000 scale.