• Current Research on Agriculture and Life Sciences
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• v.11
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• pp.71-79
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• 1993

This study was conducted to obtain the basic information for the classification of Perilla spp. based on their major morphological characteristics for the 20 local collections of perilla distributed in Korea. The results of this experiment were summarized as follows : Several morphological characteristics were investigated. Seed color was classified to four groups with greshywhite, greshybrown, brown and darkbrown. The 1,000 grain weight, 11 accessions were below 3.5g, four accessions was 3.6g to 4.5g and five accessions was 4.5g to 5.07g. There was two types of stem color, red and green, 15 accessions was green and 5 accessions including Andongjaerae, Yeupsil, Ockdong, Cheongsongjaerae and Chugjaso were red color. In fatty acid composition was 60% in average. Among 20 accessions, Euseongjaerae showed the highest content(65%) and Yeongyangjaerae the lowest(54%) linolenic acid content. In the cytogenetical studies on the four accessions including Andong, Yeupsil, Yeongkwang and Daeyeong, the number of chromosomes were 2n=38.

• Journal of Korean Society of Forest Science
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• v.80 no.4
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• pp.360-368
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• 1991

Utilizing chi-square test statistics, inter-species association and covariation were analyzed for the 37 woody plant species in a deciduous forest dominated by Quercus mongolica and Q. variabilis. within 50 temporarily established $20m{\times}20m$ square quadrats, the association for each pair of species was presented based on the presence-absence parameters. Acer palmatum had significant positive association with Acer mono and Kalopanax pictus, but negative association with Pinus densiflora. Other positively associated species pairs were Prunus sargentii-Macckia amurensis, Quercus serrata-Kalopanax pictus, Symplocos chinensis var. pilosa-Euonymus oxyphyllus, and Ulmus davidiana var. japonica-Lindera obtusiloba. The covariation far each pair of species was evaluated based on the quantitative measures, density and basal area. Overall results showed that the association and covariation values among species generally agreed with each other. Because covariation was calculated by density and basal area of the tallied species in the sample plots, the number of species pairs of covariation tended to be greater than those of association. Especially, Pinus densiflora, considered to be pioneer species in the successional stage, had negative covariation with most of climax species. These ecological information could be applied to silvicultural practices, such as ecosystem classification, establishment of mixed hardwood forest, and tending operations for marking crop trees and desirable species.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.24 no.3
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• pp.293-299
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• 2014

Objectives: The main objective of this study is to investigate domestic usage amount of insecticide for vegetable cultivation to provide fundamental data for establishing job-exposure matrix(JEM) related to farmers treating agricultural insecticide. Materials and Methods: The survey on domestic usage amount of insecticide for vegetable cultivation was conducted by two research methods. The first method is to utilize agricultural pesticides published annually from Korea Crop Protection Association(KCPA). The second method is to apply cultivation area of vegetable announced officially from Statistics Korea(SK). An estimation of domestic usage amount of insecticide for vegetable cultivation through the second method was done by multiplying total cultivation area of vegetable($m^2$) with optimal spray amount of insecticide for vegetable cultivation per unit cultivation area of vegetable ($kg/m^2$). Results: As a result of analysis of public data related to insecticide for vegetable cultivation, it was found that its domestic usage amount has decreased gradually from the first sale year(1969) to current year(2012). There is, however, a considerable difference of annual usage trend of insecticide for vegetable cultivation between shipments and estimation. The annual usage trends of insecticide for vegetable cultivation based on regional classification were different from those based on total aspect. Conclusions: The region which used insecticide for vegetable cultivation the most in Korea was Jeolla-do, followed by Gyeonsang-do, Chungcheong-do, Seoul/Gyeonggi-do, Gangwon-do and Jeju-do. Substantially, mean ratio of usage amounts of insecticide based on shipments and those based on estimation by cultivation area was $281{\pm}115%$, which indicates that usage amounts of insecticide estimated by cultivation area are three times lower than those based on shipments.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.24 no.1
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• pp.59-64
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• 2014

Objectives: The principal aim of this study is to investigate and analyze domestic usage amounts of insecticide in rice cultivation in order to provide fundamental data for establishing a job-exposure matrix(JEM) related to farmers working with agricultural insecticides. Materials and Methods: An investigation of domestic usage amounts of insecticides rice cultivation was performed through two methods. The first method utilized information on agricultural pesticides published annually by the Korea Crop Protection Association(KCPA). The second method made use of area of cultivation of rice as officially determined by Statistics Korea(SK). An estimation of domestic usage of insecticides in rice cultivation through the second method was determined by multiplying the total cultivation area of rice($m^2$) by the optimal spray volume of insecticides for rice cultivation per unit of cultivation area($kg/m^2$). Results: As a result of the analysis of public data regarding insecticides in rice cultivation, it was found that the domestic usage amount has decreased sharply from the first year of market sales(1969) to the final data year(2012). There is little difference in the annual usage trend of insecticides in rice cultivation between shipment and estimation. Also, the annual usage trends of insecticides in rice cultivation based on regional classification were nearly similar to those based on the overall aspect. Conclusions: The region which used the largest volume of insecticide in rice cultivation in Korea was the Jeolla Provinces, followed by the Gyeonsang Provinces, the Chungcheong Provinces, Seoul/Gyeonggi Province, Gangwon Province and Jeju Province. Substantially, the mean ratio of usage amounts of insecticide based on shipments and those based on estimation by cultivation area was $96{\pm}29%$, which indicates that the domestic usage amount of insecticide for rice cultivation corresponded to the optimal spray standard per unit area.

• Journal of Korean Society of Forest Science
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• v.86 no.1
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• pp.46-55
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• 1997

This study tried to categorize the types of mountain-village areas in terms of some key variables representing the socio-economic and natural characteristics in order to provide basic information for policy formation of mountain areas. Cross-sectional data of the year 1990 for 900 sub-counties were collected to analyse the characteristics of mountain-village areas. Eleven variables were selected to classify the types of sub-county levels. According to the results of the study, the socio-economic conditions of mountain-village areas represented by the number of corporations, number of non-farming households, and population density of mountain-village areas were found to be inferior to other parts of the nation while the proportion of forest land, share of non-paddy crop fields, distance from cities, percentage of farming households, and elevation from the sea-level were higher to the other areas. By the principal factor analysis, the key variables representing industrial development, mountain-ousness, and accessibility from near cities were selected. By a cluster analysis employing the selected variables, 5 different types of mountain-village areas were categorized.

• Journal of the Korean Association of Geographic Information Studies
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• v.15 no.3
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• pp.66-80
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• 2012

It is necessary to normalize spectral image values derived from multi-temporal satellite data to a common scale in order to apply remote sensing methods for change detection, disaster mapping, crop monitoring and etc. There are two main approaches: absolute radiometric normalization and relative radiometric normalization. This study focuses on the multi-temporal satellite image processing by the use of relative radiometric normalization. Three scenes of KOMPSAT-2 imagery were processed using the Multivariate Alteration Detection(MAD) method, which has a particular advantage of selecting PIFs(Pseudo Invariant Features) automatically by canonical correlation analysis. The scenes were then applied to detect disaster areas over Sendai, Japan, which was hit by a tsunami on 11 March 2011. The case study showed that the automatic extraction of changed areas after the tsunami using relatively normalized satellite data via the MAD method was done within a high accuracy level. In addition, the relative normalization of multi-temporal satellite imagery produced better results to rapidly map disaster-affected areas with an increased confidence level.

• Asian Journal of Turfgrass Science
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• v.23 no.2
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• pp.253-264
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• 2009

The purpose of seed certification is to preserve the genetic purity and identity of seed varieties. This study is to provide information concerning seed certification procedures and certification standards of Kentucky bluegrass especially used in golf courses. We analyzed data from the seed certification standards of three states (Washington, Idaho and Oregon) in U.S.A. The certification processes both field inspection and laboratory requirement satisfying the minimum seed quality standards. The seed harvesting field must be propagated with the specified class of seeds and requires an adequate isolated distance from other crops. Moreover, the field should be clean and free from the objectionable weeds. The seed analysis tests include a germination rate, a percentage of pure seed, contents of other crop seed, weed seed, and inert matter. The certification standards of the certified seed and the sod quality seed showed general similarity in all three states. The certification standards of the sod quality seed should have less than 0.02% of maximum weed seed. The certified seed should have less than 0.3% of maximum weed seeds. Those certification standards of seed quality should guaranty the quality of turfgrass establishment of golf course.

• Korean Journal of Soil Science and Fertilizer
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• v.33 no.3
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• pp.145-152
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• 2000

The total acreage of 4,894ha of upland soils in Yeongyang area, the main crop cultivated were red-pepper. They were distributed mainly on local valleys and alluvial fans(54.9%), about 61.2% had 7~15% slopes, and about 73.2% had fine loamy family in soil texture. the soils were classified into Ochrepts(73.7%). Udalfs(16.9%), Fluvents(6.2%) and Psamments(3.2%) etc. The upland soils with 100~250m in altitude and "moderately well drained" had higher contents in inorganic nutrients. The red-pepper Produced in the high altitude(>400m) were lower in quality and yields, while the content of sugar and yields of pepper produced in fine loamy textured soils were higher than other soil textures. The yields of red-pepper produced in the "moderately well drained" soils which had better water supply capacity were higher than "well drained" soils.

• Korean Journal of Agricultural and Forest Meteorology
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• v.22 no.4
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• pp.250-257
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• 2020

It is difficult for farmers to select new crops for cultivation to increase income. So we conducted land suitability assessment of grapes with soil and climate information related to crop growth. At first, land suitabilities for grapes were classified into three categories (most suitable, suitable, low productive & not suitable areas) according to soil and climate conditions, respectively. In details, land suitability with respect to soil was assessed by soil morphological and physical properties including soil texture, drainage class, available soil depth, slope and gravel content, whereas one in accordance with climate was evaluated by average annual temperature, temperature during the growing season, temperature during maturation, the lowest temperature, chilling requirement and precipitation during the growing season. Secondly, we combined both soil and climate classification results using a most-limiting characteristic method. Maps showing the suitable land for grapes cultivation were drawn. The results indicate that the most suitable area of cultivation for grapes in south Korea was 3.43% and suitable (possible) area was 10.61%. This study may help to preserve land and increase the productivity through providing valuable information regarding where more suitable areas for grapes are located.

• Journal of Appropriate Technology
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• v.6 no.2
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• pp.136-145
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• 2020

Agriculture is the backbone of the economy of most developing countries. In these countries, agriculture or farming is mostly done manually with little integration of machinery, intelligent systems and data monitoring. Irrigation is an essential process that directly influences crop production. The fluctuating amount of rainfall per year has led to the adoption of irrigation systems in most farms. The absence of smart sensors, monitoring methods and control, has led to low harvests and draining water sources. In this research paper, we introduce a 433 MHz Radio Frequency and 2G based Smart Irrigation Meter System and a water prepayment system for rural areas of Tanzania with no reliable internet coverage. Specifically, Ngurudoto area in Arusha region where it will be used as a case study for data collection. The proposed system is hybrid, comprising of both weather data (evapotranspiration) and soil moisture data. The architecture of the system has on-site weather measurement controllers, soil moisture sensors buried on the ground, water flow sensors, a solenoid valve, and a prepayment system. To achieve high precision in linear and nonlinear regression and to improve classification and prediction, this work cascades a Dynamic Regression Algorithm and Naïve Bayes algorithm.