• Journal of the Korean association of regional geographers
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• v.11 no.2
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• pp.291-311
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• 2005

The great estate system of the Old World crossed the Atlantic Ocean in the 1500s along with the Spanish Royal Army, mission, merchants, crops and domestic arrivals, landing at the end of the journey in the Middle and South Americas. The latifundio of Spain's Middle Age combined with the environment of the New World to be regenerated in the name of hacienda which bad became tightly roared in the countryside landscape of New Spain by fin-de-colonial period of 1820s. The haciendas were distributed mainly over the central part of the present-dey Mexico, and the presence of water and towns determined the specific location of the large landed estates. Depending on the activities performed, the hacienda can be divided into several types such as grain hacienda, livestock hacienda, mining hacienda, henequen hacienda, and so forth. Consisting of landlords, estate managers and waged labor called peons, the hacienda as a semi-autarkic settlement played various roles as the home of church, the agrarian center and the hearth of cultural diffusion, as well as dwelling. Toward the end of the colonial period the hacienda experienced internal transformations driven by capitalism.

• Korean Journal of Ichthyology
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• v.13 no.4
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• pp.248-253
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• 2001

An histological study was conducted to determine the initial treatment time and treatment duration in the use of sex-reversal hormones in relation to gonadal development and sexual differentiation in the bagrid catfish, Leiocassis ussuriensis. The primordial germ cell, which could be recognized from one-day-old fry, began to protrude into the peritoneal cavity between the mesonephric duct and the gut. The primordial gonad with a genital ridge was developed at 5~10 days after hatching. Sex differentiation of the ovary was identified by the ovarian cavity and meiotic oocytes from 20-day-old larvae. Testicular differentiation was also identified by spermatogonial cells from 20-day-old larvae. It may therefore be concluded that this species belongs to the differentiated type of gonochoristic teleost.

• Korean Journal of Organic Agriculture
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• v.20 no.3
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• pp.411-422
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• 2012

To investigate the possibility of sustainable agriculture in no-tillage pepper this study was carried out in vinyl greenhouse with organic cultivation having no pesticide certification. 1. Growth and yield in pepper cultivation General growth in pepper was suppressed with decreasing hill spacing, primary branch length, and stem width. Fruit diameter and fruit weight in no-tillage increased significantly, and yield of pepper increased by 10% compared with conventional tillage. From results organic cultivation in no-tillage improved a quality of pepper compared with conventional tillage. 2. Production cost of conventional tillage and no-tillage Production cost of conventional tillage and no-tillage was not different in seed cost, inorganic fertilizer cost, pesticide cost, repair cost, light agricultural tool cost, agriculture facilities depreciation cost and so on. Intermediary goods cost in no-tillage was decreased by 11% for organic fertilizer cost, light and heat expenses and power rate, heavy agricultural tool cost, and repairing expenses compare with conventional tillage. Employment effort cost and work effort cost were decreased, and farm income and farm income rate were increased by 11% and 5%, respectively, in no-tillage. In this work, yield and gross income were increased by 10% and 25%, respectively, in no-tillage. Therefore material cost, intermediary goods cost, working expensive, farm income, and income rate were increased by 34%, 3%, 2%, 52% and 22%, respectively.