• Korean Journal of Mathematics
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• 제30권2호
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• pp.413-423
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• 2022

In this paper, we prove some results concerning the zeros of Bi-complex polynomials. These results as special cases include Grace's theorem and related results.

• 농촌지도와개발
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• 제7권2호
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• pp.307-320
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• 2000

Agricultural extension services in Korea need to build new extension system to cope with the digital age and especially with shortage of extension educators which has been originated from the changing status from central to local government. The new trends including development of multi-media, wide-spreading of internet, and advent of internet broadcasting are offering the opportunities for new agricultural extension service. Utilization of agricultural internet broadcasting could be a new alternative for enhancing the efficiency of agricultural extension services. Agricultural internet broadcasting could support decision making of farmers by forwarding unique agricultural data which have been collected, compiled and processed by the Rural Development Administration. Farmers will be able to search useful agricultural data through agricultural internet broadcasting for more efficient farm management and marketing farm products. Agricultural internet broadcasting could utilize more prompt and abundant agricultural technology and management data compiled by the Rural Development Administration, and through this process, agricultural internet broadcasting could compensate the shortage of extension manpower. Through feedback process of agricultural internet broadcasting. farmers will be able to communicate more efficiently with extension educators to increase agricultural production and income. Agricultural Internet broadcasting could be an alternative to prevent farmers from being shunned in the information-based society.

• 농촌지도와개발
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• 제7권1호
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• pp.3-12
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• 2000

Agricultural extension services in Korea began in 1956, and led self sufficiency of rice through the 'Green Revolution' in 1970's, and a year around supply of green vegetables through the 'White/Vinyl Revolution' in 1980s. The developmental stages of agricultural extension services in Korea, in terms of major purposes, observed by the researcher were as follows; 1) Stage of production guidance when increase in production was directly related to increased income of farmers, 2) Stage of management guidance, when agricultural extension were not only concerned in increasing production, but also in management and marketing, and 3) Stage of improved welfare, when extension services put more emphasis on welfare of farmers in terms of quality of life, as well as increased production, management and marketing. Since late 1980s, farmers in Korea realized the fact that increased production may not lead to increased income. because of this, farmers also wanted improvement of management and marketing. Extension changed the identified needs of farmers to new knowledge, information, and technology in their farm business operation including management and marketing. Loosened cooperations among the central, provincial and local levels after localization of extension services since January 1997 should be strengthened. Provincial level monitoring and supervising should be enhanced for more effective agricultural extension services to meet the changing needs of farmers in the future.

• Journal of the Korean Statistical Society
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• 제22권2호
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• pp.353-359
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• 1993

In this note we consider other type of tightness than that of Birkel (1988) and prove an invariance principle for nonstationary associated processes by an application of the central limit theorem of Cox and Grimmett (1984), thus avoiding the argument of uniform integrability. This result is an extension to the nonstationary case of an invariance priciple of Newman and Wright (1981) as well as an improvement of the central limit theorem of Cox and Grimmett (1984).

• Journal of the Korean Statistical Society
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• 제23권2호
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• pp.504-512
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• 1994

A simple proof for the random central limit theorem is given for a family of stationary linear lattice processes, which belogn to a class of 2 dimensional random fields, applying the Beveridge and Nelson decomposition in time series context. The result is an extension of Fakhre-Zakeri and Fershidi (1993) dealing with the linear process in time series to the case of the linear lattice process with 2 dimensional indices.

• Journal of applied mathematics & informatics
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• 제1권1호
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• pp.31-42
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• 1994

In this paper we investigate an functional central limit theorem for a nonstatioary d-parameter array of associated random variables applying the crite-rion of the tightness condition in Bickel and Wichura[1971]. Our results imply an extension to the nonstatioary case of invariance principle of Burton and Kim(1988) and analogous results for the d-dimensional associated random measure. These re-sults are also applied to show a new functional central limit theorem for Poisson cluster random variables.

• 농촌지도와개발
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• 제1권2호
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• pp.147-163
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• 1994

Agricultural extension programs in Korea had focused mainly on increased production, and the biggest pride of extension was the achievement of rice self-sufficency in 1970s and abundant vegetable and animal production in 1980s. Farming in Korea has changed rapidly in recent years and extension system on commercialized crops have not been satisfactorily developed to mete farmers` demands. Facing the emerging challenges of international competition and trade liberalization for agricultural commodities, the goals of extension should be focused on increased income and the welfare of coral communities. The transfering of agricultural extension educator from central government jobs to local ones has emerged recently under the trends of localization which resulted unstable job environment of extension educator. Intensive pre-service and in-service training of extension workers on current and advanced techologies are essential to upgrade the quality of extension services, and the future directions for professional development of agricultural extension educators in Korea were suggested as follows: 1. Establishing a national network on agricultural extension system to promote exchanges of information among counties and provinces, to conduct meetings and to publish information on agricultural extension. 2. Determining the implications of recent national and global trends on agricultural extension, and strenthening communication at local, national and international levels for an effective extension system in the era of localization, internationalization and globalization; 3. Recognizing the effect of number and quality of extension staff on the impact of extension and providing opportunities development and advancement of extension personnel through education, training, incentives and rewards; 4. Giving a higher priority to agricultural extension in national policies in order to ensure the adequacy of budgetary support and recognition of importance of extension by the ministries concerned and mass communications.

• 한국작물학회지
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• 제64권3호
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• pp.176-184
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• 2019

추청벼는 중부평야지의 유기재배에 가장 많이 재배되고 있는 품종이지만 최근 육성된 품종보다 쌀수량, 미질, 병해충 저항성이 약하기 때문에 유기재배에 적합하지 않으므로 유기재배에 적합한 벼 품종을 선정하고자 삼광, 진수미 등 고품질 15 품종을 충북 청주시에 소재한 유기재배 인증 농가포장에서 3년간 시험하여 검토한 연구결과는 다음과 같다. 1. 시험연구포장은 수년간 유기재배를 하여 지력이 좋았기 때문에 관행재배보다 생육이 왕성하여 간장 및 수수가 증가되었다. 대보, 친농과 현품은 등숙비율이 추청벼보다 낮았으나 10 a 당 쌀수량은 9~18% 증수되었다. 2. 3년간 병해충 피해가 많이 발생하지 않았으나 품종별 차이가 있었다. 추청벼와 비교하여 우수한 품종은 이화명충(2 기)은 하이아미, 수광, 대보, 미광, 현품, 친농, 칠보와 진수미, 잎집무늬마름병은 하이아미, 대보, 현품, 칠보와 진수미, 이삭도열병은 청남, 수광, 대보, 미광, 친농, 칠보, 황금누리, 수려진미와 진수미, 벼 키다리병은 하이아미, 미광, 도복은 대보, 미광, 청해진미, 현품, 친농, 칠보, 호평과 황금누리가 강하였다. 3. 단백질함량이 추청벼보다 낮은 품종은 청남, 수광, 대보, 삼광, 현품, 친농, 칠보, 호평, 황금누리, 수려진미와 진수미로 7% 미만이었고, 특히 수광과 삼광은 6% 미만으로 우수하였다. 백도는 수광, 대보, 삼광, 진수미가 40 이상으로 추청벼보다 높았다. 기계적 식미치는 대보, 수광, 삼광과 진수미가 우수하였고, 완전미율은 현품, 수광, 삼광, 대보와 진수미가 높았다. 4. 최고 및 최종점도는 삼광, 미광과 칠보가 높았고, 치반점도는 현품이 가장 높았다. 수려진미, 청남, 삼광, 대보와 수광은 -20 이상이기 때문에 저장 시 노화가 더디게 진행될 것으로 판단되었고, 호화온도는 수광, 대보, 삼광과 진수미가 가장 낮았다. 5. 이상의 결과 중부평야지 유기재배에서 많이 재배되고 있는 추청벼를 대체하기 위한 품종은 수량성, 식미특성 및 병해충저항성을 고려해 볼 때 '삼광', '진수미', '대보'가 적합할 것으로 판단되었다.

• Asian-Australasian Journal of Animal Sciences
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• 제12권3호
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• pp.422-428
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• 1999

The mineral status of native goats and forage species, namely; Cynodon plectostachyus, Pennisetum purpureum. Eleusine indica, Cynodon dactylon, Calopogonium muconoides, Centrosema pubescens, Leucaena leococephala, and Mimosa pudica in lahar affected areas of Concepcion, Tarlac, Philippines were determined. Forage and blood samples were collected six times in 1996-97, and analyzed for calcium, phosphorus, magnesium, sulfur, copper, iron, molybdenum, selenium, and zinc. Forage calcium and sulfur are non-limiting. Most species had low phosphorus, copper and selenium, while some had magnesium and zinc levels lower than the critical limit because of low mineral content and high percolation rate of lahar deposits. Iron and molybdenum were in excess. The effect of seasonal variation was observed only in copper, sulfur and iron. Average blood mineral concentration of the animals was above critical limit, but there were no significant differences between seasons. All the animals had plasma phosphorus and magnesium above critical level; but 20 % had low copper, zinc and selenium especially in dry season possibly due to insufficient amount of these elements and excessive molybdenum and iron in most forage. Conversely, calcium in forage was high; but 40 % of the animals had low plasma calcium concentration. Although no clinical signs of mineral deficiencies were observed, supplemental feeding would be important since the condition of the pasture in lahar-laden areas is not expected to improve in the next five years. Intensified use of L. leucocephala with better mineral profile would be ideal.

• 농촌지도와개발
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• 제7권1호
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• pp.101-119
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• 2000

Agricultural Extension Services in Korea have accomplished a significant role in self- sufficiency of rice, a national staple food, through green revolution in 1970's; supplying green vegetables even during the winter season through white revolution in 1980's; and establishing technical agriculture by organizing rural leaders and 4-H members. In 1990s changes were made in international situations under the Uruguay Round multilateral trade negotiations and inauguration of the World Trade Organization. This was followed by localization of the extension staffs and the functions of extension services in Korea changed dramatically from national government to local governments. Thus, a weakened national function resulted in loosening of the linkages of research and extension in central government and local extension offices. Difficulties were reported in diffusion of new agricultural technology and efficient management of extension personnel. Developmental tasks for better extension services for the 21st century in Korea would include recovering national functions of agricultural extension, and developing a new paradigm for extension service. This should include the following measures; 1) Cooperative extension service should be adapted to involve national as well as local governments and non-government organization. 2) The target groups for extension services should be expanded to include farmers, noel residents as well as urban consumers. 3) The role of the extension service should cover agricultural technological diffusion of innovations as well as managerial skills and leadership development for rural organizations. 4) Extension services should be introduced to small farmers as well as consultation services for advanced farms. Diversified approaches should be employed for mama effective services. 5) Pre-service as well as in-service education should be offered to secure better extension educators equipped with knowledge, understanding and abilities on agricultural technology, information, agricultural philosophy, instructional methods and communication skills.