• Asian-Australasian Journal of Animal Sciences
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• 제18권8호
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• pp.1088-1097
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• 2005

Main objectives of this study were to investigate accuracy, bias and power of linear and threshold model segregation analysis methods for detection of major genes in categorical traits in farm animals. Maximum Likelihood Linear Model (MLLM), Bayesian Linear Model (BALM) and Bayesian Threshold Model (BATM) were applied to simulated data on normal, categorical and binary scales as well as to disease data in pigs. Simulated data on the underlying normally distributed liability (NDL) were used to create categorical and binary data. MLLM method was applied to data on all scales (Normal, categorical and binary) and BATM method was developed and applied only to binary data. The MLLM analyses underestimated parameters for binary as well as categorical traits compared to normal traits; with the bias being very severe for binary traits. The accuracy of major gene and polygene parameter estimates was also very low for binary data compared with those for categorical data; the later gave results similar to normal data. When disease incidence (on binary scale) is close to 50%, segregation analysis has more accuracy and lesser bias, compared to diseases with rare incidences. NDL data were always better than categorical data. Under the MLLM method, the test statistics for categorical and binary data were consistently unusually very high (while the opposite is expected due to loss of information in categorical data), indicating high false discovery rates of major genes if linear models are applied to categorical traits. With Bayesian segregation analysis, 95% highest probability density regions of major gene variances were checked if they included the value of zero (boundary parameter); by nature of this difference between likelihood and Bayesian approaches, the Bayesian methods are likely to be more reliable for categorical data. The BATM segregation analysis of binary data also showed a significant advantage over MLLM in terms of higher accuracy. Based on the results, threshold models are recommended when the trait distributions are discontinuous. Further, segregation analysis could be used in an initial scan of the data for evidence of major genes before embarking on molecular genome mapping.

• Journal of Biosystems Engineering
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• 제32권1호
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• pp.30-36
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• 2007

Geothermal heat pump systems use the earth as a heat source in heating mode and a heat sink in cooling mode. These systems can be used for heating or cooling systems in farm facilities such as greenhouses for protected horticulture, cattle sheds, mushroom house, etc. A horizontal type means that a geothermal heat exchanger is laid in the trench buried in 1.2 to 1.8 m depth. Because a horizontal type has advantages of low installation, operation and maintenance costs compared to a vertical type, it is easy to be adopted to agriculture. In this study, to heat and cool farm facilities and obtain basic data for practical application of horizontal geothermal heat pump systems in agriculture, a horizontal geothermal heat pump system of 10 RT scale was installed in greenhouse. Heating performance of this system was estimated. The horizontal geothermal heat pump used in this study had heating COP of 4.57 at soil temperature of 14$^{\circ}C$ for depth of 1.75m and heating COP of 3.75 at soil temperature of 7$^{\circ}C$ for the same depth. The stratification of water temperature in heat tank appeared during the whole heat rejection period.

• 한국농업기계학회:학술대회논문집
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• 한국농업기계학회 1996년도 International Conference on Agricultural Machinery Engineering Proceedings
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• pp.263-269
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• 1996

In indian agricultural , the energy use pattern has played dominant role in influencing the level of mechanization . Besides that the agro-climatic factors as well as the size of holdings do affect the degree of mechanization . Nearly 30 percent of total cultivated area is owned by l76 percent of the small and tiny land holders each owning even less than a hectare. On the other hand, about 2 percent of land owners cultivate land. These variabilitieshave greatly influenced the ownership of power sources on Indian farms. Small farmers, employ human and animal energies with the use of hand tools and animal drawn equipments. Whereases, the use of tractors, power tillers, electric motors, etc. on small farms is on a marginal scale. There are few pockets and also extensive wheat growing regions where mechanical and electrical power sources are extensively used in production agriculture leading to about 185% of cropping intensity . In that region, the animal energy is employed for on the farm transport of fertilizers, fodders and fuel to support milch animals and other household activities . Inspite of high degree of mechanization, the harvesting of crops is done by human labour with few exceptions of harvesting wheat crops by combines in few pockets. In overall assessment of mechanization, the following conclusions are drawn : ⅰ) Farm operation which show a growing trend of mechanization are (a) tillge, (b) seedling (c) Irrigation (d) Plant protection application (e) Threshing and (f) Transport . ⅱ) Crop cultivation system in respect of wheat, maize and sorghum have been greatly mechanized. ⅲ) The least mechanized cropping systems are (a) vegetable production and (b) cultivation of sugarcane, cotton, rice and pulses. ⅳ) Annual production of tractor has touched the figure of 280.000 by 1995 and the total number has crossed 1.5million on Indian farms.

• 환경생물
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• 제35권4호
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• pp.677-683
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• 2017

The Korean aquaculture industry was generally began in the 1970s and has gradually increased. Now, the number of households is about 7,068 and the scale of an aquaculture farm is about 248,014 ha; the value of all production in the industry is estimated to be about 1602.2 billion won. The aquaculture industry is very valuable and important for future food resources. However, the aquaculture industry was damaged by several marine ecological disturbance causing organisms. The Ascdiella aspersa colonized on the shell of scallop and then scallops were detached from rope. The patterns of damage in the aquacultures were observed in Tongyeong (oyster), Geojedo (oyster), and Gangneung (sea squirt) in June, 2017, as well as in Tongyeong (oyster) in November, 2017 by SCUBA divers. The species Halichondria bowerbanki, Bugula neritina, Mytilus galloprovincialis, Balanus amphitrite, Ascidiella aspersa, Ciona intestinalis, Didemnum sp, Styela plicata in Tongyeong, M. galloprovincialis, A. aspersa, C. intestinalis, D. vexillum, S. plicata in Geojedo, and M. galloprovincialis in Gangneung were all usually found in their farms. The marine ecological disturbance causing organisms gave rise to a reduced number of aquaculture products.

• 한국농공학회논문집
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• 제63권4호
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• pp.43-53
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• 2021

The purpose of this study is to analyze the factor influencing in order to increase the intention to revisit rural experience tourism. 181 men and women who had experienced rural experience tourism were surveyed in a Self-Assessment Questionnaire. Some farming experience, life experience, cultural experience, and leisure experience were set as independent variables as representative programs of rural experience tourism, satisfaction and trust as mediated variables, and relationships as dependent variables. Here, the relationship is regarded as a variable representing the intention to revisit. When performing multi-group path analysis by separating men and women, both men and women had a statistically significant positive (+) effect in the Leisure experience→Satisfaction path and the Trust→Relation path. In addition, the paths that were statistically significant for women were not statistically significant, but were statistically significant only for men were Farm experience→Satisfaction path, Farm experience→Relation path, and Leisure experience→Relation path. In addition, the paths that were not statistically significant for men, but statistically significant for women were Culture experience→Satisfaction and Trust→Satisfaction. According to this study, in order to increase the intention to revisit, both men and women should consider leisure experience. And men should emphasize farming experience, while women should emphasize cultural experience. It is considered that there is a need to further subdivide leisure experience, farming experience and cultural experience for the region. This study has a limitation of only 181 people. More large-scale research will be possible in the future.

• Asian-Australasian Journal of Animal Sciences
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• 제20권8호
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• pp.1305-1318
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• 2007

On a global scale agriculture and in particular enteric fermentation in ruminants is reported to produce about one fourth (21 to 25%) of the total anthropogenic emissions of methane ($CH_4$). Methane is produced during the anaerobic fermentation of hydrolyzed dietary carbohydrates in the rumen and represents an energy loss to the host besides contributing to emissions of greenhouse gases into the environment. However, there appears to be uncertainty in the $CH_4$ estimation from livestock due to the limited availability of data to document the variability at the farm level and also due to the significant impact of diet on the enteric $CH_4$ production. The methane mitigation strategies require robust prediction of emissions from rumen. There are many methods available which would be suitable for measuring $CH_4$ produced from the various stages of animal production. However, several factors need to be considered in order to select the most appropriate technique like the cost, level of accuracy required and the scale and design of the experiments to be undertaken. Selection of any technique depends on the accuracy as each one has its advantages and disadvantages. Screening of mitigation strategies may be evaluated using individual animal before large-scale trials on groups of animals are carried out. In this review various methods for the estimation of methane production from ruminants as well as for the determination of methane production potential of ruminant feeds are discussed. The advantages and disadvantages of the methods starting from respiration chamber, ventilated hood, facemask, sulphur hexafluoride ($SF_6$) tracer technique, prediction equations and meteorological methods to in vitro methods are detailed.

• 대한지역사회영양학회지
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• 제3권5호
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• pp.739-747
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• 1998

The purpose of this study was to compare the dietary habit and nutrient intakes of Korean farmers according to their different family patterns and farming types. Food and nutrient intakes were obtained by food frequency method. The subjects(male 35%, female 65% : mean age, $48{\pm}11 years)$ were compared 46% of nuclear family, 59% of 3-4 person of family size ; 50% of middle-scale farming ; 54% of rice farming. Sixteen percent were over 60 years old group. In aspects of dietary habit, farmers of medium size farming and 10-20 years of farming experience frequently skipped meals. But their appetite was better than small farm famers. Dinner irregularity was more frequent in their group of 3-4 person families. The numbers of food intake were significantly different according to family pattern. Nuclear family groups consumed more kinds of foods. The mean energy intake was 2000Kcal/day, with PFC ratio of 19 : 16 : 65. The energy and nutrient intakes showed the same tendency as the food variety. Intakes of calcium and iron were lower than the Korean RDA. Families with over 5 people consumed higher amounts of protein and minerals. Intakes of thiamin, niacin, and vitamin E were better in large families and large-scale farming groups. As compared with the PMS ratio, the level of monounsaturated fatty acids as higher than saturated FA. The lipid intake was also better in large families and large-scale farming. The results suggest that dietary habit and nutrient intakes were different by family pattern and farming types.

• 한국산림과학회지
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• 제88권3호
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• pp.309-319
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• 1999

본 연구는 산림 시업에 따른 풍치 관리 정보를 파악하고자 수행하였다. 대상 임분은 현재 산림무육작업 요구도가 높은 낙엽송 인공림을 대상으로 하였다. 촬영된 임분 사진의 모의조작을 통하여 산림작업별로 구분된 35매의 임분 경관이 이용되었다. 각 경관은 신뢰성 검정을 통해 얻은 3개 집단, 전체 593명의 평가 자료를 이용하여 분석하였다. 시각 선호도 평가는 1 - 10 point 평점값을 이용하였다. 이들 평점값의 보정은 RMRATE의 SBE 분석 프로그램을 통해 실시되었다. 시각 선호도와 이미지 척도와의 관련 정도를 비교하기 위해 13매의 간벌 임분을 대상으로 어의 구별척을 이용하여 공간 이미지를 측정하였다. 일반적으로 무육 전의 자연 임분 보다는 작업 후의 쾌적하고 질서 정연한 임분을 높게 선호하고 있었다. 시각 선호도는 나지 면적과 폐잔재 면적이 증가할수록 감소하였으며 임목 밀도, 지하고, 지피식생과 높은 관련이 있었다. 소규모 개별지의 벌구 모양은 곡선보다는 직선 모양을 선호하고 있었다. 시각 선호도는 응답자의 사회경제적 변수에 따라 유의적 차이가 있었다. 연구 결과들은 산림풍치관리를 위한 시업 수행 방법을 제시하고 있다.

• 대한지리학회지
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• 제29권3호
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• pp.340-359
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• 1994

This study intends to describe the characteristics of the transformation of the rural society by tracing the changing social and economic processes of traditional clan villiage (Yeolmi-ri, Silchon-myeon, Kwangju-gun, Kyunggi-province) in the suburbs of Seoul Metropolitan Area. Rural society has experienced serious change of the social structure by the ever expanding urbanization and industrialization since 1960's. The suburbs of Seoul Metropolitan Area is the representative case area of such transformation. This study analyzed various chracteristics of population structure of a villiage, the processes of residential movement and the occupational shift of each household of the villiage in terms of household's life-history collected by interviewing with each household. And the whole households of a villiage is divided by two groups of the native clan group and the non-dan in-migrant group. The results of this study are summarized as follows. 1) This villiage is located within a lineal distance of 40km and a time distance of about 30 to 40 minutes, adjoined dy the Joongbu(중부) national highway, the Kyungchoong (경충) industrial road, the local road between Yangpyuna(양평) and Gonjiam(곤지암) and having a advantageous iocational linkage to Seoul capital city. 2) It is a typical traditional dan villiae constituted of dan family Gu(구) one of whose ancestors had appointed to the prime minister of Chosun Dynasty, and until 1979, 56 out of 60 families of the villiage households were clan families. 3) Since 1979, as the villiage invaded by the out-movement of the small scale manufacturing industries from Seoul capital city, labours moved in this vallige from outside and increased villiage size up to 203 households in 1993, consequently the constitutional proportion between the native clan group and the non-clan in-migrant group was reversed up to 28% vs 72% deepening the sociological heterogeneity. 4) Because of the small scale of industries in this villiage and the vicinity with the city of Seoul, the population turnover of this villiage is very high. The turnover frequency is firstly high within same administrative district of gun(군) level and secondly high between this villiage and the city of Seoul. Thus short-distance movement is identified. 5) There is a close correlation between the residential movement and the occupational shift. The most numbers of non-farm native group have the experiences of migration while the members of native farming group don't shift both the job and the place of residence. The inmigrant group had several migration experiences but few occupational shifts. Thus occupatioanl shift is high for the native group while residential shift is high for the in-migrant group. It is concluded that the change proceeded in Metropolitan suburbs was not directed to form the traditional rural village as 'gesund Gebiet' with respect to the ballance among the economic, cultural and environmental adequency.

• 대한지리학회지
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• 제31권3호
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• pp.558-576
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• 1996

1978년 이후 중국은 농촌지역의 개혁을 통해 개혁. 개방이 시작되었다. 인민공사의 집체경제 체제에서, 농가를 단위로 하는 '가정연산승포제'로 변화하여 노동 의욕이 고취되고 생산성의 증가를 이루었다. 하지만 1980년대 이후 생산의욕 유인 효과가 줄어들고, 보다 확대된 시장 메카니즘에 적합하지 못한 토지이용 방식으로 농업생산의 정체와 노동력의 비농업으로의 이전 과정을 겪었다. 이에 농가의 수요에 맞춘 새로운 토지제도가 필요하게 되어, 流轉의 확대, 토지의 생활보호 기능과 상업적 기능을 동시에 만족시키는 兩田制, 토지의 분산성을 극복하여 토지 생산의 능률을 높이려는 規模經營, 토지 소유관계의 불명확성을 극복하려는 股役合作制(주식제), 열등한 토지의 개간과 이용을 위한 '四荒' 경매 등의 제도가 시행되었다. 이러한 정책은 중국의 전반적인 시장경제의 도입으로 인한 농촌지역의 적응과정으로 이해할 수 있다. 그 시행으로 급격한 변화를 피하면서도 기존의 모순을 해결할 수 있었으며, 특히 지역적 차이에 따라 정책은 상이하게 전개된 것이 특징이다.