• International Journal of Industrial Entomology and Biomaterials
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• 제17권1호
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• pp.115-120
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• 2008

Recently, there has been the gradual growth of the public in rural amenities, hobby farming works, much more urbanities, and especially near-retires. However, in spite of popular preference to ruralities, little has been known about their demand on retired rural life. Therefore, this study examined urbanites' attitude to preparatory works for out-migration, preferred residential site condition and life styles in the countryside. For the purpose, data were collected from the survey with the sample of 62 urban trainees who were studying farming technology in department of training on agricultural technology of Korea National Agricultural College, RDA. We carried out the experience farming to candidate with using the abandoned sericultural facilities which are the silkworm rearing house and mulberry fields. The 71% of urban trainees, who answered in this survey, hoped to move into countryside after retirement and to make a monthly income of $1,000 from agriculture. The age distribution of sericulural farmers is about 79% more than that of 60 years old. In the experience farming works. The two candidates made 1,977$ with net income through 32 days worked in spring season. In autumn season, the couple candidates made 1,317$ with net income through 23 days worked. Knowledge of these results will be important to policy-makers and to understand the role that retirement in-migration play in stimulating economic growth of rural agricultural farmers.

• 한국수산과학회지
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• 제10권4호
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• pp.259-265
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• 1977

굴 양식장의 환경연구중 거제만양식장의 밀도 및 노화정도에 관한 기초조사를 1977년 6월부터 11월까지 6개월간에 걸쳐 실시하였다. 1. 거제만해역의 면적은 $48.87km^2$이고 도수산국에 등록된 이 해역내의 양식장 수면적은 $10.91km^2$이다. 해역면적에 대한 면허면적은 $22.23\%$이고 면허면적과 해역면적의 비는 1 : 4.48이다. 2. 부영양화의 정도를 A,B,C로 구분하여 C단계를 과영양화로의 과도기단계라 할때, 거제만은 양식어장으로서 수질은 A단계로 양호한 편인데 비해 저질은 C단계로 부영양화의 한계치에 도달되었거나 또는 약간 상회하며 과영영화로 진입하고 있다.

• 한국산학기술학회논문지
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• 제10권10호
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• pp.2779-2785
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• 2009

육류 중에 닭은 가장 저렴한 생산비용으로 단백질을 섭취할 수 있는 장점으로 인하여 많은 양이 사육되며 우리나라 식생활의 육류 소비를 늘리는 중요한 가축이다. 생육조건에 악영향을 미치는 여러 요인 중에 축산업에서 가장 대표적인 것은 악취이다. 악취물질은 축분에서 발생되는 암모니아, 아민류, 황화수소 및 머캡탄을 들 수 있으며 악취는 없으나 악영향을 미치는 물질로는 메탄, 질소산화물 등이 있다. 이러한 악취물질에 의하여 가축은 생육에 저해를 받으며, 심한 경우 폐사까지 이르게 된다. 계사의 경우 겨울철에는 난방을 하고 있는 실정임에도 불구하고 나머지 계절과 같이 환기를 통하여 악취를 제어하고 있다. 겨울철의 경우 대부분의 계사가 등유를 사용하는 온풍기를 이용하여 난방을 하고 있으나 계사내의 유해한 암모니아의 농도가 높아지므로 인하여 환기를 시키고 있는 실정이다. 따라서 본 연구과제에서는 기존에 사용되고 있는 온풍기에 복합촉매시스템을 접합하여 계사 및 축사의 암모니아 등의 유해 가스를 제어할 수 있는 시스템에 사용될 촉매를 개발하였으며, Mn과 Pt-Rh을 최적의 조성으로 도출하였다.

• 상하수도학회지
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• 제26권1호
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• pp.107-113
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• 2012

Pollutants in aquaculture system effluent mostly originated from solid wastes including uneaten feed and excreta of cultured species. In this research, DAF(Dissolved Air Flotation) unit is suggested as an integrated solid control unit especially as a form of IIBG(Inline Injection Bubble Generation) process in aquaculture system. Solid removal performance of DAF unit was examined under various operation and salinity conditions with turbidity and suspended solid. Solid waste removal efficiencies were found to be affected by operation conditions including saturator pressure, recycle ratio, coagulant concentration. Solid removal efficiency was higher under higher saturator pressure and recycle ratio under which condition larger number of bubbles is generated. Coagulant is thought to have important role in creating bubble-particle aggregate by showing better removal efficiency with higher concentration. However higher saline water showed less effectiveness in removing solids by DAF(IIBG). Application of DAF(IIBG) process also showed additional effect in phosphate removal and DO(Dissolved Oxygen) supply. Phosphate existed in polluted water was removed up to 46% after treatment, which is thought to attribute to aluminium phosphate precipitation. And DO concentration was found to increase over 50% of initial saturation concentration after the injection of micro-bubbles. Through experiments on solid removal from aquaculture effluent, DAF(IIBG) process is estimated to be effective solid control method. This property can help aquaculture system being installed and operated simply and effectively.

• 한국양식학회지
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• 제9권2호
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• pp.109-115
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• 1996

우리나라 연안성에서 가장 중요한 양식대상종의 하나인 참전복의 표식 방류효과에 관한 조사는 보고된 바 없는 실정이다. 따라서 본 연구는 우리 배양장에서 자체 생산된 참전복의 표지 방법별 효과를 검토하고, 방류효과를 구명함으로서 연안 자원의 증강을 도모 하고자 1994년 11월 10일 부터 1995년 3월 30일까지 조사한 결과를 요약하면 다음과 같다. 1. 참전복의 표지 및 표시 방법별 효과는 Al-teco에 의한 표지 부착이 가장 좋았다. 2. 실내 사육에 의한 표지의 탈락 및 폐사율은 각각 $6.7\%$ 및 $8.3\%$였고, 표지에 의한 폐사는 없었다. 3. 실내 사육 및 방류한 표지 개체는 실험 개시시 각구 공히 평균각장 및 전중량이 1.0 cm, 0.092 g 이던 것이 실험종료시에는 각각 1.80cm, 0.74 g, 1.68 cm, 0.68 g으로 성장하였다. 4. 재포된 모든 개체의 분포 중심 수심은 2.6m 였다. 재포된 모든 개체의 평균 이동 거리는 2.6m 였다. 6. 어획사망계수, 자연사망계수 및 전사망계수의 추정치는 각각 0.0195, 0.4652, 0.4847였다.

• 한국양식학회지
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• 제20권3호
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• pp.178-183
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• 2007

Saddleback clownfish, Amphiprion polymnus의 자치어의 생존율 향상을 목적으로 Artemia nauplii 섭식량, 사육수조의 색깔과 염분을 달리한 조건에서 자치어의 성장과 생존율을 비교 조사하였다. 사육수조에 따른 성장과 생존율 조사에서 성장은 검정색 수조와 투명수조에서 사육한 자어가 흰색과 파란색수조에서 보다 성장이 빨랐다. 생존율은 흰색과 투명수조에서 파란색과 검정색 수조에서 보다 높았다. 부화 후 5일째부터 17일째 자어(Total length $5.1{\sim}10.0mm$)에 Artemia nauplii를 50개체/$0.5L{\sim}700$개체/0.5L 범위로 공급한 결과 일일섭식량은 36.8개체(부화 후 5일째)${\sim}$429.3개체(부화 후 17일째)였다. 그리고 염분 내성조사에서 32 psu부터 7일 간격으로 5 psu씩 하강시킨 경우 실험 16일째 22 psu에서 급격히 폐사개체가 늘어나 실험 22일째 전 개체가 폐사하였고 3일 간격으로 2 psu씩 하강시킨 경우 실험 27일째 16 psu에서 전 개체가 폐사하였다.

• 한국응용곤충학회지
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• 제17권4호
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• pp.187-191
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• 1978

본 실험은 끝동매미충의 온도와 일장조건에 따른 발육도 및 증식능력을 조사하여 실내 대양사육에 적합한 온도와 일장의 범위를 밝히고 나아가 온도와 발육속도와의 함수관계를 유도하는데 필요한 기초자료를 얻고자 수행하여 다음과 같은 결과를 얻었다. 1. 비교적 고온조건인 $33^{\circ}C$와 $35^{\circ}C$에서 약충의 발육이 빠르a 우화율이 높았으나 변온처리($28^{\circ}C$와$319{\circ}C$ 각 12시간)에서는 발육이 지연되었다. 2. 성충의 산란력은 고온$(35^{\circ}C)$)에서 약충기를 거친 성충은 산란수가 매우 적었으나 $29^{\circ}C$에서 우화한 성충은 고온$(33^{\circ}C)$에서 많은 산란을 하였다. 3. $29^{\circ}C$에서의 일장은 약충의 발육 및 우화율에 큰 영향을 미치지 못했다. 4. 약충의 발육속도는 $29^{\circ}C$까지는 온도가 상승함에 따라 직선적으로 빨라졌으나 고온$(33-35^{\circ}C)$에서는 증가율이 둔화되는 결과를 얻었다. 5. 이상의 결과로 적합한 사육조건은 약충기에 $27-29^{\circ}C$, 성충기에 $33^{\circ}C$인 것으로 생각된다.

• Journal of Forest and Environmental Science
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• 제25권1호
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• pp.43-48
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• 2009

Forests render both a home and a livelihood for people living in and around them. To reconcile the need of local communities with conservation, the Nishorgo Support Project (NSP or Nishorgo) is supporting co-management in five protected areas of Bangladesh, including Rema-Kalenga Wildlife Sanctuary. The main focus of this study is to assess the effectiveness of alternate income generating activities (AIGAs) which is provided by the Nishorgo Support Project. It is a tool for reducing dependence on forest resources by people living in and around Rema-Kalenga Wildlife Sanctuary and also play effective role in forest conservation. This study compares the socioeconomic condition (income, living style etc.) and forest dependency before and after implementation of co-management activities in Rema-Kalenga Wildlife Sanctuary. A total of 11 villages (sampling intensity was 31%) namely Kalibari, Mongoliabari, Chokidarbari, Chonbari, kalenga, Krishnochura, Hatimara, Himalia, Rashidpur, Goramchori and Horinmara were studied. We surveyed 272 households in these villages (Incase of households survey, sampling intensity was 100%). Data analysis shows that the major income generating livelihood activities were agro farming (30%), followed by fuelwood collection (22.50%), nursery raising (12.5%), cattle rearing (10%), fisheries (7.50%) and others. Study also reveals that after being implementation of the co-management activities the average income levels of the studied villages have rises on 578 Tk/households (1US$ = 70 Taka, Taka means Bangladeshi currency). Further more, many of the illegal loggers became forest protector, which make their life more secured. It was also found that peoples of the study villages are now actively engaging in forest management activities and it is the only hope for conservation and restoration of forest resources not only in Rema-Kalenga Wildlife Sanctuary but also in other protected area's of our country.

• Asian-Australasian Journal of Animal Sciences
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• 제31권11호
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• pp.1714-1720
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• 2018

Objective: This study was conducted to analyze the effects of stocking density on growth and carcass quality, and behavior of Hanwoo cattle to conform with global trends, targeting animal welfare production through the practice of environmentally friendly condition. Methods: Thirty six steers were randomly assigned to three treatment groups (C: 5 heads, T1: 4 heads, T2: 3 heads) and reared in separate pens with a constant stocking density of $50m^2$ (C: $10m^2/head$, T1: $12.5m^2/head$, T2: $16.67m^2/head$) per group from 12 to 30 month of age. Growth performance, behavior and carcass quality traits of each steer were recorded and compared between the treatment groups. Results: In general, the average daily gain during the fattening period was lower in group T2 than in T1 and the control groups. However, carcass weight and dressing percentage was lower in the control group than in T1 or T2 groups (p<0.05). Also, marbling score at 30 months of age was the lowest in the control group (p<0.05), while the three heads group (T2) had the greatest longissimus muscle area and marbling score (p<0.05). The behavior of walking time was the greatest in T2 group, while self-grooming and fighting occurred with the most frequency in the control group (p<0.05). Conclusion: Our results show that the steers in more spacious stocking density had better carcass quality and wellbeing related behaviors, indicating that a lower density has a positive effect on raising management and carcass quality. Thus it is a need to install appropriate pens fitted to welfare-oriented management practices from growing to fattening period in Hanwoo cattle.

• 한국수산과학회지
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• 제51권1호
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• pp.54-63
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• 2018

We investigated the effect of $CO_2$ exposure on the reproductive process of chameleon goby Tridentiger trigonocephalus. Rearing aquaria were exposed for 90 days to $CO_2$ gas through diffuser connected with pH controller maintaining at pH 7.2 ($156.31{\pm}7.90ppm$) in low treatment, and at pH 6.5 ($274.17{\pm}6.51ppm$) in high treatment. $CO_2$ treatment had no significant effects on survival rates although the value was decreased compared to the controls. In female fish, $CO_2$ treatment had no significant effects on gonadosomatic index (GSI), hepatosomatic index (HSI) and condition factor (CF). However, high $CO_2$ treatment decreased HSI and CF in males significantly compared to the controls (P<0.05). The spawning occurrence was 6 times in the low level $CO_2$ treatment, and 4 times in the high level $CO_2$ treatment although only once in the controls. For the histological observations, there was no significant difference in $CO_2$ treatments. However, in male fish, $CO_2$ treatment delayed the formation of sperm from spermatid compared to controls. These results suggest $CO_2$ may disrupt reproductive process by delaying gametogenesis in chameleon goby and it was more sensitive in males.