• 한국유기농업학회지
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• 제22권4호
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• pp.593-610
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• 2014

The whole world concentrates on the reduction of greenhouse gas to effectively cope with policy toward global climate change. To effectively react to climate change, even the agricultural sector requires construction of new farming systems that utilizes new and renewable energy because of rising oil prices and regulations for greenhouse gas emissions. For this reason, we need to fuse the new and renewable energy with the horticulture sector of which the light and heat energy cost accounts for great part, moreover, efforts and researches should me done which can increase income of farmers through reducing carbon dioxide and energy cost in agricultural production expenses. Therefore, this study analyzes economic feasibility and applicability of fusing geothermal heat pump and solar power facilities with high-tech glass greenhouse. As a result, it is concluded that there surely are an applicability and economic feasibility if we apply new development system that can be an alternative for problems of securing premises of existing geothermal heat pump and the RPS system as a power generation company in case of solar power. Therefore, using this analysis data, if new empirical studies fusing and implementing agriculture sector with new and renewable energy fields proliferate and be applied to actual rural and agricultural field, it will increase actual income and will become a new advanced agricultural system that effectively deals with world-wide environmental problems.

• Asian-Australasian Journal of Animal Sciences
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• 제32권5호
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• pp.748-756
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• 2019

Objective: The objective of this study was to examine the effect of using a tunnel ventilation system within the dairy barn environment upon the productivity of dairy cows during the winter season. Methods: The study was performed at the University Farm, Faculty of Agriculture, Utsunomiya University. Twenty-one Holstein dairy cows (5 heifers and 16 multiparous) were enclosed in a stall barn. Unventilated (UV) and tunnel-ventilated (TV) was operated by turns every other week, and a number of key parameters were measured in the barn, including tunnel ventilation output, temperature, relative humidity, gas concentrations (oxygen [$O_2$], carbon dioxide [$CO_2$], and ammonia [$NH_3$]). Also, skin and rectal temperature, respiratory rate, blood gas concentrations, and bacterial count were measured from nipple attachments on ten cows. The amount of fodder left uneaten, and general components and somatic cell count of the milk were measured. Results: As for our dairy barn environment, air temperature dropped significantly with the passage of time with TV. Humidity was significantly higher with TV at 0600 h compared to UV, while $CO_2$ and $NH_3$ concentrations with UV were significantly higher than with TV at 0000 h and 0600 h. Skin temperature was significantly lower with TV compared to UV at 0000 h and 0600 h. Respiratory rate was also significantly lower at 0600 h with TV than with UV. Bacterial count for the nipple attachments was significantly lower with TV than with UV at 0600 h. The amount of leftover fodder was significantly less with TV in comparison with UV. Conclusion: Our results suggest that a TV system in the winter barn results in environmental improvements, such as reductions in unfavorable gas concentrations and bacterial growth. Consequently, it is expected that barns utilizing a TV system will be beneficial for both animal health and production.

• 한국가금학회:학술대회논문집
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• 한국가금학회 2004년도 제21차 정기총회 및 학술발표회
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• pp.53-68
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• 2004

Eggshell quality is one of the most important factors that influence hatchability. The porosity and overall quality of eggshell have a very significant effect on exchange of vital gas (carbon dioxide and oxygen) between the developing embryo and the air during incubation. Thin-shelled eggs showed the greater weight loss than do thick-shelled eggs. causing the chick to have difficulty in hatching. Thin-shelled eggs also have a much greater chance of being cracked during handling. On the other hand. thick-shelled eggs showed the higher hatchability as a result of greater fertility and lower intermediate and late embryonic mortalities. Even a small percentage improvement in the eggshell quality could result in significant saving to the breeder industry in an increasingly competitive environment. Many factors including nutrition. management practices, environmental conditions and breeding are known to be related to eggshell quality. In this review brief accounts of each factor associated with eggshell quality and hatchability were provided. We conducted three experiments to investigate the effects of dietary Ca. vitamin D3 metabolite and some bioactive materials on eggshell quality and hatching egg production. The results of our studies showed that relatively high levels of dietary Ca in combination with 25-hydroxycholecalciferol had beneficial effects on improving eggshell quality and reproductive performances in aged egg-type breeder hens. It was also suggested that the proper use of some feed additives such as isoflavon and chitosan might provide means of improving eggshell quality and reproductive performances in aged egg-type breeder hens.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2009년도 하계학술발표대회 논문집
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• pp.1312-1316
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• 2009

Growing interest in $CO_2$ capturing from industrial processes and storage in underground formations is emerging from commitments in reducing $CO_2$ emissions manifested in the Kyoto Protocol. In this paper, $CO_2$ liquefaction system is treated in focus of liquefaction efficiency & production rate. Presently $CO_2$ is transported in ships or trucks at a pressure of 14-20 bar. Considering this, the liquefaction pressures of 20, 15, 6.5 bar are selected. Compressor work and cooling capacity are calculated and compared. In order to investigate the effect of intercooling, the compressed gas after compressor work is cooled by ambient air or seawater. In case of applying the intercooling to the system, consuming energy can be saved larger than 20%. In the lower liquefaction pressure, the more $CO_2$ can be obtained due to higher density. In the liquefaction pressure of 6.5 bar, its $CO_2$ production is about 35% higher than that of the system with the liquefaction pressure, 20 bar.

• Journal of Animal Science and Technology
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• 제60권11호
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• pp.27.1-27.8
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• 2018

Background: Enteric methane ($CH_4$) accounts for about 70% of total $CH_4$ emissions from the ruminant animals. Researchers are exploring ways to mitigate enteric $CH_4$ emissions from ruminants. Recently, nano zinc oxide (nZnO) has shown potential in reducing $CH_4$ and hydrogen sulfide ($H_2S$) production from the liquid manure under anaerobic storage conditions. Four different levels of nZnO and two types of feed were mixed with rumen fluid to investigate the efficacy of nZnO in mitigating gaseous production. Methods: All experiments with four replicates were conducted in batches in 250 mL glass bottles paired with the ANKOM$^{RF}$ wireless gas production monitoring system. Gas production was monitored continuously for 72 h at a constant temperature of $39{\pm}1^{\circ}C$ in a water bath. Headspace gas samples were collected using gas-tight syringes from the Tedlar bags connected to the glass bottles and analyzed for greenhouse gases ($CH_4$ and carbon dioxide-$CO_2$) and $H_2S$ concentrations. $CH_4$ and $CO_2$ gas concentrations were analyzed using an SRI-8610 Gas Chromatograph and $H_2S$ concentrations were measured using a Jerome 631X meter. At the same time, substrate (i.e. mixed rumen fluid+ NP treatment+ feed composite) samples were collected from the glass bottles at the beginning and at the end of an experiment for bacterial counts, and volatile fatty acids (VFAs) analysis. Results: Compared to the control treatment the $H_2S$ and GHGs concentration reduction after 72 h of the tested nZnO levels varied between 4.89 to 53.65%. Additionally, 0.47 to 22.21% microbial population reduction was observed from the applied nZnO treatments. Application of nZnO at a rate of $1000{\mu}g\;g^{-1}$ have exhibited the highest amount of concentration reductions for all three gases and microbial population. Conclusion: Results suggest that both 500 and $1000{\mu}g\;g^{-1}$ nZnO application levels have the potential to reduce GHG and $H_2S$ concentrations.

• 한국수소및신에너지학회논문집
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• 제13권2호
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• pp.101-109
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• 2002

This work was focused on the thermal decomposition of methane into hydrogen and carbon black without emitting carbon dioxide. Extensive experimental investigation on the thermal decomposition of methane has been carried out using a continuous flow reaction system with tubular reactor. The experiments were conducted at the atmospheric pressure condition in the wide range of temperature ($950-1150^{\circ}C$) and flow rate (250 - 1500 ml/min) in order to study their dependency on hydrogen yield. During the experiments the carbon black was successfully recovered as an useful product. Undesirable pyrocarbon was also formed as solid film, which was deposited on the inside surface of tubular reactor. The film of pyrocarbon in the reactor wall became thicker and thicker, finally blocking the reactor. The design of an efficient reactor which can effectively suppress the formation of pyrocarbon was thought to be one of the most important subjects in the thermal cracking of methane.

• Asian-Australasian Journal of Animal Sciences
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• 제29권12호
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• pp.1805-1811
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• 2016

The goal of this study was to estimate the emissions of greenhouse gases (GHG), namely methane ($CH_4$), nitrous oxide ($N_2O$), and carbon dioxide ($CO_2$) from poultry and pig production in South Korea over the last 10 years (2005 through 2014). The calculations of GHG emissions were based on Intergovernmental Panel on Climate Change (IPCC) guidelines. Over the study period, the $CH_4$ emission from manure management decreased in layer chickens, nursery to finishing pigs and gestating to lactating sows, but there was a gradual increase in $CH_4$ emission from broiler chickens and male breeding pigs. Both sows and nursery to finishing pigs were associated with greater emissions from enteric fermentation than the boars, especially in 2009. Layer chickens produced lower direct and indirect $N_2O$ emissions from 2009 to 2014, whereas the average direct and indirect $N_2O$ emissions from manure management for broiler chickens were 12.48 and $4.93Gg\;CO_2-eq/yr$, respectively. Annual direct and indirect $N_2O$ emissions for broiler chickens tended to decrease in 2014. Average $CO_2$ emission from direct on-farm energy uses for broiler and layer chickens were 46.62 and $136.56Gg\;CO_2-eq/yr$, respectively. For pig sectors, the $N_2O$ emission from direct and indirect sources gradually increased, but they decreased for breeding pigs. Carbon dioxide emission from direct on-farm energy uses reached a maximum of $53.93Gg\;CO_2-eq/yr$ in 2009, but this total gradually declined in 2010 and 2011. For boars, the greatest $CO_2$ emission occurred in 2012 and was $9.44Gg\;CO_2-eq/yr$. Indirect $N_2O$ emission was the largest component of GHG emissions in broilers. In layer chickens, the largest contributing factor to GHG emissions was $CO_2$ from direct on-farm energy uses. For pig production, the largest component of GHG emissions was $CH_4$ from manure management, followed by $CO_2$ emission from direct on-farm energy use and $CH_4$ enteric fermentation emission, which accounted for 8.47, 2.85, and $2.82Gg-CO_2/yr$, respectively. The greatest GHG emission intensity occurred in female breeding sows relative to boars. Overall, it is an important issue for the poultry and pig industry of South Korea to reduce GHG emissions with the effective approaches for the sustainability of agricultural practices.

• 원예과학기술지
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• 제33권5호
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• pp.675-686
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• 2015

아스파라거스는 수확 후 품질변화가 심하여, 보존 전에 1-MCP 등의 전처리를 통하여 상품성 유지효과를 검정하고자 하였다. 아스파라거스를 1-MCP 및 CEPA 처리 후 $7^{\circ}C$에 저장하면서 에틸렌과 $CO_2$ 발생 등을 관찰하였다. 또한 저장전 처리에 따라 발생되는 에틸렌 및 $CO_2$ 발생량을 측정방법에 따라 연속적인 방법과 비연속적인 방법으로 측정하였다. 아스파라거스 유통 중 불량환경을 가정한 CEPA 처리에 의해 에틸렌 가스 발생 및 호흡 특성이 달라지는데 1-MCP와의 혼용처리로 에틸렌의 영향을 상쇄시키는 것으로 나타났다. CEPA 처리는 에틸렌 및 $CO_2$ 가스 발생이 증가하며, 1-MCP 혼용처리로 인해 발생량이 감소하였고 1-MCP 단용처리는 무처리에 비해 에틸렌 발생에 큰 차이가 없었으나, $CO_2$ 발생량을 다소 감소시키는 것으로 나타났다. $CO_2$ 발생에서 연속측정(flow-system)이 비연속적 측정보다 변화 경향이나 처리간의 차이가 명확히 나타났다. 형태적이나 생체중량, 가용성고형물, 삼투몰 농도에 있어서 1-MCP는 CEPA에 의한 영향을 경감시키는 효과는 있었으나, CEPA 처리와 같이 외생적인 에틸렌과 조우하지 않는다면 무처리에 비해서는 큰 효과를 보이지 못하였다. 아스파라거스에서 1-MCP 처리는 불량 환경조건에서 발생되는 외생 에틸렌의 영향을 상쇄시킬 수 있을 것으로 보였으며, 전처리를 통한 상품성 유지가 기대된다.

• 한국가스학회지
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• 제22권1호
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• pp.26-36
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• 2018

기존 건식 개질 반응에 사용되는 니켈 기반 촉매 공정은 활성화 온도가 높고, 촉매 표면의 활성점에 탄소 침착 및 금속 소결 현상 등의 문제점이 있다. 이에 본 연구에서는 촉매공정에 DBD 플라즈마 공정이 결합된 촉매+플라즈마 공정을 이용하여 뷰테인 건식 개질 반응 특성을 조사하고 기존 촉매 공정과 비교 분석하였다. 촉매의 특성을 파악하기 위해 비표면적 분석기, XRD, SEM 및 TEM 등을 사용하여 물리 화학적 특성을 조사 하였다. $580^{\circ}C$에서 $10%Ni/{\gamma}-Al_2O_3$촉매를 사용한 경우 촉매+플라즈마 공정의 경우 촉매 단독 공정에 비해 이산화탄소와 뷰테인 전환율이 각각 27%, 39%향상되었다. 촉매+플라즈마 공정의 경우 플라즈마에 의해 생성된 다양한 활성종의 영향으로 이산화탄소와 뷰테인 전환율 및 생성되는 수소 농도가 증가하였으며, 뷰테인 건식 개질 반응 과정에서 플라즈마에 의해 니켈 촉매의 크기가 감소하고 분산도가 증가하여 반응 효율이 향상되는 것으로 판단되었다.

• 공업화학
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• 제22권3호
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• pp.301-307
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• 2011

Spirulina platensis NIES 39의 최적 배양 조건을 확립하고자 본 연구에서는 여러 광원에 따른 균체의 생장양상을 확인하여 보았다. 이를 기반으로 형광등 및 LED 광생물반응기를 개발하여 균체농도 증가, 이산화탄소 고정화속도 및 효율, 클로로필 생산에 대한 연구를 수행하였다. 배양에 공급되는 이산화탄소 농도 및 유속은 명 조건에서 약 4 h 주기로 10 min간 5% $CO_2$, 0.1 vvm임이 확인되었다. 내부조사형 형광등 광원 및 저전력형 SMD 타입 적색광 LED 광생물반응기는 최대 배양 건조 균체량이 1.411 g/L를 넘지 못하였지만, 조도를 높인 파워형 적색광 LED (색온도 12000 K)에서는 최대 건조 균체량이 1.758 g/L가 되었다. 이 경우 이산화탄소 고정화 속도 및 효율 또한 증가되었다. 총 클로로필 생산량은 균체량 증가에 비례하여 증가하였지만, 건조균체질량당 생산량은 청색광 LED조건(색온도 7500 K)에서 더 높은 수치를 보여주었다. 그리고 최대 균체생장조건(DCW)에서 이산화탄소 농도는 주입량(5% $CO_2/Air$, v/v) 대비 유실률은 0.15% 이내로 확인되었다.