• 농촌계획
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• 제29권4호
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• pp.175-182
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• 2023

The purpose of this study, the trend of renewable energy, domestic and foreign renewable energy policies, and the flow of the legal system related to renewable energy location were identified, and a location analysis using public data was studied when solar energy was located. First, renewable energy is leading to energy conversion by reducing the proportion of existing fossil fuel-centered energy sources in the global trend and increasing the proportion of renewable energy, an eco-friendly energy source, and changing the institutional and market structure. Second, large-scale solar energy power plants are installed and operated in rural areas where there is no change in insolation and land prices are cheaper than in urban areas where there are many changes in insolation due to surrounding high-rise buildings and street trees. Third, if a preliminary location review is conducted using public data at this time, it will be easy to identify the optimal location for area and size calculation. Fourth, the solar energy location functional area was studied in area A, and the total area of the target area was 624.5km², with 392.7km² and 62.9% of the avoidance area where solar power cannot be located.

• 대한환경공학회지
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• 제27권7호
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• pp.753-761
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• 2005

전처리 공정에 따른 투과 flux 변화를 살펴보면 $MIEX^{(R)}$+UF 공정의 경우 응집+UF 공정에 비하여 높은 유기물 제거율을 나타내었으나 투과 flux 감소는 크게 나타났다. 따라서, 막 오염을 자세하게 규명하기 위하여 sequential filtration 실험결과 막 오염물질은 고분자 유기물질로 나타났으며, DOC 0.5 mg/L 이하의 유기물질이 막 오염 유발물질로 작용하고 있었다. 10 kDa 이하의 저분자 유기물질들은 $MIEX^{(R)}$ 처리에 의해 제거가 용이하여 막 표면에서 유기물 부하를 감소시켜 이로 인해 응집+UF공정에 비하여 투과 flux 감소율이 낮게 나타났다. $MIEX^{(R)}$+UF공정은 입자상 물질의 존재 유무에 관계없이 flux 감소율은 거의 유사한 경향을 보였으나 응집+UF공정은 용존성 유기물질만이 존재하는 시수에 비하여 입자상 물질이 존재하는 경우에 투과 flux 감소가 더 낮게 나타났다.

• 유기물자원화
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• 제15권1호
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• pp.123-133
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• 2007

항생제 사용의 증가와 무분별한 사용으로 인한 항생제 오남용은 항생제 내성균 증가와 더불어 미생물 종의 변화 및 수질환경에 독성물질로써 작용할 수 있다. 특히 항생제는 생물학적 폐수처리 공정에서 미생물에 의한 하 폐수 처리의 효율성 문제를 가져올 수 있다. 본 연구에서는 축산업에서 가장 많이 사용되는 항생제로 조사된 Oxytetracycline(OTC) 항생제가 축산폐수의 생물학적 처리과정에서 질산화와 유기물 제거효율에 미치는 영향을 살펴보았다. 항생제가 축산폐수의 처리효율에 미치는 영향을 살펴보기 위해서 회분식 시험과 $A_2/O$(Anoxic-Anoxic-Oxic) 시스템을 이용하였다. 향후 항생제를 다량 함유하고 있는 축산폐수를 처리할 수 있는 축산폐수처리시스템에 대해서 연구하고자 한다.

• 한국정보과학회논문지:컴퓨팅의 실제 및 레터
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• 제14권6호
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• pp.609-613
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• 2008

대형 시스템은 각 컴포넌트가 여러 다른 개발자에 의하여 개발된다. 개발 과정에서 컴포넌트간의 인터페이스 관리의 효율성은 전체 개발 효율에 큰 영향을 미친다. 특히, 개발 초기 과정에서는 컴포넌트가 새롭게 정의되거나 변경되는 경우가 많다. 컴포넌트의 새로운 정의나 변경은 컴포넌트간의 인터페이스의 생성이나 변경을 필요로 한다. 이러한 인터페이스의 변경에 대한 관리가 효율적으로 이루어지지 않는 경우, 관련된 컴포넌트를 개발하는 서로 다를 개발자들이 서로 다른 인터페이스를 기반으로 개발을 진행하는 경우가 발생한다. 이는 개발의 효율이 저하되는 문제를 일으킨다. 이러한 문제를 해결하기 위하여 메시지 관리시스템은 메시지 기반의 인터페이스 관리를 위한 수단을 제공한다. 또한, 메시지에 대한 코드 생성을 통하여 구현의 편의성을 제공해 주며, 메시지 관리 시스템 내에 정의된 메시지 정보를 이용하여 인터페이스 설계 명세서(IDD)를 자동으로 생성해 준다. 문서 자동 생성은 메시지 변경으로 인한 실제 인터페이스와 문서와의 불일치를 방지한다. 또한, 메시지 관리 시스템은 전체 시스템의 각 컴포넌트 간 메시지를 관리함으로써 각 컴포넌트 간 메시지 흐름에 대한 종합적인 정보를 수집하는 것이 가능하다. 이러한 정보는 컴포넌트간 메시지 흐름의 병목 현상의 발생을 미리 방지하거나. 전체 시스템 성능의 조율을 지원하는데 응용할 수도 있다.

• 한국가금학회지
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• 제10권1호
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• pp.1-22
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• 1983

The Purpose of this study is to examine both supply and demand side of broiler chicken in Korea. Especially the paper aims to investigate the broiler chicken production Dressing and marketing pattern which may affect the demand for it. It is generally understood that broiler chicken production becomes unstable because of frequent market price fluctuation mainly due to disequilibrium of quantities demanded ana supplied It is important to point out that marketing in the form dressed chicken has been enforced by the regulation in Seoul area since March 1st, 1983, though live birds have been customarily marketed for year. It is assumed that the subsituation of chicken meat for beef would save foreign exchanges, because increasingly large amount of beef is imported mainly thanked to a chronical shortage in local production. Main findings of this study may be summarized as follows: 1) Broiler chicker production has been rapidly increased recently, estimating 180-200 million head per year with the trend of contineous increase year after year. Price fluctuation during the year is found, especially summer and winter mainly due to seasonal demand change. It is known that mal-funconing of broiler chicken market may be one of the causes for a large Price fluctuation. Accordingly the increase of marketing efficiency may reduce the price fluctuation and also positively impact on creating demand for the chicken consumption. 2) It is also interesting to note that 90 percent of broilers are grown on the floor and almost 86 percent of total broilers composed of so called high-bros, weighing on an average more than 1.6kg per head Approximately 8 weeks are required for of around marketing birds at the feed efficiency of around 2.3-2.5 Average broiler farm raises between 1,000 and 2,000 head, showing a quite small scale of operation. Only a few sampled farmers follow an all-in and all-out method in broiler production.

• 한국수소및신에너지학회논문집
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• 제33권6호
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• pp.845-855
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• 2022

In response to climate change, the world is continuing efforts to reduce fossil fuels, expand renewable energy, and improve energy efficiency with the goal of achieving carbon neutrality. In particular, R&D is being made on the value chain covering the entire cycle of hydrogen production, storage, transportation, and utilization in order to shift the energy supply system to focus on hydrogen energy. Hydrogen-based energy sources can produce heat and electricity at the same time, so it is possible to utilize heat energy, which can increase overall efficiency. In this study, calculation of the optimal scale for hydrogen-based cogeneration and the composition of heat sources were reviewed. It refers to a method of the optimal heat source size according to the external heat supply and heat storage to be considered. The results of this study can be used as basic data for establishing a hydrogen-based energy supply model in the future.

• 전자공학회논문지CI
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• 제47권1호
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• pp.160-170
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• 2010

본 논문은 Haar 웨이브릿변환과 평균 박스필터에 기반을 둔 Haar 웨이브릿 특징 검출자를 제안한다. 원 영상을 Haar 웨이브릿 변환을 통해 분해하여 영상의 분산정보를 얻고 영상 식별을 위한 특징정보를 추출한다. 영역을 나타내는 주위영역들 중에 분산이 가장 큰 영역의 관심점을 검출하기 위하여 국부 분산정보를 비교하는 평균 박스필터를 적용하고 빠른 계산을 위한 적분영상 기법을 사용한다. Haar 웨이브릿 변환과 평균 박스필터를 이용하여 제안한 검출자는 밝기 변화, 스케일 변화, 영상의 회전에 민감하지 않는 특성을 제공할 수 있다. 실험결과는 제안한 방법이 적은 관심점을 사용하는 경우에도 기존의 DoG 검출자와 Harris corner 검출자에 비해 더 높은 repeatability와 효율성 그리고 매칭정확성을 달성할 수 있음을 보여준다.

• 한국물환경학회지
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• 제23권6호
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• pp.843-849
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• 2007

Monitoring of NOM characteristics is important for improving removal efficiency of natural organic matter (NOM) in water treatment processes. In this study, several NOM characteristics, which include specific UV absorbance (SUVA), total carbonate content, molecular weight distribution, and fluorescence properties, were measured using samples collected from a pilot-scale water treatment plant consisting of coagulation/flocculation (C/F), filtration, ozonation and granular activated carbon (GAC) processes. The highest removal of NOM was observed in C/F and filtration processes as demonstrated by the reduction of dissolved organic carbon (DOC) by 25% and 21%, respectively. Despite nearly no change in DOC, however, the lowest SUVA value and the highest total carbohydrate content were observed in the sample from ozonation process. This indicates that non-degradable aromatic compounds become depleted and biodegradable organic compounds are enriched during the process. Comparison of synchronous fluorescence spectra of the samples showed that ozoation process increased protein-like fluorescence while it decreased fulvic-like and terrestrial humic-like fluorescence. Consistently, a slight peak of protein-like fluorescence was observed in the sample from ozonation process. The greatest change in molecular weight distributions of the samples was observed in C/F process. Comparison of size exclusion chromatogram of the samples revealed that NOM fractions with the molecular weight greater than 2000 Da were reduced by over 90% after C/F process. SUVA values and total carbohydrate content of the samples were well correlated with a ratio of protein-like fluorescence and terrestrial humic-like fluorescence intensities with the correlation coefficients of 0.99 and 0.91, respectively. This suggests that synchronous fluorescence properties of NOM could be used as useful tolls for monitoring changes of some NOM characteristics during water treatment processes.

• KEPCO Journal on Electric Power and Energy
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• 제2권1호
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• pp.103-108
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• 2016

Carbon Capture and Storage technologies are recognized as key solution to meet greenhouse gas emission standards to avoid climate change. Although MEA (monoethanolamine) is an effective amine solvent in $CO_2$ capture process, the application is limited by high energy consumption, i.e., reduction of 10% of efficiency of coal-fired power plants. Therefore the development of new solvent and improvement of $CO_2$ capture process are positively necessary. In this study, improvement of $CO_2$ capture process was investigated and applied to Test Bed for reducing energy consumption. Previously reported technologies were examined and prospective methods were determined by simulation. Among the prospective methods, four applicable methods were selected for applying to 0.1 MW Test Bed, such as change of packing material in absorption column, installing the Intercooling System to absorption column, installing Rich Amine Heater and remodeling of Amines Heat Exchanger. After the improvement construction of 0.1 MW Test Bed, the effects of each suggested method were evaluated by experimental results.

• 한국기후변화학회지
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• 제7권3호
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• pp.249-256
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• 2016

Porous $Al_2O_3$ hollow fiber membranes were successfully prepared by dry-wet spinning/sintering method. The SEM image shows that the $Al_2O_3$ hollow fiber membrane consists mostly of sponge pore structure. The contact angle and the breakthrough pressure were $126^{\circ}$ and 1.91 bar, respectively. This results indicate that the $Al_2O_3$ hollow fiber membranes were successfully modified to hydrophobic surface. The hydrophobic modified $Al_2O_3$ hollow fiber membranes were assembled into a membrane contactor system to separate $CO_2$ from a model gas mixture of the flue gas at elevated gas velocity. The $CO_2$ absorption flux was enhanced when the gas velocity increased from $1{\times}10^{-3}$ to $6{\times}10^{-3}$ m/s. Whereas the $CO_2$ absorption flux was decreased with the number of hollow fiber membrane of a module because of the concentration polarization. Furthermore, we developed an lab-scale $Al_2O_3$ hollow fiber membrane contactor modules and their system (i.e., $CO_2$ absorption using the $Al_2O_3$ membrane and monoethanolamine (MEA)) that could dispose of over $0.02Nm^3/h$ mixture gas (15% $CO_2$) with the removal efficiency higher than 95%. The results can be useful in a field of the membrane contactor for $CO_2$ separation, helping to design and extend a equipment.