• Title/Summary/Keyword: Renewable technology

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Definition and Division in Intelligent Service Facility for Integrating Management (지능화시설의 통합운영관리를 위한 정의 및 구분에 관한 연구)

  • PARK, Jeong-Woo;YIM, Du-Hyun;NAM, Kwang-Woo;KIM, Jin-Young
    • Journal of the Korean Association of Geographic Information Studies
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    • v.19 no.4
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    • pp.52-62
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    • 2016
  • Smart City is urban development for complex problem solving that provides convenience and safety for citizens, and it is a blueprint for future cities. In 2008, the Korean government defined the construction, management, and government support of U-Cities in the legislation, Act on the Construction, Etc. of Ubiquitous Cities (Ubiquitous City Act), which included definitions of terms used in the act. In addition, the Minister of Land, Infrastructure and Transport has established a "ubiquitous city master plan" considering this legislation. The concept of U-Cities is complex, due to the mix of informatization and urban planning. Because of this complexity, the foundation of relevant regulations is inadequate, which is impeding the establishment and implementation of practical plans. Smart City intelligent service facilities are not easy to define and classify, because technology is rapidly changing and includes various devices for gathering and expressing information. The purpose of this study is to complement the legal definition of the intelligent service facility, which is necessary for integrated management and operation. The related laws and regulations on U-City were analyzed using text-mining techniques to identify insufficient legal definitions of intelligent service facilities. Using data gathered from interviews with officials responsible for constructing U-Cities, this study identified problems generated by implementing intelligent service facilities at the field level. This strategy should contribute to improved efficiency management, the foundation for building integrated utilization between departments. Efficiencies include providing a clear concept for establishing five-year renewable plans for U-Cities.

Fuel characteristics of Yellow Poplar bio-oil by catalytic pyrolysis (촉매열분해를 이용한 백합나무 바이오오일의 연료 특성)

  • Chea, Kwang-Seok;Jeong, Han-Seob;Ahn, Byoung-Jun;Lee, Jae-Jung;Ju, Young-Min;Lee, Soo-Min
    • Journal of the Korean Applied Science and Technology
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    • v.34 no.1
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    • pp.1-11
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    • 2017
  • Bio-oil has attracted considerable interest as one of the promising renewable energy resources because it can be used as a feedstock in conventional petroleum refineries for the production of high value chemicals or next-generation hydrocarbon fuels. Zeolites have been shown to effectively promote cracking reactions during pyrolysis resulting in highly deoxygenated and hydrocarbon-rich compounds and stable pyrolysis oil products. In this study, catalytic pyrolysis was applied to upgrade bio-oil from yellow poplar and then fuel characteristics of upgraded bio-oil was investigated. Yellow Poplar(500 g) which ground 0.3~1.4 mm was processed into bio-oil by catalytic pyrolysis for 1.64 seconds at $465^{\circ}C$ with Control, Blaccoal, Whitecoal, ZeoliteY and ZSM-5. Under the catalyst conditions, bio-oil productions decreased from 54.0%(Control) to 51.4 ~ 53.5%, except 56.2%(Blackcoal). HHV(High heating value) of upgraded bio-oil was more lower than crude bio-oil while the water content increased from 37.4% to 37.4 ~ 45.2%. But the other properties were improved significantly. Under the upgrading conditions, ash and TAN(Total Acid Number) is decrease and particularly important as transportation fuel, the viscosity of bio-oil decreased from 6,933 cP(Control) to 2,578 ~ 4,627 cP. In addition, ZeoliteY was most effective on producing aromatic hydrocarbons and decreasing of from the catalytic pyrolysis.

Effects of Dietary Protein Level on Velvet Antler Production in Red Deer(Cervus elaphus) (사료의 단백질 수준이 Red Deer(Cervus elaphus)의 녹용생산에 미치는 영향)

  • Jeon, B.T.;Moon, S.H.;Hudson, R.J.
    • Journal of Animal Science and Technology
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    • v.45 no.4
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    • pp.577-584
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    • 2003
  • Three dietary treatments were compared over two years to determine the effects of dietary protein levels and feeding patterns on velvet production in red deer (Cervus elaphus). The LL group received a 13% protein diet whereas the HH group received a 19% protein diet. The LH group switched from the low to high protein diet at the time of antler casting. Significant relationships were found between velvet production and the girth and length of main beam (p<0.01), daily growth rate of velvet (p<0.01), body weight at cutting time (p<0.05 in 1998 and p<0.01 in 1999), date of casting (p<0.01), and body weight and velvet production of the previous year (p<0.05 in 1998 and p<0.01 in 1999). Different levels of protein in diets in this study did not show statistically significant different effects in general. The girth of velvet, summed for top, middle and bottom of the main beam, tended to be thickest in HH for two years and thinnest in LL for 1998 and in LH for 1999. The main beam tended to be longest in HH at 46.3cm in 1998 and 45.2cm in 1999 and shortest in LH at 39.9cm in 1998 and 41.5cm in 1999. Velvet fresh weight tended to be highest in HH at 2,600$\pm$1,000g in 1998 and 3,038$\pm$867g in 1999 and lowest in LH at 2,287$\pm$826g in 1998 and 2,739$\pm$1,079g in 1999. Daily growth rate of velvet antler tended to be greatest in HH (43$\pm$16g/day in 1998 and 51$\pm$14g/day in 1999) and least in LH (38$\pm$15g/day in 1998 and 45$\pm$18g/day in 1999).

Optimization of Microalgae-Based Biodiesel Supply Chain Network Under the Uncertainty in Supplying Carbon Dioxide (이산화탄소 원료 공급의 불확실성을 고려한 미세조류 기반 바이오 디젤 공급 네트워크 최적화)

  • Ahn, Yuchan;Kim, Junghwan;Han, Jeehoon
    • Korean Chemical Engineering Research
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    • v.58 no.3
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    • pp.396-407
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    • 2020
  • As fossil fuels are depleted worldwide, alternative resources is required to replace fossil fuels, and biofuels are in the spotlight as alternative resources. Biofuels are produced from biomass, which is a renewable resource to produce biofuels or bio-chemicals. Especially, in order to substitute fossil fuels, the research focusing the biofuel (biodiesel) production based on CO2 and biomass achieves more attention recently. To produce biomass-based biodiesel, the development of a supply chain network is required considering the amounts of feedstocks (ex, CO2 and water) required producing biodiesel, potential locations and capacities of bio-refineries, and transportations of biodiesel produced at biorefineries to demand cities. Although many studies of the biomass-based biodiesel supply chain network are performed, there are few types of research handled the uncertainty in CO2 supply which influences the optimal strategies of microalgae-based biodiesel production. Because CO2, which is used in the production of microalgae-based biodiesel as one of important resources, is captured from the off-gases emitted in power plants, the uncertainty in CO2 supply from power plants has big impacts on the optimal configuration of the biodiesel supply chain network. Therefore, in this study, to handle those issues, we develop the two-stage stochastic model to determine the optimal strategies of the biodiesel supply chain network considering the uncertainty in CO2 supply. The goal of the proposed model is to minimize the expected total cost of the biodiesel supply chain network considering the uncertain CO2 supply as well as satisfy diesel demands at each city. This model conducted a case study satisfying 10% diesel demand in the Republic of Korea. The overall cost of the stochastic model (US$ 12.9/gallon·y) is slightly higher (23%) than that of the deterministic model (US$ 10.5/gallon·y). Fluctuations in CO2 supply (stochastic model) had a significant impact on the optimal strategies of the biodiesel supply network.

Evaluation on Heating Effects of Geothermal Heat Pump System in Farrowing House (지열 난방시스템을 이용한 분만돈사의 난방효과 분석)

  • Choi, H.C.;Park, Jae-Hong;Song, J.I.;Na, J.C.;Kim, M.J.;Bang, H.T.;Kang, H.G.;Park, S.B.;Chae, H.S.;Suh, O.S.;Yoo, Y.S.;Kim, T.W.
    • Journal of Animal Environmental Science
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    • v.16 no.3
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    • pp.205-215
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    • 2010
  • Geothermal heat pump system (GHPS) is an energy-efficient technology that use the relatively constant and renewable energy stored in the earth to provide heating and cooling. With the aim of using GHPS as a heating source, it's possibilities of application in farrowing house were examined by measuring environmental assessment and sow's performance. A total of 96 sows were assigned to 2 pig housings (GHPS and conventional housing) with 48 for four weeks in winter season. During the experimental period, indoor maximum temperature in GHPS-housing was measured up to $26.7^{\circ}C$, average temperature could maintain $21.2^{\circ}C$. The mean value of dust levels and $CO_2$, $NH_3$ and $H_2S$ gas emissions were decreased in GHPS-housing compare with those of conventional housing. Litter size, birth weight, parity and weaning weight did not differ between housings. However, feed intake of sow in GHPS-housing was lower than that of conventional housing. In energy consumption for heating, electric power consumption increased in GHPS-housing than the conventional housing, a 2,250 kwh increase, whereas there is no fuel usage for heater in GHPS-housing. Amount of ground water circulated for heating in cold weather for earth heat exchanger was 8.4-12.9 ton per day. In conclusion, GHPS may have environmental benefits and effectiveness of heating in farrowing housing and affect the performance in sows.

Recent Progress in Air Conditioning and Refrigeration Research: A Review of Papers Published in the Korean Journal of Air-Conditioning and Refrigeration Engineering in 2006 (공기조화, 냉동 분야의 최근 연구 동향: 2006년 학회지 논문에 대한 종합적 고찰)

  • Han, Hwa-Taik;Shin, Dong-Sin;Choi, Chang-Ho;Lee, Dae-Young;Kim, Seo-Young;Kwon, Yong-Il
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.20 no.6
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    • pp.427-446
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    • 2008
  • A review on the papers published in the Korean Journal of Air-Conditioning and Refrigeration Engineering in 2006 has been accomplished. Focus has been put on current status of research in the aspect of heating, cooling, ventilation, sanitation and building environments. The conclusions are as follows. (1) The research trends of fluid engineering have been surveyed as groups of general fluid flow, fluid machinery and piping, etc. New research topics include micro heat exchanger and siphon cooling device using nano-fluid. Traditional CFD and flow visualization methods were still popular and widely used in research and development. Studies about diffusers and compressors were performed in fluid machinery. Characteristics of flow and heat transfer and piping optimization were studied in piping systems. (2) The papers on heat transfer have been categorized into heat transfer characteristics, heat exchangers, heat pipes, and two-phase heat transfer. The topics on heat transfer characteristics in general include thermal transport in a cryo-chamber, a LCD panel, a dryer, and heat generating electronics. Heat exchangers investigated include pin-tube type, plate type, ventilation air-to-air type, and heat transfer enhancing tubes. The research on a reversible loop heat pipe, the influence of NCG charging mass on heat transport capacity, and the chilling start-up characteristics in a heat pipe were reported. In two-phase heat transfer area, the studies on frost growth, ice slurry formation and liquid spray cooling were presented. The studies on the boiling of R-290 and the application of carbon nanotubes to enhance boiling were noticeable in this research area. (3) Many studies on refrigeration and air conditioning systems were presented on the practical issues of the performance and reliability enhancement. The air conditioning system with multi indoor units caught attention in several research works. The issues on the refrigerant charge and the control algorithm were treated. The systems with alternative refrigerants were also studied. Carbon dioxide, hydrocarbons and their mixtures were considered and the heat transfer correlations were proposed. (4) Due to high oil prices, energy consumption have been attentioned in mechanical building systems. Research works have been reviewed in this field by grouping into the research on heat and cold sources, air conditioning and cleaning research, ventilation and fire research including tunnel ventilation, and piping system research. The papers involve the promotion of efficient or effective use of energy, which helps to save energy and results in reduced environmental pollution and operating cost. (5) Studies on indoor air quality took a great portion in the field of building environments. Various other subjects such as indoor thermal comfort were also investigated through computer simulation, case study, and field experiment. Studies on energy include not only optimization study and economic analysis of building equipments but also usability of renewable energy in geothermal and solar systems.

A Management Plan of Wastewater Sludge to Reduce the Exposure of Microplastics to the Ecosystem (미세플라스틱의 환경노출을 최소화하기 위한 하·폐수 슬러지 관리방안)

  • An, Junyeong;Lee, Byung Kwon;Jeon, Byong-Hun;Ji, Min-Kyu
    • Clean Technology
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    • v.27 no.1
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    • pp.1-8
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    • 2021
  • Due to the negative impacts of microplastics (MPs) on the ecosystem, the investigation of its occurrence and its treatment from sewage and wastewater treatment plants (WWTPs) have received a lot of attention in the recent years. Most MPs are precipitated and removed with the sludge during the treatment process. Proper sludge management is immensely necessary to avoid MP exposure in the environment. However, the domestic research on this aspect is limited. This study reviews appropriate sludge management approaches to decrease environmental MP exposure. This can be achieved through investigating sludge generation and treatment, regulation laws and government policy trends with an emphasis on WWTPs. The ratio of sludge in sewage treatment plants has been observed to be highest in recycling followed by incineration and landfills. Recycling is the highest in fuel followed by construction materials and composting. For WWTPs, the highest ratio is in recycling followed by fuel and landfills, and recycling is confirmed in the following order: incineration > after composting > after solidification > earthworm breeding. Treatment approaches that can increase the exposure of MPs to the ecosystem are considered to be used in landfills and agricultural fields. However, this method is not appropriate given the insufficient capacity of domestic landfills and the sufficient supply of existing chemical and animal manure fertilizers. Instead, it would be rational in terms of environmental preservation to expand the use of fuel and energy in connection with the new and renewable energy policy, and to actively seek the use of sub-materials for construction materials. In order to secure the basic data for the effectiveness of future planning and revision of related laws, it is required to perform an in-depth investigation of the sludge supply and demand status along with the environmental and economic effects.

Physicochemical Changes of Swine Manure by the Treatment of Acid and Alkali for Inactivation of Pathogenic Microorganisms (병원성미생물의 불활성화를 위한 산·알칼리처리가 양돈분뇨의 이화학적 성상에 미치는 영향)

  • Kim, Cho-Long;Kim, Soo-Ryang;Kim, Ha-Je;Jeon, Sang-Joon;Han, Ho;Kim, Dong-Kyun;Lee, Myung-Gyu
    • Journal of Animal Environmental Science
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    • v.18 no.3
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    • pp.229-234
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    • 2012
  • Disinfecting contaminated swine manure with FMD (Foot-and-Mouth Disease) and pathogenic viruses is very important for maintaining sanitized environment. However, very few research reported on this subject, especially post-disinfection to utilize the wastes as a renewable resource. This research is carried out to obtain basic information for chemical treatment in FMD SOP (Standard Operating Procedure, Korea) of contaminated swine manure. Using lime, sodium hydroxide, citric acid and hydrochloric acid, described in FMD SOP, the effects of chemical treatments on livestock manure were compared in this paper. Four combinations of alkali-acid treatments and four kinds of acid-alkali combinations were tested to find out the effective method. Total coliform bacteria in contaminated swine manure, $1.6{\times}10^4$ CFU/100 ml, decreased to the range of 1/1000~1/100 in all treatments. Some specific disinfectants increases BOD (Biochemical Oxygen Demand) and EC(Electric Conductivity), especially, alkaline treatments increases ammonia level than acid treatments. These findings suggest that the treatment methods should be considered as an important environmental factor in post-disinfection of contaminated animal manure with pathogenic microorganisms.

Studies on the Main Level-Grading Factors for Establishment of LFQC (Liquid Fertilizer Quality Certification) System of Livestock Manure in Korea (가축분뇨 액비품질인증제도 구축을 위한 목표요소에 관한 연구)

  • Jeon, Sang-Joon;Kim, Soo-Ryang;Kim, Dong-Gyun;Rho, Kyung-Sang;Choi, Dong-Yoon;Lee, Myung-Gyu
    • Journal of Animal Environmental Science
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    • v.18 no.2
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    • pp.111-122
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    • 2012
  • Establishment of the LFQC (Liquid Fertilizer Quality Certification) system is very urgent issue for recycling livestock manure as renewable resources in Korea faced with environmental problem of manure application to land due to intensive livestock farming. In this study, we investigated relevant laws and regulations on livestock manure fertilizer, certifications of eco-friendly agricultural products, government policies on livestock manure management to establish reasonable direction of Korean LFQC (Liquid Fertilizer Quality Certification) system. As a result from this study, the liquid fertilizers in 'LFQC' system could be classified as three levels according to the usage patterns in field; 1st. Individual Farm Level (IFL), 2nd. Joint Farm Level (JFL), and 3rd. Commercial Level (CML). And finally, we found some characteristics in 'Main Level-Grading Factors' of liquid fertilizer such as fertilizing value, harmfulness, stability, uniformity, economic effect, storage potential, commercial value, functionality. Those items were considered to be the key factors for the establishment of 'LFQC' system. More research on 'Evaluation Standards' for concrete guideline and on the 'Main Level-Grading Factors' be needed to complete Korean LFQC system.

Current Status of Sericulture and Insect Industry to Respond to Human Survival Crisis (인류의 생존 위기 대응을 위한 양잠과 곤충 산업의 현황)

  • A-Young, Kim;Kee-Young, Kim;Hee Jung, Choi;Hyun Woo, Park;Young Ho, Koh
    • Korean journal of applied entomology
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    • v.61 no.4
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    • pp.605-614
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    • 2022
  • Two major problems currently threaten human survival on Earth: climate change and the rapid aging of the population in developed countries. Climate change is a result of the increase in greenhouse gas (GHG) concentrations in the atmosphere due to the increase in the use of fossil fuels owing to economic and transportation development. The rapid increase in the age of the population is a result of the rise in life expectancy due to the development of biomedical science and technology and the improvement of personal hygiene in developed countries. To avoid irreversible global climate change, it is necessary to quickly transition from the current fossil fuel-based economy to a zero-carbon renewable energy-based economy that does not emit GHGs. To achieve this goal, the dairy and livestock industry, which generates the most GHGs in the agricultural sector, must transition to using low-carbon emission production methods while simultaneously increasing consumers' preference for low-carbon diets. Although 77% of currently available arable land globally is used to produce livestock feed, only 37% and 18% of the proteins and calories that humans consume come from dairy and livestock farming and industry. Therefore, using edible insects as a protein source represents a good alternative, as it generates less GHG and reduces water consumption and breeding space while ensuring a higher feed conversion rate than that of livestock. Additionally, utilizing the functionality of medicinal insects, such as silkworms, which have been proven to have certain health enhancement effects, it is possible to develop functional foods that can prevent or delay the onset of currently incurable degenerative diseases that occur more frequently in the elderly. Insects are among the first animals to have appeared on Earth, and regardless of whether humans survive, they will continue to adapt, evolve, and thrive. Therefore, the use of various edible and medicinal insects, including silkworms, in industry will provide an important foundation for human survival and prosperity on Earth in the near future by resolving the current two major problems.