• Title/Summary/Keyword: energy integration

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Modelling Pasture-based Automatic Milking System Herds: The Impact of Large Herd on Milk Yield and Economics

  • Islam, M.R.;Clark, C.E.F.;Garcia, S.C.;Kerrisk, K.L.
    • Asian-Australasian Journal of Animal Sciences
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    • v.28 no.7
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    • pp.1044-1052
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    • 2015
  • The aim of this modelling study was to investigate the effect of large herd size (and land areas) on walking distances and milking interval (MI), and their impact on milk yield and economic penalties when 50% of the total diets were provided from home grown feed either as pasture or grazeable complementary forage rotation (CFR) in an automatic milking system (AMS). Twelve scenarios consisting of 3 AMS herds (400, 600, 800 cows), 2 levels of pasture utilisation (current AMS utilisation of 15.0 t dry matter [DM]/ha, termed as 'moderate'; optimum pasture utilisation of 19.7 t DM/ha, termed as 'high') and 2 rates of incorporation of grazeable complementary forage system (CFS: 0, 30%; CFS = 65% farm is CFR and 35% of farm is pasture) were investigated. Walking distances, energy loss due to walking, MI, reduction in milk yield and income loss were calculated for each treatment based on information available in the literature. With moderate pasture utilisation and 0% CFR, increasing the herd size from 400 to 800 cows resulted in an increase in total walking distances between the parlour and the paddock from 3.5 to 6.3 km. Consequently, MI increased from 15.2 to 16.4 h with increased herd size from 400 to 800 cows. High pasture utilisation (allowing for an increased stocking density) reduced the total walking distances up to 1 km, thus reduced the MI by up to 0.5 h compared to the moderate pasture, 800 cow herd combination. The high pasture utilisation combined with 30% of the farm in CFR in the farm reduced the total walking distances by up to 1.7 km and MI by up to 0.8 h compared to the moderate pasture and 800 cow herd combination. For moderate pasture utilisation, increasing the herd size from 400 to 800 cows resulted in more dramatic milk yield penalty as yield increasing from c.f. 2.6 and 5.1 kg/cow/d respectively, which incurred a loss of up to $AU 1.9/cow/d. Milk yield losses of 0.61 kg and 0.25 kg for every km increase in total walking distance (voluntary return trip from parlour to paddock) and every one hour increase in MI, respectively. The high pasture utilisation combined with 30% of the farm in CFR in the farm increased milk yield by up to 1.5 kg/cow/d, thereby reducing loss by up to $0.5/cow/d (c.f. the moderate pasture and 800 cow herd scenario). Thus, it was concluded that the successful integration of grazeable CFS with pasture has the potential to improve financial performance compared to the pasture only, large herd, AMS.

An Analysis on the Expert Opinions of Future City Scenarios (미래도시 전망 분석)

  • Jo, Sung Su;Baek, Hyo Jin;Han, Hoon;Lee, Sang Ho
    • Journal of the Korean Regional Science Association
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    • v.35 no.3
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    • pp.59-76
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    • 2019
  • This study aims to develop urban scenarios for future cities and validate the future city scenarios using a Delphi method. The scenarios of future city was derived from urban structure, land use, transportation, and urban infrastructure and development using big data analysis, environmental scanning techniques, and literature review. The Delphi survey interviewed 24 erudite scholars and experts across 6 nations including Korea, USA, UK, Japan, China, Australia and India. The Delphi survey structure was designed to test future city scenarios, verified by the 5-point Likert scale. The survey also asked the timing of each scenario likely happens by the three terms of near-future, mid-future and far-future. Results of the Delphi survey reveal the following points. Firstly, for the future urban structure it is anticipated that urban concentration continues and higher density living in global mega cities near future. In the mid-future small and medium size cities may decrease. Secondly, the land use pattern in the near-future is expected of increasing space sharing and mixed or layered vertical land-use. In addition underground space is likely to be extended in the mid-future. Thirdly, in the near-future, transport and infrastructure was expected to show ICT embedded integration platform and public and private smart transport. Finally, the result of Delphi survey shows that TOD (Transit Oriented Development) becomes a development norm and more emphasis on energy and environment fields.

Degradation of a nano-thick Au/Pt bilayered catalytic layer with an electrolyte in dye sensitized solar cells (염료감응태양전지의 Au/Pt 이중 촉매층의 전해질과의 반응에 따른 열화)

  • Noh, Yunyoung;Song, Ohsung
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.15 no.6
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    • pp.4013-4018
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    • 2014
  • A 0.45 $cm^2$ DSSC device with a glass/FTO/blocking layer/$TiO_2$/N719(dye)/electrolyte/50 nm-Pt/50 nm-Au/FTO/glass was prepared to examine the stability of the Au/Pt bilayered counter electrode (CE) with electrolyte and the energy conversion efficiency (ECE) of dye-sensitized solar cells (DSSCs). For comparison, a 100 nm-thick Pt only CE DSSC was also prepared using the same method. The photovoltaic properties, such as the short circuit current density ($J_{sc}$), open circuit voltage ($V_{oc}$), fill factor (FF), and ECE, were checked using a solar simulator and potentiostat with time after assembling the DSSC. The microstructure of the Au/Pt bilayer was examined by optical microscopy after 0~25 minutes. The ECE of the Pt only CE-employed DSSC was 4.60 %, which did not show time dependence. On the other hand, for the Au/Pt CE DSSC, the ECEs after 0, 5 and 15 minutes were 5.28 %, 3.64 % and 2.09 %, respectively. The corrosion areas of the Au/Pt CE determined by optical microscopy after 0, 5, and 25 minutes were 0, 21.92 and 34.06 %. These results confirmed that the ECE and catalytic activity of Au/Pt CE decreased drastically with time. Therefore, a Au/Pt CE-employed DSSC may be superior to the Pt only CE-employed one immediately after integration of the device, but it would degrade drastically with time.

Quantitative Methodology to Assess Cyber Security Risks of SCADA system in Electric Power Industry (전력 SCADA 시스템의 사이버 보안 위험 평가를 위한 정량적 방법론에 관한 연구)

  • Kang, Dong-Joo;Lee, Jong-Joo;Lee, Young;Lee, Im-Sop;Kim, Huy-Kang
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.23 no.3
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    • pp.445-457
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    • 2013
  • This paper is about the study to build a quantitative methodology to assess cyber threats and vulnerabilities on control systems. The SCADA system in power industry is one of the most representative and biggest control systems. The SCADA system was originally a local system but it has been extended to wide area as both ICT and power system technologies evolve. Smart Grid is a concept to integrate energy and IT systems, and therefore the existing cyber threats might be infectious to the power system in the integration process. Power system is operated on a real time basis and this could make the power system more vulnerable to the cyber threats. It is a unique characteristic of power systems different from ICT systems. For example, availability is the most critical factor while confidentiality is the one from the CIA triad of IT security. In this context, it is needed to reflect the different characteristics to assess cyber security risks in power systems. Generally, the risk(R) is defined as the multiplication of threat(T), vulnerability(V), and asset(A). This formula is also used for the quantification of the risk, and a conceptual methodology is proposed for the objective in this study.

The Demand Survey and Correlational Analysis for Geological Data (지질 자료의 수요조사 및 상관성 분석)

  • Hwang, JaeHong;Chi, KwangHoon;Han, JongGyu;Yeon, YoungKwang;Ryu, Keun Ho
    • Journal of the Korean Association of Geographic Information Studies
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    • v.10 no.1
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    • pp.60-72
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    • 2007
  • In general, the importance of geological information is emphasized not only for national SOC construction, underground space development and energy resources development but also in areas related to environmental disasters such as mine damage, ground subsidence and landslides. Although geological information is highly useful in developing industrial raw materials, national land management and people's welfare, there is no unified governmental institution in charge of collecting and managing geological information in the national level. For this, this paper study: first, to analyze geological demand for common experts; second, to analyze geological demand for public institution; and third, to set priority for geological informatization. In the result of surveying demand for geological information, we need to improve laws and systems for collecting and reporting geology-related materials, making thematic maps, and maintaining and managing geological information we need to establish national strategies and build an integrated system for interoperability of databases and systems. Accordingly, we will guideline on future direction of strategies for the national integration of geological information management system.

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Educational Implications for Pre-Service Science Teacher Training through the Comparative Analysis between 'Integrated Science' based on the 2015 Revised Science Curriculum and Educational Contents presented in the Pre-Service Science Teachers' Textbooks of the College of Education (2015 개정 과학과 교육과정 '통합과학'과 사범대학 예비 과학 교사 교육 내용의 분석을 통한 예비 과학 교사 교육에 대한 시사점)

  • Kim, Nam Hui;Shim, Kew-Cheol
    • Journal of The Korean Association For Science Education
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    • v.35 no.6
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    • pp.1039-1048
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    • 2015
  • The purpose of this study is to examine implications of pre-service science teacher training by analyzing science field integration and connection between learning content presented in 'Integrated Science' for high school students based on the 2015 revised science curriculum, and in pre-service science learning materials (textbooks) of the college of education. For this study, the 2015 revised 'Integrated Science' curriculum and 11 types of pre-service science teachers' learning materials related to physics, chemistry, biological science, and earth science were selected. The results were as follows. Most of the learning content presented in the 2015 revised 'Integrated Science' curriculum had integrated two or more science fields. Also, almost all learning content presented in the 2015 revised 'Integrated Science' curriculum were included in pre-service science teachers' education content, with educational content for chemistry introduced at the highest rate. The textbooks for pre-service science teachers had the most learning contents of 'Energy and Environment' domain of 'Integrated Science' for high school students. Accordingly, these results suggest that 'integrated science materials' should be developed for proper the curriculum implementation. Also, training courses for science teachers responsible for 'Integrated Science' are required. Furthermore, a revised curriculum for the college of education and a method to link with certification examinations for secondary school teachers are needed.

Towards Integrated Pest Management of Rice in Korea

  • Lee, Seung-Chan
    • Korean journal of applied entomology
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    • v.31 no.3
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    • pp.205-240
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    • 1992
  • In reality, it is a green revolution of the entire agricultural matrix in Korea that integrated pest control plays an important role in the possible breakthrough in rice self-sufficiency. In paddy agroecosystem as man-modified environment, rice is newly established every year by transplantation under diverse water regimes which affect a microclimate. Standing water benefits rice by regulating the microclimate, but it favors the multiplication of certain pets through the amelioration of the microclimate. Further, the introduction of high yielding varieties with the changing of cultural practices results in changing occurrence pattern of certain pests. In general, japonica type varieties lack genes resistant to most of the important pests and insect-borne virus diseases, whereas indica type possesses more genes conferring varietal resistance. Thus, this differences among indica type, form the background of different approaches to pest management. The changes in rice cultivation such as double cropping, growing high-yielding varieties requiring heavy fertilization, earlier transplanting, intensvie-spacing transplanting, and intensive pesticide use as a consequence of the adoption of improves rice production technology, have intensified the pest problems rather than reduced them. The cultivation of resistant varieties are highly effective to the pest, their long term stability is threathened because of the development of new biotypes which can detroy these varieties. So far, three biotypes of N. lugens are reported in Korea. Since each resistant variety is expected to maintain several years the sequential release of another new variety with a different gene at intervals is practised as a gene rotation program. Another approach, breeding multilines that have more than two genes for resistance in a variety are successfully demonstrated. The average annual rice losses during the last 15 years of 1977-’91 are 9.3% due to insect pests without chemical control undertaken, wehreas there is a average 2.4% despite farmers’insecticide application at the same period. In other words, the average annual losses are prvented by 6.9% when chemical control is properly employed. However, the continuous use of a same group of insecticides is followed by the development of pest resistance. Resistant development of C. suppressalis, L. striatellus and N. cincticeps is observed to organophosphorous insecticides by the mid-1960s, and to carbamates by the early 1970s in various parts of the country. Thus, it is apparent that a scheduled chemical control for rice production systems becomes uneconomical and that a reduction in energy input without impairing the rice yield, is necessarily improved through the implementation of integrated pest management systems. Nationwide pest forecasting system conducted by the government organization is a unique network of investigation for purpose of making pest control timely in terms of economic thresholds. A wise plant protection is expected to establish pest management systems in appropriate integration of resistant varieties, biological agents, cultural practices and other measures in harmony with minimizing use of chemical applications as a last weapon relying on economic thresholds.

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Pink Pigmented Facultative Methylotrophic Bacteria(PPFMs): Introduction to Current Concepts (분홍색 색소를 형성하는 methylotrophic acteria(PPFMs): 최근 경향소개)

  • Munusamy, Madhaiyan;Sa, Tongmin;Kim, Jai-Joung
    • Korean Journal of Soil Science and Fertilizer
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    • v.37 no.4
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    • pp.266-287
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    • 2004
  • The non infecting, plant associated bacteria have attracted increased attention for stimulating plant growth and as environmental friendly plant protecting agents. Pink-pigmented facultatively methylotrophic bacteria (PPFMs), classified as Methylobacterium spp., are persistent colonizers of plant leaf surfaces. As the leaves of most or all plants harbor PPFMs that utilize leaf methanol as their sole source of carbon and energy, which is a specific attribute of the genus Methylobacterium. Although they are not well known, these bacteria are co-evolved, interacting partners in plant metabolism. This claim is supported, for example, by the following observations: (1) PPFMs are seed-transmitted, (2) PPFMs are frequently found in putatively axenic cell cultures, (3) Low numbers of seed-borne PPFMs correlate with low germinability, (4) Plants with reduced numbers of PPFM show elevated shoot/root ratios, (5) Foliar application of PPFMs to soybean during pod fill enhances seed set and yield, (6) Liverwort tissue in culture requires PPFM-produced vitamin B12 for growth, (7) treated plants to suppress or decrease disease incidence of sheath blight caused by Rhizoctonia solani in rice, and (8) the PPFM inoculation induced number of stomata, chlorophyll concentration and malic acid content, they led to increased photosynthetic activity. Methylobacterium spp. are bacterial symbionts of plants, shown previously to participate in plant metabolism by consuming plant waste products and producing metabolites useful to the plant. There are reports that inform about the beneficial interactions between this group of bacteria and plants. Screening of such kind of bacteria having immense plant growth promoting activities like nitrogen fixation, phytohormone production, alleviating water stress to the plants can be successfully isolated and characterized and integration of such kind of organism in crop production will lead to increased productivity.

BIPV System Design to Enhance Electric Power Generation by Building up a Demonstration Mock-up and Analyzing Statistical Data (실증 목업의 구축 및 데이터의 통계적 분석을 통한 건물일체형 태양광 발전시스템의 전력발전 향상 설계)

  • Lee, Seung-Joon;Lee, Jae-Chon
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.19 no.6
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    • pp.587-599
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    • 2018
  • In building-integrated photovoltaic (BIPV) systems, power generation functions are integrated into building functions by installing solar modules in combination with building materials. While this integration appears to be attractive, a design method is needed to achieve maximum power generation. Previously, the influence of the design elements on power generation was analyzed by computer simulations and demonstration tools. On the other hand, problems remain due to the inaccuracy of power generation analysis and relationship analysis, and limited demonstration. To solve this problem, this paper proposed the use of an extended demonstration mock-up. The mock-up was designed and constructed by implementing the design elements of the module types, installation angles, and direction. The actual operation data for one year were analyzed to evaluate the effects of the design elements on power generation. These results can be used to determine the feasibility of future BIPV systems and the optimal selection of system design elements.

Long-term clinical and experimental/surface analytical studies of carbon/carbon maxillofacial implants

  • Szabo, Gyorgy;Barabas, Jozsef;Bogdan, Sandor;Nemeth, Zsolt;Sebok, Bela;Kiss, Gabor
    • Maxillofacial Plastic and Reconstructive Surgery
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    • v.37
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    • pp.34.1-34.14
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    • 2015
  • Background: Over the past 30-40 years, various carbon implant materials have become more interesting, because they are well accepted by the biological environment. The traditional carbon-based polymers give rise to many complications. The polymer complication may be eliminated through carbon fibres bound by pyrocarbon (carbon/carbon). The aim of this study is to present the long-term clinical results of carbon/carbon implants, and the results of the scanning electron microscope and energy dispersive spectrometer investigation of an implant retrieved from the human body after 8 years. Methods: Mandibular reconstruction (8-10 years ago) was performed with pure (99.99 %) carbon implants in 16 patients (10 malignant tumours, 4 large cystic lesions and 2 augmentative processes). The long-term effect of the human body on the carbon/carbon implant was investigated by comparing the structure, the surface morphology and the composition of an implant retrieved after 8 years to a sterilized, but not implanted one. Results: Of the 16 patients, the implants had to be removed earlier in 5 patients because of the defect that arose on the oral mucosa above the carbon plates. During the long-term follow-up, plate fracture, loosening of the screws, infection or inflammations around the carbon/carbon implants were not observed. The thickness of the carbon fibres constituting the implants did not change during the 8-year period, the surface of the implant retrieved was covered with a thin surface layer not present on the unimplanted implant. The composition of this layer is identical to the composition of the underlying carbon fibres. Residual soft tissue penetrating the bulk material between the carbon fibre bunches was found on the retrieved implant indicating the importance of the surface morphology in tissue growth and adhering implants. Conclusions: The surface morphology and the structure were not changed after 8 years. The two main components of the implant retrieved from the human body are still carbon and oxygen, but the amount of oxygen is 3-4 times higher than on the surface of the reference implant, which can be attributed to the oxidative effect of the human body, consequently in the integration and biocompatibility of the implant. The clinical conclusion is that if the soft part cover is appropriate, the carbon implants are cosmetically and functionally more suitable than titanium plates.