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복잡 지형 내 대기 확산 해석을 위한 동적 경계 조건 자동 조정
No full textThe computational fluid dynamics (CFD) in the area of agricultural researches has been widely embraced as a very effective tool. The application of CFD has spread to various fields due to the accuracy and realism of CFD simulations. Amongst various problems in agriculture, this study dealt with the atmospheric environmental problem, especially transport and dispersion of livestock odor in the atmosphere, which was increasing in most countries. Because many limitations in understanding and predicting the odor dispersion have been endured in field experiments, this study was started to predict the quantitative and qualitative odor dispersions over complex terrain under various weather conditions.
In chapter 4, as the first step of the study, various phenomena and influence factors of odor dispersion from livestock farms were investigated in two target areas through field experiments. The odor concentration was generally decreased according to the leeward distance from the farm, however, several excessive or deficient values were found due to topographical effect, unstable weather conditions, atmospheric stability, etc. When the wind conditions were stable, the atmospheric stability was the most influential factor in odor dispersion. All measured data, including odor distributions and meteorological data, were utilized to build CFD model and to verify the accuracy of simulation results.
In chapter 5, the wind tunnel experiments were conducted to determine the primary design conditions in advance of a CFD modeling. Through heat dispersion test under various turbulent inflows, the large eddy simulation (LES) model was appropriate to dispersion modeling under all turbulent flows. The grid size of 5 m was determined for modeling of wide terrain and the size up to 10 m were also supposed to be allowed in some cases. The time step size of 1 s or slightly longer proven to be appropriate considering computational cost.
In chapter 6, some methodologies for terrain modeling to simplify the creation of complex topography for CFD analysis were presented. The terrain modeling method was to make triangulated irregular network (TIN) faces on the contour lines, then drape the solid surfaces over the TIN structures. This method which used various graphical tools resulted in high resolution and shorter computational time. The upper boundary was made flat to improve numerical convergence, and raised up to 2,500 m height to alleviate the effects of high mountains.
In chapter 7, CFD model was developed for the atmospheric dispersion modeling of livestock odor. To model the atmospheric conditions, such as atmospheric stability, wind shear and insolation, modules for atmospheric dispersion model (MADM) was developed. The MADM automatically controlled the dynamic boundary conditions of CFD model to simulate changing wind environments as realistically as possible. The livestock odor was modeled as odorous gas parcel mixture (OGPM). The use of CFD simulation with the LES and MADM produced the accurate wind fields, which was main mechanism of dispersion phenomenon, over complex terrain, and the wind environment and odor distributions computed by CFD model were well agreed with the field measurements. From odor predictions under various weather conditions, the most critical conditions were the westerly wind with neutral or stable atmospheric stability for Cheongyang area, and the north-westerly wind with stable stability for Yesan area.
In chapter 8, utilizing the CFD modeling and simulation approaches, the environmental impact of livestock odor was evaluated and quantified, and the performance of windbreaks to reduce the odor dispersion was assessed. CFD has proved to be an effective method to take preventive measures against livestock odor dispersion. Consequently, the use of CFD would help the farm holders and government employees to make quick decisions on probable odor problems and its solution.전산유체역학은 다양한 농업 연구들에서 매우 효과적인 접근법으로 알려져 있으며, 특히 높은 정확도로 현실적인 구현이 가능하기 때문에 다양한 분야에서 응용되고 있다. 이 중 본 연구에서는 대기 환경 내 오염 물질 이동 문제에 접근하고자 하였으며, 그 중에서도 최근 많은 국가들에서 문제시 되고 있는 축산 악취의 확산 문제를 다루고자 하였다. 그 동안 현장 실험에 의존한 연구들에서 이러한 악취의 확산 문제를 다뤄왔으나 대부분 많은 한계에 부딪혀 왔으며, 이러한 한계를 극복하기 위하여 본 연구에서는 전산유체역학 시뮬레이션을 활용하여 다양한 기상 환경 조건과 복잡한 지형 조건에서 확산되는 악취의 분포를 정성적 및 정량적으로 예측하고자 하였다.
제 4장은 본 연구의 첫 단계로서, 축산 농가가 위치한 두 지역을 선정하여 현장실험을 수행하고, 이로부터 악취의 확산을 측정하고 다양한 영향 요인들을 분석하였다. 그 결과 악취의 농도는 전반적으로 축산 농장으로부터 풍하측으로 갈수록 감소하는 경향을 보였으나, 일부 측정 지점에서는 지형적인 요인, 불안정한 기상 요소, 대기안정도 등의 영향에 의하여 악취 농도가 지나치게 높거나 낮게 나타나기도 하였다. 이러한 영향 요인들 중, 풍향과 풍속이 일정할 경우, 대기 안정도가 악취의 확산 현상에 가장 큰 영향을 미치는 것으로 나타났다. 또한 본 현장실험을 통하여 측정된 악취 분포 및 기상 자료들은 모두 전산유체역학 모델을 만들고 그 정확도를 검증하는데 사용되었다.
제 5 장에서는 풍동실험을 통하여 전산유체역학 시뮬레이션의 주요 설계 인자들을 결정하였다. 다양한 난류 강도를 가진 유입기류에 대하여 열 확산 실험을 수행하고 확산 양상을 시뮬레이션과 비교한 결과, LES 모델을 사용할 경우 모든 난류 정도에 대하여 확산 현상을 가장 잘 모의하는 것으로 나타났다. 또한 격자의 크기는 5m 정도에서 경우에 따라 10m 정도로 사용하고, 연산 시간간격은 1초나 10초 정도를 사용할 경우 경제적으로 적절한 계산 결과를 얻을 수 있는 것으로 나타났다.
제 6 장에서는 복잡한 지형 형상을 전산유체역학 시뮬레이션에 사용하기 위한 계산 영역으로 설계하는 방법을 다루었다. 본 연구에서 제안하는 방법은 먼저 등고선 형태의 지형 정보를 불규칙 삼각망 (TIN) 면으로 변환하고, 이 위에 솔리드 형태의 면을 덮어 씌워 지형과 동일한 형상의 솔리드 면을 만드는 방법이다. 비록 몇몇 그래픽 프로그램들이 필요하지만 비교적 짧은 시간에 고해상도의 지형 모델을 설계할 수 있다. 또한 계산 영역의 윗면은 수렴성을 높이기 위하여 편평하게 만들었으며, 계산 영역 내 높은 산에서 단면 축소효과가 나타나지 않도록 약 2500m 정도의 높이로 여유있게 설계하였다.
제 7 장에서는 대기 중 축산 악취의 확산을 모의하기 위한 전산유체역학 모델을 완성하였다. 대기 안정도, 바람시어, 일사 등의 기상 효과를 구현하기 위하여 MADM 모듈을 만들었으며, MADM은 CFD 모델의 동적인 경계 조건들을 자동적으로 조정하여 현실과 유사하게 변화하는 풍환경을 모의하도록 하였다. 축산 악취는 OGPM으로 모의되었다. 바람장과 악취 확산 분포의 시뮬레이션 계산 결과를 현장 실험 결과와 비교한 결과 매우 일치하는 결과를 얻을 수 있었으며, 이로부터 MADM 과 LES 모델을 이용한 시뮬레이션 모델이 복잡 지형 내 바람장과 악취의 확산을 정확히 예측하는 것으로 판단할 수 있었다. 검증된 모델을 활용하여 다양한 기상 조건에서 악취의 확산을 모의하였으며, 그 결과 악취 문제에 가장 취약한 환경 조건은 청양 지역의 경우 서풍계열이 불고 대기 안정도가 중립 내지 안정일 경우로 나타났다. 또한 예산 지역의 경우는 북서풍 계열이 불고 대기 안정도가 안정일 경우로 나타났다.
제 8 장에서는 전산유체역학 시뮬레이션의 활용 방안을 검토하였다. 본 연구의 시뮬레이션 연구를 적용하여 두 실험 지역에 대한 축산 악취의 환경 영향을 평가하고 정량화하였다. 또한 방풍림을 설치할 시 예상되는 악취 확산의 저감을 모의하고 평가하였다. 이러한 결과들로부터 전산유체역학 시뮬레이션은 축산 악취에 대한 대책을 수립하는데 매우 효과적인 접근법을 제시할 수 있으며 또한 악취 문제들에 대한 다양한 정책결정에 능동적으로 활용될 수 있을 것으로 판단된다.Docto
Going Beyond Counting First Authors in Author Co-citation Analysis
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counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
Author Under Sail The Imagination of Jack London, 1893-1902
No full textIn Author Under Sail, Jay Williams offers the first complete literary biography of Jack London as a professional writer engaged in the labor of writing. It examines the authorial imagination in London's work, the use of imagination in both his fiction and nonfiction, and the ways he defined imagination in the creative process in his business dealings with his publishers, editors, and agents. In this first volume of a two-volume biography, Williams traverses the years 1893 to 1902, from London's "Story of a Typhoon" to The People of the Abyss. The Jack London who emerges in the pages of Author Under Sail is a writer whose partnership with publishers, most notably his productive alliance with George Brett of Macmillan, was one of the most formative in American literary history. London pioneered many author models during the heyday of realism and naturalism, blurring the boundaries of these popular genres by focusing on absorption and theatricality and the representation of the seen and unseen. London created an impassioned, sincere, and extremely personal realism unlike that of other American writers of the time. Author Under Sail is a literary tour de force that reveals the full range of London as writer, creative citizen, and entrepreneur at the same time it sheds light on the maverick side of machine-age literature.Intro -- Title Page -- Copyright Page -- Dedication -- Contents -- Acknowledgments -- Introduction -- 1. Spirit Truth -- 2. From Absorption to Theatricality and Back Again -- 3. "I Will Build a New Present" -- 4. Sons as Authors -- 5. Fathers as Publishers -- 6. The Daughter as Author -- 7. Lovers as Authors -- 8. At Sea with the Family -- 9. Yellow News, Yellow Stories -- 10. The Return Home -- Notes -- Bibliography -- Index -- About Jay WilliamsIn Author Under Sail, Jay Williams offers the first complete literary biography of Jack London as a professional writer engaged in the labor of writing. It examines the authorial imagination in London's work, the use of imagination in both his fiction and nonfiction, and the ways he defined imagination in the creative process in his business dealings with his publishers, editors, and agents. In this first volume of a two-volume biography, Williams traverses the years 1893 to 1902, from London's "Story of a Typhoon" to The People of the Abyss. The Jack London who emerges in the pages of Author Under Sail is a writer whose partnership with publishers, most notably his productive alliance with George Brett of Macmillan, was one of the most formative in American literary history. London pioneered many author models during the heyday of realism and naturalism, blurring the boundaries of these popular genres by focusing on absorption and theatricality and the representation of the seen and unseen. London created an impassioned, sincere, and extremely personal realism unlike that of other American writers of the time. Author Under Sail is a literary tour de force that reveals the full range of London as writer, creative citizen, and entrepreneur at the same time it sheds light on the maverick side of machine-age literature.Description based on publisher supplied metadata and other sources.Electronic reproduction. Ann Arbor, Michigan : ProQuest Ebook Central, YYYY. Available via World Wide Web. Access may be limited to ProQuest Ebook Central affiliated libraries
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