1,720,975 research outputs found
The study on artificial hatching of blue crayfish ( Procambarus alleni )
No full text中文摘要 本實驗主要研究目的為利用良好的孵化設備、水體環境控制、適當的臭氧消毒濃度與頻率以達到提到佛羅里達藍螯蝦卵人工孵化率。觀賞性淡水螯蝦具有高經濟價值，繁殖上常常受限於孵化時間過長及容易遭受水黴菌感染而失敗，因此希望藉由人工孵化方式來改善。螯蝦受精卵來自自然繁殖抱卵母蝦，將卵取下後，分為不同的處理組，並置入不同設定的人工孵化環境，控制其卵的密度或是水槽的溫度，以及嘗試使用臭氧水當做消毒劑來殺死水中的水黴菌，期許提高最後孵化率與幼苗活存率。 20℃的處理組別幼苗的三個時期（Stage I→III）平均活存率顯著高於24℃及28℃二組。受精卵接受不同濃度臭氧浸泡處理並與甲醛控制組消毒做比較，實驗結果發現孵化活存率隨著臭氧濃度與處理時間的上升而降低（stage III 53.8→60.6％），四個臭氧處理組別與甲醛控制組間沒有顯著差異。臭氧0.3 ppm同時消毒孵化水體與受精卵及僅單獨對水體做消毒與未處理之控制組相比皆有顯著的提升效果。溫度與消毒結合探討下，24℃的組別使用甲醛與臭氧消毒的各期幼苗孵化活存率顯著高於控制組。比較自然孵化與人工孵化，以臭氧0.05ppm同時處理水體與卵30分鐘/天，人工孵化組別的孵化活存率顯著高於自然孵化的組別。 總結以上，溫度20℃、密度40(顆/管)條件下有最佳孵化率；在臭氧或甲醛的運用於水體與卵的消毒上，可有效的提升孵化率，且顯著高於自然孵化的組別；由實驗結果得知，水中臭氧濃度0.05ppm，每天消毒一次，即有效取代甲醛的使用。目錄次：錄----------------------------------------------------- I次與表次---------------------------------------------- II錄次------------------------------------------------- III文摘要-------------------------------------------------IV文摘要-------------------------------------------------V一章 前言----------------------------------------------1二章 文獻整理------------------------------------------3三章 材料方法-----------------------------------------25四章 結果---------------------------------------------30五章 討論---------------------------------------------37考文獻-------------------------------------------------5
Environmental Effects on Sound Propagation in Shallow Waters
No full text本文目的為比較ASIAEX南海實驗音傳損耗(Transmission Loss)的資料與數值模擬結果，並探討水文及底質特性對淺海聲音傳播的影響。文中主要探討在ASIAEX南海實驗中，J-15-3第二條拖曳路徑中(5月5日23：31到5月6日00：23之間) CW訊號在140Hz時的音傳損耗，並將其理論計算與實際資料相比，發現數值模擬可因水文(內波)及底質參數之輸入調整，而與資料結果相仿，因此探討水文及底質特性問題。底質算例結果顯示底層聲速越高其音傳損耗越小，由聲源頻率50∼300Hz的結果發現，聲源頻率越低底層有效深度越深，而聲源頻率增加其有效深度則減少。水文算例結果顯示由內波所產生的音傳擾動會更加紊亂，因而在實際水文環境中，找出內波切確位置及速度就極為重要。The comparison between the data of the transmission loss in the ASIAEX SCS experiment and the result of the numerical simulations is presented in this paper. In addition, we try to discuss the effect of water column and sediment property on the acoustic propagation in the ocean. In this paper, we mainly discuss the transmission loss of CW tones transmitted in 140 Hz during a segment of J-15-3 RUN2 which started at 05/05 23:31 and ended in 05/06 00:23. Furthermore, according to the comparison between theoretical calculations and practical data, we found the result of the numerical simulations would be similar to the practical data if the parameter of water column (internal wave) and sediments are corrected. Therefore, it is necessary to consider water column as well as sediment property further. The result of the calculation of the sediment shows the transmission loss would get lower as the sound speed gets higher and in 50-300Hz range, the effect depth of the sediment is an inverse proportion to the source frequency. The results of water column case show that due to internal waves, the fluctuation in sound propagation becomes severer. Therefore it is very important to find out the exact locations and speed of internal waves in the real ocean environment.致謝及感言 ……………………............I
中文摘要…………………………………………………II
Abstract…………………………………………………III
目錄………………………………………………………IV
圖表目錄…………………………………………………VI
第一章 緒論……………………………………………1
1.1 背景介紹…………………………………………1
1.2 研究動機與目的…………………………………1
1.3 文獻蒐集…………………………………………5
1.4 研究方法…………………………………………7
1.4.1 PE拋物線方程式…………………………7
1.4.2 Normal Modes……………………………10
1.4.3 MOS3DPEF……………………………………….14
1.5 論文架構………………………………………….16
第二章 ASIAEX J-15-3 RUN2實驗分析及數值模擬……17
2.1 ASIAEX J-15-3 實驗簡介………………………18
2.1.1 實驗配置及步驟………………………………19
2.1.2 實驗區域海洋環境簡介………………………21
2.2 實驗訊號處理……………………………………28
2.3 數值模擬…………………………………………31
2.3.1 海洋音響環境建立……………………………31
2.4 結果與討論……………………………………………35
2.4.1實驗數據及數值模擬結果比較………………..35
2.4.2相關問題延伸…………………………………..42
第三章 淺海環境中底質特性對音傳之影響……………44
3.1 淺海底質對聲學性質之影響…………………………45
3.2 Hamilton之地音模型建立………………………….47
3.3 底質特性對音傳損耗的影響…………………………56
3.4 底質特性對音傳模組之影響…………………………65
3.4.1 不同底質的有效深度…………………………66
3.4.2 底層計算深度結果……………………………71
第四章 淺海環境水文對音傳影響…………………………79
4.1 內波對音傳損耗之影響………………………………79
4.1.1不同位置之內波對音傳之影響………………82
4.2 內波對模組之音傳影響…..……………………88
第五章 結論及未來研究方向…………………………100
參考文獻…………………………………………………10
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
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
Get PDF“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
Get PDFWe 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
Get PDFWe 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
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