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Behavioral Studies of Scuttle Flies (Diptera: Phoridae) and Its Forensic Importance in Taipei Area
No full text蚤蠅科包含200多個屬與3000多種，是雙翅目中的一個具高生態多樣性的大型類群。它們包含寄生性與捕食性的物種；其他廣泛取食的種類在人類的生活周遭成為重要的居家害蟲，有些食腐性的種類亦出現在法律案件的紀錄。暴露的屍體提供了野生動物豐富卻短暫的資源，麗蠅與肉蠅是其中最常被利用來判斷死後間隔時間的昆蟲，但是位於地下屍體的腐爛速度常遠低於暴露於空氣中，容易造成死後間隔時間的誤判，因此找出法醫昆蟲中可應用於協助地下屍體鑑識的昆蟲是有其必要的。在麗蠅無法侵入的土壤深層中，蚤蠅時常隨著地下屍體的發掘而出現，但蚤蠅通常會被誤認為是露天暴露屍體腐爛後期才大量產生的昆蟲，而其中Megaselia scalaris (Loew) 在自然與都市環境中，均是常見的世界性分布的腐食性種類，有高於麗蠅的入侵能力與分布範圍，在法醫研究方面具有普遍應用之可能性。本研究之目的為調查台北公館地區可能出現的法醫重要性蚤蠅的種類，得到6種蚤蠅，其中 Dohrniphora cornuta (Bigot) 與Diplonevra peregrine (Wiedemann) 為地下屍體上的優勢物種。並嘗試證明蚤蠅M. scalaris是否可穿過土壤，並在地下的目標上產卵；在野外以大白鼠埋入地下模擬可能在地下出現的屍體，確定蚤蠅在地下屍體法醫昆蟲方面應用的可能性。本實驗設計以自製的壓克力盒裝入培養土，下方放置豬肝吸引蚤蠅鑽入土壤產卵，在低深度的土壤中初步證明蚤蠅穿土產卵的可能性，但是在較深與顆粒細密的土壤設置時，蚤蠅入侵成功率即降低；於實驗室中麗蠅科紅顏金蠅Chrysomya rufifacies 無法在土壤隔絕下產卵利用地下的屍體； M. scalaris 在本實驗中的結果顯示不適合用於短期地底屍體的法醫研究。我們相信了解Dohrniphora cornuta在短時間到達地底的能力與結合其發育時間的研究後，將可幫助預測屍體掩埋在淺層土壤中一星期到一個月的PMI。Phoridae is a large family of Diptera with highly biological diversity. There are about 200 genera and more than 3,000 species were identified in the world. Phorids are worthy to study because the larvae of most species are parasitoids or specialist predators. In other species, they also feed on dung, carrions, fungus, or plants, and some of them were recorded in the forensic cases. The majority of forensic cases that involve examination of insects found on a corpse are mainly concerning for the blow flies (Calliphoridae) and flesh flies (Sarcophagidae). People collect these data for estimating the earliest oviposition dates（EODs）and know how long the dead body was exposed there. The phorid flies may be found in many cases because their small bodies are able to enter the smallest opening, even several meter deepth in the soil. In this study, we collected 6 phorid species of possible forensic importance and captured maggots by using subterranean rat corpses which were set in different depth. Below the ground, 2 phorid species, Dohrniphora cornuta (Bigot) and Diplonevra peregrine (Wiedemann), were significantly more than other species. Magaselia scalaris (Loew) and blowflies were blocked by the soil. Abilities of flies to penetrate the ground under different sizes of soil granules and different soil depth were tested. Diplonevra cornuta was proved to have better ability to penetrate the soil than the other 2 phorid fly species. The penetrating ability of tested phorid flies is worse than previously recorded in other field studies. Finally, we believe it is useful to build a model of D. cornuta for covering the unexpected situation of decaying remains and estimating the postmortem interval (PMI) of the corpse buried in a shallow grave in a week to a month.致謝i文摘要ii文摘要iii錄iv次vi次viii、緒言1、往昔研究3、法醫昆蟲學3、蚤蠅科分類地位與生物學概論7、蚤蠅科在法醫昆蟲學的應用可能性10amp;#21441;、材料與方法16、試驗昆蟲之採集與飼養16、實驗設計16一）台北地區露天嗜屍性蚤蠅調查17二）台北地區地下嗜屍性蚤蠅調查18三）以大白鼠屍體埋於地下誘集鑽地蠅類之調查18四）蚤蠅科Megaselia scalaris下鑽能力實驗19五）麗蠅科紅顏金蠅Chrysomya rufifacies下鑽能力實驗21六）蚤蠅科Dohrniphora cornuta 下鑽能力實驗22七）蚤蠅科Diplonevra peregrina下鑽能力實驗22、實驗結果23、台北地區露天嗜屍性蚤蠅調查23、台北地區地下嗜屍性蚤蠅調查27、以大白鼠屍體埋於地下誘集鑽地蠅類之調查28、蚤蠅科Megaselia scalaris下鑽能力實驗32、麗蠅科紅顏金蠅Chrysomya rufifacies 下鑽能力實驗33、蚤蠅科Dohrniphora cornuta下鑽能力實驗33、蚤蠅科D. peregrina下鑽能力實驗34八、比較三種蚤蠅在不同深度的鑽土能力35、比較三種蚤蠅在不同培養土顆粒大小的鑽土能力36、討論38、結論43、參考文獻4
Development of a Snake Robot with Flexible Connectors and its Optimal Velocity Planning
No full text本研究發展一套以彈性體為連結之機器蛇，並在路徑、機構與動力限制下發展一套最佳化速度規劃模式。整條機器蛇包含五個模組，模組間以彈性體為連結，每個模組均由兩顆步進馬達所驅動，並由模組上之微控制器以差速方式控制其方向與速度。以彈性體連結可使機器蛇的行動蜿蜒柔軟，更為逼真似蛇。綜合考量徑向伸縮及側向彎曲時之彈性恢復力及力矩對機器蛇行進時所造成之影響，在路徑、機構與動力限制下本研究提出最佳速度規劃方法，可使機器蛇在無失步、無滑動的情形下，於最短時間內循規劃之路徑抵達目的地。In this research, a snake-like robot with flexible connectors is developed, and an optimal velocity planning approach is investigated under the constraints of path, kinematics and dynamics of the robot. The snake-like robot includes five modules which are connected by flexible connectors; each module is driven by two stepping motors and is controlled in differential way for its direction and speed by micro-controllers. Flexible connection makes the motion of the robot smoother and more snake-like. However, the elastic restoring force and torque due to longitudinal extension (or compression) and lateral bending of springs may affect the behavior of the snake-like robot during moving. The snake-like robot will be out of control unless proper planning. The snake-like robot is capable of following the planned path and arriving at the destination in minimum time without sliding or losing steps, if the optimal velocity planned by the study is applied.摘要 i
Abstract ii
目錄 iii
表目錄 vi
圖目錄 vii
符號說明 xii
第一章 前言 1
第二章 文獻探討 4
2.1 蛇的身體構造與運動模式 4
2.1.1 側向波動式 (Lateral undulation) 4
2.1.2 手風琴式 (Concertina) 6
2.1.3 側向捲曲式 (Side-winding) 6
2.1.4 直線式 (Rectilinear) 8
2.1.5 滑動推進式 (Slide-pushing) 8
2.2 機器蛇的機構設計 9
2.2.1 ACM 系列 10
2.2.2 蒼龍Souryu I, II 16
2.2.3 GMD系列 18
2.2.4 MAKRO 20
2.2.5 Mechanical Snake 22
2.2.6 Snakebot 24
2.2.7 Shape Shifter 25
2.3 大撓度彎曲之分析 27
2.3.1 Euler-Bernoulli Beam之應用 28
第三章 材料及方法 32
3.1 機器蛇的機構設計與製作 32
3.1.1零件材料選擇 34
3.1.1.1 外殼與輪子之材質 35
3.1.1.2 齒輪組 35
3.1.1.3 步進馬達 36
3.1.1.4 橡膠輪胎 43
3.1.2 控制電路設計與製作 43
3.2 單體受力分析 45
3.2.1 以NURBS曲線模擬彈簧外形 47
3.2.2 相鄰兩單體受力與力矩分析 52
3.2.2.1側向受力 52
3.2.2.2 徑向受力及力矩 55
3.2.2.3 特殊情形分析 60
3.3 機器蛇最佳速度之規劃 63
3.3.1 輪子角速度與規劃路徑之關係 64
3.3.2 最佳速度之規劃 65
3.3.3 加減速階段 70
第四章 結果與討論 74
4.1 模型驗證 74
4.1.1 直線模式 74
4.1.1.1 無滑動及無失步之情形 76
4.1.1.2 無失步但有滑動之情形 79
4.1.1.3 有失步但無滑動之情形 81
4.1.1.4 三種直線模式之比較 83
4.1.2 曲線模式 86
4.1.2.1 彈簧無伸縮，最高行進速度與迴轉半徑的關係 87
4.1.2.2 彈簧伸縮對最高行進速度的影響 95
4.2 單體測試 98
4.2.1 單體速度測試 99
4.2.2 基本運動模式測試 102
4.3 機器蛇運動模式測試 103
第五章 結論與建議 107
參考文獻 109
附錄一 11
Experimental studies on the growth, characterization and topological properties Bi2Se3 thin film
No full text拓墣絕緣體為近年來發現的新穎材料，其有著邊緣或表面能導電的特性與內部絕緣的特性。近年來主要成長硒化鉍（Bi2Se3）薄膜是由分子束磊晶（molecular beam epitaxy , MBE）的方式，然而此方式花費成本太高，理想的是有更簡單且經濟的方式製作樣品。 在此篇論文中，我們使用物理氣化沈積（physical vapor deposition, PVD）方式來製備硒化鉍薄膜成長在藍寶石基板（Al2O3）上，用此方式我們能在藍寶石基板長出1公分 1公分大面積的薄膜，此方式能將薄膜製備得更簡單且花費更低。物理氣化沈積方法是將硒化鉍粉末和藍寶石基板放入石英管中且用機械幫浦將石英館內壓力降低，我們將硒化鉍的粉末至於高溫爐中央，而藍寶石基板置於距離硒化鉍粉末15公分的下游處，我們使用500 或530 為硒化鉍氣化的溫度，沈積區基板溫度控制在300 或350 ，在成長過程中，環境壓力控制在 5X10^(-3)torr。 我們利用原子力顯微鏡（atomic force microscopy, AFM）來量測膜厚，結果顯示在不同的溫度與時間參數下，膜厚從8到60奈米。我們用X光繞射分析（X-ray diffraction, XRD）分析晶格結構，結果顯示我們成長的薄膜有很好的晶格結構，在Phi角掃描的結果顯示，我們的薄膜有六重對稱，其代表薄膜成長方式與外延模式是區域匹配的（domain matching epitaxy mode）；由X光能譜分析儀（energy-dispersive X-ray spectroscopy, EDS）分析薄膜成份，結果顯示鉍與硒的比例很接近2比3；由X射線光電子能譜儀（electron spectroscopy for chemical analysis, ESCA）分析硒與鉍的鍵結能量；由穿透式電子顯微鏡（Transmission Electron Microscopy, TEM）觀測薄膜排列結構，結果顯示我們成長的薄膜為層狀結構且每一五層結構的厚度為0.94奈米。 我們使用厚度為30奈米的薄膜製作成Hall bar的裝置來量測電性，量測結果顯示，在溫度從2 K到300 K間，載子濃度（carrier concentration）介於1.07X10^(19)/cm^3 與 1.09X10^(19)/cm^3之間，電阻率隨溫度的量測結果顯示，在溫度為4.5 K時發生金屬性與絕緣體性的轉換，電子遷移率（mobility）在溫度為2 K時為940，此量值高於脈衝雷射蒸鍍系統（Pulsed laser deposition, PLD）製備的薄膜18倍。磁阻量測顯示，弱反局部化（Weak anti-localization）效應出現在低磁場下，此結果顯示我們製備的薄膜有拓墣絕緣體的性質存在，用Hikami-Larkin-Nagaoka (HLN) 式子分析結果顯示，我們的薄膜有一個表面通道在導電且去相位長（dephasing length）為640奈米。Topological insulators are a new kind of innovative materials that have an insulating behavior in the bulk but a conducting behavior at the surface. Up to date, most of the high quality bismuth selenide (Bi2Se3) thin films were grown by using molecular beam epitaxy (MBE). This method, however, is too expensive and it is desirable to have a simpler and more affordable way of making the samples. In this work, the physical vapor deposition (PVD) method was used to grow large area Bi2Se3 thin films with size of cm2, on sapphire (Al2O3) substrates. This method has the advantage that it is simple and inexpensive. For the PVD growth the source powder and the substrate were placed in a quartz tube that is put inside a furnace and a mechanical pump is connected to the quartz tube to reduce the pressure in the tube. During the growth, Bi2Se3 powder was placed at the center of furnace, Al2O3 substrate was placed 15 cm away from the source powder, the source temperature was kept at either 500 or 530 , the substrate temperature was kept at either 300 or 350 , and the environment pressure was fixed at 5X10^(-3)torr. Atomic force microscopy (AFM) measurements indicate that, depending on growth durations, the thickness of Bi2Se3 thin films varies from 8 nm to 60 nm, X-ray diffraction (XRD) indicate that the films were of good crystalline quality. The six-fold symmetry of the phi-scan indicates that the growth mode is domain matching epitaxy mode. The energy-dispersive X-ray spectroscopy (EDS) measurements confirmed that the ratio of Bi and Se were 2 to 3 and the electron spectroscopy for chemical analysis (ESCA) showed that the binding energies are that for Bi and Se. Transmission Electron Microscopy (TEM) measurements indicate that the film had a layer by layer structure and the thickness of each quintuple layer is 0.94 nm. For the electrical measurement, the film with thickness of 30 nm was made into a Hall pattern. The carrier concentration in this sample is found to be between 1.07X10^(19)/cm^3 and 1.09X10^(19)/cm^3 from T=2k to T=300K and metal insulator transition was found to occur at 4.5 K. The mobility of the sample is 940 cm2/Vs at 2 K, about 18 times larger than similar film grown by using pulsed laser deposition. Weak anti-localization (WAL) was found at low magnetic field in the magneto-resistivity measurement, showing that the sample has the property expected for a topological insulator. By fitting the data with the HLN formula we found that the surface conduction occur only in one surface of the sample and the dephasing length of the electron is 640 nm
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
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