MTU值與網路效率的關係
中文摘要：\r 本研究旨在探討，在TCP/IP 協定之下，最大網路傳輸效率之MTU\r （Maximum Transmission Unit,最大傳輸單位）值。根據IEEE 所公\r 佈Ethernet 之標準，經實地模擬實驗，本研究之結論如下：（1）在\r 單純兩台電腦直接串接時，由於幾乎無任何干擾與封包的碰撞，可設\r 定之MTU 最大值以1500bytes 為最佳；（2）但在模擬真實的大型廣域\r 網路時，由於碰撞增加及雜訊增多，經模擬實驗顯示，MTU 值為\r 1500bytes 時無法在資料傳送、接收及重組時取得平衡，最佳之MTU\r 值落於500 到600bytes 之間，進一步研究顯示MTU 值設在500 到\r 600bytes 時可提升傳輸效率約50%。同時，本研究亦討論將此機制應\r 用於未來新網路標準之可行性及其必要性。Abstract：\r The main purpose of this research is to explore the best network\r transmission efficiency's Maximum Transmission Unit under TCP/IP\r protocol. According to the Ethernet's standard of IEEE and simulated\r experiments, the outcome of this research are :( 1) When connecting two\r computers serially, there is almost no interference and impact of packets,\r the best MTU that we can set up is 1500bytes ;( 2)When simulating the\r truly wide area network, interference and impact are rising. The result of\r this simulates experiment shows that when MTU is at 1500bytes, it's\r unable to keep balance when sending, receiving and re-composing. The\r best new MTU is between 500bytes and 600bytes. And when MTU is\r between 500bytes and 600bytes, the network transmission efficiency can\r be promoted about 50% higher. At the same time, the research is also\r discussing the feasibility and necessity of applying it to the standard of\r the future network.
狂舞飛圈-簡單飛機的飛行動力研究
本實驗主要是探究雙圈圈簡單飛機的飛行原理，歸納圈圈結構對飛行距離、升力的影響，以及氣流流經機體時發生的作用。研究結果如下：一、實際發射，歸納影響滑行距離的變因。1. 前後圈直徑比值約為0.8 時滑行距離為最大。2. 前後圈寬度比值越接近1 時，滑行距離越遠，但影響不大。3. 圈圈間隔在21cm 時，滑行距離最大。二、設置風洞，模擬飛機飛行，測量升力1. 圈圈寬度越大，升力越大。2. 升力最大值出現在圈圈仰角25 度左右，風速越快，升力越大。3. 鋁片仰角在20°時升力最大，升力與角度的關係式為 F = 5×10?7θ4 + 4×10?5θ3 ? 0.0083θ2 + 0.2615θ + 0.13744. 風速越快，升力越大，在仰角20°時升力與風速的關係大約為F = 0.4579V2 - 0.9231V +1.4772 。5. 鋁片面寬每增加1cm，升力也增加0.1513gw。前後長每增加1cm，升力即增加0.1263gw。三、設置蒸汽氣流，觀察簡單飛機的氣流場1. 蒸汽流通過圈圈時，會發生附壁現象，而且簡單飛機使氣流往下偏折，飛機得到升力。四、理論演繹︰1. 以康達效應的理論推算出升力，與實際測量得的升力約相等，驗證升力確實由康達理論造成。2. 墊高簡單飛機前圈，使得軸線提高，確實影響了飛行距離，墊高1cm 以內，飛行距離均增加了，以實際的改進證實升力確實是康達效應。This experiment mainly discusses the flying principle of the simple plane which is made up of a straw with two paper circles, one bigger than the other, stuck on both two ends of it. We first launched the simple plane actually and concluded the factors which influenced the sliding distance of the plane, including the distance between two circles, diameter and width of the two circles. Second, we set up a simple wind-tunnel and simulated the flight, in order to measure the strength of lift. Third, we set up the steam air flow and observed the change of the air current in the steam flow while flowing through the plane. The Phenomenon of Wall Enclosing happened and made the flows downward, and the plane gained the lift at the same time. Finally, we deduced that there are two sources of lift and Benoulli's law is not suitable for it. The Coanda Effect can be applied to figure out 54 percent of lift. And the current, blocked by the plane, also offers some lift. In order to prove that the Coanda Effect does effect, we padded the first circle to enlarge the angle of elevation of the axis of the two circles. It really affected the sliding distance of the plane. While the first circle is padded up within 1 cm, the sliding distance of the plane increases. Practical improvement proves that Coanda Effect accounts for the lift.
氣候變遷對台灣地區異常降水的影響
Drought and inundation are two unusual natural disasters in Taiwan. The two natural disasters\r have some relation of abnormal rainfall become more and more in Taiwan. So it let me think about\r can climate vicissitudes make the chance of abnormal rainfall become more?\r The study have researched the chance of abnormal rainfall by "rainfall duration" and "total\r rainfall". It collect the day by day total rainfall from 1960 to July 2002, collect locals are Taipei,\r Taichung, Kaohsiung and Hualien. Than enter the data into the computer, let computer calculation\r total rainfall, rainfall days, heavy rain days, pouring rain days and torrential rain days. Then\r analysis the tendency of long-term change.\r According to the analysis, the chance of abnormal rainfall happened become more in Taipei,\r Taichung, Kaohsiung and Hualien. The ratio of Hualien and Kaohsiung is the most obviously. It's\r also find that there temperature and total evaporate became higher, the total sunshine duration\r became lower. Then El Nino have some influence in abnormal rainfal. In El Nino year, total rainfall\r will become lower. When La Nina year, the total rainfall will become more in Taipei and Hualien.\r Then the long influence is clearly in Taipei.\r 乾旱與水災是台灣地區相當常見的二項天災，這二項災害的發生都與異常降水有直接的\r 關係。近年來台灣地區因異常降水造成的天然災害，似乎有逐年增加的趨勢。因此讓人聯想\r 到氣候變遷是否會導致異常降水頻率增加。\r 本研究主要由「降雨時數」與「降雨量」二方面探討異常降水發生頻率。先收集台北、\r 台中、高雄、花蓮四地自1960 年至2002 年七月三十一日之逐日雨量資料，將資料輸入電腦\r 後，統計各站歷年降雨量、降雨日數、大雨、豪雨、暴雨日數，並分析長期變化趨勢。\r 分析結果，台北、台中、高雄、花蓮四地異常降水發生機率，有增加的情形；其中以花\r 蓮及高雄變化的比例最高。再與其他各地氣象要素比較可發現，可能與氣溫及蒸發量數上升，\r 以及日照時數縮短有關。另外聖嬰現象也可能對異常降水有長期性的影響。一般而言聖嬰年\r 雨量減少，反聖嬰年台北、花蓮地區雨量反而會增加。而長期性的影響，以台北地區最顯著。
形?與形外
在這篇研究報告中,我用了三種觀點來推廣幾何中的反演變換,首先,把反演變換視為是一種圓內與圓外的一種1-1且onto的映射,第一種推廣,是將變換中心移到視圓心以外的圓內的地方,馬上我們得到一個結論「反演半徑會隨著動點而改變」,接著,我們實驗了一下反演變換用有的一些性質,保角性,保圓性,…等在這個變換視中是否依然存在;接著我們用第二種方法來推廣反演變換,我們將邊界的形狀由圓視改成別的形狀(如三角形,四邊形…等等),然後也試試看在這種變換之下是否還擁視有反演變換的一些性質;第三種推廣,則是在研究的過程中,我發現了一種新的幾視變換,承接第一種推廣,我們將原先為定點的變換中心改為動點,將原先的動點改為定點,做出來的一種新變換。In the study, a new geometric Inversive transformation through three points is discovered. Here is the main result：（1）The first, onto cycle of inside and outside can be proved under invasive transformation. It is changed moving the center from center of cycle, we can get a new ” Inversive radius can be changed by moving drop. (2) We hope to find the answer to this problem by experiment, it is exist with the inversive properties. (3) A new geometric transformation is discovered, a fixed drop can be changed moving drop, then the first moving drop shifted the fixed drop. This leads to a new construction if the new transformation.
滿足
之M點是否為重心之探索
滿足之M 點，我們稱之為Pi(i=1…n)的均值點。當n=3，M 恰為△P1P2P3 的重心 (G); n=4 時，M 亦為三角錐P1P2P3P4 的重心！因此不免引人遐思：滿足之M 點是否皆為其重心？
我們藉由電腦幾何作圖軟體GSP 協助觀察，掌握了圖形變化間之不變性，再配合向量解析及推理，得以發現均值點、多邊形的重心、以至多面體的重心、及平行多邊形的一般性作法。附帶又發現：任意相鄰三頂點即可決定一平行n 邊形。並進而證實：平行四邊形為四邊形M＝G 的充要條件。但當n≧5 時，平行n 邊形只是n 邊形M＝G 的充分非必要條件！一般而言，具有對稱中心O 的n 個點所構成的圖形必可使M 與G 重合於O 點上。
The point M satisfying is called “the mean point of Pi(i=1…n)”. As n=3, M is the center of gravity (G) of the △P1P2P3. If n=4, then M is also the center of gravity of the triangular pyramid P1P2P3P4. Therefore, I began to wonder if the following assumption stands: The point M that satisfies is always a center of gravity.
By using the computer software GSP (The Geometer’s Sketchpad) to observe figures. It is found that when a figure is changing there is still constancy. Furthermore, supported by the analysis based on vectors, general constructions can be established concerning the mean point, the center of gravity of polygon, the center of gravity of polyhedron, and the parallel polygon. Also, I find that any three neighboring vertexes decide a parallel polygon. And thus it is verified that the parallelogram is the sufficient and necessary condition for quadrilateral M=G. As n≧5, the parallel n-sides shape is the sufficient, not necessary condition, for n-sides shape M=G. In general, a central figure of n points having the center of symmetry O can make M and G meet on O.
蝴蝶眼斑的探討
在眾多的蝴蝶中有不少是具有眼斑。傳統上認為眼斑的功能是驚嚇天敵或欺騙天敵。有關眼斑本身結構的瞭解很少。我們利用臺灣及馬祖產的蝴蝶，分別記錄圖鑑上峽蝶、眼蝶及灰蝶合計 60 種以上，以及鳳蝶幼蟲七種的眼斑特性。記錄的眼斑特性包括數目、組成的色彩結構，以及記錄眼斑在翅的腹面或背面明顯。進一步測暈孔雀峽蝶、台灣波眼蝶、蘇鐵小灰蝶等三種蝴蝶的眼斑和翅面積。眼斑在腹面及背面都有，但以腹面明顯者佔多數，而眼斑數 l 一 7 個都有，在後翅者佔多數。眼斑慕本是由數個同心圓組成，分別為輪廓、眼白、虹彩及障孔。在峽蝶及眼蝶的結構都相當完整，輪廓為褐或深褐，眼白為黃色為主，虹彩都為黑色或深褐色，障孔為白色或淡藍色。在灰蝶的眼斑較不完整，大都輪廓不清晰，眼白的黃色或橙色部份比例高，但都缺少障孔。幼蟲有眼斑成蟲不一定有。鳳蝶的幼蟲（ 8 種）都為綠色，其眼斑輪廓黑色，眼白為白色及紅色但明顯比上述成蟲的眼斑之眼白部位要小，而黑色的虹彩都很大。幼蟲的障孔為白色的細線形，我們認為這和立體形狀的幼蟲及成蟲平面翅的差異所造成，在文中也討論到水棲蝶魚的眼斑和蝴蝶眼斑的差異。眼斑和翅面積的相關分析結果變異很大，在統計上正相關及負相關都有。眼斑數目的不定及和翅面積並沒有一定關係，我們討論到蝴蝶的眼斑在不同種類有些可能有求偶生殖上的功能。這方面值得科學家大量投入研究。Quite a few species of butterflies have colorful eyespots on their wings. The main functions of these eyespots were considered to startle or deceive predators by most scientific researchers. In fact, only limited literatures dealt with the basic structure and color patterns of butterfly eyespots. The purpose of this study is to study the basic structure and color patterns of these eyespots. We measured the surface area of eyespots v.s. wings from specimens. From the color plates of Taiwan and Matsu butterfly field guide, we recorded the eyespots either on ventral or dorsal side of wings, and the color patterns for more than 60 species. \r The number of eyespots on wings varies from I to 7 among individuals we checked. Majority of eyespots were found on ventral side of wings. The basic structure of eyespots were formed by I to 3 concentric circles, i.e., outboundary, cornea, iris and pupil . Pupil was not found in certain species. The color in cornea section is yellow and in iris is black or dark brown. The contrast in these two areas is quite prominent just as the contrast showed in warning coloration of after animals. The pupil is either white of light blue. Caterpillars with eyespots were found in Papilionidae, their adult stage were without this character. We checked 8 species of caterpillars, their basic structure of eyespots were similar to other butterflies, with cornea, iris and pupil. The cornea is either red or white color, and the iris is black in colors. The ratio(iris/cornea) is much higher in caterpillar than in butterfly. The pupil is a thin thread shape instead of a tiny spot like the one in butterfly wings. We discussed the difference of pupil between juveniles and adults from the aspect of dimension structure of a subject. In the paper we also discussed the difference of eyespots between butterfly and butterfly fish in the coral reef. Base on the no significant relationship between the surface area of eyespots and wings. We suspect that butterfly eyespots may have another function, such as intersexual selection between males and females beside startling and deceiving predators.\r
旋光性介質對電磁波影響的分析與討論
This experiment mainly aims at three kinds of solution - Dextrose, Saccharose, and Fructose. By changing its temperature, density, length of tube, as well as different wave length factor of polarized light, we observe the influence of the direction of polarization by those factors. The experimental result showed as follow. The Dextrose and the Saccharose can cause the polarized light with the rotary direction of clockwise, so both are ‘dextrorotatory’. The Fructose can cause the polarized light with the direction of counterclockwise, so it is the ‘laevorotatory’. For the Dextrose, when the\r temperature is lower than 20℃, the direction of polarization has changed observably, but doesn’t have any rule. When the temperature is higher than 20℃, the direction of polarization increase slowly. For those three kinds of solution, when\r density increased, the polarization increased observably. When the polarized light passed through the solution with longer path, the direction of polarization has more change. When the wave length of the polarized light changed, the direction of polarization has been changed observably. When the wave length of the polarized light is shorter, the direction of polarization change increased.本實驗主要針對葡萄糖、蔗糖、及果糖等三種旋光性溶液，改變其溫度、濃度、容器管長、以及不同波長的偏振光等因子，觀察這些因素對偏振方向所造成的影響。實驗結果顯示：葡萄糖與蔗糖會使得偏振光的偏振方向以順時針旋轉，屬右旋性之光學異構物；果糖會使得偏振光的偏振方向以逆時針旋轉，屬左旋性之光學異構物。若溶液為葡萄糖，當溫度低於20℃時，偏振光的偏振方向會有明顯的改變，但無規則可尋；當溫度大於20℃時，偏振方向旋轉角位移則以非常緩慢的方式增加。當此三種溶液之濃度增加時，偏振光的偏振方向有明顯遞增的現象。此外，當容器長度越長（即偏振光在介質中的行程越長）時，偏振方向的改變亦越明顯。當偏振光的波長改變時，偏振光的偏振方向有明顯的變化，且當偏振光的波長越短，偏振方向的改變越大，似乎與波長呈反比，但此結果與理論值（即旋光度與波長平方成反比）仍有一些差距。
直角三角形生成關係的研究與發展
k(2αβ ,α2 ? β2,α2 + β2 )是大家熟悉畢氏定理的通式解，且一般書籍的証明大都採用代數的手法證明。以國中生而言，上述的代數方對國中生來說不夠直接且較無推展的實用性。因此幾何觀點出發發展另一種思考方式，利用角平線的性質給予畢氏定理比例解另一種全新的詮釋，並賦予比例解中的參數α 、β 在幾何的意義。在推理的過程中，我們得到一個相當有用的對應關係：一個有理數對應到一個直角三角形、兩個有理數對應到海倫三角形，再將此對應關係運用到各種幾何圖形上面，即可證明出他們所對應的通式解。最後我的興趣鎖定在海倫三角形、完美海倫多邊形與超完美海倫多邊形上的做圖方法上，善用我們所發展的對應關係，上述的問題皆可迎刃而解。k(2αβ ,α2 ? β2,α2 + β2 ) is a popular formula in Pythagoras Theory, often proved in algebra approach among books. Nevertheless, in light of junior high students, the aforementioned algebra method is neither direct nor practical. Hence, a different thinking method is derived from geometry perspective, using the straight line concept to reinterpret Pythagoras Theory and define the geometric meanings of α andβ . In the process of logical development, a useful correlation emerges: a rational number correlates with a straight-angled triangle, and two rational numbers correlate with Heron Triangle. This correlation can be applied to all kinds of geometrical diagrams to prove the correlated homogenous solution. Ultimately, my interest lies in the diagram methods of Heron Triangle, Perfect Heron Polygon, and Super Perfect Heron Polygon in order to apply our developed correlations to solve the above mentioned problems.
表面粗糙結構對疏水性影響之應用與研究
本研究從大自然中之「蓮花效應」引發學習興趣與研究動機，在蒐集相關資訊與文獻後，發現疏水功能不只是防水，還關係著日常生活品質之許多材料特性，包括防水、撥水、防潮、防銹、防蝕、抗菌防污、自清潔…等。而影響固體表面疏水性之兩大特性，包括物理之表面粗糙度與化學之超低表面能，本研究針對物理之表面粗糙度與疏水性之關係做探討，以相同之化學特性來比較不同號數之工業用砂紙之疏水行為，並就廣泛被引用之兩種模擬表面粗糙度與疏水性關係之模式：Wenzel and Cassie model，比較現有文獻對兩種模式之特性，選擇Cassie model 來進一步實驗驗證，以量測之平均接觸角 Θ 推算Cassie model 之表面粗糙係數Φ 值，並簡化不同砂紙顆粒模型為相同粒徑之球狀，以簡化之方程式來求得水珠與砂紙顆粒之實際接觸面積與球心夾角 θ，以提供高中學校能在經費與設備之限制下，仍能有效應用與印證Cassie model，獲得砂紙顆粒直徑與球心夾角 θ 自然對數值之關係。並就疏水性之生活應用，建立接觸角與 Φ 之關係曲線，驗證實驗之方程式，與延續過去之科展成果，以實驗成果提出可行性應用之建議。The interest and motivation of the present work was introduced from “lotus effect” in nature. After we collected related literature and information, we found that the function of the so-called “superhydrophobicity” behaves not only water repellency, but also a variety of real-life applications, including anti-fog, anti-corrosion, anti-bacteria, anti-fouling, self-cleaning, and so on. Pervious studies have pointed out that two criteria affecting the performance of hydrophobic surfaces are physical (roughness) and chemistry (surface tension) properties. This study focused on influence of physically surface roughness on hydrohyphobicity. Based on an identical surface chemistry, we employed different types of industrial sandpapers to mimic the lotus leaf, and investigated the relationship between roughness and hydrophobicity by using two famous models: Wenzel and Cassie models. Comparing with their basic assumptions to our study, we applied Cassie model to confirm our experimental results, in where one Cassie parameter (?) was proposed to simplify the Cassie equation. This superhydrophobic behavior can be well predicted by the Cassie model. This study continues previous achievement and offers some practical utilization according to our\r experimental results.