全國中小學科展

未代表出國作品

蜘蛛數

We understood the definition and meaning of spider number by reading〝Wonders of Numbers〞. It interested us so much. So, we took further step to study the situation of extreme value when the gap sometimes lie on the line and sometimes on the circle or even on both. That is to say, we explored the relation between spider number and the gap when the spider number is maximum or minimum. New research for the application of spider number involves several directions. First, we design a new game called〝Stepping Land Mine〞with the rule of spider number. Give you a net with several hidden gaps, trying to find the right positions of gaps. Second is the further result for a different type of net about regular n-polygon. Third is a tactic for a net with destroying of the strategy points. In this situation, the gaps amount on the circle and on the line are fixed. At the same time, consider the situation of circles and lines designing the tactic of placing the gaps to attain the maximum of the destructive effect. 在本文中我們定義一個蜘蛛網上的蜘蛛數,若在蜘蛛網中加入缺口後,會影響蜘蛛數的大小。我們探討蜘蛛網上的缺口,該如何分配才能夠得到蜘蛛數的極值(最大值及最小值)。先觀察一直線和圓上缺口如何放置蜘蛛數有極值,再探討許多條直線及圓上的情況,進而推展至許多同心圓及通過圓心的許多條放射線的缺口,該如何放置,蜘蛛數才會有極值發生。

漂浮的油滴--CMC 的測定

Surfactants have a great effect on decreasing the surface tension in aqueous solution and thus they are important components in detergents. The present study aims to explore the cleaning mechanisms of the substances for greasy subjects such as bowls and clothes. The roles of various surfactants that have on the changes in the surface tension of aqueous solution in the presence and absence of additives such as tea and salt have been carefully studied by using a lab-made equipment. We carefully observed the changes in the oil droplets after pushing oil in a syringe to the aqueous\r solution containing surfactants and additives. With decreasing the surface tension of the aqueous solution, the size of the droplet becomes smaller. By using this simple lab-made equipment, we are able to determine the critical micelle concentration (CMC) of sodium dodecyl sulfate (SDS), with a result of 0.0079 M at 20 ℃. The result is in a good agreement with the literature (0.0077M). With decreasing temperature and adding salts such as sodium sulfate, the decreases in the surface tension have been confirmed by our simple experiments. This simple equipment also allows study of the effects of impure additives such as salt, tea, vinegar that have on the changes in the surface tension of aqueous solution containing commercial detergents. We have found that most of the additives have a great effect on reducing the surface tension of the aqueous solution. The present study results suggest that the simple experimental set-up is practical for measuring the CMC of surfactants and for exploring the effects of additives on changes in the cleaning ability of commercial detergents.界面活劑性可有效降低水溶液的表面張力,因此,他們是清潔劑的重要成份。該實驗主\r 要在探討各種物質的清潔機制。利用自製的實驗裝置,針對各種不同的界面活性劑在添加了鹽類或茶水後界面張力的改變量,作詳盡的探討。我們將含有不同濃度界面活性劑以及添加物的水溶液裝入容器中,在推擠針筒使其的油通過針頭並進入該溶液後,我們仔細的觀察紀錄油滴大小的改變。結果顯示界面張力的降低會使得油滴變小。藉這個自製的裝置,在20℃下,本實驗所測得的陰離子型界面活性劑-十二烷基硫酸鈉之臨界微胞濃度0.0079M。結果幾乎與過去的文獻0.0077M 值符合。該實驗同時也證實了降低溫度,添加了鹽類後,可有效的降低界面張力。此外,此實驗裝置也可以用來測量市面上販售的清潔劑在添加了不純的物質後,其界面張力的改變量。我們發現大多數的添加物都能有效降低界面張力。目前的實驗結果顯示,這項實驗裝置在測定臨界微胞上有很高的實用性,同時也可以探討不同的添加物對市面上販售的清潔劑之洗淨力的影響。

死亡巧克力—切切割割好計謀

三角形的邊上取任意多個點,我們可以把這塊大三角形沿著切割線切割成較小塊的三角形,但切割線必須是點(或頂點)和點的連線,而且必須切割三角形,同時可以切任意大小的三角形,如圖(1)與圖(2)。但不可以一開始就取走整個三角形。定義拿到最後一塊三角形的人獲勝,而在多邊型中的玩法與在三角形中相同。 我們分A、B、C三種規則來討論,其中A規則即是上面提到的玩法,B規則大部分的玩法和A規則都相同,唯一不同的地方在於:A規則中,只要有一方取到剩下的圖形為三角形,另一方就可以直接取走剩下的三角形,而B規則規定即使剩下的圖形已經是三角形,也必須取到剩下的圖形邊上都沒有分點為止。C規則是限制玩家一次所能取的三角形數來進行遊戲。 我們完成了A、B、C規則中三角形與多邊形的必勝策略,並找出必勝策略之間的關聯。 ;Given any numbers of points on the sides of a triangle, the players can cut this triangle into pieces. Each cutting line has to be one, linked between two points given from two different sides. And the player can’t have to cut smaller triangles out of the original triangle. The out-cut triangles can be chosen randomly without any restriction in size, just like what’s shown in picture(1)and(2). Meanwhile the first player can’t cut the original triangle exactly all out in the very beginning process. We define the player as the winner, who gets the last triangle. And the above way we play can be applies to any multi-side shapes. We discussed the question respectively in three rules, A, B, and C. Rule A is what we mention above. Rule B is generally the same as rule A, except for the only difference:The rule A , if there is any triangle left , the next player can get it directly, but while in rule B, the every next player has to cut out smaller triangles until no point is left on sides. Rule C proceeds on conditions that there is a limitation to a certain number of triangles cut out at a time. We has finished the winning tactic respectively in rule A, B, and C in the games with a triangle and multi-side shapes. Furthermore, we find the connection between the winning tactives.

蟹狀星雲的擴張

By comparing eight different epoch images of the crab nebula taken through 1942 to 2004, we have calculated the expansion velocity of 27 optical bubble features and 60 filaments. The mean expansion velocity of bubble features and filaments is 0.173 arcsec/yr and 0.15 arcsec/yr, respectively. We also estimated the maximum radial velocity of the expansion by analyzing the emission spectrum of the nebula. The maximum radial velocity is 1385.5 km/s. Combining these measurements indicates that the crab nebular is approximately 5870 light year away. In addition, if we assume that the nebula has been expanding at a constant rate, our expansion velocity projected backward indicates the mean date of the supernova event as A.D 1124, more than 70 yrs later than the accepted date of 1054. The result confirms the well-known acceleration in the crab's expansion. Although we have analyzed eight images with a 62 yr baseline, the acceleration still can't be derived from this study. 透過量測由1942年到2004年之間八張不同年代的蟹狀星雲中爆炸後殘骸的位置變化,可以計算出蟹狀星雲爆發的擴張速度。本研究選定了27個包狀物和60個纖狀物,計算出的擴張速度分別為0.173 arcsec/yr.和0.150 arcsec/yr。再透過分析蟹狀星雲的光譜所計算出的徑向速度(radial velocity)為1385.5 km/yr,進而推得蟹狀星雲的距離分別為5430光年和6370光年,平均值為5870光年。 另外,如果假設擴張速度是等速運動,那麼把求得的擴張速度倒推出的爆發日期是在西元1124年,這比中國紀錄中超新星爆發的1054年晚了70年。這顯示出蟹狀星雲的確非等速擴張而是有加速度的狀態,才會造成以等速倒推發生日期時,晚了70年。雖然本研究中分析了相差62年之久的八張影像,仍然無法分析出星雲的擴張的加速度情形。

完全圖立方乘積之最小控制

完全圖Kn是指一個圖中有n個點,且任意一個點都跟其它的點有邊相連。兩個圖G和H的卡氏乘積G□H的點集V(G□H)={(g,h)| g∈V(G),h∈V(H)},兩個點(g1,h1)和(g2,h2)有邊相連若且為若g1=g2 且h1~h2,或g1~g2且h1=h2。 三個完全圖Ka、Kb、Kc 的立方乘積是指Ka□Kb□Kc。一個圖G中的一點v所連的其它點稱為這個點v的鄰居,也就是N(v)={x | x~v}。一個點集S中的所有點的鄰居的聯集稱為這個點集的鄰居,也就是N(S)=∪v∈S N(v)。如果一個點集S和它的鄰居N(S)包含了一個圖G的所有的點,也就是S∪N(S)=V(G)稱這個點集S是這個圖G的一個控制集。我們把圖G的所有控制集中點數最少的稱為最小控制集,並定最小控制集的點數為最小控制數γ(G),也就是γ(G)=min { | S |, S是G的控制}。 本文的目的在於研究完全圖立方乘積的最小控制,也就是要給γ(Ka□Kb□Kc)一個上界。特別當 a = b = c = n時,γ(Ka□Kb□Kc) = 。 A complete graph Kn is a graph with n vertices, which any vertex is adjacency to every other vertices. The Cartesian product of two graph G and H which is denoted G□H is define as follow: the vertex set V(G□H)={(g,h)| g∈V(G),h∈V(H)},and two vertices (g1,h1) and (g2,h2) is adjacent if and only if g1=g2 and h1~h2 or g1~g2 and h1=h2. The Cartesian product of three complete graph Ka,Kb,Kc is Ka□Kb□Kc,which is the same with (Ka□Kb)□Kc. In a graph G, the neighbor of a vertex v N(v) is the set of the vertices adjacent to the vertex v, that is N(v)={x | x~v}。 The neighbor of a vertex set S is N(S), which is the union of the neighbors of vertex v over S, that is N(S)=∪v∈SN(v). For a graph G, if a vertex set S unions its neighbor N(S) equal to the vertex set of G, that is S∪N(S)=V(G), we say that S is a dominating set of G. The domination number of a graph G will be denoted as γ(G), which is the minimum size of all dominating set of G.. We give an upper bound to γ(Ka□Kb□Kc). And when a=b=c, γ(Ka□Kb□Kc) ≦

「膠」流電-黏度及外加電壓對電解質溶液離子暫穩態通道之影響

在本次實驗中,我發現膠狀電解質溶液中的帶電離子,會因為離子團的熱運動,和電偶極的庫倫吸引力 (electric dipole) 的交互作用下,使溶液的I-V curve (電流-電壓曲線),具有類似磁滯曲線(Hysteresis curve) 的效果;而膠狀溶液之濃度越高,電解起始點的對應I-V 值也越大。此外,白金電極與銅箔電極的距離若改變,也會使溶液的I-V curve 變的不一樣。另一方面,我也發現,在給予膠狀電解質溶液一緩慢外加的電壓或衝擊電壓並持續維持此一定額外加電壓時,會因為該溶液的黏度持續增高、帶電離子濃度增高且反應不斷變化下,而使該溶液的對應電壓,形成一重複出現「先降-後升-再降」的震盪現象,且電壓值節節升高。最後,我利用掃描式電子顯微鏡(SEM)及能量分散光譜儀(EDS)觀察銅箔電極之表面變化並分析其上之化學組成,藉此嘗試解釋上述這些有趣的現象。In this experiment, with the interaction of the heating action of ionic atmosphere and electric dipole, I find that ions in the gel make the I-V curve in the colloid electrolyte liquor show up with the effect similar to Hysteresis curve. The higher concentration of the colloidal solution, the bigger value of I-V at the initial electrolysis reaction was found. Furthermore, the shape of I-V curve is dependent on the distance between platinum electrode and cupper electrode. On the other hand, I find that when I apply a gradual extra-voltage or a fast extra-voltage to the colloidal electrolyte solutions and then maintain to a fixed value, this will make a unique ‘two peaks’ state oscillation of corresponding voltage. The reason is owing to the climbing viscosity and ion concentration in the solution. With the methods of scanning electron microscope (SEM) and energy dispersive spectrometer (EDS), I observe the change and analyze the components of chemicals on the surface of the cupper electrodes. Finally, I present the interesting results and try to interpret these phenomena.

Self Assembly Mechanism of Water Droplets

這是一系列關於水蒸氣冷凝為極細微水珠的實驗。其中可以歸納為三大部分,第一部分是基礎實驗,將水蒸氣導引至親水性介面上,觀察冷凝水珠的結構。雖然看似簡單平常,但是卻發現:不同溫度的水蒸氣,其冷凝最初始的細微珠粒,尺寸相同;爾後溫度高者,堆疊速率較大,以至於最後同時呈現的水珠大小不一,尺寸不同! 第二部分,是針對冷凝水珠自我組裝機制的探討。實驗是將水蒸氣導引至密度小於1的高分子溶液上,並藉由揮發性溶劑快速揮發,將水珠粒「分層保留」以便更深入了解「解構」後的水珠群聚機制。在這組實驗中得到兩張有趣的圖片: 在討論時,我是從對流機制切入,嘗試解構上面兩張圖。 第三部分的實驗,是將水蒸氣導引到磁場及靜電場上,觀察冷凝的機構。這部分呈現出來的結果,推翻了一般「水分子為電中性應該在電場與磁場中不受影響?」刻板觀念,實驗呈現水分子:不但在電磁場上不易長大同時也有固定的散佈模式(assembly pattern)。同時也觀察到:水分子在正電場形成的凝結水珠較為均勻,在負電場則表現出較大親水性特質。這部分的實驗對日後研究細胞膜上水分子通道應有助益。 I have tried to ask a famous math professor if he can create a formula describing the ordered array of water droplets. “Then, I should study Physics first!” He said. Condensation is the thing we live with, being found everywhere, passing without notice. But we never know when it dose start? By coalescence, water droplets grow bigger, but are not round again. We used the polymer film as template and designed the solution lighter than water, so the minute droplets will sink to the bottom and layer by layer. After seconds we may have multilayers of ordered array. This experiment presented here is actually the diary of the growth of water droplets through condensation, upon volatile fluid, magnetic field and electric field. Through convection, it discusses the self assembly mechanism of water droplets and peep into the uniformity of the size of water droplets. In this experiment, convection and magneto-electric force did play important roles in the self assembly mechanism of water droplets. The topic is mostly concerned as we are surrounded by magneto-electric waves in today’s world. This is the first step in discovering the homogeneous state of water droplets, providing insights into the self assembly mechanism of water droplets with nano sizes.

流體碰撞物體所產生的波形之研究及應用

當流體由圓管流下,在碰撞到物體後水流會產生類似駐波的形狀。為瞭解此現象的產生機制,及影響此現象的變因,我們改變流體的表面張力、流速及與碰撞物體間的距離,以探討各變因對波形所產生的影響,進而研究此現象的成因。由實驗結果發現波形會因流速加快、擋板距離增加、表面張力減少而有波長變短的趨勢,且可以用表面張力波的理論解釋。由理論推導的結果,可測量液體表面張力。由於圓球狀的外型使表面積增大,可增加液體之散熱的面積,因此可應用在水冷系統方面。A phenomenon similar to the standing wave, which occurs when a slow-velocity fluid jet collides with an obstacle, was observed. Because the free surface profile was observed to be stable, the phenomenon was not considered as standing wave. To understand the mechanism of this phenomenon and the factors that can affect the free surface profile, the surface tension of the fluid, jet velocity and the distance between the exit of the tube and the obstacle are varied to study their influences on the free surface profile. According to our experiment, the wave length is shortened when the jet velocity or the distance between the tube and the obstacle increases or when the surface tension decreases. The tendency of the investigated phenomenon can be explained by the capillary wave theory. Based on Bernoulli’s principle, continuity principle and surface tension\r equation, an ODE (ordinary differential equation) could be formulated. By using numerical method to solve this ODE, we predict the free surface profile which could match the experimental photo well. The tendency of the phenomenon can also be explained by the ODE. In order to measure the surface tension of the fluid, we wish to minimize the experiment apparatus. To enhance our assumption we use laser to locate the individual particle that we add in the fluid and calculate the velocity field of the flow jet.

利用雙雷射精密測定準靜物的極微小變位

To-be static objects, such as bridges, volcanoes, seldom move ordinarily but have mini displacement only under special conditions, like flood or earthquakes. Therefore, how to measure their mini displacement has never become fully popular with scientists’ research. Then, beginning with “ Optical Lever Theorem”, through a series of speculation and discussion, I decide to use laser ray as light source to perform an experiment ------- trying to find objects with mini displacement in our daily lives, such as revolving electric fans, engine-opening motorcycles, shaken trees, testing their magnifying effect first. Next, I try to use the control-experiment method to find out the magnifying relation and formula of the rotation angle of the plane mirror and the displacement quantity of light focus. As to the measure of mini displacement on objects, I utilize the pillar mirror as a reflection plane to research the magnifying relation of reflection light focus and original displacement quantity. The image made from the light focus of pillar mirror’s reflection, however, isn’t so perfect that I have to use a special plastic-made light-concentrating mirror, which is also called “ Fresnel Lens ”, to focalize the light for easy observation. Besides, I find out the “ function graph ” of the mini displacement quantity on to-be static objects and the displacement quantity of reflection light focus. At last, I try to build up a “ Bridge Alarm System ” of Optical Lever Theorem. 準靜物如橋樑、火山,由於平常不輕易移動,只有在特殊情況下(如洪水、地震)時,才會發生位移的現象。因此,其微小變位如何測量,一向是科學界較少探討的題目。於是,先由光學槓桿原理著手,經過一番思考、探討,決定採用雷射光作為光源,並作了第一個實驗--找生活中具極微小變位的東西,如轉動中的電扇、引擎發動的摩托車、被搖動的樹木等,先測試其放大效果。接著就試圖用控制變因的方法,找出平面鏡旋轉角度和光點平移量的放大關係和公式。至於物體微小的平移量之測量,則是利用柱面鏡作為反射面,來探討反射光點的位移與本來的平移量之放大關係。然而,柱面鏡的反射光點成像並不理想,於是用一種特製的塑膠集光鏡,又稱Fresnel Lens,將光點集中以利觀測,並且找出準靜物之微小平移量及反射光點的位移量的函數圖形。最後,嘗試建立一套光學槓桿式的「橋樑預警系統」。

新型空氣清淨燈具之研究與開發

本研究主要的目的是在開發同時具有空氣清淨與照明的兩種燈具。其中桌燈是基於自然對流原理,利用燈泡發熱讓氣流通過燈具上方的濾網達到過濾功能,為了尋求過濾效果與照度兼顧的最佳值,本研究並提出比較因子的概念。在吊燈方面,除了運用自然對流原理之外,還更進一步利用太陽能驅動風扇,進行強制對流,強化過濾的效果,使得本研究成果更趨於完善。 由實驗結果可得知,桌燈在四星期長期測試條件之下,其過濾效果增進率分別為39.1, 40.8與 40.1%。在吊燈四週長期實驗的結果方面,螺旋與 100W 鎢絲燈泡在自然對流的過濾效果增進率分別為49.1%與 51.4%,而100W鎢絲燈強制對流方面過濾效果增進率則為60.2%。由整個研究結果可以發現,本燈具對於空氣清淨有極佳的效果,在不增加額外耗能條件之下,能增加燈具的散熱效果與延長壽命,同時又具備空氣清淨效果,對環境空氣品質具有相當的貢獻。 The purpose of this study is to develop a novel lamp with both the functions of air-cleaning and lighting. One of it is the desk light. Basing on free convection principle, it makes the air run through the filter on the top of the lamp by its heat in order to attain the aim of air cleaning. To find the optimum value of both cleaning effect and illumination, we advanced the compare factor. The other is the droplight, though it is based on the same principle, we use the solar energy as its power to drive the fan. So that the effect of the filter can be augmented and the result of this research approach perfect. According to the experimental result, in the four-week experiment with desk light, the enhanced efficiency of filter is 39.1%, 40.8% and 40.1% respectively. On the way of droplight with four-week experiment, the enhanced efficiency of filter is 49.1% and 51.4% with helix and tungsten(100W) lamp under the condition of free convection; the enhanced efficiency of filter is 60.2% with tungsten(100W) lamp under forced convection. All these results of the research shows that the novel lamp has great performance on air cleaning and much better effect of heat sink without extra consuming of energy, also the lifespan of the lamp can be extended. Furthermore, it is capable of air cleaning and contributes to the quality of environmental air.