全國中小學科展

2019年

從「圓」「點」出發—過定點的圓內接多邊形之研究

此研究在探討「給定一圓及多個已知點,求作各邊或其延長線上恰含有前述已知點中之一點的圓內接多邊形」之作圖方法及圖形的性質。 研究當中,以反演的幾何變換結合代數方程式並透過遞迴關係,除了找到該問題之解的個數與條件外,並求得有唯一解之點的軌跡方程式,從中發現其軌跡圖形為一圓錐曲線,且隨著給定點在圓外個數的奇偶性,會有或為橢圓或為雙曲線之不同的圖形變化。同時也發現給定點本身使得滿足條件的圓內接多邊形存在之個數將決定該軌跡圖形與給定圓間之切點個數等的有趣性質。

The Study of the Relationship between Global Warming and Acid Rain

The purpose of this project are 1)To study the relationship between global warming and acid rain with chemical model and mathematics model from temperature changing and pH of carbonic acid. 2) To create a pH measurement tool of carbonic acid in gaseous state.3) To study the impact of human activities in Loei province that affect to the relationship between global warming and acid rain. The procedures are 1)Do an experiment for studying the relationship between temperature changing and pH of carbonic acid. 2) Proof the mathematics model by using the result of experiment, the chemical reaction equation of carbonic acid solution. 3)Create a pH measurement tool of Carbonic acid by using Arduino and sensor with new formula in the computer program. 4) Using a pH measurement tool of Carbonic acid for studying impact of human activities in Loei province including industrial area, agricultural area, tourism area and forest area. The result of the mathematical model of the relationship between temperature changing and pH of carbonic acid is in form of Cubic equation in Equilibrium state and STP state. (Standard condition for Temperature and Pressure) So, we found that in this state has pH of carbonic acid is about 5.644. When the temperature rises up the effect of rainfall has a lower pH of carbonic acid solution. We also proof the new formula that create a pH measurement tool of Carbonic acid in gaseous state. The impact of human activities in Loei province found that the areas most affected by acid rain are the industrial areas, agricultural areas, tourism areas and forest areas respectively. In conclusion, when the temperature rises, it will dissolve acid solutions in the water on the earth. The loss of [H+] made the pH increases and the greenhouse gases become more atmospheric. These gases are more likely to react with atmospheric vapor. When these vapor form a cloud and condensation falls as rain, the rainfall has a lower pH, that is, global warming can result in the phenomenon of acid rain is greater.

Findings of new oscillations in BR reaction

The Briggs Rauscher reaction, i. e., BR reaction, which is one of the oscillation reactions, produces iodide ion and iodine repeatedly. Continual color changes of the solution from colorless to deep blue, and vice versa, are observed during the reaction due to the so-called “iodine test” reaction. In this work, we studied the effects of the presence of the redox active indicators on the oscillation behavior of the BR reaction. To the reaction mixture of KIO3, H2SO4, H2O2, C3H4O4, MnSO4, and starch, which are used for the general BR reaction as added a redox active reagent (indicator). Then, the changes in color and voltage of the reaction solution were recorded by a photosensor of the LEGO MINDSTORMS and a voltmeter using Pt electrodes. Under general reaction conditions, the oscillation reaction continued for ca. 5 minutes, including 18 times of oscillations. When an indicator, such as BTB, was added instead of starch to the reaction solution, splits of the voltage wave were observed, which should be a kind of new oscillation. Moreover, we found that the addition of K3[Fe(CN)6], which exhibits high redox activity, in the reaction solution instead of starch made the life-time and the numbers of the oscillation in the reaction greater by 3 times (14 min.) in time and more than 4 times (81 times) in the frequency. It’s also a kind of new oscillation. These results suggested that the oxidation-reduction reactions by the addition of ferricyanate ion effectively promotes the redox process of iodine and iodide ion. The experiments we wrote above were conducted without starch. Thus, as a reference, we conducted the same experiments under the presence of starch and got interesting results. We also studied the effects of K4[Fe(CN)6], suggeting that not only redox reaction between ferricyanide and ferrocyanide ion, but also the redox reaction with BR solution should occur in these reactions.

Effect of Air Resonance by Wind Speed Difference on Falling fruit

This study completes an air vibration equation expressed wind speed slope and wind speed. First, preliminary experiments identified air vibrations when wind speed differences occurred over distance. Several air fans were connected in series and the rotational speed of the air fan was adjusted to vary the wind speed with distance. At this time, only certain pendulum oscillates during a particular wind speed slope. It was expected that the pendulum would shake because the frequency of the air due to the slope of the wind speed was equal to the natural frequency of the pendulum. In addition, relatively short pendulum swings in large wind speed slope, long pendulum swings in short wind speed slope. After calculating the natural frequency of the seasonal growth of fruit using the physical factors model, we experiment how resonant frequency was related with cone length, angular width, wind speed, velocity and secondary derivative. the actual experiment analyzed the natural frequency of the fruit and resonance from the air vibration as the linear function of the wind speed, velocity, and secondary derivative. The experiment determined that the pendulum of a specified number of frequencies resonated with a particular wind speed pattern. It is judged that the vibration of air is related to first derivative of wind speed depending on speed and distance. However, it is very difficult to express the flow of nonlinear fluids as a function of simple function, particularly the effects of air vibrations caused by wind speed second derivative, which appeared to be associated with forces. This is a task that needs to be solved through further research.

運用GAN實現字體風格轉換

本研究以實作字體風格轉換的生成對抗網路模型為動機,將Conditional GAN當作模型的基礎,探討pix2pix模型及其他研究的一些方法對模型會產生甚麼影響,以得出能最優化預測成效的深度學習模型。 首先進行的是前處理的步驟,將字體的truetype檔案轉換成模型輸入的jpeg檔,再以生成器(Generator)和判別器(Discriminator)建立Condional GAN的基礎模型,然後探討加入U-Net、Category Embedding等方法,以及訓練資料集大小對模型造成的影響,最後實作整合的pix2pix模型和CycleGAN模型進行比較。 經過實驗後發現,U-Net和Category Embedding都對模型的預測成果有所幫助。另外,對相似的字體而言,pix2pix的效果較好,而對兩種風格差異較大的字體則需用Category Embedding的方式,融入更多字體進行訓練以達到更好的成效。

連續函數與多倍角公式推廣研究

本研究考慮的主要問題: 若非常數之連續函數f滿足∀m∈N,∃P(x)∈C[x] s.t.f(mx)=P(f(x)),其形式應為何? (一)、若考慮函數範圍為解析函數,則f(x)的形式必為下列三者之一: (1).axn+b (2). akx^n+b (3). acos⁡(kxn)+b ,其中a,b,k∈C、n∈N (二)、若將考慮函數範圍改為:連續函數f:[0,∞)→C,則f(x)之形式必為下列三者之一: (1).axk'+b (2). akx^n+b (3). acos⁡(kxn)+b ,其中a,b,k,k'∈C、n∈N、Re(k' )>0 (三)、若將考慮函數範圍改為:連續函數f:(0,∞)→C,則f(x)之形式必為下列四者之一: (1).alogx+b (2).axk'+b (3). akx^n+b (4). acos⁡(kxn)+b ,其中a,b,k,k'∈C、n∈N 在本篇的最後,我們也將N的角色以其他正實數子集取代掉以推廣結果。

圓周上跳躍回歸問題之研究

圓周上相異n個點,將圓周分割成n段弧,每次每個點沿逆時針方向變換成與下一點所成弧之中點,若某點經m次變換後回到初始點,則m的最小值以及m的所有可能值為何?我們發現,m的最小值為n+2。更進一步發現,m的充要條件為m≧n+2且m≠kn-1, kn, kn+1,其中k為正奇數。接著,我們將問題一般化,圓周上相異n個點,沿逆時針方向變換成與下一點所成弧之p:q處,若某點經m次變換後回到初始點,則m的最小值以及m的所有可能值為何?我們發現,若p, q∈N,(p,q)=1,當變換次數r足夠大時,此n個點的位置會收斂至圓周上n等分點,同時,此n個點會在變換T=n(p+q)/(n,p)次後再次收斂至相同的位置。在這篇研究中,我們推導出任意點Pi變換r次後的點之位置坐標Ai(r)的一般式,不失一般性,我們針對P0求出A0(r)的最小極端值Lr與最大極端值Ur,在變換次數r足夠大時,透過觀察Lr與Ur對應到圓周上的收斂位置所形成的區間是否涵蓋原點,可預期P0變換r次後可否回歸。此外,我們也針對n個點具特殊初始位置座標來研究其回歸性質。

當機立「斷」—— 浮萍自裂脫險的機制與生態意義

浮萍在逆境下葉狀體會有分離的現象,本研究證實:浮萍透過葉狀體分離,增加逃離逆境的機率,提升族群生存率。此分離機制受到過氧化物質(H2O2)的調控,逆境下,浮萍母葉節處(node)的H2O2含量上升並誘導細胞死亡,進而造成連接構造斷裂,另能透過乙烯途徑活化纖維素分解酶使葉狀體分離。我們也發現青萍及紫萍具不同生存策略:青萍對H2O2的高敏感度使其能在逆境下快速分離,進而降低其葉狀體間的內聚力,更容易藉由風吹或水流加速逃離逆境;紫萍則對H2O2較不敏感且內聚力大,以較大的單一個體及對逆境的高耐受性來渡過危機。蛋白質含量極高的浮萍是蛋白質補給品的好原料,期待分離機制的深入研究能應用在浮萍種植上,使其快速分離提升產量,應對將到來的糧食危機。

Σn=1∞(n/(Cn2n))=√(x/(4-x)3) (√x(4-x) + 4sin-1(√x/2))與其相關的無窮級數

本文從一個博奕遊戲談起,探討遊戲的期望值得到一無窮級數Σn=1∞n/Cn2n 並嘗試用相關的數學概念與方法思考,首先處理問題Σn=1∞n/Cn2n 與Σn=1∞n2/Cn2n 的值,過程中利用了Σn=1∞n/Cn2n 函數與Σn=1∞n2/Cn2n 函數的性質將欲求之無窮級數轉化成積分或微分方程式的型態,再利用奧斯特洛格拉德斯基積分方法解出所求。 為了更有效率的得到相關之無窮級數,引進了微積分工具中之冪級數的概念,輔以微分方程式公式解求出了 f(x)=Σn=1∞Xn/Cn2n =√x/(4-x)3 (√x(4-x) + 4sin-1(√x/2)), x∈(-4,4), 進而推廣、延伸與其相關的一系列無窮級數,並利用導函數f'(x)求得 Σn=1∞n·2n-1/Cn2n的值。 接下來討論與f'(x)相關的無窮級數,發現可利用f(x)的高階導函數透過迭代方式得到Σn=1∞nm/Cn2n的值,其中m為任意正整數,歸納這些級數後可以應用在本文之博奕遊戲,讓獎金的選擇更富有變化性。 最後觀察f(x)與卡塔蘭數列{Cn}的倒數所構成之冪級數有所關聯,解出 Σn=1∞Xn/Cn的收斂函數後求出了Σn=1∞1/Cn的值以及{1/Cn}的偶數項與奇數項的和。

熊果酸抗胃癌細胞增生與順鉑的協同效應

胃癌的治療方式以手術及化學藥物治療為主。本研究目的是研究中草藥白花蛇舌草的主要成份熊果酸(Ursolic acid, UA)對於胃癌細胞增生的影響。研究使用兩種人類胃癌細胞株MKN45及SCM-1。藉UA處理胃癌細胞之後,由鏡檢可見細胞數目減少,SRB分析法也證明UA會降低細胞的存活率。利用流式細胞儀,證實UA會讓胃癌細胞凋亡。進一步由西方墨點法實驗顯示,UA會誘導促細胞凋亡蛋白Bax及Bak的上升,並且降低抗細胞凋亡蛋白Bcl-xl及Bcl-2的表現。UA也會抑制訊息傳遞途徑p-Stat3/c-Myc/Cyclin D1。實驗也發現UA合併使用化療藥物順鉑(cisplatin)會使胃癌細胞存活率降低。經由周塔氏藥物合併指數及流式細胞儀分析均與協同順鉑能抑制胃癌細胞的增生,西方墨點法也發現pro-caspase 9 被活化,皆與UA會促進順鉑引發凋亡效應有關,這些實驗證實UA是cisplatin治療胃癌的輔劑,這個結果對中草藥白花蛇舌草的抗癌效果提供了具體的實證。