全國中小學科展

2023年

Construction of Brahmagupta n-gons by Chebyshev Polynomials

Brahmagupta n-gons是邊長為整數的圓內接多邊形,其對角線長與面積亦為整數,半徑為有理數。而作者發現參考文獻[2,3]建構的完美多邊形其實就是Brahmagupta n-gons經過適當伸縮後,使得外接圓半徑為整數時的圓內接多邊形。 參考文獻「建構邊長為整數的圓內接多邊形」[2] 與「建構三種以上相異整數邊長的圓內接多邊形」[3]是我2020年的作品,我建構了多類兩種以上相異整數邊長的圓內接多邊形的一般式。因為我的建構方法會使得外接圓半徑很大,故本研究先討論在單位圓上邊長為有理數的圓內接多邊形,再將其適當地伸縮後,即可得邊長為整數的圓內接多邊形。 在n倍角公式的研究方法也由隸美弗定理改成使用柴比雪夫多項式做更深層的刻畫,完整的找出多種相異整數邊長且外接圓半徑與所有對角線長均為整數的圓內接多邊形的一般式。

DECREASING CANSAT ANGULAR VELOCITY USING DEPLOYABLE FINS

CanSat (a can-size satellite) flight data revealed the occurrence of high spin angular velocities along the vertical axis of a CanSat during a parachute descent phase. A novel aerodynamic stabilization system of deployable fins was designed to decrease angular velocity. Deployable fins were attached to servomotors (rotary actuators) to provide control authority during the CanSat descent phase. Deployable fins positions were calculated based on an onboard gyroscope data using a PID (proportional-integral-derivative controller) regulator and a moving-average filter. After the assembly and the initial testing, the system was flight-proven by dropping it from a drone with and without enabling the stabilization system

鑑色~藍染動力進行式

傳統藍染,染個深藍色的布,需要反覆侵染二、三十次才行,而每一次洗滌,都是藍水會對環境污染!我們自製鑑色儀器的設計,以白光照射吸光儀,讓光敏電阻感光後,測量一般電阻電壓大小,以不同濃度製作檢量線比較染液濃度;染布鑑色儀則是以GY-33顏色感測器校正後,快速測出色布上同樣區塊面積的RGB值,再利用線上顏色代碼轉換工具,轉換成HSB 值來分析染布顏色。而染布動力的部份我們想把一直都是用塑膠積木製作的二~六槳水車更新成金屬,然後再次比較出不同水位負載物的氧化及還原轉速,希望能找出最佳水車運轉速率及水位高度比,為了因應長度較大的藍巾,水車轉動還加入程式控制順逆轉軸的動力輪替。最後,我們比較增加風速或溫度可否加速藍染氧化之定色,讓精準快速的藍染文化成為可能。

探討多子連線的最小阻隔數

2021年國際科展中,有作品探討鉛直與水平排列的支配數,而本研究從五子棋的想法出發,將前述研究進行重要的延伸與改變,探討在a×b棋盤中,「米」字方向無p子連線時,所需的阻隔數最小值。由於有界棋盤比無界棋盤複雜許多,因此我們先在無界棋盤中找出符合阻隔限制的「完美型態」,並找出存在至少一種「完美型態」的p值集合Ω。研究發現,只要是可以表示為p=6k-1或p=6k+1(k∈N)的正整數p,皆可以型態DT(p,d)阻隔。接著我們推廣至有界棋盤,先探討所有p值的f(a,b;p)上界與下界,再針對Ω中的p值做討論,利用「任意1×p區域至少有1個阻隔」的性質導出「完美型態」下長或寬為kp(k∈N)的下界,並找出非常接近f(a,b;p)的上界。我們也將二維的探討方式與結果延伸至三維,找出所有p值的f(a,b,c;p)上下界與可使阻隔型態DT(p,d_R,d_h)為完美型態的p值集合。另外我們也找出嚴格對角拉丁方陣可對應成「完美型態」之必要條件。

即時觀測核苷酸調控單一DNA 分子上重組酵素的結合反應

在DNA重組反應中,核苷酸擔任輔助重組酵素E. coli RecA蛋白和DNA結合的重要角色,近期研究發現環狀核苷酸 Cyclic di-AMP 和Cyclic di-GMP是細菌內普遍控制複雜細胞活動的二級訊號,因此本研究運用單分子拴球實驗直接觀察單一DNA分子,以布朗運動值反映DNA長度的特性,分析環狀核苷酸參與調控後,重組酵素結合上DNA的反應速率與機制,進而了解環狀核苷酸在調節基因組穩定性的角色。 藉由分析單一種類核苷酸與混合核苷酸的實驗結果,得到兩種環狀核苷酸在重組酵素的結合反應中皆屬抑制劑,大幅降低蛋白結合上DNA的反應速率,且就結構來看,相較一般參與反應的三磷酸腺苷會增加DNA長度,新發現Cyclic di-AMP有縮短部分DNA長度的特質。 由於DNA修復主要倚賴DNA重組反應進行,因此若細菌DNA出現損壞時,加入環狀核苷酸抑制重組酵素結合上破損的DNA分子,使細菌DNA無法成功複製,達到預防細菌擴散的效果。

合成CaMKII抑制劑作為抗癌潛力藥物

鈣及攜鈣蛋白調節酶(CaMKII)存在於大部分細胞中,研究顯示其在多種癌細胞中過度表現。苯基磺醯胺衍生物為CaMKII抑制劑的常見結構,而吲哚與靛紅是常見藥物結構,因此本研究參考文獻[1],並擴展臨床尚未解決問題,優化此兩類衍生物以製成抗癌藥物。第一系列以苯基磺醯胺為主架構,改良文獻[1]中抑制效果最佳的化合物1,第二系列則修改吲哚與靛紅的取代基,設計出多種候選分子。初步利用分子模擬分析軟體(Discovery Studio)模擬蛋白質與藥物分子結合,考量結合能、結合方位、藥物取得及合成難易度,選定有潛力的WACY與CYWA系列結構進行合成。本實驗使用創新的步驟合成,簡易、高效率且符合綠色化學,再經核磁共振與高解析度質譜儀驗證得出高純度產物。最後根據生物檢測發現WACY-2對乳癌細胞毒性高和對於一般乳腺細胞和乳癌細胞的選擇性都較市售抑制劑KN-93佳,而WACY-6對CaMKII抑制效果為WACY系列最佳;CYWA-2, 3, 6, 7對乳癌細胞的毒性和對CaMKII抑制效果又優於KN-93與WACY系列許多。本研究成功製備出符合理論計算預期且抑制蛋白質的效果較KN-93佳的化合物,未來極具潛力作為抗乳癌的標靶藥物。

Utilization of Escherichia coli in Contiminated Water in the Citarum River as a Dual Chamber Baed On Microbial Fuel Cell (MFC) Substrat

Citarum River is the longest and largest river in West Java. The upstream of the Citarum River starts from Mount Wayang, Bandung Regency and ends at the mouth of the Java Sea which is located in Muara Gembong, Bekasi Regency. The Citarum River plays an important role as raw water for PDAM drinking water, supplies electricity in Java-Bali and provides water for rice field irrigation in West Java. Citarum watershed is dominated by the manufacturing industry sector such as chemicals, textiles, leather, paper, pharmaceuticals, metals, food and beverage products, and others. Based on data from the World Bank, every day, the Citarum River is polluted by approximately 20,000 tons of waste and 340,000 tons of waste water with the majority of the waste contributors coming from 2,000 textile industries. By looking at these events, there is no doubt that the sustainability of the ecosystem and the environment in the Citarum River is damaged and polluted. (Zahra Fani Robyanti; 2020). The West Java Regional Environmental Management Agency stated that the content of E. coli bacteria in the Citarum River had increased. The bacteria that cause diarrhea come from industrial and household waste. In addition to E. coli bacteria, other pollutants in the Citarum River that have increased are biological oxygen demand (BOD), chemical oxygen demand (COD) and Suspended Solids. One of the efforts that can be done regarding E. coli bacteria that pollute the Citarum river is to make it as a substrate for Microbial Fuel Cell (MFC). Bacteria present in organic media convert organic matter into electrical energy. The nature of bacteria that can degrade organic media (enrichment media) in MFC produces electron and proton ions. It is these ions that produce an electric potential difference so that energy can be generated. Generally in conventional systems, MFC consists of two chambers consisting of anode and cathode chambers. The two spaces are separated by a membrane where proton exchange occurs. This system has not fully worked with bacteria because only the anode side contains bacteria, while on the cathode side it still works using chemical compounds such as Polyaluminum Chloride (PAC). However, recently MFC has been developed using bacteria at the cathode, or better known as biocathode. Bacteria in the cathode space have the same function as electron mediators that were previously carried out by chemical compounds. In many studies on MFCs, acetate is commonly used as a substrate for bacteria to generate electricity. These chemical compounds are easier for bacteria to process than wastewater. Acetate is a simple chemical compound that serves as a carbon source for bacteria. Another advantage of acetate is that this compound does not cause other reactions to bacteria such as fermentation and methanogenesis at room temperature. Based on this thought, the author will design a study entitled Utilization of Escherichia coli Bacteria in Contaminated Water in the Citarum River as a Dual Chamber Based Microbial Fuel Cell (MFC) Substrate.

液滴懸浮於移動表面現象之探討

液體無固定形狀且往下流。我們偶然得知液滴能在移動表面上維持球型並懸浮數分鐘[1],故設計實驗探討物理機制。設計出能高速旋轉且維持穩定的滾筒,是首要克服的關鍵;而為了解液滴轉動行為,我們學會操作粒子圖像測速法。此研究控制參數包括滾筒轉速、液滴半徑及種類,除了指出過去文獻未討論的重要細節,並嘗試建立解釋此運動行為的物理模型及推導方程式,得到簡單的解析解和物理圖像。 實驗上,相較在靜止液面只懸浮0.27秒,矽油滴在穩定移動表面可懸浮數分鐘,此可用文獻[2, 3]中的「空氣墊現象」解釋。移動表面上穩定懸浮的液滴,傾斜角θ與滾筒切線速度v及液滴半徑r的-2次方呈正比,實驗數據與我們的預測皆相符。液體種類影響懸浮的最低轉速,液滴受的交互作用力也因液體種類而異。未來將分析液滴晃動程度、可保持懸浮的速度區間與液滴半徑之關係。

探討圓及橢圓上的格子點個數之連乘積表達式

在坐標平面上, 坐標均為整數的點稱為格子點,在這篇作品中,主要探討圓及橢圓x^2+sy^2=m上的格子點個數,並且此個數以連乘積表達式呈現,其中s為黑格納數,此時虛二次體Q[√(-s)]的整數環為唯一分解整環(簡稱UFD),由此性質可得到虛二次體的整數環中任一元素的分解有唯一表示法。 首先探討質數p在虛二次體Q[√(-s)]的整數環中的分解性,是根據分解性分成四類,再由四類決定m的不可約元分解,進一步推導出x+y√s i,x-y√s i可能的唯一表示法,再由唯一表示法來計數圓及橢圓上的格子點個數。

雙圓記-探究共邊三角形的外接圓 Journey of two circles -Inquiry of two triangles with common side.

這是一個歷時兩年半鑽研兩共邊三角形外接圓各種有趣關係的探究之旅,透過GeoGebra的輔助,經由(1)觀察圖形及數據形成猜想(2)幾何論證猜想為真的探究歷程。 我們首先探討兩共邊三角形外接圓的圓心位置、半徑、半徑和及連心線的關係,發現並證明出等腰三角形中圓心位置具特殊性、兩外接圓半徑和R1+R2與連心線─O1O2的長度都跟動點D的x坐標呈現函數關係且圖形為雙曲線的一支;據此討論出兩外接圓面積和與原三角形外接圓面積關係,同時發現∆AO1O2~∆ABC且AO1OO2四點共圓。在研究連心線時也發現,當動點D移動時,─O1O2的中點形成一條直線;每條連心線皆與以頂點A為焦點,(BC) ⃡為準線的拋物線相切。最後得出若任意∆ABC的頂點A到─BC的距離相等,連心線─O1O2所包絡出的拋物線皆全等。