n x n 方格表中的計數問題
對4 × 4 方格表中計數問題的二個解題方法(1..解方程式的方法， 2.分割圖形的方法)作分析和研究後，首先我推廣分割圖形的方法來証明 : “好的n × n 方格表” 存在若且惟若n 為偶數。同時証明這種“好的n × n 方格表”內所有n2 個數的總和f(n) 為n(n+2)/4。當討論一般的n×m 方格表時，發現分割圖形的方法盲點，無法繼續推廣來証明。再經過深入分析與推廣解方程式的方法，藉由n×m 變數方格表，我們終於找到構造所有“好的n × m方格表”的方法。同時計算“好的n × m 方格表” (n≦m)內所有mn 個數的總和f(n,m), n≦7和証明好的nxm 方格表會有2(n+1)行一個循環的現象。We first studied two solution methods (1.solving equations,2.dissecting diagrams.) for calculations on 4x4 checkboard. Using the method of dissecting diagrams, we proved that``good nxn checkboard'' exists if and only if n is even. Furthermore, the sum f(n) of those n2 numbers in a ``good'' nxn checkboard is equal to n(n+2)/4.In studying the more general nx m checkboards, we found that the method of dissecting diagrams does not work, However, by extending the method of solving equations, and by considering nx m variable checkboards, we obtained a way of obtaining all ``good nxm checkboards.'' By way of computing the sum f(n,m) (n≦7) of those mn numbers in a ``good nxm checkboards,'' periodicity in every 2(n+1) rows is observed.
「蓮」「環」密碼--環境因子對蓮花效應的影響
蓮花效應是指蓮葉表面具有奈米纖毛結構，因此只要葉面稍微傾斜，水珠就會滾離葉面，在我們生活週遭，許多植物具有蓮花效應。本實驗選擇彩葉山漆莖作為研究材料，因為我們發現在同一植株上，嫩葉的蓮花效應最佳，而老葉幾乎無蓮花效應。當彩葉山漆莖的新葉轉為老葉，蓮花效應會減弱，甚至消失。我們以不同水量、土壤酸鹼值及光照作為變因，來探討蓮花效應改變的原因，結果發現水量並非主要影響蓮花效應改變的變因；土壤過酸或過鹼，會減弱新葉及嫩葉的蓮花效應；置於暗室則使整株彩葉山漆莖所有葉面皆無蓮花效應。許多植物的性狀，在老化或面臨環境改變時，會將控制性狀的基因開啟或關閉。因此，我們推論，當環境因子改變時，植物的蓮花效應可能是經由基因層次的調控，藉以增強或減弱此性狀的表現。如果不是基因的開啟或關閉，則有可能僅是葉表面的結構發生些微的改變，真正詳細的機制仍有待進一步的確認。;We choose Breynia nivosa (Bull ex W. G. Smith) Small as a model plant to study the lotus effect on the leaves for the reason that on the same chosen plant the new-born leaves have the best lotus effect while the elder ones have little lotus effect. When the new leaves turns into elder ones, the lotus effect also turns weaker or even vanishes. To explore the exact mechanisms, we take water quantity、soil pH、and light density as the experimental factors. The results show that water quantity cannot affect the lotus effect on all leaves, change in soil pH can decrease the lotus effect on the new and new-born leaves, and dark treatments can eliminate the lotus effect on all leaves. When the environments change, the phenotypes of plants could also be changed to adapt to the new conditions by turning on or off genes. Therefore, we suggest that the lotus effect on the leaves is also controlled by genes to increase or decrease its phentype so as to adapt to the changing environments. If not, it may simply be a little change of the surface structure of the leaves. The detailed mechanism remains to be confirmed further.
漩渦也有形
流體旋轉時，外圍及底部流體，因槽壁及槽底摩擦力的影響，流速較慢，相對的壓力也較大，導致外圍的水流會轉入中心。發現本實驗的渦流為強迫與自由漩渦組成。實驗中，探討f(轉動器的頻率)、H(總水深)、y(?入深度)、R(轉盤半徑)四者與角形數間的關係。若y、R 愈大、H 越小，隨著f 的增大，可觀察到的形狀邊數越多；反之，若y、R 愈小、H 越大，則f 愈高，所形成的圖形半徑愈大，易超過轉盤，不易觀察。依白努利方程式，外層水流的流速較慢，而內層水流的流速較快，故外層壓力大而內層壓力小，水會由外往內流，而此渦動流於轉動液面產生的剪力，可能為產生N 邊形漩渦的主要原因之一。流體旋轉系統中，因轉動而產生流體離心力與內外層壓力差交互作用下，於某特定相關的因素條件下，形成特定角形數漩渦，是本實驗的重要發現。When fluids are in rotation, fictitious force given by the container brings about the relative decrease of speed of the bottom and outer layer of water, which causes its pressure to increase, and water to spin inward, resulting in a vortex motion with N-corner polygons formed at the surface of the rotating plate. During this experiment, we discover that the vortices consisted of free and forced vortex and the polygons vary as control parameters f(rotation frequency), H(height of fluid), y(depth of the plate), and R(radius of the plate) change. The larger y and R are,the smaller H is, the more corners show up as f increases. On the contrary, the smaller y and R are,the larger H is, few polygons are identified since the rotating radius of polygons are larger than the plate. According to Bernoulli’s principle, smaller velocity of the outer-layer water causes water pressure to increase and water to spin inward. During this process, shear force is developed at the surface of the rotating fluid, which we believe is the main cause of N-corner polygons. In a rotating system, the interaction of centrifugal force and differential pressure causing a certain Ncorner polygon to be formed under different controlled parameters is our main discovery.
宇宙演化的黑手
We study the effect of dark energy on the evolution of cosmic structure in a scenario where the dark energy is treated as free particles and thus can be localized. By theoretical derivation and numerical simulations, we found that:
1. The dark energy particles gain kinetic energy from a moving dark matter particle through gravitational interaction. Due to energy conservation, the dark matter particle will slow down with time
Ek(t) = Ek0 - 9 × 10-5[|1+3w|ρDE]1.92t where Ek(t) is the kinetic energy of the dark matter particle,Ek0 is its initial kinetic energy, w is the coefficient of equation of state for dark energy, ρDE is the mean energy density of dark energy, and t is the time.
2. The formation history and structure of galaxy clusters are different in the presence of localized dark energy. The more the localized dark energy, the earlier the formation of the cluster core. In addition, the kinetic energy Ek(R) as a function of R will be different if the ρDE is different. Thus we can compare the observed Ek(R) of clusters with our results to deduce the ρDE in our universe. The results here can be applied to the observations in the near future.
我們探討宇宙結構演化受到可局部叢集之黑暗能量粒子的影響。藉由理論推導及電腦模擬，我們發現：
一、黑暗能量粒子會透過重力交互作而從運動中的黑暗物質粒子獲得力學能。因力學能守恆，黑暗物質粒子的速率會減慢，滿足
Ek(t) = Ek0 - 9 × 10-5[|1+3w|ρDE]1.92t
其中Ek(t) 為黑暗物質粒子的動能，Ek0 為其初始動能，w 為狀態方程式係數，ρDE 為黑暗能量的平均密度，t 為時間。
二、星系團的形成過程及結構，會因可局部叢集之黑暗能量的存在而改變。黑暗能量越多時，星系團的核心會越早形成。而且動能 Ek(R) 隨著至星系中心距離R 的變化，會因 ρDE 的不同而不同，因此可以將量測到的 Ek(R) 和這裡的結果比對，推導出宇宙中的 ρDE 。 這些研究成果將可直接應用在未來的觀測結果上。