The Polar Equation from Butterfly Sprinkler Heads
This project aims to create the polar equations from the relation of the points on the centre line of the water twisted from Butterfly sprinkler heads. The water path includes inner rim, outer rim and centre line laying in the middle of the water path is used Rhombus’s property. The diagonals are perpendicular bisectors of each other to create the centre line. Then we create the polar equation of the centre line of water that twists from 4 types of the Butterfly sprinkler heads: edge frame, curve frame, STL and STL rotary. The polar equation of outer rim and inner rim is created by adding and removing the “ f ” value ( ; is the distance between the outer rim and the centre line, and is the geometric sequence that is ) of the coefficient (a) of the polar equation respectively. The results show that the formal equation of the centre line is which can explain the different properties of Butterfly sprinkler heads. If “ f ” value is increasing the water path and the blade will be wider that affects droplets distributing thoroughtly. Furthermore the relationship between the volume of water and the radius of water distribution can be processed to find the least time that can increase the appropriate moisture level of soil.
費馬多邊形數定理之延伸探討
本研究旨在研究費馬多邊形數定理(任意非負整數必可表成k個k邊形數的和)的一般化情況,也就是說,任意非負整數是否能表成給定的二次多項式數列中所選取的γ項和。以數學模型敘述,就是探討對一個已知的二次多項式an2+bn+c,是否可找到一正整數γ,滿足∀x∈N∪{0},∃α1,α2,…αγ,使得x=∑γi=1(aαi2+bαi+c)。 本作品主要探討若此探究模型存在,那麼數列〈an 〉的一般式an2+bn+c與γ值之間會存在什麼關係,並期望能運用一個簡潔明瞭又一般化的數學式表示。本文亦提供另一個數學模型,探討γ值與某些特殊係數a,b,c之間的關聯性。而本文探尋[a/2]n2+[b/2]n+1,a∈N,b∈Z,a+b≡0(mod 2)(此為本文主要探討的二次式),求得此二次式所對應之γ值的方法為先令p=[2a/(a+b)]+2,再藉由所建立的模型二,求出[(p-2)/2] n2+[(4-p)/2] n的γ值,接著再用所建立的模型一來求得[a/2]n2+[b/2]n+1的γ值,進而依循此方法最後得出任意形如[a/2]n2+[b/2]n+1的二次式之γ值。