芯電感應
Based on Ampere,s Law, the magnetic field intensity of the solenoids is B=μ0μr?n?I, where μ0 is the magnetic permeability of free space, μr is the relative magnetic permeability, n is the number of coils per unit length and I is the solenoidal current. The end magnetic field of the solenoid must multiply by one half. According to the above result, it can be greatly strengthened by the addition of a ferromagnetic core. First, we observe three different inserted materials of coils (wood, iron and magnetite), whose magnetic induction in different solenoidial current. By experiment, when the iron and magnetite materials were inserted into the coil, it would produce larger magnetic induction. The calculated relative magnetic permeabilities of wood, iron and magnetite materials are 0.57, 18.37 and 18.32, which are close to the reported paper (1). When the driving field is removed, the fraction of the saturation magnetization of the magnetite is retained, which is called hysteresis and is related to the existence of magnetic domains in the material. In the second part, we change the frequency of circuit switch, which induced different current. Compared with the result of the first part, it would fit the result, which is the induced magnetic field is proportion to the solenoidal current. 根據安培定律,螺線管的磁場為B=μ0μr?n?I。其中μ0為真空中的導磁率,μr為相對的導磁率,n為單位長度的線圈匝數,I則為通入螺旋管的電流。至於螺旋管的端點磁場須再乘上1/2。所以根據上述的結果,當螺旋管插入鐵磁性物質,會增強螺旋管的磁場。首先,觀察三種不同的芯物質;非鐵磁性材料,軟磁材料,硬磁材料(木棒,低碳鋼棒,磁鐵棒)在不同的外加磁場下的感應磁場,得到芯物質的磁化曲線,而計算出來的相對導磁率分別為0.57, 18.37 和18.32與參考文獻(1)接近。而當外加磁場移走時,硬磁性物質的磁性仍然存在,稱為殘磁現象。在第二部分,我們改變線路開關的頻率。發現不同的開關頻率,會得到不同的螺旋管電流,而造成不同的感應磁場。再度驗證了感應磁場大小是正比於螺旋管電流的大小。
Stimuli-responsive Fullerene Grafted Polymers for Enhanced Drug Delivery Applications
The physiochemical properties of fullerenes have aroused wide interest, such as its ability to accept and lose electrons and relatively high reactivity that permit various modes of structural modifications. However, obstacles to further research include its complete lack of solubility in water and low processability.\r This project investigated the morphology and microstructure of a fullerene-grafted polymer as a potential candidate for better and novel systems for drug delivery. In this research, hydrophilic functionalities were introduced to the C60 fullerene by chemical modifications, through the attachment of poly(acrylic acid) (PAA) chain. The objective was to investigate the dynamics and the self-assembly properties of this polymer in aqueous solutions, and the knowledge gained would enhance the development of such system for potential applications in drug delivery and nanotechnology.
天空之城耐震設計與隔震技術之探討
我們的研究包括兩部份,第一部份是實地調查訪問。瞭解地震成因、傷害及現有防震方法,並調查坊間各種建築物類型,及常見私自改變建築物結構現象,做為研究的基礎。第二部份為建築物抗震實驗。研究發現:牆面挖空、頂樓加蓋、樓層挑高,建築物會在該處產生弱點,由此斷裂。柱子數量相同下,散開時支撐力較弱。不對稱建築物遇震時會不自然扭轉且易倒。隔震素材恰當,能有效提高耐震力。滑軌、彈珠隔震效果很好,但位移太大,為實際建築所不容許。建物下加裝阻尼材料,能吸收部份地震能量,降低地震對建築物的危害,並有效控制位移問題,是良好的隔震素材。樓頂加裝消能設施亦能減震,但設計極其不易。 The research includes two parts. In the first part the work is concentrated on on-site visiting and investigation such as understanding the cause of earthquake, the damage and the preventive method currently available, investigating the different types of building and the phenomenon of altering the structure of an existing building without permission by government authorities which is popularly seen in Taiwan. These are considered as the basis of the research. The second part is the experimental study of earthquake resistance of a building. The test results showed that weak-point can be caused at the place where the existing wall is moved or an extra building is attached to the roof or the structure of building has extended space between floors, and fracture always occurs at the weak-point. If the number of columns of a building is the same, then the scattering arranged location of columns is weaker than concentrating type of arrangement of columns. The building having unsymmetrical structure will twist in uneven fashion that causes the building apt to collapse in case of earthquake. Employing proper vibration-absorption material can effectively increase earthquake resistance. Sliding rails and balls can provide satisfiable vibration-isolation effect, but can also cause too much displacement of building structure. Install damping material beneath the building can absorb part of the energy of earthquake, and decrease the damage, and can solve the problem of displacement of building, therefore, damping material can be considered as an ideal vibration-isolation material. Install energy-attenuation equipment can also reduce vibration but the design of the equipment is extremely difficult.
一個也沒漏掉,一個正有理數的排序的研究
本文中我們探討一個有趣的數列。這個數列有一個非常特殊的性質:將數列相鄰兩項的前項當分子,後項當分母,所產生的分數數列,恰好會出現所有的正有理數。 這個特殊的性質表示,可以將正有理數按照這個方式作排序,這個排序將完全不同於常見的正有理數排序的方法。
(1). 在正有理數的排序的結構中,我們做出許多有關於此數列的定理。
(2). 用數學歸納法證明此分數數列涵蓋所有正有理數,且每一正有理數只出現過一次。
(3). 將數列分割後,利用試算表製成數列規則表,並整理出快速的方法將數列表達出來。
(4). 將an 數列排成“樹"的模式,可更快速的把正有理數寫下來。
(5). 最後,設計出搜尋正有理數的演算法,解決在分數數列中第n個正有理數會是多少;以及正有理數會出現在數列中第幾項的問題。
Let’s discuss an interesting sequence. There is a very special quality in it. In this sequence, choose two numbers, which are close to each other, and suppose the first number as “member” while the second one as “denominator.” Then we can get a fraction sequence that includes all of the positive rational numbers! According to this special quality, we can arrange positive rational numbers by the following method. Then we can get a brand-new way of the arrangements.
(1). We can find many theorems about this sequence according to this special arrangement of the positive rational numbers.
(2). We can prove the rule that this fraction sequence includes all of the positive rational numbers by mathematical induction. Furthermore, every positive rational number appears only once.
(3). After dividing this sequence into several parts, we can get a sequence rule list by using trial balance and find a faster method to express the sequence.
(4). Arrange the an sequence by the tree model. By this way, we can get all of the positive rational numbers much faster.
(5). Finally, we can develop the operation method to solve the questions that what position would one positive rational number be in the sequence and what is the first, second, third or nth positive rational number of the sequence.
「天上掉下來的禮物嗎?」—討論十年來大陸沙塵暴對台灣之影響與變化趨?
In recent years, sandstorms have seriously attacked Taiwan day by day. Combining with the observations of Central Weather Bureau and the satellite images of NASA, the study has been collected the data of suspension grain in decades. And the study hopes the sandstorms’ information could be observed in early period. Still it hopes to find out the possible transmission paths in the atmosphere. Then we know how to cope with sandstorms in early time. Sandstorms attack Taiwan frequently in spring, the end of the autumn and the beginning of the winter. Compared with the charts of sandstorms and the satellite images, we could broadly aware that the moving paths of sandstorms are related to the currents and the characteristics of the atmosphere. When El Nino happens, the times of sandstorms attacking Taiwan decrease, and that increase when La Lina happens. According to the results of spectrum analysis, there might be high peaks of a year and six months short period varieties. And low peaks of 2.2 years and 7 months period, tell us that the short period aerosol varieties should be relative with season changes, the long period aerosol varieties may be relative with the El Nino and La Lina period. 近年來,大陸沙塵暴侵襲台灣的情況日趨嚴重影響。本研究中收集了近十年來懸浮顆粒資料,配合環保署空氣品質監測站、中央氣象局所觀測的資料與美國太空總署的衛星影像資料及NASA航空資源實驗室的氣流軌跡回推圖,希望能夠在早期觀測時發現大陸地區沙塵暴訊息,和沙塵暴所帶至大氣中的懸浮顆粒可能傳輸路徑。發生沙塵暴侵臺事件的季節,主要在春季及秋冬兩季交替期間發生的次數為最多。由地面天氣圖表、氣流軌跡回推圖及美國太空總署的衛星影像進行綜合比對之後,可大致瞭解大陸沙塵可能的移動路徑與大氣環流特徵有關。 聖嬰現象(El Nino)發生時,侵襲臺灣的沙塵暴次數會減少。在「反聖嬰現象」(La Lina)發生時,侵襲臺灣的次數相對增加。經由頻譜分析中得知,懸浮顆粒高峰期的變化有1年期及6個月變化趨勢,懸浮顆粒低峰期的週期變化有2.2年與7個月的變化趨勢,顯示短週期大氣懸浮顆粒變化應與季節變化有關,長期性變化或許與聖嬰反聖嬰週期有關連。
Mathematical Analysis of Root Growth in Gamma-irradiated
Root growth is related to the acquisition, distribution, and consumption of water and nutrients of plants. As a vital organ, roots directly take the effect of environmental change and its behavior is closely related to the growth of the whole plant. With such, the importance of root systems has motivated botanists to seek a better understanding of root branching complexity. This complexity, which has been difficult to comprehend using simple Euclidean methods (i.e. lines and circles), is important to the survival of plants, especially when the distribution of resources in the environment is scarce. Mathematical models using fractals and computers can be applied to accurately understand the growth and form complexity of plant root systems. This study was conducted to analyze the root growth of gamma-irradiated cashew and mangosteen using fractals.