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二等獎

基於睡眠時期大腦活動之概念的類神經網路優化法研究

深度學習透過迭代的訓練,如沿著梯度反方向更新權重的梯度下降法,旨在找出損失函數建構出的多維函數圖形中,其全局最小解的變數組合。我們受到在睡眠中的快速動眼期啟發,此時期腦中的高頻率γ波可以強化學習效果。本研究模擬此現象,提出一使原損失函數擁有自適應的增幅功能的演算法(稱之為REM方法),且其中的超參數能夠根據其應用調整。 本研究將REM方法應用於三種經典的優化法,並且以五種異質的資料集測試。實驗結果指出,在搭配隨機梯度下降法(SGD)與自適應學習率優化法(Adagrad)時,REM有顯著的優化效果。REM方法不僅能大幅加速訓練進程,亦能避免特定的訓練問題。

應用仿生機器人於蜂鳥起飛行為之研究

本研究利用仿生機器人(Biomorphic robotics)來探討蜂鳥(hummingbird)在不同重量變化下的飛行機制。本實驗利用了使用多連桿結構組成的仿生蜂鳥機器人,並使用懸吊裝置來模擬不同重量的蜂鳥,再藉由慢動作高速攝影機來紀錄蜂鳥振翅飛行的過程。透過影像分析與紀錄重量變化來分析仿生蜂鳥拍翅時的動態行為後,我們可以得到與仿生蜂鳥重量相對應的上升力結果與不同蜂鳥重量下相對應的拍翅頻率數據。我們從這些關係分析作圖並推導出對應的公式,這些結果可以解釋為何大部分蜂鳥重量都介於10 - 20克以及拍翅頻率介於20-50Hz,目前尚未有文獻發現及探討這些相關現象的研究,此研究的結果可作為未來微型撲翼機(ornithopter) 的設計參考,有助於微型軍用探測機械與小型空中救援機械的發展。

神農菌、嚐百草-利用基因轉殖的大腸桿菌偵測中草藥內的重金屬

中藥一直存有重金屬汙染的疑慮,而目前檢驗這些可疑重金屬的儀器與技術皆需耗費大量金錢與時間,因此研發出簡便快速的偵測工具極為迫切。本研究目的是利用基因轉殖的大腸桿菌,偵測出中草藥內的重金屬。 實驗結果顯示,利用含有銅離子基因轉殖的大腸桿菌,偵測7種常見的中藥材浸膏,除了黃岑之外,其他6種中藥材內可偵測到銅離子,並且具有定量的螢光表現。其中,研究發現由於黃岑本身會有吸附銅離子的現象,因此利用螯合劑EDTA來解決此問題。結果顯示,螯合劑不會影響大腸桿菌的正常代謝,但能成功地將銅離子搶出並誘導細菌產生螢光。最後利用螢光顯微鏡觀察,發現深色的中藥並不會影響大腸桿菌的螢光表現。 未來期望可將本研究初步成果,做更進一步的研究,除了能合成更多不同基因的大腸桿菌,以偵測不同種類的重金屬外,還製成便宜且方便使用的重金屬生物感測器產品,方便民眾檢驗手中的中草藥材,確保所使用的中草藥之安全性。

小花蔓澤蘭活性成分Dihydromilanolide誘導胃癌細胞凋亡與自噬性死亡

外來入侵種小花蔓澤蘭繁殖速度太快,使台灣本土生環境及多樣性受到破壞。我們研究發現,小花蔓澤蘭葉萃取物會誘導人類胃癌(AGS)細胞毒性;以HPLC分析及分離出小花蔓澤蘭葉萃取物的活性成分Dihydromilanolide (DHK),發現DHK會毒殺胞胃癌、卵巢癌、乳癌與血癌細胞,其中以胃癌(AGS)細胞毒殺性最強。此外,抗氧化劑N-acetylcysteine可減緩小花蔓澤蘭葉萃取物及DHK對胃癌細胞毒殺性,推測是透過活性氧化物(ROS)來毒殺胃癌細胞。我們亦發現,DHK可與抗癌藥物(Doxorubicin、Cisplatin或Paclitaxel)對胃癌細胞產生協同作用。DHK作用胃癌細胞會誘導Caspase-3增加、PARP蛋白裂解、促凋亡Bax增加及抑凋亡Bcl-2減少;產生酸性囊泡(AVOs)、促自噬LC3-II及Beclin-1蛋白增加,且加入自噬抑制劑 3-MA可保護DHK誘導胃癌細胞死亡。推論 DHK可誘發胃癌細胞凋亡(Apoptosis)及自噬性死亡(Autophagy)。總結,小花蔓澤蘭與活性成分Dihydromilanolide (DHK) 具抗胃癌功效且與抗癌藥物產生協同作用,可開發成抗癌的藥品或保健食品。

Design and Prototyping of a Low-Cost Ventilator for Rural Hospitals

This report includes the design and prototyping of a portable automatic bag-valve mask (BVM), or commonly known as the Ambu bag. This development is for use in emergency transport, resource-poor environments, and mass casualty cases like the COVID-19 pandemic. This device replaces the need for human operators whose job is to squeeze the BVMs for extended periods of time. The prototype is made from a stainless-steel skeleton, measuring 470 x 240 x 230 mm, with the addition of acrylic coverings. A repurposed motor from a car is used to drive the squeezing arm. The speed of the arm for inspiration and expiration along with the pausing time between each breath can be adjusted with this prototype. It also features an LCD screen to display the arm speed, along with real-time pressure graph displayed on both phones and computer monitors. For future versions, an app is to be developed to enable the control of the automatic bag-valve mask from phones and tablets, further creating ease for users and increasing portability. Additionally, important requirements will be added: alarm system for over pressurization, control for inspiration to expiration ratio, number of breaths per minute, control for tidal volume, pressure relief valve, and assist-control mode. The cost of this prototype is approximately $430. With this design of an automatic BVM, it allows for the production of a ventilator-like technology that will be able to perform main functions of basic ventilators at a fraction of the current cost.

波濤洶湧的玻璃杯—玻璃杯共振之研究

一個裝有水的玻璃杯,用喇叭撥出大聲的聲音,便能觀察到共振的現象發生,玻璃杯將會不停的震動,甚至導致破裂。本研究將會藉由傅立葉轉換(Fourier transform)來分析玻璃杯的振動的本徵頻率,並進一步探討頻譜的峰值。另外我們也研究了不同水位的高低以及液體密度對於共振頻率的影響,並以能量守恆的觀點進一步推導出玻璃杯的震動方程式。最後我們也近一步討論higher harmonic,並且發現non-linear dispersion relation的現象,有別於我們對於f∝n的觀念。

Potential Diagnosis of Cancerous Cells Through Utilising Optical Spectroscopy

Cancer is responsible for an estimated 9.6 million deaths in 2018. Deaths from cancer worldwide are projected to reach over 13 million in 2030. Thus, developing a device that has the capability to solve today’s toughest global challenge is crucial by utilizing a simple yet robust approach - “SEEING THE UNSEEABLE” through bold innovation. Although removing cancer is much more effective than either radiation or chemotherapy, when unseen residual cancer cells remain, they could grow back into tumour overtime. The reoccurrence of cancer contributes to a greater risk of death. Hence, launching a system that is able to distinguish between the cancerous cell and normal cell is ultimately essential to make sure no cancer is left behind during surgery. This robust optical system is established with quantitative approach by exploring the integration of an algorithm into the developed software. The end result of this device has the capability to provide users an accurate numerical pH value. The developed system is integrated with the smart IoT gateway capability whereby this powerful analytical device is incorporated with the real-time monitoring, data transformation and data analyzer. Harnessing the power of technology lets us fight cancer better. Each time a pathologist analyzes tissue after operation, it can take up 2 to 3 days because the tissue has to be frozen, thinly sliced, and stained so it can be viewed under the microscope during the process of biopsy. Thus, it is crucial to invent this Surgeons’ VisionMetric device which has an IoT-based microcontroller that is capable of providing real-time numerical value on-site.

奈米鑽石性能對於重金屬吸附之應用

奈米鑽石之多官能基、介面電位負值(PH=7時)…等性質使本組考慮其吸附重金屬離子之可行性。本研究目的在於利用奈米鑽石吸附重金屬離子及探討重複利用性。 將硝酸鉛、鋅、鎳、銅、鈷與鐵離子及錯離子水溶液配製奈米鑽石混合懸浮液。本實驗利用共扼焦顯微鏡了解奈米鑽石之生物共生與吸附特性。於重金屬吸附上運用LM324系統、及ICP-MS測量溶液濃度, 且用SEM觀察表面。 研究結果顯示,奈米鑽石具優越吸附離子能力,吸附前後奈米鑽石表面在巨觀與表面微觀上有顯著改變;且再利用性極佳,可利用硝酸置換出金屬離子。故奈米鑽石應可作為具再利用性之吸附材料。

Improving Particle Classification In Wimp Dark Matter Detection Using Neural Networks

In all experiments for detection of WIMP dark matter, it is essential to develop a classifier that can distinguish potential WIMP events from background radiation. Most often, clas- sifiers are developed manually, via physical modeling and empirical optimization. This is problematic for two reasons: it takes a great deal of time and effort away from developing the experiment, and the resulting classifiers often perform suboptimally (which means that a greater amount of expensive run time is required to obtain a confident experimental result). Machine learning has the potential to automate this and accelerate experimentation, and also to detect patterns that humans cannot. However, two major challenges, which are shared among several dark matter experiments, stand in the way: impure calibration data, which hinders training of models, and unpredictable physical dynamics within the detector itself. My objective was to develop a set of machine learning techniques that address these two problems, and thus more efficiently generate highly accurate classifiers. I was able to obtain raw data for two dark matter experiments which exhibit these challenges: the PICO-60 bubble chamber [2], and the DEAP-3600 liquid argon scintillator [1]. For each experiment, I developed and compared three general-purpose algorithms intended to resolve its inherent challenge (impurity and unpredictable dynamics, respectively). In PICO-60, background alpha and WIMP-like neutron calibration datasets are used for training; however, there is an impurity of 10% alphas in the neutron set. While a conventional classifier was developed (and is believed to be 100% accurate), machine learning in the form of a supervised neural network (NN) has also been previously explored, because of the benefits of automation. Unfortunately, it achieved a mean accuracy of only 80.2% – not usable as a practical replacement for conventional methods in future iterations of the experiment. In DEAP-3600, photons are absorbed by a wavelength shifting medium and re-emitted in an unpredictable direction, before being detected by one of 255 photomultiplier tubes (PMTs) around the spherical detector. The randomness severely limits the accuracy of conventional classifiers; in a simulation, the best so far removes 99.6% of alpha background, while also (undesirably) removing 91.0% of WIMP events. Because of physical limitations, simulated data is used for calibration, with 30 real-world experimental events available for testing. I have written a research paper [11] about my work on PICO-60, which has been approved by the PICO collaboration and pre-published at https://arxiv.org/abs/1811.11308. It is currently undergoing peer review for publication in Computer Physics Communications. All PICO researchers are listed on my paper for their work on the original PICO-60 experi- ment. They did not contribute to this study; I completed and documented it independently.

洞穴十字路-揭開東帝汶約萬年前的氣候秘辛

以東帝汶Monkey cave的MC2石筍進行鑽孔,拋光,得到各段的石筍粉末後,以鈾釷定年法得知生成年代,並得出石筍δ18O數值。 東帝汶Monkey cave的MC2石筍有81個鑽孔點,δ18O值介於-4.237 ‰~-2.452 ‰之間,δ18O氧同位素的變動範圍約在1.8 ‰之間。 MC2石筍生長時期13542~10740年前,即更新世晚期。 東帝汶MC2石筍在早期δ18O較晚期數值較重,而到後期較接近10740年前則是δ18O有一直變輕的趨勢,由此可看出早期雨量較晚期為少,且雨量呈現增加的趨勢,代表溫度上升,上升氣流較強,雨量較多所致。 東帝汶MC2石筍和約萬年前中國南京葫蘆洞石筍的δ18O值比較,呈現相反的趨勢,與新仙女木事件發生時(12800~11500年前),大西洋北部大量融冰注入,而造成暖流無法北上,造成低緯度溫度較高,雨量較多的有關。