智能牙刷可以藉由監測刷牙方式來維持牙齒的健康，正確的刷牙位置的監測非常重要。本論文提出了一個改善刷牙位置辨識的方法。首先運用中值濾波降低感測器雜訊，並且抑制不規則的高頻刷牙運動，減少偵測的角度突波，以便得到更精確的運動特徵，接著我們使用機率神經網路(Probabilistic Neural Network, PNN)分類方法，來進行刷牙區域辨識。依據實驗結果，相對於現有k-means的刷牙區域分類方法，PNN分類方法能獲得更佳的區域分類性能，讓使用者能夠更準確監測正確刷牙狀態。此一成果可以結合智能手機作為閘道器連結雲端，藉收集即時刷牙資料，發展遠端牙齒健康照護和疾病預防的應用。

Smart toothbrushes can be designed to monitor tooth brushing procedures to facilitate the maintenance of dental health. This necessitates a monitoring mechanism that identifies proper tooth brushing regions. In this study, an improved technique for identifying tooth brushing regions was proposed. First, a median filter was used to attenuate sensor noise and control irregular high-frequency tooth brushing motions, thereby reducing angular surges during detection and obtaining as precise of tooth brushing motion characteristics as possible. Then, a probabilistic neural network (PNN) was applied to identify tooth brushing regions. The experimental results showed that, compared with the conventional k-means algorithm, the PNN was more effective at classifying tooth brushing regions to enable users to monitor their tooth brushing more precisely. The proposed technique can be integrated through smartphone gateways to cloud services to collect real-time tooth brushing data for application in the development of remote dental healthcare and dental disease prevention services.

參考文獻
[1] Akiyoshi W. (2007, August). PNN Algorithm for PC Grid System, International Conference on Software Engineering Advances, Conference conducted at Cap Esterel, French Riviera, France.
[2] Anthony Z. (1998). Introduction to the Modified Probabilistic Neural Network for General Signal Processing Applications. IEEE transaction on signal processing, 46(7), 1980-1990.
[3] Ching-Han, C., Tun-Kai, Y., Jia-Hong, D., & Chen-Yuan, C. (2014). A pipelined multiprocessor SOC design methodology for streaming signal processing. Journal of Vibration and Control, 20, 163-178.
[4] Ching-Han, C., Chia-Ming, K., Chen-Yuan, C., & Jia-Hong, D. (2013). The design and synthesis using hierarchical robotic discrete-event modeling. Journal of Vibration and Control, 19, 1603-1613.
[5] Fairfield, D.H., & Ness N.F. (1970). Configuration of the geomagnetic tail during substorms. Journal of Geophysical Research, 75, 7032-7047.
[6] Gatzemeyer J., Jimenez E., Biron G., Delz M., Hopkins T., Read R., & Hohlbein D. (2012). INTERACTIVE TOOTHBRUSH. TW Patent No. I373328B1.
[7] Grush. (2016). Grush: The Gaming Toothbrush. Retrieved from http://www.grushgamer.com
[8] InvenSense. (2014). MPU-9255 Product Specification. Doc ID DS-000007 Rev 1.
[9] Kemp J.H. (2013). TOOTHBRUSH HAVING A REACTION AND DELIVERY SYSTEM AND BRUSH, TW Patent No. I387441B1.
[10] Kolibree. (2015). Rabbids Invasion on Kolibee! Retrieved from http://www.kolibree.com/en/
[11] MacQueen, J.B. (1967). Some methods for classification and analysis of multivariate observations. In Proceedings of the Fifth Berkeley Symposium on Mathematical Statistics and Probability (Lucien M.L., & Jerzy N. Ed., 5th ed., pp. 281–297). (Proc. Fifth Berkeley Symp. on Math. Statist. and Prob., Vol. 1). Berkeley, CA: University of California Press.
[12] Mayer, R.J. (1992). IDEF0 Function Modeling. Air force Systems Command.
[13] Oral-B. (2016). Black 7000 Electric Rechargeable Bluetooth Toothbrush. Retrieved from http://oralb.com/en-us/products/7000-wireless-smartguide-plus-electric-toothbrush
[14] Philips. (2016). Philips Sonicare Electirc Toothbrushes. Retrieved from http://www.usa.philips.com/c-m-pe/electric-toothbrushes
[15] STMicroelectronics. (2010). Using LSM303DLH for a tilt compensated electronic compass. Application note (AN3192). Doc ID 17353 Rev 1.
[16] STMicroelectronics. (2016). ARM Cortex-M4 32b MCU+FPU, 225DMIPS, up to 2MB Flash/256+4KB RAM, USB OTG HS/FS, Ethernet, 17 TIMs, 3 ADCs ,20 comm. Interfaces, camera & LCD-TFT. STM32F429xx. Doc ID 024030 Rev 8.
[17] STMicroelectronics. (2016). Discovery kit with STM32F429ZI MCU. User manual (UM1670). Doc ID 25175 Rev 2.
[18] Tom F. (2006). An introduction to ROC analysis. Pattern Recognition Letters, 27, 861-874.
[19] Wikimedia. (2011). File:Curvas.png. Retrieved from https://commons.wikimedia.org/wiki/File:Curvas.png
[20] Wikipedia. (2016). Median Filter. Retrieved from https://en.wikipedia.org/wiki/Median_filter
[21] Wikipedia. (2016). Receiver operating characteristic. Retrieved from https://en.wikipedia.org/wiki/Receiver_operating_characteristic
[22] Young, J.L., Pil, J.L., Kyeong, S.K., Wonse, P., Kee, D.K., Dosik, H., & Jeong, W.L. (2012). Toothbrushing Region Detection Using Three-Axis Accelerometer and Magnetic Sensor. IEEE Transactions on Biomedical Engineering, 59(3), 872-881.
[23] 石鈷、陳光明、石志鵬、李蓮芳和葉三顯(2012)。具互動功能之音樂牙刷。中華民國發明專利第M432326U1號。
[24] 周鴻源(2015)。智能牙刷套。中華民國發明專利第M512961U號。
[25] 許永和、蔡詩禮和吳孟錩(2012)。音波牙刷及刷牙時產生音樂的方法。中華民國發明專利第I367084B1號。
[26] 許永和和吳孟錩(2014)。勢矯正牙刷。中華民國發明專利第M479660U號。
[27] 許永和、蔡詩禮和吳孟錩(2015)。具有姿勢矯正裝置之牙刷。中華民國發明專利第M509575U號。
[28] 楊郁莉(2012) 。九軸運動感測器融合及應用（未出版之碩士論文）。國立中央大學軟體工程研究所，桃園市。
[29] 維基百科(2016)。陀螺儀。檢自：https://zh.wikipedia.org/wiki/陀螺儀