Research Interests

超材料，波動力學，聲學，應用電磁學，天線，射頻微機電 

Metamaterials, Wave propagations, sound waves, applied electromagnetics, antennas, RF-MEMS

實驗室的訓練包含，理論分析、有限元素模擬、電路模擬、實驗量測分析，文獻探討與發想新的想法

本人的研究主要為以下

1. 新穎材料(meta-material)

https://scitechvista.nat.gov.tw/c/sTVn.htm?fbclid=IwAR2HBnOYf-9LWcQRXaGcoaEUpm0uY1IM4vpHuAVHw8rlIK0rHJoaQPSui9k

機械式可調變頻率選擇表面: 設計3種不同機構，包含超彈性可拉伸式、可旋轉式與連動桿式，連接所有的單元，透過單一驅動桿件，可同時調整每個單元，進而改變整體結構之頻率特性，與傳統電子式調變技術相比，機構式調變僅利用單一驅動桿件，就可達到大面積的調變，且不需要額外的驅動電路，可大幅減少所需要的被動電路元件。

2. 壓電超晶格天線

根據壓電超晶格所引發的晶格機械振動能夠使電磁波在遠小於波長的尺寸下，藉由極子在頻帶間隙最大化輻射效果，學理上，首先提出壓電超晶格具備天線之功能，其尺寸遠小於一般天線，未來可廣泛應用於國防科技與低頻通訊系統。

3. 電磁頻率選擇表面

研究電磁波穿隧效應現象與應用在設計高功率微波頻率選擇表面，於2018年幫中科院設計頻率選擇表面，可抵抗高達25 kW入射波能量，且無空氣電漿解離發生。

4. 心臟支架微型天線

基於心臟血管支架的體內無線傳感系統，包括心臟血管支架，安裝在所述心臟血管支架上的射頻收發機電路模塊以及壓力傳感器，所述心臟血管支架在作為血管支架的同時還作為系統的天線，實現與外部的能量和信息相互作用，以所臟血管支架作為天線延長發送無線信號，所述射頻收發機電路模塊還接收由所述心臟血管支架收到的外部信號，對所述外部信號進行解譯。可以實現實時的血壓監測，有利於患者和醫療人員快速及時地了解血壓狀態。 

5. 生醫應用與仿生設計(-2019已結束)

• 骨導式人工電子耳

• 壓阻式血流偵測系統

• 昆蟲仿生聲波測向系統

6. 介電彈性致動器(-2019已結束)

設計仿蝴蝶口器之軟性螺旋致動器: 透過電場驅動高介電液體，使致動器捲曲與展開，達到線性運動，可解決介電彈性體容易產生介電崩潰，由於整體為軟性設計，可應用於穿戴式裝置與輔具。

7. 應用機器學習演算法與深度學習於工具機顫振分析與抑制(-2019已結束)

利用不同機器學習方法，包含OCSVM與LOF，應用於CNC铣削加工機之顫振即時監測與抑制，並透過工研院智慧製造中心之CNC加工機驗證，目前並將此方法應用於北科大智慧製造中心之機台與台大智慧製造團隊之機台。

Honors and Rewards

• Student paper contest honorable mention (among 149 papers), 2014 IEEE International Symposium on Antennas and Propagation and USNC/URSI National Radio Science meeting, Memphis, TN, USA, 2014.

• 2013 Scholarship of the Phi Tau Phi Scholastic Honor Society, Mid-America Chapter.

• Invited 30-mins Oral Presentations, 2013 IEEE Power and Plasma Science Conference, Section: Microwave\RF Plasma Interactions, 2013.

• Best Student paper Award, 2013 IEEE Pulsed Power and Plasma Science Conference, San Francisco, California, 2013.

• Best Student paper finalist (among 152 papers), 2012 IEEE International Symposium on Antennas and Propagation and USNC/URSI National Radio Science meeting, Chicago, IL, USA, 2012.

• 2012 National Radio Science Meeting Travel Fellowship Award.

• Presidential Award (top 5% in the department), National Taiwan University, 2002.

• 指導碩士生陳奕達參加2016 IEEE 5th Asia-Pacific Conference on Antennas and Propagation (APCAP)的學生論文比賽，獲得最佳論文獎。

 學生獲獎:

(1)  指導碩士生陳奕達參加2016 IEEE 5th Asia-Pacific Conference on Antennas and Propagation (APCAP)的學生論文比賽，獲得最佳論文獎。

(2)  指導大學生胡翔與鄭丞予參加106年度工程論文競賽，分別獲得特優獎與佳作獎

(3)  指導碩士生洪鈺傑獲得中國機械工程學會106年度碩士論文獎佳作。

(4)  指導碩士生黃胤禎參加2017 International Conference on Mechatronic, Automobile, and Environment Engineering研討會，獲得最佳論文獎。

(5)  指導碩士生陳奕達與洪鈺傑獲得斐陶斐學會獎學金。

(6)  指導碩士生洪鈺傑獲得中國機械工程學會106年度碩士論文獎佳作。

(7)  指導碩士生陳星宇獲得中國機械工程學會第34屆全國學術研討會口頭報告競賽，榮獲盈錫精密工業股份有限公司特別獎。

(8)  指導碩士生陳星宇獲得中國機械工程學會107年度碩士論文獎第三名。

(9)  指導學生陳宇軒2018第四屆旭泰科技論文獎特別獎。

(10)盧永珊與張博智獲得first place of outstanding poster presentation award at 2019 symposium on Engineering, Medicine, and Biology Applications (SEMBA).

SCI Journal papers- (sstudent or post-doc, *corresponding author)  

 1. W.S. AlGhamdi, A. Fakieh, H. Faber, Y.H Lin, W.Z Lin, P. Y. Lu, C.H. Liu, K.N. Salama, T.D. Anthopoulos (2022). Impact of layer thickness on the operating characteristics of In2O3/ZnO heterojunction thin-film transistors. Applied Physics Letter, 121, 233503. (IF: 3.97, SCI, 41/178, PHYSICS, APPLIED).

2. J.S. Chen, Y.T. Chung, C.Y. Wang, W.Y. Lo, C.H. Liu, C.H. Yu, I.L. Chang, T.R. Lin. (2022). Ultrathin arch-like labyrinthine acoustic metasurface for low-frequency sound absorption. Applied Acoustics, 202, 109142. (IF: 3.614, SCI, 8/40, ACOUSTICS).

3. Y.-H. Lin, Y. Han, A. Sharma, W.S. AlGhamdi, C.-H. Liu, T.-H. Chang, X.-W. Xiao, W.-Z. Lin, P.Y. Lu, A. Seitkhan, A.D. Mottram, P. Pattanasattayavong, H. Faber, M. Heeney, T.D. Anthopoulos (2022). A Tri-Channel Oxide Transistor Concept for the Rapid Detection of Biomolecules Including the SARS-CoV-2 Spike Protein. Advanced Materials, 34, 2104608. (IF: 30.849, SCI, 2/219, Chemistry, Multidisciplinary). 

4. S.-H. Wang, Y.-K. Huang, C.-Y. Chen, L.-Y. Tang, Y.-F. Tu, P.-C. Chang, C.-F. Lee, C.-H. Yang, C.-C. Hung, C.-H. Liu, M.-D. Ker, and C.-Y. Wu (2021). Design of a Bone-Guided Cochlear Implant Microsystem with Monopolar Biphasic Multiple Stimulation and Evoked Compound Action Potential Acquisition and Its In Vivo Verification. IEEE Journal of Solid State Circuits, 56(10), 3062-3076. (IF: 5.013, SCI, 45/319, Engineering, Electrical & Electronic).

5. C.-S. Yang, Y.-C. Chung, Y.-S. Cheng, Y.-C. Hsu, C.-F. Chen, N.-N. Huang, H.-C. Chen, C.-H. Liu, J.-C. Hsu, Y.F. Lin, and T.-R. Lin (2021). Electrically Tunable Plasmonic Biosensors Based onCavity-Coupled Structure With Graphene. IEEE Journal of Selected Topics in Quantum Electronics, 27(4), 4601208. (IF: 4.544, SCI, 12/97, Optics). MOST 109-2221-E-002-070-MY3.

6. C.C. Huang and C.H. Liu* (2019). A biomimetic miniaturized microphone array for sound direction finding applications based on a phase-enhanced electrical coupling network. Sensors, 19(16),3469. (SCI,15/61/Instrument&Instrimentation).

7. C.H. Liu*, S.C. Chen, H.M. Hsiao (2019, Aug). A Novel Single-Connector Stent Antenna for Intravascular Monitoring Applications. Sensors, 19(21);4616. (SCI, 15/61/Instrument&Instrimentation).

A1.    P.W. Lins and C.H. Liu*, “Bio-inspired soft proboscis actuator driven by dielectric elastomer fluid transducers,” Polymers, vol. 11, no. 1, p. 142, 2019.

A2.    Y.D. Chens and C.H. Liu*, “Unsymmetrical Finger-shape DGSs for developing a compact, high-order, harmonic-suppressed bandpass filter,” Progress in Electromagnetics Research-PIER C, accepted, 2019.

A3.    C.C. Huangs and C.H. Liu*, “A biomimetic miniaturized microphone array for sound direction finding applications based on a phase-enhanced electrical coupling network,” IEEE Sensors Journal, minor revision (2019).

A4.    X.H. Qians, Y.C. Wus, T.Y. Yangs, C.H. Chengs, H.C. Chus, W.H. Chengs, T.Y. Yens, T.H. Lins, Y.J. Lins, Y.C. Lees, J.H. Changs, S.T. Lins, S.H. Lis, T.C. Wus, C.C. Huang, C.F. Lee, C.H. Yang, C.C. Hung, T.S. Chi, C.H. Liu, M.D. Ker, and C.Y. Wu, “The analyses and verification of in-vivo animal tests on the CMOS bone-guided cochlear implant microsystem,” IEEE Transactions on Biomedical Engineering, accepted, 2019.

A5.    Y.C. Yaos, Y.H. Chens, C.H. Liu*, and W.P. Shih, “Real-time chatter detection and automatic suppression for intelligent spindles based on wavelet packet energy entropy and local outlier factor algorithm,” International Journal of Advanced Manufacturing Technology, accepted (2019).

A6.    C.H. Liu*, Y.C. Huangs, S.H. Lis, Y.A. Chens, W.Z. Wangs, J.S. Yu, and W.P. Shih, “Microelectromechanical system-based biocompatible artificial skin phantoms,” Micro Nano Letters, pp. 1-6, 2018.

A7.    C.H. Liu*, P.W. Lins, J.A. Chens, Y.T. Lees, and Y.M. Changs, “Exploiting stretchable metallic springs as compliant electrodes for cylindrical dielectric elastomer actuators (DEAs),” Micromachines, vol. 8, no, 11, p. 339, 2017.

A8.    H.Y. Mis, C.H. Liu, T.H. Changs, J.H. Seos, H.L. Zhangs, S. J. Chos, N. Behdad, Z.Q. Ma, C.H. Yaos, Z.Y. Cais, S.Q. Gongs, “Characterizations of biodegradable epoxy-coated cellulose nanofibrils (CNF) thin film for flexible microwave applications, ” Cellulose, vol. 23, no. 3, pp. 1989-1995, 2016.

A9.    B.J. Kupczyks, A.A.S. Garcias, X. Xiangs, C.H. Liu, J.E. Scharer, and J.H. Booske, “Observations of memory effects and reduced breakdown delay via penning gas mixtures in high-power microwave dielectric window discharges, ” IEEE Transactions on Plasma Science, vol. 42, no. 5, pp. 1255-1264, 2016.

A10. C.H. Liu*, P. Carrigans, B. J. Kupczyks, X. Xiangsv, N. Behdad, J.E. Scharer, and J.H. Booske, “Metamaterials for rapidly forming large-area distributed plasma discharges for high-power microwave applications, ” IEEE Transactions on Plasma Science, vol. 43, no. 12, pp. 4099-4109, 2015.

A11. C.H. Liu*, J. D. Nehers, J. H. Booske and N. Behdad, “Investigating the effective range of vacuum ultraviolet-mediated breakdown in high-power microwave metamaterials,” Journal of Applied Physics, vol. 116, no. 14, 2014.

A1.    C.H. Liu*, J. D. Nehers, J. H. Booske and N. Behdad, “Investigation the physics of simultaneous breakdown events in high-power-microwave (HPM) metamaterials with multiresonant unit cells and discrete nonlinear responses,” IEEE Transactions on Plasma Science, vol. 42, no. 5, 2014.

A2.    C.H. Liu* and N. Behdad, “Investigating the impact of microwave breakdown on the responses of high-power microwave metamaterials, ” IEEE Transactions on Plasma Science, vol. 41, no. 10, pp. 2992-3000, 2013.

A3.    T.A. Carstenss, M.L. Corradinis, J.P. Blanchards, C.H. Lius, M. Lis, N. Behdad, Z. Ma, “Thermoelectric powered wireless sensors for dry-cask storage, ” IEEE Transactions on Unclear Science, vol. 60, no. 2, pp. 1072-1079, 2013.

A4.    C.H. Liu and N. Behdad, “High-Power microwave filters and frequency selective surfaces exploiting electromagnetic wave tunneling through ɛ–negative layers, ” Journal of Applied Physics, vol. 113, p. 064909, 2013.

A5.    C.H. Liu and N. Behda, “Theoretical Examination of Electromagnetic Wave Tunneling Through Cascaded ɛ– and µ– Negative Metamaterial Slabs, ” Journal of ‘Progress in Electromagnetics Research-PIER, vol. 42, pp. 1-22, 2012.

A6.    C.H. Liu and N. Behdad, “Tunneling and filtering characteristics of cascaded ε-negative metamaterial layers sandwiched by double-positive layers, ” Journal of Applied Physics, vol. 111, p. 014906, 2012.

A.      EI Journal papers- (sstudent or post-doc, *corresponding author)

B1.     None 

C. International Conference papers-

C1.       Y.S. Lu, C.F. Lee, and C.H. Liu, “Developing Biocompatible Iridium Oxide Electrodes for Bone-Guided Extra-Cochlear Implant,” ICBE 2018 : 20th International Conference on Biomedical Engineering, Japan, 2018.

C2.       S.C. Chen, Z.Y. Zhang, and C.H. Liu, “Stent-Based Antennas for Smart Stent Applications,” 2018 International Symposium on Antennas and Propagation (ISAP 2018), Busan, South Korea, 2018.

C3.       P.W. Lin and C.H. Liu, “A Liquid-Metal-Embedded Stretchable Frequency Selective Surfaces for Wide-Band Tuning,” 2018 IEEE AP-S International Symposium on Antennas and Propagation and USNC/URSI National Radio Science Meeting, Boston, Massachusetts, USA.

C4.       C.C. Huang and C.H. Liu, “Biomimetic acoustic direction-finding system,” 13th International Symposium on Measurement Technology and Intelligent Instruments, Xi’an, China, 2017. 

C5.       C.H. Liu and Y.C. Hung, “Inductively reconfigurable periodic structures for synchronous and wideband tuning,” The 8th International Conference on Metamaterials, Photonic Crystals and Plasmonics, Incheon, Korea, 2017. 

C6.       Y.D. Chen and C.H. Liu, “Exploiting Linkage Mechanisms for Synchronously Tunable Dual-Band Frequency Selective Surfaces with Large Areas,” The 8th International Conference on Metamaterials, Photonic Crystals and Plasmonics, Incheon, Korea, 2017. 

C7.       Y.D. Chen and C.H. Liu, “Rotationally Tunable Frequency Selective Surfaces for Large Areas via Linkage Mechanisms,” 2017 IEEE International Symposium on Antennas and Propagation & USNC/URSI National Radio Science Meeting, UCSD, USA, 2017. 

Y.C. Hung and C.H. Liu, “Linkage Mechanical for Large-Area Reconfigurable Periodic 

C1.       Structures,” 2017 IEEE International Symposium on Antennas and Propagation & USNC/URSI National Radio Science Meeting, UCSD, USA, 2017.

C2.       C.H. Liu, “Mechanically tunable large-area periodic structures,” 1st Japan-Taiwan International Engineering Forum, TokyoTech, Japan, 2017.

C3.       X.H. Qian, Y.C. Wu, T.Y. Yang, C.H. Cheng, H.C. Chu, W.H. Cheng, T.Y. Yen, T.H. Lin, Y.J. Lin, Y.C. Lee, J.H. Chang, S.T. Lin, S.H. Li, T.C. Wu, C.C. Huang, C.F. Lee, C.H. Yang, C.C. Hung, T.S. Chi, C.H. Liu, M.D. Ker and C.Y. Wu, “A Bone-Guided Cochlear Implant CMOS Microsystem Preserving Acoustic Hearing,” 2017 Symposia on VLSI Technology and Circuits, Kyoto, Japan, 2017. 

C4.       C. H. Liu, Y.A. Chen, P.H. Huang, J.H. Yu, and Wen-Pin Shih, “Development of a galatin-based artificial skin phantom for electrical treatments,” 2nd Association of Computational Mechanics Taiwan Conference, Taipei, Taiwan, 2016.

C5.       Y.C. Hung and C.H. Liu, “Stretchable Frequency Selective Surfaces for Large-Area-Tuning and High-Power Applications,” International symposium on antennas and propagation, Japan, 2016.

C6.       Y.D. Chen and C.H. Liu, “Exploiting Hi-Lo Inter-Digital DGS for High-Order Microstrip Bandpass Filters,” 2016 IEEE 5th Asia-Pacific Conference on Antennas and Propagation (APCAP), 2016.

C7.        J.A. Chen, Y.T. Lee, Y.M. Chang, C.H. Liu, and W.P. Shih, “Stretchable Spring Electrodes for Cylindrical Dielectric Elastomer Actuators,” 2016 The 2nd International Conference on Control, Automation and Robotics, 2016 The 2nd International Conference on Control, Automation and Robotics, 2016. 

C8.       C.H. Liu, “Mechanically tunable large-area frequency selective surfaces,” 2nd NTU-UTokyo International Joint Conference, Taipei, Taiwan, 2016. 

C9.       (EI) C.H. Liu, K. Ghaemi, and N. Behdad, “A Small-Aperture, VHF Direction Finding System Exploiting Biomimetic Antenna Arrays,” 2015 IEEE AP-S/USNC-URSI conference, Vancouver, BC, Canada, 19-25 July 2015

C10.   (EI) C.H. Liu, J. H. Booske and N. Behdad, “Investigating Failure Mechanisms in High-Power Microwave Frequency Selective Surfaces,” 2014 IEEE AP-S/USNC-URSI conference, Memphis, Tennessee, 6-12 July 2014.

C11.   (EI) C.H. Liu, J. D. Neher, J. H. Booske and N. Behdad, “Investigating the Physics of Simultaneous Breakdown Events in Metamaterials with Multi-Resonant Unit Cells,” 15th IEEE International Vacuum Electronics Conference, Monterey, California, 22-24 April 2014. 

C12.   C.H. Liu, J. D. Neher, J. H. Booske and N. Behdad, “Investigating the Physics of Microwave Induced Breakdown in Metamaterials with Multi-Resonant Constituting Unit Cells,” American Physical Society (APS) - Division of Plasma Physics, Denver, Colorado USA, 11-15 Nov. 2013. 

C13.   (EI) C.H. Liu and N. Behdad, “Metamaterials with Discrete Nonlinear Response for High-Power Microwave Applications,” IEEE Pulsed Power & Plasma Science, San Francisco, California USA, 16-21 June 2013.

C14.   (EI) B. Kupczyk, C.H. Liu, X. Xiang, J. Scharer, N. Behdad, and J. Booske, “Redued breakdown delay in high power microwave dielectric window discharges,” IEEE Pulsed Power & Plasma Science, San Francisco, California USA, 16-21 June 2013.

C15.   (EI) C.H. Liu and N. Behdad, “Plasma-Tunable Metamaterials and Periodic Structures,” 14th IEEE International Vacuum Electronics Conference, Paris, France, 21-23 May 2013.

C16.   (EI) C.H. Liu and N. Behdad, “High-Power Microwave Filters and Frequency Selective Surfaces Utilizing EM Wave Tunneling Through ɛ-Negative Layers,” IEEE AP-S/USNC-URSI, Session IF37, Chicago, IL USA, 2012.

(EI) C.H. Liu and N. Behdad, “Analysis of Electromagnetic Wave Tunneling Through Stacked 

C1.       Single-Negative Metamaterial Slabs: a Microwave Filter Theory Approach,” IEEE AP-S/USNC-URSI, Session IF37, Chicago, IL USA, 2012.

C2.       C.H. Liu and N. Behdad, ‘Electromagnetic Wave Tunneling Through Multiple Epsilon-Negative Metamaterial Layers: A Microwave Filter Theory Approach,’ USNC-URSI National Radio Science Meeting, Boulder, Colorado, USA, 2012.

C3.       C.H. Liu and Y.-F. Chou, “Attenuation Coefficients Prediction for Reflection Layers of Solidly Mounted Resonators via Phononic Band Structures,” Proceedings of IMECE2008, ASME paper No. IMECE2008-67282, Oct. 31-Nov. 6, Boston, Massachusetts, USA, 2008.

D. Domestic Conference papers-

D1.        Y.S. Lu, P.C. Chang, C.F. Lee, P.C. Chen, and C.H. Liu, “A novel bone-guided stimulation method for extra-cochlear implants with vivo tests,” 2019 Symposium on Engineering, Medicine (SEMBA), and Biology Applications, Taoyuan, Taiwan, 2019.

D2.         P.W. Lin and C.H. Liu, “Bio-inspired soft proboscis actuator driven by dielectric elastomer fluid transducers,” 2019 Symposium on Engineering, Medicine (SEMBA), and Biology Applications, Taoyuan, Taiwan, 2019.

D3.        S.H. Li, C.C. Huang, and C.H. Liu, “Novel design of artificial electronic cochlear,” International symposium on Optomechatronic Technology, Tainan, Taiwan, 2017.

D4.        H.Y. Chen, W.P. Shih, and C.H. Liu, “Wearable real-time blood-flow condition monitoring system for CPR,” 34th National Conference on Mechanical Engineering of CSME, Taichung, Taiwan, 2017.

D5.        黃建璋與劉建豪, “Bandwidth Enhancement for Acoustic Direction Finding Systems,” 中國機械工程學會第三十四屆全國學術研討會, 台中, 2017, 12月.

D6.                  謝明華、趙家倫與劉建豪, “與護膝整合之輔助軟性外骨骼,” 中國機械工程學會第三十四屆全國學術研討會, 台中, 2017, 12月.

D7.                  陳星宇、施文彬與劉建豪, “穿戴式即時血流狀態偵測系統用於CPR急救,” 中國機械工程學會第三十四屆全國學術研討會, 台中, 2017, 12月.

D8.                  劉建豪與周元昉, “Effect of film thickness deviation on the performance of solidly mounted resonators,” 第十三屆奈米工程暨微系統技術研討會, 國立交通大學, 新竹, 2009年7月.

Lab equipment