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Resonant magnetoelastic microstructures for wireless actuation of liquid flow on 3D surfaces and use in glaucoma drainage implants

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Microsystems & Nanoengineering 2015年第1期1卷 26-34页

作者： Venkatram Pepakayala Joshua Stein Yogesh Gianchandani center for wireless integrated microsensing and systems(WIMS2) Department of Electrical Engineering and Computer ScienceUniversity of MichiganAnn ArborMIUSA Department of Ophthalmology and Visual Sciences University of MichiganAnn ArborMIUSA

Magnetoelastic resonators made from metal alloy foils are widely used for miniature wireless anti-theft tags and have also been explored for use in various sensing *** annealing within three-dimensional(3D)molds,these foils can be formed into curved ***,magnetoelastic materials present an opportunity for the development of a new class of wireless,actuators that have small form factors and low surface profiles and that can conform to curved *** paper describes passive,wireless,resonant magnetoelastic actuators intended for the generation of fluid flow on the surfaces of implantable Ahmed glaucoma drainage *** actuators are remotely excited to resonance using a magnetic field generated by external *** fluid flow is intended to limit cellular adhesion to the surface of the implant,as this adhesion can ultimately lead to implant encapsulation and *** actuators are micromachined from planar 29-μm-thick foils of Metglas 2826MB(Fe_(40)Ni_(38)Mo_(4)B_(18)),an amorphous magnetoelastic alloy,using photochemical *** 10.3×5.6 mm^(2),the planar structures are annealed in 3D molds to conform to the surface of the drainage device,which has an aspherical *** actuator designs are described,with varying shapes and resonant mode *** resonant frequencies for the different designs vary from 520 Hz to 4.7 *** velocities of up to 266μm s^(−1) are recorded at a wireless activation range of 25–30 mm,with peak actuator vibration amplitudes of 1.5μ*** actuators such as those described here have the potential to greatly enhance the effectiveness of glaucoma drainage devices at lowering eye pressure and may also be useful in other areas of medicine.

关键词： actuator fibrosis glaucoma magnetostriction Metglas

Portable comprehensive two-dimensional microgas chromatography using an integrated flowrestricted pneumatic modulator

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Microsystems & Nanoengineering 2022年第6期8卷 61-72页

作者： Xiaheng Huang Maxwell Wei-hao Li Wenzhe Zang Xiaolu Huang Anjali Devi Sivakumar Ruchi Sharma Xudong Fan Department of Biomedical Engineering University of MichiganAnn ArborMI 48109USA Department of Electrical Engineering and Computer Science University of MichiganAnn ArborMI 48109USA center for wireless integrated microsensing and systems(WIMS2) University of MichiganAnn ArborMI 48109USA Max Harry Weil Institute for Critical Care Research and InnovationUniversity of Michigan Ann ArborMI 48109USA

Two-dimensional(2D)gas chromatography(GC)provides enhanced vapor separation capabilities in contrast to conventional one-dimensional GC and is useful for the analysis of highly complex chemical *** developed a microfabricated flow-restricted pneumatic modulator(FRPM)for portable comprehensive 2D micro-GC(μGC),which enables rapid ^(2)D injection and separation without compromising the ^(1)D separation speed and eluent peak profiles.^(2)D injection characteristics such as injection peak width and peak height were fully characterized by using flow-through micro-photoionization detectors(μPIDs)at the FRPM inlet and outlet.A ^(2)D injection peak width of~25 ms could be achieved with a ^(2)D/^(1)D flow rate ratio over *** FRPM was further integrated with a 0.5-m long ^(2)D μcolumn on the same chip,and its performance was ***,we developed an automated portable comprehensive 2D μGC consisting of a 10m OV-11D μcolumn,an integrated FRPM with a built-in 0.5m polyethylene glycol ^(2)D μcolumn,and two μ*** separation of 40 volatile organic compounds in~5 min was demonstrated.A hybrid 2D contour plot was constructed by using both ^(1)D and ^(2)D chromatograms obtained with the two μPIDs at the end of the ^(1)D and ^(2)D μcolumns,which was enabled by the presence of the flow resistor in the FRPM.

关键词： flow restricted comprehensive

A triple-band miniaturized end-fire antenna based on odd-mode spoof surface plasmonic polariton waveguide resonator

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Optoelectronics Letters 2025年

作者： BAI Yukun MAO Mengqun Tianjin Key Laboratory of Film Electronic and Communication Devices， Engineering Research center of Optoelectronic Devices and Communication Technology， Ministry of Education， School of integrated Circuit Science and Engineering， Tianjin University of Technology

A triple-band miniaturized end-fire antenna based on the odd modes of spoof surface plasmonic polariton (SSPP) waveguide resonator is proposed in this paper. To meet the ever increasing demand for more communication channels and less antenna sizes， multi-band antennas are currently under intensive investigation. By a novel feeding method， three odd modes are excited on an SSPP waveguide resonator， which performs as an end-fire antenna operating at three bands， 7.15-7.26GHz， 11.6-12.2GHz and 13.5-13.64GHz. It exhibits reasonably high and stable maximum gains of 5.26， 7.97 and 10.1dBi and maximum efficiencies of 64%， 92% and 98% at the three bands， respectively. Moreover， in the second band the main beam angle shows a frequency dependence with a total scanning angle of 19°. The miniaturized triple-band antenna has a great potential to be applied in wireless communication systems， satellite communication and radar systems.

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Transmit scheme to improve coverage in simulcast system based on wideband channel measurement in indoor at 6 GHz

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The Journal of China Universities of Posts and Telecommunications 2013年第2期20卷 48-53,72页

作者： XIN Liang ZHANG Jian-hua GAO Jun-jun LI Xiao-fan Chipset R&D-systems Engineering-systems Design VIATelecom wireless Technology Innovation Institute Key Laboratory of Universal Wireless Communication Ministry of Education Beijing University of Posts and Telecommunications State Ratio-monitoring-center Testing center

Array gain would be well exploited to improve power coverage if some powerful multipath components from different radio links can coherently combine at the receiver （Rx）. Thus, in this paper, an algorithm is proposed for transmission in simulcast system, where partial channel state information （CSI） is needed. Based on measured multipath channel, performance of the proposed algorithm is evaluated. According to simulation results, the proposed algorithm outperforms the direction summation （DS） scheme and multipath antenna diversity （MAD） algorithm, with 2～4 dB advantage over the latters. Especially in line of sight （LOS） scenario, the advantage is more obvious. Besides, the proposed algorithm brings more gain with increasing number of transmit antennas without additional power. Finally, robustness of the proposed algorithm is examined with imperfect CSI.

关键词： channel measurement delay difference phase rotation coverage robustness

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Terahertz dual-beam leaky-wave antenna based on multi-mode spoof surface plasmon polariton waveguide

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Optoelectronics Letters 2025年

作者： BAI Yukun HAN Yuanqing Tianjin Key Laboratory of Film Electronic and Communication Devices， Engineering Research center of Optoelectronic Devices and Communication Technology， Ministry of Education， School of integrated Circuit Science and Engineering， Tianjin University of Technology

In this paper， a terahertz dual-beam leaky-wave antenna (LWA) based on a multi-mode spoof surface plasmon polariton (SSPP) waveguide is proposed. By dispersion engineering of the SSPP transmission line (SSPP TL)， multiple modes are excited on the SSPP TL. A dual-beam LWA is constructed based on the radiation from the first space harmonics of the guided fundamental mode and the first higher-order mode. The simulation results show that the antenna radiates frequency-dependent dual beams in the 1.9 ～ 2.6 THz operating frequency band. The average gains for the two beams are 12.9 dBi and 8.2 dBi， respectively. The compact dual-beam LWA is promising in the application of wireless communication and radar systems.

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Compact wideband filtering antenna based on SIW resonator

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Optoelectronics Letters 2025年

作者： LIU Shaoshuai BAI Yukun Tianjin Key Laboratory of Film Electronic and Communication Devices， Engineering Research center of Optoelectronic Devices and Communication Technology， Ministry of Education， School of integrated Circuit Science and Engineering， Tianjin University of Technology

This paper proposes a novel wideband filtering antenna based on a double-mode substrate integrated waveguide (SIW) resonator. By etching butterfly-shaped slots on the upper surface of the SIW resonator， mixed modes based on TE110 and TE120 are introduced， which enhances the antenna's bandwidth. Additionally， the incorporation of a defected ground structure (DGS) suppresses out-of-band radiation and improves the overall filtering performance of the antenna. The final design achieves a center frequency of 2.41 GHz with an impedance bandwidth of 11.71%. Compared to other filtering antennas， the proposed antenna features a compact size， wide bandwidth， excellent filtering performance， and ease of integration， meeting the high-integration and miniaturization requirements in wireless communication systems.

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Compact prototype microfabricated gas chromatographic analyzer for autonomous determinations of VOC mixtures at typical workplace concentrations

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Microsystems & Nanoengineering 2018年第1期4卷 390-399页

作者： Junqi Wang Jonathan Bryant-Genevier Nicolas Nuñovero Chengyi Zhang Bruce Kraay Changhua Zhan Kee Scholten Robert Nidetz Sanketh Buggaveeti Edward T.Zellers Department of Chemistry University of MichiganAnn ArborMI 48109USA Department of Environmental Health Sciences University of MichiganAnn ArborMI 48109USA Applied Physics Program University of MichiganAnn ArborMI 48109USA Department of Mechanical Engineering University of MichiganAnn ArborMI 48109USA center for wireless integrated microsensing and systems University of MichiganAnn ArborMI 48109USA

This report concerns a benchtop prototype instrument containing a gas chromatographic microanalytical system(μGC)designed for the selective determination of multiple airborne volatile organic compounds(VOCs)at concentrations in the vicinity of recommended occupational exposure *** core microsystem consists of a set of discrete Si-microfabricated devices:a dualcavity,adsorbent-packed micro-preconcentrator-focuser(μPCF)chip that quantitatively captures and thermally desorbs/injects VOCs with vapor pressures between~0.03 and 13 kPa;tandem micro-column(μcolumn)chips with cross-linked PDMS wall-coated stationary phases capable of temperature-programmed separations;and an integrated array of fiveμchemiresistors(μCR)coated with different thiolate-monolayer protected gold nanoparticle(MPN)interface films that quantifies and further differentiates among the analytes by virtue of the response patterns *** key components include a pre-trap for low-volatility interferences,a split-flow injection valve,and an onboard He carrier–gas *** assembled unit measures 19×30×14 cm,weighs~3.5 kg,operates on AC power,and is laptop/LabVIEW ***-and system-level tests of performance demonstrated injection bandwidths o1 s,aμcolumn capacity of≥8μg injected mass,linear calibration curves,no humidity effects,excellent medium-term(that is,1 week)reproducibility,autonomous operation for 8 h,detection limits below Threshold Limit Values(TLV)for 10 mL air samples collected in 1 min,and response patterns that enhanced vapor *** determination of a 17-VOC mixture in the presence of seven interferences was performed in 4 *** augur well for adapting the microsystem to an all-MEMS wearableμGC currently under parallel development.

关键词： gas chromatography micro-GC microsystem mixtures sensor array VOCs

Interference Robust Channel Hopping Strategies for wireless Sensor Networks

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China Communications 2016年第3期13卷 96-104页

作者： LIU Ye JIANG Fulong LIU Hao WU Jianhui HU Chen ZHANG Meng National ASIC System Engineering Research center Southeast University Suzhou Key Laboratory of integrated Circuits and systems Southeast University

Due to the shared nature of the wireless medium, the performance of wireless sensor network is often limited by both internal interference and external interference. The internal interference is that simultaneous traffic activity by neighboring nodes in the same network, while the external interference is from wireless transmissions by other types of devices, such as Wi-Fi and Bluetooth nodes. In this paper, we present two channel hopping algorithms for multichannel, single-radio wireless sensor networks. The first algorithm achieves collision-free transmission environment while do not introduce extra control overhead. The second algorithm, in addition to reducing internal interference effects, reduces the external interference effects from Wi-Fi devices. Simulation results show that both of them significantly improve performance in wireless sensor network.

关键词： WSN channel assignment latin rectangular array interference

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Generalized analysis model for fractional frequency reuse

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The Journal of China Universities of Posts and Telecommunications 2010年第5期17卷 1-5页

作者： XI Wei YIN Chang-chuan YUE Guang-xin SUN Hong-mei Laboratory of wireless Cornmtmication systems and Networks Beijing University of Posts and Telecommunications Beijing 100876 China Communication Technology Laboratory Intel China Research Center Beijing 100190 China

Fractional frequency reuse （FFR） is an effective technique to mitigate co-channel interference in orthogonal frequency division multiple access （OFDMA）-based broadband cellular *** this paper,we present a generalized model for FFR under which all existing FFR schemes can be considered as its special ***,quality factor has been proposed to indicate the quality of the *** interesting conclusion can be drawn that,as the power ratio in FFR is adjusted continuously,the corresponding quality factor varies ***,simulation is conducted based on worldwide interoperability for microwave access （WiMAX）,and the result agrees well with our theoretical ***,an effective range for power ratio is presented,which is very instructive to practical system design.

关键词： co-channel interference FFR power ratio

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