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We design a three mode elliptical-core mode-selective photonic lantern (EC-MSPL) which can match well with the elliptical core few mode fiber in MIMO-free MDM systems. The mode crosstalk of the EC-MSPL are below −20dB for all three modes.
van der Waals (vdW) heterostructures enabled by two-dimensional (2D) semimetals and semiconductors [1] have shown interesting attractions and great promises toward realizing future-generation high performance electronic and optoelectronic devices. In this study, we demonstrate gallium selenide (GaSe) (p-type) /molybdenum disulfide (MoS2) (n-type) heterojunction. This heterojunction shows p-n junction...
We report on measuring radiation effects of energetic oxygen ions on silicon carbide (SiC) diaphragm resonators. Micromachined SiC diaphragms (1 mm × 1 mm × 2μm) vibrating at ∼200–800 kHz on multimode resonances are exposed to 14.3 MeV oxygen ions to sensitively probe the radiation effects of high-energy ions. We have observed frequency redshifts as large as ∼2.6%, as well as quality (Q) factor degradation...
We report on the design and demonstration of a self-powering sensor microsystem that exploits vibrational energy harvesting to fully supply power for an integrated, ultra-low-power, CMOS temperature sensor. This system features a novel circuit interface, capable of handling input harvested power down to the sub-μW level, enabled by an application-specific integrated circuit (ASIC) that performs energy...
To date, dynamic vehicle routing problem (DVRP) has attracted great research attentions due to its wide range of real world applications. In contrast to traditional static vehicle routing problem, the whole routing information in DVRP is usually unknown and obtained dynamically during the routing execution process. To solve DVRP, many heuristic and metaheuristic methods have been proposed in the literature...
Recently, the notion of Multifactorial Optimization (MFO) has emerged as a promising approach for evolutionary multi-tasking by automatically exploiting the latent synergies between optimization problems, simply through solving them together in an unified representation space [1]. It aims to improve convergence characteristics across multiple optimization problems at once by seamlessly transferring...
We report on the circuit design and experimental demonstration of a battery-less, self-powering temperature sensor node, powered entirely by a piezoelectric (PZE) ambient vibrational energy harvester, and enabled by a novel ultra-low-power application-specific integrated circuit (ASIC). The ASIC collects and stores energy generated by the PZE transducer into a supercapacitor, powers both the on-ASIC...
We present an ultra-low quiescent current power management integrated circuit (IC) for interfacing with a piezoelectric (PZE) energy harvester in a self-powering wireless sensor node. The PZE harvester first transforms mechanical energy from vibration into electricity. The AC output from the PZE is then converted into DC power using a full bridge rectifier, and charges a small filter capacitor. The...
This study aims at providing guidelines for designing electrostatically-actuated micro/nanoelectromechanical relays with a broad operating margin around the supply voltage VDD. Whereas it is tempting to focus mainly on minimizing the first pull-in voltage (Vpi) in order to enable a low VDD, special attention should be paid to the so-called catastrophic pull-in (Vcpi), which corresponds to the movable...
The increasing age of infrastructure such as bridges or tall buildings requires a significant effort to be performed with respect to inspection such that damage being considered critical can be recognized early in advance and a respective infrastructure management can be performed. Many countries take the advantage of advance in Unmanned Aerial Vehicle technologies and applied for mostly aerial mapping...
We describe a systematic study on quantifying the effects of heterostructure layer stacking upon measured dissipation and quality factors (Qs) of AlN-on-Si coupled-ring breathing mode micromechanical resonators. For the first time, we design and fabricate resonators of the same lateral dimensions but with different stacking layers, namely, Si, AlN-on-Si, and Al-on-AlN-on-Si. With both optical and...
This digest paper reports on the first demonstration of suspended β-Ga2O3 nanostructures and nanomechanical resonators made from single-crystal β-Ga2O3 nanosheets or nanomembranes grown via low pressure chemical vapor deposition (LPCVD) on 3C-SiC epi-layer on Si substrate. These single-crystal β-Ga2O3 drumhead nanomechanical resonators offer robust multimode resonances at frequencies in the range...
This paper reports the first experimental exploration of non-invasive and fast manipulation of breast cancer cells by harnessing multimode micromechanical resonators operating in biosolution. We demonstrate, for the first time, that groups of breast cancer cells are spatially manipulated into controlled microscale patterns, facilitated by the spatially abundant and diverse multimode resonances of...
We report on the first demonstration of electrothermally tunable graphene nanoelectromechanical resonators via Joule heating. We fabricate single-, bi- and tri-layer graphene resonators (up to 136MHz) to study electrothermal effects on resonance characteristics. The tri-layer graphene resonator exhibits frequency upshift from 9.5MHz to 26.1MHz by electrothermal heating, resulting in tuning range up...
We report on the first single- and few-layer molybdenum disulfide (MoS2) nanoelectromechanical resonators with local electrical gate, and the demonstration of local-gate all-electrical actuation, detection, and tuning of the atomic-layer MoS2 resonators at very high frequency (VHF). These local-gate structures make MoS2 vibrating-channel transistors (VCTs), and facilitate efficient frequency modulation...
The prediction of reliability for rubber O-rings used in the rockets is of great significance for the life assessment of the rockets. In this paper, rubber O-rings were aged under accelerated conditions at temperatures ranging from 60°C to 80°C. And a new model based on Wiener process with a time scale transformation was presented to describe the degradation of CS (compression set) which is the characteristic...
In order to build and then operate a new major dam and power station at Jinping, Sichuan Province, China, it was necessary to first construct an access road though mountainous terrain along the Yalong River. At one point this needed a 52.5 m high, soil-filled structure to support the road. Because of the proximity of the river a conventional slope could not be constructed. Various alternatives were...
Over the years, the algorithms of evolutionary computation have emerged as popular tools for tackling complex real-world optimization problems. A common feature among these algorithms is that they focus on efficiently solving a single problem at a time. Despite the availability of a population of individuals navigating the search space, and the implicit parallelism of their collective behavior, seldom...
MEMS resonators integrated with CMOS feedback networks have a potentially wide field of applications as oscillator circuits in communications and sensor systems. However, considerable advancements to this nascent technology are required to realize such a vision. We present a configurable CMOS chip which facilitates the development of MEMS-referenced oscillators, especially for timing and sensing applications...
We report on characterization of microsale lead zirconate titanate (PZT) thin film cantilevers, by both optical and electrical measurements, for up to the 7th resonance mode in 2kHz to 2MHz frequency range, with quality (Q) factors between 380 and 600. We also calibrate the PZT thin film's inverse piezoelectric coefficient (e31 ≈ −5C/m2). This work presents a multiphysical characterization of important...
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