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With the increase in elevator usage, more and more elevator real-time monitoring equipment is being applied to the operation of elevators. Traditional elevator monitoring equipment adopts a multi-sensor decentralized installation and layout, and the monitoring accuracy is low, which directly affects the effective alarm of the monitoring system; however, existing online monitoring systems cannot quickly alarm for faults. Aiming to solve the above problems, an elevator online monitoring system based on narrow-band Internet of Things (NB-IoT) is designed. The system is highly integrated with an STM32 main control chip, a six-axis acceleration gyroscope sensor, and an air pressure sensor to realize the edge calculation of the monitoring system. At the same time, this paper eliminates the temperature drift of the pressure sensor by using a temperature compensation algorithm and inputs the extracted characteristic parameters into the BP neural network for training to eliminate the zero drift so as to obtain the real-time height data of the elevator. The six-axis acceleration gyroscope sensor is used to calculate the posture so as to avoid the problem that a three-axis acceleration sensor or a three-axis gyroscope sensor alone cannot obtain accurate posture data. In order to further improve the monitoring accuracy, the peak-to-peak value of the signal is calculated by using a 95% confidence interval algorithm to reduce the suppression of the high-frequency components of the signal by noise and ensure that the signal has a large signal-to-noise ratio so that the obtained elevator car posture and vibration operation data are more accurate. Finally, the effectiveness of the proposed method is verified by experiments. [ABSTRACT FROM AUTHOR]

Copyright of Machine Tool & Hydraulics is the property of Guangzhou Mechanical Engineering Research Institute (GMERI) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

With the increase in elevator usage, more and more elevator real-time monitoring equipment is being applied to the operation of elevators. Traditional elevator monitoring equipment adopts a multi-sensor decentralized installation and layout, and the monitoring accuracy is low, which directly affects the effective alarm of the monitoring system; however, existing online monitoring systems cannot quickly alarm for faults. Aiming to solve the above problems, an elevator online monitoring system based on narrow-band Internet of Things (NB-IoT) is designed. The system is highly integrated with an STM32 main control chip, a six-axis acceleration gyroscope sensor, and an air pressure sensor to realize the edge calculation of the monitoring system. At the same time, this paper eliminates the temperature drift of the pressure sensor by using a temperature compensation algorithm and inputs the extracted characteristic parameters into the BP neural network for training to eliminate the zero drift so as to obtain the real-time height data of the elevator. The six-axis acceleration gyroscope sensor is used to calculate the posture so as to avoid the problem that a three-axis acceleration sensor or a three-axis gyroscope sensor alone cannot obtain accurate posture data. In order to further improve the monitoring accuracy, the peak-to-peak value of the signal is calculated by using a 95% confidence interval algorithm to reduce the suppression of the high-frequency components of the signal by noise and ensure that the signal has a large signal-to-noise ratio so that the obtained elevator car posture and vibration operation data are more accurate. Finally, the effectiveness of the proposed method is verified by experiments.

In this work, the surface of long-period fiber grating (LPFG) and polarization maintaining fiber (PMF) is functionalized based on the interaction between the resonance wavelength and external environment. LPFG coated with a 150 nm ZnSe/Co film is fixed on a hollow bracket, prestressed, and annealed many times. A highly sensitive liquid level sensor with adjustable sensitivity, an adjustable measurement range, and a high liquid level early warning is prepared. The waveguide layer controlled by humidity is constructed by filling poly-(3,4-ethylenedioxythiophene)/poly-(styrene sulfonate) (PEDOT/PSS) in a periodically etched PMF. The surface is coated with a poly-(vinyl alcohol) (PVA) and carbon nanotube (CNT) composite polymer. After laser processing, a honeycomb porous film is obtained, and the humidity sensor with wavelength modulation is prepared. The pH-sensitive polymer is successively adsorbed on the surface of PMF coated with a 120 nm indium tin oxide (ITO) film by electrostatic self-assembly (ESA). Poly-(allylamine hydrochloride) (PAH), poly-(acrylic acid) (PAA), and poly-(styrene sulfonate) (PSS) constitute a composite film with rapid deposition and high permeability that is covered with polyaniline/poly-(methyl methacrylate) (PMMA) as the protective layer. After laser processing, a fluffy porous film structure is formed. The pH sensor is obtained and the preparation steps are greatly reduced. Finally, based on the wavelength division multiplexing (WDM) and multiwavelength matrix (MWM), the problem of crosstalk is solved. An integrated sensor is constructed to realize the simultaneous measurement of temperature, liquid level, humidity, and pH. It has been successfully applied to monitor the overall environment of a chemical waste liquid storage tank. The sensor has the advantages of remote monitoring, safety, efficiency, and labor-saving. [ABSTRACT FROM AUTHOR]

Copyright of Journal Of Sichuan University (Natural Sciences Division) / Sichuan Daxue Xuebao-Ziran Kexueban is the property of Editorial Department of Journal of Sichuan University Natural Science Edition and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A highly-integrated frequency tunable filtering balun-diplexer (FBD) is introduced in this article. Firstly, the tunable coupled-line-loaded hairpin ring resonator (C-HRR) with two independently tunable resonant modes is analyzed. Then two tunable filtering baluns (FBs) for the two frequency tunable channels of the FBD are designed based on the tunable C-HRR. The constant fractional bandwidth (FBW) performance of two tunable FBs is discovered and discussed. Finally, a tunable FBD is designed by simply uniting the two tunable FBs and sharing the common input port and one C-HRR which reduces the circuit size effectively. The low loading effect ensures the two frequency channels of the FBD being tuned independently. For validation, a prototype of the tunable FDB is fabricated and measured. The lower and higher channels can achieve a constant 4 % FBW in a tuning range of 9 % and 14 %, respectively. The CM noise rejection is higher than 36 dB with in-band channel isolation greater than 35 dB. The circuit size is 0.27 λ g × 0.15 λ g , where λ g is guide wavelength at the highest operation frequency of the lower channel. [ABSTRACT FROM AUTHOR]

A compact wearable smart sensor for the application of wireless body sound monitoring is presented. It supports several kinds of body sound monitoring and has been measured with heart sound as an example. With the sensor, a wireless body sound monitoring system can be realized, which enables us to 'build a hospital in our pocket'. In order to achieve a small form factor, a dedicated highly integrated chipset has been designed for the wearable sensor. The chipset consists of a sensor readout chip for data acquisition and a 400 MHz band transceiver chip for wireless communication. It has been fabricated in CMOS technologies and can provide all the necessary sensor functions with a commercial EEPROM chip. Excluding the matching network, only eight off-chip components are required to fabricate the hardware system of the sensor, which helps to significantly improve integrated level. [ABSTRACT FROM AUTHOR]

Environmental stability is one of the most important parameters for high-performance organic field-effect transistors (OFETs). Hydrophobic insulators usually possess much better air stability than some conventional inorganic and hydrophilic organic insulators. However, fabrication of devices with high integration by photolithography method cannot be directly performed on hydrophobic insulators due to their photoresist-unwettable properties. In this work, a simple yet efficient metal-assisted photolithography method is developed to achieve large-scale fabrication of highly integrated organic electronic devices on photoresist-unwettable insulators. By using copper (Cu) as sacrificial layer, photolithography can be performed on these insulators with nearly the same resolution, uniformity, and reproducibility as the conventional photolithography. This method shows excellent flexibility and is capable of fabricating high-integrated devices on a variety of hydrophobic insulators including hydrophobic amorphous fluoropolymer (CYTOP), poly(dimethylsiloxane) (PDMS), and octadecyltrichlorosilane (OTS)-modified SiO 2 . OFETs based on 6,13-dichloropentacene (DCP) microwires (MWs) with CYTOP as the insulator layer were fabricated, which exhibited excellent device performance. Much improved device stability with very low mobility degradation (less than 9%) was observed after 24 days. While devices fabricated on hydrophilic insulators of poly-(vinyl phenol) (PVP) and bare SiO 2 experienced dramatic performances decay within 24 days. Furthermore, by using metal-assisted photolithography method, flexible OFETs arrays could be further fabricated on polyethylene naphthalate (PEN) substrate, which showed excellent mechanical bending flexibility and stability. This work unveils the great potential of metal-assisted photolithography method for long-term stable high-integration organic electronic devices. [ABSTRACT FROM AUTHOR]

• 1. The optimal optical sensor is selected and systematically studied to determine the detection object. • 2. The real-time synchronous measurement of multi parameters is realized with multi parameter matrix. • 3. The optimized cascade mode is combined with WGM technology to realize the integration of sensors. Multi parameter measurement based on optical fiber sensor has been a research hotspot in recent years. In this work, four kinds of optical fiber sensors, LPFG, FBG, PMF and SMS are used. The transmission characteristics and sensing characteristics of each sensor are analyzed in detail. Based on the modulation of resonance wavelength by environmental variables, the accurate and synchronous real-time detection of temperature, stress, refractive index and humidity is realized. We use all-optical coupling cascade and wavelength division multiplexing (WDM) technology to prepare a highly integrated sensing device. The problem of signal crosstalk of each sensor is solved, and the cost of signal transmission and reception is greatly reduced. It is of great significance for monitoring a variety of environmental variables under extreme conditions. [ABSTRACT FROM AUTHOR]

Single-chip 60 GHz transmitter (TX) and receiver (RX) MMICs have been designed and characterized in a 0.15 µm (fT ~ 120 GHz/fMAX > 200 GHz) GaAs mHEMT MMIC process. This paper describes the second generation of single-chip TX and RX MMICs together with work on packaging (e.g., flip-chip) and system measurements. Compared to the first generation of the designs in a commercial pHEMT technology, the MMICs presented in this paper show the same high level of integration but occupy smaller chip area and have higher gain and output power at only half the DC power consumption. The system operates with a LO signal in the range of 7-8 GHz. This LO signal is multiplied in an integrated multiply-by-eight (X8) LO multiplier chain, resulting in an IF center frequency of 2.5 GHz. Packaging and interconnects are discussed and as an alternative to wire bonding, flip-chip assembly tests are presented and discussed. System measurements are also described where bit error rate (BER) and eye diagrams are measured when the presented TX and RX MMICs transmits and receives a modulated signal. A data rate of 1.5 Gb/s with simple ASK modulation was achieved, restricted by the measurement setup rather than the TX and RX MMICs. These tests indicate that the presented MMICs are especially well suited for transmission and reception of wireless signals at data rates of several Gb/s. [ABSTRACT FROM AUTHOR]

Highly integrated transmitter and receiver MMICs have been designed in a commercial 0.15 µm, 88 GHz fT/183 GHz fMAX GaAs pHEMT MMIC process and characterized on both chip and system level. These chips show the highest level of integration yet presented in the 60 GHz band and are true multipurpose front-end designs. The system operates with an LO signal in the range 7-8 GHz. This LO signal is multiplied in an integrated multiply-by-eight (X8) LO chain, resulting in an IF center frequency of 2.5 GHz. Although the chips are inherently multipurpose designs, they are especially suitable for high-speed wireless data transmission due to their very broadband IF characteristics. The single-chip transmitter MMIC consists of a balanced resistive mixer with an integrated ultra-wideband IF balun, a three-stage power amplifier, and the X8 LO chain. The X8 is a multifunction design by itself consisting of a quadruplet, a feedback amplifier, a doubler, and a buffer amplifier. The transmitter chip delivers 3.7 ± 1.5 dBm over the RF frequency range of 54-61 GHz with a peak output power of 5.2 dBm at 57 GHz. The single-chip receiver MMIC contains a three-stage low-noise amplifier, an image reject mixer with an integrated ultra-wideband IF hybrid and the same X8 as used in the transmitter chip. The receiver chip has 7.1 ± 1.5 dB gain between 55 and 63 GHz, more than 20 dB of image rejection ratio between 59.5 and 64.5 GHz, 10.5 dB of noise figure, and -11 dBm of input-referred third-order intercept point (11P3). [ABSTRACT FROM AUTHOR]