Uplink Sensing Using CSI Ratio in Perceptive Mobile Networks

Uplink sensing in perceptive mobile networks (PMNs), which uses uplink communication signals for sensing the environment around a base station, faces challenging issues of clock asynchronism and the requirement of a line-of-sight (LOS) path between transmitters and receivers. The channel state information (CSI) ratio has been applied to resolve these issues, however, current research on the CSI ratio is limited to Doppler estimation in a single dynamic path. This paper proposes an advanced parameter estimation scheme that can extract multiple dynamic parameters, including Doppler frequency, angle-of-arrival (AoA), and delay, in a communication uplink channel and completes the localization of multiple moving targets. Our scheme is based on the multi-element Taylor series of the CSI ratio that converts a nonlinear function of sensing parameters to linear forms and enables the applications of traditional sensing algorithms. Using the truncated Taylor series, we develop novel multiple-signal-classification grid searching algorithms for estimating Doppler frequencies and AoAs and use the least-square method to obtain delays. Both experimental and simulation results are provided, demonstrating that our proposed scheme can achieve good performances for sensing both single and multiple dynamic paths, without requiring the presence of a LOS path

Pyrolysis treatment of nonmetal fraction of waste printed circuit boards : Focusing on the fate of bromine

Advanced thermal treatment of electronic waste offers advantages of volume reduction and energy recovery. In this work, the pyrolysis behaviour of nonmetallic fractions of waste printed circuit boards was studied. The fate of a bromine and thermal decomposition pathway of nonmetallic fractions of waste printed circuit boards were further probed. The thermogravimetric analysis showed that the temperatures of maximum mass loss were located at 319°C and 361°C, with mass loss of 29.6% and 50.6%, respectively. The Fourier transform infrared Spectroscopy analysis revealed that the spectra at temperatures of 300°C–400°C were complicated with larger absorbance intensity. The nonmetallic fractions of waste printed circuit boards decomposed drastically and more evolved products were detected in the temperature range of 600°C–1000°C. The gas chromatography–mass spectrometry analysis indicated that various brominated derivates were generated in addition to small molecules, such as CH4, H2O and CO. The release intensity of CH4 and H2O increased with temperature increasing and reached maximum at 600°C–800°C and 400°C–600°C. More bromoethane (C2H5Br) was formed as compared with HBr and methyl bromide (CH3Br). The release intensity of bromopropane (C3H7Br) and bromoacetone (C3H5BrO) were comparable, although smaller than that of bromopropene (C3H5Br). More dibromophenol (C6H4Br2O) was released than that of bromophenol (C6H5BrO) in the thermal treatment. During the thermal process, part of the ether bonds first ruptured forming bisphenol A, propyl alcohol and tetrabromobisphenol A. Then, the tetrabromobisphenol A decomposed into C6H5BrO and HBr, which further reacted with small molecules forming brominated derivates. It implied debromination of raw nonmetallic fractions of waste printed circuit boards or pyrolysis products should be applied for its environmentally sound treating.© 2020 Sage. The article is protected by copyright and reuse is restricted to non-commercial and no derivative uses. Users may also download and save a local copy of an article accessed in an institutional repository for the user's personal reference.fi=vertaisarvioitu|en=peerReviewed

Identification of Potential Key Genes Associated With the Pathogenesis and Prognosis of Gastric Cancer Based on Integrated Bioinformatics Analysis

Background and Objective: Despite striking advances in multimodality management, gastric cancer (GC) remains the third cause of cancer mortality globally and identifying novel diagnostic and prognostic biomarkers is urgently demanded. The study aimed to identify potential key genes associated with the pathogenesis and prognosis of GC.Methods: Differentially expressed genes between GC and normal gastric tissue samples were screened by an integrated analysis of multiple gene expression profile datasets. Key genes related to the pathogenesis and prognosis of GC were identified by employing protein–protein interaction network and Cox proportional hazards model analyses.Results: We identified nine hub genes (TOP2A, COL1A1, COL1A2, NDC80, COL3A1, CDKN3, CEP55, TPX2, and TIMP1) which might be tightly correlated with the pathogenesis of GC. A prognostic gene signature consisted of CST2, AADAC, SERPINE1, COL8A1, SMPD3, ASPN, ITGBL1, MAP7D2, and PLEKHS1 was constructed with a good performance in predicting overall survivals.Conclusion: The findings of this study would provide some directive significance for further investigating the diagnostic and prognostic biomarkers to facilitate the molecular targeting therapy of GC

Surface free energy and mechanical performance of LDPE/CBF composites containing toxic-metal free filler

Heavy-metal contamination in children's toys is a widespread problem, and the international community has issued a series of safety standards to restrict and control the use of toxic metals in toys. In this work, a colored filler (CBF) was prepared using pearl oyster shell (POS) as the green raw material and azo dye as the colorant. Its surface properties were subsequently studied in comparison to those of POS powder using the inverse gas chromatography method. The dispersion surface free energy profiles for both CBF and POS showed that this component contributed the major part (> 70%) to the total surface free energy. The CBF possessed lower polar surface free energy and was relatively more hydrophobic. It also showed a lower thermodynamic work of cohesion, allowing its better dispersion in a low density polyethylene (LDPE) matrix. Mechanical performance studies showed that adding CBF could significantly increase the tensile strength, elastic modulus, flexural strength and flexural modulus of LDPE composites. The absence of toxic metals coupled with excellent mechanical performance makes the CBF an ideal candidate as a filler for children's toys fabrication.The authors gratefully acknowledge financial support from the National Natural Science Foundation of China (Grant nos. 51606055 and 41373121) and Zhejiang Provincial Natural Science Foundation of China (Grant no. LY14D010009).info:eu-repo/semantics/publishedVersio

The generation and migration of bubbles in oil-pressboard insulation needle-plate system

Bubbles in transformer oil can easily lead to partial discharge, which can deteriorate the transformer oil and even breakdown the transformer insulation. To clarify the migration process and the characteristics of bubbles generated in an oil-immersed power transformer exposed to an extremely uneven electric field, we experimentally monitor these phenomena under an extremely nonuniform AC electric field and numerically simulate the migration distance and the migration speed of bubbles with different initial positions and sizes. The results show that the streamer discharge channel formed by a partial discharge in oil is gasified into a bubble channel. After it collides with the surface of the pressboard, its morphology is transformed into approximately spherical bubbles due to the surface tension of the gas-liquid interface. After bubbles are generated in the oil, they move away from areas with a strong electric field due to the electric-field force and gradually approach the oil surface due to the buoyancy force. The experimental results are consistent with the simulation results, which verify the rationality of the simulation model

Impact of gamma-glutamyl carboxylase gene polymorphisms on warfarin dose requirement: A systematic review and meta-analysis

AbstractBackgroundThe Gamma-glutamyl carboxylase (GGCX) gene, as with Vitamin K Epoxide Reductase Complex Subunit 1(VKORC1), CytochromeP450 Complex Subunit 14 F2 (CYP4F2) and CytochromeP450 Complex Subunit2C9 (CYP2C9), is a candidate predictor for appropriate maintenance warfarin dose. However, the association between GGCX gene polymorphisms and warfarin dose requirement is still controversial. To quantify the influence of GGCX polymorphisms on warfarin dose requirements, we performed a systematic review and meta-analysis.MethodsAccording to PRISRM statement (Preferred reporting items for systematic reviews and meta-analyses), a comprehensive literature search was undertaken through August 2014 looking for eligible studies in Embase, Pubmed,Web of Science and the Cochrane Library. The impact of GGCX polymorphisms on mean daily warfarin dose (MDWD) was counted by means of Z test. RevMan 5.2.7 software (developed by the Cochrane Collaboration) was applied to analyze the relationship between GGCX gene polymorphisms and warfarin dose requirements.ResultsNineteen articles including 21 studies with a total of 6957 patients were included in the meta-analysis. Among three investigated single nucleotide polymorphisms (SNPs), rs11676382 showed higher CC genotype frequencies in Asian than those in Caucasian(97.7% vs. 86.9%); patients who were “G carriers” (that is, carried the GGCX rs11676382 CG or GG genotypes) required 27% lower warfarin dose than CC genotype[95%Confidence Interval(CI)=17%-37%, P=0.000, I2%=82.0 and PQ=0.000], moreover, stratified analysis by ethnicity showed similar results in Caucasian(23% lower, 95%CI=12%-33%), but not in Asian. With respect to genetic variation of rs699664 and rs121714145 SNPs, no significant impact on warfarin dose requirements were demonstrated.ConclusionsThis meta-analysis suggested that GGCX rs11676382 polymorphism may be one of factors affecting the dose of warfarin requirement, and the effects are different in different ethnicities. Further studies about this topic in different ethnicities with larger samples are expected to be conducted to validate our results

Kinetic modeling study on the combustion treatment of cathode from spent lithium-ion batteries

Thermal treatment offers an alternative method for the separation of aluminum foil and cathode materials during spent lithium-ion batteries recycling. In this work, the combustion kinetic of cathode was studied based on six model-free (isoconversional) methods, namely Flynn-Wall-Ozawa (FWO), Friedman, Kissinger-Akahira-Sunose, Starink, Tang, and Boswell methods. The possible decomposition mechanism was also probed using a master-plots method (Criado method). Thermogravimetric analysis showed that the whole thermal process could be divided into three stages with temperatures of 37-578 degrees C, 578-849 degrees C, and 849-1000 degrees C. The activation energy (E alpha) derived from these model-free methods displayed the same trend, gradually increasing with a conversion range of 0.002-0.013, and significantly elevating beyond this range. The coefficients from the FWO method were larger, and the resulted E alpha fell into the range of 10.992-40.298 kJ/mol with an average value of 20.228 kJ/mol. Comparing the theoretical master plots with an experimental curve, the thermal decomposition of cathode could be better described by the geometric contraction models

Liquid-Metal-Based Magnetic Controllable Soft Microswitch with Rapid and Reliable Response for Intelligent Soft Systems

When combined with diverse sensors, soft robots significantly improve their functionalities and intelligence levels. However, most of the existing soft sensors require complex signal analysis devices or algorithms, which severely increase the complexity of soft robot systems. Here, based on the unique fluidic property of liquid metal, we propose a magnet-controllable soft microswitch that can be well-integrated into a soft robot system, e.g., a soft gripper to help it facilely detect and precisely grab objects. The microswitch consists of a flexible soft beam electrode and a fixed electrode, forming a soft microsystem. By tuning the cohesion force of the liquid metal between the electrodes, the microswitch can convert its states between an individual and a self-locking state. The microswitch can achieve a reasonable rapid response (~12 ms) and high switching frequency (~95 Hz). Furthermore, soft microswitches can be customized into logic units and also coupled to control a digital tube showing various numbers. Our work provides a new simple soft sensor unit that may enhance the intelligence of soft systems

Recycling of typical difficult-to-treat e-waste: Synthesize zeolites from waste cathode-ray-tube funnel glass

The disposal of waste cathode ray-tubes (CRTs) from old televisions and discarded computer monitors has become a major environmental concern worldwide. In this work, an open-loop recycling method was developed to synthesize zeolites using CRT funnel glass as the raw material. The effects of hydrothermal temperatures and pressure, n(SiO2/Al2O3) molar ratios and hydrothermal time on the resulting products were investigated. The results indicated that hydrothermal temperatures and pressure played critical roles in zeolite synthesis. Amorphous phases were detected at lower temperatures (80-100 degrees C) and pressure (0.47-1.01 bar) with n(SiO2/Al2O3)=2.0. At the temperature of 110 degrees C (pressure 1.43 bar), NaA formed with a mixture of NaP1 and Faujasite. With further increase in the temperature and pressure, the unstable NaA and Faujasite disappeared, and Hydroxysodalite developed. The influence of n(SiO2/Al2O3) ratios on resulting products revealed a single phase of NaA was formed at the ratio of 1.5 and a mixture of NaA and Faujasite at the ratio of 2.0. Prolonging hydrothermal time, however, could promote zeolite crystallization, and NaA gradually developed with an increase in the time from 2 to 6 h at n(SiO2/Al2O3)=1.5. By comparison, crystallization phases were observed only when the time was longer than 8 h at n(SiO2/Al2O3)=2.0. (C) 2016 Published by Elsevier B.V

Dual Drive Curve Tool Path Planning Method for 5-axis NC Machining of Sculptured Surfaces

AbstractThe problem of finished surface being not first-order continuous commonly exists in machining sculptured surfaces with a torus cutter and some other types of cutters. To solve this problem, a dual drive curve tool path planning method is proposed in this article. First, the maximum machining strip width of a whole tool path can be obtained through optimizing each tool position with multi-point machining (MPM) method. Second, two drive curves are then determined according to the obtained maximum machining strip width. Finally, the tool is positioned once more along the dual drive curve under the condition of tool path smoothness. A computer simulation and cutting experiments are carried out to testify the performance of the new method. The machined surface is measured with a coordinate measuring machine (CMM) to examine the machining quality. The results obtained show that this method can effectively eliminate sharp scallops between adjacent tool paths, keep tool paths smooth, and improve the surface machining quality as well as machining efficiency