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The direct tensile resistance of strain-hardening steel-fibre-reinforced concrete (SHSFRC) was experimentally investigated and modelled. Three steel fibre types (twisted, hooked and smooth fibres) and three matrices with different compressive strengths (28 MPa (M1), 84 MPa (M2) and 180 MPa (M3)) were investigated in both single-fibre pull-out tests and direct tensile tests. A model based on machine learning was developed to predict the tensile resistance of the SHSFRCs. The experimental results showed that the twisted fibres not only exhibited the highest pull-out resistance but also the greatest tensile resistance in M1 and M2, whereas smooth fibres achieved the same results in M3. The predicted outcomes showed that the proposed model had high efficiency and accuracy in estimating the tensile resistance of SHSFRC, with a correlation coefficient of 0.951.

Rocks contain a large number of elements such as Na, K, Ca, Mg, Fe, Mn, and Ti. The determination of those element contents is important in geological and geographical exploration as well as the original identification and classification of rocks. Currently, the analysis of the elemental composition of rocks can be carried out on equipments such as ICP-OES, ICP-MS,... However, in some laboratories with limited conditions, the analysis has many difficulties. In the present study, we analyzed rock samples after being treated by microwave using flame atomic and molecular absorption spectroscopy. The results showed that the content of elements in the range of Na (0.31 – 2.46%), K (1.38 – 3.71%), Ca (0.08 – 0.23%), Mg (0.16 – 0.69%), Fe (2.38 – 5.19) %), Mn(0.08 – 0.1%) and Ti(0.12 – 0.36%). The study provides a simple and cost-effective method for rock analysis.

The study focused on reviewing modern and effective drying methods assisted by infrared radiation, microwave and radio frequency. In which, the drying results of previous studies were reviewed to clarify the drying efficiency of drying methods with the support of infrared radiation, microwave and radio frequency. The review results showed that the radiant heating mechanism of infrared radiation and the volumetric heating mechanism of microwave and radio frequency supported the process of material heating and moisture diffusion within the material. As a result, the drying process achieved high drying efficiency, the drying time was significantly shortened and the quality of the dried products was improved both in terms of sensory quality and nutritional quality. The study of the application of infrared radiation, microwave and radio frequency in drying technique had a high scientific, technological and practical significance. This would be the foundation for finding suitable drying methods and drying modes to improve drying efficiency as well as the quality of dried products.

BACKGROUND AND AIMS The hepatic venous pressure gradient (HVPG) is the standard for estimating portal pressure but requires expertise for interpretation. We hypothesized that HVPG could be extrapolated from liver histology using a machine learning (ML) algorithm. APPROACH AND RESULTS Patients with NASH with compensated cirrhosis from a phase 2b trial were included. HVPG and biopsies from baseline and weeks 48 and 96 were reviewed centrally, and biopsies evaluated with a convolutional neural network (PathAI, Boston, MA). Using trichrome-stained biopsies in the training set (n = 130), an ML model was developed to recognize fibrosis patterns associated with HVPG, and the resultant ML HVPG score was validated in a held-out test set (n = 88). Associations between the ML HVPG score with measured HVPG and liver-related events, and performance of the ML HVPG score for clinically significant portal hypertension (CSPH) (HVPG ≥ 10 mm Hg), were determined. The ML-HVPG score was more strongly correlated with HVPG than hepatic collagen by morphometry (ρ = 0.47 vs. ρ = 0.28; P

This study focused on the experimental drying of Bo Chinh ginseng by the ultrasound-assisted heat pump drying method, in which the effects of drying air temperature (T), ultrasonic power (P), intermittency ratio of ultrasound generator (A) on the moisture effective diffusion coefficient (Deff), saponin content (Sp) and color change (dE) during the drying process were determined. The results showed that the drying time was reduced from 12.5 h at 35 °C to 8.9 h at 40 °C and greatly reduced to 5.8 h at 55 °C. The moisture diffusion coefficient Deff and color change index increased with the increase in drying temperature. Meanwhile, from 35 °C to 45 °C, the saponin content after drying tended to increase gradually, but when the temperature continued to rise from 45 °C to 55 °C, the saponin content decreased. The effect of ultrasonic power in the drying process was in particular as follows. The drying time of 8.8 h at 40 W ultrasonic power reduced to 7.8 h at 80 W ultrasonic power, and reduced to 7 h at 160 W ultrasonic power. The remaining saponin content after drying tended to increase gradually at the power level of 40–120 W (from 89.2% to 95.2%) and decrease when the power increased from 120 to 160 W (from 95.2% to 90.5%). The moisture diffusion coefficient Deff also increased with the increase in ultrasonic power. Meanwhile, the color change of dried products decreased as the ultrasonic power increased in the range of 40–120 W but increased with the ultrasonic power range from 120 to 160 W. Additionally, the experimental method and Box–Behnken design were used for optimizing the drying process with the optimal drying conditions such as drying air temperature of 45.2 °C, ultrasonic power of 127.7 W and intermittency ratio of ultrasound generator of 0.18.

Energy plays an important role in economic growth and environmental protection, is an important input of many manufacturing industries, and one of the essential commodities of households. The proce...

This paper explores the role of school quality in immigrants’ home countries on their earnings in Germany, using native Germans as a benchmark. We propose an empirical analysis that highlights two important insights. First, there is a substantial gap in the returns to education between natives and immigrants in Germany, especially when we consider the quality of schooling in the source country where education was obtained. In particular, lower school quality reduces the endowment advantage that immigrants possess from their education. Second, quality-adjusted education helps us to better understand the potential driving force behind the native–immigrant wage gap. We show that this measure accounts for a substantial fraction of the unexplained part in the Oaxaca–Blinder decomposition. These findings emphasize the role of the school quality in explaining the imperfect transferability of human capital of immigrants in Germany.

This article presents a systematic empirical modeling approach in fully depleted silicon-on-insulator (FDSOI) CMOS for large-signal simulation in power amplifier applications. The model is constructed from multibias S-parameter measurements up to 67 GHz. The frequency dispersions in transconductance and output conductance are addressed by two independent radio frequency (RF) current sources. Angelov’s current formula is modified to adapt to the FDSOI transistors. Load-pull measurements are performed for the large-signal verification in a non-50- $\Omega $ environment. The model accurately predicts the nonlinear characteristics of the device under test and the harmonic components. The time-domain waveforms also show excellent agreement to the simulation.

The main purpose of this study was to select the appropriate ultrasound parameters that support the freezing process of Bo Chinh ginseng. This process involves placing Bo Chinh ginseng in an open-air environment and ensuring that the transducer does not come into contact with the material. The research results show that the ultrasound power, ultrasound irradiation temperature and intermittency ratio all affect the freezing time, nucleation temperature, color and microstructure of the materials. When the ultrasound continuously operated during the freezing process, at a frequency of 20 kHz, there was a 29.1% reduction in the freezing time at a power level of 100 W as compared to freezing without the help of ultrasound irradiation. The irradiation temperature and nucleation temperature have a linear relationship (y=−0.35x−0.93) which can help to control the nucleation temperature, thereby changing the ice crystal size. Ultrasound-assisted freezing at a 0.6 intermittency ratio had the shortest freezing time. The microstructure of the material changed after ultrasound-assisted freezing and many microchannels and holes were generated. When frozen at a wave rate of 0.4, the microchannels that were created in the material effectively supported the process of water drainage in the drying sublimation stage. At the same time, ultrasound irradiation did not affect the color of the post-freezing material when compared to the color of the frozen material that did not undergo ultrasound irradiation.

A microwave characterization at UHF band of a ferroelectric hafnium zirconium oxide metal-ferroelectric-metal (MFM) capacitors for varactor applications has been performed. By using an impedance reflectivity method, a complex dielectric permittivity was obtained at frequencies up to 500 MHz. Ferroelectric Hf0.5Zr0.5O2 of 10 nm thickness has demonstrated a stable permittivity switching in the whole frequency range. A constant increase of the calculated dielectric loss is observed, which is shown to be an effect of electric field distribution on highly resistive titanium nitride (TiN) thin film electrodes. The C-V characteristics of a “butterfly” shape was also extracted, where the varactors exhibited a reduction of capacitance tunability from 18.6% at 10 MHz to 15.4% at 500 MHz.

The hot air recirculating drying method has the advantage of handling large output. Moreover, in the drying chamber with a large volume of drying material, factors affecting the drying process such as air flow rate, temperature, drying agent humidity, and surface area of the drying product are always concerned. Because this is the deciding factor for the drying time as well as the quality of the drying product. However, the drying time is closely related to the energy consumed in the drying system. In particular, the temperature and humidity of the environment have a great influence on energy consumption. This paper has built a general mathematical model, using ARIMA algorithm to predict energy consumption for the industrial drying system and applying the mathematical model to actually survey the drying system with a capacity of 1000 kg /batch, 03 drying chambers are designed with a size of 3000mm. x 3000mm x 2500 (length x width x height), total drying tray area 192 m2. Energy sources use thermal oil furnace technology or resistive furnaces. The collected temperature and humidity data is based on the IoT platform. The simulation results forecast the temperature accurately to 99.09%, the humidity is accurate to 98.24% and the energy consumption reaches 96.31%.

In this work, we propose a smart shoe integrated with a very-low power wireless sensor node operating in Bluetooth Low Energy (BLE) 5.0 standard. The sensor node consists of a miniaturized printed inverted-F antenna, an accelerometer and a gyroscope being placed at the bottom of the shoe to measure footstep-length, running speed and foot landing angle. The maximum power consumption of the sensor is 11 mW and it is sustained by a triboeletric nanogenerator (TENG) which generates power from the friction causing by user's motion itself and an energy storage circuit. The triboelectric energy harvester, having the size of 6 cm × 6 cm, is made of multiple pairs of triboelectric materials can harvest up to 32 mW/m2, enough to supply the sensor node.

In this paper, a two-stage damage detection method combining modal strain energy (MSE) method and genetic algorithm (GA) is proposed to identify the location and the extent of multiple damages in space frame structures. The proposed method can detect the damages not only globally in whole structure but also locally in each structural member. In the first stage, a damage index based on the MSE, namely modal strain energy based index (MSEBI), is employed as the criterion to determine the occurrence of the damages among elements in the structure. The MSE is calculated by using the modal analysis obtained from the frame’s finite element model. In the second stage, the GA is utilized to minimize the objective function. The objective function is developed with designed variables correspondingly representing the extent of the damages, which are identified from the first stage. The feasibility of the proposed method is verified by numerical simulation of a real scale space frame structures. Finally, discussions about the proposed method are given.

In this paper, a comprehensive analysis on small-signal modeling of mm-wave transistor in 22nm FDSOI technology is presented. The model is constructed based on experimental S-parameters up to 110 GHz of a 22FDX® thick-oxide n-MOSFET and analytical parameter extraction approach. The non-quasi static effect is addressed thoroughly in the equivalent circuit model for high frequency validity. The bias-dependent series source and drain resistances are considered to account for the overlap regions between the gate and the highly doped source/drain regions. In addition, a simple RC network is included at the output to model the innegligible substrate coupling at mm-wave frequencies. Excellent agreements between model prediction and measurement are observed in the interested bandwidth for various bias conditions.

Osmotic membrane bioreactors (OsMBRs) are a recent breakthrough technology designed to treat wastewater. Nevertheless, their application in high-salinity wastewater treatment is not widespread because of the effects of saline conditions on microbial community activity. In response, this study developed an integrated sponge biocarrier-OsMBR system using highly salt-tolerant microorganisms for treating saline wastewater. Results showed that the sponge biocarrier-OsMBR obtained an average water flux of 2 L/m 2 h during a 92-day operation when 1 M MgCl 2 was used as the draw solution. The efficiency in removing dissolved organic compounds from the proposed system was more than 99%, and nutrient rejection was close to 100%, indicating excellent performance in simultaneous nitrification and denitrification processes in the biofilm layer on the carriers. Moreover, salt-tolerant microorganisms in the sponge biocarrier-OsMBR system worked efficiently in salt concentrations of 2.4%. A polytetrafluoroethylene MD membrane (pores = 0.45 μm) served to regenerate the diluted draw solution in the closed-loop system and produce high-quality water. The moving sponge biocarrier-OsMBR/MD hybrid system demonstrated its potential to treat salinity wastewater treatment, with 100% nutrient removal and 99.9% conductivity rejection.

Membrane technology has become a common separation technology over the past decennia. Membranes are used more and more for the production of drinkable water from groundwater, surface water and wastewater. Membranes are now competitive versus conventional techniques. Desalination is predominantly used to eradicate the problem of water scarcity. The sustainability of all desalination processes depends mainly on the reduction of energy costs (production cost) and the increase in water recovery. Forward osmosis and membrane distillation are emerging technologies for sustainable desalination. Here we review membrane processes of forward osmosis and membrane distillation and the advancements in membrane material and modules. We also discuss the capability of membrane distillation in treating highly concentrated aqueous solutions derived from other desalination processes. Furthermore, the advancements in fabrication of high-performance membrane is reviewed and the performance of different membranes and optimization of membrane distillation process are summarized.

This work presents a detailed study on the high-frequency performance of 22FDX® FDSOI for 5G front-end power amplifiers. The following report focuses on the S-parameters and large-signal figure-of-merits such as output power, gain and power-added efficiency for an insightful and correct assessment on the device capability. DC characteristics of the test transistors are firstly investigated to determine the optimum operating point. Small-signal characterization is performed up to 110 GHz using a state-of-the-art mm-Wave measurement setup. An overall MSG/MAG of 16 ± 4 dB is recorded in the frequency range 10 - 80 GHz. On the other hand, large-signal performance on non-50 Ohm impedance environment is evaluated thoroughly through vector-receiver load-pull measurement up to 24 GHz. The measured output power and efficiency indicate that the DUTs perform well in the sub-6 GHz band and even in K-band. The outstanding experimental results emphasize the applicability and suitability of the 22FDX® FDSOI technology platform for 5G low-power transmitters.

This paper investigates the applicability of a thick-oxide transistor from the 22FDX® for 5G NR sub-6 GHz front-end modules. Characterization and evaluation of the GlobalFoundries's FDSOI n-MOSFET regarding RF front-end figure-of-merits, such as output power, efficiency and linearity are discussed. Load-pull measurements are performed to extract the optimal performance. The test transistor delivers saturation power of +5.0 dBm and more than 65% of PAE while maintaining flat transducer gain of 10.2 ± 0.2 dB across the targeted frequency range for a 1.5 V single-ended class AB operation. Besides, the low PAE roll-off in term of reducing supply voltage and the particular 60% PAE at 10 dB output back-off indicate that the DUTs are well suitable for envelope tracking applications. Additional reliability tests at strong compression levels are conducted from which low performance degradation over time is observed even at 9 dB output compression.

This paper presents a tunable 60 GHz band-pass filter, based on a coplanar waveguide (CPW) transmission line, periodically loaded with ferroelectric Hafnium Zirconium Oxide (HZO) variable metal-ferroelectric-metal (MIM) capacitors (varactors), developed for back-end-of-line (BEoL) integration. Derived from the nonlinear capacitance of hafnium zirconium oxide and implementing the method-of-moments simulation, it was shown, that with changing the bias voltage between 0.95 and -3 V, the filter’s center frequency can be tuned between 60.5 and 69,7 GHz, respectively. Hereby, a minimum insertion loss of -3.3 dB is realized. The chip area of the filter is only 0.062 mm2, making it the smallest among tunable V-band filters.

This paper presents a 60 GHz phase shifter, based on a coplanar waveguide (CPW) transmission line, loaded with ferroelectric hafnium zirconium oxide (HZO) variable metal-insulator-metal (MIM) varactors, developed for the back-end-of-line (BEoL) on-chip integration. Using the measured data of capacitance-voltage (C-V) characteristics of HZO and implementing the method-of-moments simulation, it was shown, that by changing the bias voltage between 0.95 and -3 V, the device shows a phase shift of 111° and a minimum insertion loss of -5.84 dB at 60 GHz. The chip area of the device is 0.206 mm2, making it the smallest among non-CMOS phase shifters.

Die Weiterbildung von Beschäftigten gewinnt durch die digitale Entwicklung, demografische Veränderungen sowie die zunehmende internationale Verflechtung immer mehr an Bedeutung. Dies gilt auch für Menschen mit Migrationshintergrund. Fast ein Drittel der deutschen abhängig Erwerbstätigen ohne Migrationshintergrund nahm von 2013 bis 2015 an mindestens einer beruflichen Weiterbildung teil. Bei den selbst Eingewanderten (1. Generation) sind dies 20 Prozent. In Deutschland geborene Beschäftigte mit mindestens einem eingewanderten Elternteil (2. Generation) bilden sich ähnlich häufig weiter wie Deutsche ohne Migrationshintergrund. Die höchste Teilnahmequote an Weiterbildung weisen mit 35 Prozent die abhängig erwerbstätigen Frauen der 2. Generation auf. Sie sind meist gut qualifiziert und arbeiten oft in qualifizierten Angestelltenpositionen sowie in weiterbildungsintensiven Branchen wie dem Erziehungs- und Gesundheitsbereich und der Öffentlichen Verwaltung. Solche Faktoren begünstigen die Teilhabe an Weiterbildung. Anstrengungen, um die Teilhabe an Weiterbildung zu erhöhen, sollten sich vor allem auf die selbst Eingewanderten der 1. Generation beziehen. Bedeutsam sind für diesen Personenkreis aber auch Ausbildung oder Studium sowie die Anerkennung mitgebrachter beruflicher Qualifikationen.

This paper presents a wideband high efficiency GaN-HEMT balanced power amplifier for modern communication systems. Source- and load-pull analyses through simulations as well as pre-matching technique are applied to design the branch amplifiers. The matching networks comprise the 4:1 binomial impedance transformers to step down the $\mathbf{50}\ \Omega$ system impedance. Broadband SMD quadrature hybrid couplers are implemented to form the balanced configuration. The realized amplifier exhibits small-signal gain of $\mathbf{13.5}\pm \mathbf{2\ dB}$ over the target frequency range 1.3-3.6 GHz while maintaining well-matched conditions at both input and output. Large-signal measurements show that the amplifier properly deliver $\mathbf{47.5}\pm \mathbf{1.2\ dBm}$ continuous wave output power with an average power-added efficiency (PAE) of 55 % across the desired bandwidth.

This study has been motivated to evaluate the practicality of numerical simulation of impedance monitoring for bolt-loosening detection in steel column connection. In order to achieve the objective, the following approaches are implemented. Firstly, the theory of electro-mechanical (E/M) impedance responses and impedance-based damage monitoring method are outlined. Secondly, the feasibility of numerical simulation of impedance monitoring is verified for several pre-published experimental examples on steel beams, cracked aluminum beams, and aluminum round plates. Undamaged and damaged steel and aluminum beams are simulated to compare to experimental impedance responses. An aluminum round plate with PZT patch in center is simulated to investigate sensitive range of impedance responses. Finally, numerical simulation of the impedance-based damage monitoring is performed for a steel column connection in which connection bolts are damaged. From the numerical simulation test, the applicability of the impedance-based monitoring to the target steel column connection can be evaluated.

In this paper, design of a wideband high efficiency GaN-HEMT power amplifier operating in 1.9–2.9 GHz is presented. The amplifier is stabilized optimally for mean gain degradation over the frequency range by following a two-step process. Source- and load-pull simulations are applied to determine the optimum impedances for the transistor. Besides, harmonic load impedances are also considered to ensure high efficiency. The proposed amplifier is fabricated and evaluated for performance with both small-signal and large-signal measurement. Measurement results shows good agreement to simulation. The amplifier exhibits small-signal gain of 13–16 dB in the desired bandwidth. Large-signal measurement with an input power level of 24.5 dBm indicates that the designed amplifier meets the output power requirement and attains power-added efficiency (PAE) from 37–69% in the desired bandwidth.

The design of a four-port scalar reflectometer operating at center frequency 2.4 GHz is presented in this paper. The proposed reflectometer is constructed from two 10 dB branch-line couplers, which are produced in microstrip line technique. Parameters of the realized device are in good agreement with simulation results. Directivity of the two couplers is over 22 dB at the center frequency. The reflection coefficient is below −20 dB for a bandwidth of 1 GHz. Power detector Linear Technology LT5581, which has 40 dB dynamic range at frequencies from 0.8 to 2.6 GHz, is installed to measure the scalar reflection coefficient of a Device Under Test (DUT). Since both used components have their limitations, this paper discusses the process of determining the restricted accuracy of such a scalar reflectometer for applications relating to microwave amplifiers. The reflectometer was tested at a single frequency of 2.4 GHz. The final result points out that −18 dB is the reachable limit of this reflectometer and a method is proposed to predict the scalar reflection coefficient.