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A series of inexpensive electroplating sludge-derived magnetic copper-containing catalysts were developed for the selective hydrogenation of biomass-based furfural (FFR) into furfuryl alcohol (FA) and 2-methylfuran (MF). The specific structural characteristics of as-prepared magnetic copper-containing samples were clearly identified through various techniques, including XRD, XPS, N2 adsorption–desorption, NH3-TPD, SEM and so on. The characterizations revealed that the hydrogen pre-activated magnetic catalysts supplied metallic Cu species, medium acidity and porosity for the catalytic upgrading of FFR in hydrogen atmosphere. As for FFR-to-FA as well as FFR-to-MF transformations, the magnetic copper-containing catalyst with calcination temperature of 800 °C exhibited excellent performance towards the formation of FA and MF, wherein desirable FA yield of 98.5 mol% and MF yield of 71.3 mol% were achieved at reaction temperatures of 160 °C and 240 °C, respectively. The reuse experiments indicated that the recycled catalysts still maintained excellent activity and stability even after four-time recycling. The present study thus highlights a new approach for the resource utilization of electroplating sludge, which also supplies low-cost and efficient catalytic materials for the selective upgrading of various biomass-derived platform molecules. [ABSTRACT FROM AUTHOR]

Modern applications need to flexibly adjust the processing process according to the different environments and real-time processing, thus putting forward higher requirements for the reconfiguration performance of coarse-grained reconfigurable architecture (CGRA). Traditional dynamic reconfiguration requires constant configuration of the processor by the host computer. Still, this reconfiguration method severely restricts switching different tasks, making it difficult to achieve dynamic real-time reconfiguration and limiting performance improvement. This paper presents a real-time monitoring-based self-reconfiguration mechanism (RMSRM) based on the implementation of CGRA. This mechanism improves the reconfiguration performance by monitoring the execution process of the array in real-time through a programmable controller on the basis of the homogeneous processing element (PE) array and dynamic scheduling of PE array resources according to different application requirements. The proposed RMSRM is capable of feeding array execution state information to the programmable controller within 1 clock cycle, switching configurations between different tasks within 10 clock cycles, and shutting down the unnecessary PE/PEs according to the current configuration. To verify the correctness and efficiency, we model hardware with synthesizable RTL coding and implement it on FPGA and a chip. The experimental results show that RMSRM can effectively reduce the reconfiguration overhead compared with traditional reconfiguration methods. The volume of bits in the configuration file has decreased by an average of 39.37%, and the reconfiguration time has decreased by an average of 43.57%. Based on the SMIC 55nm process, the operating frequency can reach 320 MHz. Meanwhile, the resource consumption is 80506 logic gates, the chip area is 12 mm 2 , and the energy efficiency is 312 GOPS/W. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this study is to investigate the co-pyrolysis properties of epoxy resin and polyurethane, which are the main components of retired wind turbine blades. Methods: Pyrolysis experiments were carried out using TG/MS and Py-GC/MS techniques to reveal possible synergistic effects in the co-pyrolysis process. The key pyrolysis conditions such as pyrolysis temperature, raw material mixing ratio and ramp rate were investigated. Results: At a lower pyrolysis temperature of 500 °C and a higher heating rate of 10 °C/ms, the mixed pyrolysis of waste epoxy resin with polyurethane significantly promoted the formation of pyrolysis oil while inhibiting the formation of small molecule gaseous products. The kinetic results also showed that the synergistic effect between epoxy resin and polyurethane significantly reduced the apparent activation energy of the pyrolysis reaction, thus reducing the temperature required for complete pyrolysis of the feedstock. Conclusion: Based on the experimental results, reasonable pathways and synergistic mechanisms for the co-pyrolysis of epoxy resin and polyurethane are proposed. The present work contributes to the conversion of waste epoxy resin and polyurethane components into high quality pyrolysis oil, thus realizing clean disposal and resource utilization of wind turbine blade waste. [ABSTRACT FROM AUTHOR]

This paper presents a hybrid simplified grey wolf optimization algorithm combining with an modified pigeon inspired optimization algorithm. Firstly, a method of population initialization in the restricted area is designed to improve the average fitness of individuals. Then, a decay factor is designed to improve the search accuracy. At the same time, a new search position update formula is designed to balance the global search and local search ability, so as to improve the convergence speed of the algorithm. Furthermore, in order to verify the performance, the convergence, complexity and accuracy of the algorithm are analyzed by using linear difference equations. Finally, the comparison between different meta-heuristic optimization algorithms, the influence of parameters and their application in the path planning of unmanned aerial vehicle (UAV) are tested. Simulation results show that the proposed algorithm has stronger optimization ability and better robustness than those of compared algorithms. [ABSTRACT FROM AUTHOR]

We assess the associations between personality traits and co-occurrence of depressive symptoms and high BMI from adolescence to early adulthood. We employed a nationally representative cohort in China from 2010 to 2020 year. We included adolescents aged 10–19 years without depressive symptoms and unhealthy weight status (obesity, overweight, or thinness) at baseline and excluded those without any measurement of depressive symptoms or BMI at follow-ups. We assessed baseline personality traits in 7 dimensions of conscientiousness, openness, neuroticism, agreeableness, extraversion, self-esteem, and responsibility. We also assessed the combined effects of these 7 dimensions of personality traits by generating individual-level personality trait risk scores based on the weighted sum of all these 7 dimensions of personality traits. We measured the co-occurrence of depressive symptoms and high BMI using both a single measurement of depressive symptoms and BMI at the last follow-up and repeated measurements of them over 10 years. We used the multinomial logistic regression models to examine the exposure-outcome associations. At baseline, we included 1778 individuals (mean age: 14.4 year; female: 853 (48.0%)). At follow-ups, we observed increased risk of co-occurrence of depressive symptoms and high BMI per 1-SD increase in neuroticism score (1.95–2.38 odds ratio) or 1-SD decrease in self-esteem and conscientiousness (0.63–0.80 odds ratio; all P values < 0.05); we observed no evidence of associations between openness, agreeableness, extraversion, or responsibility and the risk of co-occurrence of depressive symptoms and high BMI (all P values > 0.05). For the combined effects of the 7 dimensions of personality traits, we found an elevated risk of co-occurrence of depressive symptoms and high BMI per 1-SD increase in the personality trait risk scores (OR (95% CI), single measurement at the last follow-up: 2.01, 1.66 to 2.43; trajectory classification using the repeated measurements 2.30, 1.55 to 3.42; average level using the repeated measurements: 2.27, 1.93 to 2.67). In this national cohort in China, personality traits were found to be associated with the co-occurrence of depressive symptoms and high BMI from adolescence to early adulthood. These findings highlight the importance of stratifying individuals based on their personality traits and providing targeted interventions for those at risk of comorbid depression and obesity. [ABSTRACT FROM AUTHOR]

This study discusses a finite-time tracking controller for a rehabilitative training walker that imposes velocity constraints. The walker was described using a stochastic model through which the rehabilitee mass can randomly change, and a velocity constraint method was proposed to control the velocity input to every omniwheel based on a model predictive algorithm. This approach is novel in that the velocity constraint information obtained from the kinematics model was used to design the tracking controller based on the stochastic dynamic model, thus successfully constraining the actual velocity of walker as per the stochastic system. The nonlinear tracking controller was built for the stochastic rehabilitative walker to make the system's finite time stable. Also, simulation and experiment were performed, and results confirmed that the proposed tracking control method with velocity constraints is very effective, so it may enable various rehabilitees to train safely. [ABSTRACT FROM AUTHOR]

The utilization of computation resources and reconfiguration time has a large impact on reconfiguration system performance. In order to promote the performance, a dynamical self-reconfigurable mechanism for data-driven cell array is proposed. Cells can be fired only when the needed data arrives, and cell array can be worked on two modes: fixed execution and reconfiguration. On reconfiguration mode, cell function and data flow direction are changed automatically at run time according to contexts. Simultaneously using an H-tree interconnection network, through pre-storing multiple application mapping contexts in reconfiguration buffer, multiple applications can execute concurrently and context switching time is the minimal. For verifying system performance, some algorithms are selected for mapping onto the proposed structure, and the amount of configuration contexts and execution time are recorded for statistical analysis. The results show that the proposed self-reconfigurable mechanism can reduce the number of contexts efficiently, and has a low computing time. [ABSTRACT FROM AUTHOR]

This paper proposes a novel model predictive control method with velocity estimation simultaneously constraining trajectory and velocity tracking errors for a cushion robot. The authors investigated a path planning method using improved particle swarm optimization (PSO) combined with Dijkstra's algorithm and obtained a real-time desired optimal motion path for obstacle avoidance. The authors designed a velocity observer to estimate the unmeasurable speed, while the asymptotic stability of the observer error system was established. A predictive controller with error-constrained performance was derived by solving a quadratic programming problem with incremental control. Simulation and experimental results confirm the effectiveness of the proposed method and verify that the error constraints adopted in the cushion robot provide safe motion while avoiding obstacles. [ABSTRACT FROM AUTHOR]

Zinc sulfide (ZnS) thin films have been prepared by chemical bath deposition followed by thermal annealing. The influence of sulphur (S) pressure on the morphological, structural and optical properties of the ZnS thin film has been investigated. The results show that the annealed ZnS thin films have more homogeneous morphology and better crystallinity compared with the as-deposited film. It was found that the crystallinity and mean grain size of ZnS films increase with the S pressure. Meanwhile, the transmittance of the film was significantly enhanced in the visible spectrum region with the increase of S vapor pressure, which may be attributed to the lower defects density of the film annealed at higher S vapor pressure. However, the optical band gap of ZnS thin films decrease with the increase of S pressure, which is associated with the larger grain size and higher crystallinity. The decreased band gap can adjust the conduction band offset of the buffer/absorber heterojunction in copper based semiconductor material (such as Cu(In,Ga)Se2, Cu(In,Ga)S2 or Cu2ZnSnS4)solar cell to a lower energy barrier to enhance the electron injection from absorber to ZnS buffer layer. According to the structural and optical properties analysis, the obtained ZnS thin films annealed at higher S pressure can potentially be used as better buffer layer of thin film solar cells. [ABSTRACT FROM AUTHOR]

The nature of dataflow computation demands the heavy flow of tokens amongst computation nodes. Traditional reduced instruction-set computer (RISC) processors are not suitable for such style computation. Devices that use long wire buses are not suitable for dataflow either. Reconfigurable computing devices (RCDs) consist of data transfer wires and computing resources. With minor modifications, reconfigurable cells can be adopted to perform dataflow computation. A reconfigurable cell array (RCA) is presented in this paper and it is suitable for dataflow computation. This cell array has a dynamic reconfigurable storage model. The distinctive features of the architecture include dataflow reconfigurable cells and reconfigurable storage. Dataflow applications can be mapped easily and effectively onto the cells. Reconfigurable storage is mainly used to manage data access and transmission. Furthermore, computation and data management are separated. Meanwhile, dynamical reconfiguration is accomplished, when some clusters of cells work in configuration mode and other clusters work in computation mode. The dataflow graphs of some algorithms are mapped onto our architecture, and the performance results are compared with those of CPU and GPU. [ABSTRACT FROM AUTHOR]

Transmitted ultrasonic wave simulation (TUWS) in a digital core is one of the important elements of digital rock physics and is used to study wave propagation in porous cores and calculate equivalent velocity. When simulating wave propagates in a 3D digital core, two additional layers are attached to its two surfaces vertical to the wave-direction and one planar wave source and two receiver-arrays are properly installed. After source excitation, the two receivers then record incident and transmitted waves of the digital rock. Wave propagating velocity, which is the velocity of the digital core, is computed by the picked peak-time difference between the two recorded waves. To evaluate the accuracy of TUWS, a digital core is fully saturated with gas, oil, and water to calculate the corresponding velocities. The velocities increase with decreasing wave frequencies in the simulation frequency band, and this is considered to be the result of scattering. When the pore fluids are varied from gas to oil and finally to water, the velocity-variation characteristics between the different frequencies are similar, thereby approximately following the variation law of velocities obtained from linear elastic statics simulation (LESS), although their absolute values are different. However, LESS has been widely used. The results of this paper show that the transmission ultrasonic simulation has high relative precision. [ABSTRACT FROM AUTHOR]

The problem of a hollow thick-wall cylinder subject to quadric function pressures is solved with a new stress function, thus laying the basis for solving the spatial symmetric deformation of a hollow cylinder subject to arbitrarily distributed pressures. [ABSTRACT FROM AUTHOR]

Heterogeneity of the Helicobacter pylori vacA gene may be associated with bacterial virulence and presentation. In this study, the possible correlation between vacA genotypes and gastric histopathology was investigated. Using a modified one-step polymerase chain reaction (PCR)-based method, 122 of 131 H. pylori isolates obtained from 63 of 67 patients from Germany were classified into distinct vacA genotypes according to their signal sequence (s1 or s2) and their midregion alleles (m1 or m2). A possible subtype of m1, now alluded to as m3, was identified in one-third of the isolates. Signal sequence s1 was significantly associated with higher H. pylori density but not with gastric inflammation parameters as compared with s2. Compared with m2, m1 initially appeared to correlate with higher mononuclear cell scores in corpus, although not with H. pylori density. Upon differentiation between m1 and m3, however, only the latter was associated with the high cell scores. Moreover, m3 also correlated with a higher antral H. pylori density. Positive cagA status correlated significantly with vacA signal sequence s1, and higher gastric mononuclear cell scores and corpus neutrophil score. H. pylori density was always associated with enhanced gastric neutrophil and corpus mononuclear cell scores. These data indicate a significant association of specific vacA genotypes with enhanced bacterial density and gastric inflammation. PCR-based identification of the respective alleles can now easily be performed in the diagnostic laboratory using a one-step PCR assay. [ABSTRACT FROM AUTHOR]