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This study proposes a new deep neural network to solve the multi-band image synchronous fusion problem (MBF-Net). Unlike other deep learning-based methods, our network architecture design combines the ideas of model-driven and data-driven methods, so it is more interpretable. First, a new multi-band image synchronous fusion model is proposed. The source image in the data fidelity terms and the prior regularization are implicitly represented by the deep learning network and jointly learned from the training data. The proposed model is then solved using a half quadratic splitting (HQS) algorithm and unfolded into a deep fusion network. In addition, a new saliency loss function is proposed to retain thermal radiation information to enhance the fusion effect. Finally, the experimental results on the TNO dataset demonstrated the effectiveness of the proposed MBF-Net.

Using electronic devices at night can easily cause visual fatigue. We investigated the conjoint effects of color mode and luminance contrast on visual fatigue and subjective preference when using electronic devices under low screen luminance and low ambient illumination at night. A multidimensional approach based on eye and subjective measures was used to test 2 color modes (dark mode, light mode) and 6 luminance contrast ratios (0.969, 0.935, 0.868, 0.855, 0.725, 0.469) in a 2 × 6 experimental design. We used eye movement tracking technology to collect blink rate and pupil diameters, and used the Likert scale to measure subjective visual fatigue scale and preference. Results showed that reading in the dark mode reduced visual fatigue, as reflected by an increase in blink rate and pupil accommodation. Lower subjective visual fatigue scale and higher preference were found in the light mode due to subjects' using habits of dark texts on a light background. There was a significant negative correlation between (text-background) luminance contrast and visual fatigue, and subjects preferred higher luminance contrast. We observed the lowest visual fatigue under the luminance contrast of 0.969 in the dark mode, and the lowest subjective preference when the luminance contrast was lower than 0.725. We suggest the users should choose the dark mode to reduce visual fatigue when using electronic devices at night. These findings also provide a reference for the design of interactive interfaces such as tablets and mobile phones, and have practical implications for reducing visual fatigue.

While the COIVD-19 has triggered the rapid and large-scale promotion of online courses, it has also exposed the problem of poor user experience on online course platforms. Therefore, this research hopes to propose a complete user experience evaluation system to clarify the deficiencies of the platform and give directions for improvement. This research combines qualitative and quantitative, from the perspective of user experience, integrates data obtained through literature research, interview and network research to determine evaluation indices. The Delphi method and analytic hierarchy process are used to determine the weights of various indices and set the scoring level. It is obtained that the “ease of operation” has the most important impact on the user experience of the online live course platform. Innovatively adopting the t-test method to establish a comparative analysis method for the model application, a standardized process of model application is designed, and a complete evaluation system is constructed. Two pieces of software are selected as experimental samples to verify the model from both statistics and practical applications. The test results show that although the two experimental sample software have significant differences in the scores of multiple second-level indices, the overall scores are still similar, which is consistent with the direct evaluation results. Therefore, the user experience evaluation system proposed in this research is reliable, which can provide a reference for the construction of online live course platform and the optimization of user experience.

Model predictive control (MPC) has been successfully applied in practical wind tunnel systems. As a critical component of MPC, the accurate prediction of Mach number becomes hence very significant. Real measurement data records often contain outliers or noisy data because of the harsh working conditions of practical systems. Such datasets are detrimental to most data-driven Mach number predictors. This paper focuses on improving Mach number prediction via a regression-based outlier detection framework. The development of a regression-based outlier detector for enhancing Mach number prediction is natural since only regression analysis needs to be implemented for both prediction and outlier detection. In contrast to existing regression-based detectors, we have taken into account three problems that may greatly impact the detecting performance. Specifically, we use Bagging technique to reduce the negative influence of unknown outliers during the training phase. Then, the notion of extreme value analysis is used to determine an appropriate threshold for the calculated outlier scores. A robust scaling method based on Hampel identifier is also used to alleviate the influence of outliers on data scaling. Several datasets stemming from a real-world wind tunnel are used in experiments to verify the effectiveness of our detector. The experimental results show that regression-based outlier detectors often perform better if the prior knowledge about the dependent variable is used. In addition, the proposed detector has outperformed other regression-based detectors.

In China, a structure in which multiple line-commutated converter based high-voltage direct current (LCC-HVDC) systems feed into the same AC system has been formed. For the multiple LCC-HVDC infeed system, the electrical strength and real operating condition evaluation of the receiving AC system are of great significance for system operation. The multi-infeed short circuit ratio (MISCR) is generally utilized to assess the strength based on the rated parameters; hence, it cannot analyze the real operating condition under the non-rated status. In this paper, an LCC-HVDC system is equivalent to a grounded impedance without changing the external characteristics. The multi-infeed operating short circuit ratio (MIOSCR) is then deduced from the equivalent impedance and equivalent nodal analysis. Relationships between the MIOSCR and electrical strength indices of AC and AC/DC systems are analyzed, and the MISCR is deduced as a special case of the MIOSCR under the rated status. The multi-infeed operating margin coefficient (MIOMC) is finally proposed, which can be utilized to evaluate the operating margin of the LCC-HVDC system and provide guidance for designing operating strategies. The proposed MIOSCR and MIOMC overcome the previous shortcomings of inaccuracy about operating status assessment by the MISCR. The results of the case study demonstrate the effectiveness of the MIOSCR and the MIOMC for assessing the operating condition and margin of converter buses.

The problems of CNC machine tool (CNCMT) fault diagnosis and production rescheduling have attracted continuous attention because of their great significance to the manufacturing industry. Digital twin is a supporting technology for achieving smart manufacturing and provides a new paradigm for solving these problems. This paper explores a digital twin-driven interaction and cooperation framework and proposes the architecture and implementation mechanism to enable the sharing of data, knowledge, and resource, to realize the fusion of physical space and cyber space, and to improve the accuracy of fault diagnosis. Under this framework, aiming at the influence of CNCMT failure on the initial production planning, a self-adaptation rescheduling method based on Monte Carlo Tree Search (MCTS) algorithm is proposed to provide support for developing more efficient production planning. Finally, the effectiveness of the proposed framework is validated by experimental study. The framework and integrated rescheduling approach can provide guidance for enterprises in implementing CNCMT maintenance and production scheduling to meet high accuracy and reliability requirements.

Perovskite quantum dots (QDs) attracted a lot of attention recently due to their high light conversion efficiency, and high color purity. However, perovskite materials are sensitive to heat. High temperature will cause serious quenching problem of the perovskite QDs. In order to solve the QDs thermal quenching problem without destroying their optical characters. A circulating quantum dots colloidal solution converter (CQD-converter) was developed. A closed loop pump tube coated with Teflon was utilized to prevent perovskite QDs from the external environment. A peristaltic pump was utilized to drive the QDs colloidal solution through a Peltier cooler for dissipating the heat of the QDs colloidal solution. The lifetime of the perovskite QDs can be significantly improved under a 450nm laser excitation. The effects of temperature of the Peltier cooler and flow velocity on the optical properties of QDs were also investigated. Compared to the static quantum dots colloidal solution (SQD-converter), which quenched after 7 min, the optical properties were maintained after 600 min for the CQD-converter.

Generally, it is not easy to construct quantum maximal-distance-separable (MDS) codes with the minimum distance greater than $\frac {q}{2}+1$ . The minimum distance of quantum MDS codes can achieve $\frac {q}{2}+1$ or exceed $\frac {q}{2}+1$ by adopting pre-shared entanglement. In this work, some new families of entanglement-assisted quantum MDS codes that satisfy the quantum Singleton bound are constructed and the number of maximally entangled states required is determined to make the minimum distance of some constructed codes achieve $\frac {q}{2}+1$ or exceed $\frac {q}{2}+1$ by utilizing the decomposition of the defining set and $q^{2}$ -cyclotomic cosets of constacyclic codes with length $\frac {q^{2}+1}{\gamma }$ , where $\gamma =t^{2}+1$ , $t$ is a power of 2 and $q=t^{e}>4$ with $e\equiv 1~\textrm {mod}~4$ or $e\equiv 3~\textrm {mod}~4$ . Moreover, the parameters of these codes constructed in this paper are more general relative to the ones in the literature and the minimum distance of some codes constructed in this paper is larger than $\frac {q}{2}+1$ .