To optimize Text-to-SQL generation performance based on heterogeneous graph encoder, SELSQL model was proposed. Firstly, an end-to-end learning framework was employed by the model, and the Poincaré distance metric in hyperbolic space was used instead of the Euclidean distance metric to optimize semantically enhanced schema linking graph constructed by the pre-trained language model using probe technology. Secondly, K-head weighted cosine similarity and graph regularization method were used to learn the similarity metric graph so that the initial schema linking graph was iteratively optimized during training. Finally, the improved Relational Graph ATtention network (RGAT) graph encoder and multi-head attention mechanism were used to encode the joint semantic schema linking graphs of the two modules, and Structured Query Language (SQL) statement decoding was solved using a grammar-based neural semantic decoder and a predefined structured language. Experimental results on Spider dataset show that when using ELECTRA-large pre-training model, the accuracy of SELSQL model is increased by 2.5 percentage points compared with the best baseline model, which has a great improvement effect on the generation of complex SQL statements.
Aiming at the difference of health system resilience in urban areas and the random evolution of demand for emergency medical supplies, a multi-stage dynamic allocation model for emergency medical supplies based on resilience assessment was proposed. Firstly, combined with the entropy method and the K-means algorithm, the resilience assessment system and classification method of area’s health system were established. Secondly, the random evolution characteristic of demand state was designed as a Markov process, and triangular fuzzy numbers were used to deal with the fuzzy demand, thereby constructing a multi-stage dynamic allocation model of emergency medical supplies. Finally, the proposed model was solved by the binary Artificial Bee Colony (ABC) algorithm, and the effectiveness of the model was analyzed and verified by an actual example. Experimental results show that the proposed model can realize the dynamic allocation of supplies to stabilize the demand changes and prioritize the allocation of areas with weak resilience, reflecting the fairness and efficiency of emergency management requirements.
The existing image super-resolution reconstruction methods are affected by texture distortion and details blurring of generated images. To address these problems, a new image super-resolution reconstruction network based on multi-channel attention mechanism was proposed. Firstly, in the texture extraction module of the proposed network, a multi-channel attention mechanism was designed to realize the cross-channel information interaction by combining one-dimensional convolution, thereby achieving the purpose of paying attention to important feature information. Then, in the texture recovery module of the proposed network, the dense residual blocks were introduced to recover part of high-frequency texture details as many as possible to improve the performance of model and generate high-quality reconstructed images. The proposed network is able to improve visual effects of reconstructed images effectively. Besides, the results on benchmark dataset CUFED5 show that the proposed network has achieved the 1.76 dB and 0.062 higher in Peak Signal-to-Noise Ratio (PSNR) and Structural SIMilarity (SSIM) compared with the classic Super-Resolution using Convolutional Neural Network (SRCNN) method. Experimental results show that the proposed network can increase the accuracy of texture migration, and effectively improve the quality of generated images.
Before an emergency occurs, the hospitals need to maintain a certain amount of emergency resource redundancy. Aiming at the problem of configuration optimization of hospital emergency resource redundancy under emergencies, firstly, based on the utility theory, by analyzing the utility performance of the hospital emergency resource redundancy, the emergency resource redundancy was defined and classified, and the utility function conforming to the marginal law was determined. Secondly, the redundancy configuration model of hospital emergency resources with maximal total utility was established, and the upper limit of emergency resource storage and the lower limit of emergency rationality were given as the constraints of the model. Finally, the combination of particle swarm optimization and sequential quadratic programming method was used to solve the model. Through case analysis, four optimization schemes for the emergency resource redundancy of the hospital were obtained, and the demand degree of the hospital emergency level to the hospital emergency resource redundancy was summarized. The research shows that with the emergency resource redundancy configuration optimization model, the emergency rescue of hospitals under emergencies can be carried out well, and the utilization efficiency of hospital emergency resources can be improved.
To solve the problem that high dimension of descriptor decreases the matching speed of Scale Invariant Feature Transform (SIFT) algorithm, an improved SIFT algorithm was proposed. The feature point was acted as the center, the circular rotation invariance structure was used to construct feature descriptor in the approximate size circular feature points' neighborhood, which was divided into several sub-rings. In each sub-ring, the pixel information was to maintain a relatively constant and positions changed only. The accumulated value of the gradient within each ring element was sorted to generate the feature vector descriptor when the image was rotated. The dimensions and complexity of the algorithm was reduced and the dimensions of feature descriptor were reduced from 128 to 48. The experimental results show that, the improved algorithm can improve rotating registration repetition rate to more than 85%. Compared with the SIFT algorithm, the average matching registration rate increases by 5%, the average time of image registration reduces by about 30% in the image rotation, zoom and illumination change cases. The improved SIFT algorithm is effective.
In order to decrease the influence caused by low bandwidth and high latency on Media Access Control (MAC) layer in Underwater Acoustic Sensor Network (UWASN), an Evolutionary Game Theory based MAC (EGT-MAC) protocol was proposed. In EGT-MAC, each sensor node adopted two strategies including spatial multiplexing and temporal multiplexing. With the replication kinetics equation, each strategy got an evolutionary stable strategy and reached stable equilibrium of evolution. In this way, it improved channel utilization rate and data transmission efficiency to achieve performance optimization for MAC protocol. The simulation results show that EGT-MAC can improve the network throughput as well as the transmission rate of data packet.