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With the rapid development of remote sensing image data, the efficient retrieval of target images of interest has become an important issue in various applications including computer vision and remote sensing. This research addressed the low-accuracy problem in traditional content-based image retrieval algorithms, which largely rely on comparing entire image features without capturing sufficient semantic information. We proposed a scene graph similarity-based remote sensing image retrieval algorithm. Firstly, a one-shot object detection algorithm was designed for remote sensing images based on Siamese networks and tailored to the objects of an unknown class in the query image. Secondly, a scene graph construction algorithm was developed, based on the objects and their attributes and spatial relationships. Several construction strategies were designed based on different relationships, including full connections, random connections, nearest connections, star connections, or ring connections. Thirdly, by making full use of edge features for scene graph feature extraction, a graph feature extraction network was established based on edge features. Fourthly, a neural tensor network-based similarity calculation algorithm was designed for graph feature vectors to obtain image retrieval results. Fifthly, a dataset named remote sensing images with scene graphs (RSSG) was built for testing, which contained 929 remote sensing images with their corresponding scene graphs generated by the developed construction strategies. Finally, through performance comparison experiments with remote sensing image retrieval algorithms AMFMN, MiLaN, and AHCL, in precision rates, Precision@1 improved by 10%, 7.2%, and 5.2%, Precision@5 improved by 3%, 5%, and 1.7%; and Precision@10 improved by 1.7%, 3%, and 0.6%. In recall rates, Recall@1 improved by 2.5%, 4.3%, and 1.3%; Recall@5 improved by 3.7%, 6.2%, and 2.1%; and Recall@10 improved by 4.4%, 7.7% and 1.6%.

Plasma technology is commonly used in numerous fields, such as microelectronics, nanomaterial synthesis, nitrogen fixation, biomedicine, environmental protection, and polymer surface modification [...]

In order to study the flight strategies of birds in shear wind and realize the long-range flight of an unmanned aerial vehicle (UAV), the aerodynamic performances of a UAV’s airfoil under different shear wind are studied using numerical methods. The results are calculated using the RANS method in shear wind with a linear and logarithmic distribution of velocity. The results show that the slope of the lift curve, the maximum lift coefficient and the stall angle decrease when the velocity gradient is positive or increasing, conversely, they increase at a negative gradient compared to gradient-free wind fields. A positive gradient of wind significantly increased the maximum lift-drag ratio and the effective angle of attack. Compared with linear distributed shear wind with the same velocity at both the lowest and highest points of the flow field, logarithmic distribution decreases the slope of the lift curve, the maximum lift coefficient and the maximum lift-drag ratio and the effective angle of attack. Therefore, a shear wind with a positive gradient is beneficial to the increase of lift-drag ratio and more conducive to cruise flight, and a negative gradient is beneficial for increased lift and more conducive to take-off and landing of UAVs. The velocity distributions influence the aerodynamic performances of the airfoil which is related to the speed and gradient distribution of shear wind.

Plasma-activated tap water (PATW) is a new technology for obtaining a high concentration of active aqueous plasma substances by discharging underwater. Commonly plasma-activated water (PAW) is realized by activating deionized water or distilled water, which has problems such as high cost, a small discharge area, and insufficient dissolution of active substances. This paper reports the development of a dielectric barrier discharge array to generate a high concentration of active aqueous plasma substances. The device can realize a uniform, stable, and large-area discharge in a large volume of tap water, and it has the advantages of low cost, high integration, and reusability. Using the device to treat 1000 mL of tap water for 1 h can reduce the pH of the tap water from 8.10 to 2.54, and the logarithmic value of killing E. coli is greater than 5.0. We sprayed PATW onto clothes to sterilize the bacteria when people were through the disinfection door and verified that the PATW had a good sterilization effect. The short-lived substances, singlet oxygen, and superoxide anion radicals played a key role in the sterilization process by PATW.

Artificial intelligence (AI) systems are becoming wiser, even surpassing human performances in some fields, such as image classification, chess, and Go. However, most high-performance AI systems, such as deep learning models, are black boxes (i.e., only system inputs and outputs are visible, but the internal mechanisms are unknown) and, thus, are notably challenging to understand. Thereby a system with better explainability is needed to help humans understand AI. This paper proposes a dual-track AI approach that uses reinforcement learning to supplement fine-grained deep learning-based sentiment classification. Through lifelong machine learning, the dual-track approach can gradually become wiser and realize high performance (while keeping outstanding explainability). The extensive experimental results show that the proposed dual-track approach can provide reasonable fine-grained sentiment analyses to product reviews and remarkably achieve a 133% promotion of the Macro-F1 score on the Twitter sentiment classification task and a 27.12% promotion of the Macro-F1 score on an Amazon iPhone 11 sentiment classification task, respectively.

Lossy dielectric bars have potential applications in high power microwave (HPM) radiation-effect experiments performed in wind tunnels. Under plane excitation, beat wave patterns are observed along lossy and lossless dielectric bars in 3-D electromagnetic simulation results. Mode analysis is performed to clarify the two main modes in the beat waves—the leaky and guided modes. Comparisons are made between the theoretical and simulated results and acceptable agreements are obtained. The absorbing array of lossy dielectric bars is further investigated. The array can attenuate 90% of the microwave power at 10 GHz when a ten-meter series of such arrays is arranged. It is expected that the proposed absorbing array can achieve the required attenuation, considering that the testing object under microwave radiation is also an absorbing structure itself.

Storage is a promising application for permission-less blockchains. Before blockchain, cloud storage was hosted by a trusted service provider. The centralized system controls the permission of the data access. In web3, users own their data. Data must be encrypted in a permission-less decentralized storage network, and the permission control should be pure cryptographic. Proxy re-encryption (PRE) is ideal for cryptographic access control, which allows a proxy to transfer Alice’s ciphertext to Bob with Alice’s authorization. The encrypted data are stored in several copies for redundancy in a permission-less decentralized storage network. The redundancy suffers from the outsourcing attack. The malicious resource provider may fetch the content from others and respond to the verifiers. This harms data integrity security. Thus, proof-of-replication (PoRep) must be applied to convince the user that the storage provider is using dedicated storage. PoRep is an expensive operation that encodes the original content into a replication. Existing PRE schemes cannot satisfy PoRep, as the cryptographic permission granting generates an extra ciphertext. A new ciphertext would result in several expensive replication operations. We searched most of the PRE schemes for the combination of the cryptographic methods to avoid transforming the ciphertext. Therefore, we propose a new PRE scheme. The proposed scheme does not require the proxy to transfer the ciphertext into a new one. It reduces the computation and operation time when allowing a new user to access a file. Furthermore, the PRE scheme is CCA (chosen-ciphertext attack) security and only needs one key pair.

Improving the transdermal delivery efficiency of medicine is a crucial measure to improve the treatment efficiency of psoriasis. This paper developed a low-cost, highly active, and large-action-area low-temperature plasma (LTP) jet array. The two components of plasma—the high concentration of reactive oxygen and nitrogen species and the strong electric field—easily changed the structural integrity of the stratum corneum, which enhanced the transdermal delivery of the medicine. Tripterygium wilfordii Hook F (TwHF) is a medicine used to treat autoimmune and inflammatory conditions. The enhanced transdermal delivery of TwHF significantly alleviated the severed psoriasiform dermatitis induced by the imiquimod. Unlike the TwHF treatment alone, the LTP + TwHF treatment was more efficient at suppressing epidermal thickening and inhibiting systemic inflammation without noticeable side effects. LTP + TwHF treatment provides a potential new solution for psoriasis treatment.

Lightweight design is one of the important ways to reduce automobile fuel consumption and exhaust emissions. At the same time, the fatigue life of automobile parts also greatly affects vehicle safety. This paper proposes a multi-objective reliability optimization method by integrating Monte Carlo simulation (MCS) with the NSGA-II algorithm coupled with entropy weighted grey relational analysis (GRA) for lightweight design of the lower control arm of automobile Macpherson suspension. The dynamic load histories of the control arm were extracted through dynamic simulations of a rigid-flexible coupling vehicle model on virtual proving ground. Then, the nominal stress method was used to predict its fatigue life. Six design variables were defined to describe the geometric dimension of the control arm, while mass and fatigue life were taken as optimization objectives. The multi-objective optimization design of the control arm was carried out based on the Kriging surrogate model and NSGA-II algorithm. Aiming at the uncertainty of design variables, the reliability constraint was added to the multi-objective optimization to improve the reliability of the fatigue life of the control arm. The optimal design of the control arm was determined from Pareto solutions by entropy weighted grey relational analysis (GRA). The optimization results show that the mass of the control arm was reduced by 4.1% and the fatigue life was increased by 215.8% while its reliability increased by 7.8%. The proposed multi-objective reliability optimization method proved to be feasible and effective for lightweight design of a suspension control arm.

A special V-shaped support for blended wing body aircraft was designed and applied in high-speed wind tunnel tests. In order to reduce the support interference and explore the design criteria of the V-shaped support, interference characteristics and geometric parameter effects of V-shaped support on blended wing body aircraft were numerically studied. According to the numerical results, the corresponding dummy V-shaped supports were designed and manufactured, and verification tests was conducted in a 2.4 m × 2.4 m transonic wind tunnel. The test results were in good agreement with the numerical simulation. Results indicated that pitching moment of blended wing body aircraft is quite sensitive to the V-shaped support geometric parameters, and the influence of the inflection angle is the most serious. To minimize the pitching moment interference, the straight-section diameter and inflection angle should be increased while the straight-section length should be shortened. The results could be used to design special V-shaped support for blended wing body aircraft in wind tunnel tests, reduce support interference, and improve the accuracy of test results.

Enzyme assisted extraction was used to extract the polysaccharides from pumpkin seeds (PSP) and the extraction parameters were optimized by response surface methodology (RSM). Under the optimum experimental parameters: Extraction temperature of 60 °C, extraction time of 43 min, enzyme concentration of 2.5%, and pH of 6.0, the yield of PSP was 3.22 ± 0.04%, which was in close agreement with the predicted value (3.24%). After further purification on anion exchange column and gelfiltration column, a novel purified polysaccharide (PSPE) with molecular weight of 16,700 g/mol was obtained. PSPE was mainly composed of mannose, galactose and glucose in the molar ratio of 1.00:3.84:1.62. NMR spectra analysis showed that the major backbone of PSPE consisted of →4)-α-d-Glcp-(1→, →4)-β-d-Manp-(1→, →3,6)-β-d-Glap-(1→, and β-d-galactose.