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This paper constructs a network security intelligence analysis model based on deep learning methods. Firstly, the weights and thresholds of network packets are modeled using the convolutional neural network algorithm to extract the main information features. Then, the backward propagation algorithm is used for layer-by-layer propagation, combined with an unsupervised autoencoder to achieve the network parameter update. The results show that the model can recognize a variety of network viruses, with an average detection rate of 97%, and the error rate is kept around 0.5%. The network security intelligence analysis model is based on the deep learning method to analyze and warn about network intrusion data, effectively improving college students’ awareness about network security.

Low-temperature plasma ablation has been recently used for minimally invasive surgeries. However, more research is still needed on its generation process during tissue ablation and the underlying mechanism of tissue thermal damage. In this paper, high-speed camera footage, voltage–current signal collection, temperature analysis, and histological analysis were used to investigate the dynamic process of plasma tissue ablation and its thermal effect of dual-needle electrodes immersed in normal saline, which were driven by a high-frequency DC power supply with an output voltage ranging from 220 V to 320 V and a squire wave of 100 kHz. Microbubbles occurred around the ground electrode and merged to form a vapor layer that could completely cover the ground electrode. Plasma capable of ablating tissue would occur in the vapor layer between the ground electrode and tissue. The effect of electrical parameters on plasma generation and its thermal effect are analyzed by statistical results. The experimental results indicated that the voltage applied to the electrodes significantly influenced both the generation and stability of plasma, as well as the heat generation and tissue damage around the electrodes. Furthermore, under the same voltage, the existence of biological tissue promotes the formation of a vapor layer around the electrode, thereby facilitating the generation and stability of plasma. Notably, the temperature rise around the ground electrode is much higher than that around the powered electrode. These results have direct application to the design of plasma tissue ablation systems, which could achieve tissue ablation effects with minimal thermal damage. [ABSTRACT FROM AUTHOR]

The mechanical properties of the stent graft are important factors influencing the outcome of TEVAR treatment and the occurrence of postoperative complications. The aim of this study is to improve and design a mechanical performance testing equipment for thoracic aortic stent grafts. The mechanical performance testing equipment consists of a radial force testing equipment of the stent graft designed by the wire compression grip method and a dynamic straightening force testing device with stable and controllable test conditions and continuously variable test angles. By constructing the testing equipment to physically measure the stent specimen, the experimental results reflect the trend of change and the simulation results are basically consistent, i.e. the mechanical properties of the thoracic aortic stent designed in this study is feasible and the measured data are valid. The testing equipment can provide the basis and reference direction for the quality testing of stent graft products, optimisation of mechanical properties of stent grafts and R&D innovation. [ABSTRACT FROM AUTHOR]

This study aimed to design a novel electrode for reducing tissue thermal damage in radiofrequency-induced intestinal anastomosis. We developed and compared two electrodes (Ring electrode, and Plum electrode with reduced section of the middle fusion area by nearly 80% arising from novel structural design) by performing ex-vivo experiments and finite element analysis. In contrast to the Ring electrode group, slightly higher mean strength is acquired with the tensile force and burst pressure results increasing from 9.7 ± 1.47 N, 84.0 ± 5.99 mmHg to 11.1 ± 1.71 N, 89.4 ± 6.60 mmHg, respectively, as well as a significant reduction in tissue thermal damage for the Plum electrode group, with compression pressure of 20 kPa, RF energy of 120 W and welding duration of 8 s applied to the target regions to achieve anastomosis. Besides, the novel structural design of the Plum electrode can counteract the tension generated by intestinal peristalsis and enhance the biomechanical strength of the anastomotic area. The histological observation showed that the fusion area of the two-layer intestinal tissue is tightly connected with decreased thickness. The novel electrode (Plum electrode) could reduce tissue thermal damage in radiofrequency-induced intestinal anastomosis. [ABSTRACT FROM AUTHOR]

For decades, radiofrequency (RF)-induced tissue fusion has garnered great attention due to its potential to replace sutures and staples for anastomosis of tissue reconstruction. However, the complexities of achieving high bonding strength and reducing excessive thermal damage present substantial limitations of existing fusion devices. This study proposed a discrete linkage-type electrode to carry out ex vivo RF-induced intestinal anastomosis experiments. The anastomotic strength was examined by burst pressure and shear strength test. The degree of thermal damage was monitored through an infrared thermal imager. And the anastomotic stoma fused by the electrode was further investigated through histopathological and ultrastructural observation. The burst pressure and shear strength of anastomotic tissue can reach 62.2 ± 3.08 mmHg and 8.73 ± 1.11N, respectively, when the pressure, power and duration are 995 kPa, 160 W and 13 s, and the thermal damage can be controlled within limits. Histopathological and ultrastructural observation indicate that an intact and fully fused stomas with collagenic crosslink can be formed. The discrete linkage-type electrode presents favorable efficiency and security in RF-induced tissue fusion, and these results are informative to the design of electrosurgical medical devices with controllable pressure and energy delivery. [ABSTRACT FROM AUTHOR]

The flexible transmission structure have more and more applications in minimally invasive surgical instrument. Due to the complexity of the structure,it is often difficult to calculate the mechanical property by the theoretical analysis of the structure. A double helix flexible transmission structure is proposed and the finite element model of the double helix structure is established in software ABAQUS and the influence of geometrical parameters on torsion stiffness of the double helix structure is analyzed,such as diameter,pitch,wall thickness and bottom radius. The results indicated that with the increase of nuclear diameter,pitch,thickness and bottom radius,the torsional stiffness increases,and with other parameters unchanged,the torsional stiffness and thickness are linear relationship,which has importance guiding significance for the design of the double helix structure.

At present, most searchable encryption focuses on text search, aiming at how to search graphics in cloud computing, a new privacy preserving searchable encryption scheme under public key system is proposed. Through a new similarity judgment technique, the characteristic information of graphic shape is transformed into single keyword encryption, and the graphic shape searchable encryption (GSSE) is realized by using the public key authentication encryption with keyword searchable (PAEKS), which realizes the function of protecting the privacy of users and data, and the fixed size ciphertext and trapdoor are achieved. Finally, under the random oracle model, it is proved that the scheme proposed in this paper has the semantic security of external selection multi-keyword attack and internal keyword guessing attack. Finally, under the random oracle model, the semantic security of external selection multi- keyword attack and internal keyword guessing attack of the scheme is proved. The experimental results show that the scheme has high efficiency. [ABSTRACT FROM AUTHOR]