Telemedicine network latency management system in 5G telesurgery: a feasibility and effectiveness study.

BACKGROUND: Network latency is the most important factor affecting the performance of telemedicine. The aim of the study is to assess the feasibility and efficacy of a novel network latency management system in 5G telesurgery. METHODS: We conducted 20 telesurgery simulation trials (hitching rings to columns) and 15 remote adrenalectomy procedures in the 5G network environment. Telemedicine Network Latency Management System and the traditional "Ping command" method (gold standard) were used to monitor network latency during preoperative simulated telesurgery and formal telesurgery. We observed the working status of the Telemedicine Network Latency Management System and calculated the difference between the network latency data and packet loss rate detected by the two methods. In addition, due to the lower latency of the 5G network, we tested the alert function of the system using the 4G network with relatively high network latency. RESULTS: The Telemedicine Network Latency Management System showed no instability during telesurgery simulation trials and formal telesurgery. After 20 telesurgery simulation trials and 15 remote adrenalectomy procedures, the p-value for the difference between the network latency data monitored by the Telemedicine Network Latency Management System and the "Ping command" method was greater than 0.05 in each case. Meanwhile, the surgeons reported that the Telemedicine Network Latency Management System had a friendly interface and was easy to operate. Besides, when the network latency exceeded a set threshold, a rapid alarm sounded in the system. CONCLUSION: The Telemedicine Network Latency Management System was simple and easy to operate, and it was feasible and effective to use it to monitor network latency in telesurgery. The system had an intuitive and concise interface, and its alarm function increased the safety of telesurgery. The system's own multidimensional working ability and information storage capacity will be more suitable for telemedicine work.

Experimental investigation of seismic response of precast concrete panels with castellated keys support pillar connections under in-plane cyclic loading.

The reliable joint connection between precast members is vital to resisting earthquake loads in precast concrete structures. To further improve the convenience of precast construction, this paper presents a new horizontal joint of precast concrete panels with castellated keys supports pillar connections based on the stable mechanical properties of the wet concrete joint. To examine the seismic response of this connection type, a series of in-plane cyclic loading tests were carried out using six full-size precast specimens and one cast-in-place specimen for comparison. The influences of axial compression ratio, joint width, and joint concrete strength on the seismic indicators of the precast concrete panel were considered in the design of specimens. The test results showed all specimens had the same damage process, and the ultimate failure modes combined compression and bending. The precast specimens exhibited similar seismic performance to the cast-in-place specimen, especially whose joint concrete strength is higher than the precast concrete panel. Based on the load-displacement test curve, a hysteretic curve model that included both the envelope curve and the stiffness degradation law was proposed. The predictions from the model showed good compatibility with the experimental results, and the model can be used as a reference for analyzing the elastic-plastic response of the precast concrete panels with castellated keys supporting pillar connections.

Clean visual field reconstruction in robot-assisted laparoscopic surgery based on dynamic prediction.

Robot-assisted minimally invasive surgery has been broadly employed in complicated operations. However, the multiple surgical instruments may occupy a large amount of visual space in complex operations performed in narrow spaces, which affects the surgeon's judgment on the shape and position of the lesion as well as the course of its adjacent vessels/lacunae. In this paper, a surgical scene reconstruction method is proposed, which involves the tracking and removal of surgical instruments and the dynamic prediction of the obscured region. For tracking and segmentation of instruments, the image sequences are preprocessed by a modified U-Net architecture composed of a pre-trained ResNet101 encoder and a redesigned decoder. Also, the segmentation boundaries of the instrument shafts are extended using image filtering and a real-time index mask algorithm to achieve precise localization of the obscured elements. For predicting the deformation of soft tissues, a soft tissue deformation prediction algorithm is proposed based on dense optical flow gravitational field and entropy increase, which can achieve local dynamic visualization of the surgical scene by integrating image morphological operations. Finally, the preliminary experiments and the pre-clinical evaluation were presented to demonstrate the performance of the proposed method. The results show that the proposed method can provide the surgeon with a clean and comprehensive surgical scene, reconstruct the course of important vessels/lacunae, and avoid inadvertent injuries.

Design and experiment of a 3-DoF master device with a 2-DoF parallel mechanism for flexible ureteroscopy.

BACKGROUND: Traditional commercial master devices and specialied serial master devices meet insufficient workspace, low intuitiveness, low stiffness, and poor accuracy during master-slave mapping for robot-assisted flexible ureteroscopy (FURS). METHODS: This paper presents a 3-DoF master device for FURS. A 2-DoF parallel mechanism was designed and utilised in the master device for higher stiffness based on requirements analysis. A Back Propagation Neural Network was built for the forward kinematics of the parallel mechanism during master-slave mapping. Analysis of mechanical characteristics was carried out for the usability of the master device. A contrast experiment on the phantom was conducted to evaluate the performance between the proposed master device and a previous one. RESULTS: The completion time for each trial of the proposed master devices is shorter than that of the previous master serial device. Meanwhile, the proposed device provides a more comfortable operating style than the previous one. CONCLUSIONS: The proposed 3-DoF configuration for the master device is with more intuitive performance. A better comfort level indicates its usability in clinical applications.

Design and Performance Investigation of a Robot-Assisted Flexible Ureteroscopy System.

Flexible ureteroscopy (FURS) has been developed and has become a preferred routine procedure for both diagnosis and treatment of kidney stones and other renal diseases inside the urinary tract. The traditional manual FURS procedure is highly skill-demanding and easily brings about physical fatigue and burnout for surgeons. The improper operational ergonomics and fragile instruments also hinder its further development and patient safety enhancement. A robotic system is presented in this paper to assist the FURS procedure. The system with a master-slave configuration is designed based on the requirement analysis in manual operation. A joint-to-joint mapping strategy and several control strategies are built to realize intuitive and safe operations. Both phantom and animal experiments validate that the robot has significant advantages over manual operations, including the easy-to-use manner, reduced intraoperative time, and improved surgical ergonomics. The proposed robotic system can solve the major drawbacks of manual FURS. The test results demonstrate that the robot has great potential for clinical applications.

[Establishment and Application of Performance Evaluation and Obstacle Diagnosis Model for Regional Water Ecological Civilization Construction].

A scientific performance evaluation of the regional water ecological civilization construction and clarifying the obstacle factor are key points to improve the performance of regional water ecological civilization construction theory. This study analyzes the coupling relationship between humans and regional water ecology by applying the thinking logic of "driving force-pressure-state-influence-response-management." The regional water ecological civilization construction performance evaluation index system based on the DPSIRM model was established. Combining the unascertained measurement model and obstacle diagnosis model, the water ecological civilization construction performance of Shizuishan City during the past 10 years was empirically evaluated, and the obstacle factors affecting local construction performance were diagnosed and analyzed. The analytical results reveal the following points:First, the performance of the water ecological civilization construction in Shizuishan City gradually increased annually and revealed three development stages:the site visit and slow improvement (2010-2014), intermediate but fast improvement (2015-2017) and good and fast improvement (2018-2019). Second, each subsystem performance index trend varied, but generally, the fluctuations rose. Third, from 2010 to 2014, the average obstacle degree of the subsystem state, subsystem response, and subsystem pressure reached 58.81%, which became the main obstacles restricting the performance of the local water ecological civilization construction. From 2015 to 2017, the average pressure barrier degree reached 21.73%, which was the most significant obstacle to the construction performance. From 2018 to 2019, the average pressure barrier degree remained the largest obstacle by reaching 24.49%. Lastly, the index barrier of the obstacle degree among the top five factors are primarily distributed in the pressure subsystem. A comprehensive frequency ranking of the obstacles, the irrigation water use coefficient, and the pressure of the water consumption per ten thousand yuan of value-added by industry as a representative subsystem are the key directions to future construction. In this paper, the concepts and methods of the research can provide a theoretical reference for the performance evaluation of regional water ecological civilization construction and its obstacle factor diagnosis analysis.

Fabrication of new conductive surface-metallized UHMWPE fabric with improved thermal resistance.

A new UHMWPE-based conductive fabric was successfully prepared by radiation-induced graft polymerization and subsequent post-modification, followed by electroless deposition. The chemical structure and composition of modified UHMWPE fabrics were investigated in detail by ATR-FTIR, 29Si NMR, and XPS to confirm grafting and post-modification. After electroless deposition, the morphology, thermal stability, and crystal structure of original and modified fabrics were characterized by SEM, TG, DSC and XRD. Cu-deposited UHMWPE fabric exhibited much better thermal resistance than that of UHMWPE and Cu@UHMWPE-g-PAAc. In order to improve the oxidation resistance of copper-deposited fabric, nickel was processed on copper-coated UHMWPE fabric to protect the copper layer. An electromagnetic shielding effect test showed the nickel-copper coated UHMWPE fabric could shield 94.5% of the electromagnetic wave in the frequency range of 8-12 GHz. This work provides an approach for addressing the issue of poor thermal resistance of metal-coated polymeric materials due to the inherent low melting point of the organic support.