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Objective To develop an in vitro model of the renal pelvis to compare intrarenal pressure(IRP) and irrigation flow at various suspended water heights during flexible ureteroscopy (fURS).Methods A 100 mL saline bag was used to simulate the renal pelvis. The fURS sheath was connected to the bag and the ureteric access sheath (UAS) was positioned at the junction of the ureteropelvic region. Central venous pressure tubing was connected to monitor the pressure in the renal pelvis under different conditions. Two different sheath sizes (12Fr and 14Fr) were tested with fURS sizes of 7.5, 8.5, and 9.5Fr, respectively. The perfusion method was gravity based, and the hanging water heights were set at 60, 90, 120, 150, and 180 cm. A separate manual pumping group was also measured.Results In the group using a 12Fr sheath, the use of a 9.5Fr flexible ureteroscope without accessories resulted in a minimum gravity perfusion pressure of 8.4 cmH2O and a maximum pressure of 17.5cmH2O. However, manually administering perfusion in the pelvis produced pressures exceeding 60cmH2O. When the fURS was employed with a 200um laser fiber within the same sheath size, the minimum pressure of gravity perfusion decreased to 6.4cmH2O, and the maximum pressure was 10.5cmH2O. The IRP reached 48cmH2O while hand pumping. In the 14Fr sheath group, while using a 9.5Fr fURS, minimum and maximum gravity perfusion pressures were 2.5cmH2O and 6.0cmH2O, respectively. In contrast, manual perfusion resulted in a pressure of 17cmH2O. For the 12Fr sheath group using a 7.5Fr fURS, the minimum pressure of gravity perfusion was 5.4cmH2O, the maximum was 8.2H2O, and renal pelvic pressure during manual perfusion was 25.5cmH2O.Conclusion It is safe and efficient to hang the water at different heights during the operation of the disposable ureteroscopy to maintain low and safe IRP when using a UAS.

Background Traditional prone position (TP) and prone split-leg position are two commonly used operative positions for percutaneous nephrolithotomy (PCNL). However, when confronting with the situation of endoscopic combined intrarenal surgery, the former could not avoid the need of position change while the latter requires flexible retrograde ureteroscopy (fURS) with higher cost. The current study optimized a novel technique for performing percutaneous nephrolithotomy (PCNL) in the knee-flexion prone split-leg position (KF-PSL)and evaluated the safety, advantages, and feasibility compare to the traditional prone position (TP). Methods An evolution of technique based on common prone split-leg position (PSL) was presented, and a retrospective analysis was conducted on the data of 105 patients who underwent PCNL in KF-PSL or TP position between January 2021 and June 2021. The demographic and preoperative clinical data of the KF-PSL and TP groups were reviewed, and the preoperative, perioperative, and postoperative parameters were compared. Results The perioperative manifestations of 51 patients who underwent PCNL in the KF-PSL position and 54 patients in the TP position were analyzed. The preoperative parameters of the two groups did not differ significantly. The mean stone size was 43.38±29.64 mm in maximum diameter. S.T.O.N.E. scores greater than 11 accounted for 11.4%. The mean operative time (85.4±47.7 mins in KF-PSL vs 109.6±48.9 mins in TP) was a significant index (PConclusion The KF-PSL is a promising novel position that allows a shorter operative time and more simplified surgical procedure for PCNL than TP without compromising the outcome. It is more convenient for combined therapy, which allows access to the entire urinary tract without the need for changing position. KF-PSL is a safe, efficient, and versatile position that enables the complete resolution of large stones in a single procedure. Trial registration ChiCTR2200055385, 8th, January, 2021.

The joint scheduling of multi energy micro energy network group can effectively absorb the residual heat of electricity in each sub micro network through the characteristics of energy substitutability and multi-agent interaction. However, the complex relationship of multi energy interaction brings difficulties to joint scheduling. In order to minimize the operating cost of the system, this paper establishes a day ahead optimal scheduling model of multi energy micro grid group of cooling, heating and power considering the consumption of clean energy. Through thejoint scheduling of micro grid group, it can promote the consumption of residual heat in the sub micro grid. Finally, in an example, by optimizing the operation of a multi-functional microgrid group, the mechanism of joint scheduling of multifunctional microgrid group is analyzed, and the effectiveness of the optimization operation model proposed in this paper is verified.

Clean energy power generation has good economic and social benefits for promoting regional development. However, clean energy power generation is in the growth stage, and the difference of investment income is obvious. Therefore, it is of great significance to study the economy of clean energy power generation technology. In view of this, considering the influencing factors on economy of clean energy power generation technology, this paper proposes a technical economy evaluation and cost trend analysis model for clean energy power generation, which includes three modules: input, output and analysis calculation. Finally, taking Africa as an example, under the three scenarios of high utilization hours, medium utilization hours and low utilization hours, the paper analyzes the economy of photovoltaic power generation in Africa, and concludes that the cost of photovoltaic power generation in the northern and southern of Africa has a certain degree of network transmission economy.

As China’s environment and climate problems become more and more serious, the integrated energy system is booming. However, the coupling between various systems is not strong, and it is urgent to increase the coupling between multiple systems. Taking the total cost of the integrated energy system as the objective function, the independent operation and coupling transformation of the power system, natural gas system and thermal system within the system are considered. In this paper, a system planning model is built to meet the three types of loads in the system: electric load, thermal load and gas load, so as to increase the coupling of the system, ensure the reliable operation of the integrated energy system and improve the energy utilization efficiency.

In this paper, a new robot path planning algorithm based on Quantum-inspired Evolutionary Algorithm (QEA) is proposed. QEA is an advanced evolutionary computing scheme with the quantum computing features such as qubits and superposition. It is suitable for solving large scale optimization problems. The proposed QEA algorithm works in the discretized environment, and approximates the optimal robot planing path in a highly computationally efficient fashion. The simulation results indicate that the proposed QEA algorithm is suitable for both complex static and dynamic environment and considerably outperforms the conventional genetic algorithm (GA) for solving the robot path planning problem. Our algorithm runs in only about 2[Formula: see text]s, which demonstrates that it can well tackle the optimization problem in robot path planning.

In this paper, we studied a hybrid wireless network including UWB devices and WiFi devices together and analyze the characteristics of selfish behavior and the methods how to expose it. In order to improve the self-giving cooperation between the nodes in hybrid wireless networks and increase the fairness index of the whole networks, a security mechanism was proposed in this paper. The punishment mechanism was used both in a common control channel and a data channel. The results of stimulations show that the proposed protocol improves the self-giving cooperation between nodes in the networks and make the interference of the network minimum. Index Terms - security protocol, UWB, WiFi, interference

A new method is presented for scale invariant target recognition under non-uniform illumination and noisy conditions. Both overlapping additive noise and nonoverlapping background noise are considered. The method includes two steps. First, the input scene is preprocessed with estimated illumination function. Then an optimum correlation filter is designed based on modified Wiener filter(WF) model, which the reference term of WF’s transfer function is synthesized using the mean of training images . Simulation results verify the effectiveness of the proposed idea in terms of tolerance to scale distortion in presence of non-uniform illumination and noise.

As one type of the attacks happening in MAC layer of distributed cognitive radio networks, a selfish behavior can degrade network performance significantly. In this paper, we analyze the characteristics of selfish behavior and the methods how to expose it. In order to improve the self-giving cooperation between the nodes in cognitive radio networks and increase the fairness index of the whole networks, a rigorous punishment mechanism based on a puzzle model was proposed in this paper. The punishment mechanism was used both in a common control channel and a data channel. The results of stimulations show that the proposed punishment mechanism increases the fairness index of the cognitive radio networks and improves the self-giving cooperation between nodes in the networks.

A novel algorithm is presented for detecting a target placed in background and degraded by non-uniform illumination and additive noise. The algorithm includes two steps. First, the input scene is preprocessed with estimated illumination function. Then the processed scene is correlated with a designed optimum filter based on Wiener filtering. Simulation results show effectiveness of the proposed method in terms of the robustness to non-uniform illumination and noisy conditions.

Selfish behavior is one type of the attacks happening in MAC layer of distributed cognitive radio networks. In this paper, we analyze the characteristics of selfish behavior and the methods to expose it. In order to improve the self-giving cooperation between the nodes in Cognitive Radio Networks (CRNs) and increase the fairness index of the whole networks, this paper proposed a rigorous punishment mechanism based on a puzzle model. The results of stimulations show that the proposed punishment mechanism increases the fairness index of the cognitive radio networks and improves the self-giving cooperation between nodes in CRNs.

This paper investigates the QoS routing in TDMA/CDMA ad hoc networks. Since the network topology may constantly change and the available bandwidth is very limited in ad hoc networks, it's quite often to see a call is blocked when a path with required bandwidth cannot be found in the system. Therefore, we try to find multiple paths whose aggregated bandwidth can meet the bandwidth requirement and whose delays are within the required delay bound and then use the multiple paths in parallel for the QoS transmission of the call. This QoS routing we proposed can significantly reduce the system blocking probability and thus make a better use of network resources. We discuss the process of searching multiple parallel paths and proposed three heuristics (according to three parameters: property of maximum bandwidth, property of shortest path, property of maximum ratio of bandwidth to hops) to choose a group of paths whose total bandwidth satisfies the requirement. Some simulations have been conducted and the simulation results have demonstrated the deference of blocking rates gained by using the proposed three heuristics and also shown the proposed algorithms out-perform one existent on-demand algorithm.

This paper proposes a QoS routing with delay constrained and bandwidth guaranteed in TDMA/CDMA ad hoc networks. Because the wireless bandwidth is shared among adjacent nodes and the network topology changes as the nodes move, quality of service is more difficult to guarantee in ad hoc networks than in most other type of networks. QoS routing requires finding not only a route from a source to a destination, but also a route that satisfies the end-to-end QoS requirement, often given in terms of bandwidth or delay. We improve a distributed algorithm to realize the control of delays and give the method to calculate the bandwidth of a path that can be used to judge whether the bandwidth of the path satisfies the requirement. In TDMA/CDMA ad hoc networks, this is a new scheme to satisfy not only delay constrained but also bandwidth guaranteed. Some simulations have been conducted and the simulation results have demonstrated the deference of call success rate between our algorithm and other existing global algorithm or other localized algorithms that only consider delay constrained or bandwidth guaranteed.