Information reconciliation protocol has a significant effect on the secret key rate and maximal transmission distance of continuous-variable quantum key distribution (CVQKD) systems. We propose an efficient rate-adaptive reconciliation protocol suitable for practical CV-QKD systems with time-varying quantum channel. This protocol changes the code rate of multi-edge type low density parity check codes, by puncturing (increasing the code rate) and shortening (decreasing the code rate) techniques, to enlarge the correctable signal-to-noise ratios regime, thus improves the overall reconciliation efficiency comparing to the original fixed rate reconciliation protocol. We verify our rate-adaptive reconciliation protocol with three typical code rate, i.e., 0.1, 0.05 and 0.02, the reconciliation efficiency keep around 93.5%, 95.4% and 96.4% for different signal-to-noise ratios, which shows the potential of implementing high-performance CV-QKD systems using single code rate matrix.

NT-proBNP is an independent factor that could predict weaning failure. Measurement of NT-proBNP prior to SBT may be helpful in promoting successful ventilator weaning along with SBT.

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The fast and diversified development of Internet services leads to numerous services with differentiated delay tolerance of optical connections set-up are converging in the optical network. Consequently, the average set-up delay of optical connection is increased, which will inevitably bring pressures to optical networks. To solve this problem, a delay aware routing spectrum assignment (RSA) algorithm based on services scheduling in priority queues with dynamic virtual topology construction (QVT-RSA) is proposed. First, the QVT-RSA algorithm reasonably identifies various different services and arranges them in order according to their priority, waiting time and delay tolerance requirements. Then, software defined networks (SDN) controller with multi-threads technology is adopted to innovatively parallel serve the ordered service requests to reduce the average set-up delay of optical connections, which also offset the induced delay caused by services scheduling. The network resource is accurately shared among multi-threads using the proposed mutual exclusive resource utilization model realized by dynamic virtual topology construction. The continuously coloring and usable virtual topology linkage reconfiguration can provide topology resources for service requests and adapt the dynamic transformation among serving, waiting and new arriving service requests. The shortest-path routing and first fit spectrum assignment (SPFF-RSA) algorithm is used as the baseline algorithm. Furthermore, by combining the SPFF-RSA algorithm and partial strategy of our strategy, the QSPFF-RSA and V-RSA algorithms are proposed as baseline algorithms as described in V-B. The simulation experiment results demonstrate that the average optical connections set-up delay of QVT-RSA algorithm is reduced compared with SPFF-RSA and QSPFF-RSA algorithms, and the blocking probability of QVT-RSA algorithm is reduced compared with SPFF-RSA, QSPFF-RSA and VRSA algorithms. The optical connections set-up success probability within delay tolerance about high, medium and low priority services of QVT-RSA algorithm is higher than that of the SPFF-RSA, QSPFF-RSA and VRSA algorithms.INDEX TERMS Low delay, QoS, reconfiguration of virtual topology, RSA, services scheduling.

Optical Burst Switching (OBS) has been proposed to be a competitive switching technology for DWDM networks. However, the abrupt burst for large traffic loads will result in unbearable performance degradation in the traditional JET network. To combat with the load sensitivity, a wavelength-routed OBS (WR-OBS) network architecture was confirmed effective. In this paper, we have proposed a distributed control WR-OBS network architecture combining JET protocol with a two-way reservation method. Based on this architecture, two new resource reservation protocols are compared by evaluating their performance. Then based on the Reduced Load Approximation, which is often used in the analysis of the circuit switch network, a novel analysis method was derived to evaluate the blocking performance of the network. And then we have developed a simulation model to evaluate the performance of the network and validate the proposed analysis method. Analytical and simulation results have indicated that the proposed architecture outperforms the traditional JET OBS network in burst blocking probability with a good trade-off between efficiency and complexity.