Research on Joint Resource Allocation for Multibeam Satellite Based on Metaheuristic Algorithms

With the rapid growth of satellite communication demand and the continuous development of high-throughput satellite systems, the satellite resource allocation problem—also called the dynamic resources management (DRM) problem—has become increasingly complex in recent years. The use of metaheuristic algorithms to obtain acceptable optimal solutions has become a hot topic in research and has the potential to be explored further. In particular, the treatment of invalid solutions is the key to algorithm performance. At present, the unused bandwidth allocation (UBA) method is commonly used to address the bandwidth constraint in the DRM problem. However, this method reduces the algorithm’s flexibility in the solution space, diminishes the quality of the optimized solution, and increases the computational complexity. In this paper, we propose a bandwidth constraint handling approach based on the non-dominated beam coding (NDBC) method, which can eliminate the bandwidth overlap constraint in the algorithm’s population evolution and achieve complete bandwidth flexibility in order to increase the quality of the optimal solution while decreasing the computational complexity. We develop a generic application architecture for metaheuristic algorithms using the NDBC method and successfully apply it to four typical algorithms. The results indicate that NDBC can enhance the quality of the optimized solution by 9–33% while simultaneously reducing computational complexity by 9–21%

Importance Evaluation of C⁴ISR Communication Nodes Based on Multi-attribute Decision-making

Abstract Node importance is a key measuring index for network structure characteristics. Evaluating the nodes importance can locate key nodes of the network and provide support for network node planning. The importance of the C4ISR communication node reflects the dependence degree of the functional nodes and functional links on the C4ISR transport nodes. How to transform this qualitative dependence into quantitative dependency measuring is the core problem of evaluating node importance and locating key nodes. Based on the quantitative dependence measuring, this paper proposes a C4ISR communication node importance evaluation method based on multi-attribute decision-making. Meanwhile, the applicability of the method is verified by examples.</jats:p

Research on precise organization of operational network based on “Chains in Network” model

Abstract Aiming at the network organization requirements of precise operation, this paper proposes a precise network organization method based on the “network in the chain” model: starting from the command perspective, setting the intelligence chain, C2 chain, strike chain and service chain as the entry points, the organizing and planning of operation network is classified and carried out. The model of “chain in net” is formally described, and the evaluation index system of “chain” to “net” is established. This kind of precise network organization based on command perspective is of great significance to improve the ability of joint operation based on network information system.</jats:p

Design and Analysis of a Novel Shoulder Exoskeleton Based on a Parallel Mechanism

Abstract Power-assisted upper-limb exoskeletons are primarily used to improve the handling efficiency and load capacity. However, kinematic mismatch between the kinematics and biological joints is a major problem in most existing exoskeletons, because it reduces the boosting effect and causes pain and long-term joint damage in humans. In this study, a shoulder augmentation exoskeleton was designed based on a parallel mechanism that solves the shoulder dislocation problem using the upper arm as a passive limb. Consequently, the human–machine synergy and wearability of the exoskeleton system were improved without increasing the volume and weight of the system. A parallel mechanism was used as the structural body of the shoulder joint exoskeleton, and its workspace, dexterity, and stiffness were analyzed. Additionally, an ergonomic model was developed using the principle of virtual work, and a case analysis was performed considering the lifting of heavy objects. The results show that the upper arm reduces the driving force requirement in coordinated motion, enhances the load capacity of the system, and achieves excellent assistance