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One of the major challenges towards understanding and further utilizing the properties and functional behaviors of grain boundaries (GB) is the complexity of general GBs with mixed tilt and twist character. Here, we report the correlations between mixed GBs and their tilt and twist components in terms of structure, energy and stress field by computationally examining 7440 silicon GBs. Such correlations indicate that low angle mixed GBs are formed through the reconstruction mechanisms between their superposed tilt and twist components, which are revealed as the energetically favorable dissociation, motion and reaction of dislocations and stacking faults. In addition, various complex disconnection network structures are discovered near the conventional twin and structural unit GBs, implying the role of disconnection superposition in forming high angle mixed GBs. By unveiling the energetic correlation, an extended Read-Shockley model that predicts the general trends of GB energy is proposed and confirmed in various GB structures across different lattices. Finally, this work is validated in comparison with experimental observations and first-principles calculations. 

The multiple-user terminals in a satellite transponder’s communication channel compete for limited radio resources to meet their own data rate needs. Because inter-user interference limits on the satellite transponder’s performance, the transponder’s power-control system needs to coordinate all its users to reduce interference and maximizes overall performance of this channel. This paper studies Stackelberg competition among the asymmetrical users in a transponder’s channel, where some users called leader have priority to choose their power control strategy, but other users called followers have to optimize their power control strategy with given leader’s controls. A Stackelberg Differential Game (SDG) is set up to model the Stackelberg competition in a transponder’s communication channel. Each user’s utility function is a trade-off between transmission data rate and power consumption. The dynamics of the system is the changing of channel gain. The optimality condition of Stackelberg equilibrium of leaders and followers is a set of Differential Algebraic Equations (DAE) with an imbedded control strategies from its counterpart. In order to solve for Stackelberg equilibrium, an algorithm based on optimizing leaders’ and followers’ Hamiltonians iteratively is developed. The numerical solution of the SDG model provides the transponder’s power control system with each user’s power-control strategy at the Stackelberg equilibrium. 

A satellite transponder’s communication channel is studied in this paper. The multiple terminal users in this channel compete for limited radio resources to satisfy their own data rate needs. Because inter-user interference limits the transponder’s performance, it is beneficial for the transponder’s power-control system to coordinate all users in its channel to reduce interference and to improve performance. By the special properties of channel gain in this type of channel, a non-cooperative Differential Game (DG) is set up to study the competition in a transponder’s channel. Each user’s utility is a trade-off between transmission data rate and power consumption. Nash Equilibrium (NE) is defined to be the solution of the DG model. The optimality condition of NE is derived to be a system of Differential Algebraic Equations (DAE). An algorithm based on minimizing all users’ Hamiltonian is developed to solve the DAE system. The numerical solution of the NE provides the transponder’s power control system with each user’s power-control strategy at the equilibrium. 

This paper studies a satellite transponder’s communication channel, in which there exist multiple-user terminals, who compete for limited radio resources to meet their own data rate needs. Because inter-user interference limits on the satellite transponder’s performance, the transponder’s power-control system needs to coordinate all its users to reduce interference and maximizes overall performance. A non-cooperative Differential Game (DG) is set up to model the users’ competition in a transponder’s communication channel. Each user’s utility function is a trade-off between transmission data rate and power consumption. Nash Equilibrium (NE) is defined to be the solution of the DG model. The optimality condition of NE is derived to be a set of Differential Algebraic Equations (DAE). An algorithm based on minimizing Hamiltonians is developed to solve the DAE system. The numerical solution of the DG model provides the transponder’s power control system with each user’s power-control strategy at the equilibrium. 

Abstract The currently understood principles about light–molecule interactions are limited, and thus scientific scope beyond current theories is rarely harvested. Herein we demonstrate supracence phenomena, in which the emitted photons have more energy than the absorbed photons. The extra energy comes from couplings of the absorbed and emitted photon to molecular phonons, whose potentials are constantly exchanging with molecular quantum energy and the environment. Thus, supracence is a linear optical process rather than a nonlinear optical process, such as second harmonic generation. Because supracence results in cooled molecular phonons and thus cooled molecules, behavior opposite to that of hot fluorescing emitters is expected. This report reveals certain supracence principles while contrasting fluorescence with supracence in high‐resolution imaging.