Cambrian Acyclic Domains: Countingc-singletons
ORDER-A JOURNAL ON THE THEORY OF ORDERED SETS AND ITS APPLICATIONS
Authors: Labbe, Jean-Philippe; Lange, Carsten E. M. C.
Abstract
We study the size of certain acyclic domains that arise from geometric and combinatorial constructions. These acyclic domains consist of all permutations visited by commuting equivalence classes of maximal reduced decompositions if we consider the symmetric group and, more generally, of allc-singletons of a Cambrian lattice associated to the weak order of a finite Coxeter group. For this reason, we call these setsCambrian acyclic domains. Extending a closed formula of Galambos-Reiner for a particular acyclic domain called Fishburn's alternating scheme, we provide explicit formulae for the size of any Cambrian acyclic domain and characterize the Cambrian acyclic domains of minimum or maximum size.
A Novel Computing Power Allocation Algorithm for Blockchain System in Multiple Mining Pools Under Withholding Attack
IEEE ACCESS
Authors: Chen, Yourong; Chen, Hao; Han, Meng; Liu, Banteng; Chen, Qiuxia; Ren, Tiaojuan
Abstract
To overcome the fast-changing block withholding attacks among multiple mining pools composed of miners in the blockchain system, this paper proposes a mining pool computing power allocation (MPPA) algorithm, which significantly improves the revenues of mining pools with block withholding attacks. MPPA first establishes the revenue optimization model of mining pools, which includes current adequate total computing power, the revenues of honest mining, and the revenues of block withholding attacks. Then MPPA calculates the revenue gain generated by block withholding attacks on other mining pools. To adjust the fixed computing power in each iteration, we have the mining pool computing power allocation algorithm with a fixed change of computing power (MPPA_F). To adjust the optimal recovery and attack computing power, we have the mining pool computing power allocation algorithm with an optimal change of computing power (MPPA_O). The simulation results demonstrate that MPPA_F and MPPA_O can find the optimized solutions of power computing allocation for each mining pool and outperform the state-of-arts such as WSFS, ALLC, and ALLD.