An Improved Multi-Stage Preconditioner on GPUs for Compositional Reservoir Simulation

The compositional model is often used to describe multicomponent multiphase porous media flows in the petroleum industry. The fully implicit method with strong stability and weak constraints on time-step sizes is commonly used in the mainstream commercial reservoir simulators. In this paper, we develop an efficient multi-stage preconditioner for the fully implicit compositional flow simulation. The method employs an adaptive setup phase to improve the parallel efficiency on GPUs. Furthermore, a multi-color Gauss-Seidel algorithm based on the adjacency matrix is applied in the algebraic multigrid methods for the pressure part. Numerical results demonstrate that the proposed algorithm achieves good parallel speedup while yields the same convergence behavior as the corresponding sequential version.Comment: 24 pages, 4 figures, and 8 tables. arXiv admin note: text overlap with arXiv:2201.0197

Retraction and Generalized Extension of Computing with Words

Fuzzy automata, whose input alphabet is a set of numbers or symbols, are a formal model of computing with values. Motivated by Zadeh's paradigm of computing with words rather than numbers, Ying proposed a kind of fuzzy automata, whose input alphabet consists of all fuzzy subsets of a set of symbols, as a formal model of computing with all words. In this paper, we introduce a somewhat general formal model of computing with (some special) words. The new features of the model are that the input alphabet only comprises some (not necessarily all) fuzzy subsets of a set of symbols and the fuzzy transition function can be specified arbitrarily. By employing the methodology of fuzzy control, we establish a retraction principle from computing with words to computing with values for handling crisp inputs and a generalized extension principle from computing with words to computing with all words for handling fuzzy inputs. These principles show that computing with values and computing with all words can be respectively implemented by computing with words. Some algebraic properties of retractions and generalized extensions are addressed as well.Comment: 13 double column pages; 3 figures; to be published in the IEEE Transactions on Fuzzy System

Abnormal Gastroscopy Findings Were Related to Lower Meridian Energy

According to the theories of Traditional Chinese Medicine (TCM), energy runs through 12 meridians longitudinally up and down the body. The study objectives were to compare the meridian energy between subjects with and without abnormal gastroscopy findings. We applied a cross-sectional and correlational research design. The study included 1,223 participants who had their health examinations at a university hospital in Taipei from 1st August 2005 through 31st August 2007. Meridian energy was examined using a meridian energy analysis device. The gastroscopy was operated by certified gastroenterologists. Participants with abnormal stomach and esophageal findings using gastroscopy had significantly lower mean meridian energy. There were no significant differences in meridian energy between participants with and without abnormal duodenum findings. When all of the meridians were examined individually, participants with abnormal findings in esophagus and stomach had significantly lower meridian energy in each of the meridians. The results of this study demonstrated that structural abnormality in the gastric area was related to lower meridian energy. Whether enhancing meridian energy could improve gastric and esophageal health merits further studies

Diaqua­bis(benzyl­oxyacetato)copper(II)

In the title mononuclear complex, [Cu(C9H9O3)2(H2O)2], the CuII ion, located on an inversion center, is hexa­coordinated by four O atoms from two benzyl­oxyacetate ligands [Cu—O = 1.9420 (14) and 2.2922 (14) Å] and two water mol­ecules [Cu—O = 2.0157 (15) Å] in a distorted octa­hedral geometry. In the crystal structure, inter­molecular O—H⋯O hydrogen bonds link the mol­ecules into layers parallel to the bc plane

Digital Quantum Simulation of Yang-Mills Theory and Hadronization

A quantum algorithm with polynomial complexity to non-perturbatively calculate the Dyson series of SU(N) Yang-Mills theory is formulated in terms of quantum circuits. Applying it to the quantum simulation of quantum chromodynamics (QCD), the quark and gluon's wave functions evolved from the initial states by the interactions can be observed and the information from wave functions can be extracted at any discrete time. This may help us understand the natures of the hadronization which has been an outstanding question of significant implication on high energy phenomenological studies.Comment: 8 pages, 1 figur