Owing to its efficiency in solving some types of large-scale separable optimization problems with linear constraints, the convergence rate of the alternating direction method of multipliers(ADMM for short) has recentl...
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Owing to its efficiency in solving some types of large-scale separable optimization problems with linear constraints, the convergence rate of the alternating direction method of multipliers(ADMM for short) has recently attracted significant attention. In this paper, we consider the generalized ADMM(G-ADMM), which incorporates an acceleration factor and is more efficient. Instead of using a solution measure that depends on a bounded set and cannot be easily estimated, we propose using the original ?-optimal solution measure, under which we prove that the G-ADMM converges at a rate of O(1/t). The new bound depends on the penalty parameter and the distance between the initial point and the solution set, which is more reasonable than the previous bound.
Visual relationship detection aims to predict the relationships between detected object pairs. It is well believed that the correlations between image components (i.e., objects and relationships between objects) are s...
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The structural and elastic properties of multiferroic Ca3Mn2O7 with ferroelectric orthorhombic （O-phase） and paraelectric tetragonal structures （T-phase） have been studied by first-principles calculations within t...
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The structural and elastic properties of multiferroic Ca3Mn2O7 with ferroelectric orthorhombic （O-phase） and paraelectric tetragonal structures （T-phase） have been studied by first-principles calculations within the generalized gradient approximation （GGA） and the GGA plus Hubbard U approaches （GGA ＋ U）. The calculated theoretical structures are in good agreement with the experimental values. The T-phase is found to be antiferromagnetic （AFM） and the AFM O-phase is more stable than the T-phase, which also agree with the experiments. On these bases, the single-crystal elastic constants （Cijs） and elastic properties of polycrystalline aggregates are investigated for the two phases. Our elasticity calculations indicate Ca3Mn2O7 is mechanically stable against volume expansions. The AFM O-phase is found to be a ductile material, while the AFM T-phase shows brittle nature and tends to be elastically isotropic. We also investigate the influence of strong correlation effects on the elastic properties, qualitatively consistent results are obtained in a reasonable range of values of U. Finally, the ionicity is discussed by Bader analysis. Our work provides useful guidance for the experimental elasticity measurements of Ca3Mn2O7, and makes the strain energy calculation in multiferroic Ca3Mn2O7 thin films possible.
The effects of the Dzyaloshinski-Moriya （DM） interaction on the ground-state properties of the anisotropic XY chain in a transverse field have been studied by means of correlation functions and entanglement. Differe...
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The effects of the Dzyaloshinski-Moriya （DM） interaction on the ground-state properties of the anisotropic XY chain in a transverse field have been studied by means of correlation functions and entanglement. Different from the case without the DM interaction, the excitation spectra ek of this model are not symmetrical in the momentum space and are not always positive. As a result, besides the ferromagnetic （FM） and the paramagnetic （PM） phases, a gapless chiral phase is induced. In the chiral phase, the von Neumann entropy is proportional to log2 L （L is the length of a subchain） with the coefficient A ~ 1/3, which is the same as that of the XY chain in a transverse field without the DM interaction for 7 = 0 and 0 〈 h 〈 1. And in the vicinity of the critical point between the chiral phase and the FM （or PM） phase, the behaviors of the nearest- neighbor concurrence and its derivative are like those for the anisotropy transition.
We address the fine-grained image recognition problem using user click data, wherein each image is represented as a semantical query-click feature vector. Usually, the query set obtained from search engines is large-s...
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Aiming at the problem of periodic interference in flight simulation turntables, a design method of full-form dynamic linearization model free adaptive control (FFDL-MFAC) is proposed. An equivalent dynamic linearized ...
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The presence of inverter based renewable resources has introducing new challenges on transmission systems due sudden loss of several MW after voltage and frequency excursions. These sudden disconnections have been rel...
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ISBN:
(纸本)9781728116266
The presence of inverter based renewable resources has introducing new challenges on transmission systems due sudden loss of several MW after voltage and frequency excursions. These sudden disconnections have been related with a fault ride through control in voltage and frequency excursions following PRC-024 standard. The NERC Inverter-Based Resource Performance Task Force has expressed the necessity for a full ride-through standard with clear requirements as to how the resource can behave in terms on control and protection aspects. In consequence, this article addresses the problem to define the control and protection that can be taken under frequency and voltage excursions to avoid disconnections. For this purpose, this article proposes a new magnitude and frequency computation with computations delays under 16 ms and the use of new detection techniques to add new control and protection functions to the inverter based renewable resources.
City traffic often exhibits regional characteristics, such as large trucks frequently appearing in the suburbs, and the paths to playgrounds on weekends generally being congested. Discovering and visualizing these hid...
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Update summarization can be a daunting task in automatic text summarization. It aims to distill evolved messages from a collection of new articles, under the assumption that the reader has already browsed the previous...
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Due to the turbulent external business environment, the complexity of internal relations of the organization and the emergence of subversive IT roles, the business-IT alignment(BITA)has become increasingly difficult. ...
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Due to the turbulent external business environment, the complexity of internal relations of the organization and the emergence of subversive IT roles, the business-IT alignment(BITA)has become increasingly difficult. The unsuccessful realization of BITA will lead to the waste of organizational resources, the reduction of return on investment and eventually the loss of competitive advantage. In recent years, coevolution has received widespread attention due to its ability to describe the dynamic relationship between IT and business. Multiple principles such as quickening learning action loops and adopt suitable organizing principles for achieving business and IT coevolution(BITC) are obtained. However, the continuous BITC is still hard to be achieved because of the lack of complete BITC management. This paper focuses on the management process of the BITC and how to perform it gradually. A coevolution framework combines the enterprise architecture(EA) approach with the coevolution analysis is proposed, which contains the design of EA, the sensing and governance of the misalignment and the procedure of the EA misalignment *** steps for the governance and prevention of misalignment are discussed in particular. Through comparison with the principles,characteristics and methods of coevolution in the literature, the proposed framework is evaluated. The results show that the proposed framework is effective for BITC implementation.
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