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npj Computational Materials 2020年第1期6卷 1272-1279页

作者： Kamal Choudhary Kevin F.Garrity Jie Jiang Ruth Pachter Francesca Tavazza Materials Science and Engineering Division National Institute of Standards and TechnologyGaithersburgMD 20899USA Materials Directorate Air Force Research LaboratoryWright–Patterson Air Force BaseOH 45433USA

Two-dimensional topological materials(2D TMs)have a variety of properties that make them attractive for applications including spintronics and quantum computation.However,there are only a few such experimentally known materials.To help discover new 2D TMs,we develop a Unified and computationally inexpensive approach to identify magnetic and non-magnetic 2D TMs,including gapped and semi-metallic topological classifications,in a high-throughput way using density functional theory-based spin–orbit spillage,Wannier-interpolation,and related techniques.

关键词： materials Unified topological

A novel Unified model predicting flow stress and grain size evolutions during hot working of non-uniform as-cast 42CrMo billets

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Chinese Journal of Aeronautics 2019年第2期32卷 531-545页

作者： Lianggang GUO Fengqi WANG Pengliang ZHEN Xuechao LI Mei ZHAN School of Materials Science and Engineering Northwestern Polytechnical University

The cast preformed forming process(CPFP) is increasingly considered and applied in the metal forming industries due to its short process, low cost, and environmental friendliness, especially in the aerospace field. However, how to establish a Unified model of a non-uniform as-cast billet depicting the flow stress and microstructure evolution behaviors during hot working is the key to microstructure prediction and parameter optimization of the CPFP. In this work, hot compression tests are performed using a non-uniform as-cast 42 CrMo billet at 1123–1423 K and 0.01–1sà1. The effect laws of the non-uniform state of the as-cast billet with different initial grain sizes on the flow stress and microstructure are revealed deeply. Based on experimental results, a Unified model of flow stress and grain size evolutions is developed by the internal variable modeling method. Verified results show that the model can well describe the responses of the flow stress and microstructure to deformation conditions and initial grain sizes. To further evaluate its reliability, the Unified model is applied to FE simulation of the cast preformed ring rolling process.The predictions of the rolling force and grain size indicate that it could well describe the flow stress and microstructure evolutions during the process.

关键词： Cast preformed forming process Flow stress Grain size Non-uniform as-cast 42CrMo billet Ring rolling Unified model

A Unified gas-kinetic scheme for multiscale and multicomponent flow transport

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Applied Mathematics and Mechanics(English Edition) 2019年第3期40卷 355-372页

作者： Tianbai XIAO Kun XU Qingdong CAI Department of Mechanics and Engineering Science College of EngineeringPeking University Department of Mathematics Hong Kong University of Science and Technology Department of Mechanical and Aerospace Engineering Hong Kong University of Science and Technology Shenzhen Research Institute Hong Kong University of Science and Technology

Compressible flows exhibit a diverse set of behaviors, where individual particle transports and their collective dynamics play different roles at different scales. At the same time, the atmosphere is composed of different components that require additional degrees of freedom for representation in computational fluid dynamics. It is challenging to construct an accurate and efficient numerical algorithm to faithfully represent multiscale flow physics across different regimes. In this paper, a Unified gas-kinetic scheme(UGKS) is developed to study non-equilibrium multicomponent gaseous flows. Based on the Boltzmann kinetic equation, an analytical space-time evolving solution is used to construct the discretized equations of gas dynamics directly according to cell size and scales of time steps, i.e., the so-called direct modeling method. With the variation in the ratio of the numerical time step to the local particle collision time(or the cell size to the local particle mean free path), the UGKS automatically recovers all scale-dependent flows over the given domain and provides a continuous spectrum of the gas dynamics. The performance of the proposed Unified scheme is fully validated through numerical experiments.The UGKS can be a valuable tool to study multiscale and multicomponent flow physics.

关键词： Unified gas-kinetic scheme(UGKS) multiscale modeling multicomponent flow

Constructing a National Unified Market to Support a New Development Dynamic

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Qiu Shi 2022年第4期14卷 43-51页

作者：无 National Development and Reform Commission

Anational Unified market is a prerequisite for the creation of a new development dynamic.The recently released Guidelines of the Central Committee of the Communist Party of China and the State Council on Accelerating the Construction of a National Unified Market set out the overall arrangements for this endeavor,which is a strategic decision of the Central Committee of the Communist Party of China(CPC)with Xi Jinping at its core made on the basis of a broad view ofcurrent circumstances.

关键词： Market arrangement Unified

A Unified model for diagnosing energy usage abnormalities in regional integrated energy service systems

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Global Energy Interconnection 2019年第4期2卷 361-367页

作者： Di Wu Hongwei Ma Jianrong Mao Kaiqi Ma Hao Zheng Zhiqian Bo Xuji Group Corporation Haidian DistrictBeijing100085P.R.China Aalborg University Aalborg DK-9100Denmark CSEE UK Branch Birmingham B152TTUK

An integrated energy service company in an industrial park or commercial building is responsible for managing all energy sources in their local region, including electricity, water, gas, heating, and cooling. To reduce energy wastage and increase energy utilization, it is necessary to perform efficiency analyses and diagnoses on integrated energy systems(IESs). However, the integrated energy data necessary for energy efficiency analyses and diagnoses come from a wide variety of instruments, each of which uses different transmission protocols and data formats. This makes it challenging to handle energy-flow data in a Unified manner. Thus, we have constructed a Unified model for diagnosing energy usage abnormalities in IESs. Using this model, the data are divided into working days and non-working days, and benchmark values are calculated after the data have been weighted to enable Unified analysis of several types of energy data. The energy-flow data may then be observed, managed, and compared in all aspects to monitor sudden changes in energy usage and energy wastage. The abnormal data identified and selected by the Unified model are then subjected to big-data analysis using technical management tools, enabling the detection of user problems such as abnormalities pertaining to acquisition device, metering, and energy usage. This model facilitates accurate metering of energy data and improves energy efficiency. The study has significant implications in terms of fulfilling the energy saving.

关键词： Integrated energy services Energy efficiency analysis Energy usage diagnosis Energy usage abnormalities Unified model

Building a Unified Domestic Market is of Strategic Importance

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China Forex 2022年第2期 14-16页

作者： LIAN Ping LUO Huanjie Zhixin Investment and President of Zhixin Investment Research Institute Zhixin Investment Research Institute

We need to build a Unified domestic market featuring Unified regimes,factors,resources,and supervision,along with connected trade platforms and channels for logistics and information exchanges.In this way,we can break“market segmentation”brought by local protectionism and regional barriers.This is another“deep reform”of the economy.

关键词： Market Unified market

Unified analytical solution for deep circular tunnel with consideration of seepage pressure,grouting and lining

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Journal of Central South University 2017年第6期24卷 1483-1493页

作者：李学峰杜守继陈兵 Department of Civil Engineering Shanghai Jiao Tong UniversityShanghai 200240China

A new Unified analytical solution is presented for predicting the range of plastic zone and stress distributions around a deep circular tunnel in a homogeneous isotropic continuous medium. The rock mass, grouting zone and lining are assumed as elastic-perfectly plastic and governed by the Unified strength theory(UST). This new solution has made it possible to consider the interaction between seepage pressure, lining, grouting and rock mass, and the intermediate principal stress effect together. Moreover, parametric analysis is carried out to identify the influence of the related parameters on the plastic zone radius. Under the given conditions, the results show that the plastic zone radius decreases with an increasing cohesion, internal friction angle and hydraulic conductivity of lining and Unified failure criterion parameter, respectively; whereas the plastic zone radius increases with the growth of elasticity modulus of lining. Comparison of results from the new solution and the other published one shows well agreement and provides confidence in the new solution proposed.

关键词： Unified strength theory (UST) intermediate principal stress seepage pressure grouting lining analytical solution

Monogamy and polygamy relations of multiqubit entanglement based on Unified entropy

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Chinese Physics B 2020年第2期29卷 129-136页

作者：靳志祥乔从丰 School of Physics University of Chinese Academy of SciencesBeijing 100049China CAS Center for Excellence in Particle Physics Beijing 100049China

Monogamy relation is one of the essential properties of quantum entanglement,which characterizes the distribution of entanglement in a multipartite system.By virtual of the Unified-(q,s)entropy,we obtain some novel monogamy and polygamy inequalities in general class of entanglement measures.For the multiqubit system,a class of tighter monogamy relations are established in term of the α-th power of Unified-(q,s)entanglement for α≥1.We also obtain a class of tighter polygamy relations in the β-th(0≤β≤1)power of Unified-(q,s)entanglement of assistance.Applying these results to specific quantum correlations,e.g.,entanglement of formation,Renyi-q entanglement of assistance,and Tsallis-q entanglement of assistance,we obtain the corresponding monogamy and polygamy relations.Typical examples are presented for illustration.Furthermore,the complementary monogamy and polygamy relations are investigated for the α-th(0≤α≤ 1)and β-th(β≥1)powers of Unified entropy,respectively,and the corresponding monogamy and polygamy inequalities are obtained.

关键词： quantum monogamy quantum polygamy Unified entropy

Subsynchronous resonance and its mitigation for power system with Unified power flow controller

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Journal of Modern Power Systems and Clean Energy 2018年第1期6卷 181-189页

作者： Xinyao ZHU Meng JIN Xiangping KONG Jingbo ZHAO Jiankun LIU Qian ZHOU State Grid Jiangsu Electric Power Research Institute State Grid Jiangsu Electric Power Maintenance Branch Company

Control strategy of Unified power flow controller(UPFC)utilizing dq decoupling control is deduced in this paper,which can closely follow the control orders of the active and reactive power.The subsynchronous resonance(SSR)characteristics of a series compensated system equipped with UPFC are studied,and the results reveal that SSR characteristics of the system may vary significantly with UPFC in service or not.Consequently,supplementary subsynchronous damping controller(SSDC)for UPFC is proposed and investigated,and the effectiveness of the proposed SSDC is verified by damping torque analysis and time domain simulations.

关键词： Unified power flow controller(UPFC) Series capacitor compensation Subsynchronous resonance(SSR) Supplementary subsynchronous damping controller(SSDC) Damping torque analysis

Development of a Unified viscoplasticity constitutive model based on classical plasticity theory

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Science China(Technological Sciences) 2009年第5期52卷 1248-1253页

作者： GUAN Ping LIU ChangChun Lü HeXiang College of Architectural Engineering Dalian UniversityDalian 116622China State Key Laboratory of Structural Analysis for Industrial Equipment Dalian University of TechnologyDalian 116024China

The traditional Unified viscoplasticity constitutive model can be only applied to metal materials.The study of the Unified constitutive theory for metal materials has discovered the correlation between the classical plasticity theory and the Unified viscoplasticity constitutive model,thus leading to the con-cepts of the classic plastic potential and yield surface in the Unified constitutive model.Moreover,this research has given the continuous expression of the classical plastic multiplier and presented the corresponding constructive method,which extends its physical significance and lays down a good foundation for the application of the Unified constitutive theory to the material analysis in more fields.This paper also introduces the Unified constitutive model for metal materials and geo-materials.The numerical simulation indicates that the construction should be both reasonable and practical.

关键词： viscoplasticity classical plasticity Unified constitutive model plastic potential yield surface