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Entanglement and Energy for Vibrationally Localized States in Molecule CS2

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Chinese Journal of Chemical Physics 2015年第3期28卷 295-298,I0001页

作者： Zi-xin Yang xing shen Xi-wen Hou Department of Physics Huazhong Normal University Wuhan 430079 China

The dynamics of quantum entanglement described by the yon Neumann entropy is studied for the localized states of Fermi-resonance coupling vibrations in molecule CS2, where the interacting energy between the stretching and the bending modes is considered to establish a connection between entanglement and energy. It is shown that entanglement reveals dominant anti-correlation with the interacting energy for the stretch-localized state, while that exhibits dominantly positive correlation for the bend-localized state. The entanglement and the energy for the dislocalized states are discussed as well. Those are useful for molecular quantum computing and quantum information in high dimensional states.

关键词： Entanglement Quantum entropy Vibrational analysis

Z-parameter Method for Damage Evaluation in HK40 Steel

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Journal of Materials Science & Technology 2007年第3期23卷 329-332页

作者： Li xing Jie ZHAO Fuzhong shen Wei FENG State Key Laboratory of Materials Modification School of Materials Science and Engineering Dalian University of Technology Dalian 116024 China Nanjing University of Technology Nanjing 210009 China

A Z-parameter method is used to evaluate the damage process of HK40 austenitic steel. By using Z-parameter based on the Larson-Miller method, the nonlinear master curve of the log stress vs Larson-Miller parameter P can be expressed as： P=27.74-3.41gσ-0.032σ, and a family of curves parallel to the master curve can be written as： P=（27.74-Z）-3.41gσ-0.032σ, where Z represents the magnitude of the deviation from the master curve. According to the creep rupture data both from different segments of a serviced tube and from the same segment locations with different service time, the value of parameter Z has close relationship with the deterioration of creep rupture properties. The damage state of the samples is evaluated by monitoring the changes in natural frequency f and Young＇s modulus E, and the relationships between Z and the damage parameters are discussed.

关键词： Damage evaluation Creep rupture Austenitic steel Z-parameter

Implementation of encoder and decoder for LDPC codes based on FPGA

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Journal of Systems Engineering and Electronics 2019年第4期30卷 642-650页

作者： CHENG Kun shen qi LIAO shengkai PENG Chengzhi Department of Modern Physics University of Science and Technology of ChinaHefei 230026China Shanghai Branch National Laboratory for Physical Sciences at Microscale and Department of Modern PhysicsUniversity of Science and Technology of ChinaHefei 230026China Chinese Academy of Sciences Center for Excellence and Synergetic Innovation Center in Quantum Information and Quantum Physics University of Science and Technology of ChinaShanghai 201315China

This paper proposes a parallel cyclic shift structure of address decoder to realize a high-throughput encoding and decoding method for irregular-quasi-cyclic low-density parity-check(IR-QC-LDPC)codes,with a dual-diagonal parity structure.A normalized min-sum algorithm(NMSA)is employed for *** whole verification of the encoding and decoding algorithm is simulated with Matlab,and the code rates of 5/6 and 2/3 are selected respectively for the initial bit error ratio as 6%and 1.04%.Based on the results of simulation,multi-code rates are compatible with different basis *** the simulated algorithms of encoder and decoder are migrated and implemented on the field programmable gate array(FPGA).The 183.36 Mbps throughput of encoder and the average 27.85 Mbps decoding throughput with the initial bit error ratio 6%are realized based on FPGA.

关键词： low-density parity-check(LDPC) field programmable gate array(FPGA) normalized min-sum algorithm(NMSA).

Influences of petroleum on accumulation of copper and cadmium in the polychaete Nereis diversicolor

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Journal of Environmental Sciences 2006年第1期18卷 109-114页

作者： SUN Fu-hong ZHOU qi-xing ZHANG qian-ru Key Laboratory of Terrestrial Ecological Process Institute of Applied Ecology Chinese Academy of Sciences Shenyang 110016 China Graduate School of the Chinese Academy of Sciences Beijing 100039 China College of Environmental Sciences and Engineering Nankai University Tianjin 300071 China

Using the exposure simulation experiment, the action of petroleum affecting the accumulation of the trace metals including copper （Cu） and cadmium （Cd） in littoral polychaete Nereis diversicolor collected from the Shuangtaizi Estuary in Liaoning Province, China was examined. The results showed that there was a markedly non-linear relationship between the accumulation of Cu in worms and the experimental concentration of Cu in exposure solutions when the concentration of petroleum remained at 0, 100, and 220 μl/L, respectively. However, significantly non-linear relationship for worms exposed to Cd was observed only when the concentration of added petroleum was 0 and 220 μl/L. The accumulation of Cu in worms did not differ significantly among the three different levels of petroleum concentrations combined with various concentrations of Cu. So was the accumulation of Cd in worms （p〉0.05）. However, the addition of petroleum in exposure solutions brought about an increase in the accumulation of Cu in Nereis diversicolor, in comparison with single Cu pollution. On the other hand, when the concentration of added petroleum remained at 100 μl/L, the accumulation of Cd in worms was lower than that in worms exposed to various concentrations of only cadmium. However, the worms exposed to Cd and petroleum 220 μl/L did not show obvious and identical increase in the accumulation of Cd, compared with single Cd exposure. The accumulation of both Cu and Cd in worms did not increase significantly with the increases in concentrations of Cu or Cd in exposure solutions combined with petroleum （0, 100, and 220μl/L） under the experimental conditions. Although Nereis diversicolor is exposed to very high Cu and Cd in exposure solutions, accumulation and detoxification mechanisms are sufficient to cope with the extra metal influx in order to survive.

关键词： Nereis diversicolor copper cadmium petroleum combined pollution

Improved Double Deep Q Network-Based Task Scheduling Algorithm in Edge Computing for Makespan Optimization

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Tsinghua Science and Technology 2024年第3期29卷 806-817页

作者： Lei Zeng qi Liu Shigen shen Xiaodong Liu School of Computer Science Nanjing University of Information Science and TechnologyNanjing 210044China School of Software Nanjing University of Information Science and TechnologyNanjing 210044China School of Information Engineering Huzhou UniversityHuzhou 313000China School of Computing Edinburgh Napier UniversityEdinburghEH105DTUK

Edge computing nodes undertake an increasing number of tasks with the rise of business ***,how to efficiently allocate large-scale and dynamic workloads to edge computing resources has become a critical *** study proposes an edge task scheduling approach based on an improved Double Deep Q Network(DQN),which is adopted to separate the calculations of target Q values and the selection of the action in two networks.A new reward function is designed,and a control unit is added to the experience replay unit of the *** management of experience data are also modified to fully utilize its value and improve learning *** learning agents usually learn from an ignorant state,which is *** such,this study proposes a novel particle swarm optimization algorithm with an improved fitness function,which can generate optimal solutions for task *** optimized solutions are provided for the agent to pre-train network parameters to obtain a better cognition *** proposed algorithm is compared with six other methods in simulation *** show that the proposed algorithm outperforms other benchmark methods regarding makespan.

关键词： edge computing task scheduling reinforcement learning makespan Double Deep Q Network(DQN)

Nonadiabatic dynamics and geometric phase of an ultrafast rotating electron spin

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Science Bulletin 2019年第6期64卷 380-384页

作者： xing-Yan Chen Tongcang Li Zhang-qi Yin Center for Quantum Information Institute for Interdisciplinary Information Sciences Tsinghua University Max-Planck-Institut für Quantenoptik Fakult?t für Physik Ludwig-Maximilians-Universit?t München Department of Physics and Astronomy Purdue University School of Electrical and Computer Engineering Purdue University Purdue Quantum Center Purdue University Birck Nanotechnology Center Purdue University

The spin in a rotating frame has attracted a lot of attentions recently,as it deeply relates to both fundamental physics such as pseudo-magnetic field and geometric phase,and applications such as gyroscopic ***,previous studies only focused on adiabatic limit,where the rotating frequency is much smaller than the spin *** we propose to use a levitated nano-diamond with a built-in nitrogen-vacancy(NV)center to study the dynamics and the geometric phase of a rotating electron spin without adiabatic *** find that the transition between the spin levels appears when the rotating frequency is comparable to the spin frequency at zero magnetic *** we use Floquet theory to numerically solve the spin energy spectrum,study the spin dynamics and calculate the geometric phase under a finite magnetic field,where the rotating frequency to induce resonant transition could be greatly reduced.

关键词： Nitrogen-vacancy center Nonadiabatic geometric phase Ultrafast rotor Rabi oscillation Optomechanics

Influence of coronary bifurcation angle on atherosclerosis

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Acta Mechanica Sinica 2019年第6期35卷 1269-1278页

作者： Zhaomiao Liu shengwei Zhao Yunjie Li Feng shen Yipeng qi qi Wang College of Mechanical Engineering and Applied Electronics Technology Beijing University of TechnologyBeijing 100124China Department of Cardiology PLA General HospitalBeijing 100853China

Hemodynamics plays a crucial role in the development and progression of coronary atherosclerosis,which is prone to occur in branch bifurcation.A n individual aortic-coronary artery model and three changed bifurcation angle models are constructed by Mimics and Freeform based on computed tomography *** influence of different coronary bifurcation angles between left main(LM),left anterior descending(LAD),and left circumflex(LCX)on the blood flow field and related hemodynamic parameters are *** is shown that a wider bifurcation angle between LAD and LCX can cause a wider low-wall shear stress area,leading to ***,a decreased angle between LM and LAD is predisposed to prevent *** results help to better understand the hemodynamic causes of atherosclerosis with various bifurcation angles in coronary arteries and to provide guidance for clinical assessment and prevention.

关键词： Atherosclerosis Coronary artery Bifurcation angle Hemodynamics Wall shear stress

Optimizing Non-Decomposable Evaluation Metrics for NeuralMachine Translation

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Journal of Computer Science & Technology 2017年第4期32卷 796-804页

作者： Shi-qi shen Yang Liu Mao-Song Sun Department of Computer Science and Technology Tsinghua University Beijing 100084 China State Key Laboratory of Intelligent Technology and Systems Tsinghua University Beijing 100084 China Tsinghua National Laboratory for Information Science and Technology Tsinghua University Beijing 100084 China Jiangsu Collaborative Innovation Center for Language Ability Jiangsu Normal University Xuzhou 221009 China

While optimizing model parameters with respect to evaluation metrics has recently proven to benefit end to-end neural machine translation (NMT), the evaluation metrics used in the training are restricted to be defined at the sentence level to facilitate online learning algorithms. This is undesirable because the final evaluation metrics used in the testing phase are usually non-decomposable (i.e., they are defined at the corpus level and cannot be expressed as the sum of sentence-level metrics). To minimize the discrepancy between the training and the testing, we propose to extend the minimum risk training (MRT) algorithm to take non-decomposable corpus-level evaluation metrics into consideration while still keeping the advantages of online training. This can be done by calculating corpus-level evaluation metrics on a subset of training data at each step in online training. Experiments on Chinese-English and English-French translation show that our approach improves the correlation between training and testing and significantly outperforms the MRT algorithm using decomposable evaluation metrics.

关键词： neural machine translation training criterion non-decomposable evaluation metric

The magnetic properties and magnetocaloric effects in binary R-T(R = Pr,Gd,Tb,Dy,Ho,Er,Tm;T = Ga,Ni,Co,Cu)intermetallic compounds

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Chinese Physics B 2017年第2期26卷 1-41页

作者： Xin-qi Zheng Bao-Gen shen School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China Institute of Physics Chinese Academy of Sciences and University of Chinese Academy of Sciences Beijing 100190 China

In this paper, we review the magnetic properties and magnetocaloric effects（MCE） of binary R–T（R = Pr, Gd, Tb,Dy, Ho, Er, Tm; T = Ga, Ni, Co, Cu） intermetallic compounds（including RGa series, RNi series, R_（12）Co_7 series, R_3 Co series and RCu_2series）, which have been investigated in detail in the past several years. The R–T compounds are studied by means of magnetic measurements, heat capacity measurements, magnetoresistance measurements and neutron powder diffraction measurements. The R–T compounds show complex magnetic transitions and interesting magnetic *** types of magnetic transitions are investigated and confirmed in detail by multiple approaches. Especially, most of the R–T compounds undergo more than one magnetic transition, which has significant impact on the magnetocaloric effect of R–T compounds. The MCE of R–T compounds are calculated by different ways and the special shapes of MCE peaks for different compounds are investigated and discussed in detail. To improve the MCE performance of R–T compounds,atoms with large spin（S） and atoms with large total angular momentum（J） are introduced to substitute the related rare earth atoms. With the atom substitution, the maximum of magnetic entropy change（？SM）, refrigerant temperature width（Twidth）or refrigerant capacity（RC） is enlarged for some R–T compounds. In the low temperature range, binary R–T（R = Pr, Gd,Tb, Dy, Ho, Er, Tm; T = Ga, Ni, Co, Cu） intermetallic compounds（including RGa series, RNi series,R_（12）Co_7 series, R_3 Co series and RCu_2series） show excellent performance of MCE, indicating the potential application for gas liquefaction in the future.

关键词： magnetocaloric effect magnetic entropy change magnetic property neutron diffraction magnetic structure