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Journal of Quantum Information Science 2024年第2期14卷 52-67页

作者： Nasser Metwally Fawzeya Ebrahim Department of Mathematics College of Science University of Bahrain Zallaq Bahrain Department of Mathematics Aswan University Aswan Egypt

The behavior of the quantum correlations, information scrambling and the non-Markovianity of three entangling qubits systems via Rashba is discussed. The results showed that, the three physical quantities oscillate between their upper and lower bounds, where the number of oscillations increases as the Rashba interaction strength increases. The exchanging rate of these three quantities depends on the Rashba strength, and whether the entangled state is generated via direct/indirect interaction. Moreover, the coherence parameter can be used as a control parameter to maximize or minimize the three physical quantities.

关键词： Markovianity correlations Rashba Interaction Scrambling Information

Correlation Study on Grain Size Characteristics and Geotechnical Properties of Surface Sediments in Qingdao Offshore Area

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Journal of Ocean University of China 2024年第3期23卷 721-730页

作者： LI Anlong WANG Panpan GUO Xijun JI Xiangkun SHEN Kunming LIN Lin YAN Zhichao YUAN Lin Key Laboratory of Submarine Geosciences and Prospecting Techniques Ministry of Education and College of Marine GeosciencesOcean University of ChinaQingdao 266100China College of Marine Geoscience Ocean University of ChinaQingdao 266100China China Construction Second Engineering Bureau Co. LTDYueyang 414000China Tianjin Research Institute for Water Transport Engineering M.O.T.Tianjin 3000456China Lianyungang Xuwei Port Holding Group Co. Ltd.Lianyungang 222042China

The comprehension of sediment grain size parameters and the corresponding sedimentary environment holds paramount importance in elucidating the engineering geological attributes of the subaqueous seabed.This study delineated the sedimentary environment zoning in the northern sea area of Qingdao through cluster analysis of grain size parameters derived from 123 surface sediment samples.The study analyzed the correlation between sediment geotechnical indices and grain size parameters across diverse sedimentary environments.A correlation equation was established for samples exhibiting a strong correlation.The study found four distinct sedimentary environments in the study area:coastal,transitional,shallow sea,and residual.Within the same sedimentary environment,the average grain size and sorting coefficient exhibit significant correlations with geotechnical indices such as water content,density,shear strength,plastic limit,liquid limit,and plastic index.However,notable disparities in the correlation between grain size parameters and geotechnical indices emerge across different sedimentary environments.

关键词： grain size parameters cluster analysis sedimentary environment correlations geotechnical indexes

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Dominant factors in MiniCone, CPT and pile correlations: A data‐based approach

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Deep Underground Science and Engineering 2023年第4期2卷 346-358页

作者： Seyed Sajad Shirani Abolfazl Eslami Amirhossein Ebrahimipour Moses Karakouzian Department of Civil and Environmental Engineering Amirkabir University of Technology(AUT)(Tehran Polytechnic)TehranIran University of California San Diego San DiegoCaliforniaUSA Department of Civil and Environmental Engineering and Construction University of NevadaLas VegasNevadaUSA

The cone penetration test(CPT)contributes to the design and analysis of piles regarding geometry,installation effect,and pile capacity(shaft and toe resistance).MiniCone,as an alternative to CPT sounding,has been used to carry outﬁeld and laboratory investigations by physical modeling.More tests can be practically carried out through light equipment and small soil mass,involving fewer errors caused by boundary conditions.Furthermore,it can be used for in situ testing,such as quality control,assessment of ground improvement,and subgrade characterization.A database comprising MiniCone and CPT records inﬁeld and physical modeling is proposed with a variety of cone diameters.The case study records in the database have been obtained from 140 tests compiled from data from 26 sources.The sources include the results of 20 physical modelings andﬁeld data from six sites in 10 countries.The data comprise MiniCone and CPT cone tip resistance(qc),and sleeve friction(fs).The different cones are used in sandy,silty sand,and clayey soils via simple chambers(1 g),calibration chambers,and frustum conﬁning vessels.In addition,correlations were found in penetration records in terms of physical modeling types,cone diameters,penetration rates,and soil densities.Moreover,qc and fs are related to capacities of pile toes and shafts using proper correlation coefﬁcients less than unity,respectively.correlations and dominant factors in geotechnical practice between MiniCone,CPT,and pile have been reviewed and discussed.

关键词： correlations CPT database dominant factors MiniCone pile

Critical Heat Flux(CHF)correlations for Subcooled Water Flow Boiling at High Pressure and High Heat Flux

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Journal of Thermal Science 2021年第1期30卷 279-293页

作者： LIU Ping GUO Yusheng DING Wenlong TANG Mingyun SONG Yuntao PENG Xuebing JI Jiadong CHEN Qinghua MAO Xin State Key Laboratory of Mining Response and Disaster Prevention and Control in Deep Coal Mines Anhui University of Science and TechnologyHuainan 232001China School of Mechanical Engineering Anhui University of Science and TechnologyHuainan 232001China Anhui Key Laboratory of Mine Intelligent Equipment and Technology Anhui University of Science and TechnologyHuainan 232001China Institute of Plasma Physics Chinese Academy of SciencesHefei 230031China School of Mining and Safety Engineering Anhui University of Science and TechnologyHuainan 232001China

The subcooled water flow boiling is beneficial for removing the high heat flux from the divertor in the fusion reactor,for which an accurate critical heat flux(CHF)correlation is necessary.Up to now,there are many CHF correlations mentioned for subcooled water flow boiling in the open literatures.However,the CHF correlations’accuracies for the prediction of subcooled water flow boiling are not satisfactory at high heat flux and high pressure for reactor divertor.The present paper compiled 1356 CHF experimental data points from 15 independent open literatures and evaluated 10 existing CHF correlations in subcooled water flow boiling.From the evaluation,the W-2 CHF correlation performs best for the experimental CHF data in all existing critical heat flux correlations.However,the predicted mean absolute error(MAE)of the W-2 correlation is not very ideal for all database and the MAE of the W-2 correlation is from 30%to 50%for some database.In order to enhance the CHF prediction accuracy in subcooled water flow boiling at high heat flux and high pressure,the present paper developed a new CHF correlation.Compared with other existing CHF correlations,the new CHF correlation greatly enhances the prediction accuracy over a broad range of pressures and heat fluxes which are desired in the cooling of high heat flux devices,such as those in the fusion reactor divertor.The validation results show that the new correlation has a MAE of 10.05%and a root mean squared error(RMSE)of 16.61%,predicting 68.1%of the entire database within±10%and 81.5%within±15%.The MAE of the new CHF correlation is 7.4%less than that of the best existing one(W-2 correlation),further confirming its superior prediction accuracy and reliability.Besides,the new CHF correlation works well not only for a uniform power profile but also for a non-uniform power profile in subcooled water flow boiling at high pressure and high heat flux.

关键词： reactor divertor correlations subcooled water flow boiling critical heat flux(CHF) high heat flux high pressure

Exploiting Multiple correlations Among Urban Regions for Crowd Flow Prediction

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Journal of Computer Science & Technology 2020年第2期35卷 338-352页

作者： Qiang Zhou Jing-Jing Gu Chao Ling Wen-Bo Li Yi Zhuang Jian Wang College of Computer Science and Technology Nanjing University of Aeronautics and AstronauticsNanjing 210016China

Crowd flow prediction has become a strategically important task in urban computing,which is the prerequisite for traffic management,urban planning and public safety.However,due to variousness of crowd flows,multiple hidden correlations among urban regions affect the flows.Besides,crowd flows are also influenced by the distribution of Points-of-Interests(POIs),transitional functional zones,environmental climate,and different time slots of the dynamic urban environment.Thus,we exploit multiple correlations between urban regions by considering the mentioned factors comprehensively rather than the geographical distance and propose multi-graph convolution gated recurrent units(MGCGRU)for capturing these multiple spatial correlations.For adapting to the dynamic mobile data,we leverage multiple spatial correlations and the temporal dependency to build an urban flow prediction framework that uses only a little recent data as the input but can mine rich internal modes.Hence,the framework can mitigate the influence of the instability of data distributions in highly dynamic environments for prediction.The experimental results on two real-world datasets in Shanghai show that our model is superior to state-of-the-art methods for crowd flow prediction.

关键词： crowd flow prediction multi-graph convolutional network multiple correlations mining

Effect of system-reservoir correlations on temperature estimation

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Chinese Physics B 2020年第2期29卷 142-147页

作者：朱雯丽吴威罗洪刚 School of Physical Science and Technology&Key Laboratory for Magnetism and Magnetic Materials of the Ministry of Education Lanzhou UniversityLanzhou 730000China Beijing Computational Science Research Center Beijing 100193China

In many previous temperature estimation schemes,the temperature of a sample is directly read out from the final steady state of a quantum probe,which is coupled to the sample.However,in these studies,information of correlations between system(the probe)and reservoir(the sample)is usually eliminated,leading the steady state of the probe is a canonical equilibrium state with respect solely to system's Hamiltonian.To explore the influence of system-reservoir correlations on the estimation precision,we investigate the equilibration dynamics of a spin interacting with a finite temperature bosonic reservoir.By incorporating an intermediate harmonic oscillator or a collective coordinate into the spin,the system-reservoir correlations can be correspondingly encoded in a Gibbs state of an effective Hamilton,which is size consistent with the original bare spin.Extracting information of temperature from this corrected steady state,we find the effect of the system-reservoir correlations on the estimation precision is highly sensitive to the details of the spectral density function of the measured reservoir.

关键词： quantum Fisher information spin-boson model system-reservoir correlations temperature sensing

Quantifying non-classical correlations under thermal effects in a double cavity optomechanical system

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Chinese Physics B 2020年第2期29卷 121-128页

作者： Mohamed Amazioug Larbi Jebli Mostafa Nassik Nabil Habiballah Department of Physics Ecole Normale Supérieure(ENS)Mohammed V University in RabatMorocco LPHE-MS Department of PhysicsFaculty of SciencesMohammed V UniversityRabatMorocco EPTHE Department of PhysicsFaculty of SciencesIbn Zohr UniversityAgadirMorocco Faculty of Applied Sciences Ibn Zohr UniversityAit-MelloulMorocco Abdus Salam International Center for Theoretical Physics Strada Costiera1134151TriesteItaly

We investigate the generation of quantum correlations between mechanical modes and optical modes in an optomechanical system,using the rotating wave approximation.The system is composed of two Fabry-Pérot cavities separated in space;each of the two cavities has a movable end-mirror.Our aim is the evaluation of entanglement between mechanical modes and optical modes,generated by correlations transfer from the squeezed light to the system,using Gaussian intrinsic entanglement as a witness of entanglement in continuous variables Gaussian states,and the quantification of the degree of mixedness of the Gaussian states using the purity.Then,we quantify nonclassical correlations between mechanical modes and optical modes even beyond entanglement by considering Gaussian geometric discord via the Hellinger distance.Indeed,entanglement,mixdness,and quantum discord are analyzed as a function of the parameters characterizing the system(thermal bath temperature,squeezing parameter,and optomechanical cooperativity).We find that,under thermal effect,when entanglement vanishes,purity and quantum discord remain nonzero.Remarkably,the Gaussian Hellinger discord is more robust than entanglement.The effects of the other parameters are discussed in detail.

关键词： cavity optomechanics quantum correlations Gaussian intrinsic entanglement purity Gaussian Hellinger discord Gaussian geometric discord

Mass transfer correlations for membrane gas-solvent contactors undergoing carbon dioxide desorption

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Chinese Journal of Chemical Engineering 2018年第11期26卷 2337-2343页

作者： Colin A.Scholes Shufeng Shen Department of Chemical Engineering The University of Melbourne School of Chemical and Pharmaceutical Engineering Hebei University of Science and Technology

Membrane gas-solvent contactors are a hybrid technology combining solvent absorption with membrane gas separation, which demonstrates potential for CO_2 capture through the ability of the membrane to rigidly control the mass transfer area. Membrane contactors have been successfully demonstrated for CO_2 absorption, and there is strong research interest in using membrane contactors for the complimentary CO_2 desorption process to regenerate the solvent. However, understanding and modelling the various stages of mass transfer in the desorption process is less well-known, given the existing mass transfer correlations had been developed from absorption experiments. Hence, mass transfer correlations for membrane contactors are reviewed here, and their appropriateness for desorption analysed. This is achieved through simulating CO_2 desorption through a membrane contactor from loaded 30 wt% monoethanolamine solvent to enable comparison of the correlations. It was found that the most cited correlations by Yang and Cussler were valid for shell side parallel flow, while that of Kreith and Black was viable for shell side cross flow. A limitation of all of these correlations is that they assume single phase flow on both sides of the membrane; however, the high temperature of CO_2 desorption can lead to partial solvent vaporisation and hence two phases present on one side of the membrane contactor during desorption. A mass transfer correlation is established here for two phase parallel flow on the shell side of a membrane contactor, based on experimental results for three composite and one asymmetric hollow fibre membrane contactors stripping CO_2 from loaded MEA at 105–108 °C. This correlation is comparable to that reported in the literature for mass transfer in other two phase systems, but differs from the standard format for membrane contactors in terms of the exponent on the dimensionless Schmidt and Reynolds numbers.

关键词： Membrane Contactor Carbon dioxide Desorption Two phases Mass transfer correlations

Effects of mean-field and pairing correlations on the Bogoliubov quasiparticle resonance

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Science China(Physics,Mechanics & Astronomy) 2019年第11期62卷 93-101页

作者： XiaoYing Qu Ying Zhang School of Physics and Nuclear Energy Engineering Beihang UniversityBeijing 100191China School of Mechatronics Engineering Guizhou Minzu UniversityGuiyang 550025China Department of Physics School of ScienceTianjin UniversityTianjin 300072China

The quasiparticle resonances are investigated by examining three kinds of quasiparticle spectra, i.e., the density of quasiparticle states, the occupation number density, and the pair number density in the continuum Skyrme Hartree-Fock-Bogoliubov theory with the Green’s function method. Taking the weakly bound nucleus 66Ca as an example, the quasiparticle resonant energies and widths extracted from these three kinds of quasiparticle spectra are compared. For the narrow resonances, the extracted resonant energy and the width are consistent with each other. However, it is difficult to use the density of quasiparticle states to identify the broad resonances due to the background of nonresonant continuum. By switching off the pairing potential and/or the Hartree-Fock(HF) potential respectively in the calculation of these quasiparticle spectra, the roles of HF mean-field and pairing correlations in the quasiparticle resonances are demonstrated clearly. It turns out that all the quasiparticle resonances corresponding to the deeply bound, weakly bound and positive-energy single-particle resonant states, are mainly contributed by the HF potential. The pairing potential helps to slightly increase the resonant energy and the width. However, the pairing potential is important to make the nucleons occupy the low-lying nonresonant continuum states near the threshold and take part in the pairing correlations here,especially for the partial waves with small angular momentum ?.

关键词： quasiparticle resonance mean-field pairing correlations Skyrme Hartree-Fock-Bogoliubov theory Green’s function method

Proposals of SPT-CPT and DPL-CPT correlations for sandy soils in Brazil

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Journal of Rock Mechanics and Geotechnical Engineering 2017年第6期9卷 1152-1158页

作者： Mirella Dalvi dos Santos Kátia Vanessa Bicalho Universidade Federal do Espírito Santo VitóriaBrazil

Field tests in geotechnical engineering are fundamental for identification of the underground conditions.The standard penetration test(SPT) is the most commonly used geotechnical approach. There has been an increase both in the use and application of the in situ tests: cone penetration test(CPT) and dynamic probing(DP). Several empirical SPT-CPT and dynamic probing light(DPL)-CPT correlations for sandy soils have been discussed in the literature. New SPT-CPT and DPL-CPT correlations for the sandy soils of the city of Vitoria, in the southeast of Brazil, are suggested in this paper. Statistical analyses to evaluate the quality of the data used are performed, and the suggested correlations are validated with several previous published datasets. The paper also provides some insights into SPT-CPT correlations and soil characteristics(i.e. the mean particle size and the fines fraction of the soil).

关键词： Standard penetration test(SPT) Cone penetration test(CPT) Dynamic probing light(DPL) correlations Sands Statistical evaluations