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Optimization Model Research on Major Underlying Factors in the Subhealth Condition Evaluation in 1 City and 7 Provinces in China
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作者 Hong-Mei Ni Yu-Min He Xu-Ming Yang 《世界中医药杂志:英文版》 2019年第2期88-94,共7页
Background:The study aimed to analyze major underlying factors of the subhealth condition evaluation and find the optimization model.Methods:Selected 524 cases of health state and 453 cases of subhealth state from the... Background:The study aimed to analyze major underlying factors of the subhealth condition evaluation and find the optimization model.Methods:Selected 524 cases of health state and 453 cases of subhealth state from the research objects.A genetic algorithm was applied to discover the optimization model.The decision tree algorithm was used to find the main performance in the areas of physical,psychological,and social adaptation in the two populations which were the health state and the subhealth state.Conclusions:To establish the optimization model,the author would set up a curve-fitting equation between reduction of health self-assessment score(S-G1)and white blood cell(WBC)value in routine blood,so as to establish the relationship between S-G1 and WBC and found the approximate minimum solution of each equation.Besides,the author would analyze the differences between two populations in WBC examination to seize the difference.Revealed the differences of two populations in the areas of physical,psychological,and social adaptation by data mining and got the result that WBC of"the health state population"was higher than that of"the sub-health state population"in the index changes of WBC.The problem in social adaptation area of the subhealth state population was more serious in degree than the health state population;the reason was complex.If WBC of the health state population was near or below 5.5079,the object may be in the state of subhealth.However,if WBC was near or below 4.35,it is possible to enter the"morbid state." 展开更多
关键词 CURVE fitting decision tree genetic algorithm health state subhealth state white cell COUNT value
Classical Ground State Spin Ordering of the Antiferromagnetic J1-J2 Model
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作者 朱仁贵 《中国物理快报:英文版》 SCIE CAS CSCD 2019年第6期75-78,共4页
The classical frustrated antiferromagnetic J1–J2 model is considered in a description of the classical spin wave for a vector spin system. Its ground state(GS) spin ordering is analyzed by minimizing its energy. Our ... The classical frustrated antiferromagnetic J1–J2 model is considered in a description of the classical spin wave for a vector spin system. Its ground state(GS) spin ordering is analyzed by minimizing its energy. Our analytical derivations show that all the spins in the GS phase must lie in planes that are parallel to each other. When applying the derived formulations to concrete lattices such as the square and simple cubic lattices, we find that in the large J2 region, a large continuous GS degeneracy concluded by a qualitative analysis is lifted, and collinear striped ordering is selected as the GS phase. 展开更多
关键词 CLASSICAL GROUND State SPIN ORDERING ANTIFERROMAGNETIC J1-J2 Model GROUND state(GS)
Neuroimaging characterization of recovery of impaired consciousness in patients with disorders of consciousness 预览
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作者 Sung Ho Jang Young Hyeon Kwon 《中国神经再生研究:英文版》 SCIE CAS CSCD 2019年第7期1202-1207,共6页
Elucidation of critical brain areas or structures that are responsible for recovery of impaired consciousness in patients with disorders of consciousness is important because it can provide information that is useful ... Elucidation of critical brain areas or structures that are responsible for recovery of impaired consciousness in patients with disorders of consciousness is important because it can provide information that is useful when developing therapeutic strategies for neurorehabilitation or neurointervention in patients with disorders of consciousness.In this review,studies that have demonstrated brain changes during recovery of impaired consciousness were reviewed.These studies used positron emission tomography,electroencephalography/transcranial magnetic stimulation,diffusion tensor tractography,and diffusion tensor tractography/electroencephalography.The majority of these studies reported on the importance of supratentorial areas or structures in the recovery of impaired consciousness.The important brain areas or structures that were identified were the prefrontal cortex,basal forebrain,anterior cingulate cortex,and parietal cortex.These results have a clinically important implication that these brain areas or structures can be target areas for neurorehabilitation or neurointervention in patients with disorders of consciousness.However,most of studies were case reports;therefore,further original studies involving larger numbers of patients with disorders of consciousness are warranted.In addition,more detailed information on the brain areas or structures that are relevant to the recovery of impaired consciousness is needed. 展开更多
关键词 CONSCIOUSNESS VEGETATIVE STATE minimally CONSCIOUS STATE ascending RETICULAR activating system diffusion tensor imaging NEUROIMAGING neural regeneration review
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Dppa3 is critical for Lin28a-regulated ES cells na?ve–primed state conversion
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作者 Hui Sang Dan Wang +13 位作者 Shuang Zhao Jinxin Zhang Yan Zhang Jia Xu Xiaoniao Chen Yan Nie Kaiyue Zhang Shuaiqiang Zhang Yuebing Wang Na Wang Fengxia Ma Ling Shuai Zongjin Li Na Liu 《分子细胞生物学报:英文版》 SCIE CAS CSCD 2019年第6期474-488,共15页
Lin28a is a pluripotent factor that promotes somatic cell reprogramming. Unlike other pluripotent factors, Lin28a expression is transient and accumulated in primed embryonic stem (ES) cells, but its exact function and... Lin28a is a pluripotent factor that promotes somatic cell reprogramming. Unlike other pluripotent factors, Lin28a expression is transient and accumulated in primed embryonic stem (ES) cells, but its exact function and mechanism in the conversion of ES cells from naive to primed state remain unclear. Here, we present evidence for Dppa3, a protein originally known for its role in germ cell development, as a downstream target of Lin28a in naive–primed conversion. Using rescue experiment, we demonstrate that Dppa3 functions predominantly downstream of Lin28a during naive–primed state conversion. Higher level of Lin28a prevents let-7 maturation and results in Dnmt3a/b (target of let-7) upregulation, which in turn induces hypermethylation of the Dppa3 promoter. Dppa3 demarcates naive versus primed pluripotency states. These results emphasize that Lin28a plays an important role during the naive–primed state conversion of ES cells, which is partially mediated by a Lin28a–let-7–Dnmt3a/b–Dppa3 axis. 展开更多
关键词 EMBRYONIC STEM cells NAIVE STATE primed STATE METHYLATION Dppa3
A unified theory for sharp dissolution front propagation inchemical dissolution of fluid-saturated porous rocks
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作者 ZHAO ChongBin HOBBS Bruce ORD Alison 《中国科学:技术科学英文版》 SCIE EI CAS CSCD 2019年第1期163-174,共12页
This paper presents a unified theory to deal with when, why and how a sharp acidization dissolution front(ADF), which is represented by the porosity distribution curve, can take place in an acidization dissolution sys... This paper presents a unified theory to deal with when, why and how a sharp acidization dissolution front(ADF), which is represented by the porosity distribution curve, can take place in an acidization dissolution system composed of fluid-saturated porous rocks. The theory contains the following main points:(1) A reaction rate of infinity alone can lead to a sharp ADF of the Stefan-type in the acidization dissolution system. This sharp front is unstable when permeability in the downstream region is smaller than that in the upstream region.(2) For a finite reaction rate, when the acid dissolution capacity number approaches zero,the ADF can have a sharp profile of the Stefan-type either on a much smaller time scale or on a much larger time scale than the dissolution time scale. In the former case, the ADF may become unstable on a much larger time scale than the transport time scale, while in the latter case, it may become unstable if the growth rate of a small perturbation is greater than zero.(3) On the dissolution time scale, even if both the reaction rate is finite and the acid dissolution capacity number approaches zero, the profile of an ADF may not be sharp because it is in a transient state. In this case, not only can an ADF change its profile with time, but also its morphology can grow if the growth rate of a small perturbation is greater than zero. Due to the involvement of both the change rate and the growth rate of the ADF profile, it is necessary to conduct a transient linear stability analysis for determining whether or not a time-dependent ADF is stable in the acidization dissolution system. 展开更多
关键词 SHARP DISSOLUTION FRONT stationary/steady STATE transient STATE acid DISSOLUTION capacity acidization DISSOLUTION porous ROCKS
Enhanced robustness of zero-line modes in graphene via magnetic field
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作者 Ke Wang Tao Hou +1 位作者 Yafei Ren Zhenhua Qiao 《物理学前沿:英文版》 SCIE CSCD 2019年第2期53-58,共6页
We systematically studied the influence of magnetic field on zero-line modes (ZLMs) in graphene and demonstrated the physical origin of their enhanced robustness by employing noneqnilibrium Green's functions and t... We systematically studied the influence of magnetic field on zero-line modes (ZLMs) in graphene and demonstrated the physical origin of their enhanced robustness by employing noneqnilibrium Green's functions and the Landauer Biittiker formula. We found that a perpendicular magnetic field can separate the wavefunctions of the counter-propagating kink states into opposite directions. Specifically, the separation vanishes at the charge neutrality point and increases as the Fermi level deviates from the charge neutrality point and can reach a magnitude comparable to the wavefunction spread at a moderate field strength. Such spatial separation of oppositely propagating ZLMs effectively suppresses backseattering and is more significant under zigzag boundary condition thail under armchair boundary condition. Moreover, the presence of magnetic field enlarges the bulk gap and suppresses the bound states, thereby further reducing the scattering. These mechanisms effectively increase the mean free paths of the ZLMs to approximately 1 |ini in the presence of a disorder. 展开更多
关键词 GRAPHENE TOPOLOGICAL STATE zero-line STATE electronic transport
黑格尔论国家与宗教——《法哲学原理》第270节附释解读
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作者 孙向晨 《学术月刊》 CSSCI 北大核心 2019年第4期17-30,共14页
黑格尔对于国家与宗教的问题有着广泛的论述,尤其在《法哲学原理》第270节的附释中提供了非常集中和成熟的表述,值得我们细细解读。在近代哲学论述政治与宗教的理论框架以及黑格尔国家学说中有关'主观的实体性'论述的双重视野下... 黑格尔对于国家与宗教的问题有着广泛的论述,尤其在《法哲学原理》第270节的附释中提供了非常集中和成熟的表述,值得我们细细解读。在近代哲学论述政治与宗教的理论框架以及黑格尔国家学说中有关'主观的实体性'论述的双重视野下,来解读黑格尔对于国家与宗教之间关系的理论,具有重要的启示意义。在黑格尔的哲学中,国家与宗教有着本体论上的内在联系,但在现实中黑格尔主张防止宗教干涉政治,政教分离,在市民社会的层面管理教会,同时国家对教会与教义采取宽容立场。在此前提下,现代政治的认同需要发挥宗教传统的教化作用,以涵养与培育现代国家正确的'政治情绪'。 展开更多
关键词 国家 宗教 主观的实体性 政治情绪 政教分离 宗教教化
Age-related changes in resting-state functional connectivity in older adults 预览
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作者 Laia Farràs-Permanyer Núria Mancho-Fora +4 位作者 Marc Montalà-Flaquer David Bartrés-Faz Lídia Vaqué-Alcázar Maribel Peró-Cebollero Joan Guàrdia-Olmos 《中国神经再生研究:英文版》 SCIE CAS CSCD 2019年第9期1544-1555,共12页
Age-related changes in the brain connectivity of healthy older adults have been widely studied in recent years,with some differences in the obtained results.Most of these studies showed decreases in general functional... Age-related changes in the brain connectivity of healthy older adults have been widely studied in recent years,with some differences in the obtained results.Most of these studies showed decreases in general functional connectivity,but they also found increases in some particular regions and areas.Frequently,these studies compared young individuals with older subjects,but few studies compared different age groups only in older populations.The purpose of this study is to analyze whole-brain functional connectivity in healthy older adult groups and its network characteristics through functional segregation.A total of 114 individuals,48 to 89 years old,were scanned using resting-state functional magnetic resonance imaging in a resting state paradigm and were divided into six different age groups(<60,60–64,65–69,70–74,75–79,≥80 years old).A partial correlation analysis,a pooled correlation analysis and a study of 3-cycle regions with prominent connectivity were conducted.Our results showed progressive diminution in the functional connectivity among different age groups and this was particularly pronounced between 75 and 79 years old.The oldest group(≥80 years old)showed a slight increase in functional connectivity compared to the other groups.This occurred possibly because of compensatory mechanism in brain functioning.This study provides information on the brain functional characteristics of every age group,with more specific information on the functional progressive decline,and supplies methodological tools to study functional connectivity characteristics.Approval for the study was obtained from the ethics committee of the Comision de Bioetica de la Universidad de Barcelona(approval No.PSI2012-38257)on June 5,2012,and from the ethics committee of the Barcelona’s Hospital Clinic(approval No.2009-5306 and 2011-6604)on October 22,2009 and April 7,2011 respectively. 展开更多
关键词 brain CONNECTIVITY RESTING STATE DEFAULT mode NETWORK aging healthy functional CONNECTIVITY RESTING STATE NETWORK age groups
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Observer-based State Feedback Control to Suppress Stick-slip Vibrations in Oil Well Drill-string 预览
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作者 FU Meng LI Jianghong +2 位作者 WU Yafeng WU Ruobin QIU Wenwei 《国际设备工程与管理:英文版》 2019年第2期65-72,共8页
In drilling field, stick-slip vibrations of the drill-string are the main reason for the failure of the drilling system. To suppress the undesired stick-slip vibrations, an observer-based state feedback control method... In drilling field, stick-slip vibrations of the drill-string are the main reason for the failure of the drilling system. To suppress the undesired stick-slip vibrations, an observer-based state feedback control method is proposed. The drilling system is described by a lumped parameter model including a Karnopp friction torque model. A state observer is designed to estimate the bit velocity in bottom hole and a state feedback controller is proposed to control the top drive velocity. By simulation, the performance of the control algorithm is demonstrated. Based on the control algorithm, a stick-slip vibration control system is developed. Test results show that the control system can effectively eliminate stick-slip vibrations of the drill-string and can be applied to the drilling field. 展开更多
关键词 drill-string STICK-SLIP vibration STATE OBSERVER STATE feedback controller test
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中国民族团结的意涵演化及特色
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作者 严庆 《民族研究》 CSSCI 北大核心 2019年第1期24-34,138,139共13页
团结是人们结成社会共同体和政治共同体的纽带,也是现代社会一个重要的概念与话语。西方社会较早开启了团结的理论化研究,并形成了丰富的理论谱系,强调社会团结是西方社会的重要特点。现代意义上的团结与中国社会及其知识体系交织,衍生... 团结是人们结成社会共同体和政治共同体的纽带,也是现代社会一个重要的概念与话语。西方社会较早开启了团结的理论化研究,并形成了丰富的理论谱系,强调社会团结是西方社会的重要特点。现代意义上的团结与中国社会及其知识体系交织,衍生出中国特色的团结意涵与特色。中国的民族团结是马克思主义民族理论中国化的体现,也是中国特色解决民族问题道路的重要经验,中国的民族团结具有政治团结、社会团结、公民团结的多重维度,这既是由中国民族概念兼具政治、文化、社会的复合意涵所决定的,也是由中国特色的政治社会发展进程所决定的。认知和把握中国民族团结的本质,离不开深刻理解中国共产党的领导和社会主义制度的决定作用。 展开更多
关键词 国家 多民族国家 团结 团结类型 民族团结
Weather induced subtidal flows through multiple inlets of an arctic microtidal lagoon 预览
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作者 Chunyan Li Kevin M.Boswell +2 位作者 Nazanin Chaichitehrani Wei Huang Renhao Wu 《海洋学报:英文版》 SCIE CAS CSCD 2019年第3期1-16,共16页
Estuarine processes in the arctic lagoons are among the least studied but important subjects, especially considering the rapid warming of arctic water which may change the length of ice-free period in the summer. In t... Estuarine processes in the arctic lagoons are among the least studied but important subjects, especially considering the rapid warming of arctic water which may change the length of ice-free period in the summer. In this paper, wind-driven exchange flows in the micro-tidal Elson Lagoon of northern Alaska with multiple inlets of contrasting widths and depths are studied with in situ observations, statistical analysis, numerical experiments, a regression model on the basis of dynamics, and remote sensing data. Water velocity profiles were obtained from a bottom deployed acoustic Doppler current profiler(ADCP) in the northwestern Eluitkak Pass connecting the Beaufort Sea to the Elson Lagoon during a 4.9 day ice-free period in the summer of 2013. The subtidal flow is found correlated with wind(R~2 value ~96%). Frequently occurring east, northeast and north winds from the arctic atmospheric high-and low-pressure systems push water from the Beaufort Sea into the lagoon through the wide inlets on the eastern side of the lagoon, resulting in an outward flow against the wind at the narrow northwestern inlet. The counter-wind flow is a result of an uneven wind forcing acting through the asymmetric inlets and depth,an effect of 'torque' or vorticity. Under northwest wind, the exchange flow at the northwestern inlet reverses its direction, with inward flows through the upwind northwestern inlet and outward flows through the downwind eastern inlets. A regression model is established based on the momentum equations and Taylor series expansions. The model is used to predict flows in July and August of 2015 and July of 2017, supported by available Landsat satellite images. About 73%–80% of the time the flows at Eluitkak Pass are out of Elson Lagoon for the summer of 2015 and 2017. Numerical experiments are conducted to corroborate the findings and illustrate the effects under various wind conditions. A quasi-steady state balance between wind force and surface pressure gradient is confirmed. 展开更多
关键词 WIND-DRIVEN FLOWS MULTIPLE INLETS micro-tidal numerical model experiments counter-wind FLOWS quasi-steady state
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Frameworks of Non-Orthogonal Multiple Access Techniques in Cognitive Radio Communication Systems 预览
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作者 Prabhat Thakur Alok Kumar +2 位作者 S Pandit G Singh S N Satashia 《中国通信:英文版》 SCIE CSCD 2019年第6期129-149,共21页
Recently,the increasing demand of radio spectrum for the next generation communication systems due to the explosive growth of applications appetite for bandwidths has led to the problem of spectrum scarcity.The potent... Recently,the increasing demand of radio spectrum for the next generation communication systems due to the explosive growth of applications appetite for bandwidths has led to the problem of spectrum scarcity.The potential approaches among the proposed solutions to resolve this issue are well explored cognitive radio(CR)technology and recently introduced non-orthogonal multiple access(NOMA)techniques.Both the techniques are employed for efficient spectrum utilization and assure the significant improvement in the spectral efficiency.Further,the significant improvement in spectral efficiency can be achieved by combining both the techniques.Since the CR is well-explored technique as compared to that of the NOMA in the field of communication,therefore it is worth and wise to implement this technique over the CR.In this article,we have presented the frameworks of NOMA implementation over CR as well as the feasibility of proposed frameworks.Further,the differences between proposed CR-NOMA and conventional CR frameworks are discussed.Finally,the potential issues regarding the implementation of CR-NOMA are explored. 展开更多
关键词 COGNITIVE radio channel state information non-orthogonal MULTIPLE ACCESS power division MULTIPLE ACCESS superposition-coding successive-interference-cancellation
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ROCO:Using a Solid State Drive Cache to Improve the Performance of a Host-Aware Shingled Magnetic Recording Drive
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作者 Wen-Guo Liu Ling-Fang Zeng +1 位作者 Dan Feng Kenneth B.Kent 《计算机科学技术学报:英文版》 SCIE EI CSCD 2019年第1期61-76,共16页
Shingled magnetic recording (SMR)can effectively increase the capacity of hard disk drives (HDDs).Hostaware SMR (HA-SMR)is expected to be more popular than other SMR models because of its backward compatibility and ne... Shingled magnetic recording (SMR)can effectively increase the capacity of hard disk drives (HDDs).Hostaware SMR (HA-SMR)is expected to be more popular than other SMR models because of its backward compatibility and new SMR-specific APIs.However,an HA-SMR drive often suffers performance degradation under write-intensive workloads because of frequent non-sequential writes buffered in the disk cache.The non-sequential writes mainly come from update writes,small random writes and out-of-order writes.In this paper,we propose a hybrid storage system called ROCO which aims to use a solid state drive (SSD)cache to improve the performance of an HA-SMR drive.ROCO reorders out-of-order writes belonging to the same zone and uses the SSD cache to absorb update writes and small random writes.We also design a data replacement algorithm called CREA for the SSD cache.CREA first conducts zone-oriented hot/cold data identification to identify cold-cached zones and hot-cached zones,and then evicts data blocks belonging to colder zones with higher priorities that can be sequentially written or written through host-side read-modify-write operations.It gives the lowest priority to data blocks belonging to the hottest-cached zone that have to be non-sequentially written.Experimental results show that ROCO can effectively reduce non-sequential writes to the HA-SMR drive and improve the performance of the HA-SMR drive. 展开更多
关键词 solid state reordering zone-oriented DRIVE (SSD)cache host-aware shingled magnetic recording (HA-SMR)drive zone-oriented block hot/cold DATA identification DATA replacement algorithm
Emergence of superconductivity from fully incoherent normal state in an iron-based superconductor (Ba0.6K0.4)Fe2As2
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作者 Jianwei Huang Lin Zhao +20 位作者 Cong Li Qiang Gao Jing Liu Yong Hu Yu Xu Yongqing Cai Dingsong Wu Ying Ding Cheng Hu Huaxue Zhou Xiaoli Dong Guodong Liu Qingyan Wang Shenjin Zhang Zhimin Wang Fengfeng Zhang Feng Yang Qinjun Peng Zuyan Xu Chuangtian Chen Xingjiang Zhou 《科学通报:英文版》 SCIE EI CSCD 2019年第1期11-19,共9页
In unconventional superconductors,it is generally believed that understanding the physical properties of the normal state is a pre-requisite for understanding the superconductivity mechanism.In conventional supercondu... In unconventional superconductors,it is generally believed that understanding the physical properties of the normal state is a pre-requisite for understanding the superconductivity mechanism.In conventional superconductors like niobium or lead,the normal state is a Fermi liquid with a well-defined Fermi surface and well-defined quasipartcles along the Fermi surface.Superconductivity is realized in this case by the Fermi surface instability in the superconducting state and the formation and condensation of the electron pairs (Cooper pairing).The high temperature cuprate superconductors,on the other hand,represent another extreme case that superconductivity can be realized in the underdoped region where there is neither well-defined Fermi surface due to the pseudogap formation nor quasiparticles near the antinodal regions in the normal state.Here we report a novel scenario that superconductivity is realized in a system with well-defined Fermi surface but without quasiparticles along the Fermi surface in the normal state. High resolution laser-based angle-resolved photoemission measurements have been performed on an optimally-doped iron-based superconductor (Ba0.6K0.4)Fe2As2.We find that,while sharp superconducting coherence peaks emerge in the superconducting state on the hole-like Fermi surface sheets,no quasiparticle peak is present in the normal state.Its electronic behaviours deviate strongly from a Fermi liquid system.The superconducting gap of such a system exhibits an unusual temperature dependence that it is nearly a constant in the superconducting state and abruptly closes at To.These observations have provided a new platform to study unconventional superconductivity in a non-Fermi liquid system. 展开更多
关键词 (Ba0.6K0.4)Fe2As2 ARPES Superconducting gap Normal state Non-Fermi liquid
Remaining Useful Life Prediction of Rolling Element Bearings Based on Different Degradation Stages and Particle Filter 预览
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作者 LI Qing MA Bo LIU Jiameng 《南京航空航天大学学报:英文版》 EI CSCD 2019年第3期432-441,共10页
A method is proposed to improve the accuracy of remaining useful life prediction for rolling element bearings,based on a state space model(SSM)with different degradation stages and a particle filter.The model is impro... A method is proposed to improve the accuracy of remaining useful life prediction for rolling element bearings,based on a state space model(SSM)with different degradation stages and a particle filter.The model is improved by a method based on the Paris formula and the Foreman formula allowing the establishment of different degradation stages.The remaining useful life of rolling element bearings can be predicted by the adjusted model with inputs of physical data and operating status information.The late operating trend is predicted by the use of the particle filter algorithm.The rolling bearing full life experimental data validate the proposed method.Further,the prediction result is compared with the single SSM and the Gamma model,and the results indicate that the predicted accuracy of the proposed method is higher with better practicability. 展开更多
关键词 DIFFERENT LIFE STAGES of state space model REMAINING useful LIFE prediction of ROLLING element bearing particle filter
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Preparation of pseudo-pure states for NMR quantum computing with one ancillary qubit
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作者 Tao Xin Liang Hao +2 位作者 Shi-Yao Hou Guan-Ru Feng Gui-Lu Long 《中国科学:物理学、力学、天文学英文版》 SCIE EI CAS CSCD 2019年第6期13-20,共8页
Quantum state preparation plays an equally important role as quantum operations and measurements in quantum information processing. The previous methods for initialization require either an exponential number of exper... Quantum state preparation plays an equally important role as quantum operations and measurements in quantum information processing. The previous methods for initialization require either an exponential number of experiments, or cause signal reduction or place restrictions on molecular structures. In this study, we propose three types of quantum circuits for preparing the pseudo-pure states of(n-1) qubits in the n-coupled Hilbert space, which simply needs the assistance of one ancilla spin and two different experiments independent of n. Most importantly, our methods work well on homo-nuclear and hetero-nuclear molecules without the reduction of signals in the gradient field. As a proof-of-principle demonstration, we experimentally prepared the pseudo-pure states of heteronuclear 2-qubit and homonuclear 4-qubit molecules using a nuclear magnetic resonance quantum information processor. 展开更多
关键词 QUANTUM state PREPARATION nuclear magnetic RESONANCE QUANTUM ALGORITHMS
Compatibility Evaluation between Direct Coal Liquefaction Residue and Bitumen 预览
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作者 Ji Jie Wu Hao +5 位作者 Xu Ying Suo Zhi Wei Jianming Dai Qingli Zhang Ran Diab Aboelkasim 《中国炼油与石油化工:英文版》 SCIE CAS 2019年第1期90-100,共11页
The compatibility between direct coal liquefaction residue(DCLR) and five kinds of pure bitumen(Shell-90,SK-90, ZSY-70, DM-70 and KLMY-50) was evaluated in this study. The rheological characteristics, glass transition... The compatibility between direct coal liquefaction residue(DCLR) and five kinds of pure bitumen(Shell-90,SK-90, ZSY-70, DM-70 and KLMY-50) was evaluated in this study. The rheological characteristics, glass transition temperatures(T_g), solubility parameters(SP) and SARA(saturates, aromatics, resins, and asphaltenes) fractions of DCLR,five kinds of pure bitumen and their blends(named as DCLR modified bitumen) were measured using the dynamic shear rheometer(DSR), differential scanning calorimetry(DSC), viscosity, and SARA tests, respectively. And the compatibility between DCLR and pure bitumen was characterized with three approaches, viz. the Cole-Cole plot,T_g, and the solubility parameter difference(SPD) method. Since each method has its own working mechanism, the compatibility ranking for the DCLR and five kinds of pure bitumen is slightly different according to the three approaches. However, the difference is pretty close and sometimes can be ignored. The general compatibility ranking decreases in the following order: Shell-90≈SK-90>DM-70≈ZSY-70>KLMY-50, which is affected by the asphaltenes content and the colloid index(I_c) value in the pure bitumen. Pure bitumen with lower asphaltenes content and colloid index(I_c) value has better compatibility with DCLR. 展开更多
关键词 direct coal LIQUEFACTION RESIDUE (DCLR) PURE BITUMEN compatibility Cole-Cole PLOT glass state temperature (Tg) approach SOLUBILITY parameter difference (SPD) method
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Photoelectron imaging of resonance-enhanced multiphoton ionization and above-threshold ionization of ammonia molecules in a strong 800-nm laser pulse
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作者 宋乐乐 孙亚楠 +7 位作者 王艳辉 王晓春 赫兰海 罗嗣佐 胡文惠 佟秋男 丁大军 刘福春 《中国物理B:英文版》 SCIE EI CAS CSCD 2019年第6期140-145,共6页
In this work, we mainly investigate the NH3 molecular multiphoton ionization process by using the photoelectron velocity map imaging technique. Under the condition of femtosecond laser(wavelength at 800 nm), the photo... In this work, we mainly investigate the NH3 molecular multiphoton ionization process by using the photoelectron velocity map imaging technique. Under the condition of femtosecond laser(wavelength at 800 nm), the photoelectron images are detected. The channel switching and above-threshold ionization(ATI) effect are also confirmed. The kinetic energy spectrum(KES) and the photoelectron angular distributions(PADs) are obtained through the anti-Abel transformation from the original images, and then three ionization channels are confirmed successfully according to the Freeman resonance effect in a relatively low laser intensity region. In the excitation process, the intermediate resonance Rydberg states are C~1 A 1(6 + 2 photons process), B~1 E(6 + 2 photons process) and C~1 A 1(7 + 2 photons process), respectively. At the same time, we also find that the photoelectron angular distributions are independent of laser intensity. In addition, the electrons produced by different processes interfere with each other and they can produce a spider-like structure. We also find ac-Stark movement according to the Stark-shift-induced resonance effect when the laser intensity is relatively high. 展开更多
关键词 PHOTOELECTRON imaging RYDBERG state resonance-enhanced MULTIPHOTON IONIZATION PHOTOELECTRON ANGULAR distribution
5G系统终端物理层控制的设计与实现 预览
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作者 李小文 江亚男 李秀 《电子技术应用》 2019年第4期95-99,108共6页
随着5G系统终端物理层处理任务的增加,物理层与高层和底层的交互也大量增加,在原语触发任务的机制下,交互原语混乱导致任务冲突的情况也愈发严重。为了提高交互效率,增强系统的鲁棒性,按照终端开机流程将物理层分为了空态、小区选择态... 随着5G系统终端物理层处理任务的增加,物理层与高层和底层的交互也大量增加,在原语触发任务的机制下,交互原语混乱导致任务冲突的情况也愈发严重。为了提高交互效率,增强系统的鲁棒性,按照终端开机流程将物理层分为了空态、小区选择态、空闲态、随机接入态和连接态,并设计各状态下物理层任务,通过物理层控制实现对状态及任务的调度,完成与高层和底层的交互,实现终端与基站的正常通信。在5G的TDD制式、80 MHz带宽、子载波间隔为30 kHz等参数配置下,终端物理层可以完成正确的解调或译码,同时能够判断出异常情况并且拒绝处理。 展开更多
关键词 5G系统 物理层 状态 控制 流程
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Suitable resolution of EOS tables for neutron star investigations
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作者 陈厚源 文德华 张娜 《中国物理C:英文版》 SCIE CAS CSCD 2019年第5期93-98,共6页
Inasmuch as the hydrostatic structure of the interior of neutron stars uniquely depends on the equation of state(EOS), the inverse constraints on EOS from astrophysical observations have been an important method for r... Inasmuch as the hydrostatic structure of the interior of neutron stars uniquely depends on the equation of state(EOS), the inverse constraints on EOS from astrophysical observations have been an important method for revealing the properties of high density matter. Currently, most EOS for neutron star matter are given in tabular form,but these numerical tables can have quite different resolution. To guarantee both the accuracy and efficiency in computing the Tolman-Oppenheimer-Volkoff equations, a concise standard for generating EOS tables with suitable resolution is investigated. It is shown that EOS tables with 50 points logarithmic-uniformly distributed in the supra-nuclear density segment [ρ0, 10ρ0], where ρ0 is the nuclear saturation density, correspond to the interpolation induced errors of ~0.02% for the gravitational mass M and ~0.2% for the tidal deformability ∧. 展开更多
关键词 NEUTRON star equation of state TOV EQUATIONS
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