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Photoinduced Floquet higher-order Weyl semimetal in C_(6) symmetric Dirac semimetals
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作者 许欣欣 王梓名 +1 位作者 许东辉 陈垂针 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第6期109-117,共9页
Topological Dirac semimetals are a parent state from which other exotic topological phases of matter, such as Weyl semimetals and topological insulators, can emerge. In this study, we investigate a Dirac semimetal pos... Topological Dirac semimetals are a parent state from which other exotic topological phases of matter, such as Weyl semimetals and topological insulators, can emerge. In this study, we investigate a Dirac semimetal possessing sixfold rotational symmetry and hosting higher-order topological hinge Fermi arc states, which is irradiated by circularly polarized light. Our findings reveal that circularly polarized light splits each Dirac node into a pair of Weyl nodes due to the breaking of time-reversal symmetry, resulting in the realization of the Weyl semimetal phase. This Weyl semimetal phase exhibits rich boundary states, including two-dimensional surface Fermi arc states and hinge Fermi arc states confined to six hinges.Furthermore, by adjusting the incident direction of the circularly polarized light, we can control the degree of tilt of the resulting Weyl cones, enabling the realization of different types of Weyl semimetals. 展开更多
关键词 Dirac semimetals Weyl semimetals periodic driving higher-order topology
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Pipeline thickness estimation using the dispersion of higher-order SH guided waves
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作者 代政辰 刘金霞 +3 位作者 龙云飞 张建海 Tribikram Kundu 崔志文 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第7期389-396,共8页
Thickness measurement plays an important role in the monitoring of pipeline corrosion damage. However, the requirement for prior knowledge of the shear wave velocity in the pipeline material for popular ultrasonic thi... Thickness measurement plays an important role in the monitoring of pipeline corrosion damage. However, the requirement for prior knowledge of the shear wave velocity in the pipeline material for popular ultrasonic thickness measurement limits its widespread application. This paper proposes a method that utilizes cylindrical shear horizontal(SH) guided waves to estimate pipeline thickness without prior knowledge of shear wave velocity. The inversion formulas are derived from the dispersion of higher-order modes with the high-frequency approximation. The waveform of the example problems is simulated using the real-axis integral method. The data points on the dispersion curves are processed in the frequency domain using the wave-number method. These extracted data are then substituted into the derived formulas. The results verify that employing higher-order SH guided waves for the evaluation of thickness and shear wave velocity yields less than1% error. This method can be applied to both metallic and non-metallic pipelines, thus opening new possibilities for health monitoring of pipeline structures. 展开更多
关键词 pipeline wall thickness higher-order modes SH guided waves DISPERSION
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Higher-order expansions of powered extremes of logarithmic general error distribution
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作者 TAN Xiao-feng LI Li-hui 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2024年第1期47-54,共8页
In this paper,Let M_(n)denote the maximum of logarithmic general error distribution with parameter v≥1.Higher-order expansions for distributions of powered extremes M_(n)^(p)are derived under an optimal choice of nor... In this paper,Let M_(n)denote the maximum of logarithmic general error distribution with parameter v≥1.Higher-order expansions for distributions of powered extremes M_(n)^(p)are derived under an optimal choice of normalizing constants.It is shown that M_(n)^(p),when v=1,converges to the Frechet extreme value distribution at the rate of 1/n,and if v>1 then M_(n)^(p)converges to the Gumbel extreme value distribution at the rate of(loglogn)^(2)=(log n)^(1-1/v). 展开更多
关键词 logarithmic general error distribution convergence rate higher-order expansion powered ex-treme
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Opinion consensus incorporating higher-order interactions in individual-collective networks
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作者 叶顺 涂俐兰 +2 位作者 王先甲 胡佳 王薏潮 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第7期105-115,共11页
In the current information society, the dissemination mechanisms and evolution laws of individual or collective opinions and their behaviors are the research hot topics in the field of opinion dynamics. First, in this... In the current information society, the dissemination mechanisms and evolution laws of individual or collective opinions and their behaviors are the research hot topics in the field of opinion dynamics. First, in this paper, a two-layer network consisting of an individual-opinion layer and a collective-opinion layer is constructed, and a dissemination model of opinions incorporating higher-order interactions(i.e. OIHOI dissemination model) is proposed. Furthermore, the dynamic equations of opinion dissemination for both individuals and groups are presented. Using Lyapunov's first method,two equilibrium points, including the negative consensus point and positive consensus point, and the dynamic equations obtained for opinion dissemination, are analyzed theoretically. In addition, for individual opinions and collective opinions,some conditions for reaching negative consensus and positive consensus as well as the theoretical expression for the dissemination threshold are put forward. Numerical simulations are carried to verify the feasibility and effectiveness of the proposed theoretical results, as well as the influence of the intra-structure, inter-connections, and higher-order interactions on the dissemination and evolution of individual opinions. The main results are as follows.(i) When the intra-structure of the collective-opinion layer meets certain characteristics, then a negative or positive consensus is easier to reach for individuals.(ii) Both negative consensus and positive consensus perform best in mixed type of inter-connections in the two-layer network.(iii) Higher-order interactions can quickly eliminate differences in individual opinions, thereby enabling individuals to reach consensus faster. 展开更多
关键词 two-layer social networks individual and collective opinions higher-order interactions CONSENSUS Lyapunov's first method
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Thermodynamics in a quantum corrected Reissner-Nordstr?m-AdS black hole and its GUP-corrections
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作者 宋建君 刘成周 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第4期345-353,共9页
We calculate the thermodynamic quantities in the quantum corrected Reissner-Nordstr?m-AdS(RN-AdS)black hole,and examine their quantum corrections.By analyzing the mass and heat capacity,we give the critical state and ... We calculate the thermodynamic quantities in the quantum corrected Reissner-Nordstr?m-AdS(RN-AdS)black hole,and examine their quantum corrections.By analyzing the mass and heat capacity,we give the critical state and the remnant state,respectively,and discuss their consistency.Then,we investigate the quantum tunneling from the event horizon of massless scalar particle by using the null geodesic method,and charged massive boson W^(±)and fermions by using the Hamilton-Jacob method.It is shown that the same Hawking temperature can be obtained from these tunneling processes of different particles and methods.Next,by using the generalized uncertainty principle(GUP),we study the quantum corrections to the tunneling and the temperature.Then the logarithmic correction to the black hole entropy is obtained. 展开更多
关键词 black hole thermodynamics quantum corrections quantum tunneling generalized uncertainty principle
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A Study of a Moral Dilemma Stories Teaching Model Focusing on the Development of Higher-Order Thinking --"Synthetic polymers" as an example
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作者 Lin Tang Yi Dai 《教育技术与创新》 2024年第1期27-35,共9页
Cultivating students'higher-order thinking is one of the important goals of modern education,and innovative teaching model is an effective way to achieve this goal.Aiming at the inadequacy of the existing moral di... Cultivating students'higher-order thinking is one of the important goals of modern education,and innovative teaching model is an effective way to achieve this goal.Aiming at the inadequacy of the existing moral dilemma stories approach in the transformation of knowledge and behavior,this research constructs a new Project Based Learning-Ethical Dilemma Stories(PBL-EDS)Teaching Model applicable to China's secondary education stage based on the innovative features of the moral dilemma stories approach on the core competencies,taking the chemistry subject as an example to carry out practice,and puts forward suggestions for the implementation of the teaching model.Chemistry as an example to carry out the practice,and suggestions are made for the implementation of the teaching model. 展开更多
关键词 higher-order thinking moral dilemma stories teaching model secondary education
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Higher-Order Corrections to Earth's Ionosphere Shocks
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作者 H.G.Abdelwahed E.K.El-Shewy 《Communications in Theoretical Physics》 SCIE CAS CSCD 2017年第1期90-96,共7页
Nonlinear shock wave structures in unmagnetized collisionless viscous plasmas composed fluid of positive(negative) ions and nonthermally electron distribution are examined. For ion shock formation, a reductive perturb... Nonlinear shock wave structures in unmagnetized collisionless viscous plasmas composed fluid of positive(negative) ions and nonthermally electron distribution are examined. For ion shock formation, a reductive perturbation technique applied to derive Burgers equation for lowest-order potential. As the shock amplitude decreasing or enlarging,its steepness and velocity deviate from Burger equation. Burgers type equation with higher order dissipation must be obtained to avoid this deviation. Solution for the compined two equations has been derived using renormalization analysis. Effects of higher-order, positive- negative mass ratio Q, electron nonthermal parameter δ and kinematic viscosities coefficient of positive(negative) ions η1 and η2 on the electrostatic shocks in Earth's ionosphere are also argued. 展开更多
关键词 nonthermal electrons ion shock waves Burgers equation Burger type equation renormalization method higher-order dissipation
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Study of the effects on GPS coordinate time series caused by higher-order ionospheric corrections calculated using the DIPOLE model
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作者 Liansheng Deng Weiping Jiang +2 位作者 Hua Chen Zhaohan Zhu Wen Zhao 《Geodesy and Geodynamics》 2017年第2期111-119,共9页
As one of the main error sources in high-precision Global Positioning System (GPS) data processing, higher-order ionospheric (HOI) delays cause significant effects on coordinate time series that cannot be ignored ... As one of the main error sources in high-precision Global Positioning System (GPS) data processing, higher-order ionospheric (HOI) delays cause significant effects on coordinate time series that cannot be ignored in analyses of long time series. Typically two geomagnetic models, DIPOLE model and Inter- national Geomagnetic Reference Field (IGRF) model, are used for calculating HOI corrections. This paper investigates the effects of HOI correction caused by the DIPOLE model on coordinate time series. GPS data from 104 globally distributed International GNSS Service (IGS) stations spanning from January, 1999 to December, 2003 were reprocessed following up-to-date processing strategies utilizing GAMIT and GLOBK software. Two coordinate time series solutions before and after applying HOI corrections using the DIPOLE model were derived for studying the effects in terms of seasonal variations and noise amplitudes. The results show that after applying the HOI corrections calculated with DIPOLE, the noise amplitudes of the coordinate time series increased, especially in the north and east directions, and the increased amplitudes of the flicker noise were larger than those of the white noise. Furthermore, spurious periodic signals that were probably introduced by the HOI corrections from the DIPOLE model were also found. Moreover, an apparent increase was confirmed for the power spectra of most of the stations, especially in the north direction, and the amplitudes of both the annual and semi-annual signals also increased in the north and east directions. It can be inferred that the quality of the external data sources such as the geomagnetic model might be the key factors that lead to the above results. The results also suggest that we should be very careful when the DIPOLE model is used for HOI corrections. 展开更多
关键词 Fhigher-order ionospheric corrections Coordinate time series Periodic characteristics Noise amplitudes
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Correction:Nanomaterial-Based Repurposing of Macrophage Metabolism and Its Applications 被引量:1
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作者 Tingting Meng Danfeng He +7 位作者 Zhuolei Han Rong Shi Yuhan Wang Bibo Ren Cheng Zhang Zhengwei Mao Gaoxing Luo Jun Deng 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第12期357-357,共1页
Following publication of the original article[1],the authors reported an error in the last author’s name,it was mistakenly written as“Jun Den”.The correct author’s name“Jun Deng”has been updated in this Correction.
关键词 MISTAKE correct correctION
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Influence of higher-order ionospheric delay correction on GPS precise orbit determination and precise positioning 被引量:6
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作者 Zhimin Liu Yangyang Li +1 位作者 Jinyun Guo Fei Li 《Geodesy and Geodynamics》 2016年第5期369-376,共8页
At present, Global Navigation Satellite Systems(GNSS) users usually eliminate the influence of ionospheric delay of the first order items by dual-frequency ionosphere-free combination. But there is still residual io... At present, Global Navigation Satellite Systems(GNSS) users usually eliminate the influence of ionospheric delay of the first order items by dual-frequency ionosphere-free combination. But there is still residual ionospheric delay error of higher order term. The influence of the higher-order ionospheric corrections on both GPS precision orbit determination and static Precise Point Positioning(PPP) are studied in this paper. The influence of higher-order corrections on GPS precision orbit determination, GPS observations and static PPP are analyzed by neglecting or considering the higher-order ionospheric corrections by using a globally distributed network which is composed of International GNSS Service(IGS) tracking stations. Numerical experimental results show that, the root mean square(RMS) in three dimensions of satellite orbit is 36.6 mme35.5 mm. The maximal second-order ionospheric correction is 9 cm, and the maximal third-order ionospheric correction is 1 cm. Higher-order corrections are influenced by latitude and station distribution. PPP is within 3 mm in the directions of east and up. Furthermore, the impact is mainly visible in the direction of north, showing a southward migration trend, especially at the lower latitudes where the influence value is likely to be bigger than 3 mm. 展开更多
关键词 higher-order ionosphere Precision orbit determination PPP Geomagnetic model
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The application of the strip-shaped cymba conchae orthosis in the nonsurgical correction of complex auricular deformity 被引量:1
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作者 Huijuan Xu Shaoguang Ding +6 位作者 Fei Zhang Zhifeng Zhang Xiangyu Chen Mingyang Li Haitao Yang Fugen Han Hongjian Liu 《Journal of Otology》 CAS CSCD 2024年第1期24-29,共6页
Objective: This study aims to evaluate the efficacy and safety of using a strip-shaped cymba conchae orthosis for the nonsurgical correction of complex auricular deformities. Methods: Clinical data were collected from... Objective: This study aims to evaluate the efficacy and safety of using a strip-shaped cymba conchae orthosis for the nonsurgical correction of complex auricular deformities. Methods: Clinical data were collected from 2020 to 2021 for 6 patients who underwent correction using a stripshaped cymba conchae orthosis. The indications, corrective effects, and complications associated with use of the orthosis were analyzed. Results: There were four indications for treatment: cryptotia with helix adhesion;cryptotia with grade I microtia;cryptotia with excessive helix thickness;and auricular deformity beyond the treatment time window(≥6 months). Excellent corrective effects were observed in all 6 patients. Complications occurred in one patient, who recovered after symptomatic treatment. Conclusion: The use of a strip-shaped cymba conchae orthosis alone or combined with a U-shaped helix orthosis presents a feasible approach for correcting complex auricular deformities or deformities beyond the treatment time window in pediatric patients. 展开更多
关键词 Cymba conchae Auricular deformity Cryptotia Nonsurgical correction ORTHOSIS
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High-order corrections to the radiation-free dynamics of an electron in the strongly radiation-dominated regime
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作者 A.S.Samsonov E.N.Nerush I.Yu.Kostyukov 《Matter and Radiation at Extremes》 SCIE EI CAS CSCD 2023年第1期8-19,共12页
A system of reduced equations is proposed for electron motion in the strongly radiation-dominated regime for an arbitrary electromagnetic field configuration.The approach developed here is used to analyze various scen... A system of reduced equations is proposed for electron motion in the strongly radiation-dominated regime for an arbitrary electromagnetic field configuration.The approach developed here is used to analyze various scenarios of electron dynamics in this regime:motion in rotating electric and magnetic fields and longitudinal acceleration in a plane wave and in a plasma wakefield.The results obtained show that this approach is able to describe features of electron dynamics that are essential in certain scenarios,but cannot be captured in the framework of the original radiation-free approximation[Samsonov et al.,Phys.Rev.A 98,053858(2018)and A.Gonoskov and M.Marklund,Phys.Plasmas 25,093109(2018)].The results are verified by numerical integration of the nonreduced equations of motion with account taken of radiation reaction in both semiclassical and fully quantum cases. 展开更多
关键词 field DYNAMICS correction
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采用B1-corrected variable-flip-angle(VFA)的定量动态增强MRI在乳腺良恶性病变的研究` 被引量:1
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作者 蒋辉 曲金荣 +3 位作者 宋颖 王立峰 刘翠翠 张宏凯 《中国CT和MRI杂志》 2024年第1期85-87,共3页
目的探讨采用B1-corrected VFA技术的定量动态增强(Dynamic Contrast Enhancement,DCE)MRI在乳腺良恶性鉴别诊断中的价值。方法前瞻性研究本院63例乳腺疾病患者,行3.0 T DCE-MR检查,结合B1-corrected VFA技术获得T1值,在此基础上计算出D... 目的探讨采用B1-corrected VFA技术的定量动态增强(Dynamic Contrast Enhancement,DCE)MRI在乳腺良恶性鉴别诊断中的价值。方法前瞻性研究本院63例乳腺疾病患者,行3.0 T DCE-MR检查,结合B1-corrected VFA技术获得T1值,在此基础上计算出DCE-MRI定量参数:容量转移常数(Ktrans)、速率常数(Kep)和血管外细胞外间隙容积比(Ve),对乳腺恶性、良性及正常腺体组获得的定量参数行Kruskal-Wallis检验;最后绘制ROC(receiver operating characteristic curve,ROC)曲线。结果恶性肿瘤组Ktrans、Kep、Ve中位数(最小值最大值)分别为0.010(0.0010.118)min-1、0.145(0.0020.863)min-1、0.058(0.0020.611);良性病变组Ktrans、Kep、Ve中位数为0.238(0.0090.740)min-1、0.365(0.0201.012)min-1、0.517(01810.923);正常腺体组Ktrans、Kep、Ve中位数为0.812(0.1212.352)min-1、1.147(0.3282.363)min-1、0.712(0.4041.183)。Kruskal-Wallis检验显示三组间Ktrans、Kep、Ve P<0.05,均有统计学意义;良恶性组间、恶性与正常组间的Ktrans、Kep、Ve差异有统计学意义,而良性和正常组之间的Ve值无统计学意义。三者AUC分别为0.875、0.957、0.707,三者判断乳腺良恶性变的Ktrans、Kep、Ve敏感度分别为93.8%、97.9%、45.8%;特异度分别为66.7%、86.73%、86.7%。结论结合B1-corrected VFA序列测量的3.0T DCE-MRI参数Ktrans、Kep、Ve可以反映乳腺良恶性病变的血流灌注特征,可用于乳腺病变良恶性的鉴别诊断。 展开更多
关键词 乳腺 B1-corrected VFA 动态增强磁共振成像
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Adaptation analysis and fusion correction method of CMIP6 precipitation simulation data on the Qinghai-Tibetan Plateau
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作者 PENG Hao QIN Dahui +3 位作者 WANG Zegen ZHANG Menghan YANG Yanmei YONG Zhiwei 《Journal of Mountain Science》 SCIE CSCD 2024年第2期555-573,共19页
In order to obtain more accurate precipitation data and better simulate the precipitation on the Tibetan Plateau,the simulation capability of 14 Coupled Model Intercomparison Project Phase 6(CMIP6)models of historical... In order to obtain more accurate precipitation data and better simulate the precipitation on the Tibetan Plateau,the simulation capability of 14 Coupled Model Intercomparison Project Phase 6(CMIP6)models of historical precipitation(1982-2014)on the Qinghai-Tibetan Plateau was evaluated in this study.Results indicate that all models exhibit an overestimation of precipitation through the analysis of the Taylor index,temporal and spatial statistical parameters.To correct the overestimation,a fusion correction method combining the Backpropagation Neural Network Correction(BP)and Quantum Mapping(QM)correction,named BQ method,was proposed.With this method,the historical precipitation of each model was corrected in space and time,respectively.The correction results were then analyzed in time,space,and analysis of variance(ANOVA)with those corrected by the BP and QM methods,respectively.Finally,the fusion correction method results for each model were compared with the Climatic Research Unit(CRU)data for significance analysis to obtain the trends of precipitation increase and decrease for each model.The results show that the IPSL-CM6A-LR model is relatively good in simulating historical precipitation on the Qinghai-Tibetan Plateau(R=0.7,RSME=0.15)among the uncorrected data.In terms of time,the total precipitation corrected by the fusion method has the same interannual trend and the closest precipitation values to the CRU data;In terms of space,the annual average precipitation corrected by the fusion method has the smallest difference with the CRU data,and the total historical annual average precipitation is not significantly different from the CRU data,which is better than BP and QM.Therefore,the correction effect of the fusion method on the historical precipitation of each model is better than that of the QM and BP methods.The precipitation in the central and northeastern parts of the plateau shows a significant increasing trend.The correlation coefficients between monthly precipitation and site-detected precipitation for all models after BQ correction exceed 0.8. 展开更多
关键词 GCM CMIP6 Precipitation correction BP-QM fusion correction Spatio-temporal characteristics
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Correction: Surface Patterning of Metal ZincElectrode with an In-Region Zincophilic Interfacefor High-Rate and Long-Cycle-Life Zinc MetalAnode
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作者 Tian Wang Qiao Xi +8 位作者 Kai Yao Yuhang Liu Hao Fu Venkata Siva Kavarthapu Jun Kyu Lee Shaocong Tang Dina Fattakhova-Rohlfing Wei Ai Jae Su Yu 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第7期456-457,共2页
Correction to:Nano-Micro Letters(2024)16:112 https://doi.org/10.1007/s40820-024-01327-2 In the supplementary information the following corrections have been carried out:1.Institute of Energy and Climate Research,Mater... Correction to:Nano-Micro Letters(2024)16:112 https://doi.org/10.1007/s40820-024-01327-2 In the supplementary information the following corrections have been carried out:1.Institute of Energy and Climate Research,Materials Synthesis and Processing,Forschungszentrum Jülich GmbH,52425 Jülich,Germany.Corrected:Institute of Energy and Climate Research:Materials Synthesis and Processing(IEK-1),Forschungszentrum Jülich GmbH,52425 Jülich,Germany. 展开更多
关键词 correctION ZINC ELECTRODE
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Author Correction:Recent Progress in Interfacial Dipole Engineering for Perovskite Solar Cells
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作者 Yinyi Ma Jue Gong +1 位作者 Peng Zeng Mingzhen Liu 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第9期500-500,共1页
In the version of this Article originally published online,there was an error in the schematics of Figures 2b and 2c.These errors have now been corrected in the original article.
关键词 corrected ERROR Solar
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Author Correction to “Enhanced Property of Thin Cuprous Oxide Film Prepared through Green Synthetic Route”
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作者 Achraf El Kasmi Henning Vieker +3 位作者 Ling-nan Wu AndréBeyer Tarik Chafik Zhenyu Tian 《Chinese Journal of Chemical Physics》 SCIE EI CAS CSCD 2024年第4期571-571,共1页
This correction adds some information to our publication[Chin.J.Chem.Phys.32,365–372(2019)]that we previously missed to include.Our previous work published in[Appl.Catal.B Env-iron.186,10(2016)]was based on the same ... This correction adds some information to our publication[Chin.J.Chem.Phys.32,365–372(2019)]that we previously missed to include.Our previous work published in[Appl.Catal.B Env-iron.186,10(2016)]was based on the same sample series but with the focus of explaining the interplay between the catalytic behavior and properties of the cuprous thin films.A superior catalytic performance was demonstrated when water was added in the deposition process[1](see Ref.[47]in our publication corrected here). 展开更多
关键词 films. CATALYTIC correctION
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Correction to:Error Calculation of Large-Amplitude Internal Solitary Waves Within the Pycnocline Introduced by the Strong Stratification Approximation
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作者 Cunguo Xu Zhan Wang Masoud Hayatdavoodi 《哈尔滨工程大学学报(英文版)》 CSCD 2024年第1期247-247,共1页
In the original publication the third author name is published incorrectly as“Hayatdavoodi Masoud”.The correct author name should be read as“Masoud Hayatdavoodi”.The correct author name is available in this correc... In the original publication the third author name is published incorrectly as“Hayatdavoodi Masoud”.The correct author name should be read as“Masoud Hayatdavoodi”.The correct author name is available in this correction. 展开更多
关键词 STRONG Internal correctION
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Corrective-Net:面向多标签文本分类的标签关联学习模块
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作者 肖新正 黄瑞章 +3 位作者 陈艳平 秦永彬 宋玉梅 周裕林 《计算机工程与科学》 CSCD 北大核心 2024年第6期1092-1100,共9页
在目前的多标签文本分类任务中,主要面临以下2个问题:(1)侧重文本表示学习,对标签之间的关联信息建模不充分;(2)尽管使用了标签关联信息来改善多标签分类任务,但对标签关联的建模过于依赖人工预定义的外部知识,而外部知识的获取成本高昂... 在目前的多标签文本分类任务中,主要面临以下2个问题:(1)侧重文本表示学习,对标签之间的关联信息建模不充分;(2)尽管使用了标签关联信息来改善多标签分类任务,但对标签关联的建模过于依赖人工预定义的外部知识,而外部知识的获取成本高昂,限制了其实际应用。针对以上问题,提出了一种面向多标签文本分类的标签关联学习模块Corrective-Net。该模块可以在不依赖外部知识的前提下,自动学习数据中的标签关联信息;同时,它还可以利用标签关联信息,对基础分类模块的初始预测结果进行修正,使得最终预测兼顾语义信息和标签关联信息,以获得更精准的多标签预测结果。在AAPD和SO数据集上的大量实验表明,Corrective-Net具有通用性和有效性,通过分析标签修正对各个标签性能的影响,得到了显式的标签关联信息,并进行了可视化。 展开更多
关键词 标签关联 标签修正 多标签 文本分类 可视化
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Using WGM2012 to Compute Gravity Anomaly Corrections of Leveling Observations in China
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作者 Yanhui CAI Li ZHANG Xu MA 《Journal of Geodesy and Geoinformation Science》 CSCD 2023年第1期88-94,共7页
Gravity Anomaly Correction(GAC)is a very important term in leveling data processing.In most cases,it is troublesome for field surveyors to measure gravity when leveling.In this paper,based on the complete Bouguer Grav... Gravity Anomaly Correction(GAC)is a very important term in leveling data processing.In most cases,it is troublesome for field surveyors to measure gravity when leveling.In this paper,based on the complete Bouguer Gravity Anomaly(BGA)map of WGM2012,the feasibility of replacing in-situ gravity surveying in China is investigated.For leveling application,that is to evaluate the accuracy of WGM2012 in China.Because WGM2012 is organized with a standard rectangle grid,two interpolation methods,bilinear interpolating and Inverse Distance Weighted(IDW)interpolating,are proposed.Four sample areas in China,i.e.,Hanzhong,Chengdu,Linzhi and Shantou,are selected to evaluate the systems bias and precision of WGM2012.Numerical results show the average system bias of WGM2012 BGA in west China is about-100.1 mGal(1 mGal=10^(-5) m/s^(2))and the standard deviation is about 30.7 mGal.Tests in Shantou indicate the system bias in plain areas is about-130.4 mGal and standard deviation is about 6.8 mGal.All these experiments means the accuracy of WGM2012 is limited in high mountain areas of western China,but in plain areas,such as Shantou,WGM2012 BGA map is quite good for most leveling applications after calibrating the system bias. 展开更多
关键词 Bouguer Gravity Anomaly(BGA) Gravity Anomaly correction(GAC) precise leveling WGM2012 bilinear Interpolation Inverse Distance Weighted(IDW)interpolation
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