通讯机构：
[Li, N ] H;Hunan City Univ, Coll Informat & Elect Engn, Yiyang 413000, Peoples R China.
关键词：
multiview data clustering;unsupervised feature selection;similarity graph
摘要：
In multiview data clustering, consistent or complementary information in the multiview data can achieve better clustering results. However, the high dimensions, lack of labeling, and redundancy of multiview data certainly affect the clustering effect, posing a challenge to multiview clustering. A clustering algorithm based on multiview feature selection clustering (MFSC), which combines similarity graph learning and unsupervised feature selection, is designed in this study. During the MFSC implementation, local manifold regularization is integrated into similarity graph learning, with the clustering label of similarity graph learning as the standard for unsupervised feature selection. MFSC can retain the characteristics of the clustering label on the premise of maintaining the manifold structure of multiview data. The algorithm is systematically evaluated using benchmark multiview and simulated data. The clustering experiment results prove that the MFSC algorithm is more effective than the traditional algorithm.
期刊：
Moscow University Physics Bulletin,2023年78(2):145-148 ISSN：0027-1349
通讯作者：
Zhou, J
作者机构：
[Deng, Ying; Leng, Xiaoling; Zhou, Jing; Zhou, J] Hunan City Univ, Dept Phys, Yiyang 413000, Hunan, Peoples R China.;[Deng, Ying; Leng, Xiaoling; Zhou, Jing; Zhou, J] Hunan City Univ, All Solid State Energy Storage Mat & Devices Key L, Yiyang 413000, Peoples R China.
通讯机构：
[Zhou, J ] H;Hunan City Univ, Dept Phys, Yiyang 413000, Hunan, Peoples R China.;Hunan City Univ, All Solid State Energy Storage Mat & Devices Key L, Yiyang 413000, Peoples R China.
摘要：
The partition functions of Jackiw–Teitelboim (JT) gravity corresponds to random matrix integral. And we can define three different versions of bosonic JT gravity which are dual to matrix integrals of GUE, GOE, and GSE, respectively. In fact, the largest eigenvalue
$$\lambda_{\textrm{max}}$$
of the Gaussian unitary random matrix GUE is described by the Tracy–Widom distribution. Then we show that there is a third-order order phase transition in the JT gravity as
$$\lambda_{\textrm{max}}$$
crosses its mean value from left weakly coupled tail to right strongly coupled tail.
作者机构：
[Wang, Xingyu; Tan, Weishi] Nanjing Univ Sci & Technol, Sch Sci, Nanjing 210094, Peoples R China.;[Ma, Chunlin] Huaiyin Normal Univ, Sch Phys & Elect Elect Engn, Huaian 223001, Peoples R China.;[Zhou, Weiping] Nanchang Univ, Sch Mat Sci & Engn, Nanchang 330031, Jiangxi, Peoples R China.;[Tan, Weishi] Hunan City Univ, Coll Informat & Elect Engn, All Solid State Energy Storage Mat & Devices Key, Yiyang 413002, Peoples R China.
通讯机构：
[Weishi Tan] S;School of Science, Nanjing University of Science and Technology, Nanjing 210094, China<&wdkj&>All-Solid-State Energy Storage Materials and Devices Key Laboratory of Hunan Province, College of Information and Electronic Engineering, Hunan City University, Yiyang 413002, China
摘要：
Abstract: Samples of (110), (100), and (111) MgO single crystals were implanted with 70 keV N ions at room temperature. All as-implanted samples showed room temperature hysteresis in magnetization loops. The observed saturation magnetization (Ms) was 0.79 × 10−4 emu/g, 1.28 × 10−4 emu/g, and 1.5 × 10−4 emu/g for (110), (100) and (111) orientation implanted-MgO and follows the relation Ms(111) > Ms(100) > Ms(110), indicative of crystalline orientation-dependent ferromagnetism in N-implanted MgO. The samples were characterized by X-ray photoelectron spectroscopy (XPS), high resolution X-ray diffraction (HRXRD), reciprocal space mapping (RSM), and photoluminescence (PL). The results indicated that the amount of N-substitute-O and N-interstitial defects in these three N-implanted MgO samples showed the same changing tendency as compared with Ms data. Thus, we conclude that the N-substitute-O and N-interstitial defects may play a crucial role in controlling the N+-implanted-induced ferromagnetism. Keywords: N-implanted MgO; orientation-dependent; defect-induced ferromagnetism; microstructure; spintronic
摘要：
Graphene is a unique two-dimensional material, and has unusual properties, including extremely high specific surface area, thermal conductivity, mechanical stiffness, and extraordinary electronic transport properties. More meaningfully, the property of graphene can be modified through elemental doping, surface assembly, plasma etching, and many others. In this paper, flower-like ZnO nanosheets were successfully grown on the O2 plasma treated monolayer graphene using a facile hydrothermal method. The surface morphology and structure, as well as the electrical properties of the samples were investigated. As an application, the photocatalytic property of the as-synthesized ZnO nanosheets was studied. Our report presented here provide an easier and controllable method to synthesize ZnO nanostructures, which have large surface-to-volume ratio and show an improved photocatalytic property due to the synergetic effects of the high specific surface area of the ZnO nanosheets and the fast charge transfer from the ZnO nanosheets to the graphene.
期刊：
Journal of Materials Science: Materials in Electronics,2022年33(30):23834-23840 ISSN：0957-4522
通讯作者：
Haiou Wang<&wdkj&>Dexuan Huo
作者机构：
[Su, Kunpeng; Hu, Xiaojie; Wang, Haiou; Yang, Dexin; Huang, Shuai; Huo, Dexuan; Wang, Yan] Hangzhou Dianzi Univ, Inst Mat Phys, Key Lab Novel Mat Sensor Zhejiang Prov, Hangzhou 310018, Peoples R China.;[Tan, Weishi] Hunan City Univ, Coll Informat & Elect Engn, All Solid State Energy Storage Mat & Devices Key, Yiyang 413002, Peoples R China.;[Liu, Hao] Huaiyin Inst Technol, Fac Appl Technol, Huaian 223003, Peoples R China.;[Liu, Hao; Wang, Haiou; Tan, Weishi] Nanjing Univ Sci & Technol, Dept Appl Phys, Key Lab Soft Chem & Funct Mat, Minist Educ, Nanjing 210094, Peoples R China.
通讯机构：
[Haiou Wang; Dexuan Huo] K;Key Laboratory of Novel Materials for Sensor of Zhejiang Province, Institute of Material Physics, Hangzhou Dianzi University, Hangzhou, China<&wdkj&>Key Laboratory of Soft Chemistry and Functional Materials, Ministry of Education, Department of Applied Physics, Nanjing University of Science and Technology, Nanjing, China<&wdkj&>Key Laboratory of Novel Materials for Sensor of Zhejiang Province, Institute of Material Physics, Hangzhou Dianzi University, Hangzhou, China
摘要：
The transport properties and magnetoresistance (MR) effect of Pr0.7Sr0.3MnO3 (PSMO) film on SrTiO3 (STO) substrate are investigated in this work. The PSMO film is grown on (001) STO substrate by pulsed laser deposition (PLD). The high-resolution X-ray diffraction (XRD) pattern suggests that the Pr0.7Sr0.3MnO3 film shows the out-of-plane single orientation. Atomic force microscopy (AFM) image shows that the surface of the film is smooth. In addition, the significant interference peaks can be found in the XRD. All these confirm the high quality of the PSMO film grown on STO substrate to some extent. The magnetotransport properties and the MR associated to the double exchange (DE) interactions of the Pr0.7Sr0.3MnO3 film have been studied by the resistivity versus temperature and resistivity versus magnetic field data. The temperature dependence of resistivity shows that the film sample undergoes a metal-to-insulator (MI) transition at MI temperature T-MI. The T-MI gradually increases with the increase of applied magnetic field. Under different fields of 1 T, 2 T, 4 T and 6 T, the maximum values of negative MR (MR = [rho-rho(0)/rho(0)] x 100%) reveal about 47.16%, 53.16%, 86.59% and 92.22%, respectively. Compared with other reports on bulk polycrystalline PSMO compounds and polycrystalline PSMO films, the PSMO film on STO in our work has relatively large MR, which is related to the single-oriented growth of PSMO/STO film. The large MR is conducive to the practical applications in magneto-electronic devices. The applied magnetic field dependence of resistivity shows that near T-MI, the resistance changes significantly with the change of the applied field. This also implies that there is a large MR at around T-MI, which can be explained by the traditional DE mechanism.
期刊：
Journal of Applied Physics,2022年131(4):043901 ISSN：0021-8979
通讯作者：
Wang, HO
作者机构：
[Zhang, Hui; Wang, Haiou; Wang, HO; Huo, Dexuan; Wang, Yan] Hangzhou Dianzi Univ, Inst Mat Phys, Key Lab Novel Mat Sensor Zhejiang Prov, Hangzhou 310018, Peoples R China.;[Tan, Weishi] Hunan City Univ, Coll Informat & Elect Engn, All Solid State Energy Storage Mat & Devices Key, Yiyang 413002, Peoples R China.;[Tan, Weishi] Nanjing Univ Sci & Technol, Dept Appl Phys, Key Lab Soft Chem & Funct Mat, Minist Educ, Nanjing 210094, Peoples R China.
通讯机构：
[Wang, HO ] H;Hangzhou Dianzi Univ, Inst Mat Phys, Key Lab Novel Mat Sensor Zhejiang Prov, Hangzhou 310018, Peoples R China.
摘要：
The evolution of the Griffiths phase (GP) with a ferromagnetic metal (FMM) cluster above the Curie temperature (T-C) and its effect on the magnetic properties, electrical transport, magnetoresistance (MR), and magnetocaloric effect (MCE) is studied comprehensively, using bulk compounds of La1-xBaxMnO3 (0.15 <= x <= 0.25) with different lattice distortions but with the same structural symmetry and space group. These La1-xBaxMnO3 samples show ferromagnetic transition at T-C increasing from 229 K for x = 0.15-300 K for x = 0.25, in addition to the presence of GP with FMM clusters in the paramagnetic (PM) region, which have been confirmed by the combination of magnetization (susceptibility) measurements, the GP theory, and electron paramagnetic resonance technology. With increasing the Ba2+ ion doping, GP temperature (T-G) and T-C of La1-xBaxMnO3 are increased, and the GP regime is strengthened. The GP ratio in the PM region reached 27.7% for the sample with x = 0.20. The resistivity decreases and the FMM phase increases with increasing x from 0.15 to 0.25, which can be explained by the decrease in the bandgap (E-g) and the enhancement of the double-exchange effect. Remarkably, large room-temperature MR (similar to 44.7%) can be observed in the sample with x = 0.25 under 60 kOe, which is related to the presence of the GP regime. Furthermore, the MCE is also affected by the GP regime, and it is deduced that the magnetic transition is of second order. The value of magnetic entropy change (|Delta S-M|) reaches 3.04 J/kg K near room temperature for the sample with x = 0.25 under 50 kOe. This value is associated with a relative cooling power (RCP) of 248.1 J/kg. For the sample with x = 0.15, the value of RCP reaches 307.6 J/kg under 50 kOe. The discovery of the MR and MCE near room temperature is of great significance from the practical application of perovskite manganites in magnetic sensors and magnetic refrigerants.
通讯机构：
[Buwen Cao; Renfa Li] C;College of Information and Electronic Engineering, Hunan City University, Yiyang 413000, China<&wdkj&>College of Computer Science and Electronic Engineering, Key Laboratory for Embedded and Cyber-Physical Systems, Hunan University, Changsha 410082, China<&wdkj&>College of Computer Science and Electronic Engineering, Key Laboratory for Embedded and Cyber-Physical Systems, Hunan University, Changsha 410082, China
摘要：
Predicting associations between microRNAs (miRNAs) and diseases from the viewpoint of function modules has become increasingly popular. However, existing methods obtained the relations between diseases and miRNAs only through the construction of similarity networks and neglected the complex network characteristic. In this paper, a new method named combining miRNA function similarities and network topology similarities based on module identification in networks (ComSim-MINE) was developed. Combined similarity is calculated from the harmonic mean between miRNA function similarities and network topology similarities. Experimental results showed that ComSim-MINE can compete with several state-of-the-art weighted function module algorithms, such as ClusterONE, MCODE, NEMO, and SPICi, and achieved the satisfactory results in terms of the composite score of F-measure, sensitivity, and accuracy based on the generated miRNA function interaction network. From the analysis of case studies, some new findings obtained from our proposed method provide clinicians new clues for epidemic diseases, such as COVID-19.
摘要：
The implementation of IoT in industrial management is referred as Industrial IoT (IIoT). It is used to increase the overall operational efficiency. IIoT is considered as the backbone of the contemporary industries. For this purpose, strong security foundations have to be deployed with IIoT. This accelerates the industrial automation process by enrolling thousands of IoT devices and thus befitting the scattered connection and constrained functionalities of the IoT devices. In the Industrial Internet of Things, abnormal traffic detection is an emerging dilemma in network security. It can be ensured by monitoring the traffic flow in large-scale networks. In this connection, the deep learning paradigm has been accepted as the mainstream phenomenon in the field of abnormal traffic detection. It has achieved optimal results due to the constant improvement of computer performance with the help of Artificial Intelligence. Majority of the existing methods are based on supervised learning. As a result, due to numerous constraints, obtaining and marking abnormal traffic data samples in real life is extremely difficult. In addition, due to the diversity and complexity of the abnormal network data, the adaptability of various detection methods is low as well as difficult to judge the new abnormal traffic. Based on the above problems, this paper has proposed a semi-supervised abnormal flow detection framework in the IIoT based network scenario. The proposed model is named Memory Augment Based on Generative Adversarial Network (MeAEG-Net). It detects anomalies by training only normal flow of sample data and comparing the reconstruction errors of the underlying characteristics of input flow of generator module. To improve the generator's training, generative adversarial network has been deployed to tackle the problem of the autoencoder which is susceptible to noise. The generator uses an autoencoder and decoder structure. In addition, the memory augments module is introduced to the autoencoder's sub-network to reduce the generator module's generalization ability and raise the abnormal traffic reconstruction error. Our experimental results show that the method proposed in this paper can achieve a good effect of abnormal traffic detection in IIoT based networks under the premise of learning normal traffic data samples and improving the overall performance in all sectors of the industry.
摘要：
To ensure safe and reliable operation, the ability to ride through various disturbances is vital for a microgrid with multi-inverters. As the voltage and frequency support comes from the power-electronic-based inverters, it is necessary to find a proper control strategy to improve the rejection ability of the DG inverter against disturbances. In this regard, this paper proposes a new distributed secondary frequency control approach for islanded microgrids, in which the main purpose is to remove the frequency deviation under droop control method with better disturbance rejection performance. Unlike many traditional approaches which rely on a detailed control model, the proposed one needs little model information thanks to the model-independent characteristic of active disturbance rejection control (ADRC) technique. A linear extended state observer is introduced to estimate the useless model dynamics (including unknown disturbances, unmodeled dynamics and nonlinear dynamics) which are then compensated in the control input. After the active compensation procedure, the nonlinear frequency control model can be converted into a quasi-linear model, based on which a proportional distributed control algorithm is established to restore the frequency and equalize the active power among the DGs. Simulation results based on a four-inverter-based microgrid show that the proposed approach achieves frequency restoration, active power sharing, as well as satisfactory disturbance rejection performance.
摘要：
An electric pulse-controlled thermal spin injector is theoretically proposed, which consists of a junction with a single-molecule magnet sandwiched between the ferromagnetic and nonmagnetic leads. By applying a temperature gradient and a time-varying bias pulses across the junction, the spin direction of the single-molecule magnet can be controlled to be antiparallel or parallel to the magnetization of the ferromagnetic lead by a spin-transfer torque effect, and the spin polarization of thermoelectric current tunneling through this junction can be switched from +100% to −100% corresponding to a molecule’s spin orientation, respectively. Our numerical results show that the spin polarization of the thermoelectric current will not be easily affected by the magnetization of electrodes, which can be fully and precisely tuned in electric manner. This device scheme can be compatible with current technologies and has potential applications in future spin caloritronics devices.
