1,727 research outputs found
ANALYSIS OF THE RELIEVING EFFECT OF THE INNOVATION OF IDEOLOGICAL AND POLITICAL EDUCATION TEACHING MODE IN COLLEGES AND UNIVERSITIES ON THE ANXIETY OF COLLEGE STUDENTS FROM THE PERSPECTIVE OF EDUCATIONAL PSYCHOLOGY
ANALYSIS OF THE RELIEVING EFFECT OF THE INNOVATION OF IDEOLOGICAL AND POLITICAL EDUCATION TEACHING MODE IN COLLEGES AND UNIVERSITIES ON THE ANXIETY OF COLLEGE STUDENTS FROM THE PERSPECTIVE OF EDUCATIONAL PSYCHOLOGY
Unifying ultrafast demagnetization and intrinsic Gilbert damping in Co/Ni bilayers with electronic relaxation near the Fermi surface
The ability to controllably manipulate the laser-induced ultrafast magnetic
dynamics is a prerequisite for future high speed spintronic devices. The
optimization of devices requires the controllability of the ultrafast
demagnetization time, , and intrinsic Gilbert damping, . In previous attempts
to establish the relationship between and , the rare-earth doping of a
permalloy film with two different demagnetization mechanism is not a suitable
candidate. Here, we choose Co/Ni bilayers to investigate the relations between
and by means of time-resolved magneto-optical Kerr effect (TRMOKE) via
adjusting the thickness of the Ni layers, and obtain an approximately
proportional relation between these two parameters. The remarkable agreement
between TRMOKE experiment and the prediction of breathing Fermi-surface model
confirms that a large Elliott-Yafet spin-mixing parameter is relevant to the
strong spin-orbital coupling at the Co/Ni interface. More importantly, a
proportional relation between and in such metallic films or heterostructures
with electronic relaxation near Fermi surface suggests the local spin-flip
scattering domains the mechanism of ultrafast demagnetization, otherwise the
spin-current mechanism domains. It is an effective method to distinguish the
dominant contributions to ultrafast magnetic quenching in metallic
heterostructures by investigating both the ultrafast demagnetization time and
Gilbert damping simultaneously. Our work can open a novel avenue to manipulate
the magnitude and efficiency of Terahertz emission in metallic heterostructures
such as the perpendicular magnetic anisotropic Ta/Pt/Co/Ni/Pt/Ta multilayers,
and then it has an immediate implication of the design of high frequency
spintronic devices
REGULATION OF ADHERENS JUNCTION AND MECHANICAL FORCE DURING APOPTOSIS IN EPITHELIAL TISSUE MORPHOGENESIS
Ph.DDOCTOR OF PHILOSOPH
Learning large margin multiple granularity features with an improved siamese network for person re-identification
Person re-identification (Re-ID) is a non-overlapping multi-camera retrieval task to match different images of the same person, and it has become a hot research topic in many fields, such as surveillance security, criminal investigation, and video analysis. As one kind of important architecture for person re-identification, Siamese networks usually adopt standard softmax loss function, and they can only obtain the global features of person images, ignoring the local features and the large margin for classification. In this paper, we design a novel symmetric Siamese network model named Siamese Multiple Granularity Network (SMGN), which can jointly learn the large margin multiple granularity features and similarity metrics for person re-identification. Firstly, two branches for global and local feature extraction are designed in the backbone of the proposed SMGN model, and the extracted features are concatenated together as multiple granularity features of person images. Then, to enhance their discriminating ability, the multiple channel weighted fusion (MCWF) loss function is constructed for the SMGN model, which includes the verification loss and identification loss of the training image pair. Extensive comparative experiments on four benchmark datasets (CUHK01, CUHK03, Market-1501 and DukeMTMC-reID) show the effectiveness of our proposed method and its performance outperforms many state-of-the-art methods
First-principles study on the effective masses of zinc-blend-derived Cu_2Zn-IV-VI_4 (IV = Sn, Ge, Si and VI = S, Se)
The electron and hole effective masses of kesterite (KS) and stannite (ST)
structured Cu_2Zn-IV-VI_4 (IV = Sn, Ge, Si and VI = S, Se) semiconductors are
systematically studied using first-principles calculations. We find that the
electron effective masses are almost isotropic, while strong anisotropy is
observed for the hole effective mass. The electron effective masses are
typically much smaller than the hole effective masses for all studied
compounds. The ordering of the topmost three valence bands and the
corresponding hole effective masses of the KS and ST structures are different
due to the different sign of the crystal-field splitting. The electron and hole
effective masses of Se-based compounds are significantly smaller compared to
the corresponding S-based compounds. They also decrease as the atomic number of
the group IV elements (Si, Ge, Sn) increases, but the decrease is less notable
than that caused by the substitution of S by Se.Comment: 14 pages, 6 figures, 2 table
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