1,829 research outputs found
"Give Me This and I am Yours": Masks & Identity in Louisa May Alcott\u27s A Modern Mephistopheles
Direct Calculation of Thermodynamic Quantities for Heisenberg Model
The XXX Heisenberg model is studied at finite temperature. The free energy is
derived without recourse to Thermal Bethe Ansatz method and Quantum Transfer
Matrix method. The result perfectly agrees with the free energy derived by
Thermal Bethe Ansatz method. An explicit expression of the cluster expansion
coefficient in arbitrary order is presented for the first time.Comment: 26 page
Deciphering the Drivers of Smart Livestock Technology Adoption in Japan: A Scoping Review, Expert Interviews, and Grounded Theory Approach
With global demand for animal products projected to increase significantly by
2050, understanding the factors that influence the adoption of smart livestock
technologies has become increasingly crucial. Conducted within the unique
agricultural context of Japan, our study builds upon traditional theoretical
frameworks that often oversimplify farmers' decision-making processes. By
employing a scoping review, expert interviews, and a Modified Grounded Theory
Approach, our research uncovers the intricate interplay between individual
farmer values, farm management policies, social relations, agricultural
policies, and livestock industry trends. We particularly highlight the unique
dynamics within family-owned businesses, noting the tension between an
"advanced management mindset" and "conservatism." Our study underscores
technology adoption's sequential and iterative nature, intricately tied to
technology availability, farmers' digital literacy, technology implementation
support, and observable technology impacts on animal health and productivity.
Despite certain limitations, our findings carry profound implications for
stakeholders, providing valuable insights to overcome adoption barriers and
advocating for more sustainable, efficient, and animal welfare-oriented
livestock production systems. This research establishes a solid foundation for
future explorations into smart livestock technology adoption.Comment: 56 pages, 3 figure
Mass and generalized Thiele equation of the magnetic skyrmion
An analytical expression is obtained to the mass of an isolated magnetic
skyrmion and its linearized equation of motion. The magnetic skyrmion is viewed
as a topologically protected spin-wave soliton in the magnetic ultrathin films
stabilized by the interfacial-Dzyaloshinskii-Moriya interaction. The equations
of motion are derived from the Landau-Lifshitz-Gilbert equation for both the
skyrmion charge and magnetization centers. They are generalized Thiele
equations, including gyro-term, dissipation term, external force, an
acceleration term with the tensorial mass, and time derivatives of the external
forces. The equation of motion of the center of the skyrmion charge essentially
shows the massless nature of the skyrmion. In contrast, the equation of motion
for the magnetization center results in a finite mass that is in the same order
as the Doring mass density for the linear domain wall. Furthermore, the time
derivative of the external force predominantly contributes to the immediate
response of the skyrmion motion, i.e., the mass-less property remains even
after the skyrmion acquires its kinetic mass.
A micromagnetic simulation based on the LLG equation was performed for
various magnetic parameters. Obtained trajectories at 0 K are compared with the
theoretical predictions.Comment: 28 pages, 3 figure
Robust Model Selection for Classification of Microarrays
Recently, microarray-based cancer diagnosis systems have been increasingly investigated. However, cost reduction and reliability assurance of such diagnosis systems are still remaing problems in real clinical scenes. To reduce the cost, we need a supervised classifier involving the smallest number of genes, as long as the classifier is sufficiently reliable. To achieve a reliable classifier, we should assess candidate classifiers and select the best one. In the selection process of the best classifier, however, the assessment criterion must involve large variance because of limited number of samples and non-negligible observation noise. Therefore, even if a classifier with a very small number of genes exhibited the smallest leave-one-out cross-validation (LOO) error rate, it would not necessarily be reliable because classifiers based on a small number of genes tend to show large variance. We propose a robust model selection criterion, the min-max criterion, based on a resampling bootstrap simulation to assess the variance of estimation of classification error rates. We applied our assessment framework to four published real gene expression datasets and one synthetic dataset. We found that a state-of-the-art procedure, weighted voting classifiers with LOO criterion, had a non-negligible risk of selecting extremely poor classifiers and, on the other hand, that the new min-max criterion could eliminate that risk. These finding suggests that our criterion presents a safer procedure to design a practical cancer diagnosis system
Manipulating 1-dimensinal skyrmion motion by external magnetic field gradient
We have investigated an analytic formula of the 1-dimensional magnetic
skyrmion dynamics under external magnetic field gradient. We find excellent
agreement between the analytical model and micromagnetic simulation results for
various magnetic parameters such as the magnetic field gradient, Gilbert
damping constant. We also observe much faster velocity of the chiral domain
wall (DW) motion. The chiral DW is exist with smaller interfacial
Dzyaloshinskii-Moriya interaction energy density cases. These results provide
to develop efficient control of skyrmion for spintronic devices.Comment: 15 pages, 5 figures, 1 tabl
A direct calculation of the free energy from the Bethe ansatz equation for the Heisenberg model
Thermodynamics of the XXX Heisenberg model is studied. The trace of the
Boltzmann weight with respect to the Hilbert space is taken in the
thermodynamic limit with the number of up-spins being fixed. The expression of
the trace gives an explanation why the correct thermodynamic quantities are
derived from the string hypothesis. Combining this with the previous result, we
conclude that the free energy can be calculated only by assuming the Bethe
ansatz equation. The method is more direct than other known methods which were
used to derive the free energy.Comment: 52 pages, submitted to J. Math. Phy
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