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Cheating Detectable Secret Sharing Scheme from Multiplicative Homomorphic Authentication Function
Get PDFCheating Detectable Secret Sharing (CDSS for short) is a secret sharing scheme that adds the property of detecting the presence of cheaters submitting invalid shares when reconstructing a secret. A major topic of research in CDSS has been the attempt to improve efficiency with suitable authentication functions. In this paper, we construct CDSS based on an authentication function with multiplicative homomorphism, which has not been employed so far. It possesses some interesting properties and possesses the advantage that security can be proven simply by showing possession of such properties. Furthermore, we construct a secure CDSS with multiplicative homomorphic under some parameter constraints and show that this scheme is sufficient for practical use. The scheme achieves a bit length that is one bit longer than the theoretical lower bound
EFFECT OF IMPURITIES ON THE EMISSIVITY OF CARBON NANOTUBES GROWN BY FLOATING-CATALYST CHEMICAL VAPOR DEPOSITION METHOD
Get PDFWe have investigated the effect of the impurity, which mainly consists of fine particles of carbon and iron, on the emissivity and crystallinity of carbon nanotubes (CNTs) grown by floating-catalyst chemical vapor deposition (FCCVD) and the effect of post-growth cooling rate on the impurity concentration. The amount of carbon particles significantly depends on the cooling rate. The emissivity of the slightly contaminated CNTs, which contains a small amount of carbon particles, tends to be greater than that of the pure CNTs
ANALYSIS OF PERIODIC ORBITS IN PERMUTATION BINARY NEURAL NETWORKS
Get PDFThis paper studies permutation binary neural networks characterized by local binary connection, global permutation connection and the signum activation function. The networks are simple in structure, are easy to - implement, and can generate various binary periodic orbits. In order to analyze the dynamics, we define two feature quantities that evaluate complexity and stability of the periodic orbits. Using the feature quantities, we have analyzed the 6-dimensional networks. Typical periodic orbits are confirmed experimentally
A STUDY ON TOPOLOGY OPTIMIZATION OF IPMSM WITH TIME DOMAIN CHARACTERISTIC USING COMBINATION USE OF ELECTROMAGNETIC FIELD ANALYSIS STRONGLY COUPLED WITH THREE-PHASE AC CIRCUIT AND MATHEMATICAL PROGRAMMING
Get PDFSince the interior permanent magnet synchronous motor (IPMSM) is essential for the driving of the hybrid-car and electric vehicle, the design of highly efficient IPMSM is enthusiastically requested by the industrial world from the viewpoint of the carbon neutrality. Because many design parameters are included in designing IPMSM, it is difficult to automatically determine all parameters. Regarding the determination of motor structure, the optimization techniques are indispensable. The topology optimization has the affinity for the deriving the novel structure of IPMSM because the topology of IPMSM is directly set to the design parameter. Although the sensitivity analysis based on the adjoint variable method is frequently applied to the topology optimization of IPMSM to reduce the elapsed time in the magnetostatic field, the sensitivity calculation in nonlinear time domain has not been applied to the transient analysis of IPMSM from the viewpoint of the difficult implementation caused by the rotor rotation and change of electromagnetic field in time domain. In this paper, to consider the accurate effect of three-phase AC circuit to the electromagnetic field characteristics in the steady-state of IPMSM, the time domain adjoint variable method with the magnetic nonlinearity is proposed. Furthermore, its method is applied to the topology optimization of IPMSM to enhance the motor output under the condition that the input power is kept less than the specified value defined in the reference model of IPMSM
STUDY OF A QUARTER-WAVE METALLIC PLATE COMPOSED OF PERIODIC CROSSED SLOTS WITH DIELECTRIC SUBSTRATES
Get PDFA metallic quarter-wave plate composed of periodic crossed slots with the same arm length on dielectric substrates is analyzed using the finite-difference time-domain method with the periodic boundary condition. High transmittance is obtained regardless of a hole shape by adding a thin dielectric layer on the top of the metal film, even when the metal film is loaded on a substrate. The adjustment of a required phase difference of 90° can be achieved by proper choice of the periodic lengths in the x and y directions. It is found that polarization conversion from a linearly to a circularly polarized wave can be realized over a wide range of wavelengths
Proposal of a 2 Step SAR-TDC using Delta Sigma Method
Get PDFIn this paper, we propose a 2-step Successive Approximation Register Time-to-Digital Converter (SAR-TDC) using a Vernia type delta sigma TDC (VDSTDC). The system is equipped with a SAR-TDC and Vernier type Digital-to Time Converter (VDTC) with second-order noise shaping by a feed-forward type delta sigma structure. It can improve the time resolution and reduce the quantize error with wide full scale. The effectiveness of the proposed system is verified by MATLAB/Simulink
A PROPOSAL FOR A CONTROL METHOD IN THE TASK OF COLLECTING UNKNOWN SHAPED OBJECTS : REDUCING THE AMOUNT OF CONTROL USING SOFT MANIPULATORS
Get PDFRecently, there is a growing demand for robot arms that can perform tasks such as sorting vegetables and retrieving fuel debris at nuclear power plants. Many robot arms require a large amount of control and computation to sense the object to be grasped. In our previous research, we developed a soft manipulator that mimics the grasping strategy of an octopus. This soft manipulator can grasp without sensing the object due to the flexibility of the arm. In this study, we apply this soft manipulator to propose an autonomous collection system for objects of unknown shape, which reduces the amount of computation required for object sensing and manipulator control
A MODIFIED CIRCULARLY SYMMETRIC PHOTONIC BANDGAP ANTENNA
Get PDFA circularly symmetric photonic-bandgap antenna is proposed and analyzed using the body-of-revolution finite-difference time-domain method. The frequency characteristics are investigated when the resonance condition of the defect region is slightly shifted. It is found that a gain of 25.8 dBi is obtained with an aperture efficiency of 57.7 %
ANALYSIS OF ENERGY TRANSITION OF AL ATOM IN SUPERFLUID HELIUM BUBBLE USING MORECULAR ORBITAL CALCULATION
Get PDFWe have been studying the electron transition of an atom in superfluid helium bubble from the experimental and quantum numerical calculation point of view. In the recent experiment of Al spectrum in the bubble, the spectrum was quite well observed. We have also started to analyze this spectrum from the electron energy levels obtained from the quantum numerical calculations. The quantum states are, of course, affected by surrounded superfluid helium. Concerning the total bubble energy, we use not only the atom energy, but the surface and volume energies. We have investigated the absorption and emission process. In particular, we focus on the electron energy levels in the bubble. The simple model is adopted that the superfluid helium bubble is replaced by Al is placed in the center and surrounded He atoms, which is estimated from the density, and the radial distribution function. We have assumed the bubble shape spheroid in the ground state, and that spherical in the excited state. Although there is a quantitative difference from the numerical calculation, the qualitative properties in emission absorption process of Al spectrum in the bubble was successfully reproduced
A STUDY ON SPECIFIC PERSON DETECTION METHOD FOR TSUKUBA CHALLENGE USING YOLO ALGORITHM
Get PDFIn this paper, we describe the development of an omnidirectional camera based specified person searching algorithm which is for one of the Tsukuba Challenge tasks. The employment of an omnidirectional camera enables wide viewing angles without dead angles compared with conventional cameras. YOLOv5 uses images from an omnidirectional camera to identify people. The propose algorithm was implemented as ROS-based application that enables rapid verification as well as rapid prototyping. The validity of the propose algorithm is confirmed by preliminary experiments that simulated Tsukuba Challenge environments