A Rational Threshold Signature Model and Protocol Based on Different Permissions

This paper develops a novel model and protocol used in some specific scenarios, in which the participants of multiple groups with different permissions can finish the signature together. We apply the secret sharing scheme based on difference equation to the private key distribution phase and secret reconstruction phrase of our threshold signature scheme. In addition, our scheme can achieve the signature success because of the punishment strategy of the repeated rational secret sharing. Besides, the bit commitment and verification method used to detect players' cheating behavior acts as a contributing factor to prevent the internal fraud. Using bit commitments, verifiable parameters, and time sequences, this paper constructs a dynamic game model, which has the features of threshold signature management with different permissions, cheat proof, and forward security.Mathematics, AppliedSCI(E)[email protected]

Solar Image Restoration with the CycleGAN Based on Multi-fractal Properties of Texture Features

Texture is one of the most obvious characteristics in solar images and it is normally described by texture features. Because textures from solar images of the same wavelength are similar, we assume that texture features of solar images are multi-fractals. Based on this assumption, we propose a pure data-based image restoration method: with several high-resolution solar images as references, we use the Cycle-Consistent Adversarial Network to restore blurred images of the same steady physical process, in the same wavelength obtained by the same telescope. We test our method with simulated and real observation data and find that our method can improve the spatial resolution of solar images, without loss of any frames. Because our method does not need a paired training set or additional instruments, it can be used as a post-processing method for solar images obtained by either seeing-limited telescopes or telescopes with ground-layer adaptive optic systems

Regulation of placenta growth factor expression in retinal cells

Purpose:We have previously reported the expression of placenta growth factor in proliferative diabetic retinopathy (PDR). The aim of this study was to identify factors which regulate the expression of PlGF by retinal cells in vitro. Methods:Confluent culture of bovine retinal microvascular endothelial cells, bovine pericytes and human RPE cells were exposed to 10ng/ml VEGF, 100ng/ml VEGF, 5mM glucose, 15mM glucose and 25mM glucose and incubated for 24 hours at 37oC. Total RNA was isolated, reverse transcription and polymerse chain reaction (RT-PCR) were performed. For detection of PlGF protein, the confluent cells were incubated under the above conditions for 24 hours in serum-free culture media. The media were collected and western blotting for PlGF was performed following immunoprecipition. Results:Endothelial cells consistently expressed PlGF at both the gene and protein level in culture medium without additions. 100ng/ml VEGF and 15mM glucose both up-regulated expression. Pericytes expression of PlGF was very low level and did not appear to be affected by either VEGF or glucose. There was no expression of PlGF mRNA or protein in human RPE under the experimental conditions employed. To elucidate the mechanism for glucose and VEGF up-regulation of PlGF expression in endothelial cells, VEGFR-1 and VEGFR-2 were blocked using neutralizing antibodies immediately prior to addition of 100ng/ml and 15mM glucose. VEGF and glucose stimulation was diminished after blocking the VEGFR-2 but not VEGFR-1. Conclusion:Changes in VEGF and glucose levels during the progression of PDR may explain the up-regulation of PlGF during active pre-retinal neovascularization. The affect appears to be regulated via VEGFR-2

PSF–NET: A Nonparametric Point-spread Function Model for Ground-based Optical Telescopes

Ground-based optical telescopes are seriously affected by atmospheric turbulence induced aberrations. Understanding properties of these aberrations is important both for instrument design and image restoration method development. Because the point-spread function can reflect performance of the whole optic system, it is appropriate to use the point-spread function to describe atmospheric turbulence induced aberrations. Assuming point-spread functions induced by the atmospheric turbulence with the same profile belong to the same manifold space, we propose a nonparametric point-spread function—PSF–NET. The PSF–NET has a cycle convolutional neural network structure and is a statistical representation of the manifold space of PSFs induced by the atmospheric turbulence with the same profile. Testing the PSF–NET with simulated and real observation data, we find that a well trained PSF–NET can restore any short exposure images blurred by atmospheric turbulence with the same profile. Besides, we further use the impulse response of the PSF–NET, which can be viewed as the statistical mean PSF, to analyze interpretation properties of the PSF–NET. We find that variations of statistical mean PSFs are caused by variations of the atmospheric turbulence profile: as the difference of the atmospheric turbulence profile increases, the difference between statistical mean PSFs also increases. The PSF–NET proposed in this paper provides a new way to analyze atmospheric turbulence induced aberrations, which would benefit the development of new observation methods for ground-based optical telescopes

Short-term Runoff Forecasting based on Hydrological Factors at Nanchang Section of Ganjiang River, China

With the change of global climate and underlying surface characteristics, and increasing human activities, hydro-meteorological factors such as precipitation, evaporation, and runoff. Etc., are directly affected, therefore the assumption of stationarity may no longer exist. In a changing environment, the conventional runoff forecasting methods become invalid, which brings challenges to accurate hydrometeorological forecast. A hydrological model based on the changing environment was employed to forecast the runoff at Nanchang Section of Ganjiang River in this paper, and the rationality and validity of the built model were verified. The results shows that the built hydrological model has high accuracy in the short-term runoff forecasting, and better forecasting effect has been obtained after the parameters calibration and the real-time correction of the predicted runoffs, which can provide the strong support for the scientific water resources operation decision and also provide the boundary conditions of water level and water quality for the hydrodynamic and water-quality simulation at the Nanchang Section of the Ganjiang River

Review and prospect about water resources operation research

The concept of water resources operation is expatiated and classified and the theories and methods with regard to water resources operation are also summarized. Research progress of water resources operation exists to analyse the problems and to take a look to the future of research directions in the field of water resources operation. In conclusion, the research on water resources operation needs a combination with the actual state of projects, climate change and increasing human activities, actually considering water resources demands and employing uniform control of water quantity and quality, which could ensure the sustainable utilization of water resources in China

Review and prospect about water resources operation research

The concept of water resources operation is expatiated and classified and the theories and methods with regard to water resources operation are also summarized. Research progress of water resources operation exists to analyse the problems and to take a look to the future of research directions in the field of water resources operation. In conclusion, the research on water resources operation needs a combination with the actual state of projects, climate change and increasing human activities, actually considering water resources demands and employing uniform control of water quantity and quality, which could ensure the sustainable utilization of water resources in China

Regional Flood Risk Management Modeling and Application

China is one of the countries with frequent flood disaster, and it does fall often with more precipitation especially from June to October in the Yangtze River, which would very easily cause floods thereby seriously threating to the safety of each region along the Yangtze River. How to manage regional flood risk reasonably and efficiently under the new situation of the joint effects of climatic change and human activities deserves more researches. The regional flood risk management model is built and applied in the Jingjiang section of the Yangtze River to derive regional flood processes under the condition of floodwall break and assess the effects of flood on each factor in the region. The built model is reliable and practical with reasonable results, would support some sort of technical help for regional flood risk management, water resources protection and measure-making of flood prevention and disaster mitigation