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In this paper, we demonstrate a physical experiment of optical scanning holography based on random-phase encoding and connected component labeling. Usually, a pinhole is used as one of pupil functions in conventional optical scanning holography experiment. Although such a structure is relatively simple, defocus noise trends to appear as a blur in sectional image reconstruction. In our experiments, a random-phase pupil is used, and it can easily transform defocus noise into speckle-like patterns with the increase in defocus distance. We apply connected component labeling to deal with the speckles, and the focus image can be recovered clearly from reconstructed images.

In this paper, we declare that the scattering system of coherence light passing through a thin-layer highly scattering medium can be treated as a 4f system of single random phase encoding (SRPE). Assuming no energy loss, the target image behind a thin-layer highly scattering medium can be recovered by using an attack method in a SRPE-4f encryption system. The idea originates from the analysis of speckle field and theoretical model of the system. On the one hand, the statistical distribution of the speckle in the scattering system is consistent with that of the cyphertext in the corresponding SRPE-4f encryption system, which provides the base for equivalent replacement. On the other hand, the point spread function of a thin-layer highly scattering medium is equivalent to the Fourier transform of random phase mask of the SRPE-4f system, which can be used for key estimation in scattering imaging. Both the theory analysis and results of the experiment verify the validity and feasibility of our proposed, and we believe this contribution will open up a novel way to deepen the research of imaging through scattering medium.

This study establishes a two-echelon supply chain with one manufacturer who invests in energy-saving products (ESPs) and one retailer who sells the products and may possess demand-forecast advantage. Considering government subsidy and consumer preference for ESPs and a random demand, we develop a four-stage Stackelberg game model to research the optimal strategies of the information investment and sharing of the retailer and the energy-saving R&D of the manufacturer. The results show the following: (1) When incurring a low information investment cost, the retailer is willing to invest in information acquisition techniques, while the retailer agreeing to share market information is related to the government subsidies and the probability of a high demand. The optimal strategy for the retailer is to share information when the probability of a high demand is less than 50% and the government subsidies for ESPs are high. Otherwise, the optimal strategy is not to share information. (2) The manufacturer not always expects the retailer to share information, which depends on the probability of a high demand and manufacturing cost. Especially, when the probability of a high demand is less than 50%, only a manufacturer incurring high cost will expect. (3) If the retailer refuses to share the information, the manufacturer can motivate the retailer to change his/her decision by sharing the information investment cost.

This document proposes a novel joint relaying and jamming method based on the concept of spectrum sensing for secure relay networks. The opportunistic operating frequency point is determined according to the physical characteristics of wireless channels. The proposed method captures ‘two birds’: anti-eavesdrop and anti-interference.

In this paper, a block reconstruction method of object image based on compressed sensing(CS) and orthogonal modulation is presented. Using this method, the amount of data processing can be greatly reduced due to the application of CS theory and it brings convenience for post-processing. The method can be utilized especially when we just need to reconstruct partial of a huge image, because the orthogonal basis matrix can extract the measurements of corresponding block, and then the needed partial image can be reconstructed directly instead of reconstructing the whole huge image at first. Therefore, this method can reduce the redundant computation in process of reconstruction. And the total amount of calculation is also greatly reduced. The feasibility is verified by results of an experiment, in which we use a video projector to incorporate the random measurement matrix into the system.

The use of graph theory to improve the secrecy performance of a wireless multi-hop relaying system is investigated. Particularly, we consider a wireless wiretap network with multi-relay and multi-eavesdropper. A secrecy graph is first established according to the network topology. After building the weight of each edge, an efficient max-min path selection (MM-PS) criterion is then proposed to select an appropriate path for relaying based on shortest path algorithm. Simulation results verified the effectiveness and efficiency of the proposed MM-PS criterion and show that cooperative relaying can bring considerable performance improvement.

Traffic-related air pollution is known to be associated with skin aging manifestations. We previously found that the use of fossil fuels was associated with skin aging, but no direct link between indoor air pollutants and skin aging manifestations has ever been shown. Here we directly measured the indoor PM2.5 exposure in 30 households in Taizhou, China. Based on the directly measured PM2.5 exposure and questionnaire data of indoor pollution sources, we built a regression model to predict the PM2.5 exposure in larger datasets including an initial examination group (N = 874) and a second examination group (N = 1003). We then estimated the association between the PM2.5 exposure and skin aging manifestations by linear regression. In the initial examination group, we showed that the indoor PM2.5 exposure levels were positively associated with skin aging manifestation, including score of pigment spots on forehead (12.5% more spots per increase of IQR, P-value 0.0371), and wrinkle on upper lip (7.7% more wrinkle on upper lip per increase of IQR, P-value 0.0218). The results were replicated in the second examination group as well as in the pooled dataset. Our study provided evidence that the indoor PM2.5 exposure is associated with skin aging manifestation in a Chinese population.