According to the DNA encryption algorithm and the double-chaotic system which contains the optical chaos and the coupled map lattice chaotic system, a novel image encryption-then-transmission system is proposed. In the system, with identical chaotic injection from a master laser with two optical feedbacks, two slave lasers (SL1 and SL2) can output similar chaotic signals served as chaotic carrier to transmit image and used to generate the core part of the encryption scheme. A 128-b key is selected to generate the original value of the double-chaotic system, which decides the DNA complementary rule, hence, the key is hypersensitive in encryption and decryption process. The security analysis demonstrates the effectiveness of the proposed encryption system. The simulation results verify that the cryptosystem is enough against the traditional attacks, such as statistical attack, differential attack, brute force attack, and entropy attack. Moreover, the encrypted image can be the optical message and transmitted in 10 km single-mode fiber channel from SL1 to SL2. In order to ensure the security, we use the chaos masking technique to modulate and demodulate the optical message. Through numerical simulations of the cross-correlation function, the chaos synchronization between SL1 and SL2 is desired. The Q-factor is 9.559 and the bit error rate is 5.771 × 10 −22 .

Cloud servers are very suitable for sharing and storing image data and meanwhile it is confronted with many security and privacy problems. Optical chaos and hardware implementation of image encryption possess distinct superiorities in secret image sharing. Hence, combining the advantages of advanced reduced instruction set computer machine (ARM)-embedded platform Exynos4412 model, together with vertical-cavity surface emitting laser (VCSEL) subject to positive optoelectronic feedback (POEF), a novel color image encryption and transmission system is experimentally realized and appraised. We investigate the dynamic behaviors of the VCSEL and obtain the chaotic output. An analog to digital conversion (ADC) module is utilized for optical chaos data acquisition. The improved gravity model and the double sine map are exploited to encrypt the image, and the encrypted image is securely shared by cloud services. The user can download the encrypted image and decrypt it by the hardware board. The experiment results reveal that the system has an excellent resistance to common attacks. Compared to the numerical simulation, our hardware implementation for such a color image encryption and transmission system is formidable to actualize, but we successfully implemented and tested in a real-world environment. By comparing experimental and simulation results, the consistent results are found. Therefore, in the case of similar encryption effect, the user's information privacy protection in the actual industrial or commercial systems can be securely guaranteed on our hardware platform.

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Optical networks-on-chips (ONoCs) is an effective and extensible on-chip communication technology, which has the characteristics of high bandwidth, low consumption, and low delay. In the design process of ONoCs, power loss is an important factor for limiting the scalability of ONoCs. Additionally, the optical signal-to-noise ratio (OSNR) is an index to measure the quality of ONoCs. Nowadays, the routing algorithm commonly used in ONoCs is the dimension-order routing algorithm, but the routing paths selected by the algorithm have high power loss and crosstalk noise. In this paper, we propose a 5×5 all-pass optical router model for two-dimensional (2-D) mesh-based ONoCs. Based on the general optical router model and the calculation models of power loss and crosstalk noise, a novel algorithm is proposed in ordder to select the routing paths with the minimum power loss. At the same time, it can ensure that the routing paths have the approximately optimal OSNR. Finally, we employ the Cygnus optical router to verify the proposed routing algorithm. The results show that the algorithm can effectively reduce the power loss and improve the OSNR in the case of network sizes of 5×5 and 6×6. With the increase of the optical network scale, the algorithm can perform better in reducing the power loss and raising the OSNR.

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Water diffusion and dynamic motion within the confined sPEEK channel are examined. To produce materials with different channel dimension, sPEEK/hyper branch mBMI membrane are prepared by insitu polymerization. NMR T 1 and T 2 relaxation time measurements are employed to understand the dynamic behavior of water at low ( =2-3) medium ( =4-8) and high ( =14-20) water uptake in these membranes. At fully saturated extreme, the activation energy is found to be higher (30 to 40 kJ/mole) than that of the bulk water (20 to 30 kJ/mole). This is due to the fact that water diffusion occurs in the constraint channel, thus experiencing higher viscosity. On the other hand, at low water uptake, the water migration activation energy is lower than that of the bulk or in the fully saturated sample. This suggests the proton motion involves the relay motion of interconnected hydrogen boding network formed between the sulfonated/ amine group of mBMI with the residue water.

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