Aiming at the problems of large area and large consumption of fresh randomness in Threshold Implementation （TI） of SM4， an improved threshold implementation scheme of SM4 was proposed. In the case of satisfying the threshold implementation theory， the operation of S-box nonlinear inversion was shared with no fresh randomness， and a domain-oriented multiplication mask scheme was introduced to reduce the fresh randomness consumption of S-box to 12 bits. Based on the idea of the pipeline， a new SM4 serial architecture with 8-bit data width was designed. The threshold implementation of S-box was reused， and the linear function of SM4 was optimized to make the area of threshold implementation of SM4 more compact， only 6 513 GE. In comparison with the TI scheme of SM4 with 128-bit data width， the area of the proposed scheme is reduced by more than 63.7%， and there is a better trade-off between speed and area. The side-channel experimental results show that the proposed scheme has the capability of anti-first-order Differential Power Analysis （DPA）.

To solve the problems of large energy consumption and scarcity of spectrum resources in the traditional Internet of Things （IoT）， a Multiple Input Multiple Output-Ambient Backscatter Communication （MIMO-AmBC） system model which is constructed by an ambient backscatter， a Cooperative Receiver （CRx） and ambient Radio Frequency （RF） source was proposed. First， the system model was analyzed by using the Parasitic Symbiotic Radio （PSR） scheme to derive the Signal-to-Noise Ratio （SNR）. Secondly， the approximate expressions for the ergodic rates of the primary link and the backscatter link were derived， and the maximum expression for the ergodic rate of the backscatter link was obtained. Finally， the proposed system model was compared with the traditional cellular network and Commensal Symbiotic Radio （CSR） scheme. The experimental results verify the correctness of the theoretical derivation and give some meaningful conclusions：1） the backscatter link rate increases with the logarithm of the number of receiving antennas and has nothing to do with the number of transmitting antennas； 2） when the SNR is 10 dB， the sum rate of the PSR scheme is higher than those of the traditional scheme and the CSR scheme by 36.8% and 29.9% respectively. Although the primary link rate of the PSR scheme is 5.5% lower than that of the CSR scheme， the ergodic rate of the backscatter link is 7.7 times higher than that of the CSR scheme， which provides theoretical reference for choosing the AmBC symbiosis scheme for practical applications.

As the fabric defect type of diversity and traditional artificial detection methods inefficient ,in order to detect the fabric defect more effective, A new approach, SGE, based on saliency region feature for fabric defect detection is studied. In this approach, the original image is divided into two parts, one extracts the saliency region feature of fabric defect by improved FSR roughly, another employing the gabor filter and taking the amplitude as an output characteristics, and extracts the saliency region feature of fabric defect by PSR accurately, then by using maximum entropy to segment the saliency region respectively and fused the sub-images. The result is get got by calculating perimeter and area of the contours to removal the isolated points. The experiment selects four types of typical fabric defect images and OpenCV library is used. The experiment result shows that the algorithm, without prior learning，meet the real-time.

In the existing methods of periodic B-spline interpolation, coefficients of B-spline basis functions are determined by iterative algorithms. To overcome the weakness of the existing methods, new parallel algorithm for computing coefficients of B-spline basis functions were established. First, this paper established orthogonal B-spline basis and derived parallel algorithm for coefficients of orthogonal B-spline basis functions; and then derived parallel algorithm for coefficients of B-spline basis functions by using the relation between coefficients of orthogonal B-spline basis functions and coefficients of B-spline basis functions; at last this paper derived explicit formulas for both coefficients of B-spline basis functions and value of interpolated point with the 2nd, the 3rd and the 4th order periodic interpolating B-spline functions. The presented method retains the simplicity of B-spline basis functions while realizing fast parallel algorithm for coefficients of B-spline basis functions.