A Novel Image Encryption Method Based On Couple Mapped Lattice and Two-Stage Diffusion

Yunsheng Zhong,Xu Xu 보안공학연구지원센터 2015 International Journal of Security and Its Applicat Vol.9 No.11

In this paper, a novel image encryption method which is based on the coupled map lattice (CML) and two-stage diffusion is proposed. The author employs the two-stage diffusion to process images. The plain image is expanded into two composed of selected four bit-planes and diffuse them at bit-level as first stage diffusion, then reconstruct them as the input of block diffusion, which is served as second stage diffusion. The chaotic coupled map lattice employed in this method generates pseudo-random sequences in block diffusion phase. The experiment results and analysis have proved the novel image encryption method is practical and effective for encryption applications.

Study on the Flexural Performance of Prestressed Concrete Solid Square Piles and Resilient Clamping Connections

Yunsheng Xu,Zhongfan Chen,Ji Fan,Zhiqiang Li,Kai Zhang,Xuesong Tu 대한토목학회 2023 KSCE Journal of Civil Engineering Vol.27 No.1

The length of a single prestressed square pile is usually between 6 and 15 meters. For square piles larger than 15 meters, increasing the pile length is generally achieved by a mechanical connection. Currently, the longitudinal reinforcement ratios of square piles are the same, resulting in steel waste. To reduce steel usage in prestressed concrete solid square piles and improve construction efficiency, the safe and reliable use of two different reinforced square piles connected by resilient clamping must be ensured. In this paper, the bending test of a single square pile with different reinforcements is initially carried out. Then, the tensile performance of the resilient clamping connection joint is verified, and finally, a bending test is carried out on prestressed square piles with different reinforcements. The load?displacement curves, flexural bearing capacities and crack developments of the components are studied. The test results show that increasing the longitudinal reinforcement ratio of a single prestressed concrete solid square pile improves its crack and bending resistance to a certain extent. Resilient clamping connects the prestressed square piles with the same reinforcement and different reinforcements, and their crack resistance and bending resistance are almost the same, which demonstrates that the resilient clamping connection of different reinforcement square piles has application value. At the end of the test, the joints were intact, and the pile body was damaged before the resilient clamping connections, which indicated that the resilient clamping connections were safe and reliable and could be used as connecting joints for square piles. The failure of square piles goes through three stages: an elastic stage, a working stage with cracks and a failure stage. Compared with a single square pile, there is no obvious yield stage for a resilient clamping connected square pile.

Selection response and estimation of the genetic parameters for multidimensional measured breast meat yield related traits in a long-term breeding Pekin duck line

Xu, Yaxi,Hu, Jian,Zhang, Yunsheng,Guo, Zhanbao,Huang, Wei,Xie, Ming,Liu, Hehe,Lei, Chuzhao,Hou, Shuisheng,Liu, Xiaolin,Zhou, Zhengkui Asian Australasian Association of Animal Productio 2018 Animal Bioscience Vol.31 No.10

Objective: This study was conducted to estimate the genetic parameters and breeding values of breast meat related traits of Pekin ducks. Selection response was also determined by using ultrasound breast muscle thickness (BMT) measurements in combination with bosom breadth (BB) and keel length (KL) values. Methods: The traits analyzed were breast meat weight (BMW), body weight (BW), breast meat percentage (BMP) and the three parameters of breast meat (BB, KL, and BMT). These measurements were derived from studying 15,781 Pekin ducks selected from 10 generations based on breast meat weight. Genetic parameters and breeding value were estimated for the analysis of the breeding process. Results: Estimated heritability of BMW and BMP were moderate (0.23 and 0.16, respectively), and heritability of BW was high (0.48). Other traits such as BB, KL, and BMT indicated moderate heritability ranging between 0.11 and 0.28. Significant phenotypic correlations of BMW with BW and BMP were discovered (p<0.05), and genetic correlations of BMW with BW and BMP were positive and high (0.83 and 0.66, respectively). It was noted that BMW had positive correlations with all the other traits. Generational average estimated breeding values of all traits increased substantially over the course of selection, which demonstrated that the ducks responded efficiently to increased breast meat yield after 10 generations of breeding. Conclusion: The results indicated that duck BMW had the potential to be increased through genetic selection with positive effects on BW and BMP. The ultrasound BMT, in combination with the measurement of BB and KL, is shown to be essential and effective in the process of high breast meat yield duck breeding.

Crystallization Kinetics of PVDF Filled with Multi Wall Carbon Nanotubes Modified by Amphiphilic Ionic Liquid

Ali Bahader,Yunsheng Ding,Haoguan Gui,Yu Li,Pei Xu 한국고분자학회 2015 Macromolecular Research Vol.23 No.3

The special electric properties of the poly(vinylidene fluoride) (PVDF) is strongly dependent on its crystallinestructural morphology. In this study, modification in the crystal structure of PVDF was achieved by utilizingthe long alkyl chain ionic liquid (1-hexadecyl-3-methylimidazolium bromide, [C16mim][Br]) and ionic liquid modifiedmultiwalled carbon nanotubes (MWCNT). The developed crystal pattern was analyzed by XRD and the compatibilityand dispersion characteristics of MWCNT in the matrix was observed by FESEM. The isothermal and non-isothermalcrystallization kinetics were studied by DSC and different models namely; Avrami, Jeziorny and Ozawa were appliedto fit the data. The results demonstrate that crystal structure of PVDF is significantly changed and the dispersion ofMWCNT was enhanced with the addition of ionic liquid (IL). Kinetically, the crystallization was influenced andbecame fast due to the presence of [C16mim][Br] at the PVDF/MWCNT interface. Furthermore, the data well fittedin the model with significant linearity. The positive effect on the crystallization of PVDF may be ascribed to not onlydue to the existence of π-cation interaction between the imidazolium cation and the aromatic multiwall carbon nanotubesstructure, but also due to the electrostatic interaction between the > CF2 of the polymer backbone and imidazoliumcation, which speed up the crystallization kinetics.

Polymerized Ionic Liquid for the Regulation of Phase Structure of PLA/PCL Blends

Yiyang Zhou,Qiuyue Meng,Ping Wang,Haibing Wei,Pei Xu,Yunsheng Ding 한국고분자학회 2022 Macromolecular Research Vol.30 No.9

Polymerized ionic liquid containing block structure (PIL) has been used as regulator for the phase structure of poly(lactide) (PLA)/poly(ε-caprolactone) (PCL) blends. The phase structure, crystallization, rheology behavior and mechanical properties of PLA/PCL and PLA/PCL/PIL blends were systematically investigated. PIL could be located in PCL phase or at the PLA/PCL interface, enhancing the interaction between polymer components. The crystallization ability of PLA and PCL was simultaneously enhanced with the addition of PIL, since the plasticization effect of ionic moiety and PEO segments in PIL as well as the nucleation effect of PIL-formed ionic cluster. When PIL content was 0.5 wt%, the PLA/PCL/0.5PIL blend system exhibited much better mechanical properties than additivefree PLA/PCL blend. But as PIL contents increased, the significantly change in viscosity ratio between PLA and PCL would lead to obviously change in phase structure of PLA/PCL blend, thus the mechanical properties of the blends would be degraded.

Influence of Initial Damage Degree on the Degradation of Concrete Under Sulfate Attack and Wetting–Drying Cycles

Yujing Lv,Wenhua Zhang,Fan Wu,Huang Li,Yunsheng Zhang,Guodong Xu 한국콘크리트학회 2020 International Journal of Concrete Structures and M Vol.14 No.5

The previous researches on the degradation process of concrete under sulfate attack mainly focus on non-damaged concrete. It may lead to an excessive evaluation of the durability of the structure, which is detrimental to the safety of the structure. In this paper, three different damage degrees of concrete specimens with non-damaged (D0) and initial damage of 10% (D₁) and 20% (D₂) were prefabricated and subjected to sulfate attack and wetting–drying cycles. With the increase of sulfate attack cycles (0, 30, 60, 90, 120, 150 cycles), the changes in mass loss, relative dynamic modulus of elasticity, and the stress–strain curve were studied. The results show that the mass of the D0 specimen had been increasing continuously before 150 sulfate attack cycles. The mass of D₁ and D₂ had been increasing before 60 cycles, and decreasing after 60 cycles. At 150 cycles, the mass loss of D0, D₁, D₂ were − 1.054%, 0.29% and 3.20%, respectively. The relative dynamic modulus of elasticity (RDME) of D0 specimen increases continuously before 90 sulfate attack cycles. After 90 cycles, the RDME gradually decreases. However, for D₁ and D₂ specimens, the RDME began to decrease after 30 cycles. The damage degree has an obvious influence on the compressive strength and elastic modulus. For the D0 specimen, the compressive strength and elastic modulus increased continuously before 90 cycles and decreased after 90 cycles. The compressive strength and elastic modulus of D₁ and D₂ specimens began to decrease after 30 cycles. The stress–strain curves of concrete with different initial damage degrees were established, and the fitting results were good. Finally, based on the analysis of experimental data, the degradation mechanism of concrete with initial damage under the sulfate wetting–drying cycle was discussed.