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1

Image compression-encryption algorithm combining compressive sensing with log operation

Chen R.-L., Zhou Y., Luo M., Zhang A.-D., Gong L.-H.

Optica Applicata

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2018

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Vol. 48, nr 4

563--573

EN

Based on compressive sensing and log operation, a new image compression-encryption algorithm is proposed, which accomplishes encryption and compression simultaneously. The proposed image compression-encryption algorithm takes advantage of not only the physical realizability of partial Hadamard matrix, but also the resistance of the chosen-plaintext attack since all the elements in the partial Hadamard matrix are 1, –1 or log 1 = 0. The proposed algorithm is sensitive to the key and it can resist various common attacks. The simulation results verify the validity and reliability of the proposed image compression-encryption algorithm.

2

Pseudo-static experiment and analysis on seismic behavior of the RC columns strengthened by GHPFRCC

Li X., Wang J., Luo M.

Polish Maritime Research

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2015

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S 1

56--60

EN

Green high performance fiber reinforced cementitious composites (GHPFRCC) are a new class of sustainable cementitious composites, employing a high volume of fly ash to replace cement. In addition to increasing the sustainability of the construction environment, GHPFRCC exhibits a high tensile ductility and multiple cracking behaviors in the strainhardening state. These materials can effectively improve the structural energy dissipation capacity and structural durability. In this study, the optimum mixture ratio of GHPFRCC is presented established using an orthogonal experiment for a specific engineering application. The described GHPFRCC sustains the mechanical performance of concrete and is employed as the outer cladding to strengthen concrete columns. The finite element analysis of the material was based on the software ABAQUS and pseudo static experiments were conducted to exhibit retrofitting of GHPFRCC applied in the rehabilitation of seismic-damaged concrete columns. The computed and experimental results showed that GHPFRCC, while incorporating high volume fly ash, can retain significant multiple cracking behaviors. The energy dissipation capacity of the GHPFRCC reinforced concrete (RC) column is better than the comparable unreinforced column.

3

HPLC analysis of flavonoids in Lamiophlomis rotata

Luo M., Ma H., Liu X., Jiang S.

Acta Chromatographica

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2008

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Vol. 20, no. 2

247-257

EN

A simple and precise high-performance liquid chromatographic (HPLC) method has been developed for analysis of flavonoids in Lamiophlomis rotata. HPLC conditions were optimized. Baseline separation was achieved by use of a binary gradient prepared from 100:0.2 (v/v) water-trifluoroacetic acid (component A), and acetonitrile (component B). The gradient was from 20 to 35% B in 10 min, hold at 35% B for 20 min, then from 35 to 70% B in 10 min. The injection volume was 10 µL, and the detection wavelength was 366 nm. Linearity and precision were investigated. When normal leastsquares linear regression (LSLR) was compared with weighted least-squares linear regression (WLSLR), values obtained by use of the latter were much closer to the actual values, over the whole range of concentration, than those obtained by use of the former. WLSLR was therefore used in this work. This HPLC method was successfully used for analysis of the flavonoids in Lamiophlomis rotata and could be effective for quality control of the plant.

4

On (weakly) local approximation spaces of information systems

Kou H., Luo M.

Fundamenta Informaticae

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2003

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Vol. 58, nr 2

139--150

EN

A dependence space is an ordered pair consisting of a nonempty finite set and a congruence on its boolean lattice, and is viewed as a general model to deal with the indiscernibility-type incompleteness of information in rough set analysis. In this paper we consider the question when a dependence space can be locally approximated by a approximation space. We introduce a concept of (weakly) local approximation spaces and establish several important relationships among equivalences, reducts, and sub-reducts with respect to (weakly) local approximation spaces. It is shown that a dependence space is a local approximation space if and only if it is locally reducible if and only if the closure lattice generated by the dependence space is an atomic lattice. This result also gives a partial solution to an open problem posed by M. Novotny.