Current typical adaptive steganography algorithms take the detection resistant capability into account adequately but usually cannot extract the embedded secret messages correctly when stego images suffer from compres...
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Current typical adaptive steganography algorithms take the detection resistant capability into account adequately but usually cannot extract the embedded secret messages correctly when stego images suffer from compression attack. In order to solve this problem, a framework of adaptive steganography resisting JPEG compression and detection is proposed. Utilizing the relationship between Discrete Cosine Transformation (DCT) coefficients, the domain of messages embedding is determined;for the maximum of the JPEG compression resistant ability, the modifying magnitude of different DCT coefficients caused by messages embedding can be determined;in order to ensure the completely correct extraction of embedded messages after JPEG compression, error correct codes are used to encode the messages to be embedded;on the basis of the current distortion functions, the distortion value of DCT coefficients corresponding to the modifying magnitude in the embedding domain can be calculated;to improve the detection resistant ability of the stego images and realize the minimum distortion embedding, syndrome-trellis codes are used to embed the encoded messages into the DCT coefficients that have a smaller distortion value. Based on the proposed framework, an adaptive steganography algorithm resisting JPEG compression and detection is designed, which utilizes the relationship between coefficients in a DCT block and the means of that in three adjacent DCT blocks. The experimental results that demonstrate the proposed algorithm not only has a good JPEG compression resistant ability but also has a strong detection resistant performance. Comparing with current J-UNIWARD steganography under quality factor 85 of JPEG compression, the extraction error rates without pre-compression decrease from about 50% to nearly 0, while the stego images remain a good detection resistant ability comparing with a typical robust watermarking algorithm, which shows the validity of the proposed framework. Copyrigh
Port hopping is a typical technology in moving target defense which constantly changes communication port number to confuse potential attackers and protect target *** port hopping technology,time synchronization is th...
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Port hopping is a typical technology in moving target defense which constantly changes communication port number to confuse potential attackers and protect target *** port hopping technology,time synchronization is the key problem to be solved since time synchronization can ensure communication port matching and avoid data loss in port hopping ***,in software defined network(SDN),since its architecture differs from traditional network,port hopping technology hasn't been fully applied in *** on timestamp synchronization,this paper creates a port hopping model in software defined network according to its centralized control,data plane and control plane separation as well as programmable *** timestampbased port hopping model,we design a three-party port synchronization mode by utilizing SDN controller and solve the problems in time synchronization such as clock drift and *** theoretical analysis and experimental results show that this proposed timestamp-based port hopping method can effectively resist Do S attack without adding load on SDN controller in software defined network.
Automatic return oriented programming （ROP） technology can effectively improve the efficiency of ROP constructed, but the existing research results still have some shortcomings including needing more address space, ...
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Automatic return oriented programming （ROP） technology can effectively improve the efficiency of ROP constructed, but the existing research results still have some shortcomings including needing more address space, poor generality. In order to solve these problems, this paper presents an improved ROP auto-constructor QExtd. Firstly, we design a Turing-complete language QExtdL and provide the basis of gadgets analysis. Secondly, we represent the MI instruction and realize precise process of side-effect instructions for improving the efficiency of automatic construction. At last, we establish a three-layer language conversion mechanism, making it convenient for users to construct ROP. Theoretical and experimental data show that the QExtd automatic construction method is much better than the ROPgadget based on syntax. In addition, the proposed method succeeds in constructing gadgets of ROP with the probability of 84% for programs whose sizes are more than 20 KB and whose directory is ＂/usr/bin＂ in Ubuntu, which proves that the construction capability improves significantly.
Bipartite and multipartite entangled states are of central interest in quantum information processing and foundational studies. Efficient verification of these states, especially in the adversarial scenario, is a key ...
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The structures of the neutron-rich Co69,71,73 isotopes were investigated via (p,2p) knockout reactions at the Radioactive Isotope Beam Factory, RIKEN. Isotopes of interest were studied using the DALI2 γ-ray detector ...
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The structures of the neutron-rich Co69,71,73 isotopes were investigated via (p,2p) knockout reactions at the Radioactive Isotope Beam Factory, RIKEN. Isotopes of interest were studied using the DALI2 γ-ray detector array combined with the MINOS target and tracker system. Level schemes were reconstructed using the γ−γ coincidence technique, with tentative spin-parity assignments based on the measured inclusive and exclusive cross sections. Comparison with shell-model calculations using the Lenzi-Nowacki-Poves-Sieja LNPS and PFSDG-U interactions suggests coexistence of spherical and deformed shapes at low excitation energies in the Co69,71,73 isotopes. The distorted-wave impulse approximation (DWIA) framework was used to calculate the single-particle cross sections. These values were compared with the experimental findings.
Twenty-one two-proton knockout (p,3p) cross sections were measured from neutron-rich nuclei at ∼250 MeV/nucleon in inverse kinematics. The angular distribution of the three emitted protons was determined for the fir...
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Twenty-one two-proton knockout (p,3p) cross sections were measured from neutron-rich nuclei at ∼250 MeV/nucleon in inverse kinematics. The angular distribution of the three emitted protons was determined for the first time, demonstrating that the (p,3p) kinematics are consistent with two sequential proton-proton collisions within the projectile nucleus. Ratios of (p,3p) over (p,2p) inclusive cross sections follow the trend of other many-nucleon removal reactions, further reinforcing the sequential nature of (p,3p) in neutron-rich nuclei.
For business-oriented type of short-term training courses of this new task of teaching and teaching needs, to carry out an in-depth analysis and research, detailed the demand characteristics of these new teaching curr...
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For business-oriented type of short-term training courses of this new task of teaching and teaching needs, to carry out an in-depth analysis and research, detailed the demand characteristics of these new teaching curriculum, on this basis, based on the design of a project-driven teaching practices, the implementation process is given in detail all aspects of teaching practice, and the teaching process should have the conditions and problems likely to face in-depth analysis of short-term training courses for such business-oriented type of conduct has implementation of targeted teaching a useful exploration and try.
We proposed three shortest path-attack strategies and investigated the vulnerability of three complex model networks under these path-attack strategies. The experimental results indicate that the robustness of random ...
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ISBN:
(纸本)9781510830981
We proposed three shortest path-attack strategies and investigated the vulnerability of three complex model networks under these path-attack strategies. The experimental results indicate that the robustness of random network is the weakest, but small-world network is the strongest under the shortest pathattack strategies. We also obtain that the shortest path-attack strategies are more harmful than RPA(random augmenting approach) attack strategy. These findings supplement and extend the previous attack results and can thus help us to provide some insights into the design of more robust networks.
Newly observed decay schemes of the nuclei Sb137 and Sb138 are reported. The neutron-rich Sb isotopes were produced by the in-flight fragmentation of a U238 primary beam with an energy of 345 MeV/nucleon. Several new ...
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Newly observed decay schemes of the nuclei Sb137 and Sb138 are reported. The neutron-rich Sb isotopes were produced by the in-flight fragmentation of a U238 primary beam with an energy of 345 MeV/nucleon. Several new excited states of Te137 with tentatively assigned spin-parities of (5/2−), (9/2−), and (7/2) have been established which play an important role in the evolution of neutron levels beyond N=82. The study of the β decay of Sb138 led to a considerable extension of the level scheme of Te138 including the identification of several nonyrast states. The structure of Te137 and Te138 is discussed on the basis of large-scale shell-model calculations performed using two different effective interactions.
Fairness is the prerequisite to the undergraduate thesis' s tutor allocation, which means students have the priority for choosing tutors. Because of rich experience and authoritative discourse power, the senior tu...
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Fairness is the prerequisite to the undergraduate thesis' s tutor allocation, which means students have the priority for choosing tutors. Because of rich experience and authoritative discourse power, the senior tutors are usually the objects that students compete for. In the case of information asymmetry, resources of the scarce senior tutors may not be fully utilized, resulting in the decline of thesis quality. In this paper we analyze the efficiency of the existing undergraduate thesis' s tutor allocation by using signaling game model. Finally, the improved allocation is proposed, meanwhile some advices on prompting thesis quality are given.
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