Combined Attack Research Articles

A New Image Watermarking Algorithm Using NSCT and Harris Detector in Green Manufacturing

Based on multistage theory and NSCT, a new feature-based image watermarking scheme is proposed in this paper. Firstly, the multistage Harris detector is utilized to extract steady feature points from the host image; then, the local feature regions (LFR) are ascertained adaptively according to the feature scale theory, and they are scaled to a standard size; finally, the digital watermark are embedded into no subsample contour let low frequency area, in the low frequency regions made pseudo-Zernike moment calculation. Experimental results show that the proposed scheme is not only invisible and robust against common signals processing such as median filtering, sharpening, noise adding and JPEG compression et al, but also robust against the unclassified geometric attacks such as rotation, translation, scaling, row or column removal, shearing, local geometric distortion and combination attacks et al.

Geometric Robust Multimodal Biometric Watermarking Scheme for Copyright Protection of Digital Images

paper proposes a copyright protection system using multimodal biometrics for content protection of digital images. Two biometric traits, one physiological (face) and one behavioral (offline handwritten signature) of the legitimate owner are used as watermarks. These watermarks are embedded at different levels of resolution to the high frequency wavelet coefficients through optimal control of the embedding factor. Experimental evaluation confirms the imperceptibility and robustness of the scheme against a family of typical image distortions functions like Jpeg Compression, filtering etc as well as geometric attacks such as scaling, rotation and combined attacks.

Mitigating Type Confusion on Java Card

One of the challenges for smart card deployment is the security interoperability. A smart card resistant to an attack on a given platform should be able to guarantee the same behavior on another platform. But the current implementations do not comply with this requirement. In order to improve such standardization the authors propose a framework based on annotations with an external pre-processing to switch the Java Card Virtual Machine (JCVM) into a secure mode by activating a set of countermeasures. An example has been proposed in this paper for implementing a countermeasure against type confusion with a fault attack. Smart cards are often the target of software, hardware or combined attacks. In recent days most of the attacks are based on fault injection which can modify the behavior of applications loaded onto the card, changing them into mutant applications. This countermeasure requires a transformation of the original program byte codes which remain semantically equivalent. It needs a modification of the JCVM which stays backward compatible and a dedicated framework to deploy these applications. Thus, the proposed platform can resist to a fault enabled mutant.

A robust zero-watermarking algorithm for copyright protection of text documents

The widespread use of Internet and other communication technologies has brought about ease in reproducing, disclosing and distributing digital content. In addition to getting the benefits of information exchange, the digital community is confronted with authentication, forgery and copyright protection issues. Text is the most frequently used medium travelling over the Internet, along with images, audio and video. Majority of the content of books, newspapers, web pages, advertisements, research papers, legal documents and many other documents is basically, plain text. Therefore, copyright protection of plain text is a most important issue. In this article, we propose a robust zero-watermarking algorithm based on prepositions and double letters for copyright protection of plain text. The embedding algorithm uses occurrences of prepositions and double letters in the text to generate a key based on watermark. The extraction algorithm extracts the watermark from the noisy text to identify the original owner. Experimental results illustrate the effectiveness of the proposed algorithm on text encountering combined insertion, deletion and re-ordering attacks, both in the dispersed and localized forms. The results are also compared to a recent work on text watermarking.

A New Robust Color Image Watermarking Based on DWT and DRT

The copyright protection of multimedia information is more and more important in the digital age, digital watermarking is a solution to address the topic. This paper proposes a new robust image watermarking scheme based on discrete ridgelet transform (DRT) and discrete wavelet transform (DWT). The scheme respectively embeds a copy of color image watermark into DWT domain and DRT domain, and uses a conception of semi-watermark. Experiment results demonstrate that the watermark can resist various attacks such as adding Gaussian or Union Distribution Noise, JPEG compression, brightness adjustment, contrast adjustment, altering color balance, lens blur, zooming in or out, cropping and some combined attacks etc.

Composite chaos-based lossless image authentication and tamper localization

To improve the robustness to combined attack of signal processing plus tamper, a composite chaos-based lossless scheme for image authentication and tamper localization is proposed. A non-successive composite chaos (NSCC) is described, and its performance is analysed by some evaluation indicators. Then NSCC is employed to disturb original image and generate chaotic logo, which enhances the security and robustness of lossless image authentication scheme due to the good performance of NSCC in these aspects of randomness, complexity and ability of anti-forecast technology. Experimental results demonstrate that the proposed scheme is not only safe, but also realizes the correct extraction of logo and precise detection of tampered region position and shape under various attacks, especially signal processing plus tamper attack.

A Watermarking Scheme Based on NSCT Using Computer-Generated Hologram

A robust watermarking scheme that used computer-generated holograms as the watermark is in NSCT (NonSampled Contourlet Transform) domain was proposed. To maintain imperceptibility and robustness, a repeated embedding algorithm is adopted to embed the mark hologram into the low-frequency subband of the NSCT host image. Compared with other watermark schemes using digital holograms, the proposed algorithm has the obvious advantage in robustness The experimental results demonstrated that the proposed method had good robustness to resist common attacks such as, rotation, scaling, translation, image flipping, combined attacks, filtering, occlusion, cropping, and JPEG compression.

DISCRETE WAVELET TRANSFORM BASED CIRCUIT LAYOUT FINGERPRINTING USING CHAOTIC SYSTEM

Tight time-to-market pressure requires CAD tools to heavily involve component reuse, or intellectual property (IP) reuse, which imposes intense security concerns on IP protection. For the IP providers, it is critical to protect their products against unauthorized reproduction. Thus, circuit layout fingerprinting becomes quite important which helps the IP providers to detect which user distributes the illegal IPs. However, previous works addressing the circuit fingerprinting all have large area and runtime overhead. In this paper, a novel efficient discrete wavelet transform (DWT)-based key sensitive circuit layout fingerprinting technique using chaotic system is proposed. The new circuit layout fingerprinting technique targets to be applied after placement and routing, while before fabrication. Thus, it only slightly impacts the original design and introduces small runtime overhead as well. To further enhance the security, the chaotic system based on Fibonacci transformation is integrated. The experimental results demonstrate that our chaotic DWT-based technique largely outperforms a median-based technique for various attacks. The chaotic DWT-based technique improves the detection error rate by 68.5% for the gate swapping attack, by 65.8% for the random perturbation attack, by 54.8% for the partition-based perturbation attack and by 54.5% for the combined perturbation attack. In addition, the average wirelength overhead is only 0.0149% compared to the original design and the average runtime overhead is only 6.73 s. These demonstrate the effectiveness of our circuit layout fingerprinting technique.

Modeling security in cyber–physical systems

This paper describes a framework for modeling the security of a cyber–physical system in which the behavior of the adversary is controlled by a threat model that captures – in a unified manner – the cyber aspects (with discrete values) and the physical aspects (with continuous values) of the cyber–physical system. In particular, the framework addresses combined (dependent) vector attacks and synchronization/localization issues. The framework identifies the cyber–physical features that must be protected according to the prevailing security policy. Also, the framework can be used for formal proofs of the security of cyber–physical systems.

Beyond the Limits of DPA: Combined Side-Channel Collision Attacks

The problem of extracting the highest possible amount of key-related information using the lowest possible number of measurements is one of the central questions in side-channel attacks against embedded implementations of cryptographic algorithms. To address it, this work proposes a novel framework enhancing side-channel collision attacks with divide-and-conquer attacks such as differential power analysis (DPA). An information-theoretical metric is introduced for the evaluation of collision detection efficiency. Improved methods of dimension reduction for side-channel traces are developed based on a statistical model of euclidean distance. Experimental results confirm that DPA-combined collision attacks are superior to both DPA-only and collision-only attacks. The new methods of dimension reduction lead to further complexity improvements. All attacks are treated for the case of AES-128 and are practically validated on a widespread 8-bit RISC microcontroller.

Concrete Deterioration Mechanisms under Combined Sulfate Attack and Flexural Loading

The deterioration mechanisms of sulfate attack on concrete under sustained loading and wet-dry cycling were investigated, based on micro and macroobservations. The mass fraction of sodium sulfate solution was 6.9%. Three loading levels of 20, 40, and 60% of ultimate flexural load were considered, and the load was mechanically applied to the specimens under four-point bending. Microobservations included the analysis of the chemical products formed using thermal analysis, and the determination of the sulfate-ion content profile using the modified barium sulfate gravimetric method (chemical titration). Macroobservations primarily included visual observations and flexural strength changes. Test results showed that under alternate action of wet-dry cycling, concretes are attacked by expansive products such as ettringite and gypsum during the wetting cycle, and crystallization damage, induced by evaporation, is superposed during the drying cycle. Results also showed that the tensile stresses can increase diffusivity by initiating or developing microcracks; the compressive stresses are small compared with the concrete compressive strength, so any effect on ion transport properties is not obvious. Under simultaneous sulfate attack and flexural loading, deterioration is aggravated as the loading level increases, and this is characterized on the macroscale by the increased strength degradation. This research can provide some references for the assessment method of concrete structures under combined sulfate attack and loading action.

An update on the strategies in multicomponent activity monitoring within the phytopharmaceutical field

BackgroundTo-date modern drug research has focused on the discovery and synthesis of single active substances. However, multicomponent preparations are gaining increasing importance in the phytopharmaceutical field by demonstrating beneficial properties with respect to efficacy and toxicity.DiscussionIn contrast to single drug combinations, a botanical multicomponent therapeutic possesses a complex repertoire of chemicals that belong to a variety of substance classes. This may explain the frequently observed pleiotropic bioactivity spectra of these compounds, which may also suggest that they possess novel therapeutic opportunities. Interestingly, considerable bioactivity properties are exhibited not only by remedies that contain high doses of phytochemicals with prominent pharmaceutical efficacy, but also preparations that lack a sole active principle component. Despite that each individual substance within these multicomponents has a low molar fraction, the therapeutic activity of these substances is established via a potentialization of their effects through combined and simultaneous attacks on multiple molecular targets. Although beneficial properties may emerge from such a broad range of perturbations on cellular machinery, validation and/or prediction of their activity profiles is accompanied with a variety of difficulties in generic risk-benefit assessments. Thus, it is recommended that a comprehensive strategy is implemented to cover the entirety of multicomponent-multitarget effects, so as to address the limitations of conventional approaches.SummaryAn integration of standard toxicological methods with selected pathway-focused bioassays and unbiased data acquisition strategies (such as gene expression analysis) would be advantageous in building an interaction network model to consider all of the effects, whether they were intended or adverse reactions.

Watermarking Scheme Against Geometrical Attacks Based on Second Generation Bandelet

Image watermarking against geometric attacks is the hotspot and challenging point in the present research on watermarking. This paper analyses the characteristics of the second generation Bandelet translation, and then proposes a novel Bandelet-domain watermarking scheme against geometric attacks based on support vector regression (SVR) with the vector of feature points. The proposed scheme includes three important techniques: 1) the Bandelet based image directional flow coefficient which depicts the characteristic of the image is used to embed watermarking bits with odd-even quantization; 2) the feature points robust to geometric deformation are extracted from the watermarking image using Harris-Laplace operator, and used as the eigenvectors to train the SVR model; 3) during detection, the parameters of geometric attacks are obtained using the well trained SVR, which is used for resynchronization, then an odd-even detector is used to extract the watermark blindly. Experiment results show that the proposed scheme is well transparent and is not only robust to common image processing but also robust against some geometric attacks as well as some combined attacks.

A study on the setting technique of combination attack in top leveled men’s volleyball

A study on the setting technique of combination attack in top leveled men’s volleyball

Commensal microbiota and myelin autoantigen cooperate to trigger autoimmune demyelination

Active multiple sclerosis lesions show inflammatory changes suggestive of a combined attack by autoreactive T and B lymphocytes against brain white matter. These pathogenic immune cells derive from progenitors that are normal, innocuous components of the healthy immune repertoire but become autoaggressive upon pathological activation. The stimuli triggering this autoimmune conversion have been commonly attributed to environmental factors, in particular microbial infection. However, using the relapsing-remitting mouse model of spontaneously developing experimental autoimmune encephalomyelitis, here we show that the commensal gut flora-in the absence of pathogenic agents-is essential in triggering immune processes, leading to a relapsing-remitting autoimmune disease driven by myelin-specific CD4(+) T cells. We show further that recruitment and activation of autoantibody-producing B cells from the endogenous immune repertoire depends on availability of the target autoantigen, myelin oligodendrocyte glycoprotein (MOG), and commensal microbiota. Our observations identify a sequence of events triggering organ-specific autoimmune disease and these processes may offer novel therapeutic targets.

Τέχνη καὶ ἰδεολογία. Ὑποθέσεις σὲ δύο πίνακες τοῦ ζωγράφου Δευτερεύοντος Σίφνου (18ος-19ος αἰ.)

Τέχνη καὶ ἰδεολογία. Ὑποθέσεις σὲ δύο πίνακες τοῦ ζωγράφου Δευτερεύοντος Σίφνου (18ος-19ος αἰ.)

In Silico Synergism and Antagonism of an Anti-tumour System Intervened by Coupling Immunotherapy and Chemotherapy: A Mathematical Modelling Approach

Based on the logistic growth law for a tumour derived from enzymatic dynamics, we address from a physical point of view the phenomena of synergism, additivity and antagonism in an avascular anti-tumour system regulated externally by dual coupling periodic interventions, and propose a theoretical model to simulate the combinational administration of chemotherapy and immunotherapy. The in silico results of our modelling approach reveal that the tumour population density of an anti-tumour system, which is subject to the combinational attack of chemotherapeutical as well as immune intervention, depends on four parameters as below: the therapy intensities D, the coupling intensity I, the coupling coherence R and the phase-shifts Φ between two combinational interventions. In relation to the intensity and nature (synergism, additivity and antagonism) of coupling as well as the phase-shift between two therapeutic interventions, the administration sequence of two periodic interventions makes a difference to the curative efficacy of an anti-tumour system. The isobologram established from our model maintains a considerable consistency with that of the well-established Loewe Additivity model (Tallarida, Pharmacology 319(1):1-7, 2006). Our study discloses the general dynamic feature of an anti-tumour system regulated by two periodic coupling interventions, and the results may serve as a supplement to previous models of drug administration in combination and provide a type of heuristic approach for preclinical pharmacokinetic investigation.

Investigation of corrosion and wear properties of Fe based metal matrix composites consolidated by sintering and hot isostatic pressing

Many industrial applications, e.g. processing of polymers, suffer from high costs caused by corrosion and wear. Particularly the combination of both increases the requirements for the materials used. Corrosion resistant cold work steels were developed to withstand the combined attack. Resistance is achieved by a sufficient content of chromium in the metal matrix and by carbides dispersed in a martensitic matrix. A further gain in wear resistance is possible by adding hard phases to the steel to produce a particulate reinforced metal matrix composite (MMC). The common consolidation process for such MMCs is hot isostatic pressing, but they can also be processed by solid state or liquid phase sintering. This work focuses on detailed investigations of the properties in dependence on the processing route. The results show that the resulting corrosion and wear resistance depend not only on the processing method, but also on the incorporated hard phases in combination with the manufacturing method. In addition, the unreinforced metal matrices were compared to the MMC.

Efficient Anti-Scalable Anti-Collusion Fingerprinting

Digital fingerprinting schemes are techniques to protect the copyright of digital contents. One of the important problems is a collusion attack such that several users combine their copies of a same content to modify or delete the embedded fingerprint. Trappe et al. proposed the AND anti-collusion codes (AND-ACC) against the average attack. However, the scheme is vulnerable to linear combination attack (LCCA) and cannot support a large number of users. For this last issue, Seol and Kim highlighted a code (called SK) by extending the AND-ACC. Unfortunately, that code is weak against majority attack and LCCA. In this paper, we improve the SK scheme by adding to each group the subcode. The new code can resist average attack when the inter-group collusion is less likely than intragroup collusion due to geographic conditions. Non-blind detection statistics with the knowledge of the host and soft-threshold detection are used to identify colluders within each guilty group. Our model increases the probability of tracing )) ( log ( 1 N n O  colluders within each guilty group, where N is the fingerprinting length and n is the number of users in each group. Experiment results on the real images show that our code is robust to average attack.

Effect of multiple infestations from insect pests and other stresses on irrigated rice in the Philippines: I. Damage functions

Artificial infestation methods were employed to generate damage function graphs for guilds of three rice insect pests. In the vegetative stage, infestation of whorl maggot (Hydrellia philippina Ferino) and defoliators (a mixed population of Naranga aenescens Moore and Rivula atimeta [Swinhoe]) was applied as a combined or single pest attack. Infestation of yellow stemborer (Scirpophaga incertulas [Walker]) and leaffolder (Cnaphalocrocis medinalis [Guenée]) each were infested in one or two crop growth stages. Combinations of three stresses (four N application rates, solar radiation from the wet or dry season, and/or the presence or absence of weeds) were applied to each guild to develop more holistic economic injury levels (EILs). Slopes on the linear portion of damage curves of each pest guild became steeper with each additional stress applied, whether from multiple insect pest attack, low N, low solar radiation, or weeds. EILs can be developed by pest managers from the graphs of the damage functions for the variables quantified in this study.