scholarly journals Robust Steganographic Method with Code-Controlled Information Embedding

Author(s):  
Ala Kobozeva ◽  
◽  
Arteom Sokolov ◽  

In view of the fact that most images are compressed when transmitted through telecommunica-tion systems and telecommunication systems in the energetics, from the point of view of the practical use of steganographic algorithms in real information security systems, such as their property, the ability to effectively resist a compression attack, is of great interest. This work aims at increasing the robustness of steganographic system against compression attacks to ensure the reliability of the steganographic message perception by developing a steganographic method that implements the embedding of additional information in the spatial domain of the container, us-ing the code control of the frequency components that are under perturbations resulting from the steganographic transformation. The goal was achieved using the code control of information embedding: due to preliminary additional coding of the embedded information with codewords for which the Walsh-Hadamard transformants have the specified properties, which leads to a given localization of disturbances in the Walsh-Hadamard domain of the container as a result of the information embedding. The most significant result is the steganographic method developed based on the formed theoretical basis, for which classes of codewords that provide the highest robustness against the compression attacks were constructed. The significance of the results ob-tained is that the developed method ensured a high reliability level of perception the ste-ganographic messages, significant robustness against the compression attacks, as well as sim-plicity of algorithmic implementation and high performance.

2017 ◽  
Vol 8 (2) ◽  
pp. 160-167
Author(s):  
O. G. Reutskaya ◽  
Y. M. Pleskachevsky

The most promising for mass use in gas analysis equipment are semiconductor gas sensors due to their high reliability, easy operation and relatively low cost. Power consumption in the single-sensor mode, constant heating is from 250 to 600 W average and in pulsed mode heating – ≤ 20 W. The aim of this work was to study the effectiveness of the pulsed heating for multisensor microsystems consisting of two sensors on the substrate of the nanostructured aluminum oxide, compared with the mode of constant heating.For sensitive layers were chosen compositions: SnO2+Pt+Pd at the first sensor of the microsystem and In2O3+Al2O3+Pt on the second. Measuring the sensor response in the pulse heating mode was carried out as follows. Power on each sensor microsystem was installed 1.3 mW. Then the short-term heating (theat.. = 5 s) was performed at the power 61 mW. The detected gases CO and NO2 with the concentration 200 ppm and 4 ppm, correspondingly, were submitted to the microsystem after 15 minutes. The resistance values for each of the sensor were fixed. According to the results determine the sensitivity (sensor response) the maximum value is after 60 s for the sensor with a sensing layer SnO2+Pt+Pd when exposed to CO was 670 %, and for the sensor with In2O3+Al2O3+Pt – 380 %.Advantages of using pulsed heating from the point of view of a power consumption multisensor microsystem mW-range and high performance sensors on substrates of nanostructured alumina were established.


2019 ◽  
Author(s):  
Владимир Авербух ◽  
Vladimir Averbukh ◽  
Александр Берсенев ◽  
Alexander Bersenev ◽  
Маджид Форгани ◽  
...  

In the paper we present the situation which had required visualization of a large amount of non-trivial objects, such as supercomputer’s tasks. The method of visualization of these objects was hard to find. Then we used additional information about an extra structure on those objects. This knowledge led us to an idea of grouping the objects into new generalized ones. Those new artificial objects were easy to visualize due to their small quantity. And they happened to be enough for the cognition of the original problem. That was a successful change of point of view. As a whole, our work belongs to a high-performance computing performance visualization area. It gains valuable attention from scientists over the whole world, for example [1-2].


2002 ◽  
Vol 67 (11) ◽  
pp. 1596-1608 ◽  
Author(s):  
Josef Janča

The effect of miniaturization of the separation channel on the performance of thermal field-flow fractionation (TFFF) is substantiated theoretically. The experiments carried out under carefully chosen experimental conditions proved the high performance of the separation of polymers within an extended range of molar masses from relatively low up to ultrahigh-molar-mass (UHMM) samples. The new micro-TFFF allows to achieve high resolution when applying constant field force operation, it makes easy the programming of the temperature drop which is an advantageous operational mode from the point of view of the time of analysis, and it extends considerably the range of perfectly controlled temperature of the cold wall due to a substantial decrease in the heat energy flux compared with standard size channels.


2021 ◽  
Vol 6 (51) ◽  
pp. eaaz5796
Author(s):  
I. D. Sîrbu ◽  
G. Moretti ◽  
G. Bortolotti ◽  
M. Bolignari ◽  
S. Diré ◽  
...  

Future robotic systems will be pervasive technologies operating autonomously in unknown spaces that are shared with humans. Such complex interactions make it compulsory for them to be lightweight, soft, and efficient in a way to guarantee safety, robustness, and long-term operation. Such a set of qualities can be achieved using soft multipurpose systems that combine, integrate, and commute between conventional electromechanical and fluidic drives, as well as harvest energy during inactive actuation phases for increased energy efficiency. Here, we present an electrostatic actuator made of thin films and liquid dielectrics combined with rigid polymeric stiffening elements to form a circular electrostatic bellow muscle (EBM) unit capable of out-of-plane contraction. These units are easy to manufacture and can be arranged in arrays and stacks, which can be used as a contractile artificial muscle, as a pump for fluid-driven soft robots, or as an energy harvester. As an artificial muscle, EBMs of 20 to 40 millimeters in diameter can exert forces of up to 6 newtons, lift loads over a hundred times their own weight, and reach contractions of over 40% with strain rates over 1200% per second, with a bandwidth over 10 hertz. As a pump driver, these EBMs produce flow rates of up to 0.63 liters per minute and maximum pressure head of 6 kilopascals, whereas as generator, they reach a conversion efficiency close to 20%. The compact shape, low cost, simple assembling procedure, high reliability, and large contractions make the EBM a promising technology for high-performance robotic systems.


Hydrocarbon gels contain a number of materials, such as rubber, greases, saponified mineral oils, etc., of great interest for various engineering purposes. Specific requirements in mechanical properties have been met by producing gels in appropriately chosen patterns of constituent components of visible, colloidal, molecular and atomic sizes, ranging from coarse-grained aggregates, represented by sponges, foams, emulsions, etc.; to fine-grained and apparently homogeneous ones, represented by optically clear compounds. The engineer who has to deal with the whole range of such materials will adopt a macroscopic point of view, based on an apparent continuity of all the material structures and of the distributions in space and time of the displacements and forces occurring under mechanical actions. It has been possible to determine these distributions in the framework of a comprehensive scheme in which the fundamental principles of the mechanics of continuous media provide the theoretical basis, and a testing instrument of new design, termed Rheogoniometer, the means of experimental measurement (Weissenberg 1931, 1934, 1946, 1947, 1948).


1988 ◽  
Vol 110 (4) ◽  
pp. 572-577
Author(s):  
D. J. Folenta

This paper presents a brief description and several illustrations of a new concept of marine reversing gears that utilize high-performance differentially driven epicyclic gear arrangements. This new marine power transmission has the potential to offer high reliability, simplicity, light weight, high mechanical efficiency, compactness, and technological compatibility with aircraft derivative marine gas turbine engines. Further, this new reversing gear minimizes the danger of driving the free turbine in reverse as might be the case with conventional parallel shaft reversing gear arrangements. To illustrate the weight reduction potential, a modern naval ship propulsion system utilizing an aircraft derivative gas turbine engine as the prime mover in conjunction with a conventional parallel shaft reversing gear can be compared to the subject reversing gear differential. A typical 18,642 kW (25,000 hp) marine gas turbine engine might weigh approximately 5000 kg (11,000 lb) and a conventional marine technology parallel shaft reversing gear might weigh on the order of 90,000 to 136,000 kg (200,000 to 300,000 lb). Using gear technology derived from the aircraft industry, a functionally similar differentially driven marine reversing gear might weigh approximately 13,600 kg (30,000 lb).


2012 ◽  
Vol 614-615 ◽  
pp. 1299-1302
Author(s):  
Ming Jing Li ◽  
Yu Bing Dong ◽  
Guang Liang Cheng

Multiple high speed CMOS cameras composing intersection system to splice large effect field of view(EFV). The key problem of system is how to locate multiple CMOS cameras in suitable position. Effect field of view was determined according to size, quantity and dispersion area of objects, so to determine camera position located on below, both sides and ahead to moving targets. This paper analyzes effect splicing field of view, operating range etc through establishing mathematical model and MATLAB simulation. Location method of system has advantage of flexibility splicing, convenient adjustment, high reliability and high performance-price ratio.


2015 ◽  
Author(s):  
William A. Hockberger

The Quadrimaran was invented in France in the mid-1980s by Daniel Tollet. It was an inspired design and a radical departure from traditional ship design by a man from outside the marine industry unconstrained by industry technical practices and education. Technical experts could see it would entail more structure and subsystems than other high-performance vessels, but its promise was that those penalties would be more than offset by its claimed low power and fuel consumption. A prototype/demonstrator, Alexander, was built in 1990 and operated for five years carrying and impressing many hundreds of riders. Alexander performed beautifully and appeared to bear out what was claimed. Contracts for several Quadrimarans of different sizes came quickly, especially considering how conservative an industry this is. That was significantly due to Tollet's personal charisma and skill in selling riders on the dream of carrying passengers and freight over the water fast and in comfort, yet economically. Great skepticism prevailed in some quarters, especially among naval architects knowledgeable about AMVs (advanced marine vehicles) and early-stage whole-ship design. At technical meetings, one Quadrimaran principal would comment, for example, "Why would you carry freight across the Atlantic at 38 knots on 230,000 horsepower (a reference to the planned Fastship Atlantic TG-770) when you could do it at 60 knots on only 65,000 horsepower?" Listeners would ask how this could be possible, and he would assert again that the Quadrimaran could do it, but would decline to explain. Respected technical people were working with Tollet and his company and becoming convinced of the Quadrimaran's merit. Along with the contracts came engineers with experience in ship detail design and construction (very different from early-stage whole-ship design), or responsibilities for assessing and approving ships for service. Others were with engine and equipment suppliers. Their opinion that there was something unique and special about the Quadrimaran gave it credibility and influenced more people to accept the major claims made for it. Some dismissed the most extreme claims but still accepted the idea that the Quadrimaran was capable of unusually high performance - considerably less than was being claimed, perhaps, but high nevertheless. In hindsight it is clear the skeptics were right. Results never met expectations, nor could they have. In reality, the Quadrimaran has aspects that inherently prevent it from achieving the characteristics and performance its inventor believed attainable. It cannot be built in a commercially useful size and actually perform as intended. Why this is so will be explained. A crucial fact in the Quadrimaran's history is that Daniel Tollet and his close associates believed strongly that naval architects and engineers who had been immersed in working with the existing ship types would be unable to give the Quadrimaran the very different treatment they believed it required. (Their own educations and professional work were nontechnical.) Such people were excluded from the development of Quadrimaran designs, and the belated discovery of many fundamental technical problems can be attributed to this. The company Tollet established had a number of names over the years, and other associated entities were created at times for various purposes. In this paper they are referred to collectively as QIH (Quadrimaran International Holdings) so as not to confuse things unnecessarily. In 2004 QuadTech Marine LLC was established and acquired the Quadrimaran patent (US Patent No. 5,191,849) and related intellectual property from QIH. QuadTech laid out an extensive R&D program to close gaps in the technical background and address identified issues. In the process, additional information on earlier QIH projects and products was obtained and studied, which brought to light problems that significantly compromised the Quadrimaran's prospective performance and utility. The resulting much-reduced set of potential uses and users led the company to effectively stop pursuing Quadrimaran projects after 2009. (Note: The author was Chief Technology Officer for QuadTech Marine during 2006-9, studying the Quadrimaran and planning the R&D.)


2021 ◽  
Vol 04 (1) ◽  
pp. 54-54
Author(s):  
V. R. Nigmatullin ◽  
◽  
I. R. Nigmatullin ◽  
R. G. Nigmatullin ◽  
A.M. Migranov ◽  
...  

Currently, to increase the efficiency of industrial production, high-performance and expensive technological equipment is increasingly used, in which the weakest link, from the point of view of efficiency and reliability, is the components and parts of heavily loaded tribo – couplings operating both at significantly different temperatures (conditionally under lighter conditions, the temperature difference can be 100-120 degrees) and climatic conditions (high humidity, the presence of abrasives and other chemical elements in the atmosphere). As the results of the analysis of the frequency of failures of friction units and, accordingly, the cost of their restoration reach 9-20 percent of the cost of all equipment, without taking into account significant losses of income (profit) of the enterprise from downtime. The solution of this problem is based on the study of the wear rate of friction units by the wear products accumulated in working oils, cooling lubricants, and greases. A digital equipment monitoring system (DSMT) has been developed and implemented, which includes dynamic recording of the number of wear products and oil temperature by original modern recording devices, followed by the technology of their processing and use. The system also includes methods for finding the necessary information in large data sets useful and necessary in theoretical and practical terms with a similar technique controlled by a digital monitoring system. The advantages of SMT are the ability to predict the reliability of the equipment; reduce production risks and significantly reduce inefficient costs.


Sign in / Sign up

Export Citation Format

Share Document