Compressed sensing

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Compressed Sensing Based Encryption Approach for Tax Forms Data

Compressed Sensing Based Encryption Approach for Tax Forms Data

Abstract —In this work we investigate the possibility to use the measurement matrices from compressed sensing as secret key to encrypt / decrypt signals. Practical results and a comparison between BP (basis pursuit) and OMP (orthogonal matching pursuit) decryption algorithms are presented. To test our method, we used 10 text messages (10 different tax forms) and we generated 10 random matrices and for distortion validate we used the PRD (the percentage root-mean-square difference), its normalized version (PRDN) measures and NMSE (normalized mean square error). From the practical results we found that the time for BP algorithm is much higher than for OMP algorithm and the errors are smaller and should be noted that the OMP does not guarantee the convergence of the algorithm. We found that it is more advantageous, for tax forms (or other templates that show no interest for encryption) to encrypt only the recorded data. The time required for decoding is significantly lower than the decryption for the entire form
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Balanced sparse model for tight frames in compressed sensing magnetic resonance imaging.

Balanced sparse model for tight frames in compressed sensing magnetic resonance imaging.

A balanced model for tight frame based compressed sensing MRI (CS-MRI) and an efficient numerical algorithm to solve it are proposed in this paper. This new model provides a unified framework to discuss the performance of the analysis and synthesis sparsity models as well as solutions between them. The impact of the balancing parameter on the reconstructed error has been extensively explored. Experiments on magnetic resonance images show that the balanced model can be no better than the analysis model whatever a balancing parameter is optimized. This observation does not change with different forms of tight frame tested in this paper.
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A reweighted ℓ1-minimization based compressed sensing for the spectral estimation of heart rate variability using the unevenly sampled data.

A reweighted ℓ1-minimization based compressed sensing for the spectral estimation of heart rate variability using the unevenly sampled data.

On the other hand, knowing as a novel sensing/sampling paradigm, the theory of Compressed Sensing (CS) asserts certain signals that are considered sparse or compressible can be possibly reconstructed from substantially fewer measurements than those required by traditional methods [17], [18]. Continued research investigations have addressed important issues across many applications spanning from data compression [19], channel coding [20], data acquisition [21], to biomedical signal and image processing. In biomedical signal/image processing, although CS has been successfully applied to a variety of topics, such as Computed Tomography (CT) reconstruction [22] and Magnetic Resonance Imaging (MRI) [23], there still remains a lack in its applications into HRV or the related analysis.
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A reconstruction method based on AL0FGD for compressed sensing in border monitoring WSN system.

A reconstruction method based on AL0FGD for compressed sensing in border monitoring WSN system.

While the potential benefits of border monitoring system based on WSN are significant, several research challenges should be addressed before practical realization. Since the detection range of the borders is significantly wide, the border monitoring WSN system usually contains thousands of senor nodes, which would generate massive amount of data. Therefore, one major challenge is how to effectively collect and transmit the massive data [3]. Due to network bandwidth limitation and energy consumption of sensor nodes in WSN, the researchers usually wish to reconstruct the original signal from a small amount of data in practical application. Moreover, with the massive data obtained from thousands of sensor nodes, the conventional signal processing framework based on the Nyquist sampling theorem would bring great difficulties to storage and transmission. Compressed Sensing (CS) theory which has been used in many fields [4-8] provides a solution for the challenges.
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Robust Watermarking Using Compressed Sensing Framework with Application to MP3 Audio

Robust Watermarking Using Compressed Sensing Framework with Application to MP3 Audio

One of the major differences between the compressed sensing framework and the other embedding approaches the proposed technique can recover the host signal and separate it blindly from the watermark. The recovered host signal SNR is tested in 3 situations, in the clean condition case, after the additive noise and after the MP3 attack. In the clean condition, an SNR of more than 90dB is obtained from the 28dB watermarked signal. This is quite remarkable and it shows that the original host signal can be almost perfectly recovered from the watermarked one. In the additive noise case, an average gain of +3dB is obtained over the noisy watermarked signal. In the MP3 attack, an average gain of +2dB is obtained over the MP3 compressed-decompressed signal. Such gains can be enhanced with a careful adjustment of the parameters of the basis pursuit denoising algorithm for the additive noise case, and by characterizing the nonlinear distortion caused by the MP3 attack.
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Hierarchical Compressed Sensing for Cluster Based Wireless Sensor Networks

Hierarchical Compressed Sensing for Cluster Based Wireless Sensor Networks

non-operational because of dead nodes, leaving the sink isolated. Energy conservation may be achieved by transmitting only the summary of the sensed data that may result loss of information. Recent reported work state that, the idea of using CS for data transmission can be advantageous in the above scenario. Naïve application of CS to a sensor network imposes extra burden over the network, hence Hybrid CS would be the most suited solution. However, determining the CS and non- CS points is crucial in such approaches to explore the true potential of the scheme. Hence a CS scheme with the ability of uniform load distribution and efficient data transmission is desired. Reduced in-network communication and optimized energy usage in such a scheme will significantly improve stability period and reduced instable region. Hence, a scheme based on compressed sensing over clustered routing structure is proposed.
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An Enhanced trusted Image Storing and Retrieval Framework in Cloud Data Storage Service Environment

An Enhanced trusted Image Storing and Retrieval Framework in Cloud Data Storage Service Environment

While compressed sensing simplifies the data acquisition at data owner, it makes the data recovery from the compressed samples a computationally intensive task. As introduced in the preliminary, it requires the data users to solve an optimization problem, which could be very challenging for the data user with computationally weak devices like smart phones. Therefore, enabling a secure data recovery service by lever- aging the cloud is of critical importance in our proposed TISR architecture. Due to the sensitive nature of data, to outsource compressed image samples directly to the cloud is prohibited. And we need to protect the image samples before outsourcing them to the cloud. The cloud should not be able to learn the private content of the image samples either before or after the image reconstruction. To securely answer all these challenges while maintaining practically acceptable performance, we propose to investigate the secure transformation based approaches to achieve secure image reconstruction outsourcing to cloud. Below we start with the introduction of TISR framework and its related security definition.
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A survey of buckling of conical shells subjected to axial compression and external pressure

A survey of buckling of conical shells subjected to axial compression and external pressure

also suggested for calculating the imperfection reduction factor for cones under axial compression. In Ref. [113], more extensive design formulas for static buckling strength of cones under axial compression were presented. The full ranges of behavior from short to long cones are covered. In Ref. [114], experiments were conducted to re-examines the concept of equivalent cylinder for: (i) elastic-plastic buckling of axially compressed cones and (ii) elastic-plastic buckling of externally pressurized cones. Two cylinders were tested. The first cylinder was subjected to axial compression only, while the second cylinder was subjected to external hydrostatic pressure.
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Rapateaceae in the state of Pará, Brazil

Rapateaceae in the state of Pará, Brazil

Rapateaceae Dumort., Anal. Fam. Pl.: 60 (1829). Herbs, terrestrial in wetlands, or epiphytic (only Epidryos Maguire). Leaves subdistichous or rosulate to distichous; leaf blades green, margins unarmed or spinescent, petioles present or absent. Inflorescences capituliform, subglobose, spicate, glomerulate or secund; scapes green, cylindrical, compressed or flattened, glabrous or sparsely pubescent, sulcate or canaliculate; spathes bivalvate or univalvate, asymmetrical or symmetrical; spikelets numerous, sessile, pedunculate or shortly pedunculate; bracteoles heterogeneous or homogenous. Flowers sessile or pedicellate; sepals 3, coriaceous or papyraceous; petals yellow; stamens 6, anthers dehiscing by 1, 2 or 4 apical or subapical pores or apical slits; ovary superior, syncarpous or apocarpous, carpels 1–3, placentation axile or basal, ovules anatropous; style 1, terminal or basal, stigma simple. Fruits loculicidal capsules. Seeds 1–3 per fruit, endosperm abundant, possibly water dispersed. Mucilage is abundant at the leaf bases (rosettes) and in the young inflorescences (from Berry 2004; Forzza & Costa 2005).
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Valorization of grape pomace residues integrating hot compressed water with biotechnology

Valorization of grape pomace residues integrating hot compressed water with biotechnology

Dilute acid hydrolysis (with sulphuric, phosphoric, maleic or oxalic acids) of hemicellulose leads essentially to high yields of xylose (nearly 95%) 14 . Unfortunately, this process may originate undesirable products catalyzing the dehydration of xylose to furfural, which can then form polymers and humins in acidic solutions. Hydrolysis of cellulose may be achieved enzymatically (more selective) or chemically (lower cost). 19 The acid-catalyzed hydrolysis of cellulose typically involves a mineral acid catalyst, but at concentrations higher than those used for hemicelluloses decomposition. As an alternative strategy, cellulose can be processed in an aqueous solution containing a dilute acid at higher temperature to convert the cellulose into equimolar amounts of levulinic and formic acids, passing through glucose and HMF as intermediates 3 20 21 . The dilute acid approach is typically favoured due to the lower acid concentrations being less corrosive on equipment and lower acid costs. 14 Several studies are also reporting the possibility of hydrolysis of cellulose by Hot Compressed Water (HCM). 22
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Testing of the Shear Strength of Compressed Material at Increased Temperature

Testing of the Shear Strength of Compressed Material at Increased Temperature

The objective of testing was to determine the shear stresses in sawdust specimens compressed to different densities and heated to a pre-defined temperature. A special test facility was designed and built and it is presented in Fig. 3 below.

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Technical Note: Use of remote sensing for landslide studies in Europe

Technical Note: Use of remote sensing for landslide studies in Europe

by Fell et al. (2008), the given answers highlight that the use of remote sensing is well established for slides (both ro- tational and translational) and extremely low and very slow movements, especially in large scale applications. However, recent advances in remote sensing technology have brought the possibility of successful applications also for landslides of every other typology and velocity (Table 2). Similarly, re- mote sensing is employed to investigate a large variety of landslide parameters: some of them are very well established (e.g. geometry, activity, velocity, displacement and deforma- tion), but in a few cases new emerging remote sensing tech- niques (such as airborne geophysics) are currently applied to investigate also other parameters (e.g. detection of pecu- liar morphological and geological structures or monitoring of volume changes) (Table 2).
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A Robust False Matching Points Detection Method for Remote Sensing Image Registration

A Robust False Matching Points Detection Method for Remote Sensing Image Registration

Image registration is a key step in remote sensing image processing and is widely used in image stitching, change detection, image fusion, and other applications. However, given the influences of illumination, imaging angle, geometric distortions, and others, false matching points are still observed in all image registration algorithms. Scale-invariant feature transform (SIFT) (Lowe, 2004) and its improvements (Bay et al., 2006; Ke and Sukthankar, 2004; Li et al., 2011; Mikolajczyk and Schmid, 2005) also demonstrate false matching points. Therefore, false matching points detection is an important step in remote sensing image registration.
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New trends in plasmonic (bio)sensing

New trends in plasmonic (bio)sensing

The concept of dual modal SERS-fluorescence nanoprobes (Lee et al. 2012) can be improved with the emerg- ing analytical technique dual-mode shell-isolated nanoparticle enhanced Raman scattering - shell-isolated nanoparticle enhanced fluorescence (SHINERS-SHINEF) (Fang et al. 2015, Li et al. 2017). SHINERS (Li et al. 2010) and SHINEF (Guerrero and Aroca 2011) are plasmon-enhanced spectroscopy phenomena based on plasmonic metallic nanostructures (most commonly silver and gold) coated with silica, called SHINs (shell-isolated nanoparticles) (Li et al. 2010, 2013). It is known that a continuous transition from fluores- cence enhancement to fluorescence quenching is observed by varying the molecule-nanoparticle distance. The optimum molecule-nanoparticle separation to achieve enhanced fluorescence is reached by using spac- ers (Gersten and Nitzan 1981). Since the distance between a molecule and the nanostructure can be easily controlled by tuning the silica shell thickness, SHINs are ideal to promote SHINERS and/or SHINEF (Li et al. 2010, Guerrero and Aroca 2011). Their advantages include: i) silica shell thickness control, with a nanometer precision (Li et al. 2013), preventing the quenching effect and enhancing the fluorescence sig- nal; ii) good dispersity of the SHINs in organic solvents and water for applications in solution; iii) the silica shell protects the metal core from chemical reactivity with the analytes, which can reduce the potential cy- totoxicity of metal nanoparticles for applications in living cells (Li et al. 2017). For instance, the dual-mode SHINERS-SHINEF was first used to confirm that scattering scales as the fourth power of the local field enhancement while the fluorescence is proportional to the square of the local field enhancement (Guerrero et al. 2012). The latter was proven by collecting SHINERS and SHINEF spectra from the same molecular system (crystal violet solution, excited with laser line at 514.5 nm), as displayed in Fig. 15. Therefore, the dual-mode SHINERS-SHINEF (Li et al. 2017) is a promising tool with potential applications in improving the performance of (bio)sensing platforms and nanoprobes.
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A Technical Review of Compressed Natural Gas as an Alternative Fuel for Internal Combustion Engines

A Technical Review of Compressed Natural Gas as an Alternative Fuel for Internal Combustion Engines

Compressed natural gas (CNG) has long been used in stationary engines, but the application of CNG as a transport engines fuel has been considerably advanced over the last decade by the development of lightweight high-pressure storage cylinders [5] . Any researcher [42 - 46] was researched about the compressed natural gas as alternative fuel motivated by the economic, emissions and strategic advantages of alternative fuels. Several alternative fuels have been recognized as having a significant potential for producing lower overall pollutant emissions compared to gasoline and diesel fuel. Natural gas, which is composed predominately by has been identified as a leading candidate for transportation applications among these fuels for several reasons [42-44] . Shasby [42] identified tree reason, the first reason is availability, the second attraction reason of natural gas is its environmental compatibility and the third attraction reason of natural gas is that it can be used in conventional diesel and gasoline engines. According to [5] , operating costs are another reasons, where natural gas powered vehicles theoretically have a significant advantage over petroleum-powered vehicles, the basis for this argument is the lower cost per energy unit of natural gas as compared to petroleum. The argument is somewhat more complex than this, however. While it is true that in the vast majority of the country natural gas is cheaper than gasoline or diesel, the analysis plays out differently. Compressed Natural Gas (CNG) is attractive for five reasons. (1) It is the only fuel cheaper than gasoline or diesel. (2) It has inherently lower air pollution emissions. (3) It has lower greenhouse gas emissions. (4) Its use extends petroleum supplies, and (5) there are large quantities of the fuel available in North America. The difficulties with CNG arise from vehicle range, fuel storage, infrastructure costs, and ensuring sufficient supply. The importance of range as
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As dimensões do Valor da Marca Caso Sensing Future

As dimensões do Valor da Marca Caso Sensing Future

The present report is split into two parts, the first being of theoretic nature, as to explain some of the concepts inserted on the second part, this one being of a more practical nature. In the first part a framing is done of the current context relative to the addressed themes, namely what comes to Brand Management, Communication through the Internet (Internet Marketing) and Relational Marketing. Since the hosting organization is a startup, the tasks performed are mainly related to communication and managing of the brand. Taking into account the current conjecture, the internet has become an important tool to reach the public that is to be worked on. For instance, on the second part a presentation of Sensing Future is made, explaining its current situation on the market it's inserted in. For the purpose of clarifying the context, an internal analysis of the organization is made, supported on a technique of the qualitative study method - the interview. Afterwards, the primary performed tasks and their contextualization are made known.
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Large scale privacy preserving bluetooth sensing

Large scale privacy preserving bluetooth sensing

An infrastructure of this nature can be built from scratch given the increasingly smaller cost of the technological equipment required. Alternatively, it can be built upon the large number of Bluetooth scanners already present in some urban environments. These scanners are owned by many entities and they serve very diverse purposes, such as proximity marketing, device localization or OBEX-based interaction. They could be used, without any additional cost, as nodes in a large scale collaborative sensing infrastructure. Each node would still scan for its own purposes, but it would also share part of the generated data with a central service that would then be able to produce aggregate information of mutual interest. Both strategies make the creation of this type of infrastructure relatively simple and feasible in the short term.
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A Wearable High-Accuracy Hand Sensing System

A Wearable High-Accuracy Hand Sensing System

The evaluation interface becomes one of the most important interfaces in the developed Android application since it actually allows the user to obtain the absolute measurements of the [r]

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Resonance Based Micromechanical Cantilever for Gas Sensing

Resonance Based Micromechanical Cantilever for Gas Sensing

This paper deals with an original methodology of measurement of the major polluting gas carbon dioxide. The gravimetric sensor works by adsorbing the CO2 molecules in ZnO sensing layer, which alters the overall mass of the sensing element and thereby changing the resonant frequency of the cantilever used. This frequency shift is used to identify the quantity of CO2 molecules present in the atmosphere. Here a micro-cantilever beam is fabricated using selective coatings on the surface to adsorb CO2 molecules.

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Natural Gas Container Transportation: the Alternative Way to Solve the World’s Energy Transportation Problems

Natural Gas Container Transportation: the Alternative Way to Solve the World’s Energy Transportation Problems

Abstract. The container gas transportation for low and medium level consumers as an alternative to pipelines is considered. The options for gas supply schemes, based on road and rail transport are given. The advantages and disadvantages of both types of gas transporting are described, the areas of their effective using are separated in the article. Promising implementations of technology in environment of economic crisis and also considering world trends of energy development are presented. The most advanced organization of compressed gas condensate transportation of unprepared gas fields in large diameter universal cylindrical balloons (up to 1000 mm) are reasoned.
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