Compressed Blocks Research Articles

Robust Learning-Based Camera Motion Characterization Scheme With Applications to Video Stabilization

This paper investigates a novel learning-based camera motion characterization scheme along with its application to the video stabilization problem. The proposed characterization scheme represents the compressed domain block motion vectors (MVs) using polar angle and magnitude histograms. Discriminative features from these two histograms are extracted and fed to a supervised learning-based hierarchical classifier for recognizing the six camera motion patterns. A comparative analysis with an existing scheme is carried out to support and validate the proposed characterization scheme. The proposed scheme works at the frame level by classifying the inter-frame camera motion patterns. This scheme is extended to classify the video segments and a novel application to video stabilization is investigated. An experimental analysis of a number of test sequences captured using a handheld video camera shows that by characterizing the smooth and jittery motions, selective video stabilization could be carried out only on those video segments that have been degraded. This approach of selective video stabilization saves considerable amount of computational time compared with running the stabilization algorithm on the entire video sequence, as proposed in the literature. The proposed strategy of using a classification scheme prior to applying the video stabilization routine offers a new paradigm to the conventional video stabilization problem. Experimental validation carried out using exhaustive search motion estimation obtained block MVs, and H.264/Advanced Video Coding-obtained MVs shows that by using the idea of selective video stabilization, up to 62% reduction in processing time can be achieved compared with video stabilization approaches wherein the entire video sequence is processed.

Macro- and Microelemental Composition and Toxicity of Unsweetened Natural Cocoa Powder in Sprague-Dawley Rats.

Unsweetened natural cocoa powder (UNCP) is a pulverized high-grade powder of compressed solid blocks which remains after extraction. Little scientific data is available concerning its safety despite the presence of potential toxic elements. Elemental composition in UNCP was analyzed with ED-XRF spectroscopy. Single oral high dose toxicity study was conducted on adult male Sprague-Dawley rats (150 g) by the limit test method. One group received water and the test group 2000 mg/kg UNCP. All animals were observed for 14 days and then euthanized for haematological, biochemical, and histopathological examinations. Thirty-eight (38) elements were found in UNCP. There was an increase in HDL cholesterol (p < 0.05), reduction in LDL cholesterol (p > 0.05), alkaline phosphatase (p < 0.05), and creatinine levels, and slight increase in urea levels (p > 0.05). Haematological changes were not significant. Histopathological analysis showed no toxic effect on the heart, liver, kidney, lungs, testis, and spleen. Intestinal erosion was observed in the test group. UNCP appears to be relatively safe when taken as a single oral high dose of 2000 mg/kg b.w.t. in rats. Caution should however be exercised at high doses due to the high elemental content of copper and high possibility of intestinal lining erosion.

Mechanical properties of sustainable soil blocks stabilised with rice husk ash, cement and lime

The provision of good quality housing is recognised as an important responsibility for welfare of common public in any country. To achieve this, building materials from natural resources are often used. The commercial exploitation of these resources often leads to various environmental problems. Hence, development of an alternative building material is of immense benefit to minimise the impact on the environment. Soil can be used for the construction of walls in many ways. However, there are few undesirable properties such as loss of strength when saturated with water, erosion due to wind or rain and poor dimensional stability. These drawbacks can be eliminated significantly by stabilising the soil with cementitious materials. Several researchers are presently looking for newer options of manufacturing stabilised compressed blocks by partially substituting cement with pozzolanic materials, which are also environmentally friendly. In this context, a comparative study is carried out on compressed stabilised soil block (CSSB) made with lime, rice husk ash (RHA) and Portland pozzolana cement. This paper discusses physical and mechanical properties of the CSSBs. Due to the use of RHA, it is observed that the final cost of the CSSB is getting reduced and also the environmental advantage of utilising the RHA may further improve the sustainability of masonry brick production.

Design and Analysis of a High Secure Video Encryption Algorithm with Integrated Compression and Denoising Block

This study investigates the design of High Secure Video Encryption with self-integrated compression and denoising block. Depending on the magnitude of the wavelet co-efficient and noise variance for each co-efficient in the hybrid compressor is estimated based on the sub band using the Maximum Likelihood Estimator and Maximum a Posterior (MAP) estimator. The Adaptive threshold is applied to each sub band co-efficient except the approximation sub band of the wavelet. The resultant will yield a superior quality by removing the noise in the video signals obtained during acquisition or transmission of video. The need of an efficient compression Block in the Video encryption is because the original video consumes more bit rate for transmission and storage. The Proposed algorithm is tested with test video considering the PSNR, MSE for evaluation.

Design and fabrication of periodic lattice-based cellular structures

ABSTRACTA methodology, which consists of design, optimization and evaluation of periodic lattice-based cellular structures fabricated by additive manufacturing, is presented. A user-friendly design framework for lattice cellular structures is developed by using a size optimization algorithm. A 3D modeling process for the lattice-based cellular structures is introduced for non-linear finite element analysis and production. The approach is demonstrated on compression block with periodic lattice-based unit cells. First, based on loading condition, most appropriate lattice layout is selected. Then, for the selected lattice layout, the lattice components are modeled as simple beam and size of the beam cross sections is optimized using in-house optimization approach for both yield and local buckling criteria. The 3D model for the optimized lattice structure is built and non-linear finite element study is conducted to predict the performance. Physical parts are 3D printed and tested to compare with the simulatio...

The effects of preferential A- and C-fibre blocks and T-type calcium channel antagonist on detection of low-force monofilaments in healthy human participants.

BackgroundA myriad of studies have argued that tactile sensibility is underpinned exclusively by large myelinated mechanoreceptors. However, the functional significance of their slow-conducting counterparts, termed C-low threshold mechanoreceptors (C-LTMRs), remains largely unexplored. We recently showed the emergence of brush- and vibration-evoked allodynia in human hairy and glabrous skin during background muscle pain. The allodynia persisted following the preferential blockade of myelinated fibres but was abolished by the preferential blockade of cutaneous C fibres, thereby suggesting a pathway involving hairy skin C-LTMRs and their functional counterparts in glabrous skin in this phenomenon. In the present study, we tested the effects of preferential A- and C-fibre conduction blocks and pharmacological blockade of T-type calcium channel Cav3.2 (expressed selectively on small-fibre LTMRs) on monofilament detection thresholds in healthy participants by compression, low-dose intradermal anaesthesia (xylocaine 0.25 %) and selective T-channel antagonist, TTA-A2.ResultsWe found that all participants could detect monofilament contacts (as low as 1.6 mN) within the innocuous tactile range regardless of the preferential blockade of myelinated fibres. Furthermore, during the compression block no subject reported a switch in modality from touch to pain. That is, the low-force monofilament contacts were always perceived as non-painful. However, there was a small but significant elevation of monofilament thresholds (~2 mN) in the glabrous skin following the compression block. Importantly, no differences were found in the thresholds across hairy and glabrous regions while the myelinated fibres were conducting or not. The preferential blockade of C fibres in the glabrous skin (with myelinated fibres intact) also resulted in a small but significant elevation of tactile thresholds. Furthermore, the use of T-channel blocker in the glabrous skin during compression block of myelinated fibres resulted in complete abolition of monofilament sensibility within the innocuous tactile range (tested up to ~20 mN).ConclusionsThese observations suggest that C-LTMRs need not be regarded as a redundant tactile system, but appear to complement normal large-myelinated-fibre tactile function. Convergent findings in glabrous and hairy skin lend support for an underlying system of innocuous mechanoreception with Cav3.2-expressing unmyelinated fibres.

Mechanical Properties and Durability of Lime and Natural Pozzolana Stabilized Steam-Cured Compressed Earth Block Bricks

The paper outlines a study carried out to analyze the effects of mixed treatment (lime–natural pozzolana) on the mechanical properties and durability of compressed earth blocks (CEB) undergone a steam curing. Effects of parameters such as conditions and the period of curing, lime and natural pozzolana content on the mechanical properties (dry tensile strength, dry and wet compressive strength, water strength coefficient) and tests of durability (capillary absorption, total absorption, wetting/drying and abrasion resistance) of CEB were investigated. The results obtained showed that steam curing of lime stabilized blocks at 75 °C for about 24 h at atmospheric pressure leads to considerably higher strengths when compared with curing under plastic film at ambient temperatures. Therefore, the mechanical strengths of steam-cured at about 24 h are near to mechanical strengths of blocks with moist-curing at 18 months. It has been shown that the addition of natural pozzolana (at contents of 10–30 %) with lime for steam-cured compressed blocks appears to produce the higher mechanical properties and sustainable than lime used alone.

COP

Protecting main memories from soft errors typically requires special dual-inline memory modules (DIMMs) which incorporate at least one extra chip per rank to store error-correcting codes (ECC). This increases the cost of the DIMM as well as its power consumption. To avoid these costs, some proposals have suggested protecting non-ECC DIMMs by allocating a portion of memory space to store ECC metadata. However, such proposals can significantly shrink the available memory space while degrading performance due to extra memory accesses. In this work, we propose a technique called COP which uses block-level compression to make room for ECC check bits in DRAM. Because a compressed block with check bits is the same size as an uncompressed block, no extra memory accesses are required and the memory space is not reduced. Unlike other approaches that require explicit compression-tracking metadata, COP employs a novel mechanism that relies on ECC to detect compressed data. Our results show that COP can reduce the DRAM soft error rate by 93% with no storage overhead and negligible impact on performance. We also propose a technique using COP to protect both compressible and incompressible data with minimal storage and performance overheads.

Motion compensation in video compression using hexagonal blocks

Modern video codecs map the frame area with square blocks to analyse inter-frame movement. This paper proposes a motion compensation algorithm based on a hexagonal form of blocks for video compression. The set partitioning in hierarchical trees algorithm based on the discrete wavelet transform has been used for residual image compression obtained after the motion compensation procedure. Our experiments showed that the usage of a hexagonal form of blocks for motion compensation has an average improvement of about 0.2 dB in terms of peak signal-to-noise ratio of the processed video sequence, the final productivity being even higher for the proposed algorithm as compared with the conventional square form of blocks.

Analytical Approach to Predict Pre–Camber Deflection of the Pre-stressed Glulam Beams

A new approach to reinforce glulam timber beams using compressed wood (CW) has been developed by the Author. The compressed wood blocks are inserted into pre-cut holes on the top of glulam beams to produce pre-camber and to generate initial tensile and compressive stresses on the top and on the bottom extreme fiber of the glulam beam, respectively. A simple analytical approach has been developed to predict pre-camber deflections of the beams reinforced with three CW blocks. Assuming that moisture-dependent expansion of the CW block creates an interactive linear pressure between the glulam beam and the CW block, this would generate a pair of eccentric force away from the neutral axis of the beam. It is shown that the pre-camber deflection predicted at midspan of the short beams with various reinforcing arrangements give good agreement with the measured pre-camber from previous experimental results.

Experimental Study of the Application of Sodium Silicate in the Windbreak and Sand Fixation Engineering

With the accelerated development of land desertification, sudden wind sand disaster, strong dust storm occurrence frequency more and more high.In the desert area where the alkali content in soil is low and there is existence of quicksand, the sand brick was prepared by using sodium silicate as chemical sand fixation adhesive materials and sodium fluosilicate as hardening agent, in order to improve the surface properties of desert land, control the spread of deserts and improve the environment of desert. In this paper, the suitable dosage of sodium fluosilicate and sodium silicate were studied,which have an important effect on compressive strength, flexural strength, block antifreeze and water absorption properties of the mortar test block.

Compressed Relaying for Two-Way Relay Networks With Correlated Sources

In this letter, a compressed relaying scheme via Huffman and physical-layer network coding (HPNC) is proposed for two-way relay networks with correlated sources (TWRN-CS). In the HPNC scheme, both sources first transmit the correlated raw source messages to the relay simultaneously. The relay performs physical-layer network coding (PNC) on the received symbols, compresses the PNC-coded symbols using Huffman coding, and broadcasts the compressed symbols to both source nodes. Then, each source decodes the other source's messages by using its own messages as side information. Compression rate and block error rate (BLER) of the proposed scheme are analyzed. Simulation results demonstrate that the HPNC scheme can effectively improve the network throughput, and meanwhile, achieve the superior BLER performance compared with the conventional non-compressed relaying scheme in TWRN-CS.

Peripheral and spinal circuits involved in mechanical allodynia.

Sensory information from nociceptors and touch receptors, such as Aβ-fiber mechanoreceptors and C-fiber low-threshold mechanoreceptors (C-LTMRs), is normally relayed and processed by separate neural circuits in the spinal cord.19 After nerve injury or inflammation, however, touch-related information is also relayed to nociceptive circuits in the superficial dorsal horn, which results in touch-evoked pain.16 Here, we depict the spinal circuits that facilitate this modality crosstalk and form the cellular basis of mechanical allodynia. A role of Aβ fibers in allodynia was originally proposed by human studies showing that compression block of Aβ fibers abolishes touch-evoked pain.3,7 Subsequent studies confirmed that after nerve injury, neurokinin-1 receptor (NK1R) expressing projection neurons in lamina I receive excitatory input from Aβ fibers via a preexisting polysynaptic connection that includes somatostatin (SOM) expressing interneurons, which also receive input from nociceptors.2,6,17 This connection is normally inhibited by dynorphin-/GAD67-expressing GABAergic interneurons in lamina II,4,6 the activity of which is controlled by polysynaptic input from Aβ fibers and by mono- and poly-synaptic inputs from Aδ- and C-fibers nociceptors. Another circuit links Aβ-fibers with lamina I NK1R− projection neurons through PKCγ+/SOM+ interneurons, central cells and SOM+ interneurons in outer lamina II. Information flow through this connection is controlled by feed-forward inhibition mediated by glycinergic and dynorphin-expressing interneurons.6,13 The Aβ-fiber subtypes that provide input to these circuits are unknown. Studies in humans14 and mice with impaired glutamate release from central synapses of C-LTMRs18 suggested that these afferents, which normally signal pleasant touch,10 might also signal mechanical allodynia. This hypothesis was, however, challenged by others who could not find differences in allodynia in mice lacking C-LTMRs11 and who were unable to induce tactile allodynia in patients lacking Aβ fibers.9 A possible explanation for this controversy is that C-LTMRs co-release the protein TAFA4, which counterbalances excitatory actions of glutamate.5 Thus, C-LTMR–specific loss of glutamatergic neurotransmission only,18 would result in a different phenotype than does the complete loss of C-LTMRs.11 C-fiber low-threshold mechanoreceptors project to lamina IIi and provide polysynaptic input to lamina I spinoparabrachial neurons,1 most of which express NK1R. They do not project to PKCγ+ neurons in the same lamina, which receive input from Aβ fibers.15 Putative C-LTMRs, as identified by means of conduction velocity and fiber diameter, also provide excitatory drive onto GABAergic islet cells in lamina II, which regulate information flow from C-fiber nociceptors via central and vertical cells to NK1R+ projection neurons.12 Existence of this C-LTMR–driven pain-inhibiting connection is consistent with recent findings suggesting an analgesic effect of C-LTMR signaling,5 which is reduced during tactile allodynia.9 Whether there is a direct crosstalk between C-LTMR– and Aβ-fiber–processing circuits or whether these 2 pathways only converge at the level of lamina I projection neurons is still unclear. However, given the evidence for a role of both fiber types in mechanical allodynia and considering the columnar organization of the spinal projections of Aβ fibers and C-LTMRs from the same skin area,8 a functional connection between these circuits seems highly likely.

Object based watermarking for H.264/AVC video resistant to rst attacks

In this paper, a compressed domain video watermarking scheme is proposed which embeds the watermark in the homogeneous moving object within a shot of video sequence to resist geometric attacks such as rotation, scaling etc. Intuitively, object based watermarking results low payload and has the least impact on visual quality since the object area is generally small and highly textured. The proposed work has two main contributions, firstly, an existing compressed domain motion coherent block detection algorithm [7] is extended to detect the moving objects within a video shot and secondly, a watermarking scheme has been proposed by embedding within the moving objects to resist RST attacks. A comprehensive set of experiments has been carried out to justify the applicability of the proposed scheme over the existing literature.

Measurement and Modelling of Water Content Effects on Thermal Properties of Compressed Soil Building Blocks

Aims: The aim of this paper was to determine the thermal conductivity and the thermal effusivity of the compressed soil building blocks as a function of their water content. Study Design: Samples with dimensions 534020 mm 3 were produced for experiment. Eight containers and an oven were used to determine the equilibrium moisture content. The thermal properties of samples were obtained using a symmetrical hot strip method device. Place and Duration of Study: University of Yaounde I and National Advanced School of Engineering, Laboratory of Energizing, Water and Environment, between March 2014 and October 2014. Methodology: Thereafter, sorption isotherm of this building material was determined using the gravimetric static method of saturated salt solutions at 30°C (ambient average temperature), and GAB equation was applied to discuss the results. Then, a symmetrical hot strip method device was used to measure the thermal conductivity and the thermal effusivity of these samples, with their Original Research Article Andre Talla; BJAST, 6(5): 520-533, 2015; Article no.BJAST.2015.107 521 water content varying from 0 to a maximum value of 0.139 kgw.kgdb .An adapted device was developed to prevent water evaporation on the lateral faces of the samples. Results:Both thermal conductivity and thermal effusivity were modelled and the experimental results were processed to evaluate these thermal properties of compressed soil building blocks.A new simplified model, based on a physical approach with assumption of an ideal shrinkage of the material during the evaporation of water, was built. Conclusion: Calculated and experimental values of thermal properties were in good agreement, with a maximum standard error of 1.671 WmKs for thermal effusivity and of 0.024 WmK for thermal conductivity. The suitability of this model for other buildings material will be further studied.

Cage-enrichment: rabbit does prefer straw or a compressed wooden block

The effect of different food related materials on the behaviour of commercial meat rabbit does was investigated to provide them enrichment. Five different treatments were tested. Control (pens without additional enrichment, C) was compared with pens containing a pinewood stick (Pine), straw in a plastic bin (Straw), a compressed wooden block (Ply) or a combination of straw and a pinewood stick (Straw+Pine). The experiment was conducted on a commercial rabbit farm using 80 cages with multiparous lactating hybrid (Hycole) rabbit does. Behavioural observations were conducted in the first 4 wk of 2 successive lactations of 6 wk each, twice a week from 15:00 to 18:30 h. Once every week the consumption of gnawing materials and soiling of the cages was scored. More does were significantly occupied with Straw and Ply than with Pine (24±20, 11±9 and 4±3% of does, respectively) for a longer duration (4±4, 2±2, 0.1±0.2% of observed time, respectively). In does of Straw+Pine group, the pinewood was barely touched and straw was preferred. It can be concluded that straw (loose material) and wooden block are used by the animals as enrichment material to gnaw or chew on. The materials remain attractive for the 2 lactations which were measured. The pinewood stick as provided in this study was rarely used and it may be questioned whether it is sufficient as enrichment material or if it should be provided in another way than hanging on the roof of the cage. This study provides a first step towards a positive list of enrichment materials that can be used in commercial rabbit farming in The Netherlands.

GPU accelerated sparse matrix‐vector multiplication and sparse matrix‐transpose vector multiplication

SummaryMany high performance computing applications require computing both sparse matrix‐vector product (SMVP) and sparse matrix‐transpose vector product (SMTVP) for better overall performance. Under such a circumstance, it is critical to maintain a similarly high throughput for these two computing patterns with the underlying sparse matrix encoded in a single storage format. The compressed sparse block (CSB) format proposed by Buluç et al. allows computing both problems on multi‐core CPUs with nearly identical throughputs. On the other hand, a direct porting of CSB to graphics processing units (GPUs), which have been recently recognized as a powerful general purpose computing platform, turns out to be inefficient. In this work, we propose a new data structure, designated as expanded CSB (eCSB), to minimize the throughput gap between SMVP and SMTVP computations on GPUs, while at the same time enable a high computing throughput. We also use a hybrid storage format to store elements in each block, which can be selected dynamically at runtime. Experimental results show that the proposed techniques implemented on a Kepler GPU delivers similar throughput on both SMVP and SMTVP and the throughput is up to 13 times faster than that of the CPU‐based CSB implementation. In addition, our eCSB procedure outperforms the previous GPU results by up to 188% and 914% in computing SMVP and SMTVP, and we validate the effectiveness of eCSB by means of wall‐clock time of bi‐conjugate gradient algorithm; our eCSB is 25% faster than Compressed Sparse Rows (CSR) and 6% faster than HYB, respectively. Copyright © 2014 John Wiley &amp; Sons, Ltd.

Testing Methods for PUF-Based Secure Key Storage Circuits

Design for test is an integral part of any VLSI chip. However, for secure systems extra precautions have to be taken to prevent that the test circuitry could reveal secret information. This paper addresses secure test for Physical Unclonable Function based systems. It investigates two secure Built-In Self-Test (BIST) solutions for Fuzzy Extractor (FE) which is the main component of PUF-based systems. The schemes target high stuck-at-fault (SAF) coverage by performing scan-chain free functional testing, to prevent scan-chain abuse for attacks. The first scheme reuses existing FE blocks (for pattern generation and compression) to minimize the area overhead, while the second scheme tests all the FE blocks simultaneously to minimize the test time. The schemes are integrated in FE design and simulated; the results show that for the first test scheme, a SAF fault coverage of 95 % can be realized with no more than 47.1k clock cycles at the cost of a negligible area overhead of only 2.2 %; while for the second test scheme a SAF fault coverage of 95 % can be realized with 3.5k clock cycles at the cost of 18.6 % area overhead. Higher fault coverages are possible to realize at extra cost (i.e., either by extending the test time, or by adding extra hardware, or a combination of both).

A CHOICE OF THE SHORTEST OF THE ALTERNATIVE COMPRESSED BLOCKS OF THE DYNAMIC HUFFMAN’S CODES IN THE FORMAT OF PNG

In the article the algorithm of generation of the alternative compressed blocks of dynamic Huffman’s codes for every block of data, choice of the shortest compressed block of alternative and iterative diminishing of its size for the improvement of the compression of images in the format of PNG is offered. The methods of the estimation of the size of block of Huffman’s codes according to the absolute frequencies of its elements are examined in details. The fragment of programs outlaying the language of C, which allows exactly to determine the size of the compressed block by principle of generation of dynamic Huffman’s codes and separate working of small frequencies of elements, using for this purpose on the average not more time, than for the close estimation of size with the use of entroping. As experiments show, realization of the offered algorithm, allows to improve the indexes of the compression of the majority of images in the format of PNG in 2 – 6 %.

Development of a radiation-hardened SRAM with EDAC algorithm for fast readout CMOS pixel sensors for charged particle tracking

CMOS pixel sensors (CPS) are attractive for use in the innermost particle detectors for charged particle tracking due to their good trade-off between spatial resolution, material budget, radiation hardness, and readout speed. With the requirements of high readout speed and high radiation hardness to total ionizing dose (TID) for particle tracking, fast readout CPS are composed by integrating a data compression block and two SRAM IP cores. However, the radiation hardness of the SRAM IP cores is not as high as that of the other parts in CPS, and thus the radiation hardness of the whole CPS chip is lowered. Especially, when CPS are migrated into 0.18-μm processes, the single event upset (SEU) effects should be also considered besides TID and single event latchup (SEL) effects. This paper presents a radiation-hardened SRAM with enhanced radiation hardness to SEU. An error detection and correction (EDAC) algorithm and a bit-interleaving storage strategy are adopted in the design. The prototype design has been fabricated in a 0.18-μm process. The area of the new SRAM is increased 1.6 times as compared with a non-radiation-hardened SRAM due to the integration of EDAC algorithm and the adoption of radiation hardened layout. The access time is increased from 5 ns to 8 ns due to the integration of EDAC algorithm. The test results indicate that the design satisfy requirements of CPS for charged particle tracking.