Subband entropy-based features for clothing invariant human gait recognition

This paper presents a wavelet-based feature extraction method for human gait recognition. The selection of features with most discriminative information is the key to improve recognition performance. The frequency domain representation of the gait image is obtained by using fast Fourier transforms. Next, a discrete wavelet transform is applied to the obtained spectrum. With single-level wavelet decomposition, four coefficients are generated. The sum of the entropy of these four wavelet coefficients is computed yielding the wavelet Entropy Image (wEnI) which is used here as the potential feature for human gait recognition. A template matching-based approach is used as the classification. The performance of the proposed wEnI feature is evaluated using whole-based and part-based methods. The experimental results show that the wEnI feature performs better compared to state-of-the-art gait features in common use.     

Side-channel attacks and learning-vector quantization

The security of cryptographic systems is a major concern for cryptosystem designers, even though cryptography algorithms have been improved. Side-channel attacks, by taking advantage of physical vulnerabilities of cryptosystems, aim to gain secret information. Several approaches have been proposed to analyze side-channel information, among which machine learning is known as a promising method. Machine learning in terms of neural networks learns the signature (power consumption and electromagnetic emission) of an instruction, and then recognizes it automatically. In this paper, a novel experimental investigation was conducted on field-programmable gate array (FPGA) implementation of elliptic curve cryptography (ECC), to explore the efficiency of side-channel information characterization based on a learning vector quantization (LVQ) neural network. The main characteristics of LVQ as a multi-class classifier are that it has the ability to learn complex non-linear input-output relationships, use sequential training procedures, and adapt to the data. Experimental results show the performance of multi-class classification based on LVQ as a powerful and promising approach of side-channel data characterization.     

Adsorption of l-histidine over mesoporous carbon molecular sieves

Mesoporous carbon, CMK-3, was prepared by large pore hexagonal mesoporous silica SBA-15. The structural order and textural properties of all the materials were studied by XRD, HRTEM, and nitrogen adsorption. Adsorption of l-histidine (His) over various porous adsorbents such as CMK-3, SBA-15, and activated carbon was studied from solutions with different pH. His adsorption was observed to be pH dependent with maximum adsorption near the isoelectric point of the amino acid. CMK-3 showed a larger amount of His adsorption as compared to SBA-15 and the conventional adsorbent, namely activated carbon. CMK-3 registers the total adsorption capacity of ca. 1350 μmol g⁻¹ which is ca. 12 times higher than the adsorption capacity of SBA-15. This large difference could be mainly due to the stronger hydrophobic interaction between the non-polar side chains of amino acids and the hydrophobic surface of the mesoporous carbon as compared to mesoporous silica. The influence of ionic strengths on the adsorption of His was also studied and the results are discussed. Nitrogen adsorption of CMK-3 after His adsorption confirmed that His molecules are tightly packed inside the mesopores.     

Application of quenching to create highly triaxial residual stresses in type 316H stainless steels

It has been proposed that highly triaxial residual stress fields may be sufficient to promote creep damage in thermally aged components, even in the absence of in-service loads. To test this proposal, it is necessary to create test specimens containing highly triaxial residual stress fields over a significant volume of the specimen. This paper presents results from an experimental and numerical study on the generation of triaxial residual stresses in stainless steel test specimens. Spray water quenching was used to generate residual stress fields in solid cylinders and spheres made from type 316H stainless steel. A series of finite element simulations and measurements were carried out to determine how process conditions and specimen dimensions influenced the resulting residual stress distributions. The results showed that highly compressive residual stresses occurred around the surfaces of the cylinders and spheres and tensile residual stresses occurred near the centre. Surface residual stresses were measured using the incremental centre hole-drilling technique, while internal residual stresses were measured using neutron diffraction. Overall there was good agreement between the predicted and measured residual stresses. The level of triaxiality was found to be very sensitive to the heat transfer coefficient, and could be controlled by adjusting the cooling conditions and changing the dimensions of the steel samples. This differed from other processes, such as welding and shot-peening, where the magnitudes and distributions of residual stresses are ill-defined and the volume of material subjected to a triaxial residual stress state is relatively small.     

An apparatus for in situ spectroscopy of radiation damage of polymers by bombardment with high-energy heavy ions

A new target station providing Fourier transform infrared (FT-IR) spectroscopy and residual gas analysis (RGA) for in situ observation of ion-induced changes in polymers has been installed at the GSI Helmholtz Centre for Heavy Ion Research. The installations as well as first in situ measurements at room temperature are presented here. A foil of polyimide Kapton HN(?) was irradiated with 1.1 GeV Au ions. During irradiation several in situ FT-IR spectra were recorded. Simultaneously outgassing degradation products were detected with the RGA. In the IR spectra nearly all bands decrease due to the degradation of the molecular structure. In the region from 3000 to 2700 cm(-1) vibration bands of saturated hydrocarbons not reported in literature so far became visible. The outgassing experiments show a mixture of C(2)H(4), CO, and N(2) as the main outgassing components of polyimide. The ability to combine both analytical methods and the opportunity to measure a whole fluence series within a single experiment show the efficiency of the new setup.     

Kinetics of oxidative cracking of n‐hexane to olefins over VOx/Ce‐Al2O3 under gas phase oxygen‐free environment

The kinetics of oxidative cracking of n‐hexane to olefins using lattice oxygen of VO_x/Ce‐Al₂O₃ is investigated. The TPR/TPO analysis shows a consistent reducibility (79%) of VO_x/Ce‐Al₂O₃ in repeated redox cycles. The total acidity of the sample is found to be 0.54 mmol/g with 22% are strong acid sites that favors olefin selectivity. The oxidative cracking of n‐hexane in a fluidized CREC Riser simulator gives approximately 60% olefin selectivity at 30% n‐hexane conversion. A kinetic model is developed considering (1) cracking, (2) oxidative dehydrogenation (ODH), and (3) catalyst deactivations. The proposed cracking mechanism considers adsorption, C–H and C–C bond fission and desorption as elementary steps and implemented by pseudo steady state hypothesis. A Langmuir‐Hinshelwood mechanism is found to represent the ODH reactions. The developed model fits the experimental data with favorable statistical indicators. The estimated specific reaction rate constants are also found to be consistent with the product selectivity data. © 2016 American Institute of Chemical Engineers AIChE J, 63: 130–138, 2017     

The magnitude of arsenic contamination in groundwater and its health effects to the inhabitants of the Jalangi--one of the 85 arsenic affected blocks in West Bengal, India

To better understand the magnitude of arsenic contamination in groundwater and its effects on human beings, a detailed study was carried out in Jalangi, one of the 85 arsenic affected blocks in West Bengal, India. Jalangi block is approximately 122 km2 in size and has a population of 215538. Of the 1916 water samples analyzed (about 31% of the total hand tubewells) from the Jalangi block, 77.8% were found to have arsenic above 10 microg l(-1) [the World Health Organization (WHO)-recommended level of arsenic in drinking water], 51% had arsenic above 50 microg l(-1) (the Indian standard of permissible limit of arsenic in drinking water) and 17% had arsenic at above 300 microg l(-1) (the concentration predicting overt arsenical skin lesions). From our preliminary medical screening, 1488 of the 7221 people examined in the 44 villages of Jalangi block exhibit definite arsenical skin lesions. An estimation of probable population that may suffer from arsenical skin lesions and cancer in the Jalangi block has been evaluated comparing along with international data. A total of 1600 biologic samples including hair, nail and urine have been analyzed from the affected villages of Jalangi block and on an average 88% of the biologic samples contain arsenic above the normal level. Thus, a vast population of the block may have arsenic body burden. Cases of Bowen's disease and cancer have been identified among adults who also show arsenical skin lesions and children in this block are also seriously affected. Obstetric examinations were also carried out in this block.     

Soil salinity of urban turf areas irrigated with saline water: I. Spatial variability

With increasing use of saline water for irrigating urban landscapes, soil salinization is becoming a concern. This study examined spatial variation in soil salinity over the length of selected fairways at five golf courses, and of large turf areas at two public parks located in west Texas and southern New Mexico. Salinity of water used for irrigation ranged from 680 to 2700 mg L⁻¹, and the sites consisted mostly of Aridisols (upland soils) or Entisols (alluvial soils). Soil salinity distribution at sites consisting of deep Aridisols was spatially independent with the coefficient of variability (CV) ranging from 24 to 42%. The sites consisting of shallow Aridisols over a calcic horizon had erratic and random soil salinity distributions with an average CV of 37%. Since soil salinity distributions in Aridisols and Alfisols appeared to be spatially independent within the distance of fairways, soil sampling adequacy can be determined by the conventional probability statistics. However, salinity distributions at Entisols sites were spatially dependant to a length of 100 m or more. In addition, the clayey Entisols used for public parks had high levels of salt accumulation (>10 dS m⁻¹ in the saturation extract) with the CV exceeding 60%. When salinity readings were stratified by soil type distribution, the CV was reduced to 28% on the average. The number of samples required to obtain the mean salinity over a typical length of fairways (250–300 m) within a deviate range of 20% averaged 6 in deep sandy Aridisols and Alfisols, and 13 each in other cases, provided that sampling of Entisols is made based on soil type distributions. These sampling requirements are greater than those for field soil moisture or saturation water contents. The spacing to collect the required number of samples over the prevailing length of fairways was between 23 and 38 m. Soil sampling for salinity appraisal is most problematic in Entisols, but can be made simple if a detailed soil map is available. In Aridisols containing a calcic horizon, it is probable to have saline spots over poorly permeable caliche.     

Studies on the thermoelectric effect in semiconducting ZnTe thin films

The thermoelectric power of Zinc Telluride (ZnTe) thin films, prepared onto glass substrate by e-beam evaporation technique in vacuum at ∼8 × 10⁻⁴ Pa, has been measured from room temperature up to 413 K with reference to pure copper. The deposition rate of the ZnTe thin films was maintained at about 2.05 nm s⁻¹. The thickness and temperature dependence of its related parameters have been studied. The Fermi-levels were determined using a non-degenerate semiconducting model. The carrier scattering index, activation energy and temperature of coefficient of activation energy have all been obtained at different ranges of thickness and temperature. All the samples were optically transparent and amorphous in structure.     

Aliasing-free compaction revisited

The design of space-efficient support hardware for built-in self-testing is of immense significance in the synthesis of present day very large-scale integration circuits and systems, particularly in the context of design paradigm shift from system-on-board to system-on-chip (SOC). The authors revisit the general problem of designing zero-aliasing (or aliasing-free) space compression hardware in relation to embedded cores-based SOC for single stuck-line faults in particular, extending the well-known concepts of conventional switching theory and of incompatibility relation to generate maximal compatibility classes utilising graph theory concepts, based on optimal generalised sequence mergeability, as developed by them in earlier works. The authors briefly present the mathematical basis of selection criteria for merger of an optimal number of outputs of the module under test for realising maximum compaction ratio in the design, along with extensive simulation results on ISCAS 85 combinational and ISCAS 89 full-scan sequential benchmark circuits, with simulation programs ATALANTA, FSIM and COMPACTEST.