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Handwriting-based technologies have progressed significantly over the years. Scientists have worked beyond just recognizing pieces of plain text from paper. With archaeological advancements, discovery of ancient documents has not been as scarce as it was in the past. However, such documents are discovered in perfect condition once in a blue-moon. They are often subjected to degradation due to the perils of time and understanding them requires skilled manpower which is not easy to find. Here, an automated system is proposed for this task. The proposed system uses a new CNN-based framework to analyze the macro and micro features of an image to recognize the text. Experiments are performed with over 250K historical images of numerals from a publicly available dataset and a highest accuracy of 99.68% is obtained. The data is further subjected to different type of noises and distortions. A novel technique is used to introduce synthesized degradation in the documents. The system performs steadily in all these experimental scenarios. Comparative analysis indicates that our results are higher than the reported works and other standard techniques. [ABSTRACT FROM AUTHOR]

Memory and computationally efficient CNNs for mobile and embedded applications have sparked a lot of interest recently. Depth-wise and point-wise convolutions are used in MobileNet. In this paper, a Vedic multiplier based on the Yavadunam sutra is used to reduce hardware resource utilization at all design stages in efficient computational kernels, data pruning, memory compression, and quantization to manage the huge computation and storage difficulties of DNNs. Using the teachings of Vedic math, this multiplier will yield a higher propagation speed, lower computational complexity, reduced propagation delay, and less power consumption than multipliers based on the principles of classical mathematics. A multiplier is a critical component in Digital Signal Processing DSP frameworks, which are key components in the majority of computationally advanced frameworks. As a result, the speed and power utilization of multipliers are two critical parameters. The Vedic multiplier presented in this paper is commonly used to find decimal number squares and cubes. By modifying the existing sutra for binary numbers with the bit reduction technique, the hardware design of the Yavadunam Vedic sutra is proposed. The proposed Vedic multiplier was written in VHDL, which stands for Very High Speed Integrated Circuits Hardware Description Language. On the Spartan FPGA board, the multiplier was implemented using the Xilinx Tool and the system generator instrument. The computational complexity and propagation delay of the Vedic multiplier were lower than those of a regular multiplier. [ABSTRACT FROM AUTHOR]

In this paper, a junction-less charge plasma (CP) double-drift region (DDR) impact avalanche transit time (IMPATT) diode structure has been proposed for realizing a high-power and efficient terahertz (THz) source. A comprehensive two-dimensional (2-D) self-consistent quantum drift-diffusion (SCQDD) model has been developed by the author to study the static and THz performance of 4H-SiC based CP-DDR source designed to operate at 1.0 THz. Comparative studies on the DC and THz performance of the proposed device and conventionally doped vertical DDR IMPATT device reveal that the proposed CP-DDR can be the potential alternative of the conventional DDRs (C-DDRs), especially at the THz regime. The proposed THz CP-DDR source can be exclusively preferable over its conventional counterparts due to its easier and less complicated fabrication steps as well as equivalent performance capability with respect to the THz C-DDR sources. [ABSTRACT FROM AUTHOR]

Toe cutting of hillslopes that are intended for the expansion of the transportation networks across the hilly regions need to follow an engineered basis to avert catastrophic failures. The commonly utilized deterministic Limit Equilibrium Method (LEM) does not incorporate the uncertainties in geotechnical properties and might exhibit inappropriate or erroneous consequences of toe excavation. In order to highlight the chances of toe-excavation induced slope failures, this paper reports the outcomes of the probabilistic stability analysis while considering one-dimensional spatial variability of soil shear strength parameters. The importance of such probabilistic analyses is established by finding that 79% of the toe-excavated slopes, which are judged safe from deterministic analysis, actually exhibit high probabilities of failure. Further, the influences of coefficient of variation (CoV) and the correlation between the shear strength parameters are also highlighted. The probability of failure of the cut slopes is found to be decreased by around 70% when the correlation coefficient of the shear strength parameters decreased from +0.5 to −0.5. The permissible width of toe excavation is found to be governed by the indicators of spatial variability. It is revealed that for a CoV value of 0.2 and 0.3, a maximum horizontal extent of 7 m and 5 m can be excavated without leading to slope failure for a dimensionless correlation length up to 0.2 and 0.1, respectively. [ABSTRACT FROM AUTHOR]

With the growth in ad hoc devices, mobile ad hoc networks (MANETs) are extensively employed to realize different kinds of real-time applications. However, ad hoc devices suffer from numerous kinds of security attacks such as blackhole, grayhole, wormhole, etc. Therefore, an efficient trust management protocol is preferable. In this paper, a novel gradient boost classifier is proposed. Additionally, the hyper-parameters of gradient boost classifier are tuned using θ -non-dominated sorting genetic algorithm-III (θ NSGA-III). Optimized link state routing (OLSR) protocol is employed for experimental analysis. A multi-class dataset is collected by implementing the blackhole, grayhole, and wormhole attacks on the OLSR. Comparative analysis reveals that the proposed θ NSGA-III-based gradient boost classifier outperforms the competitive attack classification models. [ABSTRACT FROM AUTHOR]

Content Distribution Networks (CDNs) are widely used to distribute data to large number of users. Traditionally, content is being replicated among a number of surrogate servers, leading to high operational costs. In this context, Peer-to-Peer (P2P) CDNs have emerged as a viable alternative. An issue of concern in P2P networks is that of free riders, i.e., selfish peers who download files and leave without uploading anything in return. Free riding must be discouraged. In this paper, we propose a criterion, the Give-and-Take (G&T) criterion, that disallows free riders. Incorporating the G&T criterion in our model, we study a problem that arises naturally when a new peer enters the system: viz., the problem of downloading a 'universe' of segments, scattered among other peers, at low cost. We analyse this $\mathcal {N}\mathcal {P}-$hard problem, and characterize the optimal download cost under the G&T criterion. We propose an optimal algorithm, and provide a sub-optimal algorithm that is nearly optimal, but runs much more quickly; this provides an attractive balance between running time and performance. Finally, we compare the performance of our algorithms with that of a few existing P2P downloading strategies in use. We also study the computation time for prescribing the strategy for initial segment and peer selection for the newly arrived peer for various existing and proposed algorithms, and quantify cost-computation time trade-offs. [ABSTRACT FROM AUTHOR]

In unsupervised classification, kernel k-means clustering method has been shown to perform better than conventional k-means clustering method in identifying non-isotropic clusters in a data set. The space and time requirements of this method are O( n), where n is the data set size. Because of this quadratic time complexity, the kernel k-means method is not applicable to work with large data sets. The paper proposes a simple and faster version of the kernel k-means clustering method, called single pass kernel k -means clustering method. The proposed method works as follows. First, a random sample $\mathcal{S}$ is selected from the data set $\mathcal{D}$. A partition $\Pi_{\mathcal{S}}$ is obtained by applying the conventional kernel k-means method on the random sample $\mathcal{S}$. The novelty of the paper is, for each cluster in $\Pi_{\mathcal{S}}$, the exact cluster center in the input space is obtained using the gradient descent approach. Finally, each unsampled pattern is assigned to its closest exact cluster center to get a partition of the entire data set. The proposed method needs to scan the data set only once and it is much faster than the conventional kernel k-means method. The time complexity of this method is O( s + t + nk) where s is the size of the random sample $\mathcal{S}$, k is the number of clusters required, and t is the time taken by the gradient descent method (to find exact cluster centers). The space complexity of the method is O( s). The proposed method can be easily implemented and is suitable for large data sets, like those in data mining applications. Experimental results show that, with a small loss of quality, the proposed method can significantly reduce the time taken than the conventional kernel k-means clustering method. The proposed method is also compared with other recent similar methods. [ABSTRACT FROM AUTHOR]

This paper discusses concepts of a 20 kVA power converter design and key differences between discrete IGBT and module-based design approaches. Module-based power converters have been typically employed in academic and research institutes for power levels of 10 kVA and more. However, with advancement in IGBT technologies and the growing need to minimize system size and weight, designs based on discrete devices are now an attractive alternative for such power levels. A simple procedure is presented for power converter design that includes power loss evaluation, heat-sink thermal characterization, thermal model of overall system and sizing of DC link capacitor. Using the same, a state-of-the-art discrete device and module-based power converters are designed. A comparison is subsequently made, where it is shown that discrete approach yields a compact and economic design up to a power level of 20 kVA. A key objective of this work is to lay emphasis on laboratory design of power converters. This enables a graduate level student to build a converter from start and in the process gain insights into the underlying engineering design aspects. [ABSTRACT FROM AUTHOR]

This paper presents experimental results of some fresh and hardened state properties of self-compacting concrete (SCC) incorporating palm oil fuel ash (POFA). Three concrete mixes namely ordinary Portland cement (OPC) concrete i.e. concrete with 100% OPC as control, and concrete with 30% and 60% POFA having different water/binder (w/b) ratios of 0.4, 0.45 and 0.5 were prepared. Filling ability, passing ability and segregation resistance of SCC along with strength properties were determined and compared with those of the OPC based SCC. Test results revealed that replacement of POFA in general decreased the workability of concrete with acceptable range. The compressive strength, however, increased with lower w/b ratio and lower replacement of ash. The splitting tensile and flexural strength values have also followed the same trend. The results obtained and the observation made in this study suggest that POFA can suitably be used as supplementary cementing material in SCC. [ABSTRACT FROM AUTHOR]

The aim of this paper is to investigate the performance of the hybrid controller for end-point vibration suppression of a flexible manipulator, while it is tracking a desired input profile. Due to large structural vibrations, precise control of flexible manipulators is a challenging task. A hybrid controller is used to track large movements of flexible robotic manipulators, which is a combination of inverse dynamics feedforward control, command shaping and linear state feedback control. The case study of a single-link flexible manipulator is considered, where the manipulator is controlled under open-loop as well as closed-loop control scheme. In the open-loop control scheme, the aim is to test the effectiveness of the command shaper in reducing the vibration levels. Moreover, the effect of payload variations on the performance of command shapers and the importance of more robust shapers is demonstrated in this work. Under the closed-loop control scheme, the control objective is to track the large-hub angle trajectory, while maintaining low vibration levels. In comparison to collocated PD control, being reported in the literature, large reductions in tip acceleration levels as well as input torque magnitudes are observed with the proposed hybrid controller. [ABSTRACT FROM AUTHOR]

In this paper, we propose a new technique of Electrocardiogram (ECG) signal de-noising based on thresholding of the coefficients obtained from the application of the Forward Wavelet Transform Translation Invariant (FWT_TI) to each Bionic Wavelet coefficient. The De-noise De-noised ECG is obtained from the application of the inverse of BWT ( B W T) to the de-noise de-noised bionic wavelet coefficients. For evaluating this new proposed de-noising technique, we have compared it to a thresholding technique in the FWT_TI domain. Preliminary tests of the application of the two de-noising techniques were constructed on a number of ECG signals taken from MIT-BIH database. The obtained results from Signal to Noise Ratio (SNR) and Mean Square Error (MSE) computations showed that our proposed de-noising technique outperforms the second technique. We have also compared the proposed technique to the thresholding technique in the bionic wavelet domain and this comparison was performed by SNR improvement computing. The obtained results from this evaluation showed that the proposed technique also outperforms the de-noising technique based on bionic wavelet coefficients thresholding. [ABSTRACT FROM AUTHOR]

In this paper, the explicit and implicit modelling of the subsegmental excitation information are experimentally compared. For explicit modelling, the static and dynamic values of the standard Liljencrants-Fant (LF) parameters that model the glottal flow derivative (GFD) are used. A simplified approximation method is proposed to compute these LF parameters by locating the glottal closing and opening instants. The proposed approach significantly reduces the computation needed to implement the LF model. For implicit modelling, linear prediction (LP) residual samples considered in blocks of 5 ms with shift of 2.5 ms are used. Different speaker recognition studies are performed using NIST-99 and NIST-03 databases. In case of speaker identification, the implicit modelling provides significantly better performance compared to explicit modelling. Alternatively, the explicit modelling seem to be providing better performance in case of speaker verification. This indicates that explicit modelling seem to have relatively less intra and inter-speaker variability. The implicit modelling on the other hand, has more intra and inter-speaker variability. What is desirable is less intra and more inter-speaker variability. Therefore, for speaker verification task explicit modelling may be used and for speaker identification task implicit modelling may be used. Further, for both speaker identification and verification tasks the explicit modelling provides relatively more complimentary information to the state-of-the-art vocal tract features. The contribution of the explicit features is relatively more robust against noise. We suggest that the explicit approach can be used to model the subsegmental excitation information for speaker recognition. [ABSTRACT FROM AUTHOR]

In this paper, a new representation of polygonal curves is proposed. The motivation behind this proposal is to find a descriptive model with potential application in shape identification. In particular, our work addresses the problem of identifying the shape of a given polygonal curve from a set of different ones. In accordance with the proposed representation, a curve is originally described as a series of consecutive points whose connection by straight lines sketches its characteristic shape. In order to define a proper identification scheme, each series of points is mapped to a one-dimensional piecewise-linear function that assigns to each point its corresponding angle. Depending on the case under study, this assignation is performed by following two possible alternatives: (i) in the case where the shape to be identified exactly corresponds with one of the previously stored ones, a sorted sequence beginning from the minimum value of angle and ending with the maximum one is considered, and (ii) in the case where the shape to be identified is similar to one of the previously stored ones, the assignation is performed by following the sequence of points as they appear in the polygonal curve (without sorting). Under this scheme of representation, by a cyclic comparative process between the computed functions, after several steps it is decided whether the graph of any input piecewise-linear function matches the polygonal curve to be recognized within a certain tolerance. In particular, in the case of the identification of two equal shapes, this proposal exploits the well-known principle of similarity geometry, which allows a polygon to be recognized independently of scale, translation and rotation. In order to validate this representation, a comparative analysis between two different shape identification methods (Fourier descriptors and canonical representation) and the piecewise-linear proposal is performed. [ABSTRACT FROM AUTHOR]

Maximum Torque Per Voltage trajectory has been utilized only during field weakening operation of Interior Permanent Magnet (IPM) motor. In this paper, the voltage minimization control from zero-speed is proposed. Voltage minimization results in maximum torque per voltage control of IPM motor. The control implementation is also simple in comparison to current minimization, as the operation is always along the current-limit locus irrespective of operation in field-weakening. Voltage minimization technique minimizes the core losses whereas current minimization would minimize the copper losses. The mathematical model of IPM motor following voltage minimization is derived and the solution to the 4th order quartic equations is obtained using Ferrari's method. The solution obtained is utilized to develop a look-up table for vector control of IPM motor. A comparative analysis of voltage minimization and current minimization is established which is supported by simulation results and demonstrated by detailed experimental results. [ABSTRACT FROM AUTHOR]

In this paper, a cooperative game has been considered, where there is a coalition between rational players in an uncertain environment. The uncertainty occurs in terms of the quality of the raw material. The pay-offs of the players are influenced by the degree of satisfaction. Pay-offs are considered as interval numbers. A multisection technique has been applied to obtain a rational solution. In the process, it has been found that the degree of satisfaction of the rational players converges to its optimum value with the convergence of the iterations. A comparative study has been made with methods existing in the literature. [ABSTRACT FROM AUTHOR]

Bridge failure due to local scour has stimulated the enthusiasm of many researchers to study the causes of scouring and to predict the ultimate scour depth at bridge foundation. A brief review of the state of artwork of investigation conducted on local scour at bridge pier in cohesive bed material is presented. Scour process and mechanism at bridge pier in cohesive and noncohesive soil are presented. The effects of parameters influencing local scour around bridge pier is discussed. Empirical equations for predicting ultimate scour depth at bridge pier embedded in cohesive soil are outlined. Comparisons of the equations are made considering two examples: one under laboratory condition and another under field condition. [ABSTRACT FROM AUTHOR]

The present study aims to study the propagation of Rayleigh-type wave in a layer, composed of isotropic viscoelastic material of Voigt type, with the effect of yielding base and rigid base in two distinct cases. With the aid of an analytical treatment, closed-form expressions of phase velocity and damped velocity for both the cases are deduced. As a special case of the problem it is found that obtained results are in good agreement with the established standard results existing in the literature. It is established through the study that volume-viscoelastic and shear-viscoelastic material parameter and yielding parameter have significant effect on phase and damped velocities of Rayleigh-type wave in both the cases. Numerical calculations and graphical illustration have been carried out for both the considered cases in the presence and the absence of viscoelasticity. A comparative study has been performed to analyse the effect of layer with yielding base, traction-free base and rigid base on the phase and damped velocities of Rayleigh-type wave. [ABSTRACT FROM AUTHOR]

An experimental system was built to measure the gas (nitrogen and helium) flow characteristics in circular microchannels with diameters of 50, 20 and 5 μm. The Reynolds number of the flow was controlled in the large range of 15 to 2550. The highest Mach number could reach a magnitude of 0.625 and the highest Knudsen number was over 0.021. Four available empirical correlations were comparatively studied, in terms of the influence from compressibility and rarefaction. The accuracy of each correlation was investigated, and qualitative explanations were given according to the essence of fluid dynamics. The compressibility is found to be the dominant parameter in the experiments carried out. The results obtained by gas flow in holey optical fibres are helpful for the design of micro-scale pulse tube cryocoolers. [ABSTRACT FROM AUTHOR]

Drilling and milling processes are extensively used for producing riveted and bolted joints during the assembly operations of composite laminates with other components. Hole making in glass fibre reinforced plastic (GFRP) composites is the most common mechanical process, which is used to join them to other metallic structures. Bolt joining effectiveness depends, critically, on the quality of the holes. The quality of machined holes in GFRP is strongly dependent on the appropriate choice of the cutting parameters. The main purpose of the present study is to assess the influence of drilling and milling machining parameters on hole making process of woven laminated GFRP material. A statistical approach is used to understand the effects of the control parameters on the response variables. Analysis of variance (ANOVA) was performed to isolate the effects of the parameters affecting the hole making in the two types of cutting processes. The results showed that milling process is more suitable than drilling process at high level of cutting speed and low level of feed rate, when the cutting quality (minimum surface roughness, minimum difference between upper and lower diameter) is of critical importance in the manufacturing industry, especially for precision assembly operation. [ABSTRACT FROM AUTHOR]

Over 15 million tons of fly ash (FA) and 3 million tons of phosphogypsum (PG) are produced in Turkey every year. The utilization of these industrial by-product materials is important in terms of environmental and economical issues are concerned. The main purpose of this study is to evaluate the technical possibilities of incorporating FA and PG in production of building blocks. Various mixtures were prepared by incorporating these industrial wastes by replacing clay with seven different weight proportions (0%, 5%, 10%, 15%, 20%, 25% and 30%). All specimens were fired at 1000°C peak temperature. The physical and mechanical properties of all specimens such as; unit weight, compressive strength, flexural strength, dimensional stability and water absorption values were recorded. The effect of PG incorporation on the properties of samples seems to be more dominant than the effect of FA incorporation. The test results showed that; PG incorporation increased the unit weight and mechanical strength values while lowering the water absorption values. Utilization of these wastes additives is not only for conservation of clay resources, but also an alternative solution to a difficult and expensive waste disposal problems. [ABSTRACT FROM AUTHOR]

The management of inventory in a divergent supply chain involves inventory allocation/rationing in addition to the determination of order policy parameters. In the case of a stock point feeding product(s) to several downstream members, rationing mechanism can be viewed as a special case of the allocation mechanism. In a supply chain with multi-period ordering cycles, a rationing decision ensures that the entire inventory available with the feeder stock point is rationed to downstream members, whereas an allocation decision need not allocate the entire inventory available, and it is at the discretion of the decision maker at the feeder stock point to retain inventory for possible high priority demands in future periods. In any supply chain permitting backordering of demands from downstream members, the clearing of backorders is a matter of concern. This study addresses the said issue by ensuring that the feeder stock point considers the current period demand for fulfilment only after clearing the backorders with respect to the downstream members. Through this study, an attempt is made to develop mathematical models for supply chains operating with installation-specific costs (holding and shortage) and ordering policy (base stock) over a finite time horizon with and without clearing backorders in the case of rationing as well as allocating inventory to downstream members. Specifically, this work appears to be the first comparative study on allocation and rationing mechanisms in association with/without backorder clearing mechanisms in divergent supply chains, and their impact on the total supply chain cost. [ABSTRACT FROM AUTHOR]

Indian children represent a unique population of bilinguals who learn two or more languages of different isochrony. Most of their native languages are syllable-timed, whereas in school the language of learning is English, which is a stress-timed language. Exposure to multiple languages with different types of rhythmic patterns as stimulus during the development stage differentiates these children from monolinguals acquiring rhythms of a single language. Thus, to partially fill this gap, a comparative study in 115 children (aged four to eight years) and 18 adults was carried out. We investigated the frequencies around the pitch and first formant which encodes prosodic information in speech. It was found that the harmonic content in speech increases even after four years (where children exhibit or possess intelligent speech) and the spectra of adults were more distributed and had more peaks at higher frequencies as compared to the power spectra of children, where energy in higher frequency was less. This study has implications in finding speech abnormalities in Indian children with speech disorders. [ABSTRACT FROM AUTHOR]

In the present study, gas metal arc welding and flux cored arc welding were applied on SA516 Gr70 carbon steel material. Two different hybrid passes were applied, wherein flux cored wire and solid wire were applied to root pass and filler pass one by one and vice versa. Besides, two more welds of similar electrode root pass and filler pass of flux cored arc welding and gas metal arc welding were acquired. The comparative analysis was carried out in terms of macrostructure and microstructure examination, tensile testing, hardness variations, and impact testing for these classical welds and hybrid welds. The results reveal that, hybrid welds lead to better impact properties relative to classical welds. Maximum angular distortion of 2.66° was reported with classical weld of gas metal arc welding with solid wire root pass and same filler pass. The maximum impact toughness of 49 J/m3 was reported for flux cored root pass and solid wire filler pass at the weld zone. Maximum tensile strength of 596 MPa was reported for hybrid weld of solid root pass and flux cored filler pass. Microstructures are reported with the presence of different acicular ferrite and grain boundary ferrite. Maximum acicular ferrite of 61% was reported with classical weld of flux cored arc welding. [ABSTRACT FROM AUTHOR]