An Adaptive Execution Scheme for Achieving Guaranteed Performance in Computational Grids

Nature of the resource pool in a Grid environment is heterogeneous and dynamic. Availability, load and status of the resources may change at the time of execution of an application. Therefore, in order to maintain the performance guarantee (as has been agreed upon through service level agreements (SLAs) between the client and the resource providers), an application may need to adapt to its run-time environment on the basis of resource availability and application demands. Often it may be required to migrate the application components to a new set of resources during their execution so that performance guarantee can be maintained. Objective of this paper is to present an adaptive execution scheme for achieving guaranteed performance on the basis of the SLAs. The scheme has been implemented based on the notion of performance properties and by deploying a set of autonomous agents within an integrated performance-based resource management framework.     

Rapid Synthesis of DDR Zeolite at Room Temperature

In this work, DDR zeolites were synthesized by sonochemical method without the application of any heat energy at room temperature. The synthesized zeolites were characterized by X‐ray diffraction (XRD), infrared (IR) spectral analysis, and field‐emission scanning electron microscopy (FESEM). XRD and IR results showed that phase pure DDR zeolite was started to form at room temperature after 24 h of aging and completed the formation after 5 d of aging. The Brunauer–Emmett–Teller (BET) surface area of the powder was found to be 202 m²/g. The FESEM micrograph and elemental analysis showed that desired atomic ratio of the DDR zeolite was obtained after 5 days of synthesis.     

Reducing manufacturing defect through statistical investigation in an integrated aluminium industry

Modern philosophy of quality management enhances thrust on customer satisfaction. Achieving continuous improvement in quality is a way to reach the ultimate goal of customer satisfaction. Statistical process control technique is a well-known analytical technique, which is used to solve quality problems in industry. In this paper we present how this technique was used to solve a quality problem through planned data collection and the use of statistical tool. This study was conducted in an integrated aluminium industry in India who was facing poor customer acceptance of one of their high valued product webstock, which was used to produce toothpaste tubes. Pareto analysis showed that a dragging problem, which resulted in a short length of the toothpaste tube, was the most frequent problem. High and inconsistent coefficient of friction (cof) was identified as the root cause of this dragging problem through planned data collection. A detailed and in depth study was initiated to achieve low and consistent cof. Optimum conditions of the process parameters were obtained using design of experiments viz Taguchi’s orthogonal array. The recommendations were validated by confirmatory trials. The desired range of output cof was achieved. The recommendations were implemented as a standard operating practice. As a result of implementation the occurrences of the dragging problem was substantially reduced.     

Wavelet array decomposition of images using a Hermite sieve

Generalized Hermite polynomials are used in a novel way to arrive at a multi-layered representation of images. This representation, which is centred on the creation of a new class ofwavelet arrays, is (i) distinct from what we find in the current literature, (ii) stable, and (iii) in the manner of standard transforms, transforms the image, explicitly, into matrices of coefficients, reminiscent of Fourier series,but at various scales, controlled by ascale parameter. Among the other properties of the wavelet arrays, (a) the shape of the resolution cell in the ‘phase-space’ is variable even at a specified scale, depending on the nature of the signal under consideration; and (b) a systematic procedure is given for extracting the zero-crossings from the coefficients at various scales. This representation has been successfully applied to both synthetic and natural images, including textures.     

Investigation of influence of medium ph and sulfate ion concentrations on corrosion behavior of magnesium alloy ZE41

Magnesium alloys have emerged as potential structural materials with all capabilities to even replace close contenders; aluminium alloys in weight-critical applications. High susceptibility to corrosion being the only limitation, corrosion of magnesium alloys continues to gather much attention among the material scientists worldwide. ZE41 is one such alloy of magnesium which is increasingly gaining importance as automobile and aerospace material. In the present study the influence of the medium pH and sulfate ion concentrations on the corrosion behavior of magnesium alloy ZE41 has been investigated using electrochemical techniques like the Tafel extrapolation and electrochemical impedance spectroscopy (EIS). The tests have been carried out in a range of conditions, with gradually varying pH and sulfate ion concentration. The morphology and composition of the corroded alloy surface have been determined by the scanning electron microscopy (SEM) and energy dispersion X-ray (EDX) analysis, respectively. The recorded results reflect a trend of a higher corrosion rate associated with a higher sulfate concentration at each pH and with a lower pH at each sulfate concentration.     

Effect of cellulose buffer layer on synthesis and gas permeation properties of NaA zeolite membrane

NaA zeolite membrane coating was successfully synthesized on a porous alumina substrate by hydrothermal treatment. The effects of synthesis parameters like, seeding type (ex situ, in situ), time, temperature, sol concentration, coating stages, application of intermediate layer, etc. on membrane characteristics were investigated. A continuous membrane was formed on a seeded substrate. Surface seeding (ex situ crystallization) not only accelerates the zeolite crystallization process on the support surface, but can also enhance the formation of homogeneous NaA zeolite layer. The NaA zeolite membrane with a synthesis time of 4 h shows the best microstructure and the quality of membrane was improved by employing the multi-stage coating. But the main problem associated with membrane synthesis was crack formation, and it can be reduced by applying intermediate layer, between support surface and seed layer. A thin cellulose layer was applied to the support surface before applying seed crystals. The performance of the membranes was evaluated by gas permeation measurement. The permeance of O₂, N₂ decreased as kinetic diameter of gases increased. The permselectivity of O₂/N₂ was 1.9–2.34. This value showed the molecular sieving effect of NaA zeolite membrane.     

Hermite sieve as a wavelet-like array for 1D and 2D signaldecomposition

A new class of an array of wavelet-like functions, derived from generalised Hermite polynomials and controlled by a scale parameter, has been used to create a multilayered representation for one- and two-dimensional signals. This representation, which is explicitly in terms of an array of coefficients, reminiscent of Fourier series, is stable. Among its other properties, (a) the shape of the resolution cell in the `phase-space' is variable even at a specified scale, depending on the nature of the signal under consideration; and (b) zero crossings at the various scales can be extracted directly from the coefficients. The new representation is illustrated by examples. However, there do remain some basic problems with respect to the new representation     

Pressure-induced structural phase transformations in silicon nanowires

High-pressure structural behavior of silicon nanowires is investigated up to approximately 22 GPa using angle dispersive X-ray diffraction measurements. Silicon nanowires transform from the cubic to the beta-tin phase at 7.5-10.5 GPa, to the Imma phase at approximately 14 GPa, and to the primitive hexagonal structure at approximately 16.2 GPa. On complete release of pressure, it transforms to the metastable R8 phase. The observed sequence of phase transitions is the same as that of bulk silicon. Though the X-ray diffraction experiments do not reveal any size effect, the pressure dependence of Raman modes shows that the behavior of nanowires is in between that of the bulk crystal and porous Si.     

Activity recognition system using inbuilt sensors of smart mobile phone and minimizing feature vectors

Mobile phone is becoming a very popular tool due to having various user friendly applications with all flexible options. It is highly popular for its light weight, wearable and comfortable uses. Many extrinsic habitat of human being can be monitored by the help of inbuilt sensors and its application software. This has appealing use for healthcare applications using exploitation of Ambient Intelligence for daily activity monitoring system. Here, a standard dataset of UCI HAR (University of California, Irvine, Human Activity Recognition, http://archive.ics.uci.edu) is used for analysis purpose. Naive Bayes Classifier is used for recognition of runtime activities minimizing dimension of large feature vectors. Threshold based condition box is designed by us and finally these two results are compared with that of another classifier HF-SVM (Hardware Friendly-Support Vector Machine) of previous related work.     

Mixing characteristics in microchannels with biomimetic superhydrophobic (Lotus leaf replica) walls

We demonstrate here the mixing characteristics in microchannels with a biomimetic superhydrophobic (lotus leaf replica) wall. The lotus leaf replica is fabricated using a frugal, yet efficient, double-step soft lithography method. In microchannels with a lotus leaf replica wall, the unidirectional laminar flow pertaining to the low hydrodynamics regime changes into an erratic flow field beyond a critical flow rate. We show here that such lotus leaf replica-induced erratic flow, even for low Reynolds number, can be used for enhanced mixing at the microscale. The enhancement in the mixing is quantified by the reduction in the mixing length in the microchannels with the biomimetic lotus leaf replica wall as compared to identical microchannels with flat walls. We believe that the simple cost-effective methodology for enhancing mixing in microchannels, as demonstrated here, can be integrated into lab-on-a-chip devices, which may be beneficial for applications requiring microscale mixing like DNA sequencing, enzyme reaction, and medical diagnostics.