Visualizing the underlying trends of component latencies affecting service operation performance

This paper presents a technology agnostic method for extracting the underlying distinct patterns of variations in the overall performance of a service operation for changes to different application components supporting the service operation in a computer based service provider to consumer contract. This short paper advocates that visualizing these patterns would help in early projection of the operation's performance due to modification of the application components/processing catering to the operation, without the need of repetitive performance and load testing of the whole service. Lookup datasets against different component configurations are created to associate the variability of component processing impedances to the service operation's performance and best fit regression types are applied to enable trend extrapolation and interpolation

Nanotechnology and Nanomaterials for New and Sustainable Energy Engineering

Role of nanotechnology and nanomaterials for utilization, storage and generation of hydrogen energy, generation of environment friendly thermoelectric power, generation of geothermal energy and photovoltaic or solar energy has been explored. Graphene nanosheet has emerged as a promising material for Platinum catalyst support of fuel cell to enhance electrochemically active surface area and power generation. Graphene and graphene based nanocomposites namely graphene-Polyaniline (PANI) are explored as promising alternatives for hydrogen storage. Inorganic-organic nanocomposite electrolyte membranes comprising of nanosize inorganic building block offers higher proton conductivity, ion exchange capacity and enhanced power generation when applied in a fuel cell. Nanostructured thermoelectric material enhances the power factor and figure of merit. Inorganic (bismuth telluride) –organic (conducting polymer) nanocomposites are explored as a new class of thermoelectric material. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/3528

A Proactive Approach to Application Performance Analysis, Forecast and Fine-Tuning

A major challenge currently faced by the IT industry is the cost, time and resource associated with repetitive performance testing when existing applications undergo evolution. IT organizations are under pressure to reduce the cost of testing, especially given its high percentage of the overall costs of application portfolio management. Previously, to analyse application performance, researchers have proposed techniques requiring complex performance models, non-standard modelling formalisms, use of process algebras or complex mathematical analysis. In Continuous Performance Management (CPM), automated load testing is invoked during the Continuous Integration (CI) process after a build. CPM is reactive and raises alarms when performance metrics are violated. The CI process is repeated until performance is acceptable. Previous and current work is yet to address the need of an approach to allow software developers proactively target a specified performance level while modifying existing applications instead of reacting to the performance test results after code modification and build. There is thus a strong need for an approach which does not require repetitive performance testing, resource intensive application profilers, complex software performance models or additional quality assurance experts. We propose to fill this gap with an innovative relational model associating the operation‟s Performance with two novel concepts – the operation‟s Admittance and Load Potential. To address changes to a single type or multiple types of processing activities of an application operation, we present two bi-directional methods, both of which in turn use the relational model. From annotations of Delay Points within the code, the methods allow software developers to either fine-tune the operation‟s algorithm “targeting” a specified performance level in a bottom-up way or to predict the operation‟s performance due to code changes in a top-down way under a given workload. The methods do not need complex performance models or expensive performance testing of the whole application. We validate our model on a realistic experimentation framework. Our results indicate that it is possible to characterize an application Performance as a function of its Admittance and Load Potential and that the application Admittance can be characterized as a function of the latency of its Delay Points. Applying this method to complex large-scale systems has the potential to significantly reduce the cost of performance testing during system maintenance and evolution

Synthesis, Characterization and Performance Study of Phosphosilicate Gel-Sulfonated Poly (Ether Ether Ketone) Nanocomposite Membrane for Fuel Cell Application

Phosphosilicate gel – SPEEK (Sulfonated Poly Ether Ether Ketone) hybrid nanocomposite membranes are proposed for performance enhancement of polymer electrolyte fuel cell. The nanocomposite membranes are synthesized and characterized at 50 and 60 weight percent of inorganic loading. Phosphosilicate gel particles of varying size (sub micro to nanometer) are synthesized using sol gel approach followed by grinding using planetary ball mill for different time. Transmission Electron Microscopy (TEM) reveals less than 10 nm particle size for 20 hr grinding. Nano composite membrane having inorganic particles of size less than 10 nm exhibits higher values of proton conductivity, ion exchange capacity and water uptake compared to composite membrane comprising of larger (400 nm and above) inorganic particles. The membrane is assembled with the electrode in the unit cell and the polarization characteristics are measured at different operating temperatures. Performance study reveals that between 70 to 80 C the membrane offers best performance in terms of peak power generation and of allowable load current. For the same conditions 40-50 % nano-enhancement of peak power generation is achieved by reducing the average gel particle size from sub micro to less than 10 nm. At medium temperature (between 70 to 80 C) the nanocomposite membrane offers more than 100 enhancement of peak power generation compared to that generated by SPEEK membrane. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/2491

Nanostructures of Polyaniline with Organic and Inorganic Dopants for Sensing of Ammonia

Nanostructured samples of polyaniline (PANI) doped with different dopants (organic and inorganic) have been synthesized employing polymerization and electrodeposition. The influence of nature of dopants( organic and inorganic) and process variation on the room temperature electrical conductivity and on ammonia vapour sensing performance (response percentage and response time) has been investigated. The synthesized samples have been structurally characterized by transmission electron microscopy (TEM) and fourier transform infrared (FTIR) spectra. Regardless of type of dopants, polymerization produces nanospheres of PANI and electrodeposition leads to formation of nanorod-like structures. Among all the synthesized samples, the organic doped electrodeposited sample exhibits highest conductivity. The conductivity of the prepared samples ware measured as a function of time after exposure to ammonia indicating that the polymerized samples (both for organic and inorganic dopants) exhibit fastest response (least response time), while the electrodeposited samples show sluggish response. Thus response percentages of different samples are found to depend on the nanostructures which vary with the nature of dopants and process of preparation. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/3519

Thermoelectric Characterization of Nanostructures of Bismuth Prepared by Solvothermal Approach

Nanostructured thermoelectric materials being an emerging area of research bismuth (Bi) nanostructures have been developed by solvothermal approach with a change of solvent. Structural characterization revealed that nanorods and nanospheres like structures were generated in the process when the solvent used were only ethylene glycol (EG) and ethylene glycol with absolute ethanol (AE) in the ratio of 1:1 respectively. Electrical properties viz. conductivity (σ) and thermoelectric power(S) have been measured in the temperature range 300K to 400K. From the observed value of σ and S power factor P has been calculated. The property improved for nanosphere like structures. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/3525

Templeting of Thin Films Induced by Dewetting on Patterned Surfaces

The instability, dynamics and morphological transitions of patterns in thin liquid films on periodic striped surfaces (consisting of alternating less and more wettable stripes) are investigated based on 3-D nonlinear simulations that account for the inter-site hydrodynamic and surface-energetic interactions. The film breakup is suppressed on some potentially destabilizing nonwettable sites when their spacing is below a characteristic lengthscale of the instability, the upper bound for which is close to the spinodal lengthscale. The thin film pattern replicates the substrate surface energy pattern closely only when, (a) the periodicity of substrate pattern matches closely with the characteristic lengthscale, and (b) the stripe-width is within a range bounded by a lower critical length, below which no heterogeneous rupture occurs, and an upper transition length above which complex morphological features bearing little resemblance to the substrate pattern are formed.Comment: 5 pages TeX (REVTeX 4), other comments: submitted to Phys. Rev.Let

Dewetting of thin films on heterogeneous substrates: Pinning vs. coarsening

We study a model for a thin liquid film dewetting from a periodic heterogeneous substrate (template). The amplitude and periodicity of a striped template heterogeneity necessary to obtain a stable periodic stripe pattern, i.e. pinning, are computed. This requires a stabilization of the longitudinal and transversal modes driving the typical coarsening dynamics during dewetting of a thin film on a homogeneous substrate. If the heterogeneity has a larger spatial period than the critical dewetting mode, weak heterogeneities are sufficient for pinning. A large region of coexistence between coarsening dynamics and pinning is found.Comment: 4 pages, 4 figure

Mining recurrent concepts in data streams using the discrete Fourier transform

In this research we address the problem of capturing recurring concepts in a data stream environment. Recurrence capture enables the re-use of previously learned classifiers without the need for re-learning while providing for better accuracy during the concept recurrence interval. We capture concepts by applying the Discrete Fourier Transform (DFT) to Decision Tree classifiers to obtain highly compressed versions of the trees at concept drift points in the stream and store such trees in a repository for future use. Our empirical results on real world and synthetic data exhibiting varying degrees of recurrence show that the Fourier compressed trees are more robust to noise and are able to capture recurring concepts with higher precision than a meta learning approach that chooses to re-use classifiers in their originally occurring form

Amplification of Fluctuations in Unstable Systems with Disorder

We study the early-stage kinetics of thermodynamically unstable systems with quenched disorder. We show analytically that the growth of initial fluctuations is amplified by the presence of disorder. This is confirmed by numerical simulations of morphological phase separation (MPS) in thin liquid films and spinodal decomposition (SD) in binary mixtures. We also discuss the experimental implications of our results.Comment: 15 pages, 4 figure