Harmonic Resonance Analysis for Wind Integrated Power System and Optimized Filter Design

As the contribution of renewable energy sources is increasing year over year, the effect of harmonics on power system becomes important, and it requires special attention. In conventional power sources, the harmonics is not generated at the source side; only load side is contributing in the harmonics. But renewable energy sources, particularly wind and solar, are based on power electronic devices, so it generates harmonics. This harmonics may have an adverse effect on the system. Harmonic resonance is one of the phenomena, due to which the harmonics are amplified and give rise to several trivial issues. Various methods are used to control the harmonics in the system. Harmonic filter is one of the simple ways to absorb the harmonics generated at load and generation side. Various filter designs have been found in literature as well as in the field. The filters are classified according to their design, construction and operation method. There are two main categories, active filters and passive filters. The passive filters are widely used due to its simplicity and lesser cost. However, to achieve the better performance, it is also used with active filters, and this combination is known as hybrid filter. The response of filters is modified as per the system requirement using various techniques. In this work, the impedance characteristics of various filters are discussed and analysed. Also, how the control structure of power electronic devices affects or modifies the output impedance of converter is also discussed

Optical Waveguide for Measurement Application

The chapter provides the analysis of the behaviour of Mach Zehnder interferometer waveguide (MZIW) sensing structure and establishes the general design principles. Photonics interferometers have been widely used because of their highly sensitive detection technique. The present study is based on the MZIW structure for sensing application and deals with interferometer single-mode transmission. Theoretically, short wavelength and high difference in index (Δη) results in the low depth of the evanescence wave and increase in sensitivity. MZIW under consideration is very small in size hence it is very difficult to guide the light into waveguide. The output monitor detection sensitivity of the entire MZI structure depends on light-guiding efficiency. To maintain minimum losses at various micro-branches of the entire MZIW structure, effective light propagation is important and it is a critical parameter of the entire interferometer. Various tests have been carried out to study the effects of the Y branch angle variation on light guiding into the MZIW structure especially in measurement application

Facies characterisation of a shallow-water deltaic succession: the Upper Jurassic Wagad Sandstone Formation of Kachchh, western India

Ancient deltaic facies are difficult to differentiate from tidally influenced shallow-marine facies. The Wagad Sandstone Formation of the Wagad Highland (eastern Kachchh Basin) is typified by offshore and deltaic facies with sedimentary characteristics that represent different conditions of hydrodynamics and related depositional processes. The study area, the Adhoi Anticline, constitutes a ~154-m-thick, shale-dominated sequence with progressive upward intercalations of bioturbated micritic sandstone and quartz arenite. Two thick Astarte beds (sandy allochemic limestone), with an erosional base and gravel blanketing, illustrate tidal amplification and high-energy stochastic events such as storms. Sedimentological characteristics document three depositional facies: an offshore, shale-dominated sequence prograding to proximal prodeltaic micritic sandstone and quartz arenite with sandy allochemic limestones, further prograding to mouth bars and abandoned channel deposits. The Wagad Sandstone Formation displays depositional environmental conditions that are dissimilar from those of coeval deposits in Kachchh sub-basins as well as on regional and global scales. This is attributed to a reactivation of the Kachchh Mainland and South Wagad faults which resulted in detachment and uplift of the Wagad block which then experienced prograding deltaic conditions

Rediscovery, resurrection and lectotypification of endemic Isoetes sampathkumarnii L. N. Rao from India

An interesting species of Isoetes was collected from Jambughoda, Wildlife Sanctuary, Gujarat. After a review of literature and comparison of the morphological characters with type specimens, it was identified as I. sampathkumarnii L. N. Rao. It is endemic species of south India and rediscovered after a lapse of 63 years. The species shows several features that make it unique in the genus. Earlier, I. sampathkumarnii was also treated as synonym of I. coromandelina L.f. and I. sahyadrii Mahabala. However, it has an idiosyncratic velum character and spore ornamentation that makes it different from other species. Hence, the authors resurrected it as a distinct species. The original material is ambiguous hence, a lectotype of I. sampathkumarnii has been designated here

Deep Water Massive Sands : grain to depositional element scale analysis of their internal character

Deep Water Massive Sands (DWMS) are ubiquitous in the modern and ancient sedimentary rock record, where they form important hydrocarbon reservoirs. Despite their economic importance and decades of research concerning their origin and internal character, they remain relatively enigmatic. This study, therefore, aims to shed light on their internal character and the processes responsible for their formation, and the implications this may have on hydrocarbon exploration and production. The study utilises outcrop (Grès de Peïra Cava and Numidian Flysch) and subsurface (East Brae Field) data to investigate the sedimentary character of DWMS at the grain, bed and element scale, by employing digital image analysis, vertical and lateral facies analysis, geostatistics (Markov chain and Entropy analysis) and static heterogeneity coefficients. From the analysis of the data, the following contribution to the field of deep-water sedimentology can be made: (1) three varieties of massive sands have been identified: ungraded and graded massive sands, and massive sands with patchy texture; (2) massive sands are characterised by a variety of grain size trends within the different grain size percentiles; (3) oblique-to-flow and high imbrication angle is the typical fabric character; (4) massive sands form the ‘core’ of the deep-water deposits in proximal and medial locations, but DWMS sensu stricto are primarily located in the distal locations of a basin; (5) graded and ungraded massive sands are laterally extensive, but those exhibiting ‘patchy’ texture are spatially restricted; and (6) massive sand facies associations are characterised by low heterogeneity, but distinct layering can be defined using petrophysical properties that are not observed at the macroscopic scale. Based on these findings, new models of DWMS deposition are presented for graded and ungraded massive sands, and massive sands with ‘patchy’ texture. These new modes of deposition for DWMS control grain- to element-scale heterogeneity in the sedimentological characteristics, which in turn controls petrophysical trends at different scales and ultimately affect how hydrocarbons hosted in massive sands are produced

Efficiency Analysis of Competing Tests for Finding Differentially Expressed Genes in Lung Adenocarcinoma

In this study, we introduce and use Efficiency Analysis to compare differences in the apparent internal and external consistency of competing normalization methods and tests for identifying differentially expressed genes. Using publicly available data, two lung adenocarcinoma datasets were analyzed using caGEDA (http://bioinformatics2.pitt.edu/GE2/GEDA.html) to measure the degree of differential expression of genes existing between two populations. The datasets were randomly split into at least two subsets, each analyzed for differentially expressed genes between the two sample groups, and the gene lists compared for overlapping genes. Efficiency Analysis is an intuitive method that compares the differences in the percentage of overlap of genes from two or more data subsets, found by the same test over a range of testing methods. Tests that yield consistent gene lists across independently analyzed splits are preferred to those that yield less consistent inferences. For example, a method that exhibits 50% overlap in the 100 top genes from two studies should be preferred to a method that exhibits 5% overlap in the top 100 genes. The same procedure was performed using all available normalization and transformation methods that are available through caGEDA. The ‘best’ test was then further evaluated using internal cross-validation to estimate generalizable sample classification errors using a Naïve Bayes classification algorithm. A novel test, termed D1 (a derivative of the J5 test) was found to be the most consistent, and to exhibit the lowest overall classification error, and highest sensitivity and specificity. The D1 test relaxes the assumption that few genes are differentially expressed. Efficiency Analysis can be misleading if the tests exhibit a bias in any particular dimension (e.g. expression intensity); we therefore explored intensity-scaled and segmented J5 tests using data in which all genes are scaled to share the same intensity distribution range. Efficiency Analysis correctly predicted the ‘best’ test and normalization method using the Beer dataset and also performed well with the Bhattacharjee dataset based on both efficiency and classification accuracy criteria

Tests for finding complex patterns of differential expression in cancers: towards individualized medicine

BACKGROUND: Microarray studies in cancer compare expression levels between two or more sample groups on thousands of genes. Data analysis follows a population-level approach (e.g., comparison of sample means) to identify differentially expressed genes. This leads to the discovery of 'population-level' markers, i.e., genes with the expression patterns A > B and B > A. We introduce the PPST test that identifies genes where a significantly large subset of cases exhibit expression values beyond upper and lower thresholds observed in the control samples. RESULTS: Interestingly, the test identifies A > B and B < A pattern genes that are missed by population-level approaches, such as the t-test, and many genes that exhibit both significant overexpression and significant underexpression in statistically significantly large subsets of cancer patients (ABA pattern genes). These patterns tend to show distributions that are unique to individual genes, and are aptly visualized in a 'gene expression pattern grid'. The low degree of among-gene correlations in these genes suggests unique underlying genomic pathologies and high degree of unique tumor-specific differential expression. We compare the PPST and the ABA test to the parametric and non-parametric t-test by analyzing two independently published data sets from studies of progression in astrocytoma. CONCLUSIONS: The PPST test resulted findings similar to the nonparametric t-test with higher self-consistency. These tests and the gene expression pattern grid may be useful for the identification of therapeutic targets and diagnostic or prognostic markers that are present only in subsets of cancer patients, and provide a more complete portrait of differential expression in cancer

A REVIEW OF ANALYTICAL TECHNIQUES FOR DETERMINATION OF ANTI-HIV DRUGS

Pharmaceutical analysis plays a very prominent role in quality assurance as well as quality control of bulk drugs and pharmaceutical formulations. Rapid increase in pharmaceutical industries and production of drug in various parts of the world has brought a rise in demand for new analytical techniques in the pharmaceutical industries. As a consequence, analytical method development has become the basic activity of analysis. From the times of yore, people were trying to find safe and sound ways to treat viral infections. In the current scenario, due to the emerging of new viruses, the development of drugs for their treatment is also gaining equal importance. Before launching to the market, these drugs should undergo a validation process. High-performance liquid chromatography (HPLC) coupled with ultraviolet (UV), Photodiode array detectors (PDA), Mass spectrophotometer (MS) detectors etc. is one of the fastest, safe and precise technologies used for determination and separation of pharmaceutical drugs, impurities and biological samples. HPLC is versatile and it takes less time for quantification of drugs as compared to old liquid chromatography techniques. Tenofovir disoproxil fumarate (TDF), Emtricitabine (FTC) and Efavirenz (EFV) is antiretroviral medicine used treat AIDS as well as chronic Hepatitis-B. It is used alone or with other&nbsp;HIV&nbsp;medications to help control&nbsp;HIV&nbsp;infection. The present review article assesses the published analytical methods and a variety of approach for investigation of TDF, FTC and EFV in bulk drug as well as pharmaceutical formulations including combinations. The present studies revealed that HPLC technique along with the spectroscopic have been most widely explored for the analysis. The investigatory review may provide the comprehensive details to the researchers who are working in the area of analytical research of TDF, FTC and EFV

Preparation and characterization of 5-fu loaded microspheres of eudragit and ethylcellulose

En la presente investigación, se han preparado microesferas de Eudragit (RS 100, RL 100 y RSPO) y etilcelulosa cargadas con 5-fluorouracilo. Se ha utilizado la técnica de “evaporación del disolvente o/o” para preparar las microesferas utilizando el sistema de (metanol + acetona)/ parafina líquida. Se ha utilizado estearato de magnesio como estabilizador de gotículas y se ha añadido n-hexano para endurecer las microesferas. Las microesferas preparadas se caracterizan por sus propiedades micromeríticas y su eficaz compresión, así como a través de la espectroscopia infrarroja transformada de Fourier (FTIR, por sus siglas en inglés) y la cromatografía en capa fina. Se han tomado microfotografías para estudiar la forma de las microesferas. La mejor cinética de liberación se ha alcanzado con el modelo de Higuchi. El tamaño de la partícula principal, la eficacia de compresión y los rendimientos de producción han sido fuertemente influenciados por el tipo de polímero y su concentración. Tras la presente investigación, se ha determinado que el Eudragit y la Etilcelulosa tienen carreras muy prometedoras en la liberación controlada para el 5-FUIn the present investigation, 5-fluorouracil loaded microspheres of Eudragit (RS 100, RL 100 and RSPO) and ethylcellulose were prepared. “O/O solvent evaporation” technique was used for preparation of microspheres using (methanol + acetone)/liquid paraffin system. Magnesium stearate was used as the droplet stabilizer and n-hexane was added to harden the microspheres. The prepared microspheres were characterized for their micromeretic properties and entrapment efficiency; as well by Fourier transform infrared spectroscopy (FTIR) and thin layer chromatography (TLC). Photomicrographs were taken to study the shape of microspheres. The best fit release kinetics was achieved with Higuchi plot. Mean particle size, entrapment efficiency and production yields were highly influenced by the type of polymer and polymer concentration. It is concluded from the present investigation that various Eudragit and Ethylcellulose are promising controlled release carriers for 5-FU