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Performance Analysis of View Maintenance Techniques for DW
S. Prakasha,R. Selvarani
Computer Science , 2010,
Abstract: A Data Warehouse stores integrated information as materialized views over data from one or more remote sources. These materialized views must be maintained in response to actual relation updates in the remote sources. The data warehouse view maintenance techniques are classified into four major categories self maintainable recomputation, not self maintainable recomputation, self maintainable incremental maintenance, and not self maintainable incremental maintenance. This paper provides a comprehensive comparison of the techniques in these four categories in terms of the data warehouse space usage and number of rows accessed in order to propagate an update from a remote data source to a target materialized view in the data warehouse.
Some Results on Generalized Quasi-Einstein Manifolds
D. G. Prakasha,H. Venkatesha
Chinese Journal of Mathematics , 2014, DOI: 10.1155/2014/563803
Abstract: This paper deals with generalized quasi-Einstein manifold satisfying certain conditions on conharmonic curvature tensor. Here we study some geometric properties of generalized quasi-Einstein manifold and obtain results which reveal the nature of its associated 1-forms. 1. Introduction It is well known that a Riemannian or a semi-Riemannian manifold ?? is an Einstein manifold if its Ricci tensor of type is of the form , being the (constant) scalar curvature of the manifold. Let . Then the manifold is said to be a quasi-Einstein manifold [1–7] if, on , we have where is -form on and , are some smooth functions on . It is clear that the function and the -form are nonzero at every point on . The scalars , are the associated scalars of the manifold. Also the 1-form is called associated 1-form of the manifold defined by for any vector field , being a unit vector field called generator of the manifold. Such an -dimensional quasi-Einstein manifold is denoted by . The quasi-Einstein manifolds have also been studied in [8–11]. Generalizing the notion of quasi-Einstein manifold, in [12], De and Ghosh introduced the notion of generalized quasi-Einstein manifolds and studied its geometrical properties with the existence of such notion by several nontrivial examples. A Riemannian manifold ?? is said to be generalized quasi-Einstein manifold if its Ricci tensor of type is not identically zero and satisfies the condition: where , , and?? are scalars of which , and , are nowhere vanishing 1-forms such that , for any vector field . The unit vectors and corresponding to 1-forms and are orthogonal to each other. Also and are the generators of the manifold. Such an -dimensional manifold is denoted by . The generalized quasi-Einstein manifolds have also been studied in [13–16]. In 2008, De and Gazi [17] introduced the notion of nearly quasi-Einstein manifolds. A nonflat Riemannian manifold ?? is called a nearly quasi-Einstein manifold if its Ricci tensor of type is not identically zero and satisfies the condition: where and are nonzero scalars and is a nonzero symmetric tensor of type . An -dimensional nearly quasi-Einstein manifold was denoted by . The nearly quasi-Einstein manifolds have also been studied by Prakasha and Bagewadi [18]. The present paper is organized as follows. Section 2 deals with the preliminaries. Section 3 is concerned with conharmonic curvature tensor on . In this section, it is proved that a conharmonically flat is one of the manifold of generalized quasiconstant curvature. Also, it is proved that if in a ?? the associated scalars are constants and
Identification of a human TFPI-2 splice variant that is upregulated in human tumor tissues
Prakasha Kempaiah, Hitendra S Chand, Walter Kisiel
Molecular Cancer , 2007, DOI: 10.1186/1476-4598-6-20
Abstract: Nucleotide sequence analyses indicated that asTFPI-2 consists of complete exons II and V, fused with several nucleotides derived from exons III and IV, as well as six nucleotides derived from intron C. 5'- and 3'-RACE analyses of total RNA amplified exclusively the wild-type TFPI-2 transcript, indicating that asTFPI-2 lacks either a 5'-untranslated region (UTR) or a 3'-poly (A)+ tail. Quantitative real-time RT-PCR analyses revealed that several human tumor cells contain 4 to 50-fold more copies of asTFPI-2 in comparison to normal cells. In spite of the absence of a 5'-UTR or poly (A)+ tail, the asTFPI-2 variant exhibited a half-life of ~16 h in tumor cells.Our studies reveal the existence of a novel, aberrantly-spliced TFPI-2 transcript predominantly expressed in tumor cells and provides suggestive evidence for an additional mechanism for tumor cells to down-regulate TFPI-2 protein expression enhancing their ability to degrade the extracellular matrix.Tissue factor pathway inhibitor-2 (TFPI-2) is a 32 kDa Kunitz-type serine proteinase inhibitor synthesized by a variety of cells and directionally secreted into their extracellular matrix (ECM) where it is thought to regulate plasmin-mediated ECM degradation and remodeling (reviewed by Chand et al. [1]). As matrix degradation is an important step in tumor invasion and metastasis, several, but not all, tumor cells downregulate TFPI-2 expression [2,3]. In this regard, overexpression of TFPI-2 in several tumor cells was shown to inhibit their growth, invasiveness, angiogenic potential and metastatic potential [4-9]. The mechanism whereby some tumor cells downregulate TFPI-2 synthesis has been primarily attributed to transcriptional silencing through hypermethylation of CpG sites in the TFPI-2 promoter [10-14], inasmuch as treatment of these tumor cells with a methyltransferase inhibitor, 5'-aza-2'-deoxycytidine, restored TFPI-2 transcription[14]. In addition, several highly aggressive tumors delete the locus for the TFPI-
FACEBOOK AS A SOCIALISING AGENT AND ITS IMPACT ON ACADEMIC ACHIEVEMENT OF AN INDIVIDUAL
PRAKASHA G.S,JACQUELINE BAREH
Golden Research Thoughts , 2013, DOI: 10.9780/22315063
Abstract: This article is aiming at creating awareness towards Face-book as a socializing agent and its impact on academic achievement of individuals pursuing education at various levels. Facebook a social networking site very widely used by teenagers and it has both positive and negative effects on an individual over his academic life as well as his or her social life. As parents, teachers and civilians it is very important to understand what goes on in there and what is its aftermath on an individual's life. This article makes its interpretation based on the research review and the data of few informal interviews the researcher had conducted. It concludes that Facebook certainly acts as a socialising agent, nevertheless affects academic- achievement of an individual.
Study of Reliable Data Communication in Wireless Sensor Networks
Purushotham BV,Prakasha S,K Ganesan
Lecture Notes in Engineering and Computer Science , 2008,
Abstract:
Characterization and Comparison of Corrosion Behavior of Nanostructured TiAlN and AlCrN Coatings on Superfer 800H (INCOLOY 800 H) Substrate  [PDF]
Vikas Chawla, D. Puri, S. Prakasha, Amita Chawla, Buta Singh Sidhu
Journal of Minerals and Materials Characterization and Engineering (JMMCE) , 2009, DOI: 10.4236/jmmce.2009.89062
Abstract: Nitrided coatings have been used to increase hardness and to improve the wear and corrosion resistance of structural materials. In this work, TiAlN and AlCrN coatings were deposited on Superfer 800H (INCOLOY 800 H) substrate by using Balzer’s rapid coating system (RCS) machine (make Oerlikon Balzers, Swiss) under a reactive nitrogen atmosphere. The coated samples were subjected to optical microscopy (OM), XRD analysis, Field emission scanning electron microscope (FESEM with EDAX attachment), AFM analysis. The corrosion resistance of the substrate, TiAlN-coated and AlCrN-coated samples in a 3 wt% NaCl solution was evaluated and compared by electrochemical potentiodynamic polarization method. It was found that the AlCrN-coating exhibited better corrosion resistance.
Seed Germination and Physiological Behavior of Maize (cv. Nac-6002) Seedlings under Abiotic Stress (Pendimethalin) Condition
N. Rajashekar,Prakasha,T.C. Shivashankara Murthy
Asian Journal of Crop Science , 2012,
Abstract: In the present investigation five treatments with pendimethalin concentrations namely 0.5, 1.0, 2.5, 5.0 and 10.0 ppm were given to maize cv. NAC-6002 grains to evaluate herbicidal toxicity on germination and early growth. The seedlings were maintained upto 15 days. Embryonic axis and endosperm of 4, 6, 8, 10 and 15 days old germinated soybean seedlings were used for bioassay on biochemical parameters viz., total protein, total carbohydrate, starch and reducing sugar were carried out. Germination percentage, length of radical and plumule were decreased significantly with increase in concentration of pendimethalin. The germinating seedlings of treated set showed high content of seed serves viz., total protein, total carbohydrate, starch and reducing sugar in the endosperms, whereas it was low in the shoot-root axis at all the days of observation over control. With increase in the days of germination the seed serves (protein, carbohydrate, starch and reducing sugar) showed a drastic decrease in control, whereas in treated sets the rate of seed reserves degradation was slow in the endosperm. On the contrary, in shoot-root axis a reverse trend was recorded in response to pendiemthalin treatment. The effect was more pronounced at higher herbicidal concentration. These results reveal that the mobilization of seed reserve was suppressed by pendimethalin, as result of impaired degradation of seed reserve, during germination and early growth.
Synthesis and Antimicrobial Activity of Amino Acids Conjugated Diphenylmethylpiperazine Derivatives
K. N. Shivakumara,K. C. Prakasha,D. Channe Gowda
Journal of Chemistry , 2009, DOI: 10.1155/2009/267296
Abstract:
On 3-Dimensional Contact Metric Generalized -Space Forms
D. G. Prakasha,Shyamal Kumar Hui,Kakasab Mirji
International Journal of Mathematics and Mathematical Sciences , 2014, DOI: 10.1155/2014/797162
Abstract: The present paper deals with a study of 3-dimensional contact metric generalized -space forms. We obtained necessary and sufficient condition for a 3-dimensional contact metric generalized -space form with to be of constant curvature. We also obtained some conditions of such space forms to be pseudosymmetric and -projectively flat, respectively. 1. Introduction In 1995, Blair et al. [1] introduced the notion of contact metric manifolds with characteristic vector field belonging to the -nullity distribution and such types of manifolds are called -contact metric manifolds. They obtained several results and examples of such a manifold. A full classification of this manifold has been given by Boeckx [2]. A contact metric manifold is said to be a generalized -space if its curvature tensor satisfies the condition for some smooth functions and on independent choice of vector fields and . If and are constant, the manifold is called a -space. If a -space has a constant -sectional curvature and a dimension greater than 3, the curvature tensor of this -space form is given by [3] where , , , , , and are the tensors defined by for all vector fields , , on , where and is the usual Lie derivative. The notion of generalized Sasakian-space-forms was introduced and studied by Alegre et al. [4] with several examples. A generalized Sasakian-space-form is an almost contact metric manifold whose curvature tensor is given by where , , and are the tensors defined above and , , are differentiable functions on . In such case we will write the manifold as . Generalized Sasakian-space-forms have been studied by several authors, namely, [5–11]. By motivating the works on generalized Sasakian-space-forms and -space forms, Carriazo et al. [12] introduced the concept of generalized -space forms. A generalized -space form is an almost contact metric manifold whose curvature tensor is given by where , , , , , are the tensors defined above and , , , , , are differentiable functions on . The object of the paper is to study 3-dimensional contact metric generalized -space forms. The paper is organized as follows. Section 2 deals with some preliminaries on contact metric manifolds and contact metric generalized -space forms. Section 3 is concerned with 3-dimensional contact metric generalized -space forms. Here it is proved that a 3-dimensional contact metric generalized -space form with is of constant curvature if and only if . In Section 4, it is proved that a 3-dimensional contact metric generalized -space form is Ricci-semisymmetric; then either or . In Sections 5 and 6, we obtained that
Three-Component One-Pot Synthesis of Novel Benzo[ ]1,8-naphthyridines Catalyzed by Bismuth(III) Chloride
Tangali R. Ravikumar Naik,Halehatty S. Bhojya Naik,Halehatty R. Prakasha Naik,P. J. Bindu
Organic Chemistry International , 2008, DOI: 10.1155/2008/594826
Abstract: A novel and efficient three-component one-pot synthesis of benzo[]1,8-naphthyridines by 2-amino-4-methylquinoline, aromatic aldehydes, and malononitrile was done. The reaction was catalyzed by an acidic Bismuth(III) chloride, functionalized Bismuth(III) chloride, at room temperature to give various benzo[]1,8-naphthyridines in high yields. The Bismuth(III) chloride is an environmentally friendly catalyst.
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