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Search Results: 1 - 10 of 22377 matches for " Gangolu Vijay Kumar "
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Finite Element Analysis and Vibration Control of a Deep Composite Cylindrical Shell Using MFC Actuators
Gangolu Vijay Kumar,Samikkannu Raja,Karavadappa Basavarajappa Prasanna,Valliappan Sudha
Smart Materials Research , 2012, DOI: 10.1155/2012/513271
Abstract: A four-node composite facet-shell element is developed, accounting for electromechanical coupling of Macrofiber Composite (MFC) and conventional PZT patches. Further a warping correction is included in order to capture correctly the induced strain of conformable MFC, surface bonded on a cylindrical shell. The element performance to model the relations between in-plane electric field to normal strains is examined with the help of experiment and ANSYS analysis. In ANSYS, a simple modeling scheme is proposed for MFC using a parallel capacitors concept. The independent modal space control technique has been revisited to address the control of combination resonances through a selective modal space control scheme, where two or more modes can be combined to form the vibrating system or plant in modal domain. The developed control schemes are implemented in a digital processor using DS1104 and the closed-loop vibration control experiments are conducted on a CFRP shell structure. The influence of directionally induced actuation of MFC actuators on elastic couplings of composite shell is studied theoretically and is subsequently demonstrated in experiments. MFC actuators provide the much needed optimization domain for achieving the vibration control of combination resonances of elastically coupled deep-shell structure. 1. Introduction Active control techniques are becoming more popular in recent years due to the emergence of a field called “Smart Materials and Structure.” Smart materials such as piezoelectric, shape memory alloys, and magnetostrictive have got multi functional behaviors, namely, actuation, sensing, and load carrying. Among these, the electromechanically coupled piezoelectric materials possess immense potentials because of its dynamic characteristics (wider frequency band, large force) and their availability in different forms (bar, patch, composite, stack, etc.). Piezoelectric patches and composites such as Macrofibre Composite (MFC), Active Fibre Composite (AFC) are increasingly considered as actuators by research communities to address various vibration control-related problems in recent years [1–7]. Shell structures are commonly adopted in aerospace vehicles [8]. The wing panels, fuselage outer skins, tail panels, and so forth are constructed with shell structural elements using aluminum and composite materials. Light weight aerospace, naval and civil engineering structures usually employ shell configurations to attain structural efficiencies such as improved stiffness, desired shape, optimal weight, and aeroelastic characteristics. Although
Enhancement of Elastic Modulus of Epoxy Resin with Carbon Nanotubes  [PDF]
Vijay Kumar Srivastava
World Journal of Nano Science and Engineering (WJNSE) , 2011, DOI: 10.4236/wjnse.2011.11001
Abstract: Nanocomposites consisting of multiwall carbon nanotubes (MWCNT) and epoxy resin were produced by a standard calendaring technique. In this study, 3% multiwall carbon nanotube particles were dispersed in epoxy resin by weight to produce the multiwall carbon nanotubes/epoxy composite. Nanohardness and Raman spectroscopy tests were used to obtain the modulus of elasticity and Raman intensity of MWCNTs/ epoxy resin composite. The results show that the Raman intensity increased with the increase of Raman shift and Raman intensity also affected with the reinforcement of multiwall carbon nanotubes and 1% exposure of laser power. Also, nanohardness increased with increase of modulus of elasticity, which indicated that the toughness of epoxy resin improved with the addition of multiwall carbon nanotubes.
On the Artificial Equilibrium Points in a Generalized Restricted Problem of Three Bodies  [PDF]
Kumari Ranjana, Vijay Kumar
International Journal of Astronomy and Astrophysics (IJAA) , 2013, DOI: 10.4236/ijaa.2013.34059
Abstract:

The present article studies the stability conditions of central control artificial equilibrium generalized restricted problem of three bodies. It is generalized in the sense that here we have taken the larger primary body to be in shape of an oblate spheroid. The equilibrium points are sought by the application of the propellant for which it would just balance the gravitational forces. The launching flight of such a satellite is seen to be applicable for having arbitrary space stations for these different missions. Specialty of the result of the investigation lies in the fact that an arbitrary space station can be formed to attain any specified mission.

On the Artificial Equilibrium Points in the Circular Restricted Problem of 2 + 2 Bodies  [PDF]
Kumari Ranjana, Vijay Kumar
International Journal of Astronomy and Astrophysics (IJAA) , 2017, DOI: 10.4236/ijaa.2017.74020
Abstract: The present work studies the stability condition of central control artificial equilibrium points of the planar circular restricted problem of 2 + 2 bodies (PCRP2 + 2B) and also its variant when the shape of larger mass is taken to be an oblate spheroid. We find that the paper will be of great application in choosing an artificial equilibrium point (AEP) in the neighbourhood of numerous planets e.g. Jupiter or the bodies which provide a model of the problem studied. The minimum thrust will save a quantum of energy to be applied to have an arbitrary point as a chosen starter. For solar sailing and magnetic force this minimum thrust will be of great use.
An O(k2+kh2+h2) Accurate Two-level Implicit Cubic Spline Method for One Space Dimensional Quasi-linear Parabolic Equations  [PDF]
Ranjan Kumar Mohanty, Vijay Dahiya
American Journal of Computational Mathematics (AJCM) , 2011, DOI: 10.4236/ajcm.2011.11002
Abstract: In this piece of work, using three spatial grid points, we discuss a new two-level implicit cubic spline method of O(k2 + kh2 + h4) for the solution of quasi-linear parabolic equation , 0< x <1, t > 0 subject to appropriate initial and Dirichlet boundary conditions, where h > 0, k > 0 are grid sizes in space and time-directions, respectively. The cubic spline approximation produces at each time level a spline function which may be used to obtain the solution at any point in the range of the space variable. The proposed cubic spline method is applicable to parabolic equations having singularity. The stability analysis for diffusion- convection equation shows the unconditionally stable character of the cubic spline method. The numerical tests are performed and comparative results are provided to illustrate the usefulness of the proposed method.
ERβ interacting protein ERAP 140 shows age dependent alteration in its interaction and expression in male mouse brain  [PDF]
Vijay Paramanik, Mahendra Kumar Thakur
World Journal of Neuroscience (WJNS) , 2013, DOI: 10.4236/wjns.2013.31001
Abstract:

Estrogen mediates multiple functions in the brain through the interaction of estrogen receptor (ER)α and ERβ with a host of nuclear proteins that regulate specific gene transcription. We have identified ERAP 140, AIB 1, Trk A, Src, pCREB and CREB as ERβ interacting proteins in the mouse brain. Earlier we showed that the interaction of ERβ with ERAP 140 decreased whereas its expression increased with aging in the brain of female mice. Here we report that the pattern of interaction and expression is different in male mice as compared to females. The interaction of ERAP 140 with ERβ decreased in adult male mouse brain as compared to young and remained almost similar in old whereas its expression was higher in adult than young and old, which were almost similar. Further in silico secondary structure analysis by self-optimized prediction method alignment (SOPMA) and PSIPRED revealed that ERβ interacting proteins were rich in alpha helices and coils. Such findings might help to design ER modulators which can regulate specific functions of estrogen in the brain during aging and degenerative diseases.

Outbreak Investigation of Cholera in a Slum of Northern India  [PDF]
Manoj Kumar, Vijay Lakshmi Sharma
Open Journal of Epidemiology (OJEpi) , 2014, DOI: 10.4236/ojepi.2014.44031
Abstract: Cholera is one of the oldest and best understood endemic diseases. An actual bacterial enteric disease, it is characterized in its severe form by sudden onset, profuse painless watery stools (rice-water stool), nausea and profuse vomiting early in the course of illness. Endemic and pandemics are strongly linked to the consumption of unsafe water, poor hygiene, poor sanitation and crowded living conditions. A rapid survey was conducted for the outbreak investigation on August 4, 2008. The objectives were to investigate the outbreak, risk factors for cholera and recommend control measures immediately. Questionnaire based random convenient sample based investigative study. 60 families were contacted by the public health students. Approximate 300 individuals were screened for cholera cases. Simultaneously six water samples were also collected from the contacted family. Microbiological test for Vibrio cholera and E. coli was conducted. Randomly six water samples were collected from the Rajive colony. Microbiological test for Vibrio cholera and E. coli was conducted from the department of Microbiology, PU. Vibrio cholera and E. coli were found absent, in all the samples. One sample was found positive for unidentified bacteria.
Hepatitis B virus DNA integration and transactivation of cellular genes
Vijay Kumar
Iatreia , 2007,
Abstract: Chronic hepatitis B virus (HBV) infection is etiologically related to human hepatocellular carcinoma (HCC). Most HCCs contain integrated HBV DNA in hepatocyte, suggesting that the integration may be involved in carcinogenesis. Available data on the integrants from human hepatocellular carcinomas seem to represent primary integrants as well as the products of secondary rearrangements. By means of structural analyses of the possible primary integrants, it has been observed that the replication intermediates of the viral genome are the preferred substrates for integration. The integrated HBV DNA and the target cellular DNA are invariably associated with deletions, possibly reflecting the substrate for, and the mechanism of, the integration reaction. The host DNA sequences as well as the target site of integration in chromosomes are selected randomly suggesting that HBV DNA integration should bring about random mutagenic effects. Analysis of the samples recovered from hepatocellular carcinomas show that the integrated HBV DNA can mediate secondary rearrangements of chromosomes, such as translocations, inversions, deletions and (possibly) amplifications. The integration of HBV DNA into the host genome occurs at early steps of clonal tumor expansion. The integration has been shown in a number of cases to affect a variety of cancer-related genes and to exert insertional mutagenesis. However, in contrast to the woodchuck model, in which specific HBV-DNA integration is detectable in most cases, insertional activation or inactivation of cellular genes appears to be a rare event in man. The discovery of transactivating functions exerted by HBx and truncated HBs(urface) proteins supports the notion that these could be relevant to hepatocarcinogenesis as these transactivator sequences have been found in a large number of HCC tumors or hepatoma-derived cell lines. The HBx transactivator can stimulate a wide range of cellular genes and displays oncogenic potential in cell culture as well as in a transgenic environment. The HBs transactivators are encoded by the preS/S region of S gene and may involve carboxy terminal truncation to gain transactivation function. Expression of host genes by viral transactivators is mediated by regulatory elements of the cellular transcription factors like c-fos, c-myc, NF-kappa B, SRE and Sp1. Thus, during hepatitis B infection, the tendency of rearrangement of hepatocyte chromosomes is combined with the forcible turnover of cells. This is a constantly operating system for the selection of cells that grow better than normal cells, possib
Cell cycle deregulation by the HBx protein of hepatitis B virus
Vijay Kumar
Iatreia , 2007,
Abstract: Cell cycle control by oncogenic viruses usually involves disruption of the normal restraints on cellular proliferation via abnormal proteolytic degradation and malignant transformation of cells. The cell cycle regulatory molecules viz. cyclins, cyclin-dependent kinases (cdks) and inhibitors of cdks as well as the transcriptional targets of signaling pathways induce cells to move through the cell cycle checkpoints. These check points are often found deregulated in tumor cells and in the cells afflicted with DNA tumor viruses predisposing them towards transformation. The X protein or HBx of hepatitis B virus is a promiscuous transactivator that has been implicated in the development of hepatocellular carcinoma in humans. However, the exact role of HBx in establishing a permissive environment for hepatocarcinogenesis is not fully understood. HBx activates the Ras-Raf-MAP kinase signaling cascade, through which it activates transcription factors AP-1 and NFkappa B, and stimulates cell DNA synthesis. HBx shows a profound effect on cell cycle progression even in the absence of serum. It can override the replicative senescence of cells in G0 phase by binding to p55sen. It stimulates the G0 cells to transit through G1 phase by activating Src kinases and the cyclin A-cyclin-dependent kinase 2 complexes, that in turn induces the cyclin A promoter. There is an early and sustained level of cyclin-cdk2 complex in the presence of HBx during the cell cycle which is coupled with an increased protein kinase activity of cdk2 suggesting an early appearance of S phase. The interaction between cyclin-cdk2 complex and HBx occurs through its carboxyterminal region (amino acids 85-119) and requires a constitutive Src kinase activity. The increased cdk2 activity is associated with stabilization of cyclin E as well as proteasomal degradation of cdk inhibitor p27Kip1. Notably, the HBx mutant that fails to interact with cyclin-cdk2 complex, also fails to destabilize p27Kip1 or deregulate cell cycle. Thus, HBx appears to override normal cell cycle restraints by directly interacting with the key cell cycle regulators and modu lating their activities. These data suggest a molecular mechanism by which HBx likely contributes to viral carcinogenesis. Driving the HBV-infected cells to grow continuously may be essential for active viral replication that could facilitate the full manifestation of the oncogenic potential of HBx. BIBLIOGRAFíA 1. Benn J, Schneider RJ. (1995) Hepatitis B virus HBx protein deregulates cell cycle checkpoint controls. Proc Natl Acad Sci USA 92, 11215-11219. 2. B
Traffic and Transportation Problems of Metro Cities: Case of Meerut, Uttar Pradesh
Vijay kumar
American Journal of Engineering Research , 2013,
Abstract: Metro cities in India are facing acute traffic and transportation problems leading to deteriorated quality of life and weak socio-- economic structure. The problems range from inefficiency of roads and transport infrastructure to deal with exorbitantly increasing in magnitude of vehicles especially the personal ones , lack of mass transportation systems , encroachments on roads ,lack of pedestrian facilities and weak traffic management systems. This paper focuses these problems contextual to Meerut city, one of the priority town of NCR. The probable solution to this gigantic problem can be creation of an independent, ―Traffic and Transportation Authorities‖ at city level which should be technically strong in equipments, technology, and trained manpower & experts. Beside this comprehensive traffic and transportation plan should be made mandatory for all cities along with efficient management strict enforcement.
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