A Review-Botnet Detection and Suppression in Clouds

Internet security problems remain a major challenge with many security concerns such as Internet worms, spam, and phishing attacks. Botnets is well-organized distributed network attacks, consist of a large number of bots that generate huge volumes of spam or launch Distributed Denial of Service (DDoS) attacks on victim hosts. Botnet attacks degrade the status of Internet security. Clouds provide botmaster with an ideal environment of rich computing resources where it can easily deploy or remove C&C server and perform attacks.  It is of vital importance for cloud service providers to detect botnet,  prevent attack,  and trace back to the botmaster.  It also becomes necessary to detect and suppress these bots to protect the clouds. This paper provides the various botnet detection techniques and the comparison of various botnet detection techniques. It also provides the botnet suppression technique in cloud. Keywords: Cloud computing, network security, botnet, botmmaster, botnet detection, botnet suppressio

Space platform power system hardware testbed

The scope of the work on the NASA Space Platform includes the design of a multi-module, multi-phase boost regulator, and a voltage-fed, push-pull autotransformer converter for the battery discharger. A buck converter was designed for the charge regulator. Also included is the associated mode control electronics for the charger and discharger, as well as continued development of a comprehensive modeling and simulation tool for the system. The design of the multi-module boost converter is discussed for use as a battery discharger. An alternative battery discharger design is discussed using a voltage-fed, push-pull autotransformer converter. The design of the charge regulator is explained using a simple buck converter. The design of the mode controller and effects of locating the bus filter capacitor bank 20 feet away from the power ORU are discussed. A brief discussion of some alternative topologies for battery charging and discharging is included. The power system modeling is described

Study of Sun Position Tracking Method Based On Path of Sun Using Combine Linear And Rotary Motion Mechanism

Present paper shows the effective utilization of solar energy. Solar energy can be converted into electricity by using PV cell. The efficiency off PV Cells lowers in fixed tilt solar panel. And its efficiency depends on direction off sun rays. to recover the efficiency dual axis sun tracking system use, But disadvantage of this system is, it requires solar mapping which increases cost of system. Also this system I s very bulky, require more space and cannot transfer from one place to another. It can be used in a area where solar mapping is done. And less effective in other area. The proposed sun position tracking mechanism works faster and tracks the position of sun in less time and increases the output from solar panel

Effect of Nanofluid on Cooling System of Engine

An automobile radiator is used for the cooling purpose of the engine. The cooling system of an engine plays an important role in its performance for these reason researchers are using different types of Nano fluids as coolant which increases the effectiveness of radiator, increases the performance of an engine and decline the fuel consumption. In this study 1.2% volume concentration of Al2O3 nano particles water based nano fluid is used and observes that effectiveness of an automobile radiator enhance up to 23% at constant mass flow rate

Machine Learning in Automated Text Categorization

The automated categorization (or classification) of texts into predefined categories has witnessed a booming interest in the last ten years, due to the increased availability of documents in digital form and the ensuing need to organize them. In the research community the dominant approach to this problem is based on machine learning techniques: a general inductive process automatically builds a classifier by learning, from a set of preclassified documents, the characteristics of the categories. The advantages of this approach over the knowledge engineering approach (consisting in the manual definition of a classifier by domain experts) are a very good effectiveness, considerable savings in terms of expert manpower, and straightforward portability to different domains. This survey discusses the main approaches to text categorization that fall within the machine learning paradigm. We will discuss in detail issues pertaining to three different problems, namely document representation, classifier construction, and classifier evaluation.Comment: Accepted for publication on ACM Computing Survey

Using phage Lytic Enzymes to Control Pathogenic Bacteria

Our laboratory has developed phage lytic enzymes to prevent infection by specifically destroying disease bacteria on mucous membranes and in blood. Enzymes specific for S. pneumoniae and S. pyogenes have been developed to be used nasally and orally to control these organisms in environments such as hospitals and nursing homes to prevent or markedly reduce serious infections by these pathogens. In addition, a B. anthracis-specific enzyme was developed to kill the vegetative forms of these bacteria in the blood of infected individuals. In animal studies, >80% of mice colonized mucosally or infected intravenously with pathogenic bacteria were decolonized or survived after a single enzyme treatment delivered to the same site of colonization or infection

New physical characterization of the Fontana Lapilli basaltic Plinian eruption, Nicaragua

The Fontana Lapilli deposit was erupted in the late Pleistocene from a vent, or multiple vents, located near Masaya volcano (Nicaragua) and is the product of one of the largest basaltic Plinian eruptions studied so far. This eruption evolved from an initial sequence of fluctuating fountain-like events and moderately explosive pulses to a sustained Plinian episode depositing fall beds of highly vesicular basaltic-andesite scoria (SiO2 > 53 wt%). Samples show unimodal grain size distribution and a moderate sorting that are uniform in time. The juvenile component predominates (> 96 wt%) and consists of vesicular clasts with both sub-angular and fluidal, elongated shapes. We obtain a maximum plume height of 32 km and an associated mass eruption rate of 1.4 × 108 kg s−1 for the Plinian phase. Estimates of erupted volume are strongly sensitive to the technique used for the calculation and to the distribution of field data. Our best estimate for the erupted volume of the majority of the climactic Plinian phase is between 2.9 and 3.8 km3 and was obtained by applying a power-law fitting technique with different integration limits. The estimated eruption duration varies between 4 and 6 h. Marine-core data confirm that the tephra thinning is better fitted by a power-law than by an exponential trend

Exosomes Derived from M. Bovis BCG Infected Macrophages Activate Antigen-Specific CD4+ and CD8+ T Cells In Vitro and In Vivo

Activation of both CD4+ and CD8+ T cells is required for an effective immune response to an M. tuberculosis infection. However, infected macrophages are poor antigen presenting cells and may be spatially separated from recruited T cells, thus limiting antigen presentation within a granuloma. Our previous studies showed that infected macrophages release from cells small membrane-bound vesicles called exosomes which contain mycobacterial lipid components and showed that these exosomes could stimulate a pro-inflammatory response in naïve macrophages. In the present study we demonstrate that exosomes stimulate both CD4+ and CD8+ splenic T cells isolated from mycobacteria-sensitized mice. Although the exosomes contain MHC I and II as well as costimulatory molecules, maximum stimulation of T cells required prior incubation of exosomes with antigen presenting cells. Exosomes isolated from M. bovis and M. tuberculosis infected macrophages also stimulated activation and maturation of mouse bone marrow-derived dendritic cells. Interestingly, intranasal administration of mice with exosomes isolated from M. bovis BCG infected macrophages induce the generation of memory CD4+ and CD8+ T cells. The isolated T cells also produced IFN-γ upon restimulation with BCG antigens. The release of exosomes from infected macrophages may overcome some of the defects in antigen presentation associated with mycobacterial infections and we suggest that exosomes may be a promising M. tuberculosis vaccine candidate