BH-centroids: A New Efficient Clustering Algorithm

The k-means algorithm is one of most widely used method for discovering clusters in data; however one of the main disadvantages to k-means is the fact that you must specify the number of clusters as an input to the algorithm. In this paper we present an improved algorithm for discovering clusters in data by first determining the number of clusters k, allocate the initial centroids, and then clustering data points by assign each data point to one centroid. We use the idea of Gravity, by assuming each data point in the cluster has a gravity that attract the other closest points, this leads each point to move toward the nearest higher gravity toward the nearest higher gravity point to have at the end one point for each cluster, which represent the centroid of that cluster. The measure of gravity of point (X) determined by its weight, which represent the number of points that use point X as the nearest point. Our algorithm employ a distance metric based (eg, Euclidean) similarity measure in order to determine the nearest or the similar point for each point. We conduct an experimental study with real-world as well as synthetic data sets to demonstrate the effectiveness of our techniques

Angular Momentum Partitioning and Hexacontatetrapole Moments in Impulsively Excited Argon Ions

We have studied polarized electron collisions with Ar in which the target is simultaneously ionized and excited to form Ar+(3p4(1D)4p) states. We measured the integrated Stokes parameters of the subsequent fluorescence emitted by the 2F7/2, 2F5/2, 2D5/2, and 2P3/2 states along the direction of electron polarization. The Rubin-Bederson hypothesis is shown to hold for the L and S multipoles of these states. The electric quadrupole and hexadecapole of the 1D core are derived. By recoupling these moments with the electric quadrupole moment of the 4p electron, we calculate higher moments of the total ionic orbital angular momentum, including its hexacontatetrapole (64-pole) moment

Angular momentum partitioning and the subshell multipole moments in impulsively excited argon ions

We have investigated collisions between transversely polarized electrons and Ar, in which the Ar is simultaneously ionized and excited to the Ar+*[3p4(+D)4p] states. The Stokes parameters of the fluorescence emitted in the following transitions was measured: (+D)4s 2D/2−(1D)4p 2F7/2 (461.0 nm), (1D)4s 2D5/2 −(1D)4p 2F5/2 (463.7 nm), (1P)3d 2D5/2−(1D)4p 2D5/2 (448.2 nm), and (1D)4s 2D3/2−(1D)4p 2P3/2 (423.7 nm). We develop the angular momentum algebra necessary to extract from these data, starting from the overall atomic J multipoles, the partitioning of orbital angular momentum into the 1D core electric quadrupole and hexadecapole moments, and the outer 4p electric quadrupole moment. The magnetic dipole of the outer electron is also determined. This procedure requires the assumption of good LS coupling for these states, which is justified. We recouple these individual core- and outer-electron moments to calculate the initial electric quadrupoles, hexadecapoles, and hexacontatetrapoles of the initial excited-state manifold. The detailed time structure of the electron-atom collision is considered, as well as the time evolution of the excited ionic state. The Rubin-Bederson hypothesis is thus shown to hold for the initial ionic L and S terms. The consequences of the breakdown of LS coupling are considered. From the circular polarization data, estimates of the relative importance of direct and exchange excitation cross section are made. We discuss experimental issues related to background contributions, Hanle depolarization of the fluorescence signal, and cascade contributions. Nonlinearity of the equations relating the Stokes parameters to the subshell multipole moments complicates the data analysis. Details of the Monte Carlo terrain-search algorithm used to extract multipole data is discussed, and the implications of correlation between the various subshell multipole moments is analyzed. The physical significance of the higher-order multipole moments is discussed, and graphical representations of the effects of these multipoles on the excited ionic charge clouds is presented

Cyclopentadienyl iron dicarbonyl styrene chalcogenosulfonates: synthesis and structure of CpFe(CO)(2)SeSO2CH=CHPh

In this contribution, we report the preparation of iron thiosulfonato complex CpFe(CO)(2)SSO2CH=CHPh (1) and its selenosulfonato analogue CpFe(CO)(2)SeSO2CH=CHPh (2) featuring styrene moiety. 1 and 2 are obtained by electrophilic attack of (mu-E-x)CpFe(CO)(2)](2) (E = S; x = 2-4, E = Se; x = 1) on the sulfur atom of styrene sulfonyl chloride ClSO2CH=CHPh. The new compounds, 1 and 2 have been characterized by elemental analyses, IR, H-1-, C-13{H-1}-NMR, UV-Vis spectroscopy and the structure of 2 is determined by X-ray crystallography

Exploring Deviant Hacker Networks (DHM) on Social Media Platforms

Online Social Networks (OSNs) have grown exponentially over the past decade. The initial use of social media for benign purposes (e.g., to socialize with friends, browse pictures and photographs, and communicate with family members overseas) has now transitioned to include malicious activities (e.g., cybercrime, cyberterrorism, and cyberwarfare). These nefarious uses of OSNs poses a significant threat to society, and thus requires research attention. In this exploratory work, we study activities of one deviant groups: hacker groups on social media, which we term Deviant Hacker Networks (DHN). We investigated the connection between different DHNs on Twitter: how they are connected, identified the powerful nodes, which nodes sourced information, and which nodes act as bridges between different network components. From this, we were able to identify and articulate specific examples of DHNs communicating with each other, with the goal of committing some form of deviant act online. In our work, we also attempted to bridge the gap between the empirical study of OSNs and cyber forensics, as the growth of OSNs is now bringing these two domains together, due to OSNs continuously generating vast amounts of evidentiary data

Preliminaries of orthogonal layered defence using functional and assurance controls in industrial control systems

Industrial Control Systems (ICSs) are responsible for the automation of different processes and the overall control of systems that include highly sensitive potential targets such as nuclear facilities, energy-distribution, water-supply, and mass-transit systems. Given the increased complexity and rapid evolvement of their threat landscape, and the fact that these systems form part of the Critical National infrastructure (CNI), makes them an emerging domain of conflict, terrorist attacks, and a playground for cyberexploitation. Existing layered-defence approaches are increasingly criticised for their inability to adequately protect against resourceful and persistent adversaries. It is therefore essential that emerging techniques, such as orthogonality, be combined with existing security strategies to leverage defence advantages against adaptive and often asymmetrical attack vectors. The concept of orthogonality is relatively new and unexplored in an ICS environment and consists of having assurance control as well as functional control at each layer. Our work seeks to partially articulate a framework where multiple functional and assurance controls are introduced at each layer of ICS architectural design to further enhance security while maintaining critical real-time transfer of command and control traffic

A Case of Chronic Cough and Pneumonia Secondary to a Foreign Body

Foreign body aspiration occurs when a solid or semisolid object becomes lodged in the larynx or trachea. It can be a life-threatening emergency, especially if it is large enough to occlude the airway. However, small aspirated objects may go unnoticed until symptoms occur. Therefore, it is frequently misdiagnosed. A high level of clinical suspicion, patient\u27s risk factors, and thorough history and physical examination are essential in making the diagnosis. It should be considered in cases where there is unresolved chronic cough with or without associated recurrent pneumonia especially in patients with risks for aspiration

Adsorption thermodynamics and prediction of phase equilibria for activated carbon synthesized from waste grease.

The research is conducted to evaluate the thermodynamic parameters of adsorption processes and to predict the phase equilibria for carbon produced from a mixture of waste grease and raw sulfur. Phenol and p-nitrophenol were used for adsorption isotherm at different concentrations and temperatures. Thermodynamic functions such as Gibbs function (∆G), enthalpy (∆H) and entropy (∆S) changes during adsorption were calculated. The melting point measurements of waste grease and raw sulfur mixtures were obtained for different ratios. The lever rule is used to represent a quantitative determination in the two-phase region of a phase diagram using a certain equation.The phenol adsorption was mostly an endothermic process while the p-nitrophenol adsorption was an endothermic process for all samples as indicated by positive values of the enthalpy. Generally the adsorption processes were spontaneous as pointed out by entropy and free energy values. Various phases and boundaries were occurred at three regions with 2-phase while 1-phase is exist in the system especially at high temperatures. The ratio of lliquid/lsolid was increased with reducing temperature and the amounts of liquid were reduce

The cellular senescence response and neuroinflammation in juvenile mice following controlled cortical impact and repetitive mild traumatic brain injury.

Traumatic brain injury (TBI) is a leading cause of disability and increases the risk of developing neurodegenerative diseases. The mechanisms linking TBI to neurodegeneration remain to be defined. It has been proposed that the induction of cellular senescence after injury could amplify neuroinflammation and induce long-term tissue changes. The induction of a senescence response post-injury in the immature brain has yet to be characterised. We carried out two types of brain injury in juvenile CD1 mice: invasive TBI using controlled cortical impact (CCI) and repetitive mild TBI (rmTBI) using weight drop injury. The analysis of senescence-related signals showed an increase in γH2AX-53BP1 nuclear foci, p53, p19ARF, and p16INK4a expression in the CCI group, 5 days post-injury (dpi). At 35 days, the difference was no longer statistically significant. Gene expression showed the activation of different senescence pathways in the ipsilateral and contralateral hemispheres in the injured mice. CCI-injured mice showed a neuroinflammatory early phase after injury (increased Iba1 and GFAP expression), which persisted for GFAP. After CCI, there was an increase at 5 days in p16INK4, whereas in rmTBI, a significant increase was seen at 35 dpi. Both injuries caused a decrease in p21 at 35 dpi. In rmTBI, other markers showed no significant change. The PCR array data predicted the activation of pathways connected to senescence after rmTBI. These results indicate the induction of a complex cellular senescence and glial reaction in the immature mouse brain, with clear differences between an invasive brain injury and a repetitive mild injury

EFFECT OF TOOL SHOULDER DIAMETER ON THE MECHANICAL PROPERTIES OF 1200 ALUMINUM FRICTION STIR SPOT WELDING

A friction stir spot welding (FSSW) process is an emerging solid state joining process in which the material that is being welded does not melt. In this investigation an attempt has been made to understand the effect of tool shoulder diameter on the mechanical properties of the joint. For this purpose four welding tools diameter (10,13, 16 and 19) mm at constant preheating time and plunging time were used to carry out welding process. Effect of tool diameter on mechanical properties of welded joints was investigated using shear stress test and Microhardness of joint which welded was studied. Based on the stir welding experiments conducted in this study the results show that aluminum alloy (1200) can be welded using (FSSW) process with maximum welding efficiency (80%) shear strength using tool diameter(19mm) with rotation speed (900rpm)