An Invariant Dual-beam Snowflake Antenna for Future 5G Communications

A broadband snowflake antenna for future 5G and millimeter-wave communications is presented. The proposed antenna has a size of 8 × 5 mm 2 . The antenna consists of a central hexagon surrounded by a series of symmetrically placed smaller hexagons around it, resulting in broadband characteristics. The impedance bandwidth of the proposed antenna ranges from 25.284-29.252 GHz. The antenna has a gain of 3.12 dBi at 28 GHz and is more than 98% efficient. A distinct feature of the proposed antenna is its dual-beam radiation pattern. The two beams remain fixed at ±50° even if the frequency is varied with in its operating band. The proposed antenna is modelled on thin Rogers substrate which makes it very useful for future 5G smart phones

Integration over matrix spaces with unique invariant measures

We present a method to calculate integrals over monomials of matrix elements with invariant measures in terms of Wick contractions. The method gives exact results for monomials of low order. For higher--order monomials, it leads to an error of order 1/N^alpha where N is the dimension of the matrix and where alpha is independent of the degree of the monomial. We give a lower bound on the integer alpha and show how alpha can be increased systematically. The method is particularly suited for symbolic computer calculation. Explicit results are given for O(N), U(N) and for the circular orthogonal ensemble.Comment: 12 pages in revtex, no figure

Coexisted Three-component Bosons and Two-component Weyl Bosons in TiS, ZrSe and HfTe

In analogy to various fermions of electrons in topological semimetals, topological mechanical states with two type of bosons, Dirac and Weyl bosons, were reported in some macroscopic systems of kHz frequency and those with a type of doubly-Weyl phonons in atomic vibrational framework of THz frequency of solid crystals were recently predicted. However, to date no three-component bosons of phonon has been reported. Here, through first-principles calculations, we have reported that the phonon spectra of the WC-type TiS, ZrSe, and HfTe commonly host the unique triply degenerate nodal points (TDNPs) and single two-component Weyl points (WPs) in THz frequency. Quasiparticle excitations near TDNPs of phonons are three-component bosons, beyond the conventional and known classifications of Dirac, Weyl and doubly-Weyl phonons. {Moreover, we have found that both TiS and ZrSe have five pairs of type-I Weyl phonons and a pair of type-II Weyl phonons, whereas HfTe only has four pairs of type-I Weyl phonons. They carry non-zero topological charges. On the (10$\bar{1}$0) crystal surfaces, we observe topological protected surface arc states connecting two WPs with opposite charges, which host modes that propagate nearly in one direction on the surface.Comment: 10 pages, 6 figures. arXiv admin note: substantial text overlap with arXiv:1706.0687

Anisotropic magnetotransport of superconducting and normal state in an electron-doped Nd_{1.85}Ce_{0.15}CuO_{4-\delta} single crystal

The anisotropic properties of an optimally doped Nd_{1.85}Ce_{0.15}CuO_{4-\delta} single crystal have been studied both below and above the critical temperature Tc via the resistivity measurement in magnetic field H up to 12 T. By scaling the conductivity fluctuation around the superconducting transition, the upper critical field H_{c2}(T) has been determined for field parallel to the c-axis or to the basal ab-plane. The anisotropy factor \gamma={H_c2||ab}/{H_c2||c} is estimated to be about 8. In the normal state (50=<T=<180 K), the magnetoresistance (MR) basically follows an H^2 dependence and for H||c it is almost 10 times larger than that for H||ab. Comparing with hole-doped cuprates it suggests that the optimally doped Nd_{1.85}Ce_{0.15}CuO_{4-\delta} cuprate superconductor has a moderate anisotropy.Comment: 5 pages, 4 figure

Lafora Disease Masquerading as Hepatic Dysfunction

Lafora disease is fatal intractable progressive myoclonic epilepsy. It is frequently characterized by epileptic seizures, difficulty walking, muscle spasms, and dementia in late childhood or adolescence. We chronicle here an unusual case of an asymptomatic young male soccer player who presented with elevated liver enzymes. Neurological examination was unremarkable. The diagnostic workup for hepatitis, infectious etiologies, autoimmune disorders, hemochromatosis, Wilson\u27s disease, alpha-1 antitrypsin deficiency, and other related diseases was inconclusive. He subsequently underwent an uneventful percutaneous liver biopsy. Based on the pathognomonic histopathological findings, Lafora disease was considered the likely etiology. The present study is a unique illustration of this rare disorder initially manifesting with abnormal liver enzymes. It underscores the importance of clinical suspicion of Lafora disease in cases with unexplained hepatic dysfunction. Prompt liver biopsy and genetic testing should be performed to antedate the onset of symptoms in these patients

Structural and electronic properties of oxygen defective and Se-doped p-type BiVO⁠4(001) thin film for the applications of photocatalysis

This is the final version. Available on open access from Elsevier via the DOI in this record.There is another record in ORE for this publication: http://hdl.handle.net/10871/36011Monoclinic BiVO4 is being used as a photocatalyst due to its stability, cost-effectiveness, ease of synthesis, and narrow band gap. Although, the valence band maximum, VBM (∼−6.80 eV vs vacuum) of BiVO4 is well below the redox potential of water but having less positive conduction band minimum, CBM (−4.56 eV vs vacuum), responsible for its low efficiency. We have carried out a comprehensive periodic density functional theory (DFT) simulations for the pristine, Oxygen defective (Ov) and Se doped BiVO4, to engineer not only its CB edge position but the overall photocatalytic and charge carrier properties. Our theoretical method has nicely reproduced the experimental data of pristine BiVO4, which encouraged us to elaborate further its Ov and Se-doped characteristics. It is found that both the Ov (1% Oxygen vacancy) and Se-doped BiVO4 (1–2% Se) have ideal band edges, band gaps, and small effective masses of electrons and holes, responsible for high photocatalytic activities. Moreover, Se-doped BiVO4 behave as p-type semiconductor. Finally, the photocatalytic water-splitting behaviour of the selected surfaces were counterchecked with water interaction, where the strong water adsorption energy of about ∼−38 to −50 kcal/mol, confirms and predicts their higher efficiencies compared to that of parent BiVO4.The financial support was provided by Engineering and Physical Science Research Council, UK (EPSRC) under the research grant No EP/P510956/1

Electric filed intensity of the lightning strikes on lightning air terminals installed on building structures

Lightning activities are growing up rapidly with global warming. It can affect anything on the earth. All the constructed buildings need proper protection from the harmful effect of lightning. Lightning strike points on different geometrical shapes have been investigated. Lightning strike distribution of different building structure is very important to be studied. In order to analyse the maximum effect of lightning strike pattern is obtained of different air terminals installed on scaled building structures. High voltage impulse generator is used in order to get the impulse voltage. Different numbers of air terminals have been applied to all the shapes in order to see the lightning strike points. Electric field is obtained in order to see its minimum and maximum effect on the entire building structure. Interestingly the phenomenon of lightning air terminal bypasses has been proved in this paper

Safety compliance for hihg rise projects in Nigerian construction Industry

Health and safety issues had always been a major challenge and concern in the construction industry. Construction is found to be one of the most dangerous on health and safety practice, predominantly in developing countries. As construction accidents continue to dominate the overall construction industry. Despite the programs implemented by government and measures introduced by companies the number of high rise construction accidents still remains alarmingly. This research aim to investigate the safety compliance for high rise construction project in Nigeria. In achieving this aim three (3) objectives has been outlined; to investigate the current level of compliance to safety practice and policies in Nigerian construction site. To investigate the factors that prevent the compliance to safety and health practices in high rise projects of Nigerian construction industry. To recommend appropriate ways to improve the compliance to safety in high rise of Nigerian construction. The interview and questionnaire method was used in this research. Structured Questionnaires was distributed to 108 potential respondents from the construction industry players 90 was returned and Qualitative interview have been conducted to meet the first objective of the project, to investigate the current level of compliance to safety practice In addition, structured interviews were carried out with selected managers from construction industry. The result shows that Bribery and corruption, Lack of training, Absence of safety representatives, Lack of corporate responsibility & Accountability, Weak legal structure were the significant factors affecting safety. Compliance. The result also indicate that Site inspection, Safety seminars (enforcement officers), Building codes of practice, Enforcement of safety act, Workers/labourers training are the effective factors that could improve compliance to safety practice in high rise project of Nigerian construction industry. It is recommended that relevant authorities should checkmate the Safety practices in the Nigerian construction industry