Adoption of Instant Messaging Technologies by University Students

The main objective of this paper is to better understand the nature and patterns of students’ socialization patterns in relation to the adoption of Instant Messaging (IM) systems. A model based on the Extended Planned Behavior Theory (EPBT) was applied to a sample of 80 students of software engineering at the University of New South Wales, Australia. Based on the EPBT model, a questionnaire was administered to these students. A number of key concepts were identified in relation to the students’ adoption of IM. It was also found that students use IM to support a number of task-related purposes such as collaborating with their classmates about group work and assignments, as well as for scheduling and coordinating meetings and significant results were obtained

Substantial and sustained reduction in under-5 mortality, diarrhea, and pneumonia in Oshikhandass, Pakistan : Evidence from two longitudinal cohort studies 15 years apart

Funding Information: Study 1 was funded through the Applied Diarrheal Disease Research Program at Harvard Institute for International Development with a grant from USAID (Project 936–5952, Cooperative Agreement # DPE-5952-A-00-5073-00), and the Aga Khan Health Service, Northern Areas and Chitral, Pakistan. Study 2 was funded by the Pakistan US S&T Cooperative Agreement between the Pakistan Higher Education Commission (HEC) (No.4–421/PAK-US/HEC/2010/955, grant to the Karakoram International University) and US National Academies of Science (Grant Number PGA-P211012 from NAS to the Fogarty International Center). The funding bodies had no role in the design of the study, data collection, analysis, interpretation, or writing of the manuscript. Publisher Copyright: © 2020 The Author(s).Peer reviewedPublisher PD

Theoretical investigations of spectroscopic, electronic and magnetic properties of new low dimensional systems

V této práci byly zkoumány důležité aspekty fotokatalytických materiálů, jako je Nb3O7 (OH) a Fe2O3, jako je elektronická struktura, zakázané pásmo, optoelektronické a spektroskopické vlastnosti. Účinky dopingových prvků v těchto materiálech byly rovněž zkoumány. Tyto vlastnosti byly vypočteny pomocí an ab initio kvantového mechanického přístupu. Vypočítaná mezera optického proužku a spektroskopické vlastnosti mají pěknou shodu s experimentálními daty. Byly vypočítány za použití funkční hustoty Becke-Johnson modifikované Tran-Blaha. U dopovaného Nb3O7 (OH) byly pozorovány malé, ale důležité změny v optoelektronických a spektroskopických vlastnostech, neboť dopingový prvek zvyšuje optickou absorpci. Zakázané pásmo bylo analyzováno a popsáno v Sn-Fe2O3. Úloha elektrického dipólového přechodu byla popsána poprvé v FeTiO3NeobhájenoThe important aspects of photocatalytic materials like Nb3O7(OH) and Fe2O3 were investigated in this thesis, like the electronic structure, band gap, optoelectronic and spectroscopic properties. The effects of the doping elements in these materials were also investigated. These properties were calculated using ab initio quantum mechanical approach. The calculated optical band gap and spectroscopic properties have nice agreement with the experimental data. These were calculated using the Tran-Blaha modified Becke-Johnson density functional. For doped Nb3O7(OH), a minor but important changes in the optoelectronic and spectroscopic properties was observed like an increase in the optical absorption was devoted to the doping element. Intermediate band were analyzed and described in Sn-Fe2O3. The role of electric dipole transition was described for the first time in FeTiO3

Magnetic and electronic properties of Neptunium chalcogenides from GGA U SOC and DFT investigations

Pro zkoumání strukturních, elektronických a magnetických vlastností chalcogenidů Neptunia (Np2X5, X = S, Se a Te) byly použity techniky prvo principiálních výpočtů. V literatuře nebyly dříve popsány experimentální nebo teoretické studie jejich fyzikálních vlastností. Přítomnost vysoce lokalizovaných f stavů vyžadovala využití spirálové vazby a přístupu GGA + U, aby bylo správně popsáno spojení f-f. Np2X5 byl nalezen kovový charakter s vysokým magnetickým momentem kvůli přítomnosti Neptunia. Fermi povrchy Np2Te5 vykazovaly větší elektrickou vodivost ve srovnání s Np2Se5 a Np2S5. Bylo zjištěno, že magnetický moment je mezi 13,24 a 13,92 μB, vyvolaný hlavně Npf a d-orbitály, stejně jako spinpolarizace chalcogenů (Te, Se, S) indukovaných Np. Chalkogenidy Neptunia vykazují zajímavé magnetické vlastnosti a měly by být manipulovány s opatrností kvůli jejich radioaktivním vlastnostem.First-principles calculations techniques were employed to explore the structural, electronic and magnetic properties of Neptunium chalcogenides (Np2X5, X = S, Se and Te). No experimental or theoretical studies of their physical properties have been previously reported in the literature. The presence of highly localized f states has requested the employment of the spin orbit coupling and GGA + U approach in order to describe correctly the f–f coupling. Np2X5 was found metallic with high magnetic character due to the Neptunium presence. Fermi surfaces of Np2Te5 have shown a greater electrical conductivity compared to Np2Se5 and Np2S5. The magnetic moment was found to be between 13.24 and 13.92 μB, principally induced by Np f and d-orbitals as well as the spin-polarization of the chalcogenes (Te, Se, S) induced by Np. Neptunium chalcogenides have shown interesting magnetic properties and should be manipulated with precaution due to their radioactive properties

CoCEC: An Automatic Combinational Circuit Equivalence Checker Based on the Interactive Theorem Prover

Checking the equivalence of two Boolean functions, or combinational circuits modeled as Boolean functions, is often desired when reliable and correct hardware components are required. The most common approaches to equivalence checking are based on simulation and model checking, which are constrained due to the popular memory and state explosion problems. Furthermore, such tools are often not user-friendly, thereby making it tedious to check the equivalence of large formulas or circuits. An alternative is to use mathematical tools, called interactive theorem provers, to prove the equivalence of two circuits; however, this requires human effort and expertise to write multiple output functions and carry out interactive proof of their equivalence. In this paper, we (1) define two simple, one formal and the other informal, gate-level hardware description languages, (2) design and develop a formal automatic combinational circuit equivalence checker (CoCEC) tool, and (3) test and evaluate our tool. The tool CoCEC is based on human-assisted theorem prover Coq, yet it checks the equivalence of circuit descriptions purely automatically through a human-friendly user interface. It either returns a machine-readable proof (term) of circuits’ equivalence or a counterexample of their inequality. The interface enables users to enter or load two circuit descriptions written in an easy and natural style. It automatically proves, in few seconds, the equivalence of circuits with as many as 45 variables (3.5 × 1013 states). CoCEC has a mathematical foundation, and it is reliable, quick, and easy to use. The tool is intended to be used by digital logic circuit designers, logicians, students, and faculty during the digital logic design course

Theoretical analysis of an intermediate band in Sn-doped hematite with wide-spectrum solar response

Hematite alpha-Fe2O3 is exposed to be an efficient photocatalytic material for the photoelectrochemical water splitting process under visible light. In the present work, we have improved the photocatalytic activity of hematite by varying tin concentration substituted for Fe in pristine hematite. To investigate the influence of the contents of Sn on the photocatalytic activity, various key properties like electronic structure and optoelectronic properties were studied based on density functional theory using generalized gradient approximation plus on-site Hubbard interaction within the WIEN2k computer program. The results of the electronic band structure show the insulating character of the pristine hematite exhibits a bandgap of 2.17 eV equals to Exp. one. The electronic structure calculations of the Sn-doped hematite explore the engineering of the orbitals around the Fermi level and result in a reduction in the bandgap, which is attributed to the corresponding Sn contents. The doping of Sn in Fe2O3 would introduce sub-bands (intermediate band) in between the valence band maximum (VBM) and Fermi level E-F, and more interestingly, half-filled intermediate bands appear around the Fermi level with the increase of Sn contents. To see the effect of intermediate bands on the optoelectronic features of the Sn-doped hematite, we also calculated the optical properties of pristine and doped hematite, which predict extra peaks assigned to transitions of electrons from intermediate bands in the infrared region. Our findings explore that the presence of intermediate bands facilitates the PEC activity of water splitting of Fe2O3, shifting from visible light to infrared region. Here, we demonstrate the idea of intermediate bands in hematite for distinctive device applications

Density independent hydrodynamics model for crowd coherency detection

We propose density independent hydrodynamics model (DIHM) which is a novel and automatic method for coherency detection in crowded scenes. One of the major advantages of the DIHM is its capability to handle changing density over time. Moreover, the DIHM avoids oversegmentation and thus achieves refined coherency detection. In the proposed DIHM, we first extract a motion flow field from the input video through particle initialization and dense optical flow. The particles of interest are then collected to retain only the most motile and informative particles. To represent each particle, we accumulate the contribution of each particle in a weighted form, based on a kernel function. Next, the smoothed particle hydrodynamics (SPH) is adopted to detect coherent regions. Finally, the detected coherent regions are refined to remove the effects of oversegmentation. We perform extensive experiments on three benchmark datasets and compare the results with 10 state-of-the-art coherency detection methods. Our results show that DIHM achieves superior coherency detection and outperforms the compared methods in both pixel level and coherent region level average particle error rates (PERs), average coherent number error (CNE) and F-score

Teoretické štúdium XANES Ca a S viacerýmy metódami: vlyv plného potenciálu, korovej diery a Eu.

Ca a S K-edge spektra CaS jsou vypočítány pomocí plného-potenciálu metodou vícenásobného rozptylu, metodou FLAPW a metodou finite-difference. Všechny tři techniky vedou k podobným spekterám. Zde se zjistilo, že využití plného potenciálu nevede k významnému zlepšení nad aproximací atomových koulí . Doping CaS s Eu neovlivní významně Ca a S K-hranu XANES CaS.Ca and S K-edge spectra of CaS are calculated by the full-potential Green's function multiple-scattering method, by the FLAPW method and by the finite-difference method. All three techniques lead to similar spectra. Some differences remain close to the edge, both when comparing different calculations with each other and when comparing the calculations with earlier experimental data. Here it is found that using the full potential does not lead to significant improvement over the atomic spheres approximation and that the effect of the core hole can be limited to the photoabsorbing atom alone. Doping CaS with Eu will not affect the Ca and S K-edge XANES of CaS significantly but may give rise to a pre-edge structure not present for clean CaS