Papers by Keyword: Occupation

Abstract: Experimental measurements have been focused on the issue of change in reverberation time T20 and T30 (s) in a selected room (classroom) due to its occupancy by persons (students) and changes in reverberation time T20 and T30 (s) as a result of the excitation signal during measurement. Reverberation time was measured in a standard room at the Faculty of Civil Engineering of the Slovak Technical University in Bratislava (classroom B318) by the use of NORSONIC (NORSONIC NOR 280 amplifier, an omnidirectional sound source - NORSONIC NOR 270, NORSONIC TYPE 118, and microphone and preamplifier). The room (classroom B318) was selected as a model classroom in terms of its dimensions, i.e. volume (225 m3), arrangement of furniture, and maximum number of students during standard lectures (up to 24 people). The main task of this study was the inter-comparison of measurement results of reverberation times T20 and T30 (s), with regard to room occupancy of students (100%, 50%, 0%), the position of students (sitting and standing), and the excitation signal (pink noise, white noise, impulse - bursting of an inflated balloon).

Abstract: Using the first principles calculation method calculated the Mg substitutional atoms occupying law in LaNi₃ alloy. The results of total energy showed ,when Mg atoms occupy the bit of 6c,LaNi₃ alloy is more stable. And substitutional atoms tend to non adjacent. The result of size effect and electronic structure showed that ,the size effect is a major determinant of substitutional Mg substitutional atoms.

Abstract: This research adopted constrained k-prototypes algorithm to analyze the database that contains 294 cases of fatal falls between the years 2003 and 2010 within the Taiwanese construction industry. The objective of this study is to explore the circumstances of the fatal falls. The results of the analysis indicate that the primary circumstances under which the accidents occurred include the professional category of other specialized construction businesses; hazardous mediums such as scaffolding, support frame, stairs, stairways, and the openings, etc.; the time period between 9:00 am and 11:00 am; the falling height between 0 and 10meters. Meanwhile, not adopting safe construction methods is a major indirect factor that contributes to the accidents. The fundamental factors contributing to the accidents include not clearly informing the subcontractors of the conditions of the work environment, risk factors, labor health and safety regulations as well as the necessary measures to ensure the health and safety prior to the project commences.

Abstract: The electronic structure and magnetic properties of the (Co1-xFex)Tet(CoxFe2-x)OctO4 spinels (x is defined as the degree of inversion) scenario are investigated theoretically from first-principles, using generalized gradient approximation (GGA) method for the systems with strong coulomb correlations, which gives a correct description of the electronic structure. The GGA+U method gives an improved qualitative result compared with the GGA not only for the excited-state properties such as energy gaps but also for the ground-state properties such as magnetic moments and crystal parameters. The nominal valence of the transition metal elements and the ground state structure have been established based on the study of variation of the cation distribution (x=0.0, 0.25, 0.5, 0.75 and 1.0) over the tetrahedral and octahedral sites. The site-preference calculation on bulk systems indicates that Co2+ ions strongly prefer the octahedral B sites, and the electronic structure and magnetic properties of cobalt ferrites highly depend on the cation distributions even though the chemical composition of the compound does not change. The results are in good agreement with the available experimental data and most of the other theoretical results.