Processing Parameters for Selective Laser Melting (SLM) of Gold

Research into laser processing of different metals has enabled Solid Freeform Fabrication (SFF) processes to produce parts for a wide variety of applications. However, less focus has been made on the processing of precious metals. Currently little research has been reported on the processing of precious metals and alloys using the Selective Laser Melting (SLM) process. Here we present an initial investigation into the processing of 24 carat gold (Au) powder using a SLM system. Gold powder was tested for apparent density, tap density, particle shape and size distribution. A quality check of the specimen was carried out using a Scanning Electron Microscope (SEM) for sinterability and occurrence of porosity. Significant processing parameters were also identified.Mechanical Engineerin

Influence of temperature on the performance of a full-scale activated sludge process operated at varying solids retention times whilst treating municipal sewage

In this study, the solid retention time (SRT) was varied with the ambient temperature for a full-scale municipal activated sludge plant with capacity of 200,000 PE (Population Equivalent) located in a humid sub-tropical environment. The effects of ambient temperature on treatment performance were investigated. Off-line samples were collected and analyzed from the treatment plant. The actual temperature variation during the study period was divided into three overlapping ranges and the SRT was adjusted accordingly with temperature in order to achieve the desired effluent quality. The plant’s observed effluent quality and thereby its overall removal efficiency was evaluated in terms of measuring standard biochemical parameters. The results indicate that significant improvement in effluent quality can be obtained by applying the variable SRT (5–7 days) dependent on temperature variation

Temperature and finite-size effects in collective modes of superfluid Fermi gases

We study the effects of superfluidity on the monopole and quadrupole collective excitations of a dilute ultra-cold Fermi gas with an attractive interatomic interaction. The system is treated fully microscopically within the Bogoliubov-de Gennes and quasiparticle random-phase approximation methods. The dependence on the temperature and on the trap frequency is analyzed and systematic comparisons with the corresponding hydrodynamic predictions are presented in order to study the limits of validity of the semiclassical approach.Comment: 9 pages, 4 figure

The Shapley-Folkman Theorem and the Range of a Bounded Measure: An Elementary and Unified Treatment

We present proofs, based on the Shapley-Folkman theorem, of the convexity of the range of a strongly continuous, finitely additive measure, as well as that of an atomless, countably additive measure. We also present proofs, based on diagonalization and separation arguments respectively, of the closure of the range of a purely atomic or purely nonatomic countably additive measure. A combination of these results yields Lyapunov's celebrated theorem on the range of a countably additive measure. We also sketch, through a comprehensive bibliography, the pervasive diversity of the applications of the Shapley-Folkman theorem in mathematical economics.

A review of the perturbation theory as applied to the determination of geopotential

Satellite theory to determine geopotential from orbital motion of artificial earth satellite

Relativistic Quantum Games in Noninertial Frames

We study the influence of Unruh effect on quantum non-zero sum games. In particular, we investigate the quantum Prisoners' Dilemma both for entangled and unentangled initial states and show that the acceleration of the noninertial frames disturbs the symmetry of the game. It is shown that for maximally entangled initial state, the classical strategy C (cooperation) becomes the dominant strategy. Our investigation shows that any quantum strategy does no better for any player against the classical strategies. The miracle move of Eisert et al (1999 Phys. Rev. Lett. 83 3077) is no more a superior move. We show that the dilemma like situation is resolved in favor of one player or the other.Comment: 8 Pages, 2 figures, 2 table

Sensitive Coverage Saves Lives: Improving media portrayal of suicidal behaviour

The report outlines the results of consultations with journalists, suicide prevention agencies and mental health groups conducted by the journalism ethics charity MediaWise. It makes recommendations for action by media organisations and suicide prevention agencies

On Large Games with a Bio-Social Typology

We present a comprehensive theory of large non-anonymous games in which agents have a name and a determinate social-type and/or biological trait to resolve the dissonance of a (matching-pennies type) game with an exact pure-strategy Nash equilibrium with finite agents, but without one when modeled on the Lebesgue unit interval. We (i) establish saturated player spaces as both necessary and sufficient for an existence result for Nash equilibrium in pure strategies, (ii) clarify the relationship between pure, mixed and behavioral strategies via the exact law of large numbers in a framework of Fubini extension, (iii) illustrate corresponding asymptotic results.

Association between socio-economic status and health of older adults in rural Bangladesh and India: a comparative cross-sectional study

Inequalities in health are noticeable among older people in many developing countries, driven by poor social protection systems and low socio-economic status (SES). The present study attempts to examine the effects of SES on health of older adults, and related gender differences, in rural Bangladesh and India using standardized data collection instruments. The study uses the INDEPTH-WHO SAGE Matlab, Bangladesh and Pune District, India datasets. Quintiles of wealth and educational attainment are used as the indicators of socio-economic status, while self-rated health, quality of life, health state, and disability level are used as health indicators. In multiple regression models, both SES indicators are significantly associated with each health status indicator in older adults in Bangladesh, whereas, in India, they are found to be not consistently associated with the four health indicators. Highest level of education is a better predictor of the four health indicators than wealth among older adults in both countries. The findings have profound implications with regard to designing health intervention programmes for older adult populations in both countries