A slip model for micro/nano gas flows induced by body forces

A slip model for gas flows in micro/nano-channels induced by external body forces is derived based on Maxwell's collision theory between gas molecules and the wall. The model modifies the relationship between slip velocity and velocity gradient at the walls by introducing a new parameter in addition to the classic Tangential Momentum Accommodation Coefficient. Three-dimensional Molecular Dynamics simulations of helium gas flows under uniform body force field between copper flat walls with different channel height are used to validate the model and to determine this new parameter

Adult-perpetrated Animal Abuse: Development of a Proclivity Scale

There is a clear discrepancy in the reporting of animal cruelty complaints, prosecutions and convictions suggesting that any prevalence figures of abuse are significant under-representations. Therefore, it can be inferred that there is a large number of animal abusers who are unapprehended. Currently there is no validated tool that assesses the proclivity or propensity to engage in animal abuse amongst members of the general public. Such a tool would enable researchers to study individuals who may think like animal abusers or may be unapprehended offenders themselves. This paper presents the newly developed Animal Abuse Proclivity Scale (AAPS) and some preliminary findings. The results from our two studies show that: (1) the psychometric properties of the AAPS indicate that the scale is a highly reliable measure; (2) the AAPS relates to measures assessing offence-supportive attitudes and reflects the gender differences seen in the literature; and (3) the AAPS demonstrates cross-national validity. These findings support that the AAPS, similar to other offending proclivity measures, is a tool that can be used to examine the factors most related to animal abuse propensity. We discuss how the AAPS can contribute to future developments in theory and practice in the field

Liquid oxygen/liquid hydrogen boost/vane pump for the advanced orbit transfer vehicles auxiliary propulsion system

A rotating, positive displacement vane pump with an integral boost stage was designed to pump saturated liquid oxygen and liquid hydrogen for auxiliary propulsion system of orbit transfer vehicle. This unit is designed to ingest 10% vapor by volume, contamination free liquid oxygen and liquid hydrogen. The final pump configuration and the predicted performance are included

Power allocation for multiband coded OFDM systems with limited feedback

In this paper, we study the power allocation for multiband coded OFDM systems. With limited feedback, we propose an effective power allocation method across OFDM bands to maximize the throughput and achieve the quality of service target. To facilitate the proposed method, two optimization algorithms based on greedy and dynamic programming principles are discussed. The trade-off between performance and complexity is provided. Simulation results show that the proposed power allocation mechanism allows a signal to noise ratio gain of 2 dB at a goodput of 2.5 bit per second per Hz over the multiband OFDM systems with equal power allocation

Digital twin for 5G and beyond

Although many countries have started the initial phase of rolling out 5G, it is still in its infancy with researchers from both academia and industry facing the challenges of developing to its full potential. With the support of Artificial Intelligence, development of digital transformation through the notion of a ‘Digital Twin’ has been taking off in many industries such as smart manufacturing, oil & gas, constructions, bio-engineering, and automotive. However, Digital Twins remain relatively new for 5G networks, despite the obvious potential in helping develop and deploy the complex 5G environment. This paper looks into these topics and discusses how Digital Twin could be a powerful tool to fulfil the potentials of 5G networks and beyond

The volatility structure of the fixed income market under the HJM framework: A nonlinear filtering approach

ABSTRACT. This paper considers the dynamics for interest rate processes within a multi-factor Heath, Jarrow and Morton (1992) specification. Despite the flexibility of and the notable advances in theoretical research about the HJM models, the number of empirical studies is still inadequate. This paucity is principally because of the difficulties in estimating models in this class, which are not only high-dimensional, but also nonlinear and involve latent state variables. This paper treats the estimation of a fairly broad class of HJM models as a nonlinear filtering problem, and adopts the local linearization filter of Jimenez and Ozaki (2003), which is known to have some desirable statistical and numerical features, to estimate the model via the maximum likelihood method. The estimator is then applied to the interbank offered-rates of the U.S, U.K, Australian and Japanese markets. The two-factor model, with the factors being the level and the slope effect, is found to be a reasonable choice for all of the markets. However, the contribution of each factor towards overall variability of the interest rates and the financial reward each factor claims differ considerably from one market to another