Monopoles without magnetic charges: Finite energy monopole-antimonopole configurations in CP1 model and restricted QCD

We propose a new type of regular monopole-like field configuration in quantum chromodynamics (QCD) and CP^1 model. The monopole configuration can be treated as a monopole-antimonopole pair without localized magnetic charges. An exact numeric solution for a simple monopole-antimonopole solution has been obtained in CP^1 model with an appropriate potential term. We suppose that similar monopole solutions may exist in effective theories of QCD and in the electroweak standard model.Comment: 8 pages, 8 figures, 1 table, final version accepted by Phys. Lett.

Subject-specific finite element modelling of the human hand complex : muscle-driven simulations and experimental validation

This paper aims to develop and validate a subject-specific framework for modelling the human hand. This was achieved by combining medical image-based finite element modelling, individualized muscle force and kinematic measurements. Firstly, a subject-specific human hand finite element (FE) model was developed. The geometries of the phalanges, carpal bones, wrist bones, ligaments, tendons, subcutaneous tissue and skin were all included. The material properties were derived from in-vivo and in-vitro experiment results available in the literature. The boundary and loading conditions were defined based on the kinematic data and muscle forces of a specific subject captured from the in-vivo grasping tests. The predicted contact pressure and contact area were in good agreement with the in-vivo test results of the same subject, with the relative errors for the contact pressures all being below 20%. Finally, sensitivity analysis was performed to investigate the effects of important modelling parameters on the predictions. The results showed that contact pressure and area were sensitive to the material properties and muscle forces. This FE human hand model can be used to make a detailed and quantitative evaluation into biomechanical and neurophysiological aspects of human hand contact during daily perception and manipulation. The findings can be applied to the design of the bionic hands or neuro-prosthetics in the future

A utility-based priority scheduling scheme for multimedia delivery over LTE networks

With the mobile networks migrating towards LTE-Advanced and all-IP networks, people expect to connect to the Internet anytime, anywhere and from any IP-connected device. Moreover, nowadays people tend to spend much of their time consuming multimedia content from various devices with heterogeneous characteristics (e.g., TV screen, laptop, tablet, smartphone, etc.). In order to support uninterrupted, continuous, and smooth video streaming with reduced delay, jitter, and packet loss to their customers, network operators must be able to differentiate between their offerings according to device characteristics, including screen resolution. This paper proposes a novel Utility-based Priority Scheduling (UPS) algorithm which considers device differentiation when supporting high quality delivery of multimedia services over LTE networks. The priority decision is based on device classification, mobile device energy consumption and multimedia stream tolerance to packet loss ratio. Simulation results demonstrate the benefits of the proposed priority-based scheduling algorithm in comparison with two classic approaches

DOAS: device-oriented adaptive multimedia scheme for 3GPP LTE systems

The growing popularity of the high-end mobile computing devices – smartphones, tablets, notebooks and more – equipped with high-speed network access, enables the mobile user to watch multimedia content from any source on any screen, at any time, while on the move or stationary. In this context, the network operators must ensure smooth video streaming with the lowest service delay, jitter, and packet loss. This paper proposes a resource efficient Device-Oriented Adaptive Multimedia Scheme (DOAS) built on top of the downlink scheduler in LTE-Advanced systems. DOAS bases its adaptation decision on the end-user device display resolution information and Quality of Service (QoS). DOAS is implemented on top of the Proportional Fair (PF) and the well-known Modified Largest Weighted Delay First (M-LWDF) scheduling algorithms within the 3GPP LTE/LTE-Advanced system. The performance of the proposed adaptive multimedia scheme was analyzed and compared against a non-adaptive solution in terms of throughput, packet loss and PSNR

Device-oriented energy-aware utility-based priority scheduler for video streaming over LTE system

Nowadays people tend to spend most of their time in front of a screen, and expect to be able to connect to the Internet anytime and anywhere and from any type of mobile device. Therefore, fast surfing speed on Internet, high resolution display screen, advanced multi-core processor and lasting battery support are becoming the significant standards in the nowadays mobile devices. In this context the network operators must be able to differentiate between their multiscreen offerings in order to ensure uninterrupted, continuous, and smooth video streaming with minimal delay, jitter, and packet loss. This paper proposes a novel Device-Oriented Energy-Aware Utility-based Priority scheduling (DE-UPS) algorithm which makes use of device differentiation in order to ensure seamless multimedia services over LTE networks. The priority decision is based on the device classification, energy consumption of the mobile device and the multimedia stream tolerance to packet loss ratio

E³DOAS: balancing QoE and energy-saving for multi-device adaptation in future mobile wireless video delivery

Smart devices (e.g. smartphones, tablets, smart-home devices, etc.) have become important companions to most people in their daily activities, and are very much used for multimedia content exchange (i.e. video sharing, real-time/non-real-time multimedia streaming), contributing to the exponential increase in mobile traffic over the current wireless networks. While the next generation mobile networks will provide higher capacity than the current 4G systems, the network operators will face important challenges associated with the outstanding increase of both video traffic and user expectations in terms of their levels of perceived quality or Quality of Experience (QoE). Furthermore, the heterogeneity of mobile devices (e.g. screen resolution, battery life, hardware performance) also impacts severely the end-user QoE. In this context, this paper proposes an Evolved QoE-aware Energy-saving Device-Oriented Adaptive Scheme (E3DOAS ) for mobile multimedia delivery over future wireless networks. E3DOAS makes use of a coalition game-based rate allocation strategy within the multi-device heterogeneous environment, and optimizes the trade-off between the end-user perceived quality of the multimedia delivery and the mobile device energy-saving. Testing has involved a prototype of E3DOAS, a crowd-sourcing-based QoE assessment method to model non-reference perceptual video quality, and an energy measurement testbed introduced to collect power consumption parameters of the mobile devices. Simulation-based performance evaluation showed how E3DOAS outperformed other state of the art multimedia adaptive solutions in terms of energy saving, end-to-end Quality of Service (QoS) metrics and end-user perceived quality