Coil-to-globule transition by dissipative particle dynamics simulation

The dynamics of a collapsing polymer under a temperature quench in dilute solution is investigated by dissipative particles dynamics. Hydrodynamic interactions and many-body interaction are preserved naturally by incorporating explicit solvent particles in this approach. Our simulation suggests a four-stage collapse pathway: localized clusters formation, cluster coarsening in situ, coarsening involving global backbone conformation change into a crumpled globule, and compaction of the globule. For all the quench depths and chain lengths used in our study, collapse proceeds without the chain getting trapped in a metastable “sausage” configuration, as reported in some earlier studies. We obtain the time scales for each of the first three stages, as well as its scaling with the quench depths ξ and chain lengths N. The total collapse time scales as τ_c ~ ξ^(−0.46 ± 0.04)N^(0.98 ± 0.09), with the quench depth and degree of polymerization

First-hop-quality-aware dynamic resource allocation for amplify-and-forward opportunistic relaying assisted SC-FDMA

In this paper we exploit the benefits of the diversity gains arising from a cluster of opportunistic relays (OR) and from the independently fading subcarriers of multiple users. Our goal is to improve the energy-efficiency of the OR assisted single-carrier frequency-division multiple-access (SC-FDMA) uplink using amplify-and-forward (AF), where the direct transmission (DT) link is unavailable. By assuming that the pilot aided channel quality information (CQI) of all the users may be exchanged amongst the cooperating relays, we propose two joint dynamic resource allocation (DRA) schemes based on the so-called ’first-hop quality awareness’. Our results demonstrate that compared to the DT benchmark, the proposed joint DRA schemes are capable of achieving a power reduction of 10dB for a single-antenna base station (BS) receiver, albeit for a multi-antenna BS the power-reduction remains more modest

Frequency-Domain Turbo Equalisation in Coded SC-FDMA Systems: EXIT Chart Analysis and Performance

In this paper, we investigate the achievable performance of channel coded single-carrier frequency division multiple-access (SC-FDMA) systems employing various detection schemes, when communicating over frequency-selective fading channels. Specifically, three types of minimum mean-square error (MMSE) based frequency-domain (FD) turbo equalisers are considered. The first one is the turbo FD linear equaliser (LE). The second one is a parallel interference cancellation (PIC)-assisted turbo FD decision-feedback equaliser (DFE). The final one is the proposed hybrid interference cancellation (HIC)-aided turboFD-DFE, which combines successive interference cancellation (SIC) with iterative PIC and decoding. The benefit of interference cancellation (IC) is analysed with the EXtrinsic Information Transfer (EXIT) charts. The performance of the coded SC-FDMA systems employing the above-mentioned detection schemes is investigated with the aid of simulations. Our studies show that the IC techniques achieve an attractive performance at a moderate complexity

La construcción ecléctica de las novelas de Álvaro Pombo

Programa de Doctorado en Humanidades por la Universidad Carlos III de MadridPresidente: Epícteto José Díaz Navarro.- Secretario: Manuel Ángel Candelas Colodrón.- Vocal: Lucía López Rubi

Research and Practice of Innovation and Entrepreneurship Education in Petroleum Colleges Based on OBE Concept

Deepening the research on the topic of “Research on the current situation of innovation and entrepreneurship practice among college students and analysis of response strategies” is of great value to the healthy operation and coordinated development of college students, higher education institutions, the whole society and the country, and plays a positive role in creating the excellent trend of mass entrepreneurship and innovation in the whole society. It plays a great role in promoting the optimization and adjustment of the economic and industrial structure, the rationalization of market resources, the increase of employment opportunities, the improvement of employment quality and the improvement of people’s living standards. At the same time, combined with the support of sociology and related innovation and entrepreneurship theories, the study from a new perspective provides a theoretical basis and practical guidance for university students to participate in innovation and entrepreneurship activities, and provides certain reference value for further in-depth study of social innovation and entrepreneurship development work