Analysis on Factors Affecting the Self-Repair Capability of SMA Wire Concrete Beam

Crack expansion of concrete is the initial damage stage of structures, which may cause greater damage to structures subject to long-term loads or under extreme conditions. In recent years, the application of intelligent materials to crack self-repair has become a hotspot among researchers. In order to study the influence of factors on the self-repair capability of shape memory alloy (SMA) wire concrete beam, both theoretical and experimental methods were employed for analysis. For the convenience of experiment, composite materials (epoxy cement mortar and silicone polymer clay) instead of concrete were used. The SMA wires were externally installed on and internally embedded in epoxy resin cement mortar beams and silicone polymer clay beams. Comparison of crack repair situation between two installation methods turns out that both methods possess their own advantages and disadvantages and should be employed according to the actual situation. The influence of unbonded length on the self-repair capability of embedded type SMA wire beams and the necessary minimum unbonded length to achieve self-repair function were studied. The results state clearly that the longer the unbonded length is, the better the crack repair situation is

Intelligent resource scheduling for 5G radio access network slicing

It is widely acknowledged that network slicing can tackle the diverse use cases and connectivity services of the forthcoming next-generation mobile networks (5G). Resource scheduling is of vital importance for improving resource-multiplexing gain among slices while meeting specific service requirements for radio access network (RAN) slicing. Unfortunately, due to the performance isolation, diversified service requirements, and network dynamics (including user mobility and channel states), resource scheduling in RAN slicing is very challenging. In this paper, we propose an intelligent resource scheduling strategy (iRSS) for 5G RAN slicing. The main idea of an iRSS is to exploit a collaborative learning framework that consists of deep learning (DL) in conjunction with reinforcement learning (RL). Specifically, DL is used to perform large time-scale resource allocation, whereas RL is used to perform online resource scheduling for tackling small time-scale network dynamics, including inaccurate prediction and unexpected network states. Depending on the amount of available historical traffic data, an iRSS can flexibly adjust the significance between the prediction and online decision modules for assisting RAN in making resource scheduling decisions. Numerical results show that the convergence of an iRSS satisfies online resource scheduling requirements and can significantly improve resource utilization while guaranteeing performance isolation between slices, compared with other benchmark algorithms

Time at treatment of severe retinopathy of prematurity in China: recommendations for guidelines in more mature infants.

PURPOSE: To investigate the postmenstrual (PMA) age at treatment of severe retinopathy of prematurity (i.e. Type 1 prethreshold or threshold) in infants in a tertiary referral center in China. PRINCIPAL FINDINGS: 76.6% (359/469) of infants were treated for threshold disease. 67.5% (317/469) of infants had a birth weight (BW) of 1250 g or above and almost 30% (126) had a gestational age (GA) of 32 weeks or above. There was little difference in the characteristics of infants treated for Type 1 prethreshold or threshold ROP. After controlling for GA, PMA age at treatment was highest in infants with BW ≥2000 g (mean PMA 40.3±4.4 weeks, p34 weeks, p<0.001). For every three weeks increase in GA there was a two-week increase in PMA at treatment (R2 = 0.20, p<0.001). The time at treatment of Type 1 prethreshold disease was similar to that for threshold disease i.e. chronological age 5.6∓7.4 weeks, or PMA 34.1∓40.2 weeks but the lower end of the 95% confidence interval for chronological age for Type 1 prethreshold disease among infants with BW ≥2000 g was 3.7 weeks (i.e. before the recommended interval of 4∓6 weeks after birth). SIGNIFICANCE: The Chinese guidelines regarding timing of the first examination are appropriate for infants with BW <2000 g, but more mature infants should be examined a little earlier, at 3 weeks after birth, in order to detect Type 1 prethreshold disease which has a better prognosis than threshold

Robust Stereoscopic Crosstalk Prediction

We propose a new metric to predict perceived crosstalk using the original images rather than both the original and ghosted images. The proposed metrics are based on color information. First, we extract a disparity map, a color difference map, and a color contrast map from original image pairs. Then, we use those maps to construct two new metrics (Vdispc and Vdlogc). Metric Vdispc considers the effect of the disparity map and the color difference map, while Vdlogc addresses the influence of the color contrast map. The prediction performance is evaluated using various types of stereoscopic crosstalk images. By incorporating Vdispc and Vdlogc, the new metric Vpdlc is proposed to achieve a higher correlation with the perceived subject crosstalk scores. Experimental results show that the new metrics achieve better performance than previous methods, which indicate that color information is one key factor for crosstalk visible prediction. Furthermore, we construct a new data set to evaluate our new metrics

Experimental Application of Intelligent Robot Technology in Antarctic Scientific Expedition

Intelligent robot technology has great potential for application in polar scientific expedition. During the 24th Chinese Antarctic Expedition in the summer of 2007/08, our ice-snow surface mobile and low-flying robots were successfully employed for the first time in the Antarctic. This paper firstly gives a brief introduction to the intelligent robot technology developed abroad and used in the Antarctic, then focuses on the ice-snow surface mobile and low-flying robots developed by China as well as their field trials in the Antarctic. Moreover, the authors have considered the potential demand for the intelligent robot technology in China's Antarctic scientific expedition, in the hope of providing some reference for the future development of robot technologies

A general model of hormesis in biological systems and its application to pest management

Hormesis, a phenomenon whereby exposure to high levels of stressors is inhibitory but low (mild, sublethal and subtoxic) doses are stimulatory, challenges decision-making in the management of cancer, neurodegenerative diseases, nutrition and ecotoxicology. In the latter, increasing amounts of a pesticide may lead to upsurges rather than declines of pests, ecological paradoxes that are difficult to predict. Using a novel re-formulation of the Ricker population equation, we show how interactions between intervention strengths and dose timings, dose–response functions and intrinsic factors can model such paradoxes and hormesis. A model with three critical parameters revealed hormetic biphasic dose and dose timing responses, either in a J-shape or an inverted U-shape, yielding a homeostatic change or a catastrophic shift and hormetic effects in many parameter regions. Such effects were enhanced by repeated pulses of low-level stimulations within one generation at different dose timings, thereby reducing threshold levels, maximum responses and inhibition. The model provides insights into the complex dynamics of such systems and a methodology for improved experimental design and analysis, with wide-reaching implications for understanding hormetic effects in ecology and in medical and veterinary treatment decision-making. We hypothesized that the dynamics of a discrete generation pest control system can be determined by various three parameter spaces, some of which reveal the conditions for occurrence of hormesis, and confirmed this by fitting our model to both hormetic data from the literature and to a non-hormetic dataset on pesticidal control of mirid bugs in cotton

Singular Cucker-Smale Dynamics

The existing state of the art for singular models of flocking is overviewed, starting from microscopic model of Cucker and Smale with singular communication weight, through its mesoscopic mean-filed limit, up to the corresponding macroscopic regime. For the microscopic Cucker-Smale (CS) model, the collision-avoidance phenomenon is discussed, also in the presence of bonding forces and the decentralized control. For the kinetic mean-field model, the existence of global-in-time measure-valued solutions, with a special emphasis on a weak atomic uniqueness of solutions is sketched. Ultimately, for the macroscopic singular model, the summary of the existence results for the Euler-type alignment system is provided, including existence of strong solutions on one-dimensional torus, and the extension of this result to higher dimensions upon restriction on the smallness of initial data. Additionally, the pressureless Navier-Stokes-type system corresponding to particular choice of alignment kernel is presented, and compared - analytically and numerically - to the porous medium equation