Biasing Effects in Ferroic Materials

In this chapter we present an overview of some important concepts related to the processes and microstructural mechanisms that produce the deformation of hysteresis loops and the loss of their symmetry characteristics in ferroelectric, ferroelastic and ferromagnetic systems. The most discussed themes include: aging and fatigue as primary mechanisms of biased hysteresis loops in ferroelectric/ferroelastic materials, imprint phenomenon as an important biasing process in ferroelectric thin films, the development of an exchange bias field and of specific spin states, such as spin canting and spin-glass-like phases, as the main causes of biased hysteresis loops in different types of magnetic heterostructures. The present discussion leads to the identification of the main differences and possible analogies in the underlying mechanisms of possible biasing effects occurring in the different ferroic systems, which can benefit the theoretical description, modelling, and engineering of multifunctional devices based on ferroic systems experiencing the internal bias phenomena

Learning from Winners: A Strategic Perspective of Improving Freelancers’ Bidding Competitiveness in Crowdsourcing

The rapid growth of crowdsourcing grants freelancers unprecedented opportunities to materialize their expertise by bidding in specific tasks. Despite lowering freelancers’ participation costs, the bidding mechanism meanwhile induces intense competition, rendering it difficult for freelancers to submit competitive bids. Although previous research has disentangled several bidding strategies, scant attention was paid to whether and how freelancers should learn to adjust their bidding strategies and improve bidding competitiveness during the journey of participating in multiple tasks. To fill in this gap, we adapt a set of bidding strategies from auction literature into the crowdsourcing context. Leveraging the lens of vicarious learning, we advance that freelancers’ learning from winners on bidding strategies will enhance their bidding competitiveness, which is moderated by task complexity. Our preliminary results suggest a significant relationship between strategic learning and bidding competitiveness, along with the moderating effect of task complexity. Expected contributions and future schemes are discussed finally

Isolation and Characterization of 89K Pathogenicity Island-Positive ST-7 Strains of Streptococcus suis Serotype 2 from Healthy Pigs, Northeast China

Streptococcus suis is a swine pathogen which can also cause severe infection, such as meningitis, and streptococcal-like toxic shock syndrome (STSS), in humans. In China, most of the S. suis infections in humans were reported in the southern areas with warm and humid climates, but little attention had been paid to the northern areas. Data presented here showed that the virulent serotypes 1, 2, 7, and 9 of S. suis could be steadily isolated from the healthy pigs in the pig farms in all the three provinces of Northeast China. Notably, a majority of the serotype 2 isolates belonged to the 89K pathogenicity island-positive ST-7 clone that had historically caused the human STSS outbreaks in the Sichuan and Jiangsu provinces of China, although the human STSS case caused by S. suis had never been reported in northern areas of China. Data presented here indicated that the survey of S. suis should be expanded to or reinforced in the northern areas of China

Control of spatially homogeneous distribution of heteroatoms to produce red TiO2 photocatalyst for visible-light photocatalytic water splitting

The authors thank National Natural Science Fundation of China (Nos. 51825204, 51572266, 21633009, 51629201), the Major Basic Research Program, Ministry of Science and Technology of China (2014CB239401), the Key Research Program of Frontier Sciences CAS (QYZDB-SSW-JSC039) for the financial support. G. L. is grateful for the award of the Newton Advanced Fellowship.The strong band-to-band absorption of photocatalysts spanning the whole visible light region (400-700 nm) is critically important for solar-driven photocatalysis. Although it is actively and widely used as photocatalyst for various reactions in the past four decades, TiO2 has a very poor ability to capture the whole-spectrum visible light. Here, by controlling the spatially homogeneous distribution of boron and nitrogen heteroatoms in anatase TiO2 microspheres with a predominance of high-energy {001} facets, a strong visible light absorption spectrum with a sharp edge beyond 680 nm is achieved. The red TiO2 with the homogeneous doping of boron and nitrogen obtained shows no increase in defects like Ti3+ that are commonly observed in doped TiO2. More importantly, it has the ability to induce photocatalytic water oxidation to produce oxygen under the irradiation of visible light beyond 550 nm and also photocatalytic reducing water to produce hydrogen under visible light. These results demonstrate the great promise of using the red TiO2 for visible light photocatalytic water splitting and also provide an attractive strategy for realizing the wide-spectrum visible light absorption of wide-bandgap oxide photocatalysts.PostprintPeer reviewe

Rethinking the Open-Loop Evaluation of End-to-End Autonomous Driving in nuScenes

Modern autonomous driving systems are typically divided into three main tasks: perception, prediction, and planning. The planning task involves predicting the trajectory of the ego vehicle based on inputs from both internal intention and the external environment, and manipulating the vehicle accordingly. Most existing works evaluate their performance on the nuScenes dataset using the L2 error and collision rate between the predicted trajectories and the ground truth. In this paper, we reevaluate these existing evaluation metrics and explore whether they accurately measure the superiority of different methods. Specifically, we design an MLP-based method that takes raw sensor data (e.g., past trajectory, velocity, etc.) as input and directly outputs the future trajectory of the ego vehicle, without using any perception or prediction information such as camera images or LiDAR. Our simple method achieves similar end-to-end planning performance on the nuScenes dataset with other perception-based methods, reducing the average L2 error by about 20%. Meanwhile, the perception-based methods have an advantage in terms of collision rate. We further conduct in-depth analysis and provide new insights into the factors that are critical for the success of the planning task on nuScenes dataset. Our observation also indicates that we need to rethink the current open-loop evaluation scheme of end-to-end autonomous driving in nuScenes. Codes are available at https://github.com/E2E-AD/AD-MLP.Comment: Technical report. Code is availabl

Homogeneous doping of substitutional nitrogen/carbon in TiO2 plates for visible light photocatalytic water oxidation

The authors thank National Natural Science Foundation of China (Grant Nos. 51825204, 51572266, 21633009, and 51629201), the Key Research Program of Frontier Sciences CAS (QYZDB‐SSW‐JSC039) for the financial support. G.L. is grateful for the award of the Newton Advanced Fellowship.Extending the light absorption range of wide‐bandgap photocatalysts into the visible light region is significant in terms of fully harvesting and converting solar light. The desirable band‐to‐band redshift of the absorption edge of semiconducting binary metal oxides such as prototypical photocatalyst TiO2 by doping is long targeted but remains a challenge, up to date. Here, by taking the advantage of abundant 1D diffusion channels with rhombus‐like cross‐sections along the c‐axis in the crystal structure of titanium oxalate hydrate to promote the entrance of nitrogen dopant species into the bulk and subsequent thermal topotactic transition in an atmosphere of gaseous ammonia, homogeneous doping of substitutional carbon/nitrogen for oxygen in the TiO2 decahedral plates with a dominant anatase phase is obtained for the first time. The resultant TiO2−x(CN)y with an unusual band‐to‐band visible light absorption spectrum can induce photocatalytic water oxidation to release oxygen under visible light irradiation. This study provides not only a promising visible light–responsive TiO2 photocatalyst, but also an important strategy for developing other solar‐driven photocatalysts.PostprintPeer reviewe