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Spatiotemporal modulation offers a variety of opportunities for light manipulations. In this paper, we propose a way towards arbitrary transformation for pulses sequentially propagating within one waveguide in space via temporal waveguide coupling. The temporal waveguide coupling operation is achieved by spatiotemporally modulating the refractive index of the spatial waveguide with a traveling wave through segmented electrodes. We derive the temporal coupled-mode equations and discuss how systematic parameters affect the temporal coupling coefficients. We further demonstrated a temporal Mach-Zehnder interferometer and universal multiport interferometer, which enables arbitrary unitary transformation for pulses. We showcase a universal approach for transforming pulses among coupled temporal waveguides, which requires only one spatial waveguide under spatiotemporal modulation, and hence provide a flexible, compact, and highly compatible method for optical signal processing in time domain.

Supplemental material, sj-docx-1-eae-10.1177_0958305X221133263 for Hydrocarbon regulation and lower temperature pyrolysis of balikun oil shale kerogen by Fei Liu, Weiguang Shi, Tianbao Liu, Wei Li, Liang Sun, Xiangbin Liu, Changming Zhao, Benxian Li, Sunhua Deng, Zhaohui Dong, Chengwu Xu, Xiaofei Fu and Xiuling Yan in Energy & Environment

Supplemental material, sj-docx-1-eae-10.1177_0958305X221133263 for Hydrocarbon regulation and lower temperature pyrolysis of balikun oil shale kerogen by Fei Liu, Weiguang Shi, Tianbao Liu, Wei Li, Liang Sun, Xiangbin Liu, Changming Zhao, Benxian Li, Sunhua Deng, Zhaohui Dong, Chengwu Xu, Xiaofei Fu and Xiuling Yan in Energy & Environment

Online path planning for multiple unmanned aerial vehicle (multi-UAV) systems is considered a challenging task. It needs to ensure collision-free path planning in real-time, especially when the multi-UAV systems can become very crowded on certain occasions. In this paper, we presented a vision-based decentralized collision-avoidance policy for multi-UAV systems, which takes depth images and inertial measurements as sensory inputs and outputs UAV's steering commands. The policy is trained together with the latent representation of depth images using a policy gradient-based reinforcement learning algorithm and autoencoder in the multi-UAV threedimensional workspaces. Each UAV follows the same trained policy and acts independently to reach the goal without colliding or communicating with other UAVs. We validate our policy in various simulated scenarios. The experimental results show that our learned policy can guarantee fully autonomous collision-free navigation for multi-UAV in the three-dimensional workspaces with good robustness and scalability., Comment: Submitted to IEEERSJ International Conference on Intelligent Robots and Systems (IROS) 2022

The rich nontrivial topological phases rooted in the interplay between magnetism and topology in the layered antiferromagnet EuCd2As2 have captured vast attention, especially the ideal Weyl semimetal state realized in the spin-polarized ferromagnetic (FM) structure driven by a moderate external magnetic field. In this work, combining high-pressure magnetotransport measurements, structure chracterizations and first principles calculations, we find that application of pressure can also realize the ideal Weyl state in EuCd2As2 through driving the in-plane antiferromagnetic state across an intermediate in-plane FM state then into the out-of-plane FM state. Our high-pressure angle dispersive X-ray diffraction and X-ray absorption near-edge spectroscopy measurements excluded structure transition and/or change of Eu2+ valence state as the sources for the magnetic phase transitions. Alternatively, the apparently reduced axial ratio (c/a) and compressed Eu-layer space distance should play important roles. Our result provides an alternative way to realize the ideal Weyl semimetal state in EuCd2As2 and would be instructive for the exploration of exotic topological properties in such layered magnetic topological phase with strongly competing magnetic exchanges by using high pressure., Comment: main text 16 pages,4 figures and SI 8 pages, 4 figures

Additional file 2: Table S1. Comparison of vitro antifungal susceptibility of candida between mono-candidemia and mixed C/B-BSIs.

Through either elements intercalation or application of pressure, transition metal dichalcogenide 1T-TiSe2 exhibits superconductivity in proximity to a charge density wave (CDW) quantum critical point (QCP), thus providing an ideal avenue to study the correlation between the two symmetry-breaking exotic quantum electronic states. We report herein that, in addition to the well-known superconducting dome that emerges within the low pressure range of 2 - 4 GPa and peaks with the maximal Tc of about 1.8 K, the pressure induces another separate superconducting transition starting around 15 GPa with a substantially higher Tc that reaches 5.6 K at about 21.5 GPa. The high-pressure X-ray diffraction and Raman spectroscopy measurements unveil that the superconductivity reentrant is caused by a first-order structural phase transition (from P-3m1 space group to Pnma space group), which is also supported by the density functional theory calculation. A comparative theoretical calculation also reveals that the conventional phonon-mediated mechanism can account for the superconductivity of 1T-TiSe2 under low pressure, while the electron-phonon coupling of 4O-TiSe2 under high pressure is too weak to induce the superconductivity with a Tc as high as 5.6 K. This implies that the emergent superconductivity in the 4O-TiSe2 may have an unconventional origin. Our finding would open a new window toward the discovery of more exotic quantum states in transition metal dichalcogenides via high pressure., Comment: 15 pages, 4 figures

In precision manufacturing industry, requirements for surface quality are very high. It is important to accurately predict the machined surface errors to reduce manufacturing costs and lead times as well as develop fixturing scheme to optimize machining quality. This paper presents a contribution for predicting the machined surface errors where fixture-workpiece system dynamic effects during milling process are considered. The combined effect of clamping and milling on machined surface errors prediction is taken into account, and finite element analysis is developed to analyze the workpiece deformation. In finite element analysis environment, the static analysis and explicit dynamic analysis are used to calculate the static deformation due to clamping force and the dynamic deformation due to milling force. Milling forces are applied to the manufacturing points step by step. The chip removal effect is taken into account based on element death technique, and every fixture locator is modeled as a virtual spring-damper system to emulate the fixture-workpiece contact points. The developed methodology has been verified by a set of end milling experiments for ten fixture layouts. The measured and predicted results are in good agreement, and the results also illustrate that the closer the triangle formed by the three locators in the primary datum is to an equilateral triangle, the smaller machined surface errors will be.

Goals The objective of this study was to estimate the direct medical costs associated with the treatment of chronic hepatitis B (CHB) infection and its complications in China. Background CHB infection is a major health problem in China, with an estimated 112 million chronic carriers. However, the economic burden associated with CHB and its complications has not been well characterized. Study A retrospective analysis of the medical records of a sample of patients with CHB from Beijing, China was conducted. The utilization and costs were estimated for four illness stages associated with CHB (CHB infection, compensated cirrhosis, decompensated cirrhosis, and hepatocellular carcinoma). Annual utilization and costs were estimated for inpatient, outpatient, and medications for each illness stage and valued in year 2002 U.S. dollars (currency conversion was based on a 2002 exchange rate of 8.271 Chinese Yuan Renminbi = U.S. 1 dollar). Results A total of 837 patients were identified for inclusion in the study. The average annual treatment costs per person were as follows: CHB, US 142 dollars; compensated cirrhosis, US 185 dollars; decompensated cirrhosis, US 1702 dollars; and hepatocellular carcinoma, US 4741 dollars. Conclusions The results from this analysis provide estimates of the costs associated with CHB and its complications in China and show that progression of the disease is associated with increasing healthcare costs. These estimates can be used to evaluate the cost-effectiveness of intervention.