This work presents a new technique named Raman strain rosette for the micro-strain measurement of both Raman active and Raman inactive materials. The technique is based on the theoretical model of the carbon nanotube (CNT) strain sensor that applies the resonance and polarization Raman properties of CNTs and calculates the synthetic contributions of uniformly dispersed CNTs to the entire Raman spectrum. In our work, the proposed technique is applied in different experiments on the Raman inactive materials, such as step-by-step uniaxial tensile and Raman mapping around a circular hole. The experimental results reached by the Raman strain rosette are consistent with the actual values as a whole. This study verifies that the Raman strain rosette is applicable to quantitative measurement of all the in-plane components of the strain tensor (including both normal and shear strains) by three polarized Raman detections for each sampling spot on a microscale. The technique is further applicable to achieving the strain fields through Raman mapping.

We developed an experimental metrology for measuring local strain in molecular beam epitaxially (MBE) grown crystalline chalcogenide thin films through micro-Raman spectroscopy. For In2Se3 and Bi2Se3 on c-plane sapphire substrates, the transverse-optical vibrational mode (A1 phonon) is most sensitive to strain. We first calibrated the phonon frequency–strain relationship in each material by introducing strain in flexible substrates. The Raman shift–strain coefficient is −1.97 cm–1/% for the In2Se3 A1(LO + TO) mode and −1.68 cm–1/% for the Bi2Se3 A1g 2 mode. In2Se3 and Bi2Se3 samples exhibit compressive strain and tensile strain, respectively. The observations are compliant with predictions from the opposite relative thermal expansion coefficient between the sample and the substrate. We also map strain cartography near the edge of as-grown MBE samples. In In2Se3, the strain accumulates with increasing film thickness, while a low strain is observed in thicker Bi2Se3 films.

Research on trajectory tracking is crucial for the development of autonomous vehicles. This paper presents a trajectory tracking scheme by utilizing model predictive control (MPC) and preview-follower theory (PFT), which includes a reference generation module and a MPC controller. The reference generation module could calculate reference lateral acceleration at the preview point by PFT to update state variables, and generate a reference yaw rate in each prediction point. Since the preview range is increased, PFT makes the calculation of yaw rate more accurate. Through physical constraints, the MPC controller can achieve the best tracking of the reference path. The MPC problem is formulated as a linear time-varying (LTV) MPC controller to achieve a predictive model from nonlinear vehicle dynamics to continuous online linearization. The MPC-PFT controller method performs well by increasing the effective length of the reference path. Compared with MPC and PFT controllers, the effectiveness and robustness of the proposed method are proved by simulations of two typical working conditions.

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Nervilia fordii (Hance) Schltr. has been widely used as a medicinal and edible herb in Southwest China and Southeast Asia. In this study, NFP-1, a new water-soluble polysaccharidewith a purity of 97.8%, was purified from water extract of Nervilia fordii by DEAE-cellulose and Sephadex G-100 chromatography. NFP-1 has a relative molecular weight of 950 kDa determined by high performance gel-permeation chromatography (HPGPC). Its monosaccharide compositions were analyzed by high performance liquid chromatography (HPLC) after pre-column derivatizing its hydrolysate with 1-phenyl-3-methyl-5-pyrazolone (PMP). NFP-1 mainly consists of galactose, arabinose, rhamnose, and galacturonic acid. Based on FT-IR, methylation and GC-MS analysis, and NMR, the structure unit of NFP-1 was established as →4)-α-Rhap-(2→ 4)-α-GalpA-(1→2)-α-Rhap-(1→2)-α-Rhap-(4→1)-β-Galp-T containing two branch chains of →2,4)-α-Rhap-(1→5)-α-Araf-(1→3)-α-Araf-(1→, and →2,4)-α-Rhap-(1→4)-β-Galp-(1→. The immunomodulatory assays revealed the dual-functionalities of NFP-1. NFP-1 could significantly induce the secretion of nitric oxide (NO), and promote the secretions of TNF-α, IL-6, and IL-1β in RAW264.7 macrophages. NFP-1 could also significantly inhibit the production of NO, depress the secretions of TNF-α, IL-6 and IL-1β in RAW264.7 macrophages activated by lipopolysaccharide (LPS), and promote the production of IL-10 meanwhile. Our study suggested that Nervilia fordii could be an ideal medicinal or functional food due to its dual immunomodulatory activities.

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The present paper is a detailed sort-out and critical review of the foreign literature on tourist satisfaction at destinations in the last decade. Four dimensions that the relevant research surrounded are identified: tourist satisfaction theoretical model; the relation between tourist satisfaction and loyalty, expectation and service quality; the tourists' cultural backgrounds and cultural differences of the tourist satisfaction; and evaluation model of tourist satisfaction at destinations. The limitations of the previous research are briefly discussed, and future research directions are suggested attempting to provide reference and inspiration for the relevant domestic research and the tourism industry.

Five new flavonoid glycosides, namely nervilifordins F-J (1-5), were isolated from the 60% EtOH extract of the aerial parts of Nervilia fordii, along with three first isolated flavonoids (7, 8, and 13) and five known flavonoids (6, 9-12). The structures of new compounds were elucidated on the basis of 1D and 2D NMR and MS studies. Their anti-inflammatory activities were tested by measuring their inhibitory effects on nitric oxide production in lipopolysaccharide-activated RAW264.7 macrophages. Compounds 2 and 5 showed interesting inhibition effects with their EC50 values of 15.15 μM and 14.80 μM, respectively.