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AbstractThis paper aims to investigate a class of boundary value problems generated by a third-order differential equation with distributional potentials and some dissipative boundary conditions. We first construct an operator related to the problem, then prove that the operator is dissipative and show some eigenvalue properties of this operator. Further using Krein’s theorem we prove the completeness theorems of the operator. [ABSTRACT FROM AUTHOR]

Based on the static capacitance-voltage (${C}-{V}$) model, a new analytical frequency-dependent ${C}-{V}$ model of thin-film transistors (TFTs) is derived from a modified transmission line method (TLM), which is built by embedding an equivalent circuit corresponding to the trapped electrons effect into the traditional TLM. The proposed model is well verified by the measured ${C}-{V}$ characteristics of bottom-gated indium-zinc–oxide (IZO) TFTs with ${W} / {L} =100 \boldsymbol {\mu }{\text {m}} /10 \boldsymbol {\mu }\text {m}$ and ${W} / {L} =100 \boldsymbol {\mu }\text {m} /40 \boldsymbol {\mu }\text {m}$ , where frequencies vary from 1 kHz to 1 MHz. The cutoff frequency of metal oxide TFTs is furthermore analyzed based on the proposed model compared with the traditional TLM. [ABSTRACT FROM AUTHOR]

This work was aimed to experimentally and theoretically investigate the formability of a new magnesium alloy sheet at room temperature. The fracture forming limit diagram was predicted by MMC3 and DF2014 models, where the non-linear strain path effect was taken into account by means of damage accumulation law. In order to obtain the instantaneous values of the stress triaxiality and the Lode parameter during the deformation process, strains tracked by digital image correlation technique were transformed into stresses based on the constitutive equations. The fracture forming limit diagram predicted by the fracture models was compared with the forming limits obtained by ball punch deformation tests. The prediction errors were evaluated by the accumulative damage values, which verified the advantages of ductile fracture models in predicting the forming limits of the magnesium alloy sheets. [ABSTRACT FROM AUTHOR]

Automatic Identification System(AIS) satellite constellation is able to monitor ships all around the world through receiving AIS message, but its performance is affected by message collision. This paper analyzes the message collision of AIS by simulating maritime AIS communication with MATLAB software. The result shows that under different requirements and conditions, there always exists optimal antenna coverage of space-borne AIS receiver. The simulation and analysis provide reference for microsatellite design. [ABSTRACT FROM AUTHOR]

We analyzed multidimensional biodiversity (including species diversity, functional diversity, and phylogenetic diversity) of needle-broadleaf mixed forests of Abies fargesii var. faxoniana-Betula spp. and needleleaf forests of A . fargesii var. faxoniana in the subalpine regions of eastern edge of Qinghai-Tibet Plateau. We measured leaf functional traits including leaf area, leaf thickness, leaf dry matter content, and specific leaf area. The results showed that leaf thickness (0.28 mm) and leaf dry matter content (319.86 mg·g -1 ) in the needle-broadleaf mixed forests were significantly lower than in the needleleaf forest (0.39 mm and 371.33 mg·g -1 , respectively), while specific leaf area (192.74 cm 2 ·g -1 ) was significantly higher (100.91 cm 2 ·g -1 ). Leaf area showed no significant difference between the two forest communities (27.88 and 26.63 cm 2 , respectively). The phylogenetic signals of all leaf functional traits were significant, except for leaf thickness. The phylogenetic structure of the needle-broadleaf mixed forests and needleleaf forest communities tended toward divergence. Shannon diversity index, Simpson diversity index, species richness, functional richness, functional dispersion, Rao's quadratic entropy, and phylogenetic diversity in the needle-broadleaf mixed forests were all significantly higher than in the needleleaf forest, and these indices were significantly positively correlated. Competitive exclusion played a major role in the assembly of subalpine forest communities, and species diversity, functional diversity, and phylogenetic diversity exhibited synchrony.

The natural abundance of stable carbon and nitrogen isotopes (δ 13 C and δ 15 N) in leaves can provide comprehensive information on the physiological and ecological processes of plants and has been widely used in ecological research. However, recent studies on leaf δ 13 C and δ 15 N have focused mainly on woody species, few studies have been conducted on herbs in different vegetation types, and their differences and driving factors are still unclear. In this study, we focused on the herbs in subalpine coniferous forests, alpine shrublands, and alpine mea-dows on the eastern Qinghai-Tibet Plateau, and investigated the differences in leaf δ 13 C and δ 15 N of herbs and the driving factors. The results showed that there were significant differences in leaf δ 13 C and δ 15 N values of herbs among different vegetation types, with the highest δ 13 C and δ 15 N values in alpine meadows, followed by alpine shrublands, and the lowest in subalpine coniferous forests. Using variation partitioning analysis, we revealed that differences in leaf δ 13 C and δ 15 N of herbs among various vegetation types were driven by both leaf functional traits and climate factors, with the contribution of leaf functional traits being relatively higher than that of climate factors. Hierarchical partitioning results indicated that mean annual temperature (MAT), chlorophyll content index, leaf nitrogen content per unit area (N area ), and leaf mass per area were the main drivers of leaf δ 13 C variations of herbs across different vegetation types, while the relative importance of N area and MAT for variation in leaf δ 15 N of herbs was much higher than those other variables. There was a strong coupling relationship between leaf δ 13 C and δ 15 N as indicated by the result of the ordinary least squares regression. Our findings could provide new insights into understanding the key drivers of leaf δ 13 C and δ 15 N variations in herbs across different vegetation types.