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Interval type-2 trapezoidal fuzzy (IT2TrF) number is a powerful tool to depict fuzzy information. Information measures methods have received more and more attention in recent years as they play an important role in decision-making theory. A new multi-attribute decision-making (MADM) method supported by IT2TrF information measures is investigated in this paper under the IT2TrF information environment. Firstly, three axiomatic definitions of IT2TrF information measures are introduced, which include information entropy, similarity measure and cross-entropy. Secondly, with the help of the exponential function, we formulate some information measure formulas, which are followed by the proofs that the exponential entropy, exponential similarity measure and exponential cross-entropy fit the three axiomatic definitions. Subsequently, a novel IT2TrF MADM method is designed, in which the IT2TrF exponential entropy and cross-entropy are utilized to generate the attribute weights, the IT2TrF exponential similarity measure is employed to obtain the closeness degree of the ideal solution and derive the most satisfying solution. Lastly, we provide a numerical example of corporate investment to demonstrate the applicability and feasibility of the proposed MADM method. The robustness and merits of the developed MADM method are highlighted by the comparative analysis.

Rate constants and thermochemical data for H-atom abstraction reactions from 2-methyl-2-butanol by hydroxyl radicals and the subsequent β-scission reactions of the product radicals were calculated.

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(1) Background: The prevalence of allergic rhinitis (AR) and asthma has increased rapidly in China. However, perceptions of respiratory allergies and barriers to their management have not attracted enough attention. (2) Objective: To investigate the prevalence of, parents’ perceptions of and their unmet needs for information concerning respiratory allergies in a 3- to 16-year-old children population. (3) Methods: A cross-sectional survey was conducted from June to July 2021 in three schools in Wuhan, China. A total of 1963 participants were recruited through cluster sampling for their parents to complete an online questionnaire regarding respiratory allergic symptoms. The diagnosis of respiratory allergies was based on self-reported symptoms and face-to-face physician evaluation. All the participants with respiratory allergies were asked to complete the Brief Illness Perception Questionnaire (B-IPQ), the Asthma Knowledge Questionnaire (AKQ) and a questionnaire regarding their unmet needs for disease management. (4) Results: The prevalence of respiratory allergies was 29.3% (576/1963) in the 3- to 16-year-old population, among whom AR accounted for 25.7%; asthma, 1.8% and AR-complicated asthma (AR&Asthma), 1.9%. The total B-IPQ score was 40.2 ± 10.9 in the participants with respiratory allergies, and there were no differences among the AR, asthma and AR&Asthma groups (all p > 0.05). The B-IPQ score correlated significantly with symptom onset time and a history of atopic dermatitis (p < 0.01). Nearly one fifth, 18.9%, of the participants with respiratory allergies never went to hospital for treatment, but those with higher B-IPQ scores were more likely to seek professional treatment (p < 0.001). The accuracy rates of AKQ were 72.5% in the participants with asthma and 76.7% in those without asthma (p = 0.147). Among the 576 participants with respiratory allergies, 568 (98.6%) had tried to obtain disease-management information from online platforms, and 55.5% (315/568) were dissatisfied with current platforms; the reasons included incomprehensive contents of illness (45.7%), lack of voice from leading experts (40.3%), too many advertisements (37.5%) and similar contents on different platforms (36.8%). (5) Conclusions: The prevalence of respiratory allergies is high in the 3- to 16-years old population in Wuhan, China. Yet the parents’ perceptions of respiratory allergies and knowledge of asthma are insufficient. It is crucial to increase parents’ awareness of the illness and facilitate their access to truly informative and professional platforms.

This study investigates the elasto-plastic buckling behaviour of aluminium alloy cylindrical reticulated shells with gusset joints by means of numerical analysis. First, a numerical model considering joint semi-rigidity is established. A comparison of the linear and non-linear buckling behaviour of semi-rigid jointed and rigid jointed shells, reveals that joint semi-rigidity can reduce the buckling capacity of cylindrical reticulated shells severely. This should be considered in the design process. In addition, the support condition of cylindrical reticulated shells also has an impact on their buckling behaviour. Second, a parametric analysis scheme is proposed to investigate the influence of the rise-to-span ratios, length-to-span ratios, span-to-thickness ratios, loading conditions, and initial geometric imperfections on the elasto-plastic buckling behaviour of aluminium alloy cylindrical reticulated shells with gusset joints. It is observed that the elasto-plastic behaviour is less sensitive to the rise-to-span ratios, whereas it is sensitive to the other parameters. Finally, to facilitate practical engineering, formulae to estimate the elasto-plastic buckling capacity of aluminium alloy cylindrical reticulated shells are derived based on 17,280 numerical analysis results. The regression performance of the formulae with respect to the numerical results is effective. Hence, the time-consuming elasto-plastic analysis can be circumvented in the design process.

Medical innovation has consistently been an essential subject and a source of support for public health research. Furthermore, improving the level of medical research and development is of great concern in this field. This paper highlights the role of big data in public medical innovation. Based on a sample of China&rsquo, s listed firms in the medical industry from 2013 to 2018, this paper explores the exogenous shock effect of China&rsquo, s big data medical policy. Results show that the construction of the medical big data platform effectively promotes innovation investment and the innovation patent of medical firms. In addition, the heterogeneity of this promoting effect is reflected in firm size through the overcoming of different innovation bottlenecks. The research conclusions support the positive significance of the macro-led implementation of the medical big data platform, and suggest that the positive economic externalities generated by this policy are critical to public health.

By inversing the signal and idler in a two-stage noncollinear optical parametric amplifier which is, respectively, pumped by the second harmonic and fundamental wave of femtosecond Ti:sapphire laser at repetition rate of 1 kHz, the carrier-envelope phase (CEP) passively stabilized pulses with a tunable wavelength from 1.1 to 1.6 μm are obtained with maximum energy of 95 μJ at 1.3 μm under the pump energy of 500 μJ. The CEP jitter of pulses is 108 mrad measured by an f-2f interferometer. This work demonstrates a new way to efficiently generate tunable near-infrared femtosecond laser pulses with self-stabilized CEP.

Climate change can sometimes be reflected in variations in lake levels, thus understanding variations in lake levels and their relationship to climate change plays an important role in studying climate change. In this study, about 10 years of Topex/Poseidon (T/P) altimetric data and 6 years of Jason-1 data were used to compute time series of level variations of six lakes in the Central and East Asia. The study sites were Hongze, La-ang, Ulungur, Khanka, Issyk-kul and Baikal Lakes. Time series of level variations were analyzed by means of the wavelet spectrum for inter-annual (between 2 to 4 years), annual and semiannual signals. Since 2000, water level variations of Issyk-kul, Ulungur and Khanka lakes were larger than those of Baikal and Hongze. Correlations between the NINO3.4 sea surface temperature (SST) and the level variations of the six lakes were analyzed. For Baikal and Khanka Lakes, the correlations were significant (+0.3834 and +0.3334) for 3 - 5 months after the occurrence of ENSO, while the correlation for La-ang Lake was the weakest (< 0.1), indicating that ENSO showed a lag influence on variation in lake levels in the Central and East Asia.

Two new ferrocenylhydrazone-based receptors FcL1 and FcL2 were prepared and the X-ray crystal structure of FcL1 was described. The electrochemical studies reveal that the receptor FcL1 is responsive to Hg2+ and Cr3+, whereas, receptor FcL2 only responsive to Hg2+. The maximum electrochemical shift of FcL1 for Cr3+ is about 56 mV. Copyright © 2009 John Wiley & Sons, Ltd.

A binuclear macroheterocyclic complex Zn2(FcL)2 based on ferrocene-thiocarbazide (FcL) was synthesized. X-ray diffraction analysis shows that it belongs to the monoclinic system P2(1)/n space group, with a = 1.35379(17) nm, b = 2.6026(3) nm, c = 1.8693(2) nm, β = 95.687(2)° and final R indices R = 0.0796 and Rw = 0.2119. Two Zn(II) ions and two FcL ligands form a 22-membered macroheterocycle, further extended to an infinite 1-D helical chain by intermolecular hydrogen bonding. Spectral properties of the title complex and electrochemical properties of the ligand FcL are also discussed.

Detailed theoretical analysis of the working characteristics of the hanging tape torque and the computation of zero position correction in the orientation observation with the gyro-theodolite are made in the paper. The practical data prove that the conclusion is right.

The purpose was to explore the gap between China and the international world in efficiency measurement of hospitals with Data Envelopment Analysis, and to improve the standardization of healthcare efficiency measurement in China. A systematic review was conducted using appropriate search strategies. Studies were included containing DEA approaches regarding general hospital efficiency, published in international literature and in both Chinese and English about Chinese hospitals from January 2004 to October 2014. The results showed that statistical significances were found in indicators such as number of DMUs, percentage of allocative efficiency studies, ratio of studies with multiple years, number of studies with monetary indicators in input and output sets, etc. The statistical insignificance in some indicators such as the number of input and output indicators were also found among China, Europe, USA and others. Some problems were found in current DEA-based hospital efficiency studies in China, such as inappropriate selection of input-output indicators, no bias-correction on efficiency scores, etc. The standardization of DEA methods applied in China’s hospital efficiency research needs to be improved. Chinese researchers should pay more attention to latest international research findings, so as to keep pace with the cutting edge hospital efficiency research.

Summary form only given. We will present theoretical and experimental results of our research on a Traveling Wave Tube (TWT) amplifier using a metamaterial (MTM) structure. MTM structures have unique properties such as high effective permittivity and permeability which can be harnessed in a slow wave structure (SWS) for enabling strong interaction with an electron beam to produce signal gain. The frequency selective properties of the MTM structure make it interesting to suppress parasitic oscillations usually encountered in a high gain amplifier. We will present the compact design of 6 GHz TWT amplifier. A rectangular waveguide is employed in transverse magnetic mode resulting in a strong axial electric field. The hollow waveguide in TM mode operation is treated as magnetic plasma in this work. The enclosed metal walls create effective negative permeability. As the frequency is reduced below the waveguide cut-off, the effective permeability exhibits very large absolute value. This property helps reduce the phase velocity at lower frequencies. A uniaxial electric metamaterial is designed with effective negative permittivity. The structure exhibits double negative permittivity and permeability while inserting the uniaxial electric metamaterial to the magnetic plasma waveguide. The structure therefore has negative refractive index with large absolute value. The phase velocity is reduced to ~0.15c. The calculated values of the on-axis Pierce impedance indicate a strong interaction beam-wave interaction. Cold and hot simulations were both implemented in Particle in Cell (PIC) code namely, CST Particle Studio. These simulations verified the properties of this MTM based TWT amplifier and show > 20 dB signal gain. A cold test structure is currently under fabrication and experimental cold test results will be presented.

It is critical and difficult to involve social behavior factors into the engineering design of road intersections, which will improve the humanism and traffic order of intersections. So, it has great theoretical value and practical significance to integrate the knowledge in traffic behavior research area to identify, describe and simulate the mechanism and impacts of social behaviors on intersection traffic. Based on the analysis of the social complexity of traffic system and the design of traffic behavior decision-making model, this paper presents a framework to identify and describe traffic behavior factors and mechanisms. Through the literature mining on traffic social behavior, related factors and internal and functional mechanism of traffic behaviors, psychological and interactive features of participants are listed as rules in CA model. Then, the CA-based ideal intersection model, participant characteristics model and participant interaction model are designed and integrated to be a behavior-intensive CA model. Some typical intersection scenarios are simulated to verify the theory and methods, which will provide decision-making support for the humanism design of intersections, and reference for similar traffic social issues.

The electromagnetic-bandgap filter described here has a stopband that can be tuned using liquid metal to adjust the spacing of EBG elements. This was demonstrated by shifting the stopband center frequency of the filter from 10.1 GHz to 5.5 GHz. The frequency shift was achieved by pumping liquid metal into fluidic chambers built on the ground plane of the filter, filling in the holes in the ground plane. Although the liquid metal in the current system was manually pumped using a syringe, future filters may use programmable micropumps to achieve the desired tuning between different filter states.

A new type of tunable low-pass filter is demonstrated that uses liquid metal to reconfigure a defected ground structure (DGS). By filling in different DGS lattices with Galinstan liquid metal, the tunable low-pass filter provides tuning of up to eight cutoff frequencies. Measurements of four of the cutoff frequencies show a 62% tuning range while maintaining a stopband of more than 5 GHz.

The present paper is aimed to investigate the effects of pulse electrical stimulation on mutual adhesion of vascular endothelial cell and endothelial progenitor cell (EPC). EPC was induced from periphery blood, labeled with fluorescence dye and then co-cultured with vascular endothelial cell. With a fixed electric voltage and frequency of 5V and 5Hz, respectively, the co-culture system was continually stimulated for 24h under different pulse width, 1, 3, 6 and 9ms. After pulse stimulation, fluorescence intensity of adherent labeled EPC was measured and converted to fluorescence ratio. Compared to that in the control group, fluorescence ratio of 3 ms and 6 ms group were significantly larger, while that in the 9 ms group was lower. The peak fluorescence ratio value was appeared at 6 ms group. It is indicated that suitable pulse electrical stimulation could benefit the adhesion of endothelial cell and EPC. All these results provide a new theoretical basis about why electrical stimulation could contribute to neovascularization.

The environment of the mountainous area is one of important parts in urban ecological and economic system. It has an impact on the stabilization of urban ecological environment. Mentougou District in Beijing, a mountainous area, had abundant mineral resources originally. Many years' exploitation activities made the mineral resources exhausted. It is an inevitable objective law that each mining site has to face. Of course, we know that it brought enormous benefits for the local government and the mine group, while it also had caused tremendous environmental damage. In order to realize the periurban ecological barrier of Beijing, the damaged ecosystem must be restored and the rapid succession of the architecture of plant community should be finished successfully. The paper took the Wangpingcun coal mine as a case study, the estimation models of the biophysical and biochemical parameters of vegetation were established by hyperspectral remote sensing technology. The fresh weight estimation model of vegetation was built based on the vegetation index of R752/R548 by thrice function method. The estimation model of chlorophyll concentration (SPAD) was established through linear four-point interpolation technique. The total nitrogen content estimation model was created based on derivative spectrum among the absorption bands ranging from 350 nm to 2500 nm through the multivariate regression modelling. Based on the construction of above models, the spatial distribution maps of biophysical and biochemical parameters of vegetation were extracted by the parameter mapping and regularities of distribution were revealed. The research results showed that the precisions of above estimation models were very high. The multiple determinant coefficients (R2) of fresh weight and SPAD and the total nitrogen content estimation models of vegetation were 0.883, 0.814 and 0.795 respectively. The spatial distribution maps indicated that the chlorophyll concentration and fresh weight of vegetation around the coal wastes pile were the minimum. The more the SPAD and fresh weight became, the farther the distance away from the coal wastes pile became. The regularity of distribution of the total nitrogen content was completely opposite to the fresh weight and SPAD. It is concluded that estimating biophysical and biochemical parameters of vegetation using hyperspectral remote sensing is completely possible. It has theoretical significance for restoring service function of ecosystem and transforming regional industrial structure.

A high efficiency, tunable, carrier-envelope-phase (CEP) stabilized near-infrared optical parametric amplifier (OPA) is demonstrated with just a single BBO crystal. A white-light continuum produced by a CEP-stabilized laser is seeded into the two stages of the type II OPA system. We achieved a pump-to-signal conversion efficiency of 34% with a single nonlinear crystal. To our knowledge this is the highest conversion efficiency reported in broadband optical parametric amplification, using the two stages. This work demonstrates a compact way to for tunable femtosecond pulses with CEP stabilization.