Due to the lack of corresponding scientific evaluation standards and effective evaluation methods for the overall performance of the Internet of Things system, the Internet of Things industry and the ...market are in a chaotic state, and the quality of various products is uneven. It is difficult for users to select a more suitable application system, which seriously restricts the development process of the industrialization of Internet of Things technology. Therefore, it is very necessary for us to conduct research on the performance evaluation methods of IoT systems. In this paper, the performance of IoT system is selected as the performance evaluation index of the system, and the evaluation system is constructed. The performance evaluation method of the Internet of Things system based on the cloud model is proposed. The comprehensive evaluation of the reliability of the IoT system for the cloud model will be based on the AHP. Based on the combination of attribute decision-making methods, a comprehensive evaluation method based on indicators is proposed, and the system’s indicator model is established. The reliability of the Internet of Things system can be comprehensively evaluated by the value of the indicators. Secondly, the probability density function of tracking error is studied, and its optimal probability density distribution is given by optimal control. Based on the optimal probability density distribution, the performance evaluation index of the system is constructed. In order to compare the current probability density function with the reference probability density function, the tracking error function is first vector, then the performance evaluation index is constructed by gray correlation, and the general steps of performance evaluation based on this index are given. Finally, the effectiveness of the proposed system performance evaluation algorithm is verified by simulation comparison. The data processing and experimental simulation are used to achieve the purpose of evaluating the performance of the Internet of Things system.
Hydrophobic interactions are widely applied in diverse fields, yet the effect of the degree of hydrophobicity on the interactions between hydrophobic surfaces is still unaddressed, limiting the ...development of functional hydrophobic surfaces. In this study, the interfacial interactions and configuration of hydrophobic chains on surfaces with ranging hydrophobicity are surveyed by surface forces apparatus. Our findings revealed that with partial hydrophobicity, a long-range electrical double-layer repulsive force pertains between surfaces, while between fully hydrophobized surfaces, only steric hindrance is observed, and the hydrophobic chains maintain configuration even after long time compression. Our findings provide useful implications for understanding hydrophobic interactions.
Introduction. The development of combinatorial adjuvants is a promising strategy to boost vaccination efficiency. Accumulating evidence indicates that manganese exerts strong immunocompetence and ...will become an enormous potential adjuvant. Here, we described a novel combination of Mn2+ plus aluminum hydroxide (AH) adjuvant that significantly exhibited the synergistic immune effect. Methodology. Initially, IsdB3 proteins as the immune-dominant fragment of IsdB proteins derived from Staphylococcus aureus (S. aureus) were prepared. IsdB3 proteins were identified by western blotting. Furthermore, we immunized C57/B6 mice with IsdB3 proteins plus Mn2+ and AH adjuvant. After the second immunization, the proliferation of lymphocytes was measured by the cell counting kit-8 (CCK-8) and the level of IFN-γ, IL-4, IL-10, and IL-17 cytokine from spleen lymphocytes in mice and generation of the antibodies against IsdB3 in serum was detected with ELISA, and the protective immune response was assessed through S. aureus challenge. Results. IsdB3 proteins plus Mn2+ and AH obviously stimulated the proliferation of spleen lymphocytes and increased the secretion of IFN-γ, IL-4, IL-10, and IL-17 cytokine in mice, markedly enhanced the generation of the antibodies against IsdB3 in serum, observably decreased bacterial load in organs, and greatly improved the survival rate of mice. Conclusion. These data showed that the combination of Mn2+ and AH significantly acted a synergistic effect, reinforced the immunogenicity of IsdB3, and offered a new strategy to increase vaccine efficiency.
A symmetric graphene plasmon waveguide (SGPWG) is proposed here to achieve excellent subwavelength waveguiding performance of mid-infrared waves. The modal properties of the fundamental graphene ...plasmon mode are investigated by use of the finite element method. Due to the naturally rounded tips, the plasmon mode in SGPWG could achieve a normalized mode field area of ~10−5 (or less) and a figure of merit over 400 by tuning the key geometric structure parameters and the chemical potential of graphene. In addition, results show that the modal performance of SGPWG seems to improve over its circular counterparts. Besides the modal properties, crosstalk analysis indicates that the proposed waveguide exhibits extremely low crosstalk, even at a separation distance of 64 nm. Due to these excellent characteristics, the proposed waveguide has promising applications in ultra-compact integrated photonic components and other intriguing nanoscale devices.
With the development of aviation technology and the scramble for air supremacy is becoming increasingly fierce, people put forward higher requirements on the performance of the fighter. The thrust ...vector nozzle based on flow control has many advantages compared with the traditional mechanical control method, in the thrust vector technology, the thrust loss is low, it can also be applied in subsonic speed. Thrust vector technology has a wider application background. In this paper, the basic principle of counter current thrust vector technology is explained firstly, then the simplified derivation of the formula and the definition of related parameters are derived by the control body analysis. And fluent software is used to simulate the existing experimental model, the obtained numerical results are compared with the experimental data available in the literature, verification proves that the numerical method is feasible. Then change the Maher number of outflow size of vector analysis to effect change. Finally, for thrust vector effect is not obvious under the Maher problem, the design provides a method for vacuum reverse two secondary channel, and its feasibility by using the method of numerical analysis, the vacuum in the two channel is increased, and the thrust vector angle can reach to 18.1 degrees from 1.7 degrees, an increase of about 10 times.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
Colorectal cancer (CRC) is the third most prevalent malignant tumor worldwide and the second leading cause of cancer-related death. This study aimed at reporting the disease burden of CRC in China ...from 1990 to 2019 and predicting the trend of mortality burden over the next 10 years.
The age-period-cohort model was implemented to analyze the trends of mortality from CRC in China from 1990 to 2019, and the autoregressive integrated moving average (ARIMA) model was used to predict the trends of CRC incidence and mortality from 2020 to 2029.
From 1990 to 2019, the incidence of CRC in China increased from 105,911 cases (95% uncertainty interval UI: 93,808-119,021) to 607,900 cases (95% UI: 521,805-708,420). The age-standardized incidence rate increased from 12.52 per 100,000 (95% UI: 11.15-14.03) to 30.55 per 100,000 (95% UI: 26.37-35.5), with an estimated annual percentage change (EAPC) of 3.66 (95% confidence interval CI: 3.37-3.95), showing an upward trend. The age-standardized mortality rate increased from 10.18 per 100,000 (95% UI: 9.03-11.37) to 13.86 per 100,000 (95% UI: 11.92-16.01), with an EAPC of 1.39 (95% CI: 1.14-1.63), also showing an upward trend. The age group with the highest incidence and mortality in 2019 was 65-69 years old for both sexes, and the age group with the highest mortality was 70-74 years old. Males had higher relative risks of incidence and mortality than females. Low-calcium diet was the risk factor for both sexes and females alone in 1990, while low-milk diet was the risk factor in 2019; however, smoking remained the risk factor for males. The ARIMA model predicted an increase in both disease and mortality burden of CRC over the next 10 years.
The disease and mortality burden of CRC in China showed an overall upward trend from 1990 to 2019, with higher burden in males than females, and the situation remains extremely severe in the next decade.
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(GYbZ) materials deposited on irregular substrates for improving new thermal barrier coatings. Three-point ...bending fracture characteristics of freestanding GYbZ coating prepared by supersonic plasma sprayed (SPS) technique were investigated with the help of digital image correlation technique. The cracking time, crack propagation path, and mechanical properties of GYbZ coating were obtained. Meanwhile, the X-ray computed tomography technique was introduced to scan the microstructure of freestanding GYbZ coatings, which are used to establish three-dimensional (3D) finite element model by using the Avizo software. The brittle cracking criterion was applied to describe the bending fracture process of GYbZ coatings. The critical cracking strain was estimated as 0.36%±0.03% by repeatedly comparing the difference between the experimental and simulated curves. The results would be extended to predict the dangerous region and failure mechanisms of GYbZ coatings deposited on irregular substrate during finite element simulations.
Fourier ptychographic microscopy (FPM) is an enabling quantitative phase imaging technique with both high-resolution (HR) and wide field-of-view (FOV), which can surpass the diffraction limit of the ...objective lens by employing an LED array to provide angular-varying illumination. The precise illumination angles are critical to ensure exact reconstruction, while it's difficult to separate actual positional parameters in conventional algorithmic self-calibration approaches due to the mixing of multiple systematic error sources. In this paper, we report a pupil-function-based strategy for independently calibrating the position of LED array. We first deduce the relationship between positional deviation and pupil function in the Fourier domain through a common iterative route. Then, we propose a judgment criterion to determine the misalignment situations, which is based on the arrangement of LED array in the spatial domain. By combining the mapping of complex domains, we can accurately solve the spatial positional parameters concerning the LED array through a boundary-finding scheme. Relevant simulations and experiments demonstrate the proposed method is accessible to precisely correct the positional misalignment of LED array. The approach based on the pupil function is expected to provide valuable insights for precise position correction in the field of microscopy.
Extensive evaluation on a large number of word embedding models for language processing applications is conducted in this work. First, we introduce popular word embedding models and discuss desired ...properties of word models and evaluation methods (or evaluators). Then, we categorize evaluators into intrinsic and extrinsic two types. Intrinsic evaluators test the quality of a representation independent of specific natural language processing tasks while extrinsic evaluators use word embeddings as input features to a downstream task and measure changes in performance metrics specific to that task. We report experimental results of intrinsic and extrinsic evaluators on six word embedding models. It is shown that different evaluators focus on different aspects of word models, and some are more correlated with natural language processing tasks. Finally, we adopt correlation analysis to study performance consistency of extrinsic and intrinsic evaluators.
•The frequency characteristics of SRF-PLL, DSOGI-FLL and DDSRF-PLL are modeled respectively.•The impedances of the inverter are modeled with the PLLs displayed, and the influences of different PLLs ...on the inverter impedance are compared.•The effects of the PLLs on the stability of the system are studied to discuss the stability boundary conditions of the system.•Based on the equivalent impedance model of the PLL, the optimized design method of the PLL is proposed to improve the system stability.
For grid-connected inverters, phase-locked loop (PLL) is an indispensable part for grid currents to track grid voltages. Hence, PLL will have a nonnegligible effect on the stability of the interconnected system involving a grid-connected inverter and a power grid. Therefore, it is necessary to model the frequency characteristic of PLL and analyze its effect on the system stability. In this paper, three kinds of the commonly used PLL circuits are firstly employed to model and compare their frequency characteristics. Second, the impedances of the inverter are modeled with the equivalent impedance model of PLL displayed, and the influences of different PLLs on the impedance characteristics of the inverter are compared. Then, the effects of PLLs on the stability of the interconnected system are studied to discuss the stability boundary conditions of the system. Based on the equivalent impedance model of the PLL, the optimized design method of the PLL is proposed from the perspective of optimizing the inverter impedance characteristics to improve the system stability. Finally, the simulation and experimental results are presented to verify the correctness of the PLL frequency characteristics and the inverter impedance models, and confirm the effectiveness of the optimized design method.
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