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With the increasing diversity of social media, the demand for real-time analysis of social networks continues to increase, and research on dynamic community detection has received extensive attention. Existing community detection reviews mostly focus on static community detection and the discussion of related methods, so network evolution analysis cannot be carried out. Besides, the entity data in the community are cross-substitutional and sequential. Therefore, the research status of dynamic community detection is studied, reviewed, and analyzed. First, based on the research background of complex networks, a general research framework for dynamic community detection is proposed. Then, the relevant definitions of dynamic community detection are formally expressed, and the evolution of dynamic communities at the network level and node level is analyzed in detail. According to the difference in architecture and technology, the dynamic community detection methods are summarized and classified. Combined with commonly used data sets, the static community detection algorithm is analyzed qualitatively and quantitatively with evaluation criteria. Finally, the typical application scenarios of community detection are introduced, the main challenges faced by current dynamic community detection research are discussed, and relevant solutions are put forward for dynamic communities, which outlines a clearer and comprehensive research direction for dynamic community detection research field.

Exploring the mechanisms that affect mating pattern with respect to body size has implications for understanding the evolution of sexual selection. Theory predicts that the absence of a relationship between female body size and fecundity, unbiased operational sex ratio, and a short breeding season will lead to random mating by body size in anuran amphibians. We tested these predictions in the Himalayan toad Duttaphrynus himalayanus inhabiting southeastern Tibet. Our study did not detect any correlation between female body size and number of eggs laid, nor was there a significant difference in the sex ratio of toads captured from the breeding site. In addition, the toads were reproductive for only a short period, from late April to early May (typical of an explosively breeding species). As expected, we detected a weak but not significant relationship between body size of amplexing males and females. Our results revealed no apparent size-assortative pairing in the study population of the Himalayan toad and may contribute to an increasing body of literature on mating patterns in relation to body size in animals with indeterminate growth.

The evolution of sexual dimorphism has long fascinated evolutionary biologists and theory suggests that variation in sexual dimorphism is a consequence of selective forces acting differently on morphological traits in males versus females. Here, we analyzed sexual differences in size and shape of the Boulenger’s lazy toad, Scutiger boulengeri, based on the intersex variation pattern of sixteen morphometric traits including body size. The results suggested that sexual dimorphism was apparent in body size and some body shapes (e.g., head length and width, internasal space, interorbital space, diameter of lower arm and tibia width) of this toad. The bigger body size in females may be relevant to fecundity selection, a larger head in males as well as a broader internasal and interorbital space may be subject to male-male competition in combination with ecological selection, and both robust forelimbs and hindlimbs in males may be related to mating and competitive behaviors. These results are discussed with respect to the above selection procedures and possible sex differences in life history traits.

Age determination is crucial for a full understanding of population dynamics. In this context, we studied the age structure of the paddy frog, Fejervarya multistriata, in a population from the central east of China, using a skeletochronological method. The lines of arrested growth in the phalanges were distinct, and each line was assumed to represent one year of age. Ages ranged between one and four years for adult males and two and four years for adult females. No significant difference was observed in the mean adult age between the sexes. In addition, a significant relationship between age and body size within each sex was detected. Results of ANCOVA analysis suggested a significant difference in body size between sexes when the effect of age was removed. The von-Bertalanffy model showed that females had a larger asymptotic body size than males, and the growth rate of females was higher than that of males. Therefore, the growth rate is a major factor underlying body size patterns in both sexes of F. multistriata in the study population.

The polymeric immunoglobulin receptor (pIgR) is an important molecule in the mucosal immunity of teleosts. Previous studies have shown that pIgR can bind and transport polymeric immunoglobulins (pIgs), but few studies have focused on the binding of teleost pIgR to bacteria. In this study, we identified a gene encoding pIgR in largemouth bass (Micropterus salmoides). The pIgR gene contained two Ig-like domains (ILDs), which were homologous to ILD1 and ILD5 of mammalian pIgR. Our results showed that largemouth bass pIgR-ILD could combine with IgM. Moreover, we also found that largemouth bass pIgR-ILD could bind to Aeromonas hydrophila and Micrococcus luteus. Further analysis showed that largemouth bass pIgR-ILD could also combine with lipopolysaccharide (LPS), peptidoglycan (PGN) and various saccharides, and reduced binding to bacteria was observed with LPS and PGN treatment, indicating that largemouth bass pIgR could bind to bacteria to prevent infection and that saccharide binding is an important interaction mechanism between pIgR and bacteria. These results collectively demonstrated that largemouth bass pIgR not only combines with IgM but also binds to bacteria by various saccharides.

The characterization method of aging properties is of great significance for the study of aging degree of polymer materials, including the rule and mechanism of aging, as well as the influence of environmental factors on aging. The research of these methods plays an important role in the development of new experimental technology and testing methods, the improvement of material production technology, the development of special materials, and the design of new materials according to specified properties. Among them, the characterization method of aging performance is mainly realized by mechanical property analysis. The changes of mechanical properties of polymer materials during aging mainly include the changes of impact strength and bending strength of plastics. Through the study of the mechanical property test method after the artificial accelerated aging of the non-metallic low-voltage metering box shell material, the corresponding technology and standards are provided for the quality control of the equipment in the field of smart grid measurement.

In this study, the stability of non-metallic low-pressure tank shell material in typical environment is verified by analyzing the aging process of measuring equipment in typical environment. The operation and failure mechanism of the metering equipment in typical environment are analyzed to ensure that the metering equipment can still work effectively in typical environment and ensure the accuracy and reliability of electric energy metering. By analyzing the impact strength, bending strength and weather resistance of the shell material of non-metallic low-pressure measuring box after aging, the performance of the material after aging is evaluated.

Many smart electricity meters work in different nonideal environments. The complexity of the working environment often leads to the difference between the measurement error of electricity meters and the ideal conditions. In this paper, BP neural network is improved to make it suitable for error analysis of intelligent electricity meter. By identifying, processing, analyzing and integrating a large number of experimental data, the error model of smart electricity meter is established. Then the internal relationship between various stress factors and the error of electricity meter is revealed from the data level. This method can accurately predict the error of electricity meters under certain conditions and lay a foundation for error correction of smart electricity meters in the future. In this paper, the realization process of the method is briefly described through simulation experiments, and the feasibility, rationality and reliability of the method are verified.

The quality of smart meters directly affects the stability, security and economy of information gather system and power grid. This paper proposes a comprehensive quality evaluation method of smart meters based on AHP-Critic theory. In this method, firstly, the hierarchy of AHP is established to determine the contents of target layer, rule layer and scheme layer; secondly, the judgment matrix is constructed to calculate the hierarchical single ranking value and carry out consistency test; thirdly, the objective weight of rule layer is calculated by using Critic theory; finally, the comprehensive weight of rule layer is obtained by combining AHP and Critic, and the hierarchical total ranking of target layer to scheme layer is calculated. The experimental analysis takes three types of smart meters as evaluation objects, and the results effectively evaluate the quality of each meter.

With the rapid development of satellite navigation technology, the application fields of GNSS receivers are also extending. In various military and civil application scenarios, the complex electromagnetic environment will affect the performance of the GNSS receivers, and even make receivers work improperly. Therefore, it is important to test the performance of the GNSS receivers in the complex electromagnetic environment by adaptability test. Based on the analysis of the concept of complex electromagnetic environment, this paper discusses key issues in complex electromagnetic environment adaptability test of GNSS receivers, such as the construction and evaluation of complex electromagnetic environment, adaptability test procedures, test evaluation method, and so on. The research achievements may provide technique reference for the further research on the adaptability test of GNSS receiver in complex electromagnetic environment.

One of the key technical research points in the field of smart grid measurement is to make a breakthrough in the detection and evaluation of high availability materials in intelligent measurement equipment. The comprehensive cross-action of multi-environmental stress brings a lot of data, how to find the key parameters in it, and how to analyze the complex environment into the characteristic combination of multiple single environmental factors, and the mathematical model of nonlinear evolution and service life of material aging based on the characteristic expression of the combination, all of the above are the key points and difficulties of the research. On the basis of the service life model, the research on differential protection measures and the study of life evaluation technology for smart grid measurement equipment can enable the equipment to realize wide-area application and high availability under more harsh conditions, which is one of the key points to improve the quality control in NQI system.

The optical power distribution and the symmetry of the lens components are two important attributes that decide the ultimate lens performance and characteristics. Lens form parameters W and S are the key criteria describing the two attributes mentioned above. Lens components with smaller W and S will have a good nature of aberration balance and perform well in providing good image quality. Applying the Gaussian brackets, the two lens form parameters and the Seidel Aberration Coefficients are reconstructed. An initial lens structure can be analytically described by simultaneous equations of Seidel Aberration Coefficients and third-order aberration theory. Adding the constraints of parameters W and S in the solving process, a solution with a proper image quality and aberration distribution is achieved. The optical properties and image quality of the system based on the parameters W and S are also analyzed in this article. In the method, the aberration distribution can be controlled to some extent in the beginning of design, so that we can reduce some workload of optimization later.

A stationary phase method and ambiguity function (AF) method were used to conduct an analytical study of a modulation transfer function (MTF). From the perspective of mathematic models, there was a double integral relationship between the MTF and system wave aberrations. Based on the stationary phase and AF methods, the wave aberration term in the MTF expression was analytically discussed to achieve an aberration function derivation and extreme point analysis, thereby obtaining the analytical expressions of an every field-of-view (FOV) MTF and defocusing distance (i.e., the deviation of an MTF optimal imaging plane from an axial imaging plane) in the full FOV of an optical system. From the obtained image quality evaluation function, the defocusing distance and system image quality could be effectively controlled in a full FOV, which was verified using the examples.