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In multiple sources jointly indoor positioning context, in the offline phase, it is easier to obtain enough sample features from multiple sources to form multiple source domains, but we have difficulties in obtaining enough sample features in real positioning phase due to sensors fault or changing environments, thus leading to the missing data in a target domain. How to efficiently transfer the knowledge from the source domains to the target domain is the key issue for high accurate sensing. To address the above challenge, we propose a hybrid domains transfer learning (HDTL) (i.e., transfer knowledge between source domains and the single target domain) for high accurate target positioning. Specifically, HDTL first divide the multiple source domains into homogeneous and heterogeneous feature according to the single target domain; then we can calculate the mapping from the homogeneous feature to the heterogeneous feature in the source domains by using shared homogeneous knowledge of the source domain and target domain as a bridge. Next, we can complement heterogeneous data in the target domain by using this mapping in order to guarantee that the features in the source domains and target domain exist in a common homogeneous space. Finally, the location of the target can be calculated in this new feature space. HDTL can localize targets accurately in presence of sensors faults by resorting to the transfer knowledge from the source domains, and is thus superior to some existing transfer learning algorithms. The experimental results show that HDTL can acquire better accuracy in multiple source jointly positioning environments as compared with some existing stand-alone positioning environments.

Cytochrome P450 monooxygenases (CYPs) play essential physiological functions in insects. CYP303A1 is highly conserved in insect species studied to date, and shows an indispensable role for adult eclosion in both Locusta migratoria and Drosophila melanogaster. However, how CYP303A1 is regulated to control insect developmental processes remains uninvestigated. In this study, we discovered functional binding sites for miR‐184 in the coding sequence of LmCYP303A1. The luciferase reporter assay showed that miR‐184 could target LmCYP303A1 and regulate its expression in vitro. Furthermore, overexpression of miR‐184 through microinjection of agomir to locusts reduced the transcripts of LmCYP303A1 and led to abnormal molting, which is similar to the phenotype of silencing LmCYP303A1 by direct injection of dsLmCYP303A1 to locusts. Meanwhile, down‐regulation of miR‐184 by injection of antagomir increased the LmCYP303A1 transcript and caused molting defects. These findings suggested that miR‐184 could target LmCYP303A1 to regulate the molting process in L. migratoria, which might be considered as a novel target for pest control. [ABSTRACT FROM AUTHOR]

The minimum variance distortionless response (MVDR) algorithm is affected by the desired signal (DS) power even if all signals are uncorrelated with each other when the received array data contains the DS. Under the assumption that all signals are independent with each other, this paper analyses the influence of the DS power on the output DS power and the output power of the interference plus noise at first. Then, it analyses the change of the output signal-to-interference-plus-noise ratio (SINR) and its convergence rate with the impact of the DS power. The analysis shows that the output SINR increases with greater DS power within a certain range. However, for the DS power large enough, the ability of the interference suppression would be weaken, which results in an unchanged output SINR no whatever how large the DS power. Moreover, the output SINR suffers from slower convergence rate for larger DS power. The simulations validate the effectiveness of the analysis. [ABSTRACT FROM AUTHOR]

In order to obtain a stable beam pattern and further improve the performance of adaptive beamforming for polarization sensitive array, a Quaternion-Amplitude and Phase Estimation (Q-APES) algorithm is presented for polarization- space adaptive filtering in the paper. First, the quaternion signal model is given and the inherent orthogonal structure of the two component signal output of each sensor has been kept well by using the quaternion signal model. It is obvious that the quaternion signal model is more suitable for two component vector sensor array signal processing than the conventional long vector signal model which is based on the complex number. Second, the conventional APES algorithm for spatial domain filtering has been expanded to the polarization-space adaptive beamforming. The proposed Q-APES algorithm is derived theoretically and the quaternion optimal weight vector is obtained following. Finally, computer simulation results are shown to verify the correctness of the proposed algorithm. The results indicate that Q-APES algorithm can achieve a better filtering performance than the existing Q-MVDR algorithm under the circumstances of strong desired signal power or low sampling snapshot numbers. Moreover, Q-APES algorithm can also perform well even if the incident interference signals are fully correlated with the desired signal. [ABSTRACT FROM AUTHOR]

Internet of Things or cyber-physical systems provide a new challenge for formal modeling methods related to the aspect of physical elements such as location and time. Recently, this paper introduced a specification language called STeC to stress the spatio-temporal consistency for real-time systems. The operational and denotational semantics of and tool set related to this language have been given. The aim of this paper was to establish a STeC to Stateflow automatic transformation system and to propose a simulation and verification approach based on this transformation system. It firstly gave a formal model for an object system in STeC language, and then set up a real-time monitoring simulation model using Simulink. After that, it presented a verification approach for the system safety property based on Checkmate. Finally, it gave a case about Jinghu Gaotie (high speed train) running timetable to show that the proposed approach is effect and usable. [ABSTRACT FROM AUTHOR]

To analyze quality standards of cattle bile and sheep bile, and to discuss the related problems in the standards. The results showed that physical forms of the related medicinal materials of cattle bile and sheep bile were chaotic, and the technical methods adopted in the quality standards were generally backward. In addition, there were still problems that some medicinal material standards lacked necessary test items, which were especially obvious in the relevant medicinal material standards of sheep bile and brought difficulties to quality evaluation and control. We suggest that physical forms of cattle bile and sheep bile in quality standards should be determined, and inspection items should be completed. Based on mainstream analytical technology, some technical methods of these standards should be improved.

Taking three sand-fixing plantations Hedysarum scoparium and Calligonum mongolicum, Haloxylon ammodendron on the oasis verges in northeast Ulanbuhe desert irrigated by Huanghe River as test objects, the multi-species and multi-scale patterns and the species associations of the plantations were investigated by contiguous quadrats transects method, with the natural vegetation nearby as the control. The results showed that 74.29% of the natural vegetation was dominated by single species pattern of Artemisia ordosica, and 24. 99% was dominated by single species pattern of Nitraria tangutorum. The sand-fixing plantations gradually became close-to-natural vegetation. Compared with natural vegetation, the sand-fixing plantations had higher pattern intensity, and played important role in sand-fixing and in accelerating the regeneration and succession of natural sand-fixing plants. However, with the succession, artificially planted shrubs would decline, while natural plants would be dominant. Therefore, it should be better to make use of the native dominated species in sand-fixing engineering. Under the almost same conditions, pattern scale was highly correlated with the characters and the associations of dominated species. The species association was correlated with the patch scale and species composition, as well as the species contribution to the patch.