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Rotational inertial navigation system (RINS) could improve the navigation performance by rotating the IMU around gimbals, and the structure and function of the dual-axis RINS also help realize the process of self-calibration. However, the gyro–accelerometer asynchronous time is not considered in current studies. Coupled into the navigation error, the gyro–accelerometer asynchronous time can lead to velocity accuracy decline during the process of rotation. Therefore, the modeling and calibration of the gyro–accelerometer asynchronous time would enhance the systemic reliability. In this article, in order to solve the abovementioned problem: 1) we model the gyro–accelerometer asynchronous time and perform an error analysis of gyro–accelerometer asynchronous time; 2) we propose a compensation method of the outer lever arm to improve the accuracy of the observed velocity and position; and 3) we derive a continuous linear 40-D RINS error model considering the abovementioned two error parameters compared with the traditional method, the PWCS method, and the SVD method is utilized to provide the observability degrees of the proposed state during the self-calibration process. Experimental results illustrated that the proposed method can improve the accuracy in the long-endurance navigation.

Radish (Raphanus sativus L.) belongs to the family Brassicaceae. The Yunnan red radish variety contains relatively large amounts of anthocyanins, making them important raw materials for producing edible red pigment. However, the genetic mechanism underlying this pigmentation has not been fully characterized. Here, the radish inbred line YAAS-WR1 (white root skin and white root flesh) was crossed with the inbred line YAAS-RR1 (red root skin and red root flesh) to produce F1, F2, BC1P1, and BC1P2 populations. Genetic analyses revealed that the pigmented/non-pigmented and purple/red traits were controlled by two genetic loci. The F2 population and the specific-locus amplified fragment sequencing (SLAF-seq) technique were used to construct a high-density genetic map (1230.16 cM), which contained 4032 markers distributed in nine linkage groups, with a mean distance between markers of 0.31 cM. Additionally, two quantitative trait loci (QAC1 and QAC2) considerably affecting radish pigmentation were detected. A bioinformatics analysis of the QAC1 region identified 58 predicted protein-coding genes. Of these, RsF3′H, which is related to anthocyanin biosynthesis, was revealed as a likely candidate gene responsible for the purple/red trait. The results were further verified by analyzing gene structure and expression. Regarding QAC2, RsMYB1.3 was determined to be a likely candidate gene important for the pigmented/non-pigmented trait, with a 4-bp insertion in the first exon that introduced a premature termination codon in the YAAS-WR1 sequence. Assays demonstrated that RsMYB1.3 interacted with RsTT8 and activated RsTT8 and RsUFGT expression. These findings may help clarify the complex regulatory mechanism underlying radish anthocyanin synthesis. Furthermore, this study’s results may be relevant for the molecular breeding of radish to improve the anthocyanin content and appearance of the taproots.

Recently, with the improvement of attack technology and computational capability, how to meet the security application of streaming media data has become a significant issue, especially for systems with a high standard of security. This paper presents a real-time authentication scheme for P2P streaming media transmission system, which can at least meet the application of identity authentication, tamper location, and error retransmission. We first tailor and employ off-the-shelf algorithms to propose two types of watermarking algorithms (the Feature Watermarker and the Identity Watermarker). Then, the sliding window is employed to group and provision the above two types of watermarks in the overall authentication scheme. Several metrics are employed to indicate our watermarking meets the application of invisibility and has a very low false alarm rate and missing alarm rate after computing and choosing viable thresholds. Moreover, we sketch an “Attack List” aiming at detecting and deal with malicious behaviors effectively, including two types of attacks which is irresistible for the common watermarking algorithms (Re-embedded attack and Destruction of watermark). The delay in transmission turns out to be acceptable by reasonably tailoring crucial parameters.

In-motion alignment of Strapdown Inertial Navigation Systems (SINS) without any geodetic-frame observations is one of the toughest challenges for odometer aided navigation system. It is difficult to obtain an accurate attitude within a short time using coarse alignment under intense maneuvering condition, so one of the main obstacles during in-motion alignment for SINS/OD is to estimate an accurate attitude during fine alignment process under large azimuth misalignment angle. However, most current in-motion alignment methods were based on linear error model. In this paper, an OD aided in-motion alignment method based on backtracking scheme for large misalignment angles is proposed. Three improvements were made as the following: (1) A continuous nonlinear 16-dimensional (16D) SINS/OD error model is derived. (2) We proposed a backtracking-based Extended Kalman filter (EKF) and (3) a strict reverse navigation method is utilized in the backward process. Experimental results illustrated that the proposed method can autonomously improve the estimated attitude accuracy under the condition of large misalignment angle.

In this paper, the transient interaction integral method (IEIM) is established to obtain the transient thermal stress intensity factors (TSIFs) in order to study the fracture problems of nonhomogeneous materials under thermal shock loading. The transient temperature field is evaluated by using the finite difference method and the finite element method. The TSIFs of nonhomogeneous materials with multiple cracks are analysed, then the mixed-mode TSIFs of nonhomogeneous materials with different positions are discussed. The results of this study have shown that the current approach is applicable to obtain fracture parameters of nonhomogeneous materials with multiple cracks efficiently, which can be used as a significant reference for the engineering application of nonhomogeneous materials.

Strapdown inertial navigation system (SINS) based vehicle weapon system increases great significance in land navigation. In order to obtain considerable navigation performance, SINS based integrated navigation is required to implemented. However, the popular aided sensor such as Global-Positioning-System (GPS) is not regarded as autonomous sensor. The autonomous sensor such as odometer can be also damaged in practical applications. In this paper, we utilize non-holonomic constraints (NHC) to aid SINS without external sensors. The measurements of NHC include zero lateral velocity and zero vertical velocity in vehicle orthogonal reference frame. Then, the close-loop Kalman filter can be implemented for SINS/NHC integrated navigation. The simulation results show that the SINS/NHC integrated navigation can estimate all the error states with specific movements. Moreover, SINS/NHC can achieve considerable position navigation performance. Therefore, the proposed method can realize autonomous land navigation without external sensors.

A significant issue of land vehicle navigation is in-motion attitude alignment of the odometer (OD)-aided strapdown inertial navigation system (SINS). The consecutive OD outliers can occur due to sudden wheel slipping and skidding while vehicle maneuvering. They seriously reduce the robustness and precision of attitude alignment. In this paper, we investigate a robust in-motion attitude alignment method for the OD-aided SINS. The method consists of in-motion coarse alignment and in-motion fine alignment. In the in-motion coarse alignment process, we developed Huber's M-estimation and integral formula based robust Kalman filter (HRKF/IF-CA), which can restrain the interference of consecutive OD outliers on reconstructed observation vectors. Thus, HRKF/IF-CA can contribute to better coarse attitude results. The next process is in-motion fine alignment. Under the popular repeated backtracking scheme, we investigate HRKF based fine alignment (HRKF-FA) with the SINS/OD summed measurement model. HRKF-FA can refine attitude alignment and restrain the interference of consecutive OD outliers simultaneously. Finally, the proposed method is evaluated by simulation and vehicle test. The attitude alignment results show that this method can achieve reasonable attitude results, and the interference of consecutive OD outliers caused by sudden wheel slipping and skidding can be greatly restrained.

Key message AtWRKY53 is an early factor in drought response and activated expression of AtWRKY53 reg- ulates stomatal movement via reduction of H2O2 con- tent and promotion of starch metabolism in guard cells. Abstract Drought is one of the most serious environ- mental factors limiting the productivity of agricultural crops worldwide. However, the mechanisms underlying drought tolerance in plants remain unclear. AtWRKY53 belongs to the group III of WRKY transcription factors. In this study, we observed both the mRNA and protein products of this gene are rapidly induced under drought conditions. Phenotypic analysis showed AtWRKY53 over- expression lines were hypersensitive to drought stress compared with Col-0 plants. The results of stomatal movement assays and abscisic acid (ABA) content detec- tion indicated that the impaired stomatal closure of 53OV lines was independent of ABA. Further analysis found that WRKY53 regulated stomatal movement via reducing the H2O2 content and promoting the starch metabolism in guard cells. The results of quantitative real-time reverse transcriptase PCR showed that the expression levels of CAT2, CAT3 and QQS were up-regulated in 53OV lines. Chromatin immunoprecipitation assays demonstrated that AtWRKY53 can directly bind to the QQS promoter se- quences, thus led to increased starch metabolism. In sum- mary, our results indicated that the activated expression of AtWRKY53 inhibited stomatal closure by reducing H2O2 content and facilitated stomatal opening by promoting starch degradation.

Considering the key factors that affect the precision of strapdown inertial navigation system (SINS) and odometer integrated navigation system, an on-line calibration method based on Kalman filter aided by odometer is proposed. Dead reckoning (DR) algorithm and DR error model including odometer scale factor and odometer installation errors are given. Based on the error model, a closed-loop Kalman filter is designed to estimate odometer scale factor error, odometer installation errors, gyroscope drifts and accelerometer biases, and then improve the horizontal position precision. Finally, the simulation of SINS/odometer integrated navigation is carried out. Correlated results show that current parameters including odometer scale factor and odometer installation can be estimated on the base of former parameters, and compared with the horizontal position calculated by dead reckoning algorithm, the proposing method exerts a higher horizontal position precision, which sufficiently verifies the validity of proposing method.

This paper introduces several test methods of characteristics of alarm indicator lights which can be used in the medical alarm system to verify the compliance of YY 0709-2009. These methods include the direct measurement of the pulse current supply of the alarm signals, image analysing of a video and reception by photoelectric sensor. After the comparation of the advantages and disadvantages among these methods, this paper proposes a new method of signal reception. This method which used a silicon photocell as the sensor with light filter in its front, and amplified circuit in the output end then used an oscillograph as the reviewer, has resolved the testing difficulties of the flashing signal simulating by LCD, and can be applied to test the alarm indicator lights in any medical electrical equipment.

Rice Blast is one of the most serious rice diseases and caused great yield losses every year in the world. It had been proved that using resistant rice varieties would be the most effective way to control this disease; therefore, mining the resistant genes might be important foundational work in the breeding program. In the present study, we identified the existence of the Pi1 gene among the tested 173 landraces collected from Yunnan Province by using the SSR marker MRG4766. The results showed that the Pi1 gene was found in 64 landraces, accounting for 36.99% in total of 173 landraces. 33 of 102 indica landraces (32.35%) and 31 of 71 japonica landraces (43.66%) both contained Pi1 gene. The landraces harboring the Pi1 gene were distributed in 29 counties of 11 prefectures in Yunnan province. The distribution frequency of Pi1 gene was higher in paddy-upland rice region in South margin of Yunnan (41.03%) than that of in single and or double indica cropping region in south of Yunnan (32.69%). The distribution frequency of Pi1 gene was 35.29% in single indica and or japonica cropping region in center of Yunnan, 35.29% in japonica cropping region in northeast of Yunnan and 33.33% in japonica cropping region in northwest highland of Yunnan.