Inverse synthetic aperture radar (ISAR) imaging of a precessing target, which is a kind of fast spinning target, is faced with migration through range cell when using traditional imaging algorithms. ...Theory of compressed sensing (CS) suggests that exact recovery of an unknown sparse signal with an overwhelming probability can be achieved from very limited number of samples. A cycle shift smoothed L0 algorithm based on CS is proposed in this paper for high-resolution ISAR imaging of precessing targets by exploiting sparse apertures. A precessing cone-shaped target model is built and a 3-D reconstruction method based on multistatic ISAR is proposed. Simulations and electromagnetic computation verify the validity of the proposed method.
Through information sharing, vehicles can know the surrounding road condition information timely in Vehicular Adhoc Networks. To ensure the validity of these messages and the security of vehicles, ...the message authentication, privacy-preserving, and delay problems are three important issues. Although many conditional privacy-preserving authentication schemes have been proposed to ensure secure communication, there still exist some imperfections such as frequent interactions or unlinkability. From this, our paper proposes a novel hierarchical blockchain-assisted authentication scheme to solve these existing issues comprehensively. First, unlinkability is achieved by a dynamic key derivation algorithm. Second, the proposed scheme can reduce correlation processing delay, queuing delay, and deployment costs by adopting hierarchical Vehicle Fog Computing. Third, cross-region authentication is achieved by taking advantage of the properties of blockchain. In addition, we demonstrate our scheme can fulfill the security criteria of the Vehicular Adhoc Network by security analysis. Furthermore, the simulations are carried out to show its availability by using JAVA and NS-3. The findings reveal that the suggested method outperforms earlier schemes in terms of computation cost and communication cost. All in all, making the authentication scheme more efficient and concise is the focus of our future research.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Ball-milling is considered as an economical and simple technology to produce novel engineered materials. The ball-milled microscale zero valent iron/pyrite composite (BM-ZVI/FeS
2
) had been ...synthesized through ball-milling technology and applied for highly efficient sequestration of antimonate (Sb(V)) in aqueous solution. BM-ZVI/FeS
2
exhibited good Sb(V) removal efficiency (≥ 99.18%) at initial concentration less than 100 mg Sb(V)/L. Compared to ball-milled zero valent iron (ZVI) and pyrite (FeS
2
), BM-ZVI/FeS
2
exhibited extremely higher removal efficiency due to the good synergistic adsorption effect. BM-ZVI/FeS
2
showed efficient removal performance at broad pH (2.6–10.6). Moreover, the coexisting anions had negligible inhibition influence on the Sb(V) removal. The antimony mine wastewater can be efficiently remediated by BM-ZVI/FeS
2
, and the residual Sb(V) concentrations (< 0.96 μg/L) can meet the mandatory discharge limit in drinking water (5 μg Sb/L). Experimental and model results demonstrated that endothermic reaction and chemisorption were involved in Sb(V) removal by BM-ZVI/FeS
2
. The XRD and XPS analyses confirmed that the complete corrosion of ZVI occurred on BM-ZVI/FeS
2
after Sb(V) adsorption, resulting in the enhanced Sb(V) sequestration. Mechanism analyses showed that the excellent removal performance of BM-ZVI/FeS
2
was ascribed to the high coverage of iron (hydr)oxide oxidized from ZVI. Because of the advantages of economical cost, high Sb(V) removal capacity and easy availability, BM-ZVI/FeS
2
offers a promising adsorbent for Sb(V) remediation.
The working⁻sleeping cycle strategy used for sensor nodes with limited power supply in wireless sensor networks can effectively save their energy, but also causes opportunistic node connections due ...to the intermittent communication mode, which can affect the reliability of data transmission. To address this problem, a data collection scheme based on opportunistic node connections is proposed to achieve efficient data collection in a network with a mobile sink. In this scheme, the mobile sink first broadcasts a tag message to start a data collection period, and all nodes that receive this message will use the probe message to forward their own source information to the mobile sink. On receiving these probe messages, the mobile sink then constructs an opportunistic connection random graph by analyzing the source information included in them, and calculates the optimal path from itself to each node in this random graph, therefore a spanning tree could be generated with the mobile sink play as the root node, finally, it broadcasts this spanning tree so that each node could obtain an optimal path from itself to the mobile sink to forward the sensing data. In addition, a routing protocol that adapts to different nodes operating statuses is proposed to improve the reliability of data transmission. Simulation results show that the proposed scheme works better concerning the packet delivery rate, energy consumption and network lifetime.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Large scale genomic aberrations including duplication, deletion, translocation, and other structural changes are the cause of a subtype of hereditary genetic disorders and contribute to onset or ...progress of cancer. The current prime editor, PE2, consisting of Cas9-nickase and reverse transcriptase enables efficient editing of genomic deletion and insertion, however, at small scale. Here, we designed a novel prime editor by fusing reverse transcriptase (RT) to nuclease wild-type Cas9 (WT-PE) to edit large genomic fragment. WT-PE system simultaneously introduced a double strand break (DSB) and a single 3' extended flap in the target site. Coupled with paired prime editing guide RNAs (pegRNAs) that have complementary sequences in their 3' terminus while target different genomic regions, WT-PE produced bi-directional prime editing, which enabled efficient and versatile large-scale genome editing, including large fragment deletion up to 16.8 megabase (Mb) pairs and chromosomal translocation. Therefore, our WT-PE system has great potential to model or treat diseases related to large-fragment aberrations.
Owing to the sparsity of the space distribution of point scatterers, compressed sensing (CS) method is successfully applied in inverse synthetic aperture radar (ISAR) imaging. However, in addition to ...sparsity, ISAR images usually exhibit group sparse structure. Here, the authors propose a novel two-dimensional (2D) group primal dual active set with continuation (2DGPDASC) algorithm to recover an ISAR image, which always exhibit 2D group sparse structure. This algorithm is based on the regularised least-squares problem with an ${\rm \ell }^0\left({{\rm \ell }^2} \right)$ℓ0ℓ2 penalty model. At each iteration of the proposed method, it involves solving a least-squares problem on the active set only, and exhibits a fast local convergence within a finite step. Experimental results validate the effectiveness and superiority of the proposed method.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
•Roscovitine alleviates renal functional and histological injuries of diabetic mice.•Roscovitine attenuates renal fibrosis of diabetic mice.•Roscovitine inhibits EMT of tubular cell in diabetic ...mice.•Roscovitine reduces TGF-β1/p38MAPK expression to inhibit EMT in diabetic mice.
Tubulointerstitial fibrosis is the hallmark of diabetic nephropathy, which is the leading cause of end-stage renal disease worldwide. Roscovitine, an inhibitor of Cdks, exhibits anti-fibrosis effects. The present study was aimed to explore the protected role of roscovitine from renal fibrosis of diabetic nephropathy. In vivo study showed that roscovitine treatment significantly ameliorated renal functional and histological injuries in diabetic mice. It was also showed that roscovitine coordinately inhibited the expression of collagen, α-SMA, TGF-β1, and retaining E-cadherin expression. At the cellular level, roscovitine treated HK2 cells cultured with high glucose. It was revealed that roscovitine successfully reduced α-SMA expression and ameliorated the decrease expression of E-cadherin, the two markers of tubular cell EMT. At the molecular level, roscovitine was found to exert this effect through inhibiting the up-regulation of TGF-β1/p38MAPK pathway in high glucose cultured HK2 cells. These study demonstrated a novel mechanism that roscovitine has the anti-fibrosis effects by inhibiting the TGF-β1/p38MAPK pathway in diabetic mice.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Estimation of clutter rank in the reduce-dimension (RD) domain has great importance for RD space-time adaptive processing (STAP) algorithms. In this letter, clutter rank estimation rules of RD STAP ...algorithms for multiple input multiple output (MIMO) radar with different parameters are developed. The accuracy of the proposed rules is verified and the way to design RD MIMO STAP processor under the guidance of the proposed rules is presented.
Research on the fractional order system is becoming more and more popular. Most of the fractional order controller design methods focus on single-input-single-output processes. In this paper, a ...fractional order internal model controller with inverted decoupling is proposed to handle non-integer order two-input-two-output systems with time delay. The fractional order two-input-two-output (FO-TITO) process is decoupled by inverted decoupling method. The fractional order internal model control (IMC) is then used to simplify the tuning process. Because of the complexity of multiple time delay, the condition of FO-TITO process with time delay is discussed. In order to ensure the robustness of the system, a Maximum sensitivity function is used to tune the parameters. Then Lyapunov stability theory is applied to verify the stability of the system. The proposed controller provides ideal performance for both set point-tracking and disturbance rejection and is robust to process gain variations. Numerical results show the performance of the proposed method.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OBVAL, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
High‐resolution inverse synthetic aperture radar (ISAR) imaging can produce electromagnetic images of a target in the range and cross‐range domain. However, to make full use of an ISAR image in ...target detection and recognition, we need to rescale the image in a homogeneous range and cross‐range domain, and further, to estimate the effective rotational velocity (RV) of the target. A precise ISAR image cross‐range scaling method is proposed. A candidate RV is obtained based on the bisection method. Then, the effective rotation angle (RA) between two sequential rescaled images is characterised by the RA between the major axes of the images. These axes are extracted by principle component analysis (PCA). A precise estimation of the RV is obtained through iterative PCA and bisection. Simulated and real data experimental results validate the effectiveness of the proposed method.
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