GNSS receiver autonomous integrity monitoring(RAIM)algorithm based on robust estimation

Integrity is significant for safety-of-life applications. Receiver autonomous integrity monitoring（RAIM） has been developed to provide integrity service for civil aviation. At first,the conventional RAIM algorithm is only suitable for single fault detection, single GNSS constellation. However, multiple satellite failure should be considered when more than one satellite navigation system are adopted. To detect and exclude multi-fault, most current algorithms perform an iteration procedure considering all possible fault model which lead to heavy computation burden. An alternative RAIM is presented in this paper based on multiple satellite constellations（for example, GPS and Bei Dou（BDS） etc.） and robust estimation for multi-fault detection and exclusion, which can not only detect multi-failures,but also control the influences of near failure observation. Besides, the RAIM algorithm based on robust estimation is more efficient than the current RAIM algorithm for multiple constellation and multiple faults. Finally, the algorithm is tested by GPS/Bei Dou data.

Self-organizing strategy design and validation forintegrated air-ground detection swarm

A self-organized integrated air-ground detection swarmis tentatively applied to achieve reentry vehicle landing detection,such as searching and rescuing a manned spaceship. The detectionswarm consists of multiple unmanned aerial vehicles （UAVs）and unmanned ground vehicles （UGVs）. The UAVs can accessa detected object quickly for high mobility, while the UGVs cancomprehensively investigate the object due to the variety of carriedequipment. In addition, the integrated air-ground detectionswarm is capable of detecting from the ground and the air simultaneously.To accomplish the coordination of the UGVs andUAVs, they are all regarded as individuals of the artificial swarm.Those individuals make control decisions independently of othersbased on the self-organizing strategy. The overall requirements forthe detection swarm are analyzed, and the theoretical model ofthe self-organizing strategy based on a combined individual andenvironmental virtual function is established. The numerical investigationproves that the self-organizing strategy is suitable andscalable to control the detection swarm. To further inspect the engineeringreliability, an experiment set is established in laboratory,and the experimental demonstration shows that the self-organizingstrategy drives the detection swarm forming a close range and multiangularsurveillance configuration of a landing spot.

Research Progress on the Integrated Detection Technology for Forensic Deoxyribonucleic Acid Genetic Markers and Ribonucleic Acid Molecular Markers

Deoxyribonucleic acid(DNA)genetic markers and ribonucleic acid(RNA)molecular markers have been widely used in forensic practices including individual identification,parentage testing,body fluid identification,determination of the age of stains,and molecular pathological diagnosis.Variant information of biological evidence and their interrelation could be revealed by the integrated detection of DNA/RNA markers.The integrated detection workflow aims to simplify working procedures,reduce time consuming and save valuable samples collected from crime scenes.Next-generation sequencing(NGS)may be an effective method for integrated DNA/RNA detection.In this review,DNA/RNA co-extraction strategies,simultaneous detection methods based on capillary electrophoresis were summarized.Research on NGS-based integrated detection methods of DNA and RNA markers was reviewed to provide a reference for forensic medicine researches and applications.

Improved Strategies for CRISPR-Cas12-based Nucleic Acids Detection

The COVID-19 pandemic has brought great challenges to traditional nucleic acid detection technology.Thus,it is urgent to develop a more simple and efficient nucleic acid detection technology.CRISPR-Cas12 has signal amplification ability,high sensitivity and high nucleic acid recognition specificity,so it is considered as a nucleic acid detection tool with broad development prospects and high application value.This review paper discusses recent advances in CRISPR-Cas12-based nucleic acid detection,with an emphasis on the new research methods and means to improve the nucleic acid detection capability of CRISPR-Cas12.Strategies for improving sensitivity,optimization of integrated detection,development of sim-plified detection mode and improvement of quantitative detection capabilities are included.Finally,the future development of CRISPR-Cas12-based nucleic acids detection is prospected.

An Overview of Passive and Active Dust Detection Methods Using Satellite Measurements

In this paper,the methods to detect dust based on passive and active measurements from satellites have been summarized.These include the visible and infrared（VIR） method,thermal infrared（TIR） method,microwave polarized index（MPI） method,active lidar-based method,and combined lidar and infrared measurement（CLIM） method.The VIR method can identify dust during daytime.Using measurements at wavelengths of 8.5,11.0,and 12.0 fan,the TIR method can distinguish dust from other types of aerosols and cloud,and identify the occurrence of dust over bright surfaces and during night.Since neither the VIR nor the TIR method can penetrate ice clouds,they cannot detect dust beneath ice clouds.The MPI method,however,can identify about 85%of the dust beneath ice clouds.Meanwhile,the active lidar-based method,which uses the Cloud-Aerosol Lidar with Orthogonal Polarization（CALIOP） data and five-dimensional probability distribution functions,can provide very high-resolution vertical profiles of dust aerosols.Nonetheless,as the signals from dense dust and thin clouds are similar in the CALIOP measurements,the lidar-based method may fail to distinguish between them,especially over dust source regions.To address this issue,the CLIM method was developed,which takes the advantages of both TIR measurements（to discriminate between ice cloud and dense dust layers） and lidar measurements（to detect thin dust and water cloud layers）.The results obtained by using the new CLIM method show that the ratio of dust misclassification has been significantly reduced.Finally,a concept module for an integrated multi-satellites dust detection system was proposed to overcome some of the weaknesses inherent in the single-sensor dust detection.

Rational design of smart adsorbent equipped with a sensitive indicator via ligand exchange:A hierarchical porous mixed-ligand MOF for simultaneous removal and detection of Hg^(2+)

The increasing accumulation of toxic mercury species in water environment has posed a serious health threat worldwide, making it inevitable to develop the versatile materials to achieve efficient prevention and remediation of mercury pollution. Guided by the solvent-assisted ligand exchange (SALE) approach, this work rationally constructed a mixed-ligand NH2-UiO-66-SH (NSU66) with hierarchical-pore structure by incorporating the thiol-rich ligands (H2DMBD) into the water-stable NH2-UiO-66 (NU66) precursor to act as a smart adsorbent equipped with sensitive detector for simultaneous sensing and removal of Hg2+. Unlike the traditional adsorbents, the as-prepared NSU66 not only exhibits a remarkable removal ability with fast capture rate (within 60.0 min), large uptake capacity (265.29 mg/g), and qualified selectivity, but also possesses satisfactory sensing capability, accompanied by low detection limit (3.50 × 10−2 µM), wide linear range (1.00–99.7 µM), high specificity, and strong anti-interference capability. The detection function plays a vital role in indicating the removal behavior and the pre-enrichment effect of adsorption process correspondingly improves the sensitivity of indicator. Notably, the sensing and trapping capabilities of NSU66 are significantly improved compared to the NU66, which stems from the delicate design of the mixed-ligand and hierarchical-pore structure. Furthermore, proven excellent stability and recyclability emphasize the feasibility of NSU66 in practical applications. These results suggest that the smart NSU66 adsorbent can serve as a favorable platform for early warning and guided removal of toxic Hg2+ in water.

BioLeT: A new design strategy for functional bioluminogenic probes

By integrating photoinduced electron transfer（PET） into the design of functional bioluminogenic probes,Urano and his coworkers recently developed a new rational design strategy, BioLeT. It is expected that this BioLeT strategy will enable us to design and develop new bioluminescence probes for detecting various biomolecules with no catalytic or reactive activity.