Demonstration of PI2: Interactive Visualization Interface Generation for SQL Analysis in Notebook

We demonstrate PI2, the first notebook extension that can automatically generate interactive visualization interfaces during SQL-based analyses.Comment: arXiv admin note: text overlap with arXiv:2107.0820

Dead-time compensation and single-loop control strategy for ground power unit

Instead of the auxiliary power system, the ground power unit supplies to airplanes during stopovers in airports, which is an important means of reducing carbon emissions of airport. However, under the restraint of switching frequency and high dynamic response speed, a single control loop is usually implemented in 400 Hz voltage-source inverter, the sampling and control of the inductor current in the LC filter are avoided, result in the design of the control system being more difficult, and the direction of the dead-time compensation can not be obtained due to the lack of the current polarity. In view of the above problem, this paper firstly analyzes the influence on the output voltage of inverter due to the dead-time, including the errors of fundamental amplitude and phase, and the low-order harmonic distortion. Then, according to the state equation of the inductor current, a current observation model without zero drift is proposed to obtain the polarity of the inductor current. On this basis, feedforward compensation is carried out for the voltage error generated by the dead-time. Combined with the amplitude-frequency characteristic curve, the parameter optimization design method of the single closed-loop proportional-resonant controller is presented. Finally, a simulation model and an experimental platform are established to verify the feasibility and effectiveness of the current observation model, dead-time compensation method and controller parameter optimization design method proposed in this paper

A novel weighting factor determined method of model predictive torque control for permanent magnet synchronous motor

In the cost function of model predictive torque control (MPTC) of permanent magnet synchronous motor (PMSM), torque and flux linkage have different dimensions, and the weighting factor needs to be properly adjusted to optimise the control performance. Therefore, based on the discrete mathematical model of PMSM, the torque predictive error and flux predictive error expressions are mapped to the two-phase static coordinate system, which is equivalent to the distance expressions from the endpoint of the voltage vector to the straight line and to the circle respectively. Because they have the same dimension, they can be directly superimposed to form the cost function proposed, which eliminates the selection process of the weighting factor. Then, the candidate voltage vector is substituted into the cost function in turn, and the optimal voltage vector with the minimum cost function is selected as the voltage input of the next control cycle. Finally, the simulation model and an experimental platform are established to compare the steady-state and dynamic performance of the geometric solution-based weighting factor determined method proposed with other MPTC methods

SARS-CoV-2 Vaccine-Related Liver Failure: Active Hepatitis B and Comprehensive Literature Analysis

SARS-CoV-2 infection or vaccination is closely associated with liver injury, and autoimmune hepatitis episodes have been described, but liver failure has not been reported. Here, we report the case of a 41-year-old man, presenting with fatigue, anorexia after activity, greasy, decreased intake, yellow urine, and occasionally acid reflux in the stomach, occurring 2–3 weeks after receiving the first dose of inactivated SARS-CoV-2 vaccination, thought to be associated with his underlying chronic hepatitis B and fatty liver condition. The patient took the drug irregularly and did not achieve viral conversion to negative and appear rtA181T-resistant HBV mutation. Recently, the laboratory results showed abnormal liver function with high alanine aminotransferase (ALT), aspartate aminotransferase (AST), and γ-glutamyl transferase (GGT), and there was no improvement in liver function after hepatoprotective therapy, and the serum hepatitis B virus (HBV) concentration was greater than 2.0 × 106 IU/mL. Later, after being admitted to our hospital, it was found that he was in, malaise, jaundice, his eyes and sclera were yellow, his lungs were coarse breath sounds, his liver function was abnormally elevated, and his HBV virus developed a drug-resistant mutation. He has no history of autoimmune disease and tests negative for autoimmune antibodies. He became severely ill after intermittently stopping HBV treatment, worsened liver injury after inactivated SARS-CoV-2 vaccination, and was diagnosed with acute-on-chronic liver failure (ACLF). By summarizing the case report, it will provide important information on the vaccine safety assessment of vaccine components, immunization routes, and dosage for people with underlying liver disease

Genetic insights into the dissolution of dioecy in diploid persimmon Diospyros oleifera Cheng

BACKGROUND: Dioecy, a sexual system of single-sexual (gynoecious/androecious) individuals, is rare in flowering plants. This rarity may be a result of the frequent transition from dioecy into systems with co-sexual individuals. RESULTS: In this study, co-sexual expression (monoecy and hermaphroditic development), previously thought to be polyploid-specific in Diospyros species, was identified in the diploid D. oleifeara historically. We characterized potential genetic mechanisms that underlie the dissolution of dioecy to monoecy and andro(gyno)monoecy, based on multiscale genome-wide investigations of 150 accessions of Diospyros oleifera. We found all co-sexual plants, including monoecious and andro(gyno)monoecious individuals, possessed the male determinant gene OGI, implying the presence of genetic factors controlling gynoecia development in genetically male D. oleifera. Importantly, discrepancies in the OGI/MeGI module were found in diploid monoecious D. oleifera compared with polyploid monoecious D. kaki, including no Kali insertion on the promoter of OGI, no different abundance of smRNAs targeting MeGI (a counterpart of OGI), and no different expression of MeGI between female and male floral buds. On the contrary, in both single- and co-sexual plants, female function was expressed in the presence of a genome-wide decrease in methylation levels, along with sexually distinct regulatory networks of smRNAs and their targets. Furthermore, a genome-wide association study (GWAS) identified a genomic region and a DUF247 gene cluster strongly associated with the monoecious phenotype and several regions that may contribute to andromonoecy. CONCLUSIONS: Collectively, our findings demonstrate stable breakdown of the dioecious system in D. oleifera, presumably also a result of genomic features of the Y-linked region

Effects of tumor necrosis factor-α polymorphism on the brain structural changes of the patients with major depressive disorder

Single Nucleotide Polymorphic (SNP) variations of proinflammatory cytokines such as Tumor Necrosis Factor-α (TNF-α) have been reported to be closely associated with the major depressive disorder (MDD). However, it is unclear if proinflammatory genetic burden adversely affects the regional gray matter volume in patients with MDD. The aim of this study was to test whether rs1799724, an SNP of TNF-α, contributes to the neuroanatomical changes in MDD. In this cross-sectional study, a total of 144 MDD patients and 111 healthy controls (HC) well matched for age, sex and education were recruited from Shanghai Mental Health Center. Voxel-based morphometry (VBM) followed by graph theory based structural covariance analysis was applied to locate diagnosis x genotype interactions. Irrespective of diagnosis, individuals with the high-risk genotype (T-carriers) had reduced volume in left angular gyrus (main effect of genotype). Diagnosis x genotype interaction was exclusively localized to the visual cortex (right superior occipital gyrus). The same region also showed reduced volume in patients with MDD than HC (main effect of diagnosis), with this effect being most pronounced in patients carrying the high-risk genotype. However, neither global nor regional network of structural covariance was found to have group difference. In conclusion, a genetic variation which can increase TNF-α expression selectively affects the anatomy of the visual cortex among the depressed subjects, with no effect on the topographical organization of multiple cortical regions. This supports the notion that anatomical changes in depression are in part influenced by the genetic determinants of inflammatory activity

Flexible and integrated sensing platform of acoustic waves and metamaterials based on polyimide coated woven carbon fibers

Versatile, in situ sensing and continuous monitoring capabilities are critically needed but challenging for components made of solid woven carbon fibers in aerospace, electronics and medical applications. In this work, we proposed a unique concept of integrated sensing technology on woven carbon fibers through integration of thin film surface acoustic wave (SAW) technology and electromagnetic metamaterials, with capabilities of non-invasive, in-situ and continuous monitoring of environmental parameters and biomolecules wirelessly. Firstly, we fabricated composite materials using a three-layer composite design, in which the woven carbon fiber cloth was firstly coated with a polyimide (PI) layer followed by a layer of ZnO film. Integrated SAW and metamaterials devices were then fabricated on this composite structure. Temperature of the functional area of the device can be controlled precisely using the SAW devices, which can provide a proper incubation environment for biosampling processes. As a demonstration for an ultraviolet light sensor, the SAW device could achieve a good sensitivity of 56.86 ppm/(mW∙cm-2). On the same integrated platform, the electromagnetic resonator based on the meta-materials has been demonstrated to work as a glucose concentration monitor with a sensitivity of 0.34 MHz/(mg/dL)

Research on the Modulation and Control Strategy for a Novel Single-Phase Current Source Inverter

Compared to the voltage source inverter, the current source inverter (CSI) can boost voltage and improve filtering performance. However, the DC side of CSI is not a real current source, and the DC input current comprises a DC power supply and an inductor. In the switching process, the DC-link inductor is charged or discharged and is in an uncontrollable state. This paper proposes a novel CSI topology containing five switching tubes and a modulation strategy based on the hysteresis control strategy of the DC-link current. Due to the conduction and switching loss being positive to the DC-link current, the calculation method for the least reference value of the DC-link current is derived to meet power requirements. By constructing a virtual axis, we then present the control strategy of the output voltage in a two-phase rotating reference frame. Finally, we carry out the simulation and experiment are to validate the proposed topology, modulation, and control strategy

Design of multi-person cooperative emergency exercise system in coal mine

Traditional coal mine emergency exercise was restricted by environment with high cost and hidden danger, and existing coal mine emergency exercise system failed to consider multi-person coordination. In view of above problems, combining with application requirements of multi-person coordination in coal mine emergency exercise, a multi-person cooperative emergency exercise system in coal mine was designed, which included presentation layer, service layer and storage layer. By simulating and reproducing real mine environment and disaster scenario, multi-department and multi-person are organized to conduct collaborative exercise in the same space and time dimension. The pilot application results show that the system can meet nearly one hundred persons simultaneously conduct online collaborative emergency exercise, which effectively improves ability of participants to deal with disaster and cooperate with each other