Context-Aware Data Augmentation for LIDAR 3D Object Detection

For 3D object detection, labeling lidar point cloud is difficult, so data augmentation is an important module to make full use of precious annotated data. As a widely used data augmentation method, GT-sample effectively improves detection performance by inserting groundtruths into the lidar frame during training. However, these samples are often placed in unreasonable areas, which misleads model to learn the wrong context information between targets and backgrounds. To address this problem, in this paper, we propose a context-aware data augmentation method (CA-aug) , which ensures the reasonable placement of inserted objects by calculating the "Validspace" of the lidar point cloud. CA-aug is lightweight and compatible with other augmentation methods. Compared with the GT-sample and the similar method in Lidar-aug(SOTA), it brings higher accuracy to the existing detectors. We also present an in-depth study of augmentation methods for the range-view-based(RV-based) models and find that CA-aug can fully exploit the potential of RV-based networks. The experiment on KITTI val split shows that CA-aug can improve the mAP of the test model by 8%.Comment: 6 pages, 4 figure

The effect of intermittent versus continuous enteral feeding for critically ill patients: a meta-analysis of randomized controlled trials

ObjectivesThe appropriate strategy for enteral feeding in critically ill patients still remains controversial. Therefore, we conducted this meta-analysis to compare the effect of intermittent versus continuous enteral feeding method for critically ill patients.MethodsElectronic databases including PubMed, Embase, Scopus, and Cochrane Library were searched up to April 10th, 2023 for randomized controlled trials evaluating the effect of intermittent versus continuous enteral feeding for critically ill patients. The primary outcomes were feeding intolerances, including diarrhea, vomiting, distension, constipation, gastric retention, and aspiration pneumonia. The secondary outcomes were mortality in intensive care unit (ICU), length of stay in ICU, and achievement of nutritional goal.ResultsThirteen studies with a total of 884 patients were analyzed in this meta-analysis. Overall, the use of intermittent enteral feeding was associated with higher incidence of diarrhea (OR 1.66, 95%CI 1.13 to 2.43, I2 = 16%) and distension (OR 2.29, 95%CI 1.16 to 4.51, I2 = 0%), lower incidence of constipation (OR 0.58, 95%CI 0.37 to 0.90, I2 = 0%), and longer length of ICU stay (MD 1.09, 95%CI 0.53 to 1.64, I2 = 0%). Moreover, no significant difference was identified for other outcome measures.ConclusionIn critically ill patients, the implementation of intermittent enteral feeding was associated with higher incidence of diarrhea and distension, longer length of ICU stay, but lower occurrence of constipation. Nevertheless, the absence of sufficient high-quality randomized controlled clinical trials precludes any definitive conclusions regarding the optimal approach to enteral feeding in this population. There is an imperative need for more studies to further assess the efficacy of the two enteral feeding strategies

Impurities Removal from Metallurgical-Grade Silicon by Combined Sn-Si and Al-Si Refining Processes

The purification of metallurgical-grade silicon (MG-Si) by combined solvent refining processes has been studied. The final high-purity silicon was recovered through Sn-Si refining and Al-Si refining processes in sequence after acid leaching, and the removal mechanism of impurities was explored. Inductively coupled plasma (ICP) chemical analysis revealed the concentrations of main impurities including B and P, and typical metallic impurities except for solvents Sn and Al were reduced to below 1 ppmw. The final removal efficiencies of B and P were 97.7 pct and 99.8 pct, respectively, and those of most metallic impurities were above 99.9 pct. SEM analysis showed that P-containing phases (Al-Ca-Mg-Si-P and Al-Si-P) formed on the surface of refined Si after Sn-Si refining and Al-Si refining, which was confirmed to be the main approach for P removal. It was also found that the formation of binary silicide such as Fe3Si7 and Mn11Si19 or multicomponent phases such as Ca-Mg-Si phase occurred during the solvent refining process, and they segregated on the grain boundaries in Si or attached to the surface of Si, which led to high removal efficiency of metallic impurities by the solvent refining process

Purification of metallurgical-grade silicon by Sn-Si refining system with calcium addition

Purification of metallurgical-grade silicon (MG-Si) by a combination of solvent refining and super gravity separation and acid leaching has been studied. MG-Si was alloyed with tin, and based on this system, the removal of main impurities in MG-Si by solvent refining was investigated. Furthermore, phosphorus removal by calcium addition in molten Si and Sn-Si melt was also studied. Inductively Coupled Plasma (ICP) chemical analysis revealed main impurities including B and P could be efficiently removed by the Sn-Si process and acid leaching. The content of P further reduced when Ca was added to the Sn-Si refining system. Scanning Electron Microscopy-Energy Dispersive Spectroscopy (SEM-EDS) analysis showed that the formation of compounds between P and several elements in the grain boundaries during the solvent refining process was an important routine of P removal. The maximum weight percent of P in P-containing impurity phases reached to 17.8% in the refined Si after the Sn-Si refining process with Ca addition. (C) 2013 Elsevier B.V. All rights reserved

Intensified hydrogen production and desulfurization at elevated temperature and pressure during coal electrolysis

Elevation of temperature and pressure was used as an effective way to reduce the electrochemical resistance and improve the liquid mass transfer during the coal electrolysis without membrane, thus enhancing the desulfurization and hydrogen production. Results indicated that the high temperature and pressure have effectively reduced the electrochemical resistance (R-ct) and solution resistance (R-s) for coal electrolysis. The oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) potentials for coal-water slurry electrolysis was obviously seen to increase with increasing temperature and pressure. What&#39;s more, the difference between the potential of OER and the equilibrium potential of OER (overpotential) also increased with the intensified condition, which was defined as the metastable zone width (MZW), indicating that HO center dot formation was improved by the high temperature and pressure. As expected, the elevation in temperature and pressure has successfully resulted in the decrease in cell voltage and the increase in coal desulfurization during the electrolysis. (C) 2018 Elsevier Ltd. All rights reserved.</p

Behavioral evidence for cone-based ultraviolet vision in divergent bat species and implications for its evolution

We investigated the reactions of four bat species from four different lineages to UV light: Hipposideros armiger (Hodgson, 1835) and Scotophilus kuhlii Leach, 1821, which use constant frequency (CF) or frequency modulation (FM) echolocation, respectively; and Rousettus leschenaultii (Desmarest, 1820) and Cynopterus sphinx (Vahl, 1797), cave and tree-roosting Old World fruit bats, respectively. Following acclimation and training involving aversive stimuli when exposed to UV light, individuals of S. kuhlii and C. sphinx exposed to such stimuli displayed conditioned reflexes such as body crouching, wing retracting, horizontal crawling, flying and/or vocalization, whereas individuals of H. armiger and R. leschenaultii, in most cue-testing sessions, remained still on receiving the stimuli. Our behavioral study provides direct evidence for the diversity of cone-based UV vision in the order Chiroptera and further supports our earlier postulate that, due to possible sensory tradeoffs and roosting ecology, defects in the short wavelength opsin genes have resulted in loss of UV vision in CF bats, but not in FM bats. In addition, Old World fruit bats roosting in caves have lost UV vision, but those roosting in trees have not. Bats are thus the third mammalian taxon to retain ancestral cone-based UV sensitivity in some species

Roles of Ultrasound on Hydroxyl Radical Generation and Bauxite Desulfurization from Water Electrolysis

Roles of ultrasound on the hydroxyl radical generation from water electrolysis were examined in this work. Results indicated that the ultrasound could not only strengthen the mass transfer of liquid phase, but also could improve the electron gain and loss for hydroxyl ion, and thus improve the hydroxyl radical generation. Results from ESR signal indicated that, ultrasonic strengthened hydroxyl radical formation from water electrolysis in whatever in alkaline or acidic solution. Ultrasound improved the equilibrium potential and current of OER, indicating that ultrasound inhibited the thermodynamics conditions in OER. Ultrasound inhibited the oxygen gas release, and thus resulting in the increase in the amount of hydroxyl radicals. The R-ct of OER increased with ultrasound addition, while the R-s for water electrolysis decreased. Whatever platinum (Pt) or nickel (Ni) electrode, bauxite electrolysis desulfurization all were improved by ultrasound, and the desulfurization of Ni under ultrasound was higher than Pt without ultrasound. That is, electrolysis desulfurization with Ni electrode in presence of ultrasound could replace electrolysis desulfurization with Pt electrode in absence of ultrasound. (C) 2018 The Electrochemical Society.</p

Pressure intensified HO center dot evolution from OER and electrolysis desulfurization

To strengthen the formation of Hydroxyl radical (HO center dot) on anode, pressurized water electrolysis under constant temperature were carried out in this work. The HO center dot formation was verified by electrochemistry-electron spin resonance (ESR) and bauxite desulfurization in the same pressurized reactor with different cell designs. With increasing pressure, the current density was increased. However, the equilibrium potential of anode and the initial potential of oxygen evolution reaction (OER) were negative shifted with increasing pressure. Results revealed that pressure promoted the early steps of OER but inhibited subsequent transformation. The apparent transfer coefficient of the anode (b(a) and b(c)) further proved that the pressure play a positive role on the OER reserve reaction and promoted the formation of HO center dot. R-ct and R-s were all decreased with increasing pressure, demonstrating that pressure improved the mass transfer and reaction of the OER. The electrolysis desulfurization and ESR experiments have clearly supported the positive role of pressure on strengthening the HO center dot formation. From electrolysis with 0.1 MPa, HO center dot signal was detected by ESR when constant potential was 0.8 V on anode, while the signal arose at 0.7 V under 1.0MPa, indicating that HO center dot was formed in advance under pressure. (C) 2019 Elsevier Ltd. All rights reserved

electrochemicalbehaviorsofanodematerialsandtheirperformanceforbauxitedesulfurization

Pyrite inside bauxite could be oxidized into soluble S-containing ions by electrolysis, and thus achieving bauxite desulfurization by using filtration. However, S-containing ions in electrolyte had some corrosion effects on electrode, especially for anode. In this work, six kinds of traditional materials were selected as anode, and their corrosion behaviors were examined by using electrochemistry characterization. Tafel and CV curves from simulating electrolyte suggested that their corrosion potentials were in the following order: Ni > C > SS > Fe > Cu > Pb-Ag. As expected, the desulfurization ratio and cell voltage from bauxite electrolysis were in the following order respectively: Cu > Ni > Fe > SS > C > Pb-Ag and Ni > Fe > SS > Cu > C > Pb-Ag. Finally, Ni was proposed a kind of excellent electrode material for bauxite desultitrization from electrolysis. (C) 2018 The Chemical Industry and Engineering Society of China, and Chemical Industry Press Co., Ltd All rights reserved