Analysis of vehicle rollover using multibody dynamics

This study reports on the analysis of vehicle deformation due to rollover using multi-body dynamics which enables estimating motions of rigid bodies subjected to external forces. For the vehicle rollover analysis using the ADAMS, we have developed a FEA-based numerical vehicle model consisting of a rigid lower body and a deformable upper body. Here, comprehensive analysis of the static and dynamic roof strength resistance of a vehicle using our prediction model is described. We obtain the displacement of A-pillar top-end of a vehicle for each of the static and dynamic tests according to the FMVSS 216 protocol and the Controlled rollover impact system (CRIS) condition, respectively. The displacement of A-pillar top-end represents the roof intrusion causing injuries for passengers in the front seats, thereby evaluating the Strength to weight ratio (SWR) of a vehicle.

     

Induction of PLXNA4 Gene during Neural Differentiation in Human Umbilical-Cord-Derived Mesenchymal Stem Cells by Low-Intensity Sub-Sonic Vibration

Human umbilical-cord-derived mesenchymal stem cells (hUC-MSC) are a type of mesenchymal stem cells and are more primitive than other MSCs. In this study, we identify novel genes and signal-activating proteins involved in the neural differentiation of hUC-MSCs induced by Low-Intensity Sub-Sonic Vibration (LISSV). RNA sequencing was used to find genes involved in the differentiation process by LISSV. The changes in hUC-MSCs caused by LISSV were confirmed by PLXNA4 overexpression and gene knockdown through small interfering RNA experiments. The six genes were increased among genes related to neurons and the nervous system. One of them, the PLXNA4 gene, is known to play a role as a guide for axons in the development of the nervous system. When the PLXNA4 recombinant protein was added, neuron-related genes were increased. In the PLXNA4 gene knockdown experiment, the expression of neuron-related genes was not changed by LISSV exposure. The PLXNA4 gene is activated by sema family ligands. The expression of SEMA3A was increased by LISSV, and its downstream signaling molecule, FYN, was also activated. We suggest that the PLXNA4 gene plays an important role in hUC-MSC neuronal differentiation through exposure to LISSV. The differentiation process depends on SEMA3A-PLXNA4-dependent FYN activation in hUC-MSCs.     

Detection and enumeration of Salmonella enteritidis in homemade ice cream associated with an outbreak: comparison of conventional and real-time PCR methods

Salmonellosis caused by Salmonella Enteritidis (SE) is a significant cause of foodborne illnesses in the United States. Consumption of undercooked eggs and egg-containing products has been the primary risk factor for the disease. The importance of the bacterial enumeration technique has been enormously stressed because of the quantitative risk analysis of SE in shell eggs. Traditional enumeration methods mainly depend on slow and tedious most-probable-number (MPN) methods. Therefore, specific, sensitive, and rapid methods for SE quantitation are needed to collect sufficient data for risk assessment and food safety policy development. We previously developed a real-time quantitative PCR assay for the direct detection and enumeration of SE and, in this study, applied it to naturally contaminated ice cream samples with and without enrichment. The detection limit of the real-time PCR assay was determined with artificially inoculated ice cream. When applied to the direct detection and quantification of SE in ice cream, the real-time PCR assay was as sensitive as the conventional plate count method in frequency of detection. However, populations of SE derived from real-time quantitative PCR were approximately 1 log higher than provided by MPN and CFU values obtained by conventional culture methods. The detection and enumeration of SE in naturally contaminated ice cream can be completed in 3 h by this real-time PCR method, whereas the cultural enrichment method requires 5 to 7 days. A commercial immunoassay for the specific detection of SE was also included in the study. The real-time PCR assay proved to be a valuable tool that may be useful to the food industry in monitoring its processes to improve product quality and safety.     

Effect of substrate on the phase transformation of TiO2 in pearlescent pigment

The TiO₂/substrate pearlescent pigments were prepared by the hydrolysis of TiOCl₂ on the substrate followed by a calcinations process. The natural mica (muscovite), synthetic mica (fluorophlogopite) and -alumina flake were selected as the substrates for pearlescent pigments. The effect of substrate on the anatase to rutile (A–R) phase transformation of TiO₂ was studied. The A–R phase transformation of TiO₂ during the preparation of pearlescent pigments and their proportion in the TiO₂ layer have been analyzed by XRD measurements. The phase compositions of TiO₂ layer in each pearlescent pigment are quite different depending on the substrates. The TiO₂ layer deposited on -alumina has higher rutile fraction than those on the natural and synthetic mica. The XPS analysis showed that the cations originally present in the substrates diffused into the TiO₂ layer. The TiO₂ layer deposited on -alumina contains Al, while those on the natural and synthetic mica substrates contain Si and K in addition to Al. The metal cations diffusing from the substrate into TiO₂ layer might retard the A–R phase transformation of TiO₂. The suppressing effect on the A–R transformation of TiO₂ by mixed cations seems to be much stronger than that of single cation, resulting in relatively higher rutile fraction in the case of TiO₂ layer deposited on -alumina.     

Mechano-electrochemistry of a passive surface using an in situ micro-indentation test

Depassivation–repassivation of iron surfaces in boric–borate solutions were investigated by using the micro-indentation test. A pair of current peaks due to repair of the passive film following rupture of the film were observed during a series of indenter drives, i.e., loading and unloading of the indenter. The shape of the current peak depended on environmental conditions (conductivity and pH of the solution) and substrate conditions (mechanical processing history, alloyed element) as well as indentation conditions (repetition, maximum depth, and maximum load). Plastic deformation of the surface was accompanied by surface depassivation, while no depassivation occurred during the elastic deformation, indicating that the passive film on iron has a ductile property. The solution conditions did not affect the scale of depassivation but affected the rate of repassivation. Dislocations in the substrate made surface depassivation difficult but enhanced reactivity during the repassivation. The test also revealed that type-312L stainless steel has high corrosion resistance in a concentrated NaCl solution.     

Sn self-doped α-Fe2O3 nanobranch arrays supported on a transparent,conductive SnO2 trunk to improve photoelectrochemical water oxidation

We produced hierarchically branched Fe₂O₃ nanorods on a Sb:SnO₂ transparent conducting oxide (TCO) nanobelt structure as photoanodes for photoelectrochemical water splitting. Single-crystalline SnO₂ nanobelts (NBs) surrounded by Fe₂O₃ nanorods (NRs) were synthesized by thermal evaporation, then underwent chemical bath deposition and annealing. When Fe₂O₃ was crystallized by annealing, Sn was diffused from SnO₂ NBs and incorporated to Fe₂O₃ NRs, which was confirmed through Energy dispersive spectroscopy. Unlike previous high temperature sintering (∼800 °C), Sn doped hematite NRs were obtained at a low temperature (∼650 °C). This occurred since SnO₂ NBs directly connected to Fe₂O₃ NRs are an abundant source of Sn dopant. The 3D hematite NRs on SnO₂ NBs annealed at 650 °C produce a photocurrent density of 0.88 mA/cm² at 1.23 V vs. RHE, which is 3 times higher than that of hematite NRs on a fluorine doped tin oxide (FTO) glass substrate annealed at the same temperature. The enhanced photocurrent is attributed to the improved electrical conductivity of Fe₂O₃ NRs by Sn doping, the efficient electron transport pathway by TCO nanowire and the increased surface area by hierarchically branched structure.     

Hybrid approach of parallel implementation on CPU–GPU for high-speed ECDSA verification

The Journal of Supercomputing - Since the advent of deep belief network deep learning technology in 2006, artificial intelligence technology has been utilized in various convergence areas, such as...     

The latent learning model to derive semantic relations of words from unstructured text data in social media

Multimedia Tools and Applications - Unstructured text data is very important in many applications because it reflects the thought of the people who create this data. However, it is difficult to...     

Electrical Properties of Ca<Subscript>9</Subscript>ZnLi(PO<Subscript>4</Subscript>)<Subscript>7</Subscript> Ceramics Prepared by Reactive Pressureless Sintering

Well-crystallized Ca₉ZnLi(PO₄)₇ ceramics were prepared by reactive pressureless sintering at atmospheric pressure. The single-phase Ca₉ZnLi(PO₄)₇ ceramics were confirmed by x-ray diffraction (XRD). The dielectric and electrical properties were investigated over a wide frequency range (1 Hz to 1 MHz) by complex impedance spectroscopy at different temperatures between 25°C and 600°C. A dielectric anomaly was observed at 440°C, which might be related to the phase transition. The impedance Cole–Cole plot was used to analyze the results of complex impedance measurements, revealing that the electrical properties depend strongly on frequency and temperature. Two relaxation dispersions of the electrical parameters were found and analyzed in terms of bulk and grain-boundary ionic transfer processes. The slope of the alternating-current (AC) conductivity over a wide range of temperatures provides activation energies from 0.48 eV to 1.69 eV. These results suggest that the conduction process is of the mixed type.