373 research outputs found
Investigation of Electrical Component Failures Affecting Vehicle Electronics
This dissertation describes three independent studies related to electrical component failures affecting vehicle electronics. The topics covered are: comparison of the accelerator-pedal-to-engine-control module (AP-to-ECM), the effect of electrical fast transients on multi-layer ceramic (MLC) capacitors, and electrical behavior of MLC capacitors damaged by electrostatic discharge.
The first chapter examines the AP-to-ECM interfaces of five vehicles equipped with electronic throttle control systems. All five vehicles employ simple voltage level sensing from two or three sensors in the accelerator pedal assembly. The purpose of the study is to identify any differences in the AP-to-ECM interfaces of vehicles with high reported rates of unintended acceleration compared to vehicles with low reported rates of unintended acceleration. The study does not attempt to identify the root causes of unintended acceleration; however it points out important design issues that suggest a set of best practices for electronic throttle control design.
The second chapter investigates the susceptibility of MLC capacitors to high-voltage electrical fast transients (EFTs). X7R and NP0 MLC capacitors with a 50-V voltage rating and 0603 package size were tested. X7R capacitors often failed during a spike in the voltage, but exhibited no obvious degradation in the measured insulation resistance at low voltages immediately after the failure. NP0 capacitors usually failed by suddenly shorting and maintaining the short after the failure. With the application of additional voltage spikes, some X7R capacitors exhibited a full recovery in terms of the measured resistance, returning to their initial state. The resistance of an X7R capacitor damaged by an EFT event is a function of the applied voltage. The terminal impedance can be modeled as two diodes in parallel.
The third chapter investigates the electrical behavior of MLC capacitors subjected to electrostatic discharge (ESD). The degradation of MLC capacitors subjected to repeated discharges manifests itself as a non-linear resistance. The leakage current in degraded capacitors increases exponentially with an applied voltage. The I-V characteristics of these capacitors are symmetric with voltage and independent of the polarity of the ESD discharges responsible for the degradation. A model for a degraded capacitor consisting of two parallel diodes with opposite polarities is proposed
Data Calibration Based on Multisensor Using Classification Analysis: A Random Forests Approach
This paper analyzes the problem of meaningless outliers in traffic detective data sets and researches characteristics about the data of monophyletic detector and multisensor detector based on real-time data on highway. Based on analysis of the current random forests algorithm, which is a learning algorithm of high accuracy and fast speed, new optimum random forests about filtrating outlier in the sample are proposed, which employ bagging strategy combined with boosting strategy. Random forests of different number of trees are applied to analyze status classification of meaningless outliers in traffic detective data sets, respectively, based on traffic flow, spot mean speed, and roadway occupancy rate of traffic parameters. The results show that optimum model of random forest is more accurate to filtrate meaningless outliers in traffic detective data collected from road intersections. With filtrated data for processing, transportation information system can decrease the influence of error data to improve highway traffic information services
Personal Identification Based on Live Iris Image Analysis
EThOS - Electronic Theses Online ServiceGBUnited Kingdo
Identification of natural killer cell associated subtyping and gene signature to predict prognosis and drug sensitivity of lung adenocarcinoma
Introduction: This research explored the immune characteristics of natural killer (NK) cells in lung adenocarcinoma (LUAD) and their predictive role on patient survival and immunotherapy response.Material and methods: Molecular subtyping of LUAD samples was performed by evaluating NK cell-associated pathways and genes in The Cancer Genome Atlas (TCGA) dataset using consistent clustering. 12 programmed cell death (PCD) patterns were acquired from previous study. Riskscore prognostic models were constructed using Least absolute shrinkage and selection operator (Lasso) and Cox regression. The model stability was validated in Gene Expression Omnibus database (GEO).Results: We classified LUAD into three different molecular subgroups based on NK cell-related genes, with the worst prognosis in C1 patients and the optimal in C3. Homologous Recombination Defects, purity and ploidy, TMB, LOH, Aneuploidy Score, were the most high-expressed in C1 and the least expressed in C3. ImmuneScore was the highest in C3 type, suggesting greater immune infiltration in C3 subtype. C1 subtypes had higher TIDE scores, indicating that C1 subtypes may benefit less from immunotherapy. Generally, C3 subtype presented highest PCD patterns scores. With four genes, ANLN, FAM83A, RHOV and PARP15, we constructed a LUAD risk prediction model with significant differences in immune cell composition, cell cycle related pathways between the two risk groups. Samples in C1 and high group were more sensitive to chemotherapy drug. The score of PCD were differences in high- and low-groups. Finally, we combined Riskscore and clinical features to improve the performance of the prediction model, and the calibration curve and decision curve verified that the great robustness of the model.Conclusion: We identified three stable molecular subtypes of LUAD and constructed a prognostic model based on NK cell-related genes, maybe have a greater potential for application in predicting immunotherapy response and patient prognosis
A comparison of perceptual anticipation in combat sports between experts and non-experts: A systematic review and meta-analysis
In order to systematically evaluate perceptual anticipation between experts and non-experts for different kinds of combat sports, we needed to perform a comprehensive assessment. In this systematic review and meta-analysis, we searched four English-language and three Chinese-language databases that used expert/non-expert research paradigms, to explore perceptual anticipation in combat sports. We employed a random effects model for pooled analyses using the inverse variance method. We included 27 eligible studies involving 233 datasets in this meta-analysis. We observed large effect sizes for the differences between experts and non-experts in both response accuracy (1.51; 95% CI: 1.15 to 1.87, p < 0.05) and reaction time (-0.91; 95% CI: −1.08 to−0.73, p < 0.05). We also observed substantial differences between experts and non-experts in the mean duration of visual fixations per trial (1.51; 95% CI: −2.40 to −0.63, p < 0.05), but not in the visual fixation duration (0.16; −061 to 0.92, p = 0.69). Taken together, high-level combat athletes have more advantages in perceptual anticipation than lower-level athletes, showing faster and more accurate responses when facing the opponent's attacks, as well as focusing on fewer points of visual fixations than novice athletes. Different types of combat sports and stimulus presentations affect perceptual anticipation abilities to varying extents in relation to outcome measures, with more pronounced expertise in a stimulus that is closer to real-world situations
Tracking hantavirus nucleocapsid protein using intracellular antibodies
<p>Abstract</p> <p>Background</p> <p>Hantavirus nucleocapsid (N) protein is a multifunctional viral macromolecule involved in multiple stages of the viral replication cycle. The intracellular trafficking of N protein during virus assembly remains unclear.</p> <p>Methods</p> <p>We used N protein-specific intracellular expressed antibodies to track the localization and distribution of Hantaan virus and Seoul virus N protein. The N protein-specific antibody single-chain variable antibody fragments (scFvs), which bind an N-terminal linear epitope (L13F3) and C-terminal conformational domain (H34), were intracellularly expressed in the endoplasmic reticulum (ER) by fusion of the SEKDEL retention signal peptide at the carboxyl terminus, and in the cytoplasm (Cyto) by deletion of the ER membrane target signal peptide. Stable Vero-E6 cell lines expressing intracellular scFvs were either infected with hantavirus or transfected with an N protein expression plasmid; virus replication and N protein intracellular localization were determined.</p> <p>Result</p> <p>N protein co-localized with scFvs in the ER and cytoplasm with or without viral membrane glycoproteins. Hantavirus replication was inhibited in both the scFvs-ER- and scFvs-Cyto-expressing stable cell lines.</p> <p>Conclusion</p> <p>N protein may be expressed in the ER retention signal peptide of KDEL circulating region (ER/<it>cis</it>-Golgi) without the assistance of G protein, and so expression of N protein in both the cytoplasm and within the ER/<it>cis</it>-Golgi plays an important role in virus replication.</p
Self-Efficacy and Depression in Boxers: A Mediation Model
Background: Depression has become one of the most common problems faced by athletes. In many mental health problems, its production and development mechanisms and influencing factors have received full attention from researchers, whereas boxers’ depression has received limited attention. This study explored the relationship between boxers’ self-efficacy and depression, as well as the effect of self-control as a mediating factor.
Methods: This study used the athlete self-efficacy scale (ASES), the self-control scale (SCS), and the Center for Epidemiologic Studies depression scale (CES-D). Using a large number of randomly selected samples, a total of N=231 boxers (age: M =20.28, SD = 2.60, ages around 18 to 32; the total number of years of exercise: M = 6.07 years, SD = 2.90, years around 1 to 15; 144 male) of Chinese national athletes participated the study.
Results: Self-efficacy and self-control were negatively correlated with depression; self-efficacy was positively correlated with self-control. In addition, self-control played a partial mediation role between self-efficacy and depression among boxers.
Conclusion: Above all, an important way to improve and prevent the depression of Chinese boxers maybe enhance their level of self-efficacy and self-control
4D Human Body Capture from Egocentric Video via 3D Scene Grounding
We introduce a novel task of reconstructing a time series of second-person 3D
human body meshes from monocular egocentric videos. The unique viewpoint and
rapid embodied camera motion of egocentric videos raise additional technical
barriers for human body capture. To address those challenges, we propose a
simple yet effective optimization-based approach that leverages 2D observations
of the entire video sequence and human-scene interaction constraint to estimate
second-person human poses, shapes, and global motion that are grounded on the
3D environment captured from the egocentric view. We conduct detailed ablation
studies to validate our design choice. Moreover, we compare our method with the
previous state-of-the-art method on human motion capture from monocular video,
and show that our method estimates more accurate human-body poses and shapes
under the challenging egocentric setting. In addition, we demonstrate that our
approach produces more realistic human-scene interaction
Fusion with extracellular domain of cytotoxic T-lymphocyte-associated-antigen 4 leads to enhancement of immunogenicity of Hantaan virus DNA vaccines in C57BL/6 mice
<p>Abstract</p> <p>Background</p> <p>Hantaan virus (HTNV) is the causative agent of the most severe form of a rodent-borne disease known as hemorrhagic fever with renal syndrome (HFRS). A safe and effective HTNV vaccine is needed. Vaccination with DNA constructs expressing fused antigen with bioactive factors, has shown promising improvement of immunogenicity for viral agents in animal models, but the effect of fusion strategy on HTNV DNA vaccine has not been investigated.</p> <p>Results</p> <p>DNA plasmids encoding the HTNV nucleocapsid protein (N) and glycoprotein (Gn and Gc) in fusion to the extracellular domain of cytotoxic T-lymphocyte-associated-antigen 4 (eCTLA-4) targeting to antigen presenting cells (APCs) were constructed. Intramuscular immunization of mice with plasmids expressing eCTLA-4-HTNV-N/GP fusion proteins leads to a significant enhancement of the specific antibody response as well as cytotoxic T-lymphocyte (CTL) response in C57BL/6 mice. Moreover, this effect could be further augmented when co-administered with CpG motifs.</p> <p>Conclusions</p> <p>Modification of viral antigen in fusion to bioactive factor will be promising to confer efficient antigen presentation and improve the potency of DNA vaccine in mice.</p
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