1,405 research outputs found

    Traffic Light Recognition for Real Scenes Based on Image Processing and Deep Learning

    Get PDF
    Traffic light recognition in urban environments is crucial for vehicle control. Many studies have been devoted to recognizing traffic lights. However, existing recognition methods still face many challenges in terms of accuracy, runtime and size. This paper presents a novel robust traffic light recognition approach that takes into account these three aspects based on image processing and deep learning. The proposed approach adopts a two-stage architecture, first performing detection and then classification. In the detection, the perspective relationship and the fractal dimension are both considered to dramatically reduce the number of invalid candidate boxes, i.e. region proposals. In the classification, the candidate boxes are classified by SqueezeNet. Finally, the recognized traffic light boxes are reshaped by postprocessing. Compared with several reference models, this approach is significantly competitive in terms of accuracy and runtime. We show that our approach is lightweight, easy to implement, and applicable to smart terminals, mobile devices or embedded devices in practice

    Generational Differences in Household Car Ownership

    Get PDF
    The stagnation of car demand had been observed in many countries. A similar phenomenon had emerged in Taiwan. From the perspective of socio-demographic characteristics, this study employs quantile regression for count data to investigate generational differences in household car ownership in Taiwan. The results show that the socio-demographic characteristics affected household car ownership. Due to the seniority effects, households in the later life-cycle stages and households with a higher proportion of elderly members would reduce car demand. But, households with the middle-aged heads owned more cars due to their better economic ability. The income effects are greater for higher income households. Household car ownership varied across generations, which was related to the income effects, the life course, and household structure. Hence, the demographic changes and generational differences in travel preferences should be considered in urban transportation planning. Seamless transportation and senior-friendly facilities would be important for transportation demand management

    The Relationships among Buyers’ Perceived Risk, Exhibitors’ Brand Equity, Purchase Postponement and Switching Intention-From the Perspectives of Perceived Risk Theory and Expectancy Theory

    Get PDF
    This study explores the effects of buyers’ perceived risk on their purchase postponement and switching intention in an international industrial fair, as well as examines the moderating effect of exhibitors’ brand equity on the above relationships. This study uses the purposive sampling method to survey buyers of the famous International Woodworking Machine Fair in Hanover, Germany. Of the 200 surveys distributed, 105 valid questionnaires were returned, representing a response rate of 52.50%. Analytical results show that higher buyers’ perceived risk is associated with buyers’ higher purchase postponement, and stronger switching intention. Furthermore, when facing high-brand equity exhibitors’ products, if buyers perceive low risk of use, they are unlikely to delay purchase and switch suppliers; in contrast, if they perceive high risk of use, they are more likely to delay purchase and switch suppliers. Finally, when buyers face low-brand equity exhibitors’ products, if they perceive low risk of use, they will delay purchase and switch suppliers; in contrast, if they perceive high risk of use, they will tend not to delay purchase and switch suppliers

    Motivations between First-time and Repeat Business Visitors: A Confirmatory Factor Analysis Approach

    Get PDF
    Understanding tourism motivations is now seen as a veryuseful tool for tourism marketers to increase their patronage and profits.The purpose of this study is to identify systematic differences ofparticular determinant motivations for business trips across two types ofvisitors. The study used quantitative methodology. The paper employedthe following statistic techniques: the exploratory factor analysis,confirmatory factor analysis, t-test analysis to identify two differentsegments among business visitors. The study found that business visitorsfor a single work related trip were more likely to travel with motives,including the motives of seeking educational values, exploration of thenovel, career enhancement, and opportunity for travel. It is thereforecrucial that tourist managers recognize that repeat visitors were morelikely to traveling with recreational associated reasons than these firsttimers, such as: see new things , experience different culture andsightseeing. Theoretical and marketing implications were discussed

    Electron energy-loss spectroscopy and ab initio electronic structure of the LaOFeP superconductor

    Full text link
    The electronic band structures of the LaOFeP superconductor have been calculated theoretically by the first principles method and measured experimentally by electron energy loss spectroscopy. The calculations indicate that the Fe atom in LaOFeP crystal shows a weak magnetic moment and does not form a long-range magnetic ordering. Band structure, Fermi surfaces and fluorine-doping effects are also analyzed based on the data of the density functional theory. The fine structures of the EELS data have been carefully examined in both the low loss energy region and the core losses region (O K, Fe L2,3, and La M4,5). A slight bump edge at 44 eV shows notable orientation-dependence: it can be observed in the low loss EELS spectra with q parallel to c, but becomes almost invisible in the q vertical to c spectra. Annealing experiments indicate that low oxygen pressure favors the appearance of superconductivity in LaOFeP, this fact is also confirmed by the changes of Fe L2,3 and O K excitation edges in the experimental EELS data

    A Kinase Chaperones Hepatitis B Virus Capsid Assembly and Captures Capsid Dynamics in vitro

    Get PDF
    The C-terminal domain (CTD) of Hepatitis B virus (HBV) core protein is involved in regulating multiple stages of the HBV lifecycle. CTD phosphorylation correlates with pregenomic-RNA encapsidation during capsid assembly, reverse transcription, and viral transport, although the mechanisms remain unknown. In vitro, purified HBV core protein (Cp183) binds any RNA and assembles aggressively, independent of phosphorylation, to form empty and RNA-filled capsids. We hypothesize that there must be a chaperone that binds the CTD to prevent self-assembly and nonspecific RNA packaging. Here, we show that HBV capsid assembly is stalled by the Serine Arginine protein kinase (SRPK) binding to the CTD, and reactivated by subsequent phosphorylation. Using the SRPK to probe capsids, solution and structural studies showed that SRPK bound to capsid, though the CTD is sequestered on the capsid interior. This result indicates transient CTD externalization and suggests that capsid dynamics could be crucial for directing HBV intracellular trafficking. Our studies illustrate the stochastic nature of virus capsids and demonstrate the appropriation of a host protein by a virus for a non-canonical function

    On the Lyapunov functional of Leslie-Gower predator-prey models with time-delay and Holling's functional responses

    Get PDF
    The global stability on the dynamical behavior of the Leslie-Gower predator-prey system with delayed prey specific growth is analyzed by constructing the corresponding Lyapunov functional. Three different types of famous Holling's functional responses are considered in the present study. The sufficient conditions for the global stability analysis of the unique positive equilibrium point are derived accordingly. A numerical example is presented to illustrate the effect of different Holling-Type functional responses on the global stability of the Leislie-Gower predator-prey model
    • …
    corecore