113 research outputs found

    Agent and cyber-physical system based self-organizing and self-adaptive intelligent shopfloor

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    The increasing demand of customized production results in huge challenges to the traditional manufacturing systems. In order to allocate resources timely according to the production requirements and to reduce disturbances, a framework for the future intelligent shopfloor is proposed in this paper. The framework consists of three primary models, namely the model of smart machine agent, the self-organizing model, and the self-adaptive model. A cyber-physical system for manufacturing shopfloor based on the multiagent technology is developed to realize the above-mentioned function models. Gray relational analysis and the hierarchy conflict resolution methods were applied to achieve the self-organizing and self-adaptive capabilities, thereby improving the reconfigurability and responsiveness of the shopfloor. A prototype system is developed, which has the adequate flexibility and robustness to configure resources and to deal with disturbances effectively. This research provides a feasible method for designing an autonomous factory with exception-handling capabilities

    Research on vibration characteristics of a multi-barrel artillery

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    The vibration of the barrel, induced by the interaction with a high-speed moving projectile, has a considerable influence on the shooting accuracy of a weapon. The finite element model of a multi-barrel was established with the goal to investigate its vibration characteristics in this paper, and the natural frequency and mode shape were analyzed by finite element method. To verify the result of finite element modal analysis (FEMA), a modal testing system basis on SC310W multi-path data-collecting system and hammer hitting method was set up. Results show that the low order vibrations of the multi-barrel artillery were mainly vertical, horizontal and torsional vibration, but the local vibration at high orders. The error of natural frequencies between the results obtained by simulation and test was 8.82 % in the first mode frequency and 1.37 % in the eighth. The FEMA can effectively simulate the actual vibration of the multi-barrel artillery

    Agent and Cyber-Physical System Based Self-Organizing and Self-Adaptive Intelligent Shopfloor

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    Efficient Deep Reinforcement Learning via Adaptive Policy Transfer

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    Transfer Learning (TL) has shown great potential to accelerate Reinforcement Learning (RL) by leveraging prior knowledge from past learned policies of relevant tasks. Existing transfer approaches either explicitly computes the similarity between tasks or select appropriate source policies to provide guided explorations for the target task. However, how to directly optimize the target policy by alternatively utilizing knowledge from appropriate source policies without explicitly measuring the similarity is currently missing. In this paper, we propose a novel Policy Transfer Framework (PTF) to accelerate RL by taking advantage of this idea. Our framework learns when and which source policy is the best to reuse for the target policy and when to terminate it by modeling multi-policy transfer as the option learning problem. PTF can be easily combined with existing deep RL approaches. Experimental results show it significantly accelerates the learning process and surpasses state-of-the-art policy transfer methods in terms of learning efficiency and final performance in both discrete and continuous action spaces.Comment: Accepted by IJCAI'202

    Multimodality Molecular Imaging of Cardiovascular Disease Based on Nanoprobes

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    Recently, multimodality molecular imaging has evolved into a fast-growing research field with goals of detecting and measuring biological processes in vivo non-invasively. Researchers have come to realize that the complementary abilities of different imaging modalities over single modality could provide more precisely information for the diagnosis of diseases. At present, nanoparticles-based multimodal imaging probes have received significant attention because of their ease of preparation and straightforward integration of each modality into one entity. More importantly, nanotechnology has an increasing impact on multimodality molecular imaging of cardiovascular diseases, such as atherosclerosis and vulnerable plaque, myocardial infarction, angiogenesis, apoptosis and so on. In this review, we briefly summarize that various nanoprobes are exploited for targeted molecular imaging of cardiovascular diseases, as well as associated multimodality imaging approaches and their applications in the diagnosis and treatment of cardiovascular diseases

    Construction and immunological characterization of CD40L or GM-CSF incorporated Hantaan virus like particle

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    Infection of Hantaan virus (HTNV) usually causes hemorrhagic fever with renal syndrome (HFRS). China has the worst epidemic incidence of HFRS as well as high fatality. Inactivated whole virus has been used for HFRS vaccination, however there are still problems such as safety concerns. CD40 ligand (CD40L) and granulocyte macrophage colony-stimulating factor (GM-CSF) are well-known immune stimulating molecules that can enhance antigen presenting, lymphocytes activation and maturation, incorporation of CD40L and GM-CSF to the surface of virus like particles (VLPs) can greatly improve the vaccination effect. We constructed eukaryotic vectors expressing HTNV M segment and S segment, as well as vectors expressing HTNV M segment with CD40L or GM-CSF, our results showed successful production of CD40L or GM-CSF incorporated HTNV VLPs. In vitro stimulation with CD40L or GM-CSF anchored HTNV VLP showed enhanced activation of macrophages and DCs. CD40L/GM-CSF incorporated VLP can induce higher level of HTNV specific antibody and neutralizing antibody in mice. Immunized mice splenocytes showed higher ability of secreting IFN-γ and IL-2, as well as enhancing CTL activity. These results suggest CD40L/GM-CSF incorporated VLP can serve as prospective vaccine candidate

    Clinical and Epidemiologic Research Ethnic Variation in Early Age-Related Macular Degeneration Lesions Between White Australians and Singaporean Asians

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    Citation: Joachim N, Mitchell P, Younan C, et al. Ethnic variation in early age-related macular degeneration lesions between white Australians and Singaporean Asians. Invest Ophthalmol Vis Sci. 2014;55:4421-4429. DOI:10.1167/iovs.14-14476 PURPOSE. We compared early age-related macular degeneration (AMD) lesion characteristics between white Australians and Singaporean Asians. METHODS. Participants of the Blue Mountains Eye Study (BMES; whites, n ¼ 3508) and the Singapore Epidemiology of Eye Disease Study (SEED; Malay, n ¼ 3280, Indian, n ¼ 3400, and Chinese, n ¼ 3353) underwent examinations, including retinal photography. The AMD lesions were assessed following the Wisconsin AMD grading protocol by the same photographic grader. Prevalence and characteristics of early AMD lesions were compared between the BMES and the SEED. The associations between ethnicity and early AMD lesion types were analyzed using logistic regression models adjusting for age, sex, smoking status, lipids, and genetic polymorphisms associated with AMD. RESULTS. After age-standardization to the BMES population, the prevalence of distinct soft drusen was significantly higher in Singaporeans compared to Australians (23.9%, 95% confidence interval [CI] 22.9-25.0 vs. 6.2%, 95% CI 5.3-7.0), with an adjusted odds ratio (OR) of 4.6 (95% CI 3.4-6.0). In contrast, the prevalence of indistinct soft or reticular drusen was significantly lower in Singaporeans compared to Australians (6.5%, 95% CI 5.9-7.1 vs. 8.3%, 95% CI 7.4-9.3, with nonsignificant adjusted OR of 1.2, 95% CI 0.8-1.7). Soft drusen of any type were present frequently at the inner and outer macula (within a zone ‡500 to <3000 lm radius from the foveal center) among Singaporeans, while among Australians soft drusen were present more frequently at the central macula (<500 lm radius). CONCLUSIONS. Singaporean Asians had a milder spectrum of early AMD lesions and lesion characteristics (predominantly distinct soft drusen and noncentral location) compared to white Australians
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