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1.
本文以云杉八齿小蠹Ips typographus Linnaeus为例,经标本选取,观察虫体整体形态,绘制整体结构草图,电子显微镜观察局部、得到局部数字图像,分别建立虫体每一部分的高精度细节。把模型每部分拼装在一起组成整体模型,构建出了云杉八齿小蠹三维虚拟昆虫数字化模型。 相似文献
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AbstractIndustry 4.0 aims at providing a digital representation of a production landscape, but the challenges in building, maintaining, optimizing, and evolving digital models in inter-organizational production chains have not been identified yet in a systematic manner. In this paper, various Industry 4.0 research and technical challenges are addressed, and their present scenario is discussed. Moreover, in this article, the novel concept of developing experience-based virtual models of engineering entities, process, and the factory is presented. These models of production units, processes, and procedures are accomplished by virtual engineering object (VEO), virtual engineering process (VEP), and virtual engineering factory (VEF), using the knowledge representation technique of Decisional DNA. This blend of the virtual and physical domains permits monitoring of systems and analysis of data to foresee problems before they occur, develop new opportunities, prevent downtime, and even plan for the future by using simulations. Furthermore, the proposed virtual model concept not only has the capability of Query Processing and Data Integration for Industrial Data but also real-time visualization of data stream processing. 相似文献
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ABSTRACT The concept of digital game-based learning (DGBL) evolves rapidly together with technological enhancements of virtual reality (VR) and smart phones. However, the mental workload (MWL) that VR-training applications demand and motivational qualities originating from user experience (UX) should be identified in order to create effective and enjoyable training/learning challenges that fit with individual users’ capabilities. This study examined the effects of reality-based interaction (RBI) and VR on measures of student motivation and MWL, in a mental arithmetic game for secondary school pupils. In a randomised controlled trial with sixty school children, a mental arithmetic game was tested with three different interaction and two different presentation methods – VR RBI, VR head-mounted-display tapping and tablet flick-gesture. Results found a significant effect of RBI on MWL but no differences in enjoyment of training were found between VR-experience and tablet training-experience. In fact, adding the gaming-context to the mental arithmetic task created an enjoyable, motivating experience regardless of presentation or interaction-style. 相似文献
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超细Fe3O4粒子表面包覆酞菁钴性质研究 总被引:3,自引:1,他引:2
本文研究了合成载氧体的金属有机化学液相淀积法制造工艺,所得产物经TEM、XPS、Moss-bauer谱和B-H仪等手段,研究了它的结构和磁性能。实验表明,酞青钴以薄层形式包覆在Fe_3O_4的表面,封闭了Fe_3O_4的表面孔洞,稳定了Fe_3O_4的物相,增强了磁性能。 相似文献
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图纸数据是企业间合作需交换的一种重要的信息。本文分析了虚拟企业环境下企业之间交换图纸数据的要求,提出了一种具体的解决方案,并给出实例。 相似文献
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The behaviour of poly(3,4-butylenedioxythiophene) (PBuDOT), a relative of poly(3,4-ethylenedioxythipohnene) PEDOT within the poly(3,4-alkylenedioxythiophene) family, has been investigated at potentials above its electrochemical stability threshold using in situ ESR spectroelectrochemistry. The aim was to investigate the effect of electrochemical overoxidation on the charge carrying species, namely polarons, normally generated and annihilated during reversible redox doping and dedoping reactions, by determining the potential dependencies of spectroscopic parameters of the ESR spectra of the polymer over a selected potential range. Specific features of the trends of these dependencies allowed also for an evaluation of presence of the second type of charge carrying species—diamagnetic bipolarons and the effects of their interactions with polarons at different potentials. Around 1.5 V, where the boundary of electrochemical stability of the polymer lies, sharp drop of the concentration of paramagnetic centres has been observed together with a transitory narrowing of the ESR line. These changes were found to be irreversible as evidenced by the course of subsequent reduction half-cycle, which differed from the one for a not overoxidised polymer, observed in previous studies. Aided by the results of electrochemical studies it was concluded that the overoxidation process leads to a degradation of the polymer most probably due decrease of the conjugation length of the main chain π-bond through cross-linking or addition reactions. While the electrochemical results pointed to a non-complete degradation of the polymer, the specific parameters of the ESR line in the reduction half-cycle indicate that the remaining spins are confined to isolated segments of a partially degraded polymer where their behaviour resembles oligomer-like radicals. 相似文献
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