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91.
近年来中国移动阅读产值井喷式增长,市场格局明朗化,为谋求更好发展,企业亟须创新盈利模式.论文以IP生态为视域,从产业链的构成要素切入,探讨产业盈利模式的创新策略,得出如下几点:以知识付费为主的类众筹模式、以IP运营为核心的泛娱乐模式、以社交为切入点的阅读轻社交模式、以人工智能科技为契合点的定制化盈利模式、以原生广告为主的新型广告模式. 相似文献
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93.
匿名评审已经逐渐成为中国博士学位论文评价的主流方式。由于匿名制度规避了评审的人情因素和偏见因素,总体来讲是有效的。但匿名评审也存在系统性缺陷,包括完全匿名不现实、专家遴选不匹配、评价过程不稳定、评价结果不确切、评价导向不合理等,当前很多学校实施的一票否决制又极大地放大了匿名评审的缺陷。因此,一方面要完善博士学位论文的匿名评审制度,规范盲审结果的使用,完善评审的复审程序,建立权责匹配的评审机制,加强匿名评审与公开评审的结合;另一方面,还要全面构建系统的质量保障体系,前移质量关口,完善博士培养的全过程。 相似文献
94.
Earth''s known supercontinents are believed to have formed in vastly different ways, with two endmembers being introversion and extroversion. The former involves the closure of the internal oceans formed during the break-up of the previous supercontinent, whereas the latter involves the closure of the previous external superocean. However, it is unclear what caused such diverging behavior of supercontinent cycles that involved first-order interaction between subducting tectonic plates and the mantle. Here we address this question through 4D geodynamic modeling using realistic tectonic set-ups. Our results show that the strength of the oceanic lithosphere plays a critical role in determining the assembly path of a supercontinent. We found that high oceanic lithospheric strength leads to introversion assembly, whereas lower strength leads to extroversion assembly. A theoretically estimated reduction in oceanic crustal thickness, and thus its strength, during Earth''s secular cooling indicates that introversion was only possible for the Precambrian time when the oceanic lithosphere was stronger, thus predicting the assembling of the next supercontinent Amasia through the closure of the Pacific Ocean instead of the Indian-Atlantic oceans. Our work provides a new understanding of the secular evolution of plate tectonics and geodynamics as the Earth cooled. 相似文献
95.
Rui Li Cong Zhang Jiawen Li Yachao Zhang Shunli Liu Yanlei Hu Shaojun Jiang Chao Chen Chen Xin Yuan Tao Bin Dong Dong Wu Jiaru Chu 《国家科学评论(英文版)》2022,9(11)
Inspired by origami/kirigami, three-dimensional (3D) mesostructures assembled via a mechanics-guided approach, with reversible and maneuverable shape-morphing capabilities, have attracted great interest with regard to a broad range of applications. Despite intensive studies, the development of morphable 3D mesostructures with high-order (multi-degree-of-freedom) deformation and untethered high-frequency actuation remains challenging. This work introduces a scheme for a magnetically encoded transferable 3D mesostructure, with polyethylene terephthalate (PET) film as the skeleton and discrete magnetic domains as actuation units, to address this challenge. The high-order deformation, including hierarchical, multidirectional and blending shape morphing, is realized by encoding 3D discrete magnetization profiles on the architecture through ultraviolet curing. Reconfigurable 3D mesostructures with a modest structural modulus (∼3 GPa) enable both high-frequency (∼55 Hz) and large-deformation (∼66.8%) actuation under an alternating magnetic field. Additionally, combined with the shape-retention and adhesion property of PET, these 3D mesostructures can be readily transferred and attached to many solid substrates. On this basis, diverse functional devices, including a switchable colour letter display, liquid mixer, sequential flashlight and biomimetic sliding robot, are demonstrated to offer new perspectives for robotics and microelectronics. 相似文献
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97.
Temperature probes onboard the Chang’E-4 (CE-4) spacecraft provide the first in situ regolith temperature measurements from the far side of the Moon. We present these temperature measurements with a customized thermal model and reveal the particle size of the lunar regolith at the CE-4 landing site to be ∼15 μm on average over depth, which indicates an immature regolith below the surface. In addition, the conductive component of thermal conductivity is measured as ∼1.53 × 10–3 W m–1 K–1 on the surface and ∼8.48 × 10–3 W m–1 K–1 at a depth of 1 m. The average bulk density is ∼471 kg m–3 on the surface and ∼824 kg m–3 in the upper 30 cm of the lunar regolith. These thermophysical properties provide important additional ‘ground truth’ at the lunar far side, which is critical for the future analysis and interpretation of global temperature observations. 相似文献
98.
传统节庆旅游资源是我国最具特色的旅游资源之一,发展节庆旅游对于丰富旅游产品和发展旅游业具有着重用意义。本文给出了节庆旅游的概念,指出了节庆旅游的作用,并对我国发展节庆旅游做了具体的SWOT分析,在此基础上提出了我国节庆旅游的发展对策。 相似文献
99.
在独立学院新型办学机制与模式下,会计模拟实验室在会计教学体系中的作用和地位显得尤为重要。本文从会计教学软硬件二维结构图出发,提出会计模拟实验是新时期会计教学的热点,会计模拟实验室建设是经济管理专业实验室建设的起点,并在此基础上探讨了会计模拟实验教学和会计模拟实验室建设过程中可能出现的误区和归避的方法。 相似文献
100.