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141.
Jiawei Huang Mahda M. Bagher Heather Dohn Ross Nathan Piekielek Jan Oliver Wallgrün Jiayan Zhao 《Journal of Map & Geography Libraries》2018,14(1):40-63
Libraries have been the key to preserving culture and historic legacy for centuries. One such treasure cataloged in The Pennsylvania State University (Penn State) Libraries is a collection of over 33,000 Sanborn? Fire Insurance Maps. Originally kept safe in metal drawers, the library has embarked on a journey to digitize this abundance of information, combine it with other media such as photographs, and make it accessible through a web interface. Inspired by these efforts, we accessed this information and took it to the next level. Using state of the art 3D modeling and immersive technologies, we created a historic 3D model and immersive experiences of Penn State, exemplarily for the 1922 campus. The resulting experiences can be accessed through the web but also through head mounted displays (HMDs) and mobile phones in combination with VR viewers such as the Google Cardboard. Additionally, they can be used anywhere in the world or on the campus itself as a way to enable remote and in situ experiences and learning. Immersive experiences let us connect to the past, the present and the future, and as such offer value to digital cultural heritage efforts. 相似文献
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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
144.
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
145.
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
146.
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
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149.
论Web2.0下网络文化的传播 总被引:1,自引:0,他引:1
Web2.0 是相对于Webl.0的新一代互联网应用的统称,它强调用户的广泛参与,正是由于这种特点,使其在短短的几年内得到飞速的发展.但是随着Web2.0的广泛应用,也出现很多问题.本文从Web2.0下网络文化的特点展开,探讨了Web2.0下网络文化传播中存在的问题,并从技术、道德、法律三个方面提出了Web2.0下的网络文化的监管模式. 相似文献
150.
完善我国创业投资税收优惠制度的思考 总被引:2,自引:0,他引:2
合法合理的税收优惠制度是创业投资蓬勃发展的关键因素和必要前提.我国政府应扮演制度设计和严格征管的角色.借鉴国际经验.从税收优惠体系、优惠环节、优惠方式、优惠对象、优惠税种等各个方面来完善我国创业投资税收优惠制度. 相似文献