针对场景切换时产生的LOD(level of detail)纹理突变和走样问题,提出一种基于着色器的LOD纹理混合与反走样平滑过渡算法。该算法根据三维模型和视点的距离,运用基于Alpha测试的不透明蒙版算法和加权邻帧反走样算法,在LOD间生成过渡材质...针对场景切换时产生的LOD(level of detail)纹理突变和走样问题,提出一种基于着色器的LOD纹理混合与反走样平滑过渡算法。该算法根据三维模型和视点的距离,运用基于Alpha测试的不透明蒙版算法和加权邻帧反走样算法,在LOD间生成过渡材质,实现三维模型LOD切换的平滑过渡,不仅能够改善纹理质量,而且能够保证三维场景加载的流畅性与真实性。实验结果表明,与UnrealEngine4(UE4)自带的平滑算法相比,算法的GPU平均耗时减少8%以上,帧率提高8%以上。与现有纹理平滑过渡方法相比,该算法能够优化GPU渲染性能,稳定并提高画面帧率,保持良好的视觉效果,有效地解决LOD层级切换时的突变问题。展开更多
The Dongfengnanshan Cu polymetallic deposit is one representative deposit of the Tianbaoshan ore district in the Yanbian area, northeast(NE) China. There occur two types of ore bodies in this deposit, the stratiform o...The Dongfengnanshan Cu polymetallic deposit is one representative deposit of the Tianbaoshan ore district in the Yanbian area, northeast(NE) China. There occur two types of ore bodies in this deposit, the stratiform ore bodies and veintype ones, controlled by the Early Permian strata and the Late Hercynian diorite intrusion, respectively. Due to the ambiguous genetic type of the stratiform ore bodies, there has been controversy on the relationship between them and veintype ore bodies. To determine the genetic type of stratiform ore bodies, laser ablation inductively coupled plasma mass spectrometry(LA-ICP-MS) in situ trace elements and S–Pb isotope analysis have been carried on the sulfides in the stratiform ore bodies. Compared with that in skarn, Mississippi Valley-type(MVT), and epithermal deposits, sphalerite samples in the stratiform ore bodies of the Dongfengnanshan deposit are significantly enriched in Fe, Mn, and In, while depleted in Ga, Ge, and Cd, which is similar to the sphalerite in volcanic-associated massive sulfide(VMS) deposits. Co/Ni ratio of pyrrhotites in the stratiform ore bodies is similar to that in VMS-type deposits. The concentrations of Zn and Cd of chalcopyrites are similar to those of recrystallized VMS-type deposits. These characteristics also reflect the intermediate ore-forming temperature of the stratiform ore bodies in this deposit. Sulfur isotope compositions of sulfides are similar to those of VMS-type deposits, reflecting that sulfur originated from the Permian Miaoling Formation. Lead isotope compositions indicate mixed-source for lead. Moreover, the comparison of the Dongfengnanshan stratiform ore bodies with some VMStype deposits in China and abroad, on the trace elements and S–Pb isotope characteristics of the sulfides reveals that the stratiform ore bodies of the Dongfengnanshan deposit belong to the VMS-type, and have closely genetic relationship with the early Permian marine volcanic sedimentary rocks.展开更多
天地一体化网络是一个天、空、地多种网络组成的复杂异构网络,其中临近空间飞行器具有灵活性强、载荷大、运营维护成本低、滞空时间长等特点,是天地一体化网络中不可或缺的一部分.但在当前主流网络架构设计中,对临近空间飞行器研究定位...天地一体化网络是一个天、空、地多种网络组成的复杂异构网络,其中临近空间飞行器具有灵活性强、载荷大、运营维护成本低、滞空时间长等特点,是天地一体化网络中不可或缺的一部分.但在当前主流网络架构设计中,对临近空间飞行器研究定位不足,也没有结合应用对其协议架构进行针对性分析.提出了一种基于天地一体化网络体系架构的临近空间接入网,可以根据需要在热点区域或应急情况下临时布设,具有很大灵活性,能作为卫星系统的有效补充.给出了分层自治域网络模型,分析了临近空间接入网典型应用,从实际应用需求出发对网络层、数据链路层和物理层进行了协议设计.网络层采用分层结构网络,通过网络分群,可以最优化网络资源利用,实现动态组网.数据链路层结合物理层进行一体化设计,将信道划分成两部分,分别采用SPMA(Statistical Priority-Based Multiple Access)协议和DTDMA(Dynamic Time Division Multiple Access)协议,保证不同业务的QoS(Quality of Service)需求.展开更多
文摘针对场景切换时产生的LOD(level of detail)纹理突变和走样问题,提出一种基于着色器的LOD纹理混合与反走样平滑过渡算法。该算法根据三维模型和视点的距离,运用基于Alpha测试的不透明蒙版算法和加权邻帧反走样算法,在LOD间生成过渡材质,实现三维模型LOD切换的平滑过渡,不仅能够改善纹理质量,而且能够保证三维场景加载的流畅性与真实性。实验结果表明,与UnrealEngine4(UE4)自带的平滑算法相比,算法的GPU平均耗时减少8%以上,帧率提高8%以上。与现有纹理平滑过渡方法相比,该算法能够优化GPU渲染性能,稳定并提高画面帧率,保持良好的视觉效果,有效地解决LOD层级切换时的突变问题。
基金supported by the National Natural Science Foundation of China (NSFC) (No. 41772062)
文摘The Dongfengnanshan Cu polymetallic deposit is one representative deposit of the Tianbaoshan ore district in the Yanbian area, northeast(NE) China. There occur two types of ore bodies in this deposit, the stratiform ore bodies and veintype ones, controlled by the Early Permian strata and the Late Hercynian diorite intrusion, respectively. Due to the ambiguous genetic type of the stratiform ore bodies, there has been controversy on the relationship between them and veintype ore bodies. To determine the genetic type of stratiform ore bodies, laser ablation inductively coupled plasma mass spectrometry(LA-ICP-MS) in situ trace elements and S–Pb isotope analysis have been carried on the sulfides in the stratiform ore bodies. Compared with that in skarn, Mississippi Valley-type(MVT), and epithermal deposits, sphalerite samples in the stratiform ore bodies of the Dongfengnanshan deposit are significantly enriched in Fe, Mn, and In, while depleted in Ga, Ge, and Cd, which is similar to the sphalerite in volcanic-associated massive sulfide(VMS) deposits. Co/Ni ratio of pyrrhotites in the stratiform ore bodies is similar to that in VMS-type deposits. The concentrations of Zn and Cd of chalcopyrites are similar to those of recrystallized VMS-type deposits. These characteristics also reflect the intermediate ore-forming temperature of the stratiform ore bodies in this deposit. Sulfur isotope compositions of sulfides are similar to those of VMS-type deposits, reflecting that sulfur originated from the Permian Miaoling Formation. Lead isotope compositions indicate mixed-source for lead. Moreover, the comparison of the Dongfengnanshan stratiform ore bodies with some VMStype deposits in China and abroad, on the trace elements and S–Pb isotope characteristics of the sulfides reveals that the stratiform ore bodies of the Dongfengnanshan deposit belong to the VMS-type, and have closely genetic relationship with the early Permian marine volcanic sedimentary rocks.
文摘天地一体化网络是一个天、空、地多种网络组成的复杂异构网络,其中临近空间飞行器具有灵活性强、载荷大、运营维护成本低、滞空时间长等特点,是天地一体化网络中不可或缺的一部分.但在当前主流网络架构设计中,对临近空间飞行器研究定位不足,也没有结合应用对其协议架构进行针对性分析.提出了一种基于天地一体化网络体系架构的临近空间接入网,可以根据需要在热点区域或应急情况下临时布设,具有很大灵活性,能作为卫星系统的有效补充.给出了分层自治域网络模型,分析了临近空间接入网典型应用,从实际应用需求出发对网络层、数据链路层和物理层进行了协议设计.网络层采用分层结构网络,通过网络分群,可以最优化网络资源利用,实现动态组网.数据链路层结合物理层进行一体化设计,将信道划分成两部分,分别采用SPMA(Statistical Priority-Based Multiple Access)协议和DTDMA(Dynamic Time Division Multiple Access)协议,保证不同业务的QoS(Quality of Service)需求.
