Discrete Level of Detail (LOD) strategy is an effective solution for balancing the inherentcontradiction between quality and speed in computer graphics. However, application ofthis strategy requires both the appropria...Discrete Level of Detail (LOD) strategy is an effective solution for balancing the inherentcontradiction between quality and speed in computer graphics. However, application ofthis strategy requires both the appropriate selection approach and the visually comfortable transition procedure to reduce the popping effects introduced by switching betweendifferent levels. In this paper, a novel automatic LOD selection method based on viewpoint entropy was proposed. Firstly, the traditional calculation method of viewpointentropy contained in a scene was improved for the preprocessing of LOD models. Then,the runtime rendering scheme combined with our selection method was designed forbalance of frame rate during real-time rendering, and a novel smoothing LOD transitionstrategy based on Alternate Frame Rendered (ALR) was put forward for eliminationof popping effects. Finally, an example of complex scene combined with our proposalwas researched to verify its real-time performance and ability in holding continuity ofrendered images. Experimental studies show the effectiveness for stabilizing frame rateand improvements in reducing loss of continuity.展开更多
Since the 1980s, the Chinese economy has developed rapidly, with an av- erage annual growth rate around 10%. Energy consumption in China has greatly in- creased as well. This paper investigates the relationship betwee...Since the 1980s, the Chinese economy has developed rapidly, with an av- erage annual growth rate around 10%. Energy consumption in China has greatly in- creased as well. This paper investigates the relationship between energy consumption, economic development and temperature in China by adopting provincial panel data from 1990 to 2011. Different from existing studies, in this paper, we use a panel smooth transition regression （PSTR） model to estimate the non-linearity relationship. Four different threshold variables including two lagged endogenous variables and two important exogenous variables have been considered. We find that energy intensity and the ratio of gross capital formation are suitable for the non-linearity model. The estimated elasticities of time dynamic indicate that energy consumption is income in- elastic and temperature inelastic. Elasticities of real income at first increase and then decrease, however, elasticities of temperature gradually increase after the year 1993. Last of all, we propose some policy implications.展开更多
文摘Discrete Level of Detail (LOD) strategy is an effective solution for balancing the inherentcontradiction between quality and speed in computer graphics. However, application ofthis strategy requires both the appropriate selection approach and the visually comfortable transition procedure to reduce the popping effects introduced by switching betweendifferent levels. In this paper, a novel automatic LOD selection method based on viewpoint entropy was proposed. Firstly, the traditional calculation method of viewpointentropy contained in a scene was improved for the preprocessing of LOD models. Then,the runtime rendering scheme combined with our selection method was designed forbalance of frame rate during real-time rendering, and a novel smoothing LOD transitionstrategy based on Alternate Frame Rendered (ALR) was put forward for eliminationof popping effects. Finally, an example of complex scene combined with our proposalwas researched to verify its real-time performance and ability in holding continuity ofrendered images. Experimental studies show the effectiveness for stabilizing frame rateand improvements in reducing loss of continuity.
基金The authors thank the reviewers for their careful reading and provid- ing some pertinent suggestions. The research is supported by the National Natural Science Foundation of China （No. 71073009 ）, Chinese science and technology supporting program （No. 2012BAC20B08） and Tianjin City High School Science ＆ Technology Fund Planning Project （No. 20130823）.
文摘Since the 1980s, the Chinese economy has developed rapidly, with an av- erage annual growth rate around 10%. Energy consumption in China has greatly in- creased as well. This paper investigates the relationship between energy consumption, economic development and temperature in China by adopting provincial panel data from 1990 to 2011. Different from existing studies, in this paper, we use a panel smooth transition regression （PSTR） model to estimate the non-linearity relationship. Four different threshold variables including two lagged endogenous variables and two important exogenous variables have been considered. We find that energy intensity and the ratio of gross capital formation are suitable for the non-linearity model. The estimated elasticities of time dynamic indicate that energy consumption is income in- elastic and temperature inelastic. Elasticities of real income at first increase and then decrease, however, elasticities of temperature gradually increase after the year 1993. Last of all, we propose some policy implications.
