本文介绍了建筑信息模型BIM(building information modeling)的概念和国内外的研究状况;根据国内工程量计算的现状,分析了图形算量的利弊,提出了让造价师只做创造性劳动的设想,采用统筹e算方法,根据统筹原理全部用电算来完成算量和计价...本文介绍了建筑信息模型BIM(building information modeling)的概念和国内外的研究状况;根据国内工程量计算的现状,分析了图形算量的利弊,提出了让造价师只做创造性劳动的设想,采用统筹e算方法,根据统筹原理全部用电算来完成算量和计价工作,彻底摆脱手算和EXCEL表算,实现从施工图预算——招标控制价——投标报价——变更调整到竣工结算全过程的算量一体化,使一份工程量计算书随同图纸一传到底,以节省大量重复劳动和社会资源;同时提出了制定工程量计算规程,统一采集数据方法,统一计算式,统一表格,公开工程量计算式的一系列措施来保证;最后对"统筹e算"的使用效果进行了分析和评价。展开更多
Flower image retrieval is a very important step for computer-aided plant species recognition. In this paper, we propose an efficient segmentation method based on color clustering and domain knowledge to extract flower...Flower image retrieval is a very important step for computer-aided plant species recognition. In this paper, we propose an efficient segmentation method based on color clustering and domain knowledge to extract flower regions from flower images. For flower retrieval, we use the color histogram of a flower region to characterize the color features of flower and two shape-based features sets, Centroid-Contour Distance (CCD) and Angle Code Histogram (ACH), to characterize the shape features of a flower contour. Experimental results showed that our flower region extraction method based on color clustering and domain knowledge can produce accurate flower regions. Flower retrieval results on a database of 885 flower images collected from 14 plant species showed that our Region-of-Interest (ROI) based retrieval approach using both color and shape features can perform better than a method based on the global color histogram proposed by Swain and Ballard (1991) and a method based on domain knowledge-driven segmentation and color names proposed by Das et al.(1999).展开更多
This paper presents an automatic non-photorealistic rendering approach to generating technical illustration from 3D models. It first decomposes the 3D object into a set of CSG primitives, and then performs the hidden ...This paper presents an automatic non-photorealistic rendering approach to generating technical illustration from 3D models. It first decomposes the 3D object into a set of CSG primitives, and then performs the hidden surface removal based on the prioritized list, in which the rendition order of CSG primitives is sorted out by depth. Then, each primitive is illustrated by the pre-defined empirical lighting model, and the system mimics the stroke-drawing by user-specified style. In order to artistically and flexibly modulate the illumination, the empirical lighting model is defined by three major components: parameters of multi-level lighting intensities, parametric spatial occupations for each lighting level, and an interpolation method to calculate the lighting distribution over primitives. The stylized illustration is simulated by a grid-based method, in which we ‘fill’ the desirable pictorial units into the spatial occupation of CSG primitives, instead of “pixel-by-pixel” painting. This region-by-region shading facilitates the simulation of illustration styles.展开更多
文摘本文介绍了建筑信息模型BIM(building information modeling)的概念和国内外的研究状况;根据国内工程量计算的现状,分析了图形算量的利弊,提出了让造价师只做创造性劳动的设想,采用统筹e算方法,根据统筹原理全部用电算来完成算量和计价工作,彻底摆脱手算和EXCEL表算,实现从施工图预算——招标控制价——投标报价——变更调整到竣工结算全过程的算量一体化,使一份工程量计算书随同图纸一传到底,以节省大量重复劳动和社会资源;同时提出了制定工程量计算规程,统一采集数据方法,统一计算式,统一表格,公开工程量计算式的一系列措施来保证;最后对"统筹e算"的使用效果进行了分析和评价。
基金Project (Nos. 60302012 60202002) supported by the NationaNatural Science Foundation of China and the Research GrantCouncil of the Hong Kong Special Administrative Region (NoPolyU 5119.01E) China
文摘Flower image retrieval is a very important step for computer-aided plant species recognition. In this paper, we propose an efficient segmentation method based on color clustering and domain knowledge to extract flower regions from flower images. For flower retrieval, we use the color histogram of a flower region to characterize the color features of flower and two shape-based features sets, Centroid-Contour Distance (CCD) and Angle Code Histogram (ACH), to characterize the shape features of a flower contour. Experimental results showed that our flower region extraction method based on color clustering and domain knowledge can produce accurate flower regions. Flower retrieval results on a database of 885 flower images collected from 14 plant species showed that our Region-of-Interest (ROI) based retrieval approach using both color and shape features can perform better than a method based on the global color histogram proposed by Swain and Ballard (1991) and a method based on domain knowledge-driven segmentation and color names proposed by Das et al.(1999).
基金Project supported by the National Natural Science Foundation of China (No. 60373032), and the Returnee Foundation of EducationMinistry of China and Zhejiang Province
文摘This paper presents an automatic non-photorealistic rendering approach to generating technical illustration from 3D models. It first decomposes the 3D object into a set of CSG primitives, and then performs the hidden surface removal based on the prioritized list, in which the rendition order of CSG primitives is sorted out by depth. Then, each primitive is illustrated by the pre-defined empirical lighting model, and the system mimics the stroke-drawing by user-specified style. In order to artistically and flexibly modulate the illumination, the empirical lighting model is defined by three major components: parameters of multi-level lighting intensities, parametric spatial occupations for each lighting level, and an interpolation method to calculate the lighting distribution over primitives. The stylized illustration is simulated by a grid-based method, in which we ‘fill’ the desirable pictorial units into the spatial occupation of CSG primitives, instead of “pixel-by-pixel” painting. This region-by-region shading facilitates the simulation of illustration styles.
