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林业专题图位图数据的处理方法
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作者 范文义 王治富 +2 位作者 樊凤艳 孙宝良 朱峰 《东北林业大学学报》 CAS CSCD 北大核心 1996年第2期27-31,共5页
为了进一步完善林业专题图系统,实现常用专题图的快速显示,文章研究了位图数据在计算机的显示缓冲区中的组织结构。通过对显示缓冲区寄存器的正确控制,完成对位图数据的读写操作,读操作存贮该位图数据并形成磁盘数据文件;写操作将所形... 为了进一步完善林业专题图系统,实现常用专题图的快速显示,文章研究了位图数据在计算机的显示缓冲区中的组织结构。通过对显示缓冲区寄存器的正确控制,完成对位图数据的读写操作,读操作存贮该位图数据并形成磁盘数据文件;写操作将所形成的磁盘数据文件直接写入显示缓冲区,恢复屏幕图形。程序用 Microsoft C 5.0和 Microsoft 宏汇编5.0语言编写。运行结果表明,用专题图系统程序输出一幅复杂的专题图需20~30min,而用文章所述的方法恢复一幅相应的专题图不超过5s。 展开更多
关键词 林业专题图 位图数据 VRAM
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基于Excel自动化技术的位图数据分析系统的设计与实现
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作者 李强 陈遵德 《顺德职业技术学院学报》 2004年第1期40-42,共3页
初步分析位图数据分析系统的基本功能、总体结构,阐述基于 Excel 自动化技术的位图数据分析系统的实现方法,以及实现此系统的技术要点——如何使用 C++Build-er 6的图像功能和 Excel 自动化功能。
关键词 位图数据分析 EXCEL自动化 C++ BUILDER 6
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三维打印快速成形系统中的数据压缩方法 被引量:1
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作者 刘厚才 莫健华 叶春生 《华中科技大学学报(自然科学版)》 EI CAS CSCD 北大核心 2008年第5期90-92,共3页
设计了一种基于字节压缩的位图数据压缩方法.根据三维打印快速成形中位图数据的特点,本压缩方法分别采用1个byte、2个byte和4个byte来表示压缩数据.该压缩方法的压缩比较高,经过对多个CAD模型切片后所得位图数据的压缩前后数据大小的比... 设计了一种基于字节压缩的位图数据压缩方法.根据三维打印快速成形中位图数据的特点,本压缩方法分别采用1个byte、2个byte和4个byte来表示压缩数据.该压缩方法的压缩比较高,经过对多个CAD模型切片后所得位图数据的压缩前后数据大小的比较,发现最小压缩比为12.1∶1,最大达53.9∶1,压缩效果比较理想.本方法在对数据进行压缩和解压的过程中,不需要复杂的计算,速度快,耗时少,对三维打印快速成形机这种有上千层位图数据需要处理的场合不会构成瓶颈,可以较好地满足三维打印快速成形系统的要求. 展开更多
关键词 快速成形 三维打印 位图数据 数据压缩 压缩单元 压缩比
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Windows位图和Leptonica位图的转换
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作者 袁智勇 刘文林 《科技创新导报》 2019年第30期113-114,共2页
很多屏幕文字识别应用把截屏后的数据保存为图片文件,然后从硬盘上读取图片文件进行文字识别,这种做法效率很低。本文介绍了Windows位图和Leptonica位图格式的不同特点,提出了一套简便的,在内存中进行转换的方法。这使得直接在内存中识... 很多屏幕文字识别应用把截屏后的数据保存为图片文件,然后从硬盘上读取图片文件进行文字识别,这种做法效率很低。本文介绍了Windows位图和Leptonica位图格式的不同特点,提出了一套简便的,在内存中进行转换的方法。这使得直接在内存中识别文字成为可能,省去在硬盘上存取图片文件的步骤,从而大大提高屏幕文字识别应用的效率。 展开更多
关键词 屏幕文字识别 tesseract leptonica GDI+ 位图数据转换
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手写短信实现方法
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作者 钱鹏鹤 《信息与电子工程》 2007年第2期103-103,共1页
目前市场上有各种具有触摸屏的移动通信终端设备,用户可以使用特殊的笔在触摸屏上直接书写。这些设备中包含一些识别模块(软件,硬件),可以识别出用户书写的是什么字符,然后再将该字符输入到一个编辑对话框或编辑区域中。在触摸屏... 目前市场上有各种具有触摸屏的移动通信终端设备,用户可以使用特殊的笔在触摸屏上直接书写。这些设备中包含一些识别模块(软件,硬件),可以识别出用户书写的是什么字符,然后再将该字符输入到一个编辑对话框或编辑区域中。在触摸屏上书写,信息采集单元从触摸屏上获取输入的数据,这些数据是位图数据,识别模块再将这些位图数据识别为字符。因此,识别模块的识别能力, 展开更多
关键词 通信终端设备 识别模块 字符输入 短信 手写 信息采集单元 位图数据 触摸屏
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A method for improving graph queries processing using positional inverted index (P.I.I) idea in search engines and parallelization techniques 被引量:2
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作者 Hamed Dinari Hassan Naderi 《Journal of Central South University》 SCIE EI CAS CSCD 2016年第1期150-159,共10页
The idea of positional inverted index is exploited for indexing of graph database. The main idea is the use of hashing tables in order to prune a considerable portion of graph database that cannot contain the answer s... The idea of positional inverted index is exploited for indexing of graph database. The main idea is the use of hashing tables in order to prune a considerable portion of graph database that cannot contain the answer set. These tables are implemented using column-based techniques and are used to store graphs of database, frequent sub-graphs and the neighborhood of nodes. In order to exact checking of remaining graphs, the vertex invariant is used for isomorphism test which can be parallel implemented. The results of evaluation indicate that proposed method outperforms existing methods. 展开更多
关键词 graph query processing frequent subgraph graph mining data mining positional inverted index
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Effect of Uncertainty of Grid DEM on TOPMODEL:Evaluation and Analysis 被引量:1
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作者 WANG Peifa DU Jinkang +1 位作者 FENG Xuezhi KANG Guoding 《Chinese Geographical Science》 SCIE CSCD 2006年第4期320-326,共7页
TOPMODEL,a semi-distributed hydrological model,has been widely used.In the process of simulation of the model,Digital Elevation Model(DEM) is used to provide the input data,such as topographic index and distance to th... TOPMODEL,a semi-distributed hydrological model,has been widely used.In the process of simulation of the model,Digital Elevation Model(DEM) is used to provide the input data,such as topographic index and distance to the drainage outlet;thus DEM plays an important role in TOPMODEL.This study aims at examining the impacts of DEM uncertainty on the simulation results of TOPMODEL.In this paper,the effects were evaluated mainly from quantitative and qualitative aspects.Firstly,DEM uncertainty was simulated by using the Monte Carlo method,and for every DEM realization,the topographic index and distance to the drainage outlet were extracted.Secondly,the obtained topographic index and the distance to the drainage outlet were input to the TOPMODEL to simulate seven rain-storm-flood events,and four evaluation indices,such as Nash and Sutcliffe efficiency criterion(EFF),sum of squared residuals over all time steps(SSE),sum of squared log residuals over all time steps(SLE) and sum of absolute errors over all time steps(SAE) were recorded.Thirdly,these four evaluation indices were analyzed in statistical manner(minimum,maximum,range,standard deviation and mean value),and effect of DEM uncertainty on TOPMODEL was quantitatively analyzed.Finally,the simulated hydrographs from TOPMODEL using the original DEM and realizations of DEM were qualitatively evaluated under each flood cases.Results show that the effect of DEM uncertainty on TOPMODEL is inconsiderable and could be ignored in the model’s application.This can be explained by:1) TOPMODEL is not sensitive to the distribution of topographic index and distance to the drainage outlet;2) the distri-bution of topographic index and distance to the drainage outlet are slightly affected by DEM uncertainty. 展开更多
关键词 DEM uncertainty TOPMODEL Monte Carlo simulation Jiaokou watershed
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Modified image analytical solutions for ground displacement using nonuniform convergence model 被引量:9
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作者 杨小礼 黄阜 王金明 《Journal of Central South University》 SCIE EI CAS 2011年第3期859-865,共7页
Based on the image theory,the analytical solutions of tunneling-induced ground displacement were derived in conjunction with the nonuniform convergence model.The reasonable value of Poisson ratio in the analytical sol... Based on the image theory,the analytical solutions of tunneling-induced ground displacement were derived in conjunction with the nonuniform convergence model.The reasonable value of Poisson ratio in the analytical solution was discussed.The ground settlement width parameter which could reflect the ground condition was introduced to modify the analytical solutions proposed above,and new analytical solutions were presented.To evaluate the validity of the present solutions using the nonuniform convergence model,the results were compared with the observed values for four engineering projects,including 38 measured data of ground settlement.The agreement shows that the present solutions using the nonuniform convergence model are effective for evaluating the tunneling-induced ground displacements. 展开更多
关键词 subway tunnel ground displacement image method ground settlement width parameter
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A two-step rectification algorithm for airborne linear images with POS data
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作者 庹红娅 刘允才 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2005年第6期492-496,共5页
Rectification for airborne linear images is an indispensable preprocessing step. This paper presents in detail a two-step rectification algorithm. The first step is to establish the model of direct georeference positi... Rectification for airborne linear images is an indispensable preprocessing step. This paper presents in detail a two-step rectification algorithm. The first step is to establish the model of direct georeference position using the data provided by the Po- sitioning and Orientation System (POS) and obtain the mathematical relationships between the image points and ground reference points. The second step is to apply polynomial distortion model and Bilinear Interpolation to get the final precise rectified images. In this step, a reference image is required and some ground control points (GCPs) are selected. Experiments showed that the final rectified images are satisfactory, and that our two-step rectification algorithm is very effective. 展开更多
关键词 Airborne linear image POS data Two-step rectification algorithm Direct georeference position Polynomial dis- tortion model
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Mining Data Correlation from Multi-Faceted Sensor Data in Internet of Things 被引量:1
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作者 曹栋 乔秀全 +2 位作者 Judith Gelernter 李晓峰 孟洛明 《China Communications》 SCIE CSCD 2011年第1期132-138,共7页
Sensors are ubiquitous in the Internet of Things for measuring and collecting data. Analyzing these data derived from sensors is an essential task and can reveal useful latent information besides the data. Since the I... Sensors are ubiquitous in the Internet of Things for measuring and collecting data. Analyzing these data derived from sensors is an essential task and can reveal useful latent information besides the data. Since the Internet of Things contains many sorts of sensors, the measurement data collected by these sensors are multi-type data, sometimes contai- ning temporal series information. If we separately deal with different sorts of data, we will miss useful information. This paper proposes a method to dis- cover the correlation in multi-faceted data, which contains many types of data with temporal informa- tion, and our method can simultaneously deal with multi-faceted data. We transform high-dimensional multi-faeeted data into lower-dimensional data which is set as multivariate Gaussian Graphical Models, then mine the correlation in multi-faceted data by discover the structure of the multivariate Gausslan Graphical Models. With a real data set, we verifies our method, and the experiment demonstrates that the method we propose can correctly fred out the correlation among multi-faceted meas- urement data. 展开更多
关键词 multi-faceted data SENSORS Internet of Things Gaussian Graphical Models
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Application of Dempster-Shafer theory in mineral resource potential mapping
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作者 CHEN Yong-liang WU Wei LI Xue-bin 《Journal of Geoscientific Research in Northeast Asia》 2005年第1期104-115,共12页
The Dempster-Shafer theory has been successfully applied to mineral resource potential mapping in GIS environmental. In this applied form, basic probability assignment and combined basic probability assignment are app... The Dempster-Shafer theory has been successfully applied to mineral resource potential mapping in GIS environmental. In this applied form, basic probability assignment and combined basic probability assignment are applied to measuring map pattem and map pattem combination, respectively; and the environment composed of the only two singleton sets (deposit set and non-deposit set), is used for expressing the entire map area. For a subarea in which the certain map pattern combination exists, the combined basic probability assignment corresponding to the map pattern combination existing in this subarea, expresses the belief of inferring the subarea belonging to the deposit set from the evidence that the corresponding map pattern combination existing in the subarea. Thus, it may be served as a statistical index measuring the relative mineral resource potentials of the subarea. And it may be determined like 1) dividing the map area into a series of small equal-sized grid cells and then select the training sample set composed of the well-known grid cells or the entire grid cells; 2) estimating the basic probability assignments corresponding to each map pattern fromthe training sample set; 3) determining the map pattern combination existing in each cell, and then appling the Dempster's Rule of Combination to integrating the all basic probability assignments corresponding to the map patterns existing in the cell into the combined basic probability assignment. Mineral resource potential mapping with the Dempster-Shafer theory is demonstrated on a case study to select mineral resource targets. The experimental results manifest that the model can be compared with the weights of evidence model in the effectiveness of mineral resource target selection. 展开更多
关键词 ENVIRONMENT Dempster-Shafer theory basic probability assignment combined basic probability assignment mineral resource mineral target selection
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激光照排机驱动程序设计
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作者 苏光奎 朱欣焰 张银洲 《武汉测绘科技大学学报》 CSCD 1998年第1期81-84,共4页
在介绍激光照排机工作原理、激光照排机控制接口电路的基础上,详细介绍了磁盘中的图形文件数据的读取方法、图形文件的表示形式及位图文件的分段存取和输出方法。既解决了输出数据量大与存贮空间小的矛盾,又解决了输出速度快与磁盘存... 在介绍激光照排机工作原理、激光照排机控制接口电路的基础上,详细介绍了磁盘中的图形文件数据的读取方法、图形文件的表示形式及位图文件的分段存取和输出方法。既解决了输出数据量大与存贮空间小的矛盾,又解决了输出速度快与磁盘存取速度慢的矛盾,实现了整幅位图数据文件连续读取、分段传送、多级缓冲、激光照排机连续输出多幅图形的功能。 展开更多
关键词 激光照排机 输出控制 位图数据 驱动 程序设计
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Suitability mapping of global wetland areas and validation with remotely sensed data 被引量:7
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作者 ZHU Peng GONG Peng 《Science China Earth Sciences》 SCIE EI CAS 2014年第10期2283-2292,共10页
With increasing urbanization and agricultural expansion, large tracts of wetlands have been either disturbed or converted to other uses. To protect wetlands, accurate distribution maps are needed. However, because of ... With increasing urbanization and agricultural expansion, large tracts of wetlands have been either disturbed or converted to other uses. To protect wetlands, accurate distribution maps are needed. However, because of the dramatic diversity of wetlands and difficulties in field work, wetland mapping on a large spatial scale is very difficult to do. Until recently there were only a few high resolution global wetland distribution datasets developed for wetland protection and restoration. In this paper, we used hydrologic and climatic variables in combination with Compound Topographic Index (CTI) data in modeling the average annual water table depth at 30 arc-second grids over the continental areas of the world except for Antarctica. The water table depth data were modeled without considering influences of anthropogenic activities. We adopted a relationship between poten- tial wetland distribution and water table depth to develop the global wetland suitability distribution dataset. The modeling re- suits showed that the total area of global wetland reached 3.316× 10^7 km^2. Remote-sensing-based validation based on a compi- lation of wetland areas from multiple sources indicates that the overall accuracy of our product is 83.7%. This result can be used as the basis for mapping the actual global wetland distribution. Because the modeling process did not account for the im- pact of anthropogenic water management such as irrigation and reservoir construction over suitable wetland areas, our result represents the upper bound of wetland areas when compared with some other global wetland datasets. Our method requires relatively fewer datasets and has a higher accuracy than a recently developed global wetland dataset. 展开更多
关键词 global wetland suitability distribution water balance model CTI accuracy assessment
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A locality-based replication manager for data cloud
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作者 Reza SOOKHTSARAEI Javad ARTIN +2 位作者 Ali GHORBANI Ahmad FARAAHI Hadi ADINEH 《Frontiers of Information Technology & Electronic Engineering》 SCIE EI CSCD 2016年第12期1275-1286,共12页
Efficient data management is a key issue for environments distributed on a large scale such as the data cloud. This can be taken into account by replicating the data. The replication of data reduces the time of servic... Efficient data management is a key issue for environments distributed on a large scale such as the data cloud. This can be taken into account by replicating the data. The replication of data reduces the time of service and the delay in availability, increases the availability, and optimizes the distribution of load in the system. It is worth mentioning, however, that with the replication of data, the use of resources and energy increases due to the storing of copies of the data. We suggest a replication manager that decreases the cost of using resources, energy, and the delay in the system, and also increases the availability of the system. To reach this aim, the suggested replication manager, called the locality replication manager (LRM), works by using two important algorithms that use the physical adjacency feature of blocks. In addition, a set of simulations are reported to show that LRM can be a suitable option for distributed systems as it uses less energy and resources, optimizes the distribution of load, and has more availability and less delay. 展开更多
关键词 Data cloud REPLICATION GRAPH Locality replication manager (LRM)
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Positioning of the CE-1's impact site based on CCD image data photographed during the controlled impact on the Moon
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作者 LIU JianJun REN Xin +3 位作者 ZOU XiaoDuan WANG WenRui MOU LingLi LI ChunLai 《Science China Earth Sciences》 SCIE EI CAS 2012年第1期83-89,共7页
Up to now, many lunar explorations concluded their scientific mission through the impact on the lunar surface. The prediction and positioning of impact sites are based on the extrapolated orbiting data together with t... Up to now, many lunar explorations concluded their scientific mission through the impact on the lunar surface. The prediction and positioning of impact sites are based on the extrapolated orbiting data together with the real time orbiting data and observations from ground based telescope provided by TT & C System. As most lunar missions carded cameras onboard, a new method of positioning of CE-1 impact site is put forward. It is based on the CCD image data photographed during the con- trolled impact and the existing lunar terrain data. Test results from this new method also validate the published impact site po sition. 展开更多
关键词 Chang'E-1 lunar impact POSITIONING
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