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“云图”,一个不可忽视的环节
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作者 钱莉莉 王强强 《浙江教学研究》 2005年第1期5-6,共2页
“云图”是新教材特有的一个区别于传统教材的显著特点。本文试图从教材编写者的角度出发,阐述“云图”在教育教学中的作用.揭开其中蕴涵的厚重而深刻的教学原理,旨在激发广大师生充分重视“云图”的存在,领会编者的良苦用心,充分... “云图”是新教材特有的一个区别于传统教材的显著特点。本文试图从教材编写者的角度出发,阐述“云图”在教育教学中的作用.揭开其中蕴涵的厚重而深刻的教学原理,旨在激发广大师生充分重视“云图”的存在,领会编者的良苦用心,充分发挥“云图”应有的教育教学功能。 展开更多
关键词 “云图” 课程改革 教学功能 心理学 认知结构 问题情境 教学内容 初中 数学教学
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关于推进数值地震预测的思考 被引量:3
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作者 黄辅琼 张晓东 +2 位作者 曹则贤 李建平 李世海 《国际地震动态》 2017年第4期4-10,共7页
在广泛查阅国际地震预报研究动态的基础上,根据当前数值地震预测研究中面临的问题和相关问题的研究进展,对未来推动数值地震预测研究的有关方面进行了初步讨论,以达抛砖引玉之效。借鉴数值天气预报的发展历程,发展数值地震预报首先亟需... 在广泛查阅国际地震预报研究动态的基础上,根据当前数值地震预测研究中面临的问题和相关问题的研究进展,对未来推动数值地震预测研究的有关方面进行了初步讨论,以达抛砖引玉之效。借鉴数值天气预报的发展历程,发展数值地震预报首先亟需就各种观测资料进行四维"同化"分析,形成地震孕育过程中线性能量积累阶段、非线性转变到亚失稳阶段不同状态连续变化的"模式"地震资料构成的地下四维"云图"。不同途径观测资料的"同化"和亚失稳阶段的数学表达是数值地震预报技术的关键。 展开更多
关键词 数值地震预测 观测资料“同化” “模式”地震 亚失稳状态 地下四维“云图”
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RESEARCH ON SATELLITE IMAGE PROCESSING AND RECOGNITION WITH PARALLEL ALGORITHM 被引量:1
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作者 刘正光 郭爱民 +1 位作者 程彦 刘勇 《Transactions of Tianjin University》 EI CAS 1999年第2期73-77,共5页
Using the method of mathematical morphology,this paper fulfills filtration,segmentation and extraction of morphological features of the satellite cloud image.It also gives out the relative algorithms,which is realized... Using the method of mathematical morphology,this paper fulfills filtration,segmentation and extraction of morphological features of the satellite cloud image.It also gives out the relative algorithms,which is realized by parallel C programming based on Transputer networks.It has been successfully used to process the typhoon and the low tornado cloud image.And it will be used in weather forecast. 展开更多
关键词 satellite cloud image extraction of morphological features mathematical morphology parallel processing
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High Performance of Imaging Extraction for Infrared Satellite Cloud Image
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作者 刘正光 刘勇 沈桂雄 《Transactions of Tianjin University》 EI CAS 2002年第4期261-264,共4页
The isotherm is an important feature of infrared satellite cloud images (ISCI), which can directly reveal substantial information of cloud systems. The isotherm extraction of ISCI can remove the redundant information ... The isotherm is an important feature of infrared satellite cloud images (ISCI), which can directly reveal substantial information of cloud systems. The isotherm extraction of ISCI can remove the redundant information and therefore helps to compress the information of ISCI. In this paper, an isotherm extraction method is presented. The main aggregate of clouds can be segmented based on mathematical morphology. T algorithm and IP algorithm are then applied to extract the isotherms from the main aggregate of clouds. A concrete example for the extraction of isotherm based on IBM SP2 is described. The result shows that this is a high efficient algorithm. It can be used in feature extractions of infrared images for weather forecasts. 展开更多
关键词 infrared satellite cloud images (ISCI) isotherm extraction image compression weather forecast
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An Observational Study of Typhoon Imbudo in 2003 被引量:1
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作者 LI Qingqing FU Gang +2 位作者 GUO Jingtian YANG Yuqiang DUAN Yihong 《Journal of Ocean University of China》 SCIE CAS 2005年第4期391-397,共7页
Typhoon Imbudo was a super-typhoon over the northwestern Pacific in 2003. It caused tremendous damage when it made landfalls in the Philippines and China. This paper documents observational analyses of Typhoon Imbudo ... Typhoon Imbudo was a super-typhoon over the northwestern Pacific in 2003. It caused tremendous damage when it made landfalls in the Philippines and China. This paper documents observational analyses of Typhoon Imbudo during its landfall in China. All available observations are used to study its motion, intensity changes, convection, structure and precipitation. Best-track data indicate that Imbudo moved west-northwestward until 1800 UTC 23 July and then turned northwestward. FNL (final) analysis data show that the motion of Imbudo is dominated by changes of the subtropical high. At Imbudo's mature stage, the minimum sea level pressure dropped to 910 hPa and the maximum sustained winds were as high as 67 m s 1, which is the intensity of a super-typhoon. The surface wind field exhibited asymmetric characteristics. Polar-orbiting satellite imagery also manifested convective asymmetry before Imbudo made landfall in China. Analyzed the vertical wind shear, it is shown that the convection has a downshear-left pattern. All kinds of precipitation data were used to identify the asymmetric characteristic of the rainfall associated with the Imbudo. The maximum rainfalls were located in the southern boundary area between Guangxi and Guangdong. However, the lack of in situ observations limited further analyses of this typhoon. 展开更多
关键词 Typhoon Imbudo surface winds satellite imagery asymmetric convection downshear-left convective pattern asymmetric rainfall
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Local Spiral Curves Simulating Based on Hough Transformation and Center Auto-Locating of Developing Typhoon 被引量:1
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作者 王萍 郭传澍 罗颖昕 《Transactions of Tianjin University》 EI CAS 2006年第2期142-146,共5页
In the developing phase of typhoon formation, the spiral belt partly emerges in satellite cloud images. This research starts from images and moves on to graphics and then to representation and recognition. Following t... In the developing phase of typhoon formation, the spiral belt partly emerges in satellite cloud images. This research starts from images and moves on to graphics and then to representation and recognition. Following this route, local spiral cloud belt is segmented from the raw images using image segmentation, the spiral information is extracted using mathematic morphology, and local spiral curves are detected using Hough transformation. The problem of center locating of developing typhoon has finally been solved through a search algorithm of spiral curve. For No. 99082008 cloud image, the result produced by the algorithm in this paper is at 122..3 degree west longitude, 117.5 degree north latitude. The real typhoon center location was at 122.4 degree west longitude, 18 degree north latitude. 展开更多
关键词 Hough transformation spiral curve simulating infrared satellite cloud images center locating of developing typhoon
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Study on the Design Method of the Jack-up's X-Type Cantilever Allowable Load Nephogram 被引量:1
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作者 Yazhou Zhu Chengmeng Sun +2 位作者 Hongde Qin Bin Jiang Yansong Fan 《Journal of Marine Science and Application》 2014年第3期315-320,共6页
The extending of a cantilever and transverse moving of a drilling floor enable the jack-up to operate in several well positions after the Jack-up has pitched. The cantilever allowable load nephogram is the critical re... The extending of a cantilever and transverse moving of a drilling floor enable the jack-up to operate in several well positions after the Jack-up has pitched. The cantilever allowable load nephogram is the critical reference which can evaluate the jack-up's drilling ability, design the cantilever structure and instruct a jack-up manager to make the operations safe. The intent of this paper is to explore the interrelationships between the cantilever position, drilling floor and the loads including wind force, the stand set-back weight etc., through analyzing the structure and load characteristics of the x-type cantilever and the simplified mechanics model with the restriction of the maximum moment capacity of the cantilever single side beam. Referring to several typical position designs load values, the cantilever allowable load nephogram is obtained by using the suitable interpolation method. The paper gives a method for cantilever allowable load design, which is proved reliable and effective by the calculation example. 展开更多
关键词 JACK-UP cantilever expand cantilever allowable loadnephogram drilling ability x-type cantilever
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Improved Geological Mapping Using Landsat-5 TM Data in Weixi Area, Yunnan Province, China 被引量:1
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作者 Tarik Bashir Benomar 《Geo-Spatial Information Science》 2005年第2期110-114,共5页
Different image processing algorithms have been evaluated in the context of geological mapping using Landsat TM data. False color composites, the principal component imagery, and IHS decorrelation stretching method fo... Different image processing algorithms have been evaluated in the context of geological mapping using Landsat TM data. False color composites, the principal component imagery, and IHS decorrelation stretching method for Landsat-5 TM data have been found useful for delineating the regional geological features, mainly to provide the maximum geological information of the studied area . The study testifies that using which image processing yields best results for geological mapping in arid and semiarid regions by preserving morphological and spectral information. Generally, the studied area can be divided into three main geological units: Basaltic intrusive rocks, Metamorphic with varying intensities and Sedimentary rocks. 展开更多
关键词 false color composites IHS decorrelation principal component
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Study on Causes of a Local Heavy Rainstorm Process in Shandong Province
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作者 纪凡华 韩雪蕾 +1 位作者 徐娟 李楠 《Agricultural Science & Technology》 CAS 2017年第2期325-328,共4页
Based on conventional meteorological observation data, NECP 1°×1° reanalysis data, precipitation data from automatic weather stations on the ground, FY- 2E satellite cloud images, and so forth, the circ... Based on conventional meteorological observation data, NECP 1°×1° reanalysis data, precipitation data from automatic weather stations on the ground, FY- 2E satellite cloud images, and so forth, the circulation background, formation mechanism and features of a satellite cloud image of a local heavy rainstorm process in Shandong Province during August 8-9 in 2010 were analyzed. The results showed that the slow eastward movement of short-wave trough at middle and high latitudes, the stable maintenance of the subtropical high and ground cyclone, and the strong development of extra low-level southeast flow were large-scale circulation back- grounds of occurrence of the rainstorm; the rainstorm generated under the effects of mesoscale echo clusters or echo belts and mesoscale convective cloud clusters; precipitation mainly happened in periods when convective cloud clusters generated, developed and matured, and short-time heavy precipitation mainly appeared in the west, southwest and south of convective cloud clusters; extra low-level southeast flow was very conducive to the occurrence of short-time heavy precipitation; mesoscale convective systems rose in the whole troposphere, and the constant enhancement of low-level θse frontal zone provided favorable unstable energy for the occurrence of convective heavy rainfall. 展开更多
关键词 RAINSTORM Extra low-level southeast flow Mesoscale convective cloud cluster Satellite cloud image
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Revisiting the size of nonspherical particles recorded by optical array probes with a new method based on the convex hull 被引量:1
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作者 Rong Zhang Xu Zhou +5 位作者 Hongyu Li Hanchao Li Lei Wei Yang Gao Qiang Xia Xiangyu Wang 《Atmospheric and Oceanic Science Letters》 CSCD 2022年第3期1-5,共5页
In recent years,the Cloud Imaging Probe(CIP)and Precipitation Imaging Probe(PIP)produced by Droplet Measurement Technologies(DMT)have been introduced by a number of meteorological research and operation centers in Chi... In recent years,the Cloud Imaging Probe(CIP)and Precipitation Imaging Probe(PIP)produced by Droplet Measurement Technologies(DMT)have been introduced by a number of meteorological research and operation centers in China.The supporting software provided by DMT,i.e.,PADS(Particle Analysis and Display System),cannot output detailed information on each individual particle,which definitely limits the in-depth utilization of cloud and precipitation particle image data in China.In this paper,particle-by-particle information was extracted by decompressing the CIP and PIP original particle image data,based on which a new definition of the dimension for nonspherical particles is proposed by using the area of the convex hull enclosing a particle to obtain the equivalent diameter of a circle with equal area.Based on the data detected during one flight in Inner Mongolia,the particle size distribution obtained using the new particle size definition and that used by the other four existing definitions are compared.The results show that the particle number concentration calculated using different particle size definitions can vary by up to an order of magnitude.The result obtained based on the new particle size definition is closest to that calculated with the area-equivalent diameter definition. 展开更多
关键词 Cloud and precipitation particles Particle image Particle size Particle size distribution
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Estimation of Moire Patterns Using Spectral Trajectories in the Complex Plane
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作者 Vladimir SaveUev Sung-Kyu Kim 《Computer Technology and Application》 2012年第5期353-360,共8页
The authors found equations for complex coordinates of spectral peaks and trajectories in the case of two superposed layers, each consisting of two orthogonal gratings. The number of geometric elements in spectra was ... The authors found equations for complex coordinates of spectral peaks and trajectories in the case of two superposed layers, each consisting of two orthogonal gratings. The number of geometric elements in spectra was found for four running parameters and different number of gratings by layers. The shape of trajectories was determined in the corresponding cases. The relationships between parameters were found which could help in reducing the intervals of parameters, in particular the relationship between the inverse aspect ratios. The numerical simulation and the physical experiment were in a good agreement with the theory. The proposed technique seems to be helpful in estimation of occurrence of moir6 patterns in visual displays which makes possible the minimization in the spectral domain without calculation of spectra. 展开更多
关键词 Moire effect moire minimization visual display spectral trajectory.
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Dependent task assignment algorithm based on particle swarm optimization and simulated annealing in ad-hoc mobile cloud 被引量:3
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作者 Huang Bonan Xia Weiwei +4 位作者 Zhang Yueyue Zhang Jing Zou Qian Yan Feng Shen Lianfeng 《Journal of Southeast University(English Edition)》 EI CAS 2018年第4期430-438,共9页
In order to solve the problem of efficiently assigning tasks in an ad-hoc mobile cloud( AMC),a task assignment algorithm based on the heuristic algorithm is proposed. The proposed task assignment algorithm based on pa... In order to solve the problem of efficiently assigning tasks in an ad-hoc mobile cloud( AMC),a task assignment algorithm based on the heuristic algorithm is proposed. The proposed task assignment algorithm based on particle swarm optimization and simulated annealing( PSO-SA) transforms the dependencies between tasks into a directed acyclic graph( DAG) model. The number in each node represents the computation workload of each task and the number on each edge represents the workload produced by the transmission. In order to simulate the environment of task assignment in AMC,mathematical models are developed to describe the dependencies between tasks and the costs of each task are defined. PSO-SA is used to make the decision for task assignment and for minimizing the cost of all devices,which includes the energy consumption and time delay of all devices.PSO-SA also takes the advantage of both particle swarm optimization and simulated annealing by selecting an optimal solution with a certain probability to avoid falling into local optimal solution and to guarantee the convergence speed. The simulation results show that compared with other existing algorithms,the PSO-SA has a smaller cost and the result of PSO-SA can be very close to the optimal solution. 展开更多
关键词 ad-hoc mobile cloud task assignment algorithm directed acyclic graph particle swarm optimization simulated annealing
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公共图书馆公益讲座的实践与思考——以云南省图书馆“云图讲堂”为例
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作者 罗荣 《学园》 2014年第15期185-186,共2页
本文介绍了“云图讲堂”实践的基本情况,通过分析“云图讲堂”现状和存在的问题,为提升“云图讲堂”品质提出了建议。
关键词 公益讲座 “云图讲堂” 公共图书馆讲座联盟
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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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Towards adaptable and tunable cloud-based map-matching strategy for GPS trajectories 被引量:2
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作者 Aftab Ahmed CHANDIO Nikos TZIRITAS +2 位作者 Fan ZHANG Ling YIN Cheng-Zhong XU 《Frontiers of Information Technology & Electronic Engineering》 SCIE EI CSCD 2016年第12期1305-1319,共15页
Smart cities have given a significant impetus to manage traffic and use transport networks in an intelligent way. For the above reason, intelligent transportation systems (ITSs) and location-based services (LBSs) ... Smart cities have given a significant impetus to manage traffic and use transport networks in an intelligent way. For the above reason, intelligent transportation systems (ITSs) and location-based services (LBSs) have become an interesting research area over the last years. Due to the rapid increase of data volume within the transportation domain, cloud environment is of paramount importance for storing, accessing, handling, and processing such huge amounts of data. A large part of data within the transportation domain is produced in the form of Global Positioning System (GPS) data. Such a kind of data is usually infrequent and noisy and achieving the quality of real-time transport applications based on GPS is a difficult task. The map-matching process, which is responsible for the accurate alignment of observed GPS positions onto a road network, plays a pivotal role in many ITS applications. Regarding accuracy, the performance of a map-matching strategy is based on the shortest path between two consecutive observed GPS positions. On the other extreme, processing shortest path queries (SPQs) incurs high computational cost. Current map-matching techniques are approached with a fixed number of parameters, i.e., the number of candidate points (NCP) and error circle radius (ECR), which may lead to uncertainty when identifying road segments and either low-accurate results or a large number of SPQs. Moreover, due to the sampling error, GPS data with a high-sampling period (i.e., less than 10 s) typically contains extraneous datum, which also incurs an extra number of SPQs. Due to the high computation cost incurred by SPQs, current map-matching strategies are not suitable for real-time processing. In this paper, we propose real-time map-matching (called RT-MM), which is a fully adaptive map-matching strategy based on cloud to address the key challenge of SPQs in a map-matching process for real-time GPS trajectories. The evaluation of our approach against state-of-the-art approaches is performed through simulations based on both synthetic and real-word datasets. 展开更多
关键词 Map-matching GPS trajectories Tuning-based Cloud computing Bulk synchronous parallel
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