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从用“图”带题走向构“图”得形——里程表问题的教学实践与思考
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作者 陈新福 陈艳 《教学月刊(小学版)(数学)》 2016年第10期34-36,共3页
用几何直观或者说用直观图来进行教学是一线教师常用的教学策略,就三年级上册“加与减”单元中的“里程问题”这块内容教学而言,可以从用“图”带题、看题想“图”、构“图”得形三个角度入手,从而为教学中如何运用好几何直观这一教学... 用几何直观或者说用直观图来进行教学是一线教师常用的教学策略,就三年级上册“加与减”单元中的“里程问题”这块内容教学而言,可以从用“图”带题、看题想“图”、构“图”得形三个角度入手,从而为教学中如何运用好几何直观这一教学策略提供参考。 展开更多
关键词 用“图” “图 “图
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A Cognitive Study on Politeness Intention Processing and Its Association with Pragmatic Failure in Cross-Cultural Communication
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作者 Rong YAN Tengfei FENG Samad ZARE 《Chinese Journal of Applied Linguistics》 2024年第3期481-497,525,共18页
Although a large number of studies have focused on various aspects of politeness,very little is known about how politeness intention is activated cognitively during verbal communication.The present study aims to explo... Although a large number of studies have focused on various aspects of politeness,very little is known about how politeness intention is activated cognitively during verbal communication.The present study aims to explore the cognitive mechanism of politeness intention processing,and how it is related to pragmatic failure during cross-cultural communication.Using 30 Chinese EFL university students who were instructed to finish a probe word judgment task with 96 virtual scenarios,the results indicate that within both mono-and cross-cultural contexts,the response time in the experimental scenarios was significantly slower than that of the filler scenarios.This suggests that politeness intention was activated while understanding the surface meaning of the conversation;however,the EFL learners could not completely avoid the negative transfer of their native politeness conventions when they were comprehending the conversational intention of the target language.Furthermore,no significant differences in response time were found between the groups with high and low English pragmatic competence,illustrating that transferring the pragmatic rules and principles into cross-cultural communication skills was more cognitively demanding.Overall,this study adds to the literature on politeness research and provides some implications for foreign language pragmatic instructions. 展开更多
关键词 politeness intention cognitive processing pragmatic failure cross-cultural pragmatics cross-cultural communication
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基于无线传感器网络定位技术的图书馆智能管理创新 被引量:3
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作者 罗桦 陈勇 +2 位作者 张清 赵滟 黄猛 《大学图书情报学刊》 2016年第2期50-52,57,共4页
"互联网+"时代,信息技术的发展对图书馆的智能化管理工作提出了更高的要求。文章概述了无线传感器网络与定位技术,重点讨论了如何将WSN定位技术运用到图书智能管理,通过定位技术与大数据、云计算等信息技术的结合,推动图书馆... "互联网+"时代,信息技术的发展对图书馆的智能化管理工作提出了更高的要求。文章概述了无线传感器网络与定位技术,重点讨论了如何将WSN定位技术运用到图书智能管理,通过定位技术与大数据、云计算等信息技术的结合,推动图书馆智能系统建设和智能化发展。 展开更多
关键词 书馆 智能管理 无线传感器网络 定位技术 互联网+
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Application of the equivalent offset migration method in acoustic log reflection imaging 被引量:6
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作者 张铁轩 陶果 +2 位作者 李君君 王兵 王华 《Applied Geophysics》 SCIE CSCD 2009年第4期303-310,393,共9页
Borehole acoustic reflection logging can provide high resolution images of nearborehole geological structure. However, the conventional seismic migration and imaging methods are not effective because the reflected wav... Borehole acoustic reflection logging can provide high resolution images of nearborehole geological structure. However, the conventional seismic migration and imaging methods are not effective because the reflected waves are interfered with the dominant borehole-guided modes and there are only eight receiving channels per shot available for stacking. In this paper, we apply an equivalent offset migration method based on wave scattering theory to process the acoustic reflection imaging log data from both numerical modeling and recorded field data. The result shows that, compared with the routine post-stack depth migration method, the equivalent offset migration method results in higher stack fold and is more effective for near-borehole structural imaging with low SNR acoustic reflection log data. 展开更多
关键词 acoustic reflection logging common scatter point gather signal processing nearborehole structure imaging
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Online composite shape recognition based on relevance feedback
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作者 王强 孙正兴 《Journal of Southeast University(English Edition)》 EI CAS 2005年第2期153-158,共6页
This paper describes a novel method of online composite shape recognition interms of the relevance feedback technology to capture a user's intentions incrementally, and adynamic user modeling method to adapt to va... This paper describes a novel method of online composite shape recognition interms of the relevance feedback technology to capture a user's intentions incrementally, and adynamic user modeling method to adapt to various users' styles. First, the relevance feedback isadapted to refine the recognition results and reduce the ambiguity incrementally based on theestablishment of a feature-based vector model of a user's sketches. Secondly, a dynamic usermodeling is introduced to model the user's sketching habits based on recording and analyzinghistorical information incrementally. A model-based matching strategy is also employed in the methodto recognize sketches dynamically. Experiments prove that the proposed method is both effective andefficient. 展开更多
关键词 sketchy-based user interface online composite shape recognition dynamicuser modeling relevance feedback
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Projection registration of X-ray image and CT image
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作者 张惠 罗立民 +2 位作者 舒华忠 李松毅 Pascal Haigron 《Journal of Southeast University(English Edition)》 EI CAS 2003年第1期26-30,共5页
A methodology for alignment of an X-ray image and a CT image, based on the Chamfer 3-4 distance transform and simulated annealing optimization algorithm is presented. Firstly, an initial transformation matrix is const... A methodology for alignment of an X-ray image and a CT image, based on the Chamfer 3-4 distance transform and simulated annealing optimization algorithm is presented. Firstly, an initial transformation matrix is constructed. For the convenience of computing, geometric models of the X-ray device to reconstruct the calibration matrix are used. Then, by defining the distance between the 3-D protective and the 2-D object image, we optimize this distance matching problem, using the simulated annealing algorithm. This method is also integrated into medical intra-operation, dealing with the data set acquired from 3-D image workstation and active navigation. 展开更多
关键词 image registration calibration matrix image segmentation distance transformation simulated annealing
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Geo-information Tupu Analysis of Land Use Change in Haihe River Basin 被引量:2
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作者 朱占永 郭伟志 张海力 《Agricultural Science & Technology》 CAS 2012年第5期1139-1144,共6页
[Objective] This study was to provide basis for the scientific management of land use in Haihe River Basin (HRB) through the quantitative exploration of the land use conversion, changes of intensity and spatial dist... [Objective] This study was to provide basis for the scientific management of land use in Haihe River Basin (HRB) through the quantitative exploration of the land use conversion, changes of intensity and spatial distribution in this region. [Method] With the support of remote sensing technology and geographic information technology, the land use maps of the study area in 40 years (1970-2010) were in- terpreted and plotted. Four kinds of tupu, namely, land use change tupu, process tupu, arising tupu and evolution mode tupu were built through the spatial overlay of the land use maps to analyze the change rules of land use patterns. [Result] The conversion of arable land to construction land was the main characteristics of land use changes in HRB for the 40 years; the area of non-stable region accounted for 35% of the total, indicating that the land use changed remarkably, thus, it was nec- essary to strengthen the scientific land management in HRB; the new conversions to all land use patterns were all the lowest in 1980-1990, indicating that land use changed slowly during this period. [Conclusion] The results indicate that, compared with conventional transfer matrix method, geo-information tupu has obvious advantage in analyzing land use changes that it can demonstrate the spatial distribution of interest region, display the multi-dimensional spatial information. 展开更多
关键词 Haihe river basin Tupu analysis Land use change Evolution mode
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Method for test case selection and execution of web application regression testing
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作者 曹曦 许蕾 《Journal of Southeast University(English Edition)》 EI CAS 2008年第3期325-329,共5页
In order to improve the efficiency of regression testing in web application,the control flow graph and the greedy algorithm are adopted.This paper considers a web page as a basic unit and introduces a test case select... In order to improve the efficiency of regression testing in web application,the control flow graph and the greedy algorithm are adopted.This paper considers a web page as a basic unit and introduces a test case selection method for web application regression testing based on the control flow graph.This method is safe enough to the test case selection.On the base of features of request sequence in web application,the minimization technique and the priority of test cases are taken into consideration in the process of execution of test cases in regression testing for web application.The improved greedy algorithm is also raised resulting in optimization of execution of test cases.The experiments indicate that the number of test cases which need to be retested is reduced,and the efficiency of execution of test cases is also improved. 展开更多
关键词 regression testing web application test case selection control flow graph optimizing execution
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Parallel hydrodynamic finite element model with an N-Best refining partition scheme 被引量:2
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作者 张振昌 洪华生 +2 位作者 WAI Onyx Winghong 江毓武 周昌乐 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2010年第6期1340-1349,共10页
We enhance a robust parallel finite element model for coasts and estuaries cases with the use of N-Best refinement algorithms,in multilevel partitioning scheme.Graph partitioning is an important step to construct the ... We enhance a robust parallel finite element model for coasts and estuaries cases with the use of N-Best refinement algorithms,in multilevel partitioning scheme.Graph partitioning is an important step to construct the parallel model,in which computation speed is a big concern.The partitioning strategy includes the division of the research domain into several semi-equal-sized sub-domains,minimizing the sum weight of edges between different sub-domains.Multilevel schemes for graph partitioning are divided into three phases:coarsening,partitioning,and uncoarsening.In the uncoarsening phase,many refinement algorithms have been proposed previously,such as KL,Greedy,and Boundary refinements.In this study,we propose an N-Best refinement algorithm and show its advantages in our case study of Xiamen Bay.Compared with original partitioning algorithm in previous models,the N-Best algorithm can speed up the computation by 1.9 times,and the simulation results are in a good match with the in-situ data. 展开更多
关键词 N-Best graph partitioning parallel computation finite element method (FEM) DOMAINDECOMPOSITION
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Quantitative research of diagenesis:its effect on pore evolution of the Fuyu oil reservoir in the north Qijia region 被引量:4
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作者 HAO Guoli SHAN Xuanlong +1 位作者 LIU Wanzhu WANG Qingbin 《Mining Science and Technology》 EI CAS 2010年第5期770-777,共8页
From observing cores of 18 wells,identifying 175 ordinary thin sections and 61 thin casting sections,energy spectrum analyses of 37 samples,homogenization temperature measurement of fluid inclusions of 11 samples,we d... From observing cores of 18 wells,identifying 175 ordinary thin sections and 61 thin casting sections,energy spectrum analyses of 37 samples,homogenization temperature measurement of fluid inclusions of 11 samples,we determine the types of diagenesis and pores of the Fuyu oil reservoir in the north Qijia region.We classified the pores and measured their plane porosity using CIA 2000,the software of rock image analysis,calculated the effect of different kinds of diagenesis on porosity,studied the controlling actions of diagenesis to pore evolution quantitatively,combined with burial history,thermal history and their diagenetic environments.Our results show that mechanical compaction and carbonate cementation are the major destructive diagenesed,developed during early diagenesis stages.The reduction in porosity by mechanical compaction and carbonate cementation are about 25% and 8%,while the destructive intensity of siliceous cementation and clay mineral cementation is relatively much smaller,i.e.,the reduction of porosity is about 2% and 0.2% Dissolution is constructive diagenesis,the increment of porosity is about 6%.There are four diagenesis evolution stages,during which the porosity reduced from 30%~38% to 2%~20%.Mechanical compaction and early cementation are the main diageneses in the early diagenesis stages,when porosity was reduced to 2%~10%.Dissolution is the main diagenesis of an A I substage of the middle diagenesis stage,when porosity increased 1%~8%.The dissolution of the A Ⅱ substage of the middle diagenesis stage affected by late cementation,raised porosity 1%~5%.The porosity varied slightly during the middle stage B. 展开更多
关键词 north Qijia region Fuyu oil reservoir DIAGENESIS pore evolution quantitative research
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Water quality forecast through application of BP neural network at Yuqiao reservoir 被引量:21
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作者 ZHAO Ying NAN Jun +1 位作者 CUI Fu-yi GUO Liang 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2007年第9期1482-1487,共6页
This paper deals with the study of a water quality forecast model through application of BP neural network technique and GUI (Graphical User Interfaces) function of MATLAB at Yuqiao reservoir in Tianjin. To overcome t... This paper deals with the study of a water quality forecast model through application of BP neural network technique and GUI (Graphical User Interfaces) function of MATLAB at Yuqiao reservoir in Tianjin. To overcome the shortcomings of traditional BP algorithm as being slow to converge and easy to reach extreme minimum value,the model adopts LM (Leven-berg-Marquardt) algorithm to achieve a higher speed and a lower error rate. When factors affecting the study object are identified,the reservoir's 2005 measured values are used as sample data to test the model. The number of neurons and the type of transfer functions in the hidden layer of the neural network are changed from time to time to achieve the best forecast results. Through simulation testing the model shows high efficiency in forecasting the water quality of the reservoir. 展开更多
关键词 Water quality forecast BP neural network MATLAB Graphical User Interfaces (GUI)
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The non-point output of different agriculture landuse types in Zhexi hydraulic region of Taihu Basin 被引量:2
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作者 LIHengpeng LIUXiaomei HUANGWenyu 《Journal of Geographical Sciences》 SCIE CSCD 2004年第2期151-158,共8页
This paper takes Zhexi hydraulic region in Taihu Basin as a study area. On the basis of hydraulic analysis function of Arcgis8.3, the drainages were delineated by selecting the monitoring points and discharge stations... This paper takes Zhexi hydraulic region in Taihu Basin as a study area. On the basis of hydraulic analysis function of Arcgis8.3, the drainages were delineated by selecting the monitoring points and discharge stations as outlets. The landuse map were finished by denoting the TM/ETM image. The precipitation map was finished by spatial interpolation according to the rainfall monitoring records. Overlaying the drainage boundary, landuse map and precipitation map, the rainfall, different landuse type area, and runoff pollution concentration and runoff were calculated. Based on these data in different sub-watersheds, by Origin7.0 regression tool, an equation is established to predict runoff using the relationships between runoff, precipitation depth and land use patterns in each of the sub-watersheds. Selecting the sub-watershed which is mainly composed of forest landuse type, the mean runoff concentration (MRC) from sub-watershed has been estimated. The mean runoff concentration of farmland has been estimated by the same methods after the contribution of forest landuse type was removed. The results are: for the forest landuse type, the mean runoff concentrations of COD, BOD, Total N and Total P are 2.95 mg/l, 1.080 mg/l, 0.715 mg/l, and 0.039 mg/l, respectively; for the farmland, the mean runoff concentrations of COD, BOD, Total N and Total P are 5.721 mg/l, 3.097 mg/l, 2.092 mg/l, and 0.166 mg/l, respectively. By using these results, the agriculture non-point pollution loads have been assessed. The loads of COD, BOD, Total N and Total P in Zhexi region are 14,631.69 t/a, 6401.93 t/a, 4281.753 t/a and 287.67 t/a, respectively. 展开更多
关键词 Taihu Basin Zhexi hydraulic region LANDUSE non-point pollution
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On the application of DInSAR to deformation monitoring in desert areas 被引量:1
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作者 Chang Xiao-Tao Guo Jin-Yun +1 位作者 Zhang Yong-Hong Wang Xiao-Qing 《Applied Geophysics》 SCIE CSCD 2011年第1期86-93,96,共9页
The DInSAR technique is used for monitoring the desert height changes to study sandstorms. Hunshandake Sandy Land, as the test area, is one of the main sources of sandstorms in Beijing. In order to study the sandstorm... The DInSAR technique is used for monitoring the desert height changes to study sandstorms. Hunshandake Sandy Land, as the test area, is one of the main sources of sandstorms in Beijing. In order to study the sandstorm source and its impact, a pair of EnviSat ASAR images of Oct. 11, 2005, and Oct. 26, 2004, is processed on the basis of analysis of six ERS-2 and EnviSat radar images. After the image configuration, flat earth effect correction, data filtering, phase unwrapping, and geo-coding, a deformation model over Hunshandake desert is built. According to the results, the height decreased in most areas and increased in a few areas, which basically coincides with the strong sandstorm appearing in Beijing in the Spring of 2005. The results show DInSAR has an important role in monitoring of desert surface deformation. 展开更多
关键词 DINSAR Hunshandake Sandy Land height change monitoring SANDSTORM
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An Adaptable Walking-skid for Seabed ROV under Strong Current Disturbance 被引量:5
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作者 Jianting Si Chengsiong Chin 《Journal of Marine Science and Application》 2014年第3期305-314,共10页
This paper proposed a new concept of an adaptable multi-legged skid design for retro-fitting to a remotely-operated vehicle (ROV) during high tidal current underwater pipeline inspection. The sole reliance on propel... This paper proposed a new concept of an adaptable multi-legged skid design for retro-fitting to a remotely-operated vehicle (ROV) during high tidal current underwater pipeline inspection. The sole reliance on propeller-driven propulsion for ROV is replaced with a proposed low cost biomimetic solution in the form of an attachable hexapod walking skid. The advantage of this adaptable walking skid is the high stability in positioning and endurances to strong current on the seabed environment. The computer simulation flow studies using Solidworks Flow Simulation shown that the skid attachment in different compensation postures caused at least four times increase in overall drag, and negative lift forces on the seabed ROV to achieve a better maneuvering and station keeping under the high current condition (from 0.5 m/s to 5.0 m/s). A graphical user interface is designed to interact with the user during robot-in-the-loop testing and kinematics simulation in the pool. 展开更多
关键词 ROV HEXAPOD multi-legged SKID SEABED tidal current
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Estimation of coal particle size distribution by image segmentation 被引量:10
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作者 Zhang Zelin Yang Jianguo Ding Lihua Zhao Yuemin 《International Journal of Mining Science and Technology》 SCIE EI 2012年第5期739-744,共6页
Several industrial coal processes are largely determined by the distribution of particle sizes in their feed.Currently these parameters are measured by manual sampling,which is time consuming and cannot provide real t... Several industrial coal processes are largely determined by the distribution of particle sizes in their feed.Currently these parameters are measured by manual sampling,which is time consuming and cannot provide real time feedback for automatic control purposes.In this paper,an approach using image segmentation on images of overlapped coal particles is described.The estimation of the particle size distribution by number is also described.The particle overlap problem was solved using image enhancement algorithms that converted those image parts representing material in lower layers to black.Exponential high-pass filter(EHPF) algorithms were used to remove the texture from particles on the surface.Finally,the edges of the surface particles were identified by morphological edge detection.These algorithms are described in detail as is the method of extracting the coal particle size.Tests indicate that using more coal images gives a higher accuracy estimate.The positive absolute error of 50 random tests was consistently less than 2.5% and the errors were reduced as the size of the fraction increased. 展开更多
关键词 Coal size distribution Overlap problem Estimation Feature extraction
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Urban Land Use Change Detection Using Multisensor Satellite Images 被引量:5
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作者 DENG Jin-Song WANG Ke +1 位作者 LI Jun DENG Yan-Hua 《Pedosphere》 SCIE CAS CSCD 2009年第1期96-103,共8页
Due to inappropriate planning and management, accelerated urban growth and tremendous loss in land, especially cropland, have become a great challenge for sustainable urban development in China, especially in develope... Due to inappropriate planning and management, accelerated urban growth and tremendous loss in land, especially cropland, have become a great challenge for sustainable urban development in China, especially in developed urban area in the coastal regions; therefore, there is an urgent need to effectively detect and monitor the land use changes and provide accurate and timely information for planning and management. In this study a method combining principal component analysis (PCA) of multisensor satellite images from SPOT (systeme pour l'observation de la terre or earth observation satellite)-5 multispectral (XS) and Landsat-7 enhanced thematic mapper (ETM) panchromatic (PAN) data, and supervised classification was used to detect and analyze the dynamics of land use changes in the city proper of Hangzhou. The overall accuracy of the land use change detection was 90.67% and Kappa index was 0.89. The results indicated that there was a considerable land use change (10.03% of the total area) in the study area from 2001 to 2003, with three major types of land use conversions: from cropland into built-up land, construction site, and water area (fish pond). Changes from orchard land into built-up land were also detected. The method described in this study is feasible and useful for detecting rapid land use change in the urban area. 展开更多
关键词 change detection land use multisensor satellite image principal component analysis (PCA) urban area
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Performance of dual-source CT with high pitch spiral mode for coronary stent patency compared with invasive coronary angiography 被引量:10
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作者 Xia YANG Qiang YU +4 位作者 Wei DONG Zhen-Hong FU Jun-Jue YANG Jun GUO Yun-Dai CHEN 《Journal of Geriatric Cardiology》 SCIE CAS CSCD 2016年第10期817-823,共7页
Objective To investigate the performance of dual-source computed tomography (DSCT) using high-pitch spiral fliPS) mode for coronary stents patency. Methods We conducted a prospective study on 120 patients with 260 ... Objective To investigate the performance of dual-source computed tomography (DSCT) using high-pitch spiral fliPS) mode for coronary stents patency. Methods We conducted a prospective study on 120 patients with 260 previous stents implanted due to recurred suspicious symptoms of angina scheduled for invasive coronary angiography (ICA), while DSCT were conducted using HPS mode. Results There was no significant impact of age, body mass index or heat rate (HR) on image quality (P 〉 0.05), while HR variability had a slight impact on that (P 〈 0.05). Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) of DSCT in detection of in-stent restenosis (ISR) based per-patient were 92.3%, 96.7%, 88.9%, and 97.8%, respectively. And those based per-stent were 87%, 96.8%, 83.3%, and 97.7% with un-assessment stents, 97.4%, 99.5%, 97.4%, and 99.5% without un-assessment stents. There was significant differ- ence on sensitivity, specificity, PPV and NPV between diameter 〉 3.0 mm group (93.3%, 97.9%, 87.5%, and 98.9%) and diameter 〈 3.0 mm group (80%, 93.3%, 80.0%, and 93.3%) (P 〈 0.05), and that between stent number 〉 3 group (82.3%, 77.8%, 66.7%, and 60%) with 〈 3 group (97.3%, 80%, 96.5%, and 75%). The effective dose of DSCT (1.4 ± 0.5 mSv) is significantly less than that by invasive coronary angiography [4.0 ± 0.8 mSv (P 〈 0.01)]. Conclusion DSCT using HPS mode provides good diagnostic performance on stent patency with lower effective dose in patients with HR 〈 65 beats/rain. 展开更多
关键词 Coronary angiography High-pitch spiral mode Percutaneous coronary intervention STENT
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A New Fusion Technique of Remote Sensing Images for Land Use/Cover 被引量:24
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作者 WULian-Xi SUNBo +2 位作者 ZHOUSheng-Lu HUANGShu-E ZHAOQi-Guo 《Pedosphere》 SCIE CAS CSCD 2004年第2期187-194,共8页
In China, accelerating industrialization and urbanization followinghigh-speed economic development and population increases have greatly impacted land use/coverchanges, making it imperative to obtain accurate and up t... In China, accelerating industrialization and urbanization followinghigh-speed economic development and population increases have greatly impacted land use/coverchanges, making it imperative to obtain accurate and up to date iufbimation on changes soas toevaluate their environmental effects. The major purpose of this study was to develop a new method tofuse lower spatial resolution multispectral satellite images with higher spatial resolutionpanchromatic ones to assist in land use/cover mapping.An algorithm of a new fusion method known asedge enhancement intensity modulation (EEIM) was proposed to merge two optical image data sets ofdifferent spectral ranges. The results showed that the EEIM image was quite similar in color tolower resolution multispectral images, and the fused product was better able to preserve spectralinformation. Thus, compared to conventional approaches, the spectral distortion of the fused imageswas markedly reduced. Therefore, the EEIM fusion method could be utilized to fuse remote sensingdata from the same or different sensors, including TM images and SPOT5 panchromatic images,providing high quality land use/cover images. 展开更多
关键词 EEIM FUSION land cover land use remote sensing spectral preservation
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Shear-Flow Induced Secondary Circulation in Parallel Underwater Topographic Corrugation and Its Application to Satellite Image Interpretation 被引量:2
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作者 ZHENG Quanan ZHAO Qing +5 位作者 YUAN Yeli LIU Xian HU Jianyu LIU Xuehai YIN Liping YE Xiaomin 《Journal of Ocean University of China》 SCIE CAS 2012年第4期427-435,共9页
This study aims to figure out satellite imaging mechanisms for submerged sand ridges in the shallow water region in the case of the flow parallel to the topography corrugation.Solving the disturbance governing equatio... This study aims to figure out satellite imaging mechanisms for submerged sand ridges in the shallow water region in the case of the flow parallel to the topography corrugation.Solving the disturbance governing equations of the shear-flow yields the analytical solutions of the secondary circulation.The solutions indicate that a flow with a parabolic horizontal velocity shear and a sinusoidal vertical velocity shear will induce a pair of vortexes with opposite signs distributed symmetrically on the two sides of central line of a rectangular canal.In the case of the presence of surface Ekman layer with the direction of Ekman current opposite to(coincident with) the mean flow,the two vortexes converge(diverge) at the central line of canal in the upper layer and form a surface current convergent(divergent) zone along the central line of the canal.In the case of the absence of surface Ekman layer,there is no convergent(divergent) zone formed over the sea surface.The theoretical results are applied to interpretations of three convergent cases,one divergent case and statistics of 27 cases of satellite observations in the submerged sand ridge region of the Liaodong Shoal in the Bohai Sea.We found that the long,finger-like,bright patterns on SAR images are corresponding to the locations of the canals(or tidal channels) formed by two adjacent sand ridges rather than the sand ridges themselves. 展开更多
关键词 secondary circulation Bohai Sea submerged sand ridges satellite images
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Bacterial graphical user interface oriented by particle swarm optimization strategy for optimization of multiple type DFACTS for power quality enhancement in distribution system 被引量:3
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作者 M.Mohammadi M.Montazeri S.Abasi 《Journal of Central South University》 SCIE EI CAS CSCD 2017年第3期569-588,共20页
This study proposes a graphical user interface(GUI) based on an enhanced bacterial foraging optimization(EBFO) to find the optimal locations and sizing parameters of multi-type DFACTS in large-scale distribution syste... This study proposes a graphical user interface(GUI) based on an enhanced bacterial foraging optimization(EBFO) to find the optimal locations and sizing parameters of multi-type DFACTS in large-scale distribution systems.The proposed GUI based toolbox,allows the user to choose between single and multiple DFACTS allocations,followed by the type and number of them to be allocated.The EBFO is then applied to obtain optimal locations and ratings of the single and multiple DFACTS.This is found to be faster and provides more accurate results compared to the usual PSO and BFO.Results obtained with MATLAB/Simulink simulations are compared with PSO,BFO and enhanced BFO.It reveals that enhanced BFO shows quick convergence to reach the desired solution there by yielding superior solution quality.Simulation results concluded that the EBFO based multiple DFACTS allocation using DSSSC,APC and DSTATCOM is preferable to reduce power losses,improve load balancing and enhance voltage deviation index to 70%,38% and 132% respectively and also it can improve loading factor without additional power loss. 展开更多
关键词 distribution system power quality single type and multiple type DFACTS BFO algorithm particle swarm optimization(PSO)
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