A learning-based method to detect and segment text from scene images     

JIANG Ren-jie QI Fei-hu XU Li WU Guo-rong ZHU Kai-hua 《浙江大学学报(A卷英文版)》2007,8(4):568-574

This paper proposes a learning-based method for text detection and text segmentation in natural scene images. First, the input image is decomposed into multiple connected-components (CCs) by Niblack clustering algorithm. Then all the CCs including text CCs and non-text CCs are verified on their text features by a 2-stage classification module, where most non-text CCs are discarded by an attentional cascade classifier and remaining CCs are further verified by an SVM. All the accepted CCs are output to result in text only binary image. Experiments with many images in different scenes showed satisfactory performance of our proposed method.  相似文献   

Non-Rigid Medical Image Registration with Joint Histogram Estimation Based on Mutual Information   总被引：1，自引：0，他引：1  

陆雪松  张素  苏和  陈亚珠 《天津大学学报(英文版)》2007,13(6):452-455

A mutual information-based non-rigid medical image registration algorithm is presented. An approximate function of Hanning windowed sinc is used as kernel function of partial volume (PV) interpolation to estimate the joint histogram, which is the key to calculating the mutual information. And a new method is proposed to compute the gradient of mutual information with respect to the model parameters. The transformation of object is modeled by a free-form deformation (FFD) based on B-splines. The experiments on 3D synthetic and real image data show that the algorithm can converge at the global optimum and restrain the emergency of local extreme.  相似文献   

Flow shop rescheduling problem under rush orders   总被引：1，自引：0，他引：1  

胡燕海严隽琪  叶飞帆于军合 《浙江大学学报(A卷英文版)》2005,6(10):1040-1046

INTRODUCTION Rescheduling problem in manufacturing system is considered as a particularly hard combinatorial optimization problem,closely related with uncer-tainty caused by exterior business environment and interior production conditions.Production resched-uling is a common practice in manufacturing compa-nies all over the world.Four sources of production disturbances have been identified:(1)incorrect work;(2)machine breakdowns;(3)rework due to quality problem;and(4)rush orders(Rangsarit…  相似文献   

A four spiral slots microstrip patch antenna for radiotelemetry capsules based on FDTD     

HUANG Biao YAN Guo-zheng LI Qian-ru 《浙江大学学报(A卷英文版)》2007,8(10):1560-1567

Antenna is very crucial to radiotelemetry capsules which can measure the physiological parameters of the gastroin- testinal (GI) tract. The objective of this paper is to design a novel spiral slots microstrip patch antenna for the radiotelemetry capsules communicating with external recorder at 915 MHz located in ISM (Industry, Science, and Medical) bands. The microstrip patch antenna is designed and evaluated using the finite-difference time-domain (FDTD) method. Return loss characteristics and the effect of the human body on resonant frequency are analyzed, and the performances of radiation patterns at different positions of the human alimentary tract are also estimated. Finally, specific absorption rate (SAR) computations are performed, and the peak 1-g and 10-g SAR values are calculated. According to the peak SAR values, the maximum delivered power for the designed antenna was found so that the SAR values of the antenna satisfy the ANSI (American National Standards Institute) limitations.  相似文献   

Development of a plastic injection molding training system using Petri nets and virtual reality     

马斌  郭志英  周华民 《浙江大学学报(A卷英文版)》2006,7(3):302-308

INTRODUCTIONAt present, plastic as a substitute for metals in products is the most important mainstay in industrial raw materials. Furthermore, plastic injection molding is one of the most common and versatile methods for mass production of complex plastic parts with excel-lent dimensional tolerance. Since the technology of injection molding has been widely applied in manu-facturing, training on injection molding is of great importance. The traditional approach is to consult some technica…  相似文献   

一类三阶n点边值问题的正解的存在性     

王岩岩  刘伟  刘麦学 《洛阳师范学院学报》2011,30(2):1-7,35

令ai≥0,i=1,…,m-3且am-2>0.再令ξi满足0<ξ1<ξ2<…<ξm-2<1且∑m-2i=1aiξi<1.我们研究下面边值问题正解的存在性u?(t)+a(t)f(t)=0,t∈(0,1),u(0)=u′(0)=0,u′(1)=∑m-2i=1aiu′(ξi)其中a(t)∈C([0,1],[0,∞]),f(t)∈C([0,1],[0,∞]).通过锥上的不动点定理证明了在f满足超线性或次线性条件下,上述问题至少存在一个正解.  相似文献   

In the red? Debt levels at higher education institutions in China     

Daguang Wu  Kai Yu 《Asia Pacific Education Review》2011,12(3):329-336

Borrowing from banks has become a common practice among Chinese higher education institutions (HEIs), and operating with a heavy debt load has become a characteristic of Chinese higher educational development. Substantial financial commitments acquired by HEIs during their rapid expansion since 1998 are now having serious consequences: numerous universities and colleges have found themselves with major debt problems. Some are even facing insolvency. This paper describes the background of Chinese HEIs’ debt problems, assesses the present debt and repayment situation, and suggests a possible solution for the university debt crisis, using empirical evidence from one HEI in China.  相似文献   

Linkages between cognitive and social dialogue patterns during collaborative small-group discussions     

《Learning and Instruction》2023

BackgroundCollaborative small-group discussions have the potential to promote reading comprehension, critical thinking, and argumentation. However, few studies have gone beyond cognitive processes to understand the social characteristics of dialogue and their potential contributions to students’ cognitive processing in turn-by-turn dialogic exchanges.AimsThis study closely examined dialogues between speakers and addressees regarding their levels of cognitive processing (i.e., cognitive dialogue patterns) and social processes reflecting social cohesion (i.e., social dialogue patterns). The aims were to understand, first, the relations between students' cognitive dialogue patterns and their social dialogue patterns, and second, the relations between students' cognitive dialogue patterns and peers’ social dialogue patterns.SampleThis study included 4070 speaking turns generated by 120 fifth-graders in 60 small-group discussions.MethodsStudents participated in small-group discussions, called Collaborative Social Reasoning. Dialogue between pairs of group members formed social networks, based on which Exponential Random Graph Models (ERGMs) were specified.ResultsFindings showed that speakers' social dialogue patterns were associated with their cognitive dialogue patterns. However, receiving social dialogue patterns from peers did not always predict students’ advanced types of cognitive dialogue patterns.ConclusionsThis study demonstrated that cognitive and social aspects of small-group discussions are intricately linked, and that encouraging social cohesion does not guarantee that students will engage in collaborative and critical discussions.  相似文献   

Proteomic analysis of human umbilical vein endothelial cells exposed to PM<Subscript>2.5</Subscript>     

Ji Zhu  Lin-wen-si Zhu  Jin-huan Yang  Ying-ling Xu  Cui Wang  Zhuo-yu Li  Wei Mao  De-zhao Lu 《Journal of Zhejiang University. Science. B》2018,19(6):458-470

Exposure to fine ambient particulate matter (PM_2.5) is known to be associated with cardiovascular disease. To uncover the molecular mechanisms involved in cardiovascular toxicity of PM_2.5, we investigated alterations in the protein profile of human umbilical vein endothelial cells (HUVECs) treated with PM_2.5 using two-dimensional electrophoresis in conjunction with mass spectrometry (MS). A total of 31 protein spots were selected as differentially expressed proteins and identified by matrix-assisted laser desorption/ionization-time of flight (MALDI-TOF) MS. The results demonstrated that DNA damage and cell apoptosis are important factors contributing to PM_2.5-mediated toxicity in HUVECs. It is further proposed that PM_2.5 can inhibit superoxide dismutase (SOD) activity and increase reactive oxygen species (ROS) and malonaldehyde (MDA) production in a concentration-dependent manner. Induction of apoptosis and DNA damage through oxidative stress pathways may be one of the key toxicological events occurring in HUVECs under PM_2.5 stress. These results indicated that the toxic mechanisms of PM_2.5 on cardiovascular disease are related to endothelial dysfunction.  相似文献   

Approximate bang-bang control assisted rapid switching feedback stabilization for stochastic qubit systems     

《Journal of The Franklin Institute》2022,359(5):2073-2091

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