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Effects of a reagent’s rotational and vibrational excitations on reaction O(~3P) + H_2 (ν=0,3,j = 0,3,5,7,9,12,15) → OH+H
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作者 许增慧 宗福建 +3 位作者 韩博然 董少华 刘建强 计峰 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第9期187-195,共9页
To investigate the effect of a reagent's rotational and vibrational excitations on the stereo-dynamics of the reaction product, the title reaction is theoretically simulated using the quasi-classical trajectory (QCT... To investigate the effect of a reagent's rotational and vibrational excitations on the stereo-dynamics of the reaction product, the title reaction is theoretically simulated using the quasi-classical trajectory (QCT) method on the 3A~ and 3Aq potentiM energy surfaces (PESs). The reaction cross section is considered as the only scalar property in this work at four different collision energies. Furthermore the vector properties including two polarization-dependent differential cross sections (PDDCSs), the angular distributions of product' rotational momentum are discussed at one fixed collision energy. Effects of reagents' rotational excitation on the reaction do exist regularly. 展开更多
关键词 chemical stereo-dynamics quasi-classical trajectory calculation vector correlation ro- tational and vibrational excitations
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Rapid State Augmentation for Compressed EKF-Based Simultaneous Localization and Mapping 被引量:1
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作者 窦丽华 张海强 +1 位作者 陈杰 方浩 《Journal of Beijing Institute of Technology》 EI CAS 2009年第2期192-197,共6页
A new method for speeding up the state augment operations involved in the compressed extended Kalman filter-based simultaneous localization and mapping (CEKF-SLAM) algorithm was proposed. State augment usually requi... A new method for speeding up the state augment operations involved in the compressed extended Kalman filter-based simultaneous localization and mapping (CEKF-SLAM) algorithm was proposed. State augment usually requires a fully-updated state eovariance so as to append the information of newly observed landmarks, thus computational volume increases quadratically with the number of landmarks in the whole map. It was proved that state augment can also be achieved by augmenting just one auxiliary coefficient ma- trix. This method can yield identical estimation results as those using EKF-SLAM algorithm, and computa- tional amount grows only linearly with number of increased landmarks in the local map. The efficiency of this quick state augment for CEKF-SLAM algorithm has been validated by a sophisticated simulation project. 展开更多
关键词 simultaneous localization and mapping (SLAM) extended Kalman filter state augment compu- tational volume
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HOT DUCTILITY OF 304HC STAINLESS STEEL AND THE MODEL OF RESISTANCE TO DEFORMATION 被引量:5
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作者 H.S.Di G.Z.Cui +1 位作者 G.D.Wang X.H.Liu 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2003年第2期97-103,共7页
The ductility map of 304HC stainless was determined by using the Gleeble-1500 dynamic thermal-mechanical simulator. The effect of Cu on the hot ductility of 304HC stainless steel was analyzed and the mathematical mode... The ductility map of 304HC stainless was determined by using the Gleeble-1500 dynamic thermal-mechanical simulator. The effect of Cu on the hot ductility of 304HC stainless steel was analyzed and the mathematical model of resistance to deformation was established. The microstructure, inclusion and fracture surface were studied by using the method of micro structure analysis, scanning, energy spectrum and electron microscope. The results show that Cu has effect on the hot ductility, and the hot ductility of 304HC stainless steel decrease with the increase of content of Cu. The deformation temperature also has much effect on the hot ductility, the suitable deformation temperature are 1100-1200℃. The reason of it is that the Cu rich chemical compounds were precipitated from austenite phase during cooling. The Cu rich chemical compounds are brittle substance such as Cu2S, Cu2O and ε-Cu etc. 展开更多
关键词 304HC stainless steel hot ductility brittle compounds precipi- tation mathematical model resistance to deformation
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The Extreme Summer Precipitation over East China during 1982-2007 Simulated by the LASG/IAP Regional Climate Model 被引量:6
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作者 LIU Jing-Wei LI Bo +2 位作者 ZHOU Tian-Jun ZENG Xian-Feng FENG Lei 《Atmospheric and Oceanic Science Letters》 2012年第1期62-67,共6页
The extreme summer precipitation over East China during 1982-2007 was simulated using the LASG/IAP regional climate model CREM(the Climate version of a Regional Eta-coordinate Model).The results show that the probabil... The extreme summer precipitation over East China during 1982-2007 was simulated using the LASG/IAP regional climate model CREM(the Climate version of a Regional Eta-coordinate Model).The results show that the probability density functions(PDFs) of precipitation intensities are reasonably simulated,except that the PDFs of light and moderate rain are underestimated and that the PDFs of heavy rain are overestimated.The extreme precipitation amount(R95p) and the percent contribution of extreme precipitation to the total precipitation(R95pt) are also reasonably reproduced by the CREM.However,the R95p and R95pt over most of East China are generally overestimated,while the R95p along the coastal area of South China(SC) is underestimated.The bias of R95pt is consistent with the bias of precipitation intensity on wet days(SDII).The interannual variation for R95p anomalies(PC1) is well simulated,but that of R95pt anomalies(PC2) is poorly simulated.The skill of the model in simulating PC1(PC2) increases(decreases) from north to south.The bias of water vapor transport associated with the 95th percentile of summer daily precipitation(WVTr95) explains well the bias of the simulated extreme precipitation. 展开更多
关键词 regional climate simulation extreme precipi- tation East China CREM
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Restoration of space-variant blurred image based on motion-blurred target segmentation 被引量:4
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作者 Yuye Zhang Xuewei Wang Chunxin Wang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2010年第2期191-196,共6页
In imaging on moving target, it is easy to get space- variant blurred image. In order to recover the image and gain recognizable target, an approach to recover the space-variant blurred image is presented based on ima... In imaging on moving target, it is easy to get space- variant blurred image. In order to recover the image and gain recognizable target, an approach to recover the space-variant blurred image is presented based on image segmentation. Be- cause of motion blur's convolution process, the pixels of observed image's target and background will be displaced and piled up to produce two superposition regions. As a result, the neighbor- ing pixels in the superposition regions will have similar grey level change. According to the pixel's motion-blur character, the target's blurred edge of superposition region could be detected. Canny operator can be recurred to detect the target edge which parallels the motion blur direction. Then in the segmentation process, the whole target image which has the character of integral convolution between motion blur and real target image can be obtained. At last, the target image is restored by deconvolution algorithms with adding zeros. The restoration result indicates that the approach can effectively solve the kind of problem of space-variant motion blurred image restoration. 展开更多
关键词 image restoration space-variant blur image segmen- tation motion-blur.
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Research on Production Conditions of Highgrade Wine from Northern Blueberry
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作者 刘炎赫 黄鑫宝 +2 位作者 王浩 徐文文 谭秀山 《Agricultural Science & Technology》 CAS 2016年第2期417-419,448,共4页
In order to develop the best brewing condition for high-grade fruit wine from northern blueberry, on the basis of reviewing literatures about blueberry wine manufacturing process, this study put forward a new technolo... In order to develop the best brewing condition for high-grade fruit wine from northern blueberry, on the basis of reviewing literatures about blueberry wine manufacturing process, this study put forward a new technological process, including raw materials-juicing-addition of auxiliary materials including pectinase-primary fer- mentation with yeast-post-fermentation-hot and cold treatment-sterilization-packaging- finished product, and sensory indexes, physicochemical indexes and hygienic index- es of the product were inspected according to corresponding national standards and industry standards. The results showed that for northern blueberry pulp, the optimal addition amount of yeast was 1.1 g/L, the fermentation temperature was 22 ℃, and the addition amounts of pectinase and sulfurous acid were 0.3 ml/kg and 100 ppm, respectively; the alcohol degree of the finished product was adjusted to 15.6°; and alternated cold and heat treatment used instead of conventional clarifying agent for removing colloid-like impurities resulted in the brewed product with good wine fra- grance, taste and color. 展开更多
关键词 BLUEBERRY Juicing PECTINASE YEAST Primary fermentation Post-fermen- tation Cold and heat treatment
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Vehicle Representation and Classification of Surveillance Video Based on Sparse Learning 被引量:2
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作者 CHEN Xiangjun RUAN Yaduan +2 位作者 ZHANG Peng CHEN Qimei ZHANG Xinggan 《China Communications》 SCIE CSCD 2014年第A01期135-141,共7页
We cast vehicle recognition as problem of feature representation and classification, and introduce a sparse learning based framework for vehicle recognition and classification in this paper. After objects captured wit... We cast vehicle recognition as problem of feature representation and classification, and introduce a sparse learning based framework for vehicle recognition and classification in this paper. After objects captured with a GMM background subtraction program, images are labeled with vehicle type for dictionary learning and decompose the images with sparse coding (SC), a linear SVM trained with the SC feature for vehicle classification. A simple but efficient active learning stategy is adopted by adding the false positive samples into previous training set for dictionary and SVM model retraining. Compared with traditional feature representation and classification realized with SVM, SC method achieves dramatically improvement on classification accuracy and exhibits strong robustness. The work is also validated on real-world surveillance video. 展开更多
关键词 vehicle classification feature represen- tation sparse learning robustness and generalization
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RESEARCHES ON INVERSE ORDER RULE FOR WEIGHTED GENERALIZED INVERSE
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作者 孙文瑜 魏益民 《Numerical Mathematics A Journal of Chinese Universities(English Series)》 SCIE 2000年第2期234-240,共7页
The weighted generalized inverses have several important applications in researching the singular matrices,regularization methods for ill-posed problems, optimization problems and statis- tics problems.In this paper w... The weighted generalized inverses have several important applications in researching the singular matrices,regularization methods for ill-posed problems, optimization problems and statis- tics problems.In this paper we further research inverse order rules of weighted generalizde inverse. From the view point of munerical algebra, the different methods we used in inverse order rules pro- vide beneficial means for theory and computing of generalized inverse matrices. 展开更多
关键词 GENERALIZED INVERSE WEIGHTED GENERALIZED INVERSE INVERSE order RULE MATRIX compu- tation
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Valence Control of Ce Ions in Cerium-substituted Yttrium Iron Garnet
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作者 宋锋兵 李强 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2005年第1期6-8,共3页
Cerium-substituted yttrium iron garnet(Ce x Y 3-xFe 5O 12, Ce∶YIG) was prepared via coprecipitation. The structu re, morphology, valence state and constituent of Ce ions were investigated respe ctively. X-ra... Cerium-substituted yttrium iron garnet(Ce x Y 3-xFe 5O 12, Ce∶YIG) was prepared via coprecipitation. The structu re, morphology, valence state and constituent of Ce ions were investigated respe ctively. X-ray powder diffraction(XRD) analysis shows that Ce∶YIG was of singl e cubic YIG phase. The result of X-ray photoelectron spectroscopy(XPS) indicate s the Ce ions in Ce∶YIG were in the state of trivalence. Scanning electron micr oscope(SEM) demonstrates the conglobation of Ce∶YIG particles about 0.2μm scal e.The magnetic properties were studied by a vibrating sample magnetometer(VSM) a nd the result exhibits that substitution of Ce 3+ changes the magnetic para meters of YIG. The effects of doping content of Ce ions and synthesis temperatu re on valence control were discussed in detail. 展开更多
关键词 cerium-substituted yttrium iron garnet coprecipi tation valence control Ce 3+
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Efficient Security Sequencing Problem over Insecure Channel Based on Homomorphic Encryption
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作者 Mingxu Yi Lifeng Wang Yunpeng Ma 《China Communications》 SCIE CSCD 2016年第9期195-202,共8页
In the field of sequencing of secret number,an important problem is how to establish an efficient and secure protocol for sorting the secret number.As a powerful tool in solving privacy sequencing problems,secure mult... In the field of sequencing of secret number,an important problem is how to establish an efficient and secure protocol for sorting the secret number.As a powerful tool in solving privacy sequencing problems,secure multipart computation is more and more popular in anonymous voting and online auction.In the present study,related secure computation protocol for sequencing problem is not many by far.In order to improve the efficiency and safety,we propose a security sequencing protocol based on homomorphic encryption.We also give analysis of correctness and security to highlight its feasibility. 展开更多
关键词 homomorphic encryption privacy sequencing problem secure multipart compu- tation information transformation
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Ab initio Calculations of Electron-Impact Excitation Cross Sections for N_2 Molecule
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作者 信裕 丁洪斌 《Plasma Science and Technology》 SCIE EI CAS CSCD 2014年第2期104-109,共6页
One of the great difficulties in understanding nitrogen plasma elementary processes is the lack of an available database of the cross-sections of electron-impact excitations and radiations. Ab initio calculations of v... One of the great difficulties in understanding nitrogen plasma elementary processes is the lack of an available database of the cross-sections of electron-impact excitations and radiations. Ab initio calculations of vibrational excitation cross sections for electron collisions with nitrogen molecules in low-lying states using similarity function approach, such as a-a', a-w, B-B' and B-W transition systems, are reported here for the first time. In the meantime, the average excitation energies of neighboring levels of these systems have been calculated. In order to obtain the cross sections, accurate spectroscopic constants and transition dipole moments have been investigated. Potential energy curves and other electronic transition dipole moments for the low-lying states of N2 have been re-evaluated using complete active space self-consistent field (CASSCF) approach with aug-cc-pVqZ basis set. The calculated cross-sections could provide a database for studying the elementary processes and the properties in N2 plasma. 展开更多
关键词 N2 potential energy curves transition dipole moments electron-impact exci- tation cross sections
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An Approach to Representing Heterogeneous Non-Uniform Rational B-Spline Objects
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作者 臧婷 徐安平 《Transactions of Tianjin University》 EI CAS 2011年第4期275-279,共5页
The representation method of heterogeneous material information is one of the key technologies of heterogeneous object modeling, but almost all the existing methods cannot represent non-uniform rational B-spline (NU... The representation method of heterogeneous material information is one of the key technologies of heterogeneous object modeling, but almost all the existing methods cannot represent non-uniform rational B-spline (NURBS) entity. According to the characteristics of NURBS, a novel data structure, named NURBS material data structure, is proposed, in which the geometrical coordinates, weights and material coordinates of NURBS heterogene- ous objects can be represented simultaneously. Based on this data structure, both direct representation method and inverse construction method of heterogeneous NURBS objects are introduced. In the direct representation method, three forms of NURBS heterogeneous objects are introduced by giving the geometry and material information of con- trol points, among which the homogeneous coordinates form is employed for its brevity and easy programming. In the inverse construction method, continuous heterogeneous curves and surfaces can he obtained by interpolating discrete points and curves with specified material information. Some examples are given to show the effectiveness of the pro- posed methods. 展开更多
关键词 heterogeneous object non-uniform rational B-spline (NURBS) material data structure direct represen- tation method inverse construction method
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An experimental indoor phasing system based on active optics using dispersed Hartmann sensing technology in the visible waveband
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作者 Yong Zhang Gen-Rong Liu +5 位作者 Yue-Fei Wang Ye-Ping Li Ya-Jun Zhang Liang Zhang Yi-Zhong Zeng Jie Zhang 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2011年第9期1111-1122,共12页
A telescope with a larger primary mirror can collect much more light and resolve objects much better than one with a smaller mirror, and so the larger version is always pursued by astronomers and astronomical technici... A telescope with a larger primary mirror can collect much more light and resolve objects much better than one with a smaller mirror, and so the larger version is always pursued by astronomers and astronomical technicians. Instead of using a monolithic primary mirror, more and more large telescopes, which are currently being planned or in construction, have adopted a segmented primary mirror design. Therefore, how to sense and phase such a primary mirror is a key issue for the future of extremely large optical/infrared telescopes. The Dispersed Fringe Sensor (DFS), or Dispersed Hartmann Sensor (DHS), is a non-contact method using broadband point light sources and it can estimate the piston by the two-directional spectrum formed by the transmissive grating's dispersion and lenslet array. Thus it can implement the combination of co-focusing by Shack-Hartmann technology and phasing by dispersed fringe sensing technologies such as the template-mapping method and the Hartmann method. We introduce the successful design, construction and alignment of our dis- persed Hartmann sensor together with its design principles and simulations. We also conduct many successful real phasing tests and phasing corrections in the visible waveband using our existing indoor segmented mirror optics platform. Finally, some conclusions are reached based on the test and correction of experimental results. 展开更多
关键词 astronomical instrumentation -- methods and techniques -- instrumen- tation: active optics -- adaptive optics
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Phosphatase and Tensin Homologue Genetic Polymorphisms and their Interactions with Viral Mutations on the Risk of Hepatocellular Carcinoma 被引量:5
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作者 Yan Du Yu-Wei Zhang +5 位作者 Rui Pu Xue Han Jian-Ping Hu Hong-Wei Zhang Hong-Yang Wang Guang-Wen Cao 《Chinese Medical Journal》 SCIE CAS CSCD 2015年第8期1005-1013,共9页
Background: Chronic hepatitis B virus (HBV) infection is the major cause of hepatocellular carcinoma (HCC). Some HBV mutants and dysregulation of phosphatase and tensin homolog (PTEN) may promote the developmen... Background: Chronic hepatitis B virus (HBV) infection is the major cause of hepatocellular carcinoma (HCC). Some HBV mutants and dysregulation of phosphatase and tensin homolog (PTEN) may promote the development of HCC synergistically. We aimed to test the effects of PTEN genetic polymorphisms and their interactions with important HBV mutations on the development of HCC in HBV-infected subjects. Methods: Quantitative po[ymerase chain reaction was applied to genotype PTEN polymorphisms (rs1234220, rs2299939, rsl234213) in 1012 healthy controls, 302 natural clearance subjects, and 2011 chronic H BV-infected subjects including 1021 HCC patients. HBV mutations were determined by sequencing. The associations of PTEN polymorphisms and their interactions with HBV mutations with HCC risk were assessed using multivariate logistic regression analysis. Results: Rs1234220 C allele was significantly associated with HCC risk compared to healthy controls (adjusted odds ratio [AOR] = 1.35, 95% confidence interval [CI] = 1,07-1.69) and HCC-free HBV-infected subjects (AOR = 1.27, 95% CI = 1.01-1 .57). rsl234220 C allele was significantly associated with increased frequencies of HCC-risk A 1652G, C 1673T, and C 1730G mutations in genotype B H BV-in fected subjects. Rs2299939 GT genotype was inversely associated with HCC risk in HBV-infected patients (AOR 0.75, 95% CI 0.62-0.92). The interaction of rs2299939 variant genotypes (GT+TT) with A3054T mutation significantly increased HCC risk (AOR = 2.41, 95% CI = 1.08-5.35); whereas its interaction with C3116T mutation significantly reduced HCC risk (AOR = 0.34, 95% CI 0.18-0.66). These significant effects were only evident in males alter stratification. Conclusions: PTEN polymorphisms and their interactions with HBV mutations may contribute to hepatocarcinogenesis in males. The host-virus interactions are important in identifying HBV-infected subjects who are more likely to develop HCC. 展开更多
关键词 Hepatitis B Virus Hepatocellular Carcinoma Polymorphism Phosphatase and Tensin Homolog Viral Mt tation
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Huashan Hospital Clinical Laboratory receives accredi- tation from College of American Pathologists
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《Chinese Medical Journal》 SCIE CAS CSCD 2006年第11期952-952,共1页
Huashan Hospital Clinical Laboratory, Shanghai, China, has been awarded an accreditation by the Commission on Laboratory Accreditation of the College of American Pathologists (CAP), based on the results of a recent ... Huashan Hospital Clinical Laboratory, Shanghai, China, has been awarded an accreditation by the Commission on Laboratory Accreditation of the College of American Pathologists (CAP), based on the results of a recent on-site inspection. 展开更多
关键词 Huashan Hospital Clinical Laboratory receives accredi tation from College of American Pathologists
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