This paper proposes an estimation method of fracture resistance of oil ＆ gas pipes, based on the results of full scale hydraulic pressure pipe testing with the artificial notch, made by the authors at 2002-2006. It s...This paper proposes an estimation method of fracture resistance of oil ＆ gas pipes, based on the results of full scale hydraulic pressure pipe testing with the artificial notch, made by the authors at 2002-2006. It shows that the fracture process at the stage of stripping （initialization） of crack can be characterized by Critical Fracture Diagram （CFD）. Calculating and experimental way to construct CFD is suggested and discussed. The fracture resistance requirements for oil ＆ gas pipes in terms of fracture mechanics （Kc, Lc） are formulated and proved. The results of full scale hydraulic pressure pipe testing, based on metal testing data of the standard Charpy specimens （KCV） and pipe＇s specification requirements are interrelated. The way to estimate the admissible temperature operation conditions of oil ＆ gas pipes by means of based metal ＂KCV-temperature＂ dependence is proposed.展开更多
In this paper, on the basis of the implementation of the national chemical industry standard analytical test methods and analysis of test items, a food additive quality analysis and inspection of network management ap...In this paper, on the basis of the implementation of the national chemical industry standard analytical test methods and analysis of test items, a food additive quality analysis and inspection of network management applications are developed using the development technology of Visual Basic language and computer system operating environment, to achieve a network management software for users on food additives of quality analytical testing. The software sets up an information sharing network platform for enterprise and quality management departments, which is a major innovation in the food additive quality analysis on test management methods and tools.展开更多
Large-scale field shear tests on ten specimens of the red-sandstone embankment at a highway in Hunan,China,were performed to examine mechanical characteristics and parameters of red-sandstone.The curves of thrust-disp...Large-scale field shear tests on ten specimens of the red-sandstone embankment at a highway in Hunan,China,were performed to examine mechanical characteristics and parameters of red-sandstone.The curves of thrust-displacement,failure mode,and shear strength parameters for red-sandstone with different water contents,different compactions,and different grain size distributions were obtained from the tests.A practical procedure of in-situ test for red-sandstone embankment was proposed to normalize the test equipment and test steps.Based on three-dimensional thrust-sliding limit equilibrium method,the formulas for calculating strength parameters of red-sandstone considering three-dimensional sliding surface were inferred.The results show that red-sandstone has typical complete curves of stress-strain,strain softening,which are caused by the special structure of red-sandstone;water content and compaction are important factors for strength and failure mode of red-sandstone;The average value of cohesion and internal friction angle of the specimens calculated by three-dimensional technique are 21.56 kPa and 29.29°,respectively,and those by traditional two-dimensional method are 25.52 kPa and 33.76°,respectively.展开更多
Many websites use verification codes to prevent users from using the machine automatically to register,login,malicious vote or irrigate but it brought great burden to the enterprises involved in internet marketing as ...Many websites use verification codes to prevent users from using the machine automatically to register,login,malicious vote or irrigate but it brought great burden to the enterprises involved in internet marketing as entering the verification code manually.Improving the verification code security system needs the identification method as the corresponding testing system.We propose an anisotropic heat kernel equation group which can generate a heat source scale space during the kernel evolution based on infinite heat source axiom,design a multi-step anisotropic verification code identification algorithm which includes core procedure of building anisotropic heat kernel,settingwave energy information parameters,combing outverification codccharacters and corresponding peripheral procedure of gray scaling,binarizing,denoising,normalizing,segmenting and identifying,give out the detail criterion and parameter set.Actual test show the anisotropic heat kernel identification algorithm can be used on many kinds of verification code including text characters,mathematical,Chinese,voice,3D,programming,video,advertising,it has a higher rate of 25%and 50%than neural network and context matching algorithm separately for Yahoo site,49%and 60%for Captcha site,20%and 52%for Baidu site,60%and 65%for 3DTakers site,40%,and 51%.for MDP site.展开更多
Rational Univariate Representation （RUR） of zero-dimensional ideals is used to describe the zeros of zero-dimensional ideals and RUR has been studied extensively. In 1999, Roullier proposed an efficient algorithm to...Rational Univariate Representation （RUR） of zero-dimensional ideals is used to describe the zeros of zero-dimensional ideals and RUR has been studied extensively. In 1999, Roullier proposed an efficient algorithm to compute RUR of zero-dimensional ideals. In this paper, we will present a new algorithm to compute Polynomial Univariate Representation （PUR） of zero-dimensional ideals. The new algorithm is based on some interesting properties of Grobner basis. The new algorithm also provides a method for testing separating elements.展开更多
文摘This paper proposes an estimation method of fracture resistance of oil ＆ gas pipes, based on the results of full scale hydraulic pressure pipe testing with the artificial notch, made by the authors at 2002-2006. It shows that the fracture process at the stage of stripping （initialization） of crack can be characterized by Critical Fracture Diagram （CFD）. Calculating and experimental way to construct CFD is suggested and discussed. The fracture resistance requirements for oil ＆ gas pipes in terms of fracture mechanics （Kc, Lc） are formulated and proved. The results of full scale hydraulic pressure pipe testing, based on metal testing data of the standard Charpy specimens （KCV） and pipe＇s specification requirements are interrelated. The way to estimate the admissible temperature operation conditions of oil ＆ gas pipes by means of based metal ＂KCV-temperature＂ dependence is proposed.
文摘In this paper, on the basis of the implementation of the national chemical industry standard analytical test methods and analysis of test items, a food additive quality analysis and inspection of network management applications are developed using the development technology of Visual Basic language and computer system operating environment, to achieve a network management software for users on food additives of quality analytical testing. The software sets up an information sharing network platform for enterprise and quality management departments, which is a major innovation in the food additive quality analysis on test management methods and tools.
基金Project(200612) supported by Hunan Province Transportation Department of China
文摘Large-scale field shear tests on ten specimens of the red-sandstone embankment at a highway in Hunan,China,were performed to examine mechanical characteristics and parameters of red-sandstone.The curves of thrust-displacement,failure mode,and shear strength parameters for red-sandstone with different water contents,different compactions,and different grain size distributions were obtained from the tests.A practical procedure of in-situ test for red-sandstone embankment was proposed to normalize the test equipment and test steps.Based on three-dimensional thrust-sliding limit equilibrium method,the formulas for calculating strength parameters of red-sandstone considering three-dimensional sliding surface were inferred.The results show that red-sandstone has typical complete curves of stress-strain,strain softening,which are caused by the special structure of red-sandstone;water content and compaction are important factors for strength and failure mode of red-sandstone;The average value of cohesion and internal friction angle of the specimens calculated by three-dimensional technique are 21.56 kPa and 29.29°,respectively,and those by traditional two-dimensional method are 25.52 kPa and 33.76°,respectively.
基金The national natural science foundation(61273290,61373147)Xiamen Scientific Plan Project(2014S0048,3502Z20123037)+1 种基金Fujian Scientific Plan Project(2013HZ0004-1)FuJian provincial education office A-class project(-JA13238)
文摘Many websites use verification codes to prevent users from using the machine automatically to register,login,malicious vote or irrigate but it brought great burden to the enterprises involved in internet marketing as entering the verification code manually.Improving the verification code security system needs the identification method as the corresponding testing system.We propose an anisotropic heat kernel equation group which can generate a heat source scale space during the kernel evolution based on infinite heat source axiom,design a multi-step anisotropic verification code identification algorithm which includes core procedure of building anisotropic heat kernel,settingwave energy information parameters,combing outverification codccharacters and corresponding peripheral procedure of gray scaling,binarizing,denoising,normalizing,segmenting and identifying,give out the detail criterion and parameter set.Actual test show the anisotropic heat kernel identification algorithm can be used on many kinds of verification code including text characters,mathematical,Chinese,voice,3D,programming,video,advertising,it has a higher rate of 25%and 50%than neural network and context matching algorithm separately for Yahoo site,49%and 60%for Captcha site,20%and 52%for Baidu site,60%and 65%for 3DTakers site,40%,and 51%.for MDP site.
基金supported by National Key Basic Research Project of China(Grant No. 2011CB302400)National Natural Science Foundation of China (Grant Nos. 10971217,60821002/F02)
文摘Rational Univariate Representation （RUR） of zero-dimensional ideals is used to describe the zeros of zero-dimensional ideals and RUR has been studied extensively. In 1999, Roullier proposed an efficient algorithm to compute RUR of zero-dimensional ideals. In this paper, we will present a new algorithm to compute Polynomial Univariate Representation （PUR） of zero-dimensional ideals. The new algorithm is based on some interesting properties of Grobner basis. The new algorithm also provides a method for testing separating elements.
