The R F first order second moment method will produce more error for calculating the reliability of welded engineering pipe structures when the failure function is seriously nonlinear and the random variables don...The R F first order second moment method will produce more error for calculating the reliability of welded engineering pipe structures when the failure function is seriously nonlinear and the random variables don′t serve as normal distribution. In order to increase the computing accuracy of reliability, an improved FOSM method is used for calculating the failure probability of welded pipes with flaws in this paper. Because of solving the problems of the linear expansion of failure function at the failure point and constructing equivalent normal variables, the new algorithm can greatly improve the calculating accuracy of probability of the welded pipes with cracks. The examples show that this method is simple, efficient and accurate for reliability safety assessment of the welded pipes with cracks. It can save more time than the Monte Carlo method does, so that the improved FOSM method is recommended for engineering reliability safety assessment of the welded pipes with flaws.展开更多
Region-Growing Algorithms （RGAs） are used to grade the quality of manufactured wood flooring. Traditional RGAs are hampered by prob- lems of long segmentation time and low inspection accuracy caused by neighborhood ...Region-Growing Algorithms （RGAs） are used to grade the quality of manufactured wood flooring. Traditional RGAs are hampered by prob- lems of long segmentation time and low inspection accuracy caused by neighborhood search. We used morphological reconstruction with the R com- ponent to construct a novel flaw segmentation method. We initially designed two template images for low and high thresholds, and these were used for seed optimization and inflation growth, respectively. Then the extraction of the flaw skeleton from the low threshold image was realized by applying the erosion termination rules. The seeds in the flaw skeleton were optimized by the pruning method. The geodesic inflection was applied by the high threshold template to realize rapid growth of the flaw area in the floor plate, and region filling and pruning operations were applied for margin optimization. Experi- ments were conducted on 512×512, 256×256 and 128×128 pixel sizes, re- spectively. The 256×256 pixel size proved superior in time-consumption at 0.06 s with accuracy of 100%. But with the region-growing method the same process took 0.22 s with accuracy of 70%. Compared with RGA, our pro- posed method can realize more accurate segmentation, and the speed and accuracy of segmentation can satisfy the requirements for on-line grading of wood flooring.展开更多
Emma is the heroine of one of the novels written by Jane Austen(1775-1817) who is among the most widely read writers in English literature.In the novel,also named Emma,Austen portrayed Emma as a young,pretty and smart...Emma is the heroine of one of the novels written by Jane Austen(1775-1817) who is among the most widely read writers in English literature.In the novel,also named Emma,Austen portrayed Emma as a young,pretty and smart gentlewoman,yet she was not a perfect or flawless character.She dose not seem to have any sense of her own limitations.Her self-conceit and meddling nature are two of her most fatal character flaws.In this article,we will give a detailed analysis of Emma's flaws supported by various incidents as the novel progresses.We will also find out the two major factors that contribute to develop these character flaws,which are the negative effects caused on her by people very close to her and also the society of her time.展开更多
This study aims to investigate the mechanical response and acoustic emission(AE)characteristic of pre-flawed sandstone under both monotonic and multilevel constant-amplitude cyclic loads.Specifically,we explored how c...This study aims to investigate the mechanical response and acoustic emission(AE)characteristic of pre-flawed sandstone under both monotonic and multilevel constant-amplitude cyclic loads.Specifically,we explored how coplanar flaw angle and load type impact the strength and deformation behavior and microscopic damage mechanism.Results indicated that being fluctuated before rising with increasing fissure angle under monotonic loading,the peak strength of the specimen first increased slowly and then steeply under cyclic loading.The effect of multilevel cyclic loading on the mechanical parameters was more significant.For a single fatigue stage,the specimen underwent greater deformation in early cycles,which subsequently stabilized.Similar variation pattern was also reflected by AE count/energy/b-value.Crack behaviors were dominated by the fissure angle and load type and medium-scale crack accounted for 74.83%–86.44%of total crack.Compared with monotonic loading,crack distribution of specimen under cyclic loading was more complicated.Meanwhile,a simple model was proposed to describe the damage evolution of sandstone under cyclic loading.Finally,SEM images revealed that the microstructures at the fracture were mainly composed of intergranular fracture,and percentage of transgranular fracture jumped under cyclic loading due to the rapid release of elastic energy caused by high loading rate.展开更多
Hamlet is the most discussed of Shakespeare's tragedies, while The Great Gatsby is the masterpiece of Fitzgerald. It is true that the tragic flaws of the protagonists would be a key factor driving the development ...Hamlet is the most discussed of Shakespeare's tragedies, while The Great Gatsby is the masterpiece of Fitzgerald. It is true that the tragic flaws of the protagonists would be a key factor driving the development of the plots. In these two dramas, the flaws of the protagonists leaded to their tragic endings which are related to their own characteristics of the protagonists. And the ends of the stories are with the tragedies.展开更多
A new method to detect steel ball's surface flaws is presented based on computer techniques of image processing and pattern recognition. The steel ball's surface flaws is the primary factor causing bearing fai...A new method to detect steel ball's surface flaws is presented based on computer techniques of image processing and pattern recognition. The steel ball's surface flaws is the primary factor causing bearing failure. The high efficient and precision detections for the surface flaws of steel ball can be conducted by the presented method, including spot, abrasion, burn, scratch and crack, etc. The design of main components of the detecting system is described in detail including automatic feeding mechanism, automatic spreading mechanism of steel ball's surface, optical system of microscope, image acquisition system, image processing system. The whole automatic system is controlled by an industrial control computer, which can carry out the recognition of flaws of steel ball's surface effectively.展开更多
The Spanish Tragedy, written by Thomas Kyd in the late 1580 s, was the grandfather of all revenge tragedies. It established a new genre named revenge tragedy in English theater. Its well-developed characters, timeless...The Spanish Tragedy, written by Thomas Kyd in the late 1580 s, was the grandfather of all revenge tragedies. It established a new genre named revenge tragedy in English theater. Its well-developed characters, timeless themes, dramatic intrigue and pioneering adoption of blank verse enabled it to be viewed as a classic of London theater. Yet it also has received criticisms over the past centuries. Based on Aristotle's opinion of a perfect tragedy in"Poetics", this paper aims to point out the flaws of the play from five perspectives: the fate of Hieronimo, the cause of it, Bel-imperia's sudden love for Horatio, subplot concerning Villuppo and Alexandro, the discovery and the diction.展开更多
文摘The R F first order second moment method will produce more error for calculating the reliability of welded engineering pipe structures when the failure function is seriously nonlinear and the random variables don′t serve as normal distribution. In order to increase the computing accuracy of reliability, an improved FOSM method is used for calculating the failure probability of welded pipes with flaws in this paper. Because of solving the problems of the linear expansion of failure function at the failure point and constructing equivalent normal variables, the new algorithm can greatly improve the calculating accuracy of probability of the welded pipes with cracks. The examples show that this method is simple, efficient and accurate for reliability safety assessment of the welded pipes with cracks. It can save more time than the Monte Carlo method does, so that the improved FOSM method is recommended for engineering reliability safety assessment of the welded pipes with flaws.
基金financially supported by the Fundamental Research Funds for the Central Universities(DL12EB04-03),(DL13CB02)the Natural Science Foundation of Heilongjiang Province(LC2011C25)
文摘Region-Growing Algorithms （RGAs） are used to grade the quality of manufactured wood flooring. Traditional RGAs are hampered by prob- lems of long segmentation time and low inspection accuracy caused by neighborhood search. We used morphological reconstruction with the R com- ponent to construct a novel flaw segmentation method. We initially designed two template images for low and high thresholds, and these were used for seed optimization and inflation growth, respectively. Then the extraction of the flaw skeleton from the low threshold image was realized by applying the erosion termination rules. The seeds in the flaw skeleton were optimized by the pruning method. The geodesic inflection was applied by the high threshold template to realize rapid growth of the flaw area in the floor plate, and region filling and pruning operations were applied for margin optimization. Experi- ments were conducted on 512×512, 256×256 and 128×128 pixel sizes, re- spectively. The 256×256 pixel size proved superior in time-consumption at 0.06 s with accuracy of 100%. But with the region-growing method the same process took 0.22 s with accuracy of 70%. Compared with RGA, our pro- posed method can realize more accurate segmentation, and the speed and accuracy of segmentation can satisfy the requirements for on-line grading of wood flooring.
文摘Emma is the heroine of one of the novels written by Jane Austen(1775-1817) who is among the most widely read writers in English literature.In the novel,also named Emma,Austen portrayed Emma as a young,pretty and smart gentlewoman,yet she was not a perfect or flawless character.She dose not seem to have any sense of her own limitations.Her self-conceit and meddling nature are two of her most fatal character flaws.In this article,we will give a detailed analysis of Emma's flaws supported by various incidents as the novel progresses.We will also find out the two major factors that contribute to develop these character flaws,which are the negative effects caused on her by people very close to her and also the society of her time.
基金This work was financially supported by the National Natural Science Foundation of China(Nos.42077231 and 51574156).
文摘This study aims to investigate the mechanical response and acoustic emission(AE)characteristic of pre-flawed sandstone under both monotonic and multilevel constant-amplitude cyclic loads.Specifically,we explored how coplanar flaw angle and load type impact the strength and deformation behavior and microscopic damage mechanism.Results indicated that being fluctuated before rising with increasing fissure angle under monotonic loading,the peak strength of the specimen first increased slowly and then steeply under cyclic loading.The effect of multilevel cyclic loading on the mechanical parameters was more significant.For a single fatigue stage,the specimen underwent greater deformation in early cycles,which subsequently stabilized.Similar variation pattern was also reflected by AE count/energy/b-value.Crack behaviors were dominated by the fissure angle and load type and medium-scale crack accounted for 74.83%–86.44%of total crack.Compared with monotonic loading,crack distribution of specimen under cyclic loading was more complicated.Meanwhile,a simple model was proposed to describe the damage evolution of sandstone under cyclic loading.Finally,SEM images revealed that the microstructures at the fracture were mainly composed of intergranular fracture,and percentage of transgranular fracture jumped under cyclic loading due to the rapid release of elastic energy caused by high loading rate.
文摘Hamlet is the most discussed of Shakespeare's tragedies, while The Great Gatsby is the masterpiece of Fitzgerald. It is true that the tragic flaws of the protagonists would be a key factor driving the development of the plots. In these two dramas, the flaws of the protagonists leaded to their tragic endings which are related to their own characteristics of the protagonists. And the ends of the stories are with the tragedies.
基金Sponsored by Technology Project Itemof Department of Education of Jilin Province (2006JYT02)
文摘A new method to detect steel ball's surface flaws is presented based on computer techniques of image processing and pattern recognition. The steel ball's surface flaws is the primary factor causing bearing failure. The high efficient and precision detections for the surface flaws of steel ball can be conducted by the presented method, including spot, abrasion, burn, scratch and crack, etc. The design of main components of the detecting system is described in detail including automatic feeding mechanism, automatic spreading mechanism of steel ball's surface, optical system of microscope, image acquisition system, image processing system. The whole automatic system is controlled by an industrial control computer, which can carry out the recognition of flaws of steel ball's surface effectively.
文摘The Spanish Tragedy, written by Thomas Kyd in the late 1580 s, was the grandfather of all revenge tragedies. It established a new genre named revenge tragedy in English theater. Its well-developed characters, timeless themes, dramatic intrigue and pioneering adoption of blank verse enabled it to be viewed as a classic of London theater. Yet it also has received criticisms over the past centuries. Based on Aristotle's opinion of a perfect tragedy in"Poetics", this paper aims to point out the flaws of the play from five perspectives: the fate of Hieronimo, the cause of it, Bel-imperia's sudden love for Horatio, subplot concerning Villuppo and Alexandro, the discovery and the diction.
