When diffusing object is illuminated by a laser, it gives the impression of being covered with a very fine grain structure. This structure commonly is nothing but the result of the interference of random waves from th...When diffusing object is illuminated by a laser, it gives the impression of being covered with a very fine grain structure. This structure commonly is nothing but the result of the interference of random waves from the object. In the early years of the invention of the laser sources, the CND control was considered a birth which severely affects the image resolution. Various studies have been developed to remove. The development of new systems for capturing images CCD coupled with tools image processing techniques has made the CND control most interesting for industrial control real-time and non-destructive. Metrology of photography and optic interferometry are two methods that provide the ability to analyze and determine deformations of structures. The CND technique is the most answered and more particularly the technical of interferometry. This method is simple to implement, follow the evolution of the interference of a speckle fields diffracted by an object and a reference fields. Images are recorded by a CCD camera and digitally processed by computer to generate correlograms from which is extracted the gauging. CND techniques have provided only qualitative measures as correlation fringes. The application process and digital image processing techniques to measure phase yielded quantitative measures. Among the techniques for calculating phase, the phase shift method is the most used because it is the most accurate. This technique is based on a combination of shifted interferograms to extract the phase. It requires a phase modulator for generating phase-shifted interferograms speckle and an algorithm for calculating the phase.展开更多
Tests under mechanical strain control were performed to investigate the TMF behavior of Z2CND18.12N within the temperature range between 150–550 ？ C. Different strain amplitudes and phase-angles were applied. Total ...Tests under mechanical strain control were performed to investigate the TMF behavior of Z2CND18.12N within the temperature range between 150–550 ？ C. Different strain amplitudes and phase-angles were applied. Total strain controlled low cycle fatigue test was also performed at the peak temperature of TMF cycling. The results show that the cyclic stress response of the material displayed an initial hardening regime followed by a saturation period and then cyclic softening till failure. The TMF cycling leads to the development of significant amounts of mean stress. Some life prediction models were employed to predict the TMF life of Z2CND18.12N, and the results indicate that the energy-based models provide good prediction on the thermal-mechanical fatigue behaviors of this material. An optical microscopic observation shows that the surface crack initiations and crack propagations are typically transgranular mode.展开更多
目前计算机网络防御研究中缺乏高层且易于细化的策略建模方法,因此在分析Or-BAC模型(Organization Based Access Control model)的基础上,对网络防御控制行为进行抽象,建立计算机网络防御策略模型(CNDPM,Computer Network Defense Polic...目前计算机网络防御研究中缺乏高层且易于细化的策略建模方法,因此在分析Or-BAC模型(Organization Based Access Control model)的基础上,对网络防御控制行为进行抽象,建立计算机网络防御策略模型(CNDPM,Computer Network Defense Policy Model).该模型对保护、检测和响应等策略进行统一建模,并引入角色、视图、活动自动分配的方法,以提高分配的效率,同时给出了策略到规则的推导规则,以细化为具体的防御规则.还给出了策略的完备性、有效性和一致性的形式化描述及分析.实例分析表明,该模型表示的计算机网络防御策略,能够有效地转化为防御规则,具有较好的实用性和扩展性.展开更多
文摘When diffusing object is illuminated by a laser, it gives the impression of being covered with a very fine grain structure. This structure commonly is nothing but the result of the interference of random waves from the object. In the early years of the invention of the laser sources, the CND control was considered a birth which severely affects the image resolution. Various studies have been developed to remove. The development of new systems for capturing images CCD coupled with tools image processing techniques has made the CND control most interesting for industrial control real-time and non-destructive. Metrology of photography and optic interferometry are two methods that provide the ability to analyze and determine deformations of structures. The CND technique is the most answered and more particularly the technical of interferometry. This method is simple to implement, follow the evolution of the interference of a speckle fields diffracted by an object and a reference fields. Images are recorded by a CCD camera and digitally processed by computer to generate correlograms from which is extracted the gauging. CND techniques have provided only qualitative measures as correlation fringes. The application process and digital image processing techniques to measure phase yielded quantitative measures. Among the techniques for calculating phase, the phase shift method is the most used because it is the most accurate. This technique is based on a combination of shifted interferograms to extract the phase. It requires a phase modulator for generating phase-shifted interferograms speckle and an algorithm for calculating the phase.
基金supported by the National High Technical Research and Development Program of China (No.2009AA04Z403)PhD Programs Foundation of Ministry of Education of China (No.20090032110016)support (No.2010NGQ003) from Key Laboratory of Efficient & Clean Energy Utilization, College of Hunan Province
文摘Tests under mechanical strain control were performed to investigate the TMF behavior of Z2CND18.12N within the temperature range between 150–550 ？ C. Different strain amplitudes and phase-angles were applied. Total strain controlled low cycle fatigue test was also performed at the peak temperature of TMF cycling. The results show that the cyclic stress response of the material displayed an initial hardening regime followed by a saturation period and then cyclic softening till failure. The TMF cycling leads to the development of significant amounts of mean stress. Some life prediction models were employed to predict the TMF life of Z2CND18.12N, and the results indicate that the energy-based models provide good prediction on the thermal-mechanical fatigue behaviors of this material. An optical microscopic observation shows that the surface crack initiations and crack propagations are typically transgranular mode.
文摘目前计算机网络防御研究中缺乏高层且易于细化的策略建模方法,因此在分析Or-BAC模型(Organization Based Access Control model)的基础上,对网络防御控制行为进行抽象,建立计算机网络防御策略模型(CNDPM,Computer Network Defense Policy Model).该模型对保护、检测和响应等策略进行统一建模,并引入角色、视图、活动自动分配的方法,以提高分配的效率,同时给出了策略到规则的推导规则,以细化为具体的防御规则.还给出了策略的完备性、有效性和一致性的形式化描述及分析.实例分析表明,该模型表示的计算机网络防御策略,能够有效地转化为防御规则,具有较好的实用性和扩展性.
