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81.
This work investigates applicability of magnetic hysteresis method for non-destructive testing of plastically deformed low-carbon steel. Recently introduced Magnetic Adaptive Testing procedure was used for evaluation of hysteresis minor loop data-sets to find the most sensitive parameter/s for indication of the material degradation stage. Inductive measurements were carried out on two identically degraded series of samples: magnetically closed window-shaped specimens, equipped with the magnetizing and the induction coils, and magnetically open strips, measured by an attached magnetizing yoke. The aim was to compare the results between these sample series in order to determine applicability and limitations of the single-yoke measurement technique. As a result, new magnetic parameters with the best sensitivity–stability ratio in a wide deformation range were introduced and proposed for utilization. Good qualitative coincidence between the measurement results on the closed and the open sample series was obtained in all range of magnetization. Several quantitative distinctions were explained and analyzed in order to improve the single-yoke technique. 相似文献
82.
The 3D Morphable Model (3DMM) and the Structure from Motion (SfM) methods are widely used for 3D facial reconstruction from 2D single-view or multiple-view images. However, model-based methods suffer from disadvantages such as high computational costs and vulnerability to local minima and head pose variations. The SfM-based methods require multiple facial images in various poses. To overcome these disadvantages, we propose a single-view-based 3D facial reconstruction method that is person-specific and robust to pose variations. Our proposed method combines the simplified 3DMM and the SfM methods. First, 2D initial frontal Facial Feature Points (FFPs) are estimated from a preliminary 3D facial image that is reconstructed by the simplified 3DMM. Second, a bilateral symmetric facial image and its corresponding FFPs are obtained from the original side-view image and corresponding FFPs by using the mirroring technique. Finally, a more accurate the 3D facial shape is reconstructed by the SfM using the frontal, original, and bilateral symmetric FFPs. We evaluated the proposed method using facial images in 35 different poses. The reconstructed facial images and the ground-truth 3D facial shapes obtained from the scanner were compared. The proposed method proved more robust to pose variations than 3DMM. The average 3D Root Mean Square Error (RMSE) between the reconstructed and ground-truth 3D faces was less than 2.6 mm when 2D FFPs were manually annotated, and less than 3.5 mm when automatically annotated. 相似文献
83.
84.
对比研究了单种群遗传算法和多种群遗传算法在分段Chen系统参数估计中的应用,通过构造一个合适的适应度函数,将Chen系统的多参数估计问题转化成一个多参数的寻优问题,利用遗传算法全局寻优性对其进行计算。仿真结果表明,相对于采用单种群遗传算法估计分段Chen系统参数,多种群遗传算法在准确性、鲁棒性方面具有明显的优势。 相似文献
85.
Suehye Park Edward Namkyu Cho Ilgu Yun 《Journal of the Society for Information Display》2013,21(8):333-338
Amorphous In–Ga–Zn–O thin‐film transistors (TFTs) have attracted increasing attention due to their electrical performance and their potential for use in transparent and flexible devices. Because TFTs are exposed to illumination through red, green, and blue color filters, wavelength‐varied light illumination tests are required to ensure stable TFT characteristics. In this paper, the effects of different light wavelengths under both positive and negative VGS stresses on amorphous In–Ga–Zn–O TFTs are investigated. The TFT instability that is dependent on optical and electrical stresses can be explained by the charge trapping mechanism and interface modification. 相似文献
86.
吴公莹 《计算机光盘软件与应用》2011,(15)
当为了支持商业进程而沿伸IT系统时,用户和系统管理员为了完成工作,面对着日益增长的复杂的各种接口(人机交互接口)。用户需要登录多个的系统,而系统管理员则需要以同样的方式,维护多个系统的用户账号。单点登陆系统能集统一各个系统的认证和授权,解决用户和管理员的困扰,并大大提高安全性。利用Kerberos思想和SSL技术,在HTTP协议基础上建立有效的认证和授权机制,提出可行的Web单点登陆平台解决方案。 相似文献
87.
应用计算机、单片机和VB高级语言设计的光敏二极管特性测试装置,可以分析光敏二极管的工作原理、基本性能及其伏安特性,能够实现特性测试的全自动化,是研究光敏二极管特性的智能测试装置。 相似文献
88.
Hamidreza Rashidy Kanan Author Vitae 《Pattern recognition》2008,41(12):3799-3812
Though numerous approaches have been proposed for face recognition, little attention is given to the moment-based face recognition techniques. In this paper we propose a novel face recognition approach based on adaptively weighted patch pseudo Zernike moment array (AWPPZMA) when only one exemplar image per person is available. In this approach, a face image is represented as an array of patch pseudo Zernike moments (PPZM) extracted from a partitioned face image containing moment information of local areas instead of global information of a face. An adaptively weighting scheme is used to assign proper weights to each PPZM to adjust the contribution of each local area of a face in terms of the quantity of identity information that a patch contains and the likelihood of a patch is occluded. An extensive experimental investigation is conducted using AR and Yale face databases covering face recognition under controlled/ideal conditions, different illumination conditions, different facial expressions and partial occlusion. The system performance is compared with the performance of four benchmark approaches. The encouraging experimental results demonstrate that moments can be used for face recognition and patch-based moment array provides a novel way for face representation and recognition in single model databases. 相似文献
89.
We consider a single machine scheduling problem with simple linear deterioration. Job processing times are assumed to be a simple linear function of a job-dependent growth rate and the job's starting time. We seek an optimal schedule, so as to minimize the total absolute deviation of completion times (TADC). We prove several interesting properties of an optimal schedule, and introduce two efficient heuristics which are tested against a lower bound. 相似文献
90.
This paper considers single-machine scheduling problems with deteriorating jobs, i.e., jobs whose processing times are an increasing function of their starting times. In addition, the jobs are related by a series–parallel graph. It is shown that for the general linear problem to minimize the makespan, polynomial algorithms exist. It is also shown that for the proportional linear problem of minimization of the total weighted completion time, polynomial algorithms exist, too. 相似文献