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71.
Bergmeir C García Silvente M Benítez JM 《Computer methods and programs in biomedicine》2012,107(3):497-512
In order to automate cervical cancer screening tests, one of the most important and longstanding challenges is the segmentation of cell nuclei in the stained specimens. Though nuclei of isolated cells in high-quality acquisitions often are easy to segment, the problem lies in the segmentation of large numbers of nuclei with various characteristics under differing acquisition conditions in high-resolution scans of the complete microscope slides. We implemented a system that enables processing of full resolution images, and proposes a new algorithm for segmenting the nuclei under adequate control of the expert user. The system can work automatically or interactively guided, to allow for segmentation within the whole range of slide and image characteristics. It facilitates data storage and interaction of technical and medical experts, especially with its web-based architecture. The proposed algorithm localizes cell nuclei using a voting scheme and prior knowledge, before it determines the exact shape of the nuclei by means of an elastic segmentation algorithm. After noise removal with a mean-shift and a median filtering takes place, edges are extracted with a Canny edge detection algorithm. Motivated by the observation that cell nuclei are surrounded by cytoplasm and their shape is roughly elliptical, edges adjacent to the background are removed. A randomized Hough transform for ellipses finds candidate nuclei, which are then processed by a level set algorithm. The algorithm is tested and compared to other algorithms on a database containing 207 images acquired from two different microscope slides, with promising results. 相似文献
72.
The influence of music on mood and performance while driving 总被引:1,自引:0,他引:1
van der Zwaag MD Dijksterhuis C de Waard D Mulder BL Westerink JH Brookhuis KA 《Ergonomics》2012,55(1):12-22
Mood can influence our everyday behaviour and people often seek to reinforce, or to alter their mood, for example by turning on music. Music listening while driving is a popular activity. However, little is known about the impact of music listening while driving on physiological state and driving performance. In the present experiment, it was investigated whether individually selected music can induce mood and maintain moods during a simulated drive. In addition, effects of positive, negative, and no music on driving behaviour and physiological measures were assessed for normal and high cognitive demanding rides. Subjective mood ratings indicated that music successfully maintained mood while driving. Narrow lane width drives increased task demand as shown in effort ratings and increased swerving. Furthermore, respiration rate was lower during music listening compared to rides without music, while no effects of music were found on heart rate. Overall, the current study demonstrates that music listening in car influences the experienced mood while driving, which in turn can impact driving behaviour. PRACTITIONERS SUMMARY: Even though it is a popular activity, little is known about the impact of music while driving on physiological state and performance. We examined whether music can induce moods during high and low simulated drives. The current study demonstrates that in car music listening influences mood which in turn can impact driving behaviour. The current study shows that listening to music can positively impact mood while driving, which can be used to affect state and safe behaviour. Additionally, driving performance in high demand situations is not negatively affected by music. 相似文献
73.
74.
提出一种使用元启发搜索技术产生测试数据的方法。这种方法能够针对测试中低概率执行部分产生测试数据,提高测试覆盖率,并通过实验举例说明了该方法的可行性。 相似文献
75.
从电解铝工业生命周期评价看能源、环境对产业结构的制约 总被引:1,自引:0,他引:1
以货币量化为手段计算了电解铝工业生命周期内的主要污染排放造成的环境成本,并综合电解铝工业的生产成本、整个生命周期内能源耗费、环境成本衡量了电解铝厂的经济发展状况,进一步探讨了能源、环境对产业结构的制约。 相似文献
76.
Ben M Chen 《Systems & Control Letters》1997,32(2):619
A noniterative method for the computation of infimum for a class of continuous-time H∞ optimal control problem is considered in this paper. The problem formulation is fairly general and does not place any restrictions on any direct feedthrough terms of the given systems. The method is applicable to systems where (i) the transfer function from the disturbance input to the measurement output is free of imaginary axis invariant zeros and left invertible, and (ii) the transfer function from the control input to the controlled output of the given system is free of imaginary axis invariant zeros and right invertible. The result presented in this paper is a continuation of the previous work of the author and his co-workers (Chen et al., 1992), in which the direct feedthrough term from the disturbance input to the measurement output of the given system are required to be zero. 相似文献
77.
提高单片机系统可靠性的若干措施 总被引:1,自引:0,他引:1
由单片机构成的测控系统,大多应用于工业现场,存在着各种干扰。为保证微机系统可靠地工作,本文提出了若干提高单片机系统可靠性的措施,并进行了分析和介绍。 相似文献
78.
介绍了以MCS-51系列单片机为核心的定量检测系统的基本原理。并对其硬件结构和软件设计进行了详细地介绍。 相似文献
79.
用B3LYP/6 31 1 + +G 方法研究了H2 S与HO2 自由基之间的氢键。发现了三个能量极小点。同时做了H2 S·HO2 的振动频率分析。计算预测了能量整体最小点的构型为带有 2个扭曲的氢键的五元环结构 相似文献
80.