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61.
基于叶片形态特征的葡萄品种自动识别 总被引:1,自引:0,他引:1
葡萄在全世界种植范围较广,葡萄品种识别对葡萄资源统计、新品种鉴定及遗传资源保护都有重要意义。以成熟叶片为基本材料,不变矩、面积、周长、主叶脉长度和叶柄长度等11维特征向量为基础数据,采用叶片特征选择、图像处理、特征值提取、建立分类模型等方法,运用国际葡萄与葡萄酒组织形态分类方法和改进的欧式距离等技术开发一个基于葡萄叶片数字图像的葡萄品种自动识别软件。共测试17种酿酒和3种野生葡萄,识别率达87%。该方法具有自动化、识别速度快、花费低、省时省力等特点,可应用于葡萄病虫害的识别、杂交新品种双亲的判定等。 相似文献
62.
林军雄 《计算机光盘软件与应用》2012,(3):186-187
论文首先对人脸识别进行了介绍,通过对人脸识别系统的分析指出预处理在人脸识别中的重要性。然后对已有的人脸识别预处理法作了详细的介绍,并对各种方法进行比较。最后针对光照对人脸图像的影响还提出了同态滤波的方法,在预处理阶段消除光照对人脸图像的影响,实验结果表明,此种方法可以提高识别率。 相似文献
63.
传统的基于微机的车牌识别系统的方案,使得评价识别效果的识别速率和识别成功率两个重要指标相互冲突.为了解决这个问题,很多文章提出了改进算法来调和识别算法的计算量和识别的成功率,但却没有考虑识别系统的成本问题.提出了一个基于DSP CPLD的硬件识别平台,可以大大提高各种识别算法的适应性和降低系统成本. 相似文献
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65.
Two parasitic angiosperms,Agalinis purpurea (Scrophulariaceae) andStriga asiatica (Scrophulariaceae), are compared as to the chemical recognition events involved in host selection.Agalinis is a hemiparasite which can mature to seed-set without a host, whereasStriga is a holoparasite and survives for only a very limited time without a host. Both parasites, however, attach to a host through a specialized organ known as the haustorium and regulate the development of this organ through the recognition of chemical factors from host plants. We now describe the discovery of 2,6-dimethoxy-p-benzoquinone (2,6-DMBQ) as an haustoria-inducing principle fromSorghum root extracts. Our investigation of this compound has led us to suggest that one level of host recognition in these parasitic plants is mediated through their enzymatic digestion of the host root surface. Degradation of surface components liberates quinonoid compounds, such as 2,6-DMBQ, which in turn trigger haustorial development. 相似文献
66.
The effectiveness of an active shutter-glasses stereoscopic display (SD) and a passive polarised SD was evaluated in a live robot-teleoperation task and a simulated indirect-vision driving task in various terrains. Overall, participants completed their tasks significantly faster with the SDs in three-dimensional (3D) mode than with the SDs in the baseline 2D mode. They also navigated more accurately with the SDs in 3D mode. When the effectiveness of the two types of SDs was examined separately, results showed that the active shutter-glasses SD resulted in faster responses and task completion times than the passive polarised SD, though most of the differences failed to reach statistical significance. Perceived workload when interacting with the two SD systems did not differ significantly between the active versus passive display types or between the 3D and 2D modes of operation; however, participants reported more severe discomfort after interacting with the passive polarised SD. 相似文献
67.
Providing an easy ingress–egress (I/E) movement remains a challenge for car designers. I/E has been largely studied in kinematics, but not in dynamics. This study proposes: (1) to evaluate and describe the motor torques developed in the lower limbs and lumbar joints during I/E motions and (2) to analyse the influence of the car geometry and subject anthropometry. An experiment was performed to observe 15 subjects of three anthropometrical groups getting in and out of a car mock-up simulating three different vehicle configurations. Motor torques were extracted using an inverse dynamics analysis. Both ingress and egress motions were primarily characterised by large torques. Overall, the taller a subject and the lower the seat of the vehicle were, the larger the peak torques were. Moreover, peak torques were higher for egress than ingress. These results are discussed in regard to the current knowledge on I/E ergonomics. 相似文献
68.
69.
Jason Hochreiter Zhongkai HanSyed Zain Masood Spencer FonteMarshall Tappen 《Image and vision computing》2014
In this paper, we propose an album-oriented face-recognition model that exploits the album structure for face recognition in online social networks. Albums, usually associated with pictures of a small group of people at a certain event or occasion, provide vital information that can be used to effectively reduce the possible list of candidate labels. We show how this intuition can be formalized into a model that expresses a prior on how albums tend to have many pictures of a small number of people. We also show how it can be extended to include other information available in a social network. Using two real-world datasets independently drawn from Facebook, we show that this model is broadly applicable and can significantly improve recognition rates. 相似文献
70.
The paper presents a new approach for recommending suitable learning paths for different learners groups. Selection of the learning path is considered as recommendations to choosing and combining the sequences of learning objects (LOs) according to learners’ preferences. Learning path can be selected by applying artificial intelligence techniques, e.g. a swarm intelligence model. If we modify and/or change some LOs in the learning path, we should rearrange the alignment of new and old LOs and reallocate pheromones to achieve effective learning recommendations. To solve this problem, a new method based on the ant colony optimisation algorithm and adaptation of the solution to the changing optimum is proposed. A simulation process with a dynamic change of learning paths when new LOs are inserted was chosen to verify the method proposed. The paper contributes with the following new developments: (1) an approach of dynamic learning paths selection based on swarm intelligence, and (2) a modified ant colony optimisation algorithm for learning paths selection. The elaborated approach effectively assist learners by helping them to reach most suitable LOs according to their preferences, and tutors – by helping them to monitor, refine, and improve e-learning modules and courses according to the learners’ behaviour. 相似文献