909 resultados para GA-FACE
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以模糊推理和遗传算法为基础,提出了一种新的具有不完全微分的最优PID控制器的设计方法,该控制器由离线和在线两部分组成,在离线部分,以系统响应的超调量、上升时间以及调整时间为性能指标,利用遗传算法搜索出一组最优的PID参数Kp^*、Ti^*和Td^*,作为在线部分调整的初始值,在在线部分,一个专用的PID参数优化程序以离线部分获得Kp^*、Ti^*和Td^*为基础,根据系统当前的误差e和误差变化率e^.,通过一个模糊推理系统在线调整系统瞬态响应的PID参数,以确保系统的响应具有最优的动态和稳态性能.该控制器已被用来控制由作者设计的智能仿生人工腿中的执行电机.计算机仿真结果表明,该控制器具有良好的控制性能和鲁棒性能。
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研究资源受限系统动态调度问题,针对时序约束问题提出一种并行遗传算法(PGA)。给出满足排序优先次序约束的一种基因编码方法;采用不破坏优先级可行性的交叉操作,并予以证明;建立一种并行处理机制,使搜索避免出现局优现象。在技术允许情况下,单机动态调度引入抢占式加工方式,会一定程度上提高系统的性能。通过仿真试验验证,并行GA算法可兼顾优化效果和计算效率,解决单机动态调度问题。
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独立分量分析是一种有效的人脸特征提取方法。考虑到人脸样本的对称性,本文采用对称独立分量分析的方法对人脸样本进行特征提取。为了提高独立分量分析法表征人脸特征空间的能力,本文采用遗传算法对特征空间进行选择优化,获得最优的人脸特征子集。仿真实验表明,本文提出方法的识别率明显的好于独立分量分析方法的识别率。
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扬子地块西南缘分布着大量富含Cd、Ge与Ga的铅锌矿床,已成为我国Pb、Zn及Cd、Ge与Ga矿产资源的重要生产基地。对代表性铅锌矿床进行野外地质调查和系统采样鉴定后.应用电子探针微区分析手段,研究主要矿石矿物闪锌矿、方铅矿和黄铁矿中分散元素的富集特征。结果显示.各类矿床中闪锌矿均相对富集Cd,方铅矿富集Ge与Ga,而黄铁矿中Cd、Ge与Ga的富集系数均相对较低.未呈现出选择性富集的趋势;赋存于震旦纪一寒武纪地层且以脉状、网脉状产出的矿体中闪锌矿的Cd含量明显高于赋存于晚古生代并以层状产出的矿体中闪锌矿的Cd含量。
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While researchers in computer vision and pattern recognition have worked on automatic techniques for recognizing faces for the last 20 years, most systems specialize on frontal views of the face. We present a face recognizer that works under varying pose, the difficult part of which is to handle face rotations in depth. Building on successful template-based systems, our basic approach is to represent faces with templates from multiple model views that cover different poses from the viewing sphere. Our system has achieved a recognition rate of 98% on a data base of 62 people containing 10 testing and 15 modelling views per person.
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In this paper three problems related to the analysis of facial images are addressed: the illuminant direction, the compensation of illumination effects and, finally, the recovery of the pose of the face, restricted to in-depth rotations. The solutions proposed for these problems rely on the use of computer graphics techniques to provide images of faces under different illumination and pose, starting from a database of frontal views under frontal illumination.
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If we are provided a face database with only one example view per person, is it possible to recognize new views of them under a variety of different poses, especially views rotated in depth from the original example view? We investigate using prior knowledge about faces plus each single example view to generate virtual views of each person, or views of the face as seen from different poses. Prior knowledge of faces is represented in an example-based way, using 2D views of a prototype face seen rotating in depth. The synthesized virtual views are evaluated as example views in a view-based approach to pose-invariant face recognition. They are shown to improve the recognition rate over the scenario where only the single real view is used.
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The correspondence problem in computer vision is basically a matching task between two or more sets of features. In this paper, we introduce a vectorized image representation, which is a feature-based representation where correspondence has been established with respect to a reference image. This representation has two components: (1) shape, or (x, y) feature locations, and (2) texture, defined as the image grey levels mapped onto the standard reference image. This paper explores an automatic technique for "vectorizing" face images. Our face vectorizer alternates back and forth between computation steps for shape and texture, and a key idea is to structure the two computations so that each one uses the output of the other. A hierarchical coarse-to-fine implementation is discussed, and applications are presented to the problems of facial feature detection and registration of two arbitrary faces.
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The problem of automatic face recognition is to visually identify a person in an input image. This task is performed by matching the input face against the faces of known people in a database of faces. Most existing work in face recognition has limited the scope of the problem, however, by dealing primarily with frontal views, neutral expressions, and fixed lighting conditions. To help generalize existing face recognition systems, we look at the problem of recognizing faces under a range of viewpoints. In particular, we consider two cases of this problem: (i) many example views are available of each person, and (ii) only one view is available per person, perhaps a driver's license or passport photograph. Ideally, we would like to address these two cases using a simple view-based approach, where a person is represented in the database by using a number of views on the viewing sphere. While the view-based approach is consistent with case (i), for case (ii) we need to augment the single real view of each person with synthetic views from other viewpoints, views we call 'virtual views'. Virtual views are generated using prior knowledge of face rotation, knowledge that is 'learned' from images of prototype faces. This prior knowledge is used to effectively rotate in depth the single real view available of each person. In this thesis, I present the view-based face recognizer, techniques for synthesizing virtual views, and experimental results using real and virtual views in the recognizer.
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The setting, marking and providing feedback on assessments forms an important part of a tutor’s role. Studies into the use of feedback and how it is interpreted by students indicate a mismatch between what students are looking for and what tutors think they are giving. Tutors comment that students are more interested in the mark than the feedback, and yet students indicate that they do not get enough feedback, or that it is not useful. This study investigates student and staff perceptions of the linking of marking and feedback in face-to-face sessions. A cohort of year one university students were given the option of receiving either written feedback or a 15 minute meeting with one of their tutors to have their essay marked with them. Forty nine students chose face-to-face marking, the remaining 35 students received written feedback. Focus groups were used to investigate the student experience. Staff members were also asked to reflect on the process. Students and staff found the experience of face-to-face marking beneficial and positive. Both felt that the time spent together allowed for a feedback dialogue about the piece of work, and that staff could explain and justify why marks were given.
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Jasimuddin, Sajjad, Klein, Jonathan, and Connell, Con, 'The paradox of using tacit and explicit knowledge: Strategies to face dilemnas', Management Decision (2005) 43(1) pp.102-112 RAE2008
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Wydział Filologii Polskiej i Klasycznej: Instytut Filologii Polskiej
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Oculographical research of people watching a human face indicates than beholder's eyes stop most often and for the longest period of time on the eyes and the mouth of the face looked at and that they move among these three points most frequently. The position of the eyes and mouth in relation to one another can be described with a single number being a measure of an angle with the vertex in the middle of the mouth and with arms crossing the centers of the eye pupils. The angles were measured from photographs of people from all over the world, as well as of residents of Lublin. Subsequently, the subjects from Lublin were asked to make face schemas by positioning the eyes and the mouth in the way they considered most attractive. The eye-mouth-eye angle of these schemas was measured. Additionally, measurements of the same angle were taken from the faces depicted in icons. The schemas of the most attractive - according to the subjects - faces were characterized by angles approximating the mean angle from the photographs, and significantly greater than the mean angle from the icons.
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Dissertação apresentada à Universidade Fernando Pessoa como parte dos requisitos para obtenção do grau de Mestre em Mestre em Psicologia especialização em Psicologia da Saúde e Intervenção Comunitária.