982 resultados para DETERMINES


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随着FPGA的发展,FPGA测试技术也得到了很快地发展。因为FPGA的结构和传统专用集成电路有着本质的区别,在FPGA中不能形成可测性设计电路,但它的可编程能力决定了其测试电路可以通过编程的方法来实现。本文讨论了XilinxXC4000系列FPGA中互连资源的自动测试方法。提出了一种新的测试资源坐标定位方法,使得测试软件能够将测试配置转换成器件配置,并搭建了硬件测试平台,实现实体FPGA芯片测试。

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基于Stewart平台的六维力传感器具有结构紧凑、刚度大、量程宽等特点,它在工业机器人、空间站对接等领域具有广泛的应用前景。好的标定方法是正确使用传感器的基础。由于基于Stewart平台的六维力传感器是一个复杂的非线性系统,所以采用常规的线性标定方法必将带来较大的标定误差从而影响其使用性能。标定的实质是,由测量值空间到理论值空间的映射函数的确定过程。由函数逼近理论可知,当只在已知点集上给出函数值时,可用多项式或分段多项式等较简单函数逼近待定函数。基于上述思想,本文将整个测量空间划分为若干连续的子测量空间,再对每个子空间进行线性标定,从而提高了整个测量系统的标定精度。实验分析结果表明了该标定方法有效。

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本文给出了移动机器人的虚力导航和运动规划系统.这种方法结合最小方差估计算法(LM SE)能有效地对机器人进行实时导航和避撞.在预测过程中,根据导航的不同阶段和预测误差的变化情况,采用Fuzzy 规则动态地调整误差函数中的权重,使预测过程尽可能准确.导航算法的基本思想是首先通过预测算法来获得移动机器人的运动信息,然后虚力系统根据预测信息决定机器人的未来运动,仿真结果表明该方法实时性好,能准确躲避障碍物并且到达目标点

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提出一种采用附加测量机构直接测量并联机床运动平台位姿精度的方法。其基本思想是根据运动平台的运动特性在固定平台和运动平台之间增设附加测量机构,当运动平台运动时带动测量机构运动,通过安装在测量机构上的传感器测得广义坐标参量, 经运动学建模即可得到运动平台的位姿。当测量机构位姿正解求解速度满足实时控制要求时,利用该反馈信息对机床进行实时精度补偿和控制。基于上述思想建立的并联机床位姿测量系统可部分排除机床切削力变形和运动副间隙等误差, 从而提高机床的位姿测量精度。以一种五坐标并联机床为例,介绍采用附加测量机构直接测量运动平台位姿精度的建模方法。其中, 测量机构的综合十分重要。测量机构的组成决定了运动学模型的复杂程度, 即决定了运动学模型的计算效率。

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通过对Pal.King的模糊边缘检测算法进行改进,提出了一种快速模糊边缘检测算法。该快速算法不但简化了Pal.King算法中复杂的G和G-1运算,而且通过实验,确定了Tr变换中最佳的隶属度阈值,大大地减少了迭代次数。从实验结果中可以看出,该快速算法不但提高了Pal.King算法的效率,而且具有很强的检测模糊边缘和细小边缘的能力。这种快速算法的性能优越,是一种非常实用的、高效的的图像处理算法。

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This paper describes a method for limiting vibration in flexible systems by shaping the system inputs. Unlike most previous attempts at input shaping, this method does not require an extensive system model or lengthy numerical computation; only knowledge of the system natural frequency and damping ratio are required. The effectiveness of this method when there are errors in the system model is explored and quantified. An algorithm is presented which, given an upper bound on acceptable residual vibration amplitude, determines a shaping strategy that is insensitive to errors in the estimated natural frequency. A procedure for shaping inputs to systems with input constraints is outlined. The shaping method is evaluated by dynamic simulations and hardware experiments.

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Given n noisy observations g; of the same quantity f, it is common use to give an estimate of f by minimizing the function Eni=1(gi-f)2. From a statistical point of view this corresponds to computing the Maximum likelihood estimate, under the assumption of Gaussian noise. However, it is well known that this choice leads to results that are very sensitive to the presence of outliers in the data. For this reason it has been proposed to minimize the functions of the form Eni=1V(gi-f), where V is a function that increases less rapidly than the square. Several choices for V have been proposed and successfully used to obtain "robust" estimates. In this paper we show that, for a class of functions V, using these robust estimators corresponds to assuming that data are corrupted by Gaussian noise whose variance fluctuates according to some given probability distribution, that uniquely determines the shape of V.

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This report describes research about flow graphs - labeled, directed, acyclic graphs which abstract representations used in a variety of Artificial Intelligence applications. Flow graphs may be derived from flow grammars much as strings may be derived from string grammars; this derivation process forms a useful model for the stepwise refinement processes used in programming and other engineering domains. The central result of this report is a parsing algorithm for flow graphs. Given a flow grammar and a flow graph, the algorithm determines whether the grammar generates the graph and, if so, finds all possible derivations for it. The author has implemented the algorithm in LISP. The intent of this report is to make flow-graph parsing available as an analytic tool for researchers in Artificial Intelligence. The report explores the intuitions behind the parsing algorithm, contains numerous, extensive examples of its behavior, and provides some guidance for those who wish to customize the algorithm to their own uses.

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SIR is a computer system, programmed in the LISP language, which accepts information and answers questions expressed in a restricted form of English. This system demonstrates what can reasonably be called an ability to "understand" semantic information. SIR's semantic and deductive ability is based on the construction of an internal model, which uses word associations and property lists, for the relational information normally conveyed in conversational statements. A format-matching procedure extracts semantic content from English sentences. If an input sentence is declarative, the system adds appropriate information to the model. If an input sentence is a question, the system searches the model until it either finds the answer or determines why it cannot find the answer. In all cases SIR reports its conclusions. The system has some capacity to recognize exceptions to general rules, resolve certain semantic ambiguities, and modify its model structure in order to save computer memory space. Judging from its conversational ability, SIR, is a first step toward intelligent man-machine communication. The author proposes a next step by describing how to construct a more general system which is less complex and yet more powerful than SIR. This proposed system contains a generalized version of the SIR model, a formal logical system called SIR1, and a computer program for testing the truth of SIR1 statements with respect to the generalized model by using partial proof procedures in the predicate calculus. The thesis also describes the formal properties of SIR1 and how they relate to the logical structure of SIR.

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RESUMO: O controle de plantas voluntárias de soja (Glycine max ) é uma exigência estabelecida em lei. A criação do vazio sanitário determina o período na entressafra no qual não deve haver a presença no campo de plantas emergidas de soja. Essa deliberação visa reduzir o inóculo do fungo causador da ferrugem asiática da soja (Phakopsora pachyrhizi). Além disso, a competição imposta por essas plantas pode reduzir a produtividade das culturas em sucessão. O experimento foi conduzido a fim de avaliar o controle de plantas voluntárias de soja em cultivos de girassol (Helianthus annuus). Os tratamentos aplicados foram: testemunha capinada, testemunha sem capina, amônio glufosinato 40 g i.a. ha-1, amônio glufosinato 100 g i.a. ha-1, sulfentrazone 75 g i.a. ha-1, sulfentrazone 100 g i.a. ha-1, tembotrione 21 g i.a. ha-1, carfentrazone 4 g i.a. ha-1, saflufenacil 1,75 g i.a. ha-1, saflufenacil 3,5 g i.a. ha-1, triclopyr 120 g i.a. ha-1 e MSMA 197,5 g i.a. ha-1. O herbicida sulfentrazone nas doses de 75 e 100 g i.a. ha -1 causa fitotoxicidade ao girassol logo após a aplicação, porém há recuperação das plantas, sem prejuízo a produtividade da cultura. Esses mesmos tratamentos não causam morte total das plantas voluntárias de soja, mas paralisam temporariamente seu crescimento, evitando a competição com a cultura do girassol. O amônio glufosinato é eficaz no controle de plantas voluntárias de soja. No entanto, os sintomas de fitotoxicidade na cultura do girassol são elevados, refletindo em perda de rendimento da cultura. Os outros tratamentos não proporcionam controle satisfatório das plantas voluntárias de soja, além de causar redução na produtividade do girassol. ABSTRACT: The control of volunteer soybean (Glycine max) is regulated by law due to the host-free period which determines the interval that is not allowed the presence of soybean plants in fields. The decision aims to reduce the inoculum of the fungus that causes the Asian soybean rust (Phakopsora pachyrhizi). Furthermore, the competition imposed by volunteer soybean plants can reduce crop yields. The experiment was conducted to evaluate the control of volunteer soybean plants in sunflower (Helianthus annuus). The treatments were as follows: hoed check, check without hoeing, glufosinate ammonium 40 g ai ha-1, glufosinate ammonium 100 g ai ha-1, sulfentrazone 75 g ai ha-1, sulfentrazone 100 g ai ha-1, tembotrione 21 g ai ha-1, carfentrazone 4g ai ha-1, saflufenacil 1.75 g ai ha-1, saflufenacil 3.5 g ai ha -1, triclopyr 120 g ai ha-1 and MSMA 197.5 g ai ha-1. Sulfentrazone (75 and 100 g ai ha-1) caused phytotoxicity on sunflower plants, however there is recovery of plants and no yield losses. The same treatments do not cause the total death of volunteer soybean plants, however temporarily paralyze its growth and avoid competition with the sunflower crop. The glufosinate ammonium is effective in controlling volunteer soybean plants. However, symptoms of phytotoxicity in the sunflower crop are high, reflecting in yield losses. The other treatments do not provide satisfactory control of volunteer soybean plants and even cause reduction in sunflower productivity.

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McGuinness, T. and Morgan, R. (2005). The effect of market and learning orientation on strategy dynamics: The contributing effect of organisational change capability. European Journal of Marketing. 39(11-12), pp.1306-1326 RAE2008

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Los hábitos alimentarios de la juventud van cambiando y desarrollándose a lo largo del tiempo a causa de los patrones culturales y sociales que se establecen en el contexto. La adquisición de unos buenos hábitos es muy importante debido a que determina en gran medida nuestra salud y puede evitar la aparición de múltiples problemas sanitarios, entre los que encontramos la obesidad. Esta investigación trata de identificar, de acuerdo a la revisión bibliográfica, los factores que condicionan y definen el patrón alimentario de los y las jóvenes. En consecuencia, se han realizado cuestionarios a jóvenes de 15 y 16 años de Pamplona, durante un período de dos meses, con el fin de recabar información sobre las tendencias alimentarias en la muestra seleccionada para su posterior análisis.

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El estudio determina las características de la Economía Solidaria, desde la perspectiva de los movimientos sociales, en el marco del análisis de las auditorías de REASNavarra. Se contextualizan mediante revisión bibliográfica las características, tanto de la Economía Social y Solidaria (ESS) como de la Economía Social, y se contrasta con el caso particular de Navarra (España). Para el análisis de dichas auditorías se utilizó un enfoque metodológico longitudinal, resultando del mismo una “foto” representativa del comportamiento de las empresas de REAS-Navarra a lo largo de los años (2009, 2011 y 2013). El estudio concluye que REAS-Navarra, si bien cumple con criterios defendidos desde la Economía Solidaria, presenta debilidades en cuanto a la metodología utilizada para auditar sus empresas, y de los resultados del análisis de las auditorías sociales se desprenden dudas respecto al nivel de autonomía y democracia en estas empresas, lo que puede significar un riesgo para su continuidad.

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Piorunek Magdalena, Kasperek Ewa, Proces kształtowania się planów zawodowo- edukacyjnych młodzieży. Wyniki badań (The process of formation of professional and educational plans of young people - results of studies). „Neodidagmata” XX, Poznań 1991, Adam Mickiewicz University Press, pp. 101-112. ISBN 83-232-0302-4. ISSN 0077-653X. Received: October 1988. Studies were conducted on the formation of professional and educational plans of young people in the primary school. It was found that the period of specific search for professional and educational careers of young people is preceded by an initial elimination of the definite ways of education (types of school) which determines further decisions of various stages of education of adolescents. The eighth class (form) is the the stage of most intensive searching as far as professions and education are concerned and their characteristic feature is great variability. The liability of professional-educational plans is decisively greater in young people from large cities.

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Wydział Neofilologia: Instytut Filologii Romańskiej