920 resultados para Planing-machines.


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Studies on learning problems from geometry perspective have attracted an ever increasing attention in machine learning, leaded by achievements on information geometry. This paper proposes a different geometrical learning from the perspective of high-dimensional descriptive geometry. Geometrical properties of high-dimensional structures underlying a set of samples are learned via successive projections from the higher dimension to the lower dimension until two-dimensional Euclidean plane, under guidance of the established properties and theorems in high-dimensional descriptive geometry. Specifically, we introduce a hyper sausage like geometry shape for learning samples and provides a geometrical learning algorithm for specifying the hyper sausage shapes, which is then applied to biomimetic pattern recognition. Experimental results are presented to show that the proposed approach outperforms three types of support vector machines with either a three degree polynomial kernel or a radial basis function kernel, especially in the cases of high-dimensional samples of a finite size. (c) 2005 Elsevier B.V. All rights reserved.

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目前支持向量机解决模式识别问题是广大学者研究的热点,样本的后验概率在模式识别中至关重要,但是传统的支持向量机技术不提供后验概率.针对这一问题进行了3个方面的研究:①在给出样本点后验概率的基础上,将大规模优化问题分解成最大似然函数和最大分类边界两个小规模优化问题;②给出了一种新的用后验概率修正最优分离超平面的方法,并且分析了该新方法的合理性;③用图像分类的3组实例说明本方法的有效性.

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Marine animals and micro-machines often use wiggling motion to generate thrust. The wiggling motion can be modeled by a progressive wave where its wavelength describes the flexibility of wiggling animals. In the present study, an immersed boundary method is used to simulate the flows around the wiggling hydrofoil NACA 65-010 at low Reynolds numbers. One can find from the numerical simulations that the thrust generation is largely determined by the wavelength. The thrust coefficients decrease with the increasing wavelength while the propulsive efficiency reaches a maximum at a certain wavelength due to the viscous effects. The thrust generation is associated with two different flow patterns in the wake: the well-known reversed Karman vortex streets and the vortex dipoles. Both are jet-type flows where the thrust coefficients associated with the reversed Karman vortex streets are larger than the ones associated with the vortex diploes.

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土地利用是人类根据土地质量特性来开发利用土地,创造财富,满足人类生产和生活的需要,同时改善环境,满足人类生存需要的过程。土地利用总体规划是对未来各类用地在空间上、时间上作出总体的协调的预先安排,不仅受到一定历史背景的制约,同时也受影响于当前的社会经济发展情况。但是,国内传统的土地利用总体规划往往从狭窄的技术经济观点出发,对远期的生态环境问题、社会问题缺少考虑,将新的用地尽量安排在最便捷、最经济的地方。 由于土地利用总体规划对环境影响具有长期性、复杂性、综合性、有时还有不可逆转性等特点,迫切需要在编制土地利用总体规划时对规划区与土地利用有关的环境影响进行科学研究,把环境保护纳入土地利用活动的计划、决策和规划实施中,促进土地资源持续、协调的利用。为更好地进行土地利用总体规划环境影响评价必须首先建立相应的评价指标体系,而目前国内关于该项研究的理论和实践的相关报道都较少。 本论文在综述国内外土地利用总体规划环境影响评价的理论与实践的基础上,在国内第一批开展了相关领域的案例研究,采用理论研究和案例分析相结合的研究方法对土地利用总体规划环境影响评价方法和指标体系进行了研究,对邛崃市土地利用总体规划进行了环境影响评价,其研究的主要内容和论点如下: (1)第一次根据FAO 确定的五大原则,引入了生态用地的概念并按照价值模型构建了以土地资源可持续利用为目标的县级土地利用总体规划环境影响评价的指标体系。以生产性、稳定性、保护性、经济活力、社会可接受性五个方面作为指标层来度量土地利用总体规划的环境影响,并选取了土地利用率、土地整理率、水面指数、生态用地面积比例、耕地转化率、建设用地产值指数、公众满意度等21 个元指标作为具体的评价指标。该指标体系强调了规划方案的公众参与,便于充分吸收公众的意见和建议;并且评价指标获取容易,实用性较强。 (2)在土地利用总体规划环境影响评价方法上进行了有益的探索和尝试,由于土地利用总体规划环境影响评价的主要对象是几个拟定的规划方案,所以采用综合评分法(包括特尔斐法和层次分析法)和公众参与相结合的评价方法。应用上述指标体系和评价方法对邛崃市土地利用总体规划的三个方案进行了评价筛选,高方案最终得分为92.049;中方案最终得分为91.028;而低方案最终得分为95.541,为最优方案。 (3)开展了对土地利用总体规划替代方案和公众参与机制的研究,对公众参与的方式、程序及主要内容从理论和实践两方面进行了有益的尝试,收到了良好的效果。 (4)对邛崃市土地利用总体规划进行了环境影响评价,根据邛崃市的具体情况,对规划实施后可能造成的环境正、负面影响进行了分析和预测,提出了预防或者减轻不良环境影响的对策和措施。 Land use is a process, which is to develop land according to its mass property. Bycreating the wealth and improving the environment, it can meet the need of production,life and human survival. Land use planning, as a planning form to guide land use, issubject to the historical background, and influenced by development of economic andsociety. The land use planning in the past, from narrow economic technology view,lacking of concerning ecologic environmentand social problem, arranged new land in the most convenient and economic place. Because of complexity, comprehensive and sometimes irreversible characteristicsof environmental impact caused by land use planning which has been implemented, it isneed to carry on scientific research on environmental impact related to land use as theland use planning is forming, to bring environmental protection within the plan, policymaking and implementing of land use activity, promoting the sustainment, harmonious use of land resource. This paper, taking the readjustment of land use planning in Qionglai as an example,assessed its environmental impact of land use planning. The main contents and results arepresented as follows: (1) On the basis of the five criterions of AFO, for the first time propose county classoverall planning of land uses SEA index by inducting ecological land use andestablishing the Value factor system, according to Productivity criterion,Stabilitycriterion,Sheltered criterion,Economic livingness criterion,Social acceptabilitycriterion,the environmental impact of land use system was assessed by using Valuemodel. Through identifying the factors of environmental impact of land use planning, thepaper established the factor system of SEA of land use planning. From the land usefactors, 21 factors was chosen to assess the environmental impact degree of land useplanning, such as, index of land use degree, the rate of land collating, index of watersurface, the rate of ecological use land, cultivated land conversion ratio, forest landconversion ratio, public satisfaction degree and so on. These indexes make a point thatpublic participation of plan project fully absorb public idea and propose and the index easily get, better utility. (2) Attempt useful assessment method system of SEA of land use planning. In viewof there are no or almost no inevitable contact among the factors of SEA of land useplanning,we use AHP (Analytic Hierarchy Process) as the main assess method . Thereare three plans are compared in this paper apply the foregoing index and assessmentmethod. The high plan finally score is 92.049,while the middle plan is 91.028. The lowplan score is 95.541,is the best one,as the selected plan. (3) Carry on the research of the alternative scheme of overall planing of land useand public participation,to the fashion ,procedure and object matter carry out helpfulattempt from theory to practice,the results is good. (4)Took place SEA of Qionglai County overall planing of land use,according to thecircumstance of Qionglai,we analyze and forecast the positive and negative affect afterthe plan implement,and put forward the countermeasure and means to prevent or abatebad environmental impact.

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论述用于兰州重离子加速器冷却存储环(HIRFL-CSR)磁铁电源控制系统的数字控制系统硬件平台设计。该系统基于1mmBGA封装的ALTER corporation的cycloneⅢFPGA芯片,嵌入运行数字调节器软件算法,满足了针对具体被控对象参数要求的调节控制。用ARM(Advanced RISC Machines)作调节控制系统的核心处理器,完成系统的多线程任务处理;同时嵌入千兆光纤接口,实现外接DSP板处理数据的直接传输,提高了系统的实时性。该硬件平台实现了HIRFL-CSR电源系统的稳定、可靠和实时控制。

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区域水土流失评价对于水土流失区域治理的宏观决策、规划等具有十分重要的意义 .本文以黄土高原地区为例 ,结合影响水土流失的各个因子 ,分析了该区的自然特征 ,确定了进行区域水土流失评价的各项指标 (模型参数 ) ,并运用 GIS,集成了多种来源、多种比尺和多种类型的数据 ,建立了该区的水土流失宏观定量评价模型

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Univ SE Calif, Ctr Syst & Software Engn, ABB, Microsoft Res, IEEE, ACMSIGSOFT, N Carolina State Univ Comp Sci

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The Gaussian process latent variable model (GP-LVM) has been identified to be an effective probabilistic approach for dimensionality reduction because it can obtain a low-dimensional manifold of a data set in an unsupervised fashion. Consequently, the GP-LVM is insufficient for supervised learning tasks (e. g., classification and regression) because it ignores the class label information for dimensionality reduction. In this paper, a supervised GP-LVM is developed for supervised learning tasks, and the maximum a posteriori algorithm is introduced to estimate positions of all samples in the latent variable space. We present experimental evidences suggesting that the supervised GP-LVM is able to use the class label information effectively, and thus, it outperforms the GP-LVM and the discriminative extension of the GP-LVM consistently. The comparison with some supervised classification methods, such as Gaussian process classification and support vector machines, is also given to illustrate the advantage of the proposed method.

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A simple and rapid colorimetric pH meter has been developed based on the conformational switch of i-motif DNA and non-crosslinking AuNP aggregation, the average accuracy of the nano-meter was found to be +/- 0.04 pH unit across the physiological operating range.

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提出一种新型并联机器人机构 ,利用张紧柔索驱动该并联机器人·通过运动学和动力学分析、工作空间分析、轨迹规划、误差分析 ,设计并制作了模型样机本体、驱动与控制模块 ,开发了机器人语言 ,控制模型样机完成指定动作·实验结果表明 ,这种新型并联机器人是可行的 ,适用于轻型机床等设备·该机器人在某一速度范围内工作时 ,会产生较明显的振动 ,并伴有噪声 ,因此要提高机器人的性能还必须设法抑制其振动

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机器人化是提高工程机械施工控制自动化的关键问题。对于工程机械机器人 ,特别是具有空间冗余度的工程机械机器人 ,其执行机构末端的轨迹规划的自动实现研究对提高其自动化程度有着重要意义。本文以泵车为例 ,提出了一种泵车布料机构的浇筑过程的自动轨迹规划算法 ,该算法通过将其所浇筑区域离散成浇筑点集 ,对两浇筑点的轨迹利用冗余度机器人学的最小关节范数法 ,并通过在关节速度和加速度非连续之处采用平滑或连续处理 ,从而实现了泵车布料机构浇筑过程的自动轨迹规划。

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以5坐标并联机床为依托,面向不同构型并联机床,采用“PMAC+IPC”双CPU为硬件平台、VisualC++6.0为软件平台,开发了基于Windows操作平台的开放式并联机床数控系统。本文介绍了本数控系统的硬件结构、软件构成,并对数控软件开发的关键技术进行了阐述。

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许多工程机械的工作装置属于冗余度机器人的范畴 ,该类机械施工控制自动化所涉及到的轨迹规划问题 ,一直受到人们的重视·采用冗余度机器人运动学的最小关节力矩法 ,对空间4R冗余度机器人的关节轨迹的运动规划进行了分析仿真·实验表明该方法实际可行 ,运动学和动力学的工作特性良好·

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机器人化是提高工程机械施工控制自动化的关键问题·通过将泵车布料机构的浇筑区域离散为浇筑点集 ,对两浇筑点内轨迹利用冗余度机器人学的最小关节范数法的轨迹规划 ,并将两相临浇筑段自动连接和自动协调 ,从而实现了混凝土泵车布料机构浇筑过程自动轨迹规划·