Results 51 to 60 of about 17,163 (167)
Dianci bileiqi, 2020 为解决500 kV瓷绝缘子串红外图像分割问题,提出了一种基于分水岭算法的图像分割方法。通过调整红外图像G分量消除云雾干扰,图像预处理后采用灰度拉伸法进行图像增强;然后利用Otsu算法将灰度图像二值化,通过Hough变换确定绝缘子串基准线,并据此使用Floodfill算法提取绝缘子串目标区域;角度校正后做欧式距离变换,以局部最小值为标记符避免过分割,再采用分水岭算法进行绝缘子片分割。据此对湖南省某座500 kV变电站700张红外图像进行分析,结果表明,本文所提方法具有良好的自适应性和实用性 ...
刘正庭 +6 more
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Pure ti-based mixed oxides prepared from the thermal decompositions of molecular precursors of peroxo complexes coordinated with tris(hydroxycarbonylmethyl)amine trivalent anion titanate(IV) [PDF]
, 2004 Different peroxo titanate (IV) complexes coordinated with tris(hydroxycarbonylmethyl) amine trivalent anion including ammonium, potassium, strontium and barium salts (NH4)(4)[Ti2O(O-2)(2)(ta)(2)]-4H(2)0 (1), K-4[Ti2O(O-2)(2)(ta)(2)]-6H(2)O (2), Sr-2[Ti2O(
DENG, Yuan-Fu +5 more
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Poverty &Public Policy, Volume 17, Issue 4, December 2025.ABSTRACT With most unemployed youth residing in rural areas of South Africa, incentivising youth participation in smallholder farming can help address the increasing youth unemployment crisis. The study integrated the theory of planned behavior and the sustainable livelihood framework to investigate the factors influencing rural youth participation in ...
Humbulani Portia Rambuda +2 more
wiley +1 more source
Gaoya dianqi, 2009 考虑到磁性材料的非线性特点,在计算磁路时往往比较复杂。目前求解磁路的主要方法有:解析法、图解法、数值计算法。针对永磁机构设计中提出的问题,建立了分段法分析铁心磁路的模型,结合Office Excel中的曲线拟合功能,利用图示法快速直观的求解磁路。得出了永磁机构铁心各部分的尺寸和磁场状态,为永磁机构磁路设计提供了依据。实验结果表明,利用此种方法不仅简化了求解过程,大大的加快了求解速度,而且可以直观的反应求解过程,便于进一步分析和优化磁路。
冯英, 武建文, 秦晨
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基于Surfacelet 变换的3D Context 模型视频去噪新方法 [PDF]
, 2008 本文将3D Context 模型应用于Surfacelet 变换域,提出一种新的视频去噪方法. Surfacelet 变换(ST) 是一种新的3D 变换,具有多方向分解、各向异性和低冗余度等性质. 根据视频信号ST 域内系数和噪声分布的特征,将2D Context 模型拓展到3D ,按照能量分布将ST系数分成多个子块,每个子块有独立的能量和阈值估计. 实验结果表明,本文算法噪声抑制效果明显优于分层2D 去噪声方法和其它现有的3D 方法,去噪视频的PSNR 值提高了约2dB.
屈小波, 肖弘智, 闫敬文
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Evaluating protected areas’ coverage of threats to terrestrial biodiversity
Conservation Biology, Volume 39, Issue 6, December 2025.Abstract Protected areas (PAs) are vital for biodiversity conservation and have expanded globally. However, increasing pressures on biodiversity make it difficult to achieve conservation goals. Using threat probability maps based on the International Union for Conservation of Nature Red List and the World Database of Protected Areas, we analyzed the ...
Katherine Pulido‐Chadid +2 more
wiley +1 more source
Jixie chuandong, 1991 当组成复合轮系的简单行星轮系的个数较多时,复合轮系的运动分析就非常繁杂。本文提出一种研究复合行星轮系运动的图解法,利用简单的线图即可求出其中任一基本构件的运动,不必作辅助计算。根据线图上的几何关系,还可迅速写出传动比的准确计算公式,比之用分析计算法来推导要简便快捷得多。除了一个自由度的复合轮系外,本图解法还可解决多个自由度的复合行星轮系的问题。
何廷樾
doaj
Pure Ti-based Mixed Oxides Prepared from the Thermal Decompositions of Molecular Precursors of Peroxo Complexes Coordinated with Tris(hydroxycarbonylmethyl)amine Trivalent Anion Titanate(Ⅳ) [PDF]
, 2004 在pH =2 5～ 4 0的条件下 ,以四氯化钛、过氧化氢和氨三乙酸为原料反应得到四种过氧酸钛配合物 (NH4) 4 [Ti2 O (O2 ) 2 (ta) 2 ]·4H2 O (1) ,K4[Ti2 O(O2 ) 2 (ta) 2 ]·6H2 O (2 ) ,Sr2 [Ti2 O(O2 ) 2 (ta) 2 ]·10H2 O (3 )和Ba2 [Ti2 O(O2 ) 2 (ta) 2 ]·10H2 O (4 )(H3 ta =C6H6O6N) .配合物的EA ,UV vis ...
周朝晖, 洪麒明, 邓远富
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Conservation Biology, Volume 39, Issue 6, December 2025.Abstract As the coverage of area‐based conservation increases across the globe, it is critical to improve understanding of the social and ecological outcomes of such measures and the pathways to their outcomes. A social–ecological systems approach to monitoring and evaluation is increasingly advocated; yet, applications remain scarce.
Natalie C. Ban +21 more
wiley +1 more source
, 2018 为更加准确识别某中型客车怠速工况下的方向盘振动来源,提升传递路径分析精度,文中总结了基于悬置刚度法分析振动传递路径的基本方法,并以该车方向盘为研究对象开展方法验证。首先,通过计算该车悬置软垫预载力、对已有的悬置软垫数据进行多元回归拟合以及整车方向动刚度转化计算出该悬置软垫实际动刚度;其次,测试系统水平频响函数以及激励点与响应点的加速度信号;再次,用基于阻抗矩阵法TPA所得的结果以及实测结果作为标杆进行对比,比较结果显示悬置刚度法TPA具有较高的精度 ...
侯亮 +4 more
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