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地滚式手动喷雾器
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《农业开发与装备》 1996年第6期53-53,共1页
该产品主要用于烟、叶、蔬菜等旱地的一种人工植保机械,其结构特点: 1.以药液箱为地轮,气室及柱塞泵装入药液箱内,人工推动药液箱滚动前进,带动柱塞泵端偏心凸轮实现柱塞泵中的塞杆作往复运动,完成边行走边喷雾作业。 2.无需人工背负药... 该产品主要用于烟、叶、蔬菜等旱地的一种人工植保机械,其结构特点: 1.以药液箱为地轮,气室及柱塞泵装入药液箱内,人工推动药液箱滚动前进,带动柱塞泵端偏心凸轮实现柱塞泵中的塞杆作往复运动,完成边行走边喷雾作业。 2.无需人工背负药液箱工作,省去了人工手摇摇杆,减轻了劳动强度。 展开更多
关键词 柱塞泵 药液箱 人工推动 偏心凸轮 植保机械 结构特点 滚式 往复运动 农业机械化 劳动强度
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Analog circuit intelligent fault diagnosis based on GKPCA and multi-class SVM approach 被引量:2
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作者 伞冶 郭珂 朱奕 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2012年第6期63-71,共9页
Analog circuits fault diagnosis is essential for guaranteeing the reliability and maintainability of electronic systems. In this paper, a novel analog circuit fault diagnosis approach is proposed based on greedy kerne... Analog circuits fault diagnosis is essential for guaranteeing the reliability and maintainability of electronic systems. In this paper, a novel analog circuit fault diagnosis approach is proposed based on greedy kernel principal component analysis (KPCA) and one-against-all support vector machine (OAASVM). In order to obtain a successful SVM-based fault classifier, eliminating noise and extracting fault features are very important. Due to the better performance of nonlinear fault features extraction and noise elimination as compared with PCA, KPCA is adopted in the proposed approach. However, when we adopt KPCA to extract fault features of analog circuit, a drawback of KPCA is that the storage required for the kernel matrix grows quadratically, and the computational cost for eigenvector of the kernel matrix grows linearly with the number of training samples. Therefore, GKPCA, which can approximate KPCA with small representation error, is introduced to enhance computational efficiency. Based on the statistical learning theory and the empirical risk minimization principle, SVM has advantages of better classification accuracy and generalization performance. The extracted fault features are then used as the inputs of OAASVM to solve fault diagnosis problem. The effectiveness of the proposed approach is verified by the experimental results. 展开更多
关键词 greedy kernel principal component analysis one-against-all support vector machine fault diagno- sis analog circuit
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Reproducing wavelet kernel method in nonlinear system identification
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作者 文香军 许晓鸣 蔡云泽 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2008年第2期248-254,共7页
By combining the wavelet decomposition with kernel method, a practical approach of universal multiscale wavelet kernels constructed in reproducing kernel Hilbert space (RKHS) is discussed, and an identification sche... By combining the wavelet decomposition with kernel method, a practical approach of universal multiscale wavelet kernels constructed in reproducing kernel Hilbert space (RKHS) is discussed, and an identification scheme using wavelet support vector machines (WSVM) estimator is proposed for nordinear dynamic systems. The good approximating properties of wavelet kernel function enhance the generalization ability of the proposed method, and the comparison of some numerical experimental results between the novel approach and some existing methods is encouraging. 展开更多
关键词 wavelet kernels support vector machine (SVM) reproducing kernel Hilbert space (RKHS) nonlinear system identification
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Ship spare parts demand forecast based on RBF neural network
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作者 盖强 刘勇 赵宏宇 《Journal of Measurement Science and Instrumentation》 CAS 2013年第2期167-169,共3页
Due to the fact that in ship maintena n ce process,the method of determining the number of spare parts is not scientific and the actual operation is complicated,this paper analyzes four major facto rs affecting the nu... Due to the fact that in ship maintena n ce process,the method of determining the number of spare parts is not scientific and the actual operation is complicated,this paper analyzes four major facto rs affecting the number of ship spare parts,including number of main planned op eration s,total times of disassembling in maintenance,accumulated working time and mea n t ime between failures.It also establishes a spare parts demand forecast model b ased on the affecting factors and radial-basis function(RBF) neural network.F inally,the paper provide s forecast examples and makes a comparison between the examples and back propaga tion(BP) neura l network forecast result.The comparison results s how that the forecast based on RBF neural network is simple and the forecast res ult fits the actual situa tion and fitting effect is better than that based on BP. 展开更多
关键词 spare parts forecast neural network equipment support
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在巴音布鲁克牧区有效利用草场资源提高草场有效利用率的探讨
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作者 帕提古丽·托乎提 《今日畜牧兽医》 2022年第8期72-73,75,共3页
草原是和静县面积最大的生态系统和自然资源,是推进生态文明建设的主要阵地,对维护国家生态安全、促进经济社会发展具有重要作用。几年来,巴音布鲁克草原生态明显恢复,巴音布鲁克草原生态环境得到了改善。巴音布鲁克镇、巴音郭楞乡、巩... 草原是和静县面积最大的生态系统和自然资源,是推进生态文明建设的主要阵地,对维护国家生态安全、促进经济社会发展具有重要作用。几年来,巴音布鲁克草原生态明显恢复,巴音布鲁克草原生态环境得到了改善。巴音布鲁克镇、巴音郭楞乡、巩乃斯镇、巴音布鲁克牧场、德尔布力金牧场、伊克扎尕斯台牧场草场等草场资源丰富,养殖的牲畜数量较多,这对巴音布鲁克地区草场资源的保护带来一定的压力。为了合理利用草场资源,实施禁牧及草畜平衡,实施草原生态补奖政策,优化畜群结构,加快农区畜牧业发展,推动人工饲草基地建设等措施,鼓励和引导牧民在农区接育冬羔和早春羔,推广农区标准化养殖、合作社入股经营。特别是冬季牧民下山,在农区集中养殖或在农区耕地过冬或建立牧民专业合作社等方式冬季牲畜下山养殖,提高羊羔成活率,实现“草原绿、牲畜稳、产业强、牧民富”的目标。 展开更多
关键词 禁牧及草畜平衡 草原生态补奖政策 优化畜群结构 推动人工饲草基地建设
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A Bandit Method Using Probabilistic Matrix Factorization in Recommendation
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作者 涂世涛 朱兰娟 《Journal of Shanghai Jiaotong university(Science)》 EI 2015年第5期535-539,共5页
In recommendation system,sparse data and cold-start user have always been a challenging problem.Using a linear upper confidence bound(UCB) bandit approach as the item selection strategy based on the user historical ra... In recommendation system,sparse data and cold-start user have always been a challenging problem.Using a linear upper confidence bound(UCB) bandit approach as the item selection strategy based on the user historical ratings and user-item context,we model the recommendation problem as a multi-arm bandit(MAB)problem in this paper.Enabling the engine to recommend while it learns,we adopt probabilistic matrix factorization(PMF) in this strategy learning phase after observing the payoff.In particular,we propose a new approach to get the upper bound statistics out of latent feature matrix.In the experiment,we use two public datasets(Netfilx and MovieLens) to evaluate our proposed model.The model shows good results especially on cold-start users. 展开更多
关键词 recommend matrix factorization bandit
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