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浅谈吉林省粮食主产区农户经济行为
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作者 王大彬 王学明 +1 位作者 邱恩义 孔祥智 《技术经济》 1999年第2期27-29,共3页
关键词 农户经济行 粮食主产区 吉林省 农户投资 粮食生产 农户消费 生产性固定资产 投工量 投资行为 劳动力
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日本果树业展望
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作者 宋树恢 《世界农业》 1987年第12期53-53,共1页
日本进行大规模商业性水果生产的起步比欧美都迟,但发展迅速,现已成为日本农业中的重要支柱之一。 日本果树业有三大特点:(1)多劳动密集型小面积果园。日本75%的果园在半公顷以下,一公顷以上的果园不足10%。每公顷果园年投工量在3000... 日本进行大规模商业性水果生产的起步比欧美都迟,但发展迅速,现已成为日本农业中的重要支柱之一。 日本果树业有三大特点:(1)多劳动密集型小面积果园。日本75%的果园在半公顷以下,一公顷以上的果园不足10%。每公顷果园年投工量在3000小时以上,大大高于西欧的指标。(2)直接消费鲜果,加工水果的比例很小,仅占总产量的27%。(3)水果价格季节性摆动大。 展开更多
关键词 果树业 日本农业 控制方法 果树科研机构 果园 水果生产 劳动密集型 热带水果 投工量 技术措施
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确保山中土 永葆山常青
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作者 张水津 《国土绿化》 2002年第1期32-32,共1页
从60年代以来,南方山地,采伐迹地更新造林基本上都是采用传统的炼山,不仅造成严重的水土流失,而且造成山地土质退化,栽种的树越种越小,成材很慢。早在60年代,国家林业局就提倡不炼山造林,但人们认为不炼山造林投工量较大,树木生长也较慢... 从60年代以来,南方山地,采伐迹地更新造林基本上都是采用传统的炼山,不仅造成严重的水土流失,而且造成山地土质退化,栽种的树越种越小,成材很慢。早在60年代,国家林业局就提倡不炼山造林,但人们认为不炼山造林投工量较大,树木生长也较慢,不炼山更新造林的方法难以推广。 展开更多
关键词 更新造林 树木生长 阔叶树 采伐迹地 南方山地 杉木 60年代以来 人们认为 国家林业局 投工量
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垄作二铧犁上安装除草部件好
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作者 潘巍 单景泉 《农业开发与装备》 1999年第3期17-17,共1页
中耕除草作业约占农作物总投工量的30%~50%。在垄作二铧犁上安装垄帮除草部件(俗称夹犁)可以解决中耕除草时的时间紧、用工量多、劳动强度大、劳力紧张的矛盾。
关键词 中耕除草作业 动强度 农作物 黑龙江省龙江县 投工量 结构原理 用工 松土效果 伸缩套管 固定联结
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Research and development of fringe projection-based methods in 3D shape reconstruction 被引量:13
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作者 WU Lu-shen PENG Qing-jin 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2006年第6期1026-1036,共11页
This paper discusses current research and development of fringe projection-based techniques. A system based on Fourier transform profilometry (FTP) is proposed for three-dimensional (3D) shape recovery. The system imp... This paper discusses current research and development of fringe projection-based techniques. A system based on Fourier transform profilometry (FTP) is proposed for three-dimensional (3D) shape recovery. The system improves the method of phase unwrapping to gain accurate 3D shapes of objects. The method uses a region-growing algorithm for the path prediction guided by the quality map to increase the recovering accuracy and provides a fast and simple tool for 3D shape recovery. The shape measurement and data recovery are integrated to offer a new method of 3D modelling. Examples are presented to verify the feasibility of the proposed method. 展开更多
关键词 3D modelling Fringe projection Quality map 3D measurement Reverse engineering
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Application in soft sensing modeling of chemical process based on K-OPLS method
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作者 LI Jun LI Kai 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2020年第1期17-27,共11页
Aiming at the problem of soft sensing modeling for chemical process with strong nonlinearity and complexity,a soft sensing modeling method based on kernel-based orthogonal projections to latent structures(K-OPLS)is pr... Aiming at the problem of soft sensing modeling for chemical process with strong nonlinearity and complexity,a soft sensing modeling method based on kernel-based orthogonal projections to latent structures(K-OPLS)is proposed.Orthogonal projections to latent structures(O-PLS)is a general linear multi-variable data modeling method.It can eliminate systematic variations from descriptive variables(input)that are orthogonal to response variables(output).In the framework of O-PLS model,K-OPLS method maps descriptive variables to high-dimensional feature space by using“kernel technique”to calculate predictive components and response-orthogonal components in the model.Therefore,the K-OPLS method gives the non-linear relationship between the descriptor and the response variables,which improves the performance of the model and enhances the interpretability of the model to a certain extent.To verify the validity of K-OPLS method,it was applied to soft sensing modeling of component content of debutane tower base butane(C4),the quality index of the key product output for industrial fluidized catalytic cracking unit(FCCU)and H 2S and SO 2 concentration in sulfur recovery unit(SRU).Compared with support vector machines(SVM),least-squares support-vector machine(LS-SVM),support vector machine with principal component analysis(PCA-SVM),extreme learning machine(ELM),kernel based extreme learning machine(KELM)and kernel based extreme learning machine with principal component analysis(PCA-KELM)methods under the same conditions,the experimental results show that the K-OPLS method has superior modeling accuracy and good model generalization ability. 展开更多
关键词 kernel method orthogonal projection to latent structures(K-OPLS) soft sensing chemical process
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What to Do for Three Gorges Project This Year?
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作者 周双超 《Electricity》 2001年第2期16-19,共4页
According to the planned schedule of Three Gorges Project: to realize initial water storage, electricity generation of first batch of hydro-generator units and open of permanent shiplock to navigation in 2003, this pa... According to the planned schedule of Three Gorges Project: to realize initial water storage, electricity generation of first batch of hydro-generator units and open of permanent shiplock to navigation in 2003, this paper presents the investment and amount of works to be completed for Three Gorges Project this year. In 2001, Three Gorges Project will be faced with a new aspect of construction: concrete pouring being in continuous high intense state; installation and erection of metallic structures, mechanical and electrical equipment as well as grouting works overall entering peaking year. 展开更多
关键词 Three Gorges Project investment amount of works installation and adjustment
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Thinking substation construction project management methods
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作者 HU Wenmin 《International English Education Research》 2015年第10期21-23,共3页
One of the most important tasks of security is the quality of the project substation substation construction project management, construction project management, including project bidding and engineering, electrical e... One of the most important tasks of security is the quality of the project substation substation construction project management, construction project management, including project bidding and engineering, electrical engineering and civil construction, engineering, quality control, safety management and supervision costs control, on-site supervision over the links, these links chain, indivisible, so long as a part of the management problems, will lead the entire construction project management effectiveness be affected, so it must be every link control and management work done, in order to guarantee the quality of the entire substation, in order to make security of supply substations, electrical safety and vital interests of users are protected. In this paper, the author details the three aspects substation construction management of the project, namely the concept of substation engineering, project management and construction safety, through these three aspects, the author analyzes the construction project management substation existing problems, To solve these problems and issues proposed some measures and construction process that need attention. It launched separately from the design, schedule, quality and other aspects of security and research, and in the course of the study stressed the importance of coordination between elements of construction and construction sectors as well as cooperation between the construction, explains the importance of the project cost control. 展开更多
关键词 SUBSTATIONS construction project management cost control BIDDING civil engineering
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隐形投工休矣
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作者 敏捷 《乡镇论坛》 1995年第3期22-22,共1页
隐形投工休矣近年来,一些山区乡村农民投工愈来愈多,义务工、建设工、非建设工名目之多、数额之大,远远超出了国务院规定的数目。据调查,有一个1200余人口的村,1994年投工总数达13万个,人均100余个。在这些投工中,... 隐形投工休矣近年来,一些山区乡村农民投工愈来愈多,义务工、建设工、非建设工名目之多、数额之大,远远超出了国务院规定的数目。据调查,有一个1200余人口的村,1994年投工总数达13万个,人均100余个。在这些投工中,非建设性的隐形投工占一定的比例,主... 展开更多
关键词 投工量 郧西县 农民负担 建设性 十堰市 无劳动能力 湖北省 义务工 农户经济 集体经济
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“根本问题”ABC
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作者 王伟漳 《广西农村经济》 1995年第1期11-14,共4页
长期以来,农村经济存在“三个难点”问题,在认识和实践中未获统一。一是把发展农业和农村经济放在经济工作的首位问题;二是农业内部处理好粮、钱关系问题;三是农业的投入问题。这三个“难点”问题,长期困扰着农村经济的稳定发展。
关键词 粮食 广西农业 根本问题 农业投入 经济工作 发展农业 农业内部 弱质农业 农村经济 投工量
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OPTIMAL BINARY CODES FROM ONE-LEE WEIGHT CODES AND TWO-LEE WEIGHT PROJECTIVE CODES OVER Z_4 被引量:7
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作者 SHI Minjia WANG Yu 《Journal of Systems Science & Complexity》 SCIE EI CSCD 2014年第4期795-810,共16页
This paper investigates the structures and properties of one-Lee weight codes and two-Lee weight projective codes over Z4.The authors first give the Pless identities on the Lee weight of linear codes over Z_4.Then the... This paper investigates the structures and properties of one-Lee weight codes and two-Lee weight projective codes over Z4.The authors first give the Pless identities on the Lee weight of linear codes over Z_4.Then the authors study the necessary conditions for linear codes to have one-Lee weight and two-Lee projective weight respectively,the construction methods of one-Lee weight and two-Lee weight projective codes over Z4 are also given.Finally,the authors recall the weight-preserving Gray map from(Z_4~n,Lee weight)to(F_2^(2n),Hamming weight),and produce a family of binary optimal oneweight linear codes and a family of optimal binary two-weight projective linear codes,which reach the Plotkin bound and the Griesmer bound. 展开更多
关键词 Gray map Lee weight one-weight codes projective codes two-weight codes.
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