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91.
本文对各国的农业产业化经营组织进行对比分析,把国外农业产业化经营组织模式分为4种类型:合同制、农业合作制、农工商综合体和联营体。对该4种类型的概念、特点及其适应条件进行了分析和论述。 相似文献
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Knut Egil Bøe Tor Gunnarson Homme Grete Helen Meisfjord Jørgensen 《Acta Agriculturae Scandinavica, Section A - Animal Sciences》2018,68(4):202-206
ABSTRACTThe aim of this study was to investigate the use and capacity of electronic feed stations (EFS) on commercial sheep farms. The study was conducted on four commercial farms and the numbers of pregnant ewes per EFS were 36, 70, 72 and 80, respectively. Each farm was visited once and behavioural observations were carried out. In addition the date and time for both entering and leaving the EFS and the amount of concentrates dispensed at each visit for extracted. The vast majority of the ewes used the EFS regularly. The number of rewarded visits per ewe per day varied from 3.2 to 5.9, whereas the number of unrewarded visits ranged from 6.0 to 21.5 per ewe per day. We conclude that feeding concentrates to groups of pregnant ewes in EFS function satisfactory, but the design of the entrance and exit gate still have to be improved considerably. 相似文献
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The aim of this study was to discriminate four commercial brands of Portuguese honeys according to their botanical origin by sensor fusion of impedance electronic tongue (e-tongue) and optical spectroscopy (UV–Vis–NIR) assisted by Principal Component Analysis (PCA) and Cluster Analysis (CA). We have also introduced a new technique for variable selection through one-dimensional clustering which proved very useful for data fusion. The results were referenced against standard sample identification by classical melissopalynology analysis. Individual analysis of each technique showed that the e-tongue clearly outperformed the optical techniques. The electronic and optical spectra were fitted to analytical models and the model coefficients were used as new variables for PCA and CA. This approach has improved honey classification by the e-tongue but not by the optical methods. Data from the three techniques was then considered simultaneously. Simple concatenation of all matrices did not improve the classification results. Multi-way PCA (MPCA) proved to be a good option for data fusion yielding 100% classification success. Finally, a variable selection method based on one-dimensional clustering was used to define two new approaches to sensor fusion, and both yielded sample clusters even better defined than using MPCA. In this work we demonstrate for the first time the feasibility of sensor fusion of electronic and optical spectroscopy data and propose a new variable selection method that improved significantly the classification of the samples through multivariate statistical analysis. 相似文献
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综述人工味觉系统在茶叶感官品质评价中的应用进展,主要包括茶类区分、品质相关性分析、品质定量分析等,并提出ATS(Artificial taste systems)在茶汤预处理标准化、传感器稳定性和灵敏度的提高、模式识别技术的开发等方面的发展前景. 相似文献
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方兴林 《黑龙江八一农垦大学学报》2012,24(2):100-102,108
随着互联网的普及,电子商务作为一种全新的贸易方式和商业模式开始出现。针对当前校园电子商务发展过程中遇到的问题,本文从客户群体、服务内容和商业氛围三个方面详细分析了校园环境的特殊性,并提出了一种全新的基于易物思想的校园电子商务发展新模式,它很好地满足了高校校园环境的要求,业务流程简单、规范,具有无需设置物流配送中心、第三方支付平台等诸多优点,具有很强的可行性和实践意义。 相似文献
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文子明 《信阳农业高等专科学校学报》2012,22(3):45-47
抗战时期,皖南重镇屯溪的商业繁荣,主要表现为:各种行业比较兴盛、经营类型多元化、商业组织逐渐完善。屯溪商业的繁荣得益于优越的地理位置、大量机关难民的迁入和众多的过往人员。 相似文献