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排序方式: 共有655条查询结果,搜索用时 15 毫秒
91.
内蒙古是全国重要的乳品生产基地,乳品产业是该地区的特色产业、优势产业,其进出口贸易对内蒙古地区经济发展具有十分重要的作用。采用数据分析与理性思考相结合的方式,对内蒙古乳品产业发展现状及进出口情况进行分析,探讨该地区乳品贸易存在的问题,积极探索对策措施,以提高内蒙古乳品在国际贸易中的竞争力。 相似文献
92.
Larry R. Schaeffer 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2019,136(6):413-417
Interbull has been responsible for comparing dairy bulls across countries since the mid‐1980s. The current methodology is called MACE (multiple across country evaluations) which has been in use since 1995. Now that genomic data are being utilized in many countries, this has led to two serious problems. The first is that of preselection of young bulls such that the young animals are no longer a random sample of progeny from a sire by dam mating pair. Secondly, some countries are becoming less willing to share genomic data with Interbull. Both issues raise concern over the future of Interbull and international comparisons. This paper suggests a competition model as a potential replacement for MACE. The competition model makes pairwise comparisons between all pairs of bulls within a country and combines these differences across countries through bulls that are used in more than one country. Pedigree information is ignored as are all genomic data because bulls are treated as fixed. The model produces one international ranking of bulls averaging out any genotype by environment interactions which may exist. The competition model is illustrated by a small example. The limitations and advantages of the competition model are discussed. 相似文献
93.
关于修改《1972年国际海上避碰规则》增加有关从事捕鱼船舶条款的建议 总被引:1,自引:0,他引:1
为了使《1972年国际海上避碰规则》适应航海科学与技术的迅速发展,目前国际航海界正在讨论国际海上避碰规则的修改问题。随着我国远洋渔业的迅速发展,使我们对全球从事捕鱼作业的船舶情况有个基本的认识,笔者根据从事海洋渔业专业船舶避碰教学研究和海上渔业生产实践的体会,对避碰规则的修改提出增加关于从事捕鱼的船舶若干条款的建议。 相似文献
94.
95.
“一带一路”倡议、教育发展规划和世界城市建设为来华留学生教育提供了快速发展的契机和广阔的发展平台。北京农业职业学院在开展“一带一路”国家留学生教育过程中定位明确,创新管理模式,注重内涵发展,办出了特色,但也面临着项目规模偏小、学历教育留学生流失率高等问题。突破这一困境的主要方法包括配合企业订单式培养技能型人才,利用“互联网+”开放办学,挖掘学科优势建设全英文授课课程,加快国际化师资队伍建设等。 相似文献
96.
Summary A series of international trials with the potato crop was conducted in eight countries representing widely differing environments. The purpose of the experiments was: (1) to develop a method for obtaining environmental indexes which measure productivity of diverse potato-growing areas, and (2) to construct performance models for individual genotypes based on the environmental indexes. Yield data of 32 genotypes obtained from a series of 13 experiments conducted in the eight countries in 1983 and 1984 were used in the study. The response pattern of the genotypes was studied by a multivariate analysis. Five genotypes were chosen as representatives for different response patterns to the environments and their data were used for calculating a series of independent indexes for each of the experimental sites based on principal component analysis. Performance models for each of the genotypes were constructed by stepwise regression analysis of yields of a genotype on the environmental indexes based on 1983 data. Yield data of 1984 experiments were used to verify the models. Satisfactory correspondence between observed and predicted yields was obtained for most of the genotypes. 相似文献
97.
目标价格政策对中国棉花市场影响分析 总被引:1,自引:0,他引:1
棉花目标价格试点是中国完善农产品价格形成机制的重要举措,经过1年的试点,棉花产业各市场主体对目标价格政策基本适应。通过对临时收储政策和目标价格政策下国内棉花市场价格走势、国内外棉花价差变化情况、中国棉花进口情况3个方面的对比分析,认为目标价格政策下,中国棉花市场价格逐步由供求决定,棉花加工企业资源开始优化整合,棉纺织企业经营状况趋于好转,内地棉区种植面积将大幅减少。 相似文献
98.
梁乘 《北京农业职业学院学报》2021,35(3):13-19
近年来,我国招收的国际学生数量保持快速增长,生源结构呈现多元化特点,来华留学事业进入稳步发展阶段.国际学生的思想政治教育是新时期高等教育提质增效的重要内容之一,为了使国际学生能够更加客观地认识和理解我国的政治、经济、文化、法律和制度,成为中外友好沟通交流的纽带和桥梁,高校应从完善培养体系、加强系统性和针对性、创新教育形式、完善相关制度、加强队伍建设五个方面,推进国际学生的思想政治教育工作,更好地为我国教育事业和外交战略服务. 相似文献
99.
The COVID-19 outbreak has shocked the world's economies in the year of 2020. As this pandemic spreads around the globe, many experts feared that the global food supplies might start running short, especially if supply chains were disrupted. COVID-19 also added to the uncertainty of the business operation. Therefore, it is critical to understand how COVID-19 pandemic affected global food supply and market. In this study, we investigate the impact of COVID-19 on agricultural export companies in China using a unique firm-level survey data. We found that although on average agricultural businesses experienced declines in the exports, exports of some agricultural products especially grain and oil held strong and even increased, implying the essential demand for staple food during the pandemic. Not surprisingly, exports of medicinal herb also increased significantly during the pandemic. However, exports of goods such as edible fungus and horticultural products sharply decreased. Our results also showed that in general, impact of COVID-19 on smaller firms was more severe than that on larger firms. The results of this study can provide useful guidance and implications for agricultural businesses and policy makers on their COVID-19 mitigation efforts to navigate this global pandemic. 相似文献
100.
产于陕西八百里秦川的秦川牛,千百年来一直是关中农业生产的主要动力和粪肥来源,建国后,通过广大科技工作者的通力合作,协同攻关,运用国际育种先进技术,选出优秀公牛,授配主产区大批秦川母牛,配合其他措施,从而加速了秦川牛的选育,使之很快由役用型转变为肉用型,形成了秦川肉牛新品系。经屠宰测定,其肉用,役用性能不仅大大高于50年代调查时测定的指标,而且其中一些肉用性能指标与国际著名的肉牛品种相比也毫不逊色, 相似文献