我国现代农业发展的现状、问题与对策研究

近年来,在科技支撑和制度支持的背景下,我国的现代农业得到了长足发展,取得了举世瞩目的成绩。但是在发展过程中也出现了很多问题,例如:与发达国家相比,科技装备相对落后,现代农业人才严重短缺,金融支持力度不足,市场机制不完善等,因此深入研究现代农业具有重要的现实意义。文章首先对何为现代农业进行了详细阐述;然后分析了我国现代农业发展的现状;再次分析了我国现代农业发展中存在的主要问题;最后提出了切实可行的对策,为现代农业发展提供一些参考,促进现代农业科学发展。     

Research on Crop Irrigation Schedules Under Deficit Irrigation—A Meta-analysis

Water Resources Management - Increasing water consumption in agriculture due to global climate change has posed considerable challenges to food security, thus improving the efficiency of water...     

Study on Runoff Control Effect of Different Drainage Schemes in Sponge Airport

Water Resources Management - The low impact development (LID) concept aims to control storm runoff and pollution through decentralized, small-scale source control to bring the development area as...     

事业单位财务档案管理体系建设研究

随着事业单位经济活动不断拓展,单位管理要与时俱进,不断创新,财务档案与经济活动息息相关,是事业单位管理的重要抓手,加强财务档案管理是提高事业单位经济管理能力的重要途径。文章立足事业单位,针对其管理特点,结合国家政策法规,详细介绍财务档案管理的必要性及管理现状,并通过管理实践,展示了财务档案管理流程和方法,是理论与实践的有机结合,对事业单位加强财务档案管理,提升整体管理水平具有重要借鉴意义。     

Why will Trump lose the trade war?

ABSTRACT

The escalating U.S.–China trade conflicts have increasingly shadowed the outlook of the world economy. The Trump administration aims to achieve its strategic goals including reducing current account deficits, promoting the U.S. manufacturing sector, and curbing Chinese high-tech industries by waging the trade war against China. This paper argues that the current account deficits and the declining manufacturing sector in the U.S. are mainly driven by its internal structural factors, such as low saving rates, high labor costs, and rising service sector, rather than by the import competition from China. Moreover, the trade war further deteriorates the U.S. current account deficits and erode its comparative advantage, and it forces China to invest more in technological innovation and human capital, and thus promote its progress in high-tech industries. Thus, the U.S. will not be able to achieve its strategical goals and eventually lose the trade war.     

R&D Investments and Tax Incentives: The Role of Intra-Firm Cross-Border Collaboration*

U.S. multinational corporations increasingly use intra-firm, cross-border research collaboration to disperse R&D across different countries. This paper investigates the implications of such collaboration on the abilities of firms to garner benefits from R&D tax incentives. We find that the association between R&D intensity and tax incentives is three to five times larger when firms have extensive cross-border collaboration connected to a country. We also find that the effect is stronger when local intellectual property protection is weaker and when local innovation resources are higher. Our results suggest that cross-border collaboration helps firms achieve more tax-efficient R&D investments both by reducing the nontax frictions posed by weak intellectual property protection and by increasing the nontax benefits of foreign R&D.     

三门峡地区黄土工程特性

三门峡地区广泛分布第四纪黄土及黄土状土,通过分析该地区黄土的颗粒成分、矿物成分、化学成分、微观结构特征,分析了黄土的工程特性,结果表明:该地区Q3黄土的组成与中更新统黄土的矿物组成基本相近,颗粒组成以粉粒为主,黏粒含量大于我国西北地区,粉粒含量小于西北地区;全新统黄土、晚更新统黄土为中等、强湿陷性黄土,湿陷性系数为0.020~0.098,中更新统黄土一般不具有湿陷性。     

县域特色产业集群高质量发展研究

县域特色产业集群的快速发展有效推动了当地经济发展,在市场中形成了规模优势和竞争优势,是构成经济持续发展的关键动力.但是当前在发展过程中出现了较多的问题,影响了其发展质量和发展速度,基于此,本文对县域特色产业集群的发展优势、发展问题和发展策略进行了分析,以期可以为其高质量发展提供有效参考,扩大发展规模.     

基于AD9361的掌上型LTE RRU设计与开发

当前小体积远端射频单元（Remote Radio Unit,RRU）主要是皮站级别的Pico-RRU，其重量和体积仍然难以满足掌上型的要求。为此，采用高集成度的AD9361芯片来实现长期演进（Long Term Evolution，LTE）宽带收发信机功能，配合时钟同步模块、放大器模块和控制接口电路等一起构建低成本的掌上型RRU。主要解决了基于AD9516的时钟同步、低相位噪声设计和高灵敏度接收机设计三个技术难点，成功实现了掌上型、高性能、低成本的设计目标。整个RRU样机尺寸为18 cm×10 cm×2 cm，质量约500 g，量产成本千元以内。测试表明，该RRU下行误差向量幅度（Error Vector Magnitude，EVM）小于3%，优于3GPP要求的8%；10 MHz带宽时上行接收机灵敏度优于3GPP要求的-93.5 dBm。     

大同市水资源开发利用状况与承载能力的思考

文中分析了大同市水资源开发利用的状况，并对水资源承载能力的有关问题进行了讨论。