阶梯可调毛细管组件的应用研究

为实现设备出厂后毛细管组件可以根据现场工况阶梯调节,保证每台空调器工作性能达到最优,开发一种新型阶梯可调毛细管组件。对毛细管组进行了优化组合,确定了毛细管组件的尺寸。实验测得基于阶梯可调毛细管组件的2匹小型地源热泵在不同工况下的制热量与COP,较同型号的单一毛细管机组的制热量和COP最高可提高15%。     

谈地方产业群通道的建立

产业群的发展对地方经济发展具有重大意义 ,是迎接经济全球化的必然要求 ,为此要打通如下通道 :发展壮大中小企业 ;地方政府要加强企业之间的相互合作 ;要切实解决条条块块分割的问题 ;要培养产业群的“嵌入性”及“根植性” ;要建立地方产业群发展必须的中介组织、服务机构及基础 ;地方政府要转变职能 ,完善制度 ,打通地方产业群的宏观通道。     

导师制教学在小规模士官职业技术教育中的应用

小规模士官职业技术教育是军队院校职业技术教育的重要组成部分,分析了小规模士官职业技术教育的特点,详细论述了导师制教学流程及各个教学环节中的具体事项,并将导师制教学应用于《XX测试设备维修》课程,并取得了较好的教学效果。     

中小型图书馆如何开展实时数字参考咨询服务

实时数字参考咨询服务作为一种全新的信息服务方式,已得到越来越多的图书馆的重视。国内中小型图书馆开展实时数字参考咨询服务,要在软件选择、队伍建设、合作服务、宣传推广等四个方面做好工作。     

小企业成长阶段的战略匹配与控制

战略管理的过程是一个动态的过程,它随着小企业外部环境和自身条件的变化而变化。小企业在成长的不同阶段,必然要通过战略的调整来指导企业的行为,选择不同的成长战略。同时,在小企业成长的不同阶段,要通过整合信念系统、边界系统、诊断控制系统和互动控制系统4种杠杆保持战略的有效性。     

增值税两类纳税人身份选择的新思考

我国现行税收政策上的差别造成了增值税两类纳税人税收负担上的差别,也为纳税人选择税收身份进行税收筹划提供了可能性。本文对目前国内主流的税收筹划教材、书籍及相关刊物上关于增值税两类纳税人身份选择的税收筹划方案提出了质疑,站在纳税人税后利润最大化的角度对其进行了分析和总结,得出了与前者不同的结论。     

对小规模纳税人税收负担现状的实证分析

通过对小规模纳税人税源质量和实际税负进行客观考核,分析调查样本税收负担现状,评价税收征管工作,探索新形势下小规模纳税人税收征管实践的有效方法和手段。     

基于遗传算法的小型物资托盘装载布局研究

为保证物资流通的高效快速,必须实现小型物资的集装化运输。研究小型物资托盘装载的核心是研究三维箱体布局问题。为简化计算,可将三维装箱问题转化为二维装箱问题,通过建立相应的数学模型,提出求解模型的遗传算法,根据应用实例对算法的有效性进行验证。     

Why do medium- and large-scale farmers succeed practicing CA and small-scale farmers often do not? – experiences from Paraguay

Conservation agriculture (CA) is defined as a system comprising no or minimum mechanical soil disturbance, permanent organic soil cover, and crop species diversification [FAO. (2014). What is Conservation Agriculture? FAO CA website, consulted on 15.09.2014. Retrieved September 15, 2014, from http://www.fao.org/ag/ca/1a.html]. The vast majority of medium- and large-scale farmers in Paraguay and neighbouring countries (Argentina, Brazil, and Uruguay) who use tractor-based farming systems have moved from conventional agriculture and adopted CA through no-tillage technologies. Among this farmer type, very few wish to return to the old system of tillage agriculture. However, despite massive efforts to transmit the technology to small-scale farmers by development aid projects and local governments, widespread adoption of CA has not happened on farms that use animal traction or manual farming systems; in fact significant dis-adoption of CA practices by smallholders has occurred. Some of the reasons for this dynamic are analysed in this paper. The reasons for dis-adoption by small-scale farmers can be generally divided into two groups. One group has to do with the fact that, comparatively, small-scale farmers are less able to cope with the factors related to CA (e.g. degraded soils, recuperating and maintaining soil fertility and know-how) than medium- and large-scale farmers. The second group of reasons has to do with the approaches and strategies that development aid agencies and local governments have taken towards small-scale farmers, which have influenced small-scale farmers’ ability to adopt and maintain CA practices. Small-scale farmers’ main asset is the soil and the CA/no-tillage system is a knowledge-based, learning-intensive system. However, despite the technical support provided by aid agencies and local governments, small-scale farmers often lack a deeper understanding of the CA concepts and practices. This is attributable to the short- to medium-term and rather conservative transfer-of-technology approaches that have been applied by development aid agency and local government programmes over the years, without any changes and without adaptive research. The latter can be derived, for instance, from the accountability of results to donor agencies or the one-size-fits-all approach applied in order to achieve ‘numbers’. One consequence of this is that ownership by and empowerment of farmers is often absent among dis-adopters. It therefore seems more suitable to apply long term, adaptable approaches to CA with smallholders. The lessons learned in Paraguay may well serve to properly direct future development intervention efforts in this country and also serve to mend development strategies in other countries in South and Central America, Africa or Asia.