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71.
[目的]利用内蒙古自治区乌兰察布丰镇市、凉城县、兴和县,辽宁省朝阳市朝阳县411个农户调查数据,分析玉米收储制度改革背景下北方旱作区农户杂粮种植影响因素。[方法]首先对户主个人特征、家庭禀赋两个一般影响因素进行分析,然后重点对自然和社会资源特征、市场环境、政策环境3个影响因素进行分析。[结果](1)由于户主年龄偏大且文化程度较低、户均从事农业生产的劳动力数量和拥有的耕地面积都较少,农户面对玉米市场价格下跌改种其他农作物的能力较弱;(2)尽管农户普遍认同杂粮适合当地自然条件,但是缺乏企业带动,订单种植杂粮的比例较低,农户种植杂粮存在较高的销售风险;(3)虽然农户普遍预期玉米市场价格持平和走低,但是多数农户对杂粮市场价格没有明确预期,杂粮收益存在较高的不确定性;(4)农户普遍不了解玉米收储制度改革的具体内容,且绝大部分农户没有获得杂粮生产支持,不利于引导农户种植杂粮。[结论]应从加强政策宣传、扶持杂粮加工龙头企业、扩大杂粮补贴范围等方面着手,引导北方旱作区农户种植杂粮,减少玉米收储制度改革对其收入的冲击。  相似文献   
72.
被动式传感器目标跟踪是多传感器多目标跟踪领域的一个重要研究方向。针对三被动式传感器多目标定位系统全局最优数据关联的三维分配问题,在允许传感器漏检和虚警的情况下,通过分析拉格朗日松弛算法,提出一种假定真实目标的快速收敛算法。该算法通过粗关联假定真实目标并重新修改代价矩阵,然后进行细关联,使得拉格朗日松弛算法在保证关联精度的前提下有效地提高了收敛速度。理论分析和实验结果表明,该算法提高了数据关联的速度,并在一定程度上提高了关联准确率。  相似文献   
73.
The main aim of this paper was to understand a guest’s decision to stay at a green hotel by using the theory of planned behavior (TPB) developed by Ajzen (1991). The population for this study was green hotel customers in Taiwan. A total of 425 usable responses were received from the willing participants around the parking area of green hotels. This study performed a PLS-SEM to examine the proposed model. The results of this study showed that social pressure has very little direct impact on behavioral intention to stay at a green hotel. The results of the estimated standardized regression coefficients and t-values indicated that perceived behavioral control has a slightly higher impact on behavioral intention than attitude. This study also verified the proposed mediating relationships between the first-order and second-order antecedents. This study provided theoretical and managerial implications for understanding respondents’ decision to stay at a green hotel.  相似文献   
74.
[目的]通过对山西省乡村休闲旅游地的空间分布特征及影响因素进行研究,旨在为山西省的乡村旅游发展提供合理的参考建议。[方法]选取山西省213处国家级和省级乡村旅游示范点为研究对象,运用最临近点指数对其空间分布类型进行判别,并运用地理集中指数和地理联系率对其分布均衡程度和地理联系程度进行考量,通过核密度图进一步分析其空间分布指向,在此基础上对影响因素进行分析。[结果]山西省乡村休闲旅游地空间分布呈集聚分布的特点,且与经济规模和人口密度在空间上的均衡、配合程度较高。[结论](1)山西省乡村休闲旅游地包括以太原和晋中为主的中部密集区和以临汾、运城、晋城为主的南部密集区,且都以各地级市为中心向周边扩展,大多数示范点分布于城郊地区; (2)经济发展、人口密度、资源禀赋、区位因素和社会因素是影响山西省乡村休闲旅游地分布的主要因素,其中农业科技类、农事体验类和特色村镇类多分布于经济和人口密度较高的地区。  相似文献   
75.
董恺  岳书铭 《科技和产业》2019,19(9):134-138
由于基层政府长期存在财力事权上的不均衡,我国基层地区义务教育供给存在着差距。2001年的"以县为主"的县统筹财政制度开始实行,义务教育的负责主体变成了县级政府。借助2002年到2016年的山东省县级数据,运用泰尔指数作为分析工具,结合此期间山东省出台的教育改革措施,分析其对于缩小义务教育差异的影响。研究发现,政策制度仅仅改善了中等收入县级地区之间的差距,对于高收入和低收入地区并没有太好的效果,就目标而言,由于县级各地区上经济实力和义务教育规模的固有差距,导致无法取得理想中的效果。  相似文献   
76.
[目的]目前我国正处于关键的经济转型期,生态农业和生态旅游业作为生态文明建设的重要产业之一,其耦合发展对于存进产业结构优化升级具有重要作用。[方法]通过构建生态农业与生态旅游业指标体系,采用灰色关联法计算江苏省生态农业与生态旅游业的关联度,进一步通过耦合协调度模型分析两者的协调程度。[结果]生态农业系统与生态旅游系统中的旅游经济、旅游资源和旅游价值的关联度分别为0.719,0.673和0.621,大小顺序分别为旅游经济旅游资源旅游价值,而生态旅游系统与生态农业系统中生态系统、经济系统和社会系统的关联度分别为0.687,0.700和0.626,大小顺序分别为经济系统生态系统社会系统,耦合作用均分别为较强、较强和中等。2012~2016年江苏省生态农业和生态旅游业耦合度处于磨合阶段,但一直在增加,同时耦合水平经历了初级协调发展水平到中级协调发展水平的过程。[结论]江苏省生态农业和生态旅游业的耦合发展仍有进步的空间,今后应加强耦合发展机制,推动两大耦合产业走向更深更广的发展领域,促进生态文明建设,同时保证生态产业的可持续健康发展。  相似文献   
77.
In this article we use the innovation survey of the manufacturing industry of Peru to identify cooperation behaviors for research and development (R&D) projects among companies and external agents in general. Likewise, we also find cooperation behaviors among the industry and the following external agents: university, technical centers, suppliers, customers, and companies of the same group, competitors, guilds, and consultants. Within the specific agents, the university is considered a cooperation agent for R&D projects. We use the survey of innovation in the manufacturing industry of Peru conducted in 2015, which resulted in 1447 Peruvian companies being surveyed. Evidence was obtained as to the degree of the tie between the industry and external agents for cooperation in R&D projects, giving relevance to variables such as investment, resources, and degree of innovation. Our results show that investment is an important factor for cooperation with external agents. Additionally, companies that have innovated at some point seek to cooperate with external agents. Finally, the importance of the university is demonstrable, thus, companies that invest in R&D seek to cooperate with the university.  相似文献   
78.
World tourism cities perform multiple functions and exhibit various characteristics that influence tourism development within their boundaries. They are the main gateway for tourists visiting a country and their success has a direct impact on the visitor economy of that destination. London, the focus of this research, has been one of the world’s top tourism cities for many years, and a key gateway for domestic and international visitors. But despite the important role tourism plays in the economy of the city, there is limited research on the development of this activity in the capital. Using London as an exploratory case study, this paper contributes to better understanding the challenges faced by policy makers when planning and managing tourism in world cities. The adopted research method offers the advantage of gathering insightful information using multiple data collection techniques. Examining this new evidence contributes to expanding the knowledge on the particularities of tourism development in one of the top world cities, which could help policy makers in their efforts to better prepare for potential challenges faced by these complex but important destinations.  相似文献   
79.
The paper examines the effect of population ageing on public education spending. On the one hand, ageing is expected to have a negative effect on education, as an increasing number of retirees results in ‘intergenerational conflict’ and, hence, the condemnation of education expenditure. On the other hand, ageing, in combination with pay-as-you-go pension systems, offers incentives for the working-age generation to invest in the public education of the young in order to ‘reap’ the benefits (that is, higher income tax/contributions) of their greater future productivity. Empirical evidence derived from the application of a fixed effects approach to panel data for OECD countries shows that the increasing share of elderly people has a non-linear effect on education spending. This indicates a certain degree of intergenerational conflict. Nevertheless, we find that future population ageing, which reinforces the mechanism linking public education and pensions, reflects positively on education expenditure. Furthermore, by disaggregating total education expenditure by educational levels, we observe that this effect is led by levels of non-compulsory education, probably as a reflection of the direct connection to labor productivity.  相似文献   
80.
Data Envelopment Analysis (DEA) window analysis with ideal window width is applied to evaluate the green technology innovation efficiency of 28 manufacturing industries in China during 2006–2014. The obtained results are compared with those calculated using the traditional DEA model, and convergence analysis of the efficiency is conducted. Five years is the obtained ideal window width and DEA window analysis with ideal window produces results closer to reality for China's manufacturing industry. The overall efficiency of the green technology innovation in the manufacturing sector is low following a wave-shaped curve – first decreasing, then increasing and decreasing again, with large inter-industrial differences. There are 8 high-, 14 medium- and 6 low-efficiency industries. A convergence trend in the green technology innovation efficiency within the 28 manufacturing industries exists, implying a catch-up effect between them.  相似文献   
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