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81.
王伟 《价值工程》2014,(17):315-316
本论文通过对几款服装三维试衣软件和在线试衣软件进行试用,同时对软件的基本功能进行对比研究,结合一些使用客户的评价,从客户的角度提出软件在功能方面存在的问题以及改进意见。  相似文献   
82.
为建立一种快速检测锦鲤疱疹病毒(CyHV-3)的环介导等温扩增方法(LAMP),本研究根据GenBank中登录的CyHV-3 TK基因编码区序列设计了LAMP特异性引物,通过优化反应条件,建立了检测CyHV-3的LAMP方法。表明本实验建立的该检测方法具有高灵敏度、高特异性、快速和简便的特性,适用于临床上对锦鲤疱疹病毒3的快速诊断。  相似文献   
83.
North America has few cultural agricultural landscapes, and often commensurately poor governance arrangements for managing change in such settings. This research uses the Acadian dykelands of Nova Scotia, Canada, as an opportunity to explore the social and governance limits to coastal climate adaptation in ‘new world’ cultural agricultural landscapes, as well as inform local decision-making. Approximately half of Nova Scotia’s coastal wetlands were converted to dykeland in the 1600s, lowering local resilience to the increased frequency and storm severity anticipated with climate change. Today, dykelands protect a diversity of public and private interests, meanings and values, yet are controlled by the agricultural sector, which can no longer afford to maintain them all to 2050 climate projections. We report here on a representative online Q-methodology survey of 183 adult Nova Scotians in the spring of 2015. Respondents sorted 34 statements along a normal distribution about whether they prefer dykeland maintenance or wetland restoration, and under what governance arrangements. Four factors were derived: the dominant discourse was local, female and strongly pro-dykeland, indicating the likelihood for local resistance to dykeland removal on for cultural, recreational and farming reasons. The second factor was supportive of wetland restoration for reasons of efficiency, not wetland affinity, but characterized by those in positions of management power. The two minority viewpoints were less informed about dykelands, characteristic of outsiders, and concerned more with governance. More education is needed about the challenges facing dykelands, the benefits of coastal wetlands, and the management options, but this research shows proposals to change landscape should emphasize flood mitigation over cost-saving. Cultural values and status quo bias are clearly barriers to adaptation planning, even when discussing the removal of man-made structures. The factors were surprisingly polarized, suggesting the forced-normal distribution affects the space available to convey nuanced perspectives. Large p-set Q-method of this kind is likely most useful for characterizing the emergent discourses demographically, and understanding their prevalence; the same discourses had emerged within a much smaller pilot study.  相似文献   
84.
This study employs the linear and nonlinear ARDL cointegration methodologies to examine the potential symmetric and asymmetric responses of suicide rates to unemployment rates in the US from 1928 to 2013. Our results suggest that suicide rates are pro-cyclical with respect to the business cycle (measured by changes in the unemployment rate) after extensively controlling for divorce and fertility rates. Unemployment has symmetric long-run effects on the age-adjusted suicide rate and four age-specific (from ages 25–34 to 55–64) suicide rates, while the effect of an economic expansion on suicide rates for those aged over 45 is greater than the effect of an economic recession. These findings imply that the effect of an economic expansion on the decrease of the suicide rate is higher than the effect of an economic recession on the increase of the suicide rate for individuals aged over 45. Therefore, intervention designed to reduce suicidal behaviors should emphasize periods of economic recession more than periods of economic expansion for those of middle age and beyond.  相似文献   
85.
86.
Regional corruptness in China has a positive effect on the profitability of private firms, but not that of state-owned firms. A natural experiment of exogenous trade policy change suggests that corruption may help private firms circumvent government regulation.  相似文献   
87.
Agricultural cooperatives in Africa tend to be community‐based organizations defined by principles of inclusion, voluntarism, democracy, equity, autonomy, mutuality and solidarity. This means that they generally operate in accordance with the principles endorsed by the International Cooperative Alliance (ICA). However, only a few of these organizations are successful in commercializing the agricultural produce of their members. In this study, we argue that growth‐problems leading to commercial failure and organizational degeneration in these cooperatives can be attributed to a lack of managerial capital. Drawing on the literature and evidence from the field we set out key management solutions for counterbalancing cooperative principles in the context of rural Africa. These solutions were taught to the leaders and managers of 362 cooperatives at four training events held in Madagascar, Malawi and twice in Uganda. Using a production function for cognitive achievement and key informant interviews, we find that our training contributed to the adoption of the proposed solutions by some of the cooperatives. Using the Ugandan sub‐ sample, we estimate an OLS regression and a PSM model to show that the training translated into higher revenues per member generated through collective commercialization.  相似文献   
88.
This study examines the nature of the relationship between formal agricultural credit and agricultural Gross Domestic Product (GDP) in India, specifically the role of the former in supporting agricultural growth, using state level panel data covering the period 1995–1996 to 2011–2012. The study uses a mediation analysis framework to map the pathways through which institutional credit relates to agricultural GDP relying on a control function approach to tackle the problem of endogeneity. The findings from the analysis suggest that over this period, all the inputs are highly responsive to an increase in institutional credit to agriculture. A 10% increase in credit flow in nominal terms leads to an increase by 1.7% in fertilizers (N, P, K) consumption in physical quantities, 5.1% increase in the tonnes of pesticides, 10.8% increase in tractor purchases. Overall, it seems quite clear that input use is sensitive to credit flow, whereas GDP of agriculture is not. Credit seems therefore to be an enabling input, but one whose effectiveness is undermined by low technical efficiency and productivity.  相似文献   
89.
Land greening in China is regarded as contributing a great deal to greening of the Earth. The phenomenon is mainly attributed to climate change, arising atmospheric CO2 and ‘Grain for Green’ (GFG) land management policies. However, limited knowledge is known how much land greening is from contributions of the GFG practice. Therefore, the study took the typical region of the GFG practice, the Loess Plateau, as the study area, and used 1982–2015 satellite-observed GIMMS3g normalized difference vegetation index (NDVI) data, ERA-Interim climatic variables (precipitation, temperature and solar radiation) and atmospheric CO2 concentration data with the help of a developed TPRC-based NDVI model to derive GFG-induced NDVI after 1999. Furthermore, this study tracked the spatial-temporal dynamics of GFG-induced NDVI and assessed contributions of the GFG practice to regional vegetation changes. Results showed that satellite-observed NDVI and TPRC-based NDVI both exhibited an increasing spatial pattern from the northwestern to southeastern Loess Plateau, but their greening trends were separately 0.0022 and 0.0009 per year in 1982–2015 (p < 0.05). Note that the satellite-observed greening trend was much steeper with a slope of 0.0056 per year after 2006 (p < 0.05). The subsequent analyses documented that GFG-induced land greening were largely responsible for the steep trend. In space, evident greening patterns began to be observed in the central Loess Plateau from 2006 to 2008, afterwards expanded towards eastern and southwestern Loess Plateau. In 2011–2015, the increase magnitude of GFG-induced land greening in the Loess Plateau averagely accounted for 8.5 % in comparison to estimated TPRC-based NDVI, but in six natural zones were various, ranging from 3.2%–15.7%. In some regions of central Loess Plateau, GFG-induced NDVI contributed even more than 20 % to vegetation increase. This study highlights that land use management contributes more to land greening dynamics over the Loess Plateau compared to climate change and arising atmospheric CO2 concentration. These findings likely provide some valuable information for curbing or enhancing specific-location vegetation changes in future regional land management and planning.  相似文献   
90.
文章利用2014年天津市武清区大气污染物臭氧(O_3)、二氧化氮(NO_2)和一氧化碳(CO)的监测数据,分析研究武清区O_3及其前体物NO_2和CO等大气污染物浓度水平和变化特征。结果表明武清区O_3浓度水平呈现明显的季节变化特征。夏季O_3浓度为106μg·m~(-3),冬季浓度为28μg·m~(-3),主要与光化学反应在夏季比较强烈,冬季紫外强度和平均温度均较低,光化学反应较弱有关。2014年武清区大气中NO_2年均值为51μg·m~(-3),CO年均值为1.9 mg·m~(-3),冬季是NO_2和CO浓度最高的季节。  相似文献   
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