3s技术在基本农田调查清理中的应用——以重庆市巫山县为例

划定永久基本农田是实现耕地保护目标的重要手段,为做好永久基本农田调整完善工作需要对基本农田现状进行调查清理,以重庆市巫山县为例,提供基于3S技术支撑的技术方法和工作思路。结果表明,以3S技术手段进行基本农田现状调查清理,能快速、准确查清基本农田现状数据中不符合基本农田划定要求的地类,能满足基本农田动态监测的需要,将更好地在基本农田划定与保护中得以应用。     

矿井通风三维可视化系统及优化

系统建立了三维仿真框架,建立了三维空间属性模型和非空间属性模型,分别对空间数据和非空间数据进行储存和管理。并建立了Hardy-Cross迭代模型和离散反馈型神经网络模型优化通风网络模型。并以C#语言来实现系统的功能。     

Crowdfunding: The collaborative economy for channelling institutional and household savings

The financial disintermediation mechanism known as “loan-based-crowdfunding” has recently come under regulation in several countries. This competitive investment and finance vehicle is already well established in the US and British markets.By compiling empirical data from a reference crowdfunding platform, this article compares loan-based crowdfunding with traditional investment vehicles such as investment funds, equities or pension funds.The conclusion of the study is that saving through crowdfunding allows the optimization of a portfolio comprising both institutional and retail investors.     

The Global Financial Crises of 2007–2010 and the future of capitalism

This paper presents an analysis of the 2007-2010 Global Financial Crisis which started with the sub-prime crisis in the U.S. and became global very fast. It argues that the financial system in the United States is a complex interlocking structure of markets, institutions and regulators. The causes and culprits of the crisis, the misaligned incentives of participants and exogenous events such as the wars in Afghanistan and Iraq, precipitated failure in key markets: commodities, sub-prime housing, equities, and credit. One of the strategic consequences of this crisis is that the US will lose its dominance in world power, the frequent crises and vulnerabilities of the Neoliberalism and examines the future of capitalism. Of the alternatives to economic system, the capitalism is the most viable economic system. However, it must adopt real and efficient allocation of resources to maximize welfare of all parties and seriously address the income inequality. It must reject crony capitalism, enact true financial regulation of institutions and markets, end corporate socialism and address the system’s structural deficiencies.     

Revisiting the relationship between suicide and unemployment: Evidence from linear and nonlinear cointegration

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.     

The stained China miracle: Corruption,regulation, and firm performance

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.     

Understanding the impacts of ‘Grain for Green’ land management practice on land greening dynamics over the Loess Plateau of China

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.     

天津市武清区大气O_3、NO_2和CO浓度变化特征研究

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。     

Foreign investment,corporate governance and performance in the Chinese listed A Share companies

We present a novel lens on the presence and impact of qualified foreign institutional investors (QFII) in top shareholdings of the non-financial domestically listed Chinese ‘A’ share firms. The initial results suggest that the presence of a QFII as a top shareholder in these companies is associated with their better performance, using both Tobin’s Q and ROA as the performance measures. Our models include variables representing corporate governance mechanisms, foreign legal person shares, a proxy for international affiliations and a number of time-variant firm characteristics. Economically, the coefficient of impact on the market measure is the more significant, while the effect of having a QFII in top shareholdings on both performance measures is empirically significant. Previously, studies have often ignored the potential for reverse causality beyond using lagged regressors. This is problematic. Therefore, we follow up with a 2SLS instrumental variables and system GMM model to further mitigate this potential and find the empirical relationship holds. Contrary to earlier work on QFIIs and governance post-implementation of the QFII scheme, the findings from our models suggest that the presence of a QFII top shareholder augments market performance holding equal existing corporate governance mechanisms and other controls.     

Gold and the US dollar: Hedge or haven?

Using a model of dynamic conditional correlations covering 23 years of weekly data for 16 major dollar-paired exchange rates, this paper addresses a practical investment question: Does gold act as a hedge against the US dollar, as a safe haven, or neither? Key findings are as follows. (i) During the past 23 years gold has behaved as a hedge against the US dollar. (ii) Gold has been a poor safe haven. (iii) In recent years gold has acted, increasingly, as an effective hedge against currency risk associated with the US dollar.