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1.
The Basel Capital Accord (pillar 3) states that disclosure of information (transparency) is essential to financial stability. This study analyzes, through inflation reports, the disclosure of information from the Central Bank of Brazil concerning the credit market. We consider credit risk and capital buffers as measures of financial stability in this analysis. Furthermore, in order to measure the perception of the monetary authority on the credit market, we built two indices based on the central bank’s communication on credit development. We performed a panel data analysis based on a sample of 125 banks for the period from June 1999 to September 2014 (7000 observations). The findings suggest that central bank communication regarding expectations concerning the credit market contributes to financial stability. Therefore, this kind of communication of central banks (about credit development) may constitute an important macroprudential tool to improve financial stability.  相似文献   
2.
This paper provides a policy commentary on the collapse in 1991 of the Australian Reserve Price Scheme for wool. A key cause of the collapse in the Scheme was a change in the RPS's governance arrangements, which led to increased political pressures to raise prices to unsustainable levels. In addition, in this paper an estimation has been made of the direct, upfront costs of the operation of the scheme, drawing on the financial accounts of the various agencies operating the RPS and subsequent wool stockpile. This was undertaken to determine the scale of the policy failure.  相似文献   
3.
Wool is the only Australian commodity for which there has been an attempt to organise price stability through a buffer stock scheme (1970–91). Growers pressed for the introduction of a scheme since the early 1920s. We test the veracity of claims that the sale of the stockpiles optimised growers' returns. We also simulate the likely outcomes of the reserve price schemes (RPS) proposed in 1925 and 1952, respectively. Our findings are that post-war stockpile disposals did not optimise wool growers' incomes, the undercapitalised proposed RPS of the 1920s would have collapsed in the depression, and that the post-1952 RPS would have been in considerable difficulty.  相似文献   
4.
城市自生群落具有重要的生态服务功能与潜力,但因其外貌不被公众所接受而难以在城市公共空间中应用。将群落生态学和设计学相结合,探索一种介入栽培植物对城市自生群落进行改良,最终形成具有一定美学价值的植物群落的途径。实验以植物群落设计美学原理和种间竞争原理为依据,向已经演替1年的城市自生群落中引入63种栽培植物,按照分层的方式对群落进行改良。3年的观测结果表明,有61.9%的栽培植物可以在城市自生群落中定居并建立优势,能对76.7%的自生植物起到抑制作用,使55.8%的自生植物消失。相比城市自生群落,改良后的群落美观度提高29.4%,公众接受度提高24%,群落的物种丰富度提高至2.29倍。相比一般的人工植物群落,改良后的群落可以节约58.2%的建植成本,降低83.9%的浇水成本和67.8%的除草成本。实验证明改良设计是一种可行的群落设计途径,能有效提高群落的物种丰富度和美学价值,同时让自然参与群落设计过程,实现人与自然的合作。  相似文献   
5.
The main purpose of this article is to empirically investigate the interactions between changes in capital buffer and changes in credit risk, using panel data of Islamic and conventional banks located in the Middle East and North Africa (MENA) region over the period 1999–2016. A negative two‐way relationship between the changes in capital buffer and the changes in credit risk is found for the two types of banks, that is, banks tend to decrease their capital buffers in response to an increase in risk exposure and limit their risky activities in response to an increase in their capital buffers. Dividing our period of study into three subperiods to assess the effect of the last financial crisis 2007–08 on the adjustment process, we point out the negative bidirectional relationship between the changes in capital buffer and the changes in credit risk of the two types of banks is present for the three subperiods except the case of conventional banks during the precrisis period. Moreover, we provide evidence that Islamic banks adjust their capital buffer in response to the changes in credit risk regardless of the existence or not of a deposit insurance scheme. In contrast, the negative two‐way relationship between the changes in capital buffer and the changes in credit risk in conventional banks is found only in countries without deposit insurance schemes.  相似文献   
6.
7.
Desertification and land degradation are worldwide problems affecting soil, vegetation and the livelihoods of rural populations. Bowal (plural bowé) is a particular form of degraded land that occurs in tropical regions and leads to the exposure of ferricretes, which are unsuitable for farming. Bowé are more common on farmland and degraded savanna. Changes in land use/land cover were used to map a region of 6.7 million ha in northern Benin, West Africa in 1975, 1990 and 2010. The changes observed during these periods (1975–1990, 1990–2010 and 1975–2010) were used to predict the occurrence of bowé in the period up to 2050 using Markovian chain analysis. The results showed a considerable change in land use/land cover during the three periods. The types of land on which bowé occur (farmland and degraded savanna) increased in northern Benin by 5.4% per year during the period 1975–1990 and 9.5% per year during the periods 1990–2010, while the natural vegetation (forest, woodland and tree savanna) decreased by the same amount. The future scenarios also predicted the same trend. In the period 1975–1990, 1.28 million ha (26%) of natural vegetation was converted to degraded savanna and farmland while 2.23 million ha (53%) of natural vegetation was converted to degraded savanna and farmland in the period 1990–2010. Based on the dynamics recorded during the period 1975–1990 and 1990–2010 respectively, a total of 1.28 million ha (26% of the natural vegetation that was present in 1975) and 1.29 million ha (31% of the natural vegetation that was present in 1990) will be converted to farmland and degraded savanna in the study area by 2050.Thus bowalization will persist and increase in the period up to 2050. The natural vegetation could disappear if protection and restoration measures are not taken. It is thus important to take measures to stop the degradation and to implement programs to restore soils on bowé based on the soil and water conservation techniques used on highly degraded West African soils, such as zaï pit and stone rows with grass strips. Some native plants species adapted to bowalization and resistant to climate change in northern Benin (e.g. Asparagus africanus, Andropogon pseudapricus and Combretum nigricans) should be used in association with soil and water conservation techniques on bowé.  相似文献   
8.
[目的]文章以马铃薯关键生长期——结薯期为测量时点,以马铃薯和玉米、大豆、水稻为研究对象,开展高光谱曲线特征差异性研究。[方法]为更好地描述马铃薯与其他作物的光谱差异,创建高光谱反射率差异性指数、高光谱一阶导数差异性指数、高光谱红边幅值差异性指数、高光谱曲率差异性指数及高光谱植被指数差异性指数。[结果](1)马铃薯与玉米、大豆、水稻3种作物光谱曲线具有明显差异,马铃薯与玉米的反射率值在480nm附近蓝色波段位置差异最显著,差异性指数值为67.866%,与大豆、水稻的最大差异性指数值分别为49.068%、57.559%,均位于550nm附近绿色波峰位置;(2)作物光谱曲线经一阶导数变换运算,马铃薯与其他作物间的光谱差异被显著放大,在近红外波段放大程度最显著;(3)马铃薯与玉米、大豆、水稻高光谱曲率差异性指数最大值均位于波长750nm附近,差异性指数值分别为78.365%、63.471%、80.882%;(4)常用植被指数中,比值植被指数、增强型植被指数可显著区分马铃薯与玉米、大豆、水稻。[结论]差异性分析结果为农作物空间分布遥感识别提供了技术支撑。  相似文献   
9.
通过利用喀什市研究区2012年的资源三号卫星影像,使用ERDAS软件首先提取归一化植被指数(NDVI),再使用Arc GIS软件对研究区的植被覆盖度进行估算,最后得出研究区2012年的植被覆盖度分级图,定量地说明了研究区2012年的植被覆盖情况。  相似文献   
10.
基于光能利用率模型的河南省冬小麦单产估算研究   总被引:2,自引:0,他引:2  
[目的]快速、准确估算空间尺度上作物产量,对于评价农田生态系统对气候变化的响应、制定科学合理的粮食政策、对外粮食贸易等具有重要意义。河南省冬小麦产量占全国1/4,准确估算河南省冬小麦产量对维护国家粮食安全具有重要作用。单产估算作为农作物估产中的关键技术,也是作物估产的难点之一。[方法]文章首先利用VPM(Vegetation Photosynthesis Model)估算冬小麦NPP(Net Primary Product),结合收获指数、冬小麦收获部分的含水量、含碳量、NPP分配到地上或地下部分比例等一系列符合该研究区的经验指数,进行河南省冬小麦单产估算研究,并分析了引起模拟误差的原因。[结果]模拟单产较实测单产低估4.4%(实测单产为6 810kg/hm~2,模拟单产为6 519kg/hm~2),但两者之间存在显著相关关系,两者相关系数的平方R2=0.70(n=50,p0.01)。通过与MODIS-GPP产品获得的冬小麦单产数据比较,基于VPM模型的模拟结果优于MODIS-GPP产品。[结论]基于VPM可快速、准确估算河南省空间尺度冬小麦单产,该方法具有较好的适用性。  相似文献   
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