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1.
《Socio》2019
Biofuels are emerging as a prominent renewable and sustainable energy sources in developed countries. In this sense, this paper presents a case study in which a biorefinery has to be sited in Northern Spain. Thus, the strategic decision of locating such a facility is deeply investigated through strategic policy evaluation. Then, tactical decisions ranging from purchasing and transportation policies to storage protocols are carried out. Only local and limited biomass can be harvested for supplying the biorefinery through a heterogeneous vehicle fleet. Moreover two different and mutually exclusive storage strategies are evaluated: direct supply from crops to biorefinery and using intermediate-collectors. Additionally, crop exploitation factors and biorefinery sizes are used to generate several scenarios in which the strategic decision of location as well as all the tactic decisions are made. Some mixed integer linear programming models are proposed to figure out all relevant decision problems.The results suggest that the Northwest study area as the best option to locate the biorefinery and recommend the intermediate-collector storage strategy. Moreover, the key information about critical biomass, crops and times are also provided. 相似文献
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通过对AGC进行升级改造,加入机组避振策略,能够让机组处于良好的工况下运行。避振策略包括设定单机禁止运行区、尽量少穿越振动区、小负荷分配策略、联合振动区判别等。改造后的AGC系统不仅满足调度的调峰要求,还减少了设备的磨损,对岩滩电厂经济运行有明显的促进作用。 相似文献
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The objective of this paper is to evaluate the effect of Plant Variety Protection (PVP) on the productive merit/yield increases of US seed varieties. As an example, we use wheat varieties, which are and have been available as both protected and unprotected under PVP from both the public and private sectors. We find evidence that PVP has contributed to the genetic improvement of wheat, using varietal trial data from Washington State. As the private open‐pollinated varieties exist only because of PVP and are higher yielding, these results indicate a clear public benefit from PVP. 相似文献
6.
The establishment of deep-rooted perennial species and their processing for biomass-based products such as renewable energy can have benefits for both local and global scale environmental objectives. In this study, we assess the potential economic viability of biomass production in the South Australian River Murray Corridor and quantify the resultant benefits for local and global scale environmental objectives. We model the spatial distribution of economically viable biomass production in a Geographic Information System and quantify the model sensitivity and uncertainty using Monte Carlo analysis. The total potentially viable area for biomass production under the Most Likely Scenario is 360,728 ha (57.7% of the dryland agricultural area), producing over 3 million tonnes of green biomass per annum, with a total Net Present Value over 100 years of A$ 88 million. The salinity in the River Murray could be reduced by 2.65 EC (μS/cm) over a 100-year timeframe, and over 96,000 ha of land with high wind erosion potential could be stabilised over a much shorter period. With sufficient generating capacity, our Most Likely Scenario suggests that economically viable biomass production could reduce carbon emissions by over 1.7 million tonnes per annum through the production of renewable energy and a reduced reliance on coal-based electricity generation. Our analyses suggest that biomass production is a potentially viable alternative agricultural system that can have substantial local scale environmental benefits with complimentary global scale benefits for climate change mitigation. 相似文献
7.
Stefan Ambec Corinne Langinier Stéphane Lemarié 《American journal of agricultural economics》2008,90(2):379-391
To reduce the competition from farmers who self-produce seed, an inbred line seed producer can switch to nondurable hybrid seed. In a two-period framework, we first investigate the impact of crop durability on self-production, pricing and switching decisions. Second, we study how the introduction of a fee paid by self-producing farmers affects those decisions. We find that the monopolist may produce technologically dominated hybrid seed in order to extract more surplus from farmers. Further, the introduction of a self-production fee improves efficiency. 相似文献
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World-wide, government institutions play an important role in the management of plant health. This paper develops a conceptual framework in which suppliers and demanders jointly determine the optimal level of plant health in a hypothetical market. Next this paper argues that this market falls short of reaching an optimal plant health situation due to the public good nature of plant health and due to the presence of asymmetric information. A range of commonly applied and novel solutions to this market failure are then discussed. 相似文献
9.
This study uses a sample of plant closings as the testing stage to examine the financial consequences of variant environmental performance records and stakeholder pressure levels. It compares 117 manufacturing facilities closing down between 1998 and 2000 to 351 facilities surviving through this period, along four measures of environmental performance. It shows that in the ten years prior to closure, closing facilities reduce their toxics emissions relatively more and incur somewhat stronger community and regulatory pressures than surviving ones. The results persist through alternative versions of the model and suggest that the environmental performance of closing facilities is at least as good as that of surviving ones. The mix of environmental practices of closing facilities differs from that of surviving ones with the former engaging in significantly less recycling of waste than the latter. Closing facilities focus more on end-of-pipe measures while surviving ones engage in more pro-active strategies, consistent with evidence in the literature of a positive relation between pro-active environmental practices and performance. Stakeholder pressures, in some cases (e.g., in pollution intensive industries), may be associated with unrecoverable costs to facilities, including closure, depending on the environmental management choices of the facilities. 相似文献
10.
Managing agricultural floodplains to meet present and future human requirements without jeopardizing biodiversity conservation is a challenge for land use planners and ecologists. This paper aims to disentangle the relationships between ecosystem services and biodiversity in multifunctional landscapes, such as floodplain agroecosystems, by disaggregating their values across land use types. We measured eight ecosystem services (gas regulation, soil formation, nutrient regulation, habitat provision, food provision, raw materials production, education, and recreation) and six plant diversity indexes (richness, abundance, and true diversity for both plant species and growth forms) in seven land use types identified in the floodplain of the River Piedra (Spain). We observed that all land use types provided services to some extent, but each one was better at providing certain services. Natural or semi-natural habitats provided more services and hosted greater diversity than cultivated land use types. In addition, five diversity indexes were strongly correlated to at least three ecosystem services each one. Habitat provision and education were the ecosystem services positively correlating to most diversity indexes, whereas food provision was negatively correlated to all diversity indexes. Moreover, analyzing the interactions between ecosystem services and biodiversity across land use types, we observed that land use type was the controlling factor regarding the sign and significance of the interaction. The results of this study suggest that, in floodplains agroecosystems, a mosaic landscape of different land use types helps support ecosystem services and contributes to maintaining biodiversity while using local resources. Such land use policies might manage agricultural floodplains at the landscape scale while still being able to accommodate specific measures for each land use type. Moreover, riparian forests should be preserved and restored across the floodplain as they are hot spots for biodiversity and ecosystem services provision. 相似文献