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我国经济增长模式对物流业发展的交互影响机制研究
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作者 徐寅骞 《中国市场》 2010年第49期14-15,共2页
本文通过分析1991—2006年我国的物流和经济增长相关数据,研究了我国经济增长模式与物流业发展的交互机制,并提出当前我国物流业和国民经济增长的交互作用主要是通过工业物流的发展来实现的。
关键词 GDP构成 物流需求系数 产业利用率
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Current Status and Perspective Development of Broomcorn Millet Production in China 被引量:1
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作者 刘猛 赵宇 +1 位作者 刘斐 李顺国 《Agricultural Science & Technology》 CAS 2012年第11期2438-2441,共4页
[Objective] This paper analyzed present status of broomcorn millet produc- tion in China, including cultivation methods, fertilization utilization, diseases, insect pests and disasters, machinery development, planting... [Objective] This paper analyzed present status of broomcorn millet produc- tion in China, including cultivation methods, fertilization utilization, diseases, insect pests and disasters, machinery development, planting benefit and other aspects. [Method] The corn millet data reported by China Industrial and Technological Re- search System of Millet in 2011 were analyzed by descriptive statistical analysis of EXCEL. [Result] The results show that 17 678.57 kg/ha of farm manure, 155.77 kg/ha of urea, 259.5 kg/ha of compound fertilizer, 203.13 kg/ha of phosphate fertilizer and 75 kg/ha of potash fertilizer were used in China; the national mechanization degree of broomcorn millet production is lower than 30% in all; the average income of broomcorn millet production is 10 503.33 yuan/ha, and the VCR is 2.64; most broomcorn millet producing areas are affected by mild pests and diseases, very few are affected by mild and moderate pests and diseases, and the impact of natural disasters is the lightest. [~onclusien] Currently fertilizer utilization for broomcorn millet is proper but the mechanization level and planting benefit are low, natural disasters, pests and diseases are not severe; finally the authors proposed some suggestions on the fertilizer utilization, mechanization production, benefit increasing, disaster warning, disease and insect controlling and government policy-making for broomcorn millet production. 展开更多
关键词 Broomcorn millet Production status Development proposals China
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Evaluation for Use Efficiency of Agricultural Resources in Grain Production:A Case Study of Changshu,Taihe and Ansai in China 被引量:6
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作者 SONG Wei CHEN Baiming CHEN Xiwei 《Chinese Geographical Science》 SCIE CSCD 2009年第1期46-54,共9页
This paper aims to establish an index system for evaluation of agricultural resources use efficiency(ARUE) in grain production and discuss the causes of low efficiency and high consumption of agricultural resources in... This paper aims to establish an index system for evaluation of agricultural resources use efficiency(ARUE) in grain production and discuss the causes of low efficiency and high consumption of agricultural resources in Changshu of Jiangsu Province,Taihe of Jiangxi Province and Ansai of Shaanxi Province in China by analyzing the data about meteorology,soil,water consumption and grain production. Agro-ecological Zone(AEZ) method was adopted to calculate the potential productivity,and synthetically multivariate equation was used to evaluate the ARUE of study areas. This paper can be concluded as:1) the agricultural resources in grain production can be classified into five categories,i.e.,climatic resources,water resources,land resources,biological resources and assistant resources,and 15 indexes were selected to evaluate their use efficiency in grain production;2) the values of ARUE in grain production are 0.5868,0.6368 and 0.5390 respectively in Changshu,Taihe and Ansai;and 3) Changshu ranks the highest among the three study areas in terms of the use efficiency of climatic resources and biological resources(evaluation values are 0.0277 and 0.1530) ,but Taihe tops the three in terms of the use efficiency of water resources,land resources and assistant resources(evaluation values are 0.0502,0.2945 and 0.1379 respectively) . However,the ARUE remains always low in Ansai for all the resources. The inefficiencies are caused by poor grain revenue in Changshu,deficient agriculture investments in Taihe and unfavorable natural conditions in Ansai. 展开更多
关键词 agricultural resources use efficiency grain production Changshu Taihe Ansai
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Determination of Threshold for Energy Detection in Cognitive Radio Sensor Networks 被引量:4
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作者 郝建军 黎晋 《China Communications》 SCIE CSCD 2011年第1期14-19,共6页
The Internet of Things (loT) is called the world' s third wave of the information industry. As the core technology of IoT, Cognitive Radio Sensor Networks (CRSN) technology can improve spectrum utilization effici... The Internet of Things (loT) is called the world' s third wave of the information industry. As the core technology of IoT, Cognitive Radio Sensor Networks (CRSN) technology can improve spectrum utilization efficiency and lay a sofid foundation for large-scale application of IoT. Reliable spectrum sensing is a crucial task of the CR. For energy de- tection, threshold will determine the probability of detection (Pd) and the probability of false alarm Pf at the same time. While the threshold increases, Pd and Pf will both decrease. In this paper we focus on the maximum of the difference of Pd and Pf, and try to find out how to determine the threshold with this precondition. Simulation results show that the proposed method can effectively approach the ideal optimal result. 展开更多
关键词 Internet of Sensor Networks energy Things Cognitive Radio detection THRESHOLD
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Impacts of climate change on agricultural water resources and adaptation on the North China Plain 被引量:7
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作者 MO Xing-Guo HU Shi +2 位作者 LIN Zhong-Hui LIU Su-Xia XIA Jun 《Advances in Climate Change Research》 SCIE CSCD 2017年第2期93-98,共6页
Climate change is having a considerable impact on the availability of water resources for agricultural production on the North China Plain (NCP), where the shortage of water is currently disturbing the stability and... Climate change is having a considerable impact on the availability of water resources for agricultural production on the North China Plain (NCP), where the shortage of water is currently disturbing the stability and sustainability of agricultural production with respect to the drying tendency since the 1950s. However, although potential evapotranspiration (ET) has shown a decreasing trend under climate change, actual ET has slightly increased with an acceleration in hydrological cycling. Global climate model (GCM) ensemble projections predict that by the 2050s, the increased crop water demand and intensified ET resulting from global warming will reduce water resources surplus (Precipitation-ET) about 4%-24% and increase significantly the irrigation water demand in crop growth periods. This study assesses possible mitigation and adaptation measures for enabling agricultural sustainability. It is revealed that reducing the sowing area of winter wheat (3.0%-15.9%) in water-limited basins, together with improvement in crop water-use efficiency would effectively mitigate water shortages and intensify the resilience of agricultural systems to climate change. 展开更多
关键词 Climate change Water resources AGRICULTURE Adaptation measures
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