Resource utilization efficiency is one of important factors influencing modern agricultural development. This paper evaluates agricultural resource utilization efficiency of Hebei Province in the Eleventh Five-Year Pl...Resource utilization efficiency is one of important factors influencing modern agricultural development. This paper evaluates agricultural resource utilization efficiency of Hebei Province in the Eleventh Five-Year Plan period by dynamic comprehensive evaluation method. Evaluation results indicate that regional disparity in agricultural resource utilization efficiency is significant, and the disparity is increasing year by year.展开更多
The utilization efficiency of resources is one of the important factors affecting the development of modern agriculture. Using production function method and ratio analysis method,we carry out the horizontal compariso...The utilization efficiency of resources is one of the important factors affecting the development of modern agriculture. Using production function method and ratio analysis method,we carry out the horizontal comparison of the utilization efficiency of major agricultural resources such as arable land,agricultural machinery power and chemical fertilizer in Hebei Province and the national level,and the vertical comparison of the utilization efficiency of major agricultural resources between the prefecture-level cities in the province. The results show that the utilization efficiency of agricultural resources in Hebei Province is below the national average,and there are significant differences in the utilization efficiency of agricultural resources between the prefecture-level cities in the province.展开更多
In order to pursue good crushing load uniformity and enchance energy absorption efficiency of conventional honeycombs, a kind of bio-inspired hierarchical honeycomb model is proposed by mimicking the arched crab shell...In order to pursue good crushing load uniformity and enchance energy absorption efficiency of conventional honeycombs, a kind of bio-inspired hierarchical honeycomb model is proposed by mimicking the arched crab shell structures. Three bio-inspired hierarchical honeycombs(BHHs) with different topologies are designed by replacing each vertex of square honeycombs with smaller arc-shaped structures. The effects of hierarchical topologies and multi-material layout on in-plane dynamic crushings and absorbed-energy capacities of the BHHs are explored based on the explicit finite element(FE) analysis.Different deformation modes can be observed from the BHHs, which mainly depend upon hierarchical topologies and impact velocities. According to energy efficiency method and one-dimensional(1D) shock theory, calculation formulas of densification strains and plateau stresses for the BHHs are derived to characterize the dynamic bearing capacity, which is consistent well with FE results. Compared with conventional honeycombs, the crushing load efficiency and energy absorption capacity of the BHHs can be improved by changing the proper hierarchical topology and multi-material layout. These researches will provide theoretical guidance for innovative design and dynamic response performance controllability of honeycombs.展开更多
Based on the introduction of the connotation of"lemon market"and the phenomenon of"lemon"in the market of agricultural products,the consumers'behaviors in the"lemon market"of agricult...Based on the introduction of the connotation of"lemon market"and the phenomenon of"lemon"in the market of agricultural products,the consumers'behaviors in the"lemon market"of agricultural products are analyzed.Firstly,consumers feel unfair in their minds in the process of negotiation;secondly,the purchase decision rule tends to be simplified in the"lemon market"of agricultural products;thirdly,the consumers tend to follow the masses in the"lemon market"of agricultural products.The economics significance of the impact of"lemon dilemma"of agricultural products on consumers is analyzed.The causes of the impact are analyzed from two aspects the uncertainty of collecting the information of agricultural information and the uncertainty of using the agricultural information.The suggestions and countermeasures are put forward in order to solve the"lemon"problems in agricultural market.In the first place,the excellent mechanism for producing the information of agricultural products should be constructed;in the second place,the government should encourage the multi-channel,multi-form and multi-level operation mode of agricultural products,to promote the optimization of market functions;in the third place,the government should widen the channel of information dissemination for agricultural products and establish the high efficiency feedback path;in the fourth place,the traditional thought pattern of consumers should be changed,so as to promote the healthy,orderly and benign development of agricultural products market.展开更多
Technical Barriers to Trade （TBT） have become an important obstacle to the export of Chinese agricultural products. The paper analyzes the connotation and the development trend of TBT, then analyzes the birth of TBT...Technical Barriers to Trade （TBT） have become an important obstacle to the export of Chinese agricultural products. The paper analyzes the connotation and the development trend of TBT, then analyzes the birth of TBT through using Game theory and explains the motives of the countries setting up TBT. Finally, the paper proposes countermeasures from two aspects of government and enterprises in China.展开更多
基金Supported by Hebei Province Philosophy and Social Science Planning Project in 2011(201102002)
文摘Resource utilization efficiency is one of important factors influencing modern agricultural development. This paper evaluates agricultural resource utilization efficiency of Hebei Province in the Eleventh Five-Year Plan period by dynamic comprehensive evaluation method. Evaluation results indicate that regional disparity in agricultural resource utilization efficiency is significant, and the disparity is increasing year by year.
文摘The utilization efficiency of resources is one of the important factors affecting the development of modern agriculture. Using production function method and ratio analysis method,we carry out the horizontal comparison of the utilization efficiency of major agricultural resources such as arable land,agricultural machinery power and chemical fertilizer in Hebei Province and the national level,and the vertical comparison of the utilization efficiency of major agricultural resources between the prefecture-level cities in the province. The results show that the utilization efficiency of agricultural resources in Hebei Province is below the national average,and there are significant differences in the utilization efficiency of agricultural resources between the prefecture-level cities in the province.
基金the financial support provided by the Natural Science Foundation of Hebei Province of China [No. A2020502005]the Fundamental Research Funds for the Central Universities [No. 2020MS113]Science & Technology Program of Baoding [No. 1911ZG019]。
文摘In order to pursue good crushing load uniformity and enchance energy absorption efficiency of conventional honeycombs, a kind of bio-inspired hierarchical honeycomb model is proposed by mimicking the arched crab shell structures. Three bio-inspired hierarchical honeycombs(BHHs) with different topologies are designed by replacing each vertex of square honeycombs with smaller arc-shaped structures. The effects of hierarchical topologies and multi-material layout on in-plane dynamic crushings and absorbed-energy capacities of the BHHs are explored based on the explicit finite element(FE) analysis.Different deformation modes can be observed from the BHHs, which mainly depend upon hierarchical topologies and impact velocities. According to energy efficiency method and one-dimensional(1D) shock theory, calculation formulas of densification strains and plateau stresses for the BHHs are derived to characterize the dynamic bearing capacity, which is consistent well with FE results. Compared with conventional honeycombs, the crushing load efficiency and energy absorption capacity of the BHHs can be improved by changing the proper hierarchical topology and multi-material layout. These researches will provide theoretical guidance for innovative design and dynamic response performance controllability of honeycombs.
文摘Based on the introduction of the connotation of"lemon market"and the phenomenon of"lemon"in the market of agricultural products,the consumers'behaviors in the"lemon market"of agricultural products are analyzed.Firstly,consumers feel unfair in their minds in the process of negotiation;secondly,the purchase decision rule tends to be simplified in the"lemon market"of agricultural products;thirdly,the consumers tend to follow the masses in the"lemon market"of agricultural products.The economics significance of the impact of"lemon dilemma"of agricultural products on consumers is analyzed.The causes of the impact are analyzed from two aspects the uncertainty of collecting the information of agricultural information and the uncertainty of using the agricultural information.The suggestions and countermeasures are put forward in order to solve the"lemon"problems in agricultural market.In the first place,the excellent mechanism for producing the information of agricultural products should be constructed;in the second place,the government should encourage the multi-channel,multi-form and multi-level operation mode of agricultural products,to promote the optimization of market functions;in the third place,the government should widen the channel of information dissemination for agricultural products and establish the high efficiency feedback path;in the fourth place,the traditional thought pattern of consumers should be changed,so as to promote the healthy,orderly and benign development of agricultural products market.
文摘Technical Barriers to Trade （TBT） have become an important obstacle to the export of Chinese agricultural products. The paper analyzes the connotation and the development trend of TBT, then analyzes the birth of TBT through using Game theory and explains the motives of the countries setting up TBT. Finally, the paper proposes countermeasures from two aspects of government and enterprises in China.
