In this paper,a prediction model on Chinese annual live hog supply was established.With cointegration test,backward and forward stochastic selection and other methods,four main factors(hog price,prices of inputs in ho...In this paper,a prediction model on Chinese annual live hog supply was established.With cointegration test,backward and forward stochastic selection and other methods,four main factors(hog price,prices of inputs in hog production,the level of hog inventory,as well as emergency and government policy) were chosen from 16 relevant factors to establish the model and make improvement.Applied the improved model,annual live hog supply in China from 2013 to 2016 was predicted in three scenarios.The predicted results showed that if there were no major emergencies from 2013 to 2016,there would be an upward trend in Chinese live hog supply year by year.The supply of live hogs in China in 2013 would be about 707.663 million head,in 2014 would be between 715.935 and 742.969 million head,in 2015 between 734.458 and 779.413 million head,and in 2016 between 750.923 and809.450 million head.展开更多
Based on the perspective of pig population system prediction,and accorded to principle of pig months transfer,this paper refers to the modeling principle and method of discrete population quantity prediction model.The...Based on the perspective of pig population system prediction,and accorded to principle of pig months transfer,this paper refers to the modeling principle and method of discrete population quantity prediction model.Then the prediction model of pork supply is derived and established:Firstly,the recursive model of pig population system and estimation model of pork supply was established.Then this study estimated the sum of monthly mortality and culling rate of breeding sows.Furthermore,the method for new left gilts in each month and estimation of breeding sows at each month of age was established.Last,this research established the estimation method model of the initial state of pig population.On this basis,an example calculation is made to predict the monthly pork supply in Heilongjiang Province from January 2016 to March 2018 in the future.The results showed that the prediction model of pork supply based on the prediction of pig population system is an effective perspective to study the forecast of pork supply.In the prediction stage,the prediction accuracy of the number of slaughtered fattened hogs was 96.36%and 97.54%,and the prediction accuracy of pork supply was 98.08%and 93.82%.This study not only lay a theoretical foundation for further study on the balance between pork supply and demand,but also helps to guide pork producers and governments at all levels to make relevant production decisions and plans.展开更多
Water resource allocation （WRA） is a useful but complicated topic in water resource management. With the targets set out in the Plan of Newly Increasing Yield （NIY） of 10×1011 Jin （1 kg=2 Jin） from 2009 to ...Water resource allocation （WRA） is a useful but complicated topic in water resource management. With the targets set out in the Plan of Newly Increasing Yield （NIY） of 10×1011 Jin （1 kg=2 Jin） from 2009 to 2020, the immediate question for the Songhua River Region （SHRR） is whether water is sufficient to support the required yield increase. Very few studies have considered to what degree this plan influences the solution of WRA and how to adapt. This paper used a multi-objective programming model for WRA across the Harbin region located in the SHRR in 2020 and 2030 （p=75%）. The Harbin region can be classified into four types of sub-regions according to WRA： Type I is Harbin city zone. With rapid urbanization, Harbin city zone has the highest risk of agricultural water shortage. Considering the severe situation, there is little space for Harbin city zone to reach the NIY goal. Type II is sub-regions including Wuchang, Shangzhi and Binxian. There are some agricultural water shortage risks in this type region. Because the water shortage is relatively small, it is possible to increase agricultural production through strengthening agricultural water-saving countermeasures and constructing water conservation facilities. Type III is sub-regions including Acheng, Hulan, Mulan and Fangzheng. In this type region, there may be a water shortage if the rate of urbanization accelerates. According to local conditions, it is needed to enhance water-saving countermeasures to increase agricultural production to a certain degree. Type IV is sub-regions including Shuangcheng, Bayan, Yilan, Yanshou and Tonghe. There are good water conditions for the extensive development of agriculture. Nevertheless, in order to ensure an increase in agricultural production, it is necessary to enhance the way in which water is utilized and consider soil resources. These results will help decision makers make a scientific NIY plan for the Harbin region for sustainable utilization of regional water resources and an increase in agricultural production.展开更多
基金supported by the National Key Technology R&D Program under Grant No.2009BADA 9BB01-4the National Natural Science Foundation of China under Grant Nos.71173210 and 61273208
文摘In this paper,a prediction model on Chinese annual live hog supply was established.With cointegration test,backward and forward stochastic selection and other methods,four main factors(hog price,prices of inputs in hog production,the level of hog inventory,as well as emergency and government policy) were chosen from 16 relevant factors to establish the model and make improvement.Applied the improved model,annual live hog supply in China from 2013 to 2016 was predicted in three scenarios.The predicted results showed that if there were no major emergencies from 2013 to 2016,there would be an upward trend in Chinese live hog supply year by year.The supply of live hogs in China in 2013 would be about 707.663 million head,in 2014 would be between 715.935 and 742.969 million head,in 2015 between 734.458 and 779.413 million head,and in 2016 between 750.923 and809.450 million head.
基金This research was supported by Heilongjiang Province Philosophy and Social Science Research Planning Project(18GLC205)(17GYB084)Heilongjiang Province Doctors Back Project(LBH-Z18024)Northeast Agricultural University Youth Talent Research Fund(18QC18).
文摘Based on the perspective of pig population system prediction,and accorded to principle of pig months transfer,this paper refers to the modeling principle and method of discrete population quantity prediction model.Then the prediction model of pork supply is derived and established:Firstly,the recursive model of pig population system and estimation model of pork supply was established.Then this study estimated the sum of monthly mortality and culling rate of breeding sows.Furthermore,the method for new left gilts in each month and estimation of breeding sows at each month of age was established.Last,this research established the estimation method model of the initial state of pig population.On this basis,an example calculation is made to predict the monthly pork supply in Heilongjiang Province from January 2016 to March 2018 in the future.The results showed that the prediction model of pork supply based on the prediction of pig population system is an effective perspective to study the forecast of pork supply.In the prediction stage,the prediction accuracy of the number of slaughtered fattened hogs was 96.36%and 97.54%,and the prediction accuracy of pork supply was 98.08%and 93.82%.This study not only lay a theoretical foundation for further study on the balance between pork supply and demand,but also helps to guide pork producers and governments at all levels to make relevant production decisions and plans.
基金the Knowledge Innovation Project of Chinese Academy of Sciences (NO.KZCX2-YW-Q06-1-3)the Ministry of Science and Technology of China for"973"project(NO.2010CB428404)
文摘Water resource allocation （WRA） is a useful but complicated topic in water resource management. With the targets set out in the Plan of Newly Increasing Yield （NIY） of 10×1011 Jin （1 kg=2 Jin） from 2009 to 2020, the immediate question for the Songhua River Region （SHRR） is whether water is sufficient to support the required yield increase. Very few studies have considered to what degree this plan influences the solution of WRA and how to adapt. This paper used a multi-objective programming model for WRA across the Harbin region located in the SHRR in 2020 and 2030 （p=75%）. The Harbin region can be classified into four types of sub-regions according to WRA： Type I is Harbin city zone. With rapid urbanization, Harbin city zone has the highest risk of agricultural water shortage. Considering the severe situation, there is little space for Harbin city zone to reach the NIY goal. Type II is sub-regions including Wuchang, Shangzhi and Binxian. There are some agricultural water shortage risks in this type region. Because the water shortage is relatively small, it is possible to increase agricultural production through strengthening agricultural water-saving countermeasures and constructing water conservation facilities. Type III is sub-regions including Acheng, Hulan, Mulan and Fangzheng. In this type region, there may be a water shortage if the rate of urbanization accelerates. According to local conditions, it is needed to enhance water-saving countermeasures to increase agricultural production to a certain degree. Type IV is sub-regions including Shuangcheng, Bayan, Yilan, Yanshou and Tonghe. There are good water conditions for the extensive development of agriculture. Nevertheless, in order to ensure an increase in agricultural production, it is necessary to enhance the way in which water is utilized and consider soil resources. These results will help decision makers make a scientific NIY plan for the Harbin region for sustainable utilization of regional water resources and an increase in agricultural production.
