The machine learning models of multiple linear regression(MLR),support vector regression(SVR),and extreme learning ma-chine(ELM)and the proposed ELM models of online sequential ELM(OS-ELM)and OS-ELM with forgetting me...The machine learning models of multiple linear regression(MLR),support vector regression(SVR),and extreme learning ma-chine(ELM)and the proposed ELM models of online sequential ELM(OS-ELM)and OS-ELM with forgetting mechanism(FOS-ELM)are applied in the prediction of the lime utilization ratio of dephosphorization in the basic oxygen furnace steelmaking process.The ELM model exhibites the best performance compared with the models of MLR and SVR.OS-ELM and FOS-ELM are applied for sequential learning and model updating.The optimal number of samples in validity term of the FOS-ELM model is determined to be 1500,with the smallest population mean absolute relative error(MARE)value of 0.058226 for the population.The variable importance analysis reveals lime weight,initial P content,and hot metal weight as the most important variables for the lime utilization ratio.The lime utilization ratio increases with the decrease in lime weight and the increases in the initial P content and hot metal weight.A prediction system based on FOS-ELM is applied in actual industrial production for one month.The hit ratios of the predicted lime utilization ratio in the error ranges of±1%,±3%,and±5%are 61.16%,90.63%,and 94.11%,respectively.The coefficient of determination,MARE,and root mean square error are 0.8670,0.06823,and 1.4265,respectively.The system exhibits desirable performance for applications in actual industrial pro-duction.展开更多
Reasonable distribution of braking force is a factor for a smooth,safe,and comfortable braking of trains.A dynamic optimal allocation strategy of electric-air braking force is proposed in this paper to solve the probl...Reasonable distribution of braking force is a factor for a smooth,safe,and comfortable braking of trains.A dynamic optimal allocation strategy of electric-air braking force is proposed in this paper to solve the problem of the lack of consideration of adhesion difference of train wheelsets in the existing high-speed train electric-air braking force optimal allocation strategies.In this method,the braking strategy gives priority to the use of electric braking force.The force model of a single train in the braking process is analyzed to calculate the change of adhesion between the wheel and rail of each wheelset after axle load transfer,and then the adhesion of the train is estimated in real time.Next,with the goal of maximizing the total adhesion utilization ratio of trailer/motor vehicles,a linear programming distribution function is constructed.The proportional coefficient of adhesion utilization ratio of each train and the application upper limit of braking force in the function is updated according to the change time point of wheelset adhesion.Finally,the braking force is dynamically allocated.The simulation results of Matlab/Simulink show that the proposed algorithm not only uses the different adhesion limits of each trailer to reduce the total amount of braking force undertaken by the motor vehicle,but also considers the adhesion difference of each wheelset.The strategy can effectively reduce the risk and time of motor vehicles during the braking process and improve the stability of the train braking.展开更多
A series of CexZr0.50-xAl0.50O1.75(0.05≤x≤0.45) mixed oxides with different Ce/Zr ratio were prepared by co-precipitation method and characterized by means of X-ray diffraction(XRD),Brunauer-Emmet Teller method(BET)...A series of CexZr0.50-xAl0.50O1.75(0.05≤x≤0.45) mixed oxides with different Ce/Zr ratio were prepared by co-precipitation method and characterized by means of X-ray diffraction(XRD),Brunauer-Emmet Teller method(BET),temperature-programmed reduction(H2-TPR) and oxygen pulsing technique.The XRD results showed that all samples kept the single CeO2 cubic fluorite structure after calcination at 600 and 1000 oC for 5 h.The results of BET revealed that CexZr0.50-xAl0.50O1.75 with Ce/Zr molar ratio 1/1 exhibited hi...展开更多
Based on the steady-state solution of finite-state birth and death process, the principle of line configuration for shared multi-channel system is analyzed. Call congestion ratio equation and channel utilization ratio...Based on the steady-state solution of finite-state birth and death process, the principle of line configuration for shared multi-channel system is analyzed. Call congestion ratio equation and channel utilization ratio equation are deduced, and visualized data analysis is presented. The analy-sis indicates that, calculated with the proposed equations, the overestimate for call congestion ratio and channel utilization ratio can be rectified, and thereby the cost of channels can be saved by 2000 in a small system.With MATLAB programming, line configuration methods are provided. In order to generally and intuitively show the dynamic running of the system, and to analyze,promote and improve it, the system is simulated using M/M/n/n/m queuing model and Monte-Carlo method. In addition, the simulation validates the correctness of the theoretical analysis and optimizing configuration method.展开更多
This paper studied the relationships between utilization ratios and conversion rates of nitrogen,phosphorus and potassium for maize by data mining method based on data of"3414 fertilizer field trials"of maiz...This paper studied the relationships between utilization ratios and conversion rates of nitrogen,phosphorus and potassium for maize by data mining method based on data of"3414 fertilizer field trials"of maize by published papers from national soil testing and recommendation since 2005.The results and conclusions were as follows:①the conceptual model of fertilizer utilization ratio of maize for plot was that,Y N≈a+b×optimum yield,Y P≈a+b×optimum yield-c×optimum nitrogen application amount-d×optimum potassium application amount,Y K≈a-b×optimum nitrogen application amount-c×temperature in growth season-d×rainfall in growth season,respectively.②Fertilizer utilization ratio and nutrient conversion rate had 4 kinds of relationships.No significant relationships:22,of which 16 were soil nutrients and 5 were environmental factors,the results showed that soil nutrients and environmental factors had little effect on nutrient conversion rate and fertilizer utilization ratio;consistent significant relationships:14,illustrating that conversion rate and utilization ratio of maize were consistent in most cases,and it was because that maize was planted for a long term,and its fertilizer absorption law was basically stable;contrary significant relationships:0,illustrating that there was no reverse relationship between conversion rate and utilization ratio of maize;complementary significant relationships:18,the cause of the complementary phenomenon was that the fertilizer utilization ratio was the measuring index of fertilizer efficiency in one season,while the nutrient conversion rate was the measuring index of fertilizer efficiency in more seasons.It showed that the fertilizer utilization ratio was significantly correlated,or the nutrient conversion rate was significantly correlated.展开更多
This paper studied the relationships between utilization ratios and conversion rates of nitrogen,phosphorus and potassium for wheat by data mining method based on data of"3414 fertilizer field trials"of whea...This paper studied the relationships between utilization ratios and conversion rates of nitrogen,phosphorus and potassium for wheat by data mining method based on data of"3414 fertilizer field trials"of wheat by published papers from national soil testing and recommendation since 2005.The results and conclusions were as follows:①the conceptual model of fertilizer utilization ratio of wheat for plot was that,Y N≈a+b×optimum nitrogen application amount+c×optimum fertilizer amount of K+d×rainfall in growth season,Y P≈a+b×optimum fertilizer amount of K+c×rainfall in growth season,Y K≈a+b×temperature in growth season+c×rainfall in growth season-d×optimum yield-e×optimum nitrogen application amount,respectively.②Fertilizer utilization ratio and nutrient conversion rate had 4 kinds of relationships.No significant relationships:13,of which 8 were soil nutrients,the results showed that soil nutrients had little effect on nutrient conversion rate and fertilizer utilization ratio;consistent significant relationships:4,they were all nitrogen and phosphorus,explaining the importance of nitrogen and phosphorus;contrary significant relationships:6,they were all nitrogen and phosphorus,illustrating that phosphorus and nitrogen had inhibitory effect;complementary significant relationships:31,the cause of the complementary phenomenon was that the fertilizer utilization ratio was the measuring index of fertilizer efficiency in one season,while the nutrient conversion rate was the measuring index of fertilizer efficiency in more seasons.It showed that the fertilizer utilization rate was significantly correlated,or the nutrient conversion rate was significantly correlated.展开更多
This paper studied the relationships between utilization ratios and conversion rates of nitrogen,phosphorus and potassium for rice by data mining method based on data of"3414 fertilizer field trials"of rice ...This paper studied the relationships between utilization ratios and conversion rates of nitrogen,phosphorus and potassium for rice by data mining method based on data of"3414 fertilizer field trials"of rice by published papers from national soil testing and recommendation since 2005.The results and conclusions were as follows:①the conceptual model of fertilizer utilization ratio of rice for plot was that,Y N≈a+b×optimum yield+c×optimum fertilizer amount of K,Y P≈a+b×optimum yield,Y K≈a respectively.②Fertilizer utilization ratio and nutrient conversion rate had 4 kinds of relationships:①no significant relationships:25,of which 14 were soil nutrients and 9 were environmental factors,the results showed that soil nutrients and environmental factors had little effect on nutrient yield ratio and fertilizer utilization ratio;②consistent significant relationships:2,one was that yield ratio and utilization ratio of N were positively correlated with the optimum production,explaining the importance of N for production,the other was that yield ratio and utilization ratio of P had a significantly positive correlation with conversion rate and utilization ratio of N,illustrating that nitrogen and phosphorus had mutual promotion;③contrary significant relationships:5,these showed as negative correlations of fertilizer utilization ratio and positive correlation of nutrient conversion ratio;④complementary significant relationships:22,the cause of the complementary phenomenon was that the fertilizer utilization ratio was the index of fertilizer efficiency in one season,while the nutrient conversion rate was the index of fertilizer efficiency in more seasons,which showed that the fertilizer utilization rate was significantly correlated,or the nutrient conversion rate was significantly correlated.展开更多
Secure storage yard is one of the optimal core goals of container transportation;thus,making the necessary storage arrangements has become the most crucial part of the container terminal management systems（CTMS）.Thi...Secure storage yard is one of the optimal core goals of container transportation;thus,making the necessary storage arrangements has become the most crucial part of the container terminal management systems（CTMS）.This paper investigates a random hybrid stacking algorithm（RHSA） for outbound containers that randomly enter the yard.In the first stage of RHSA,the distribution among blocks was analyzed with respect to the utilization ratio.In the second stage,the optimization of bay configuration was carried out by using the hybrid genetic algorithm.Moreover,an experiment was performed to test the RHSA.The results show that the explored algorithm is useful to increase the efficiency.展开更多
Internal reformation of low steam methane fuel is highly beneficial for improving the energy efficiency and reducing the system complexity and cost of solid oxide fuel cells(SOFCs).However,anode coking for the Ni-base...Internal reformation of low steam methane fuel is highly beneficial for improving the energy efficiency and reducing the system complexity and cost of solid oxide fuel cells(SOFCs).However,anode coking for the Ni-based anode should be prevented before the technology becomes a reality.A multi-physics fully coupled model is employed to simulate the operations of SOFCs fueled by low steam methane.The multi-physics model produces I-V relations that are in excellent agreement with the experimental results.The multi-physics model and the experimental non-coking current density deduced kinetic carbon activity criterion are used to examine the effect of operating parameters and the anode diffusion barrier layer on the propensity of carbon deposition.The interplays among the fuel utilization ratio,current generation,thickness of the barrier layer and the cell operating voltage are revealed.It is demonstrated that a barrier layer of 400μm thickness is an optimal and safe anode design to achieve high power density and non-coking operations.The anode structure design can be very useful for the development of high efficiency and low cost SOFC technology.展开更多
A pot experiment combined with15N isotope techniques was conducted to evaluate effects of the varying rates of urea-N fertilizer application on yields,quality,and nitrogen use efficiency (NUE) of pakchoi cabbage (Bras...A pot experiment combined with15N isotope techniques was conducted to evaluate effects of the varying rates of urea-N fertilizer application on yields,quality,and nitrogen use efficiency (NUE) of pakchoi cabbage (Brassica chinensis L.) and asparagus lettuce (Lactuca saiva L.).15N-labbled urea (5.3515N atom %) was added to pots with 6.5 kg soil of 0.14,0.18,0.21,0.25,and 0.29 g N/kg soil,and applied in two splits:60 percent as basal dressing in the mixture and 40 percent as topdressing.The fresh yields of two vegetable species increased with the increasing input of urea-N,but there was a significant quadratic relationship between the dose of urea-N fertilizer application and the fresh yields.When the dosage of urea-N fertilizer reached a certain value,nitrate readily accumulated in the two kinds of plants due to the decrease in NR activity; furthermore,there was a linear negative correlation between nitrate content and NR activity.With the increasing input of urea-N,ascorbic acid and soluble sugar initially increased,declined after a while,and crude fiber rapidly decreased too.Total absorbed N (TAN),N derived from fertilizer (Ndff),and N derived from soil (Ndfs) increased,and the ratio of Ndff and TAN also increased,but the ratio of Ndfs and TAN as well as NUE of urea-N fertilizer decreased with the increasing input of urea-N.These results suggested that the increasing application of labeled N fertilizer led to the increase in unlabeled N (namely,Ndfs) presumably due to "added nitrogen interaction" (ANI),the decease in NUE of urea-N fertilizer may be due to excess fertilization beyond the levels of plant requirements and the ANI,and the decrease in the two vegetable yields with the increasing addition of urea-N possibly because the excess accumulation of nitrate reached a toxic level.展开更多
In order to study the major performance indicators of the twin-rotor piston engine(TRPE), Matlab/simulink was used to simulate the mathematical models of its thermodynamic processes. With consideration of the characte...In order to study the major performance indicators of the twin-rotor piston engine(TRPE), Matlab/simulink was used to simulate the mathematical models of its thermodynamic processes. With consideration of the characteristics of the working processes in the TRPE, corresponding differential equations were established and then simplified by period features of the TRPE. Finally, the major boundary conditions were figured out. The changing trends of mass, pressure and temperature of working fuel in the working chamber during a complete engine cycle were presented. The simulation results are consistent with the trends of an actual working cycle in the TRPE, which indicates that the method of simulation is feasible. As the pressure in the working chamber is calculated, all the performance parameters of the TRPE can be obtained. The major performance indicators, such as the indicated mean effective pressure, power to weight ratio and the volume power, are also acquired. Compared with three different types of conventional engines, the TRPE has a bigger utilization ratio of cylinder volume, a higher power to weight ratio and a more compact structure. This indicates that TRPE is superior to conventional engines.展开更多
This paper conducted comparative study of the index system of ecological balanced fertilization for rice,wheat and maize by data mining method based on data of"3414 fertilizer field trials"of rice,wheat and ...This paper conducted comparative study of the index system of ecological balanced fertilization for rice,wheat and maize by data mining method based on data of"3414 fertilizer field trials"of rice,wheat and maize by published papers from national soil testing and recommendation since 2005.The main conclusions of this paper were as follow:①since the three crops all belonged to Gramineae,they were consistent in variation trends of fertilizer utilization ratio,nutrient conversion rate,relative abundance-deficiency value of soil nutrient,optimum fertilization amount in most cases.②Due to the influence of the economic production,biological production,different water conditions in paddy field and dry farmland,length of growing season,cropping system(one year before and after the rotation)and so on,sometimes the laws of four aspects above mentioned for the three crops had opposite and gradient variations.展开更多
This paper studied the index system of ecological balanced fertilization for three crops by data mining method based on data of"3414 fertilizer field trials"of rice,wheat and maize by published papers from n...This paper studied the index system of ecological balanced fertilization for three crops by data mining method based on data of"3414 fertilizer field trials"of rice,wheat and maize by published papers from national soil testing and recommendation since 2005.A systematic analysis of the materials and methods,the main research contents,the main research results and the main research conclusions of the column was made,in order to enable readers to understand and grasp the overall contents of the following 15 papers.展开更多
This paper studied the index system of ecological balanced fertilization for wheat by data mining method based on data of"3414 fertilizer field trials"of wheat by published papers from national soil testing ...This paper studied the index system of ecological balanced fertilization for wheat by data mining method based on data of"3414 fertilizer field trials"of wheat by published papers from national soil testing and recommendation since 2005.The results and conclusions were as follows.①Soil nutrient content could not be used as indicator of fertilizer application of wheat.②The conceptual model of N utilization ratio of wheat for plot was Y N≈a+b×optimum production-c×optimum fertilizer amount of N-d×temperature in growing season-e×rainfall in growing season,and the conceptual model of P conversion rate was Y P≈a+b×optimum production+c×temperature in growing season+d×precipitation in growing season-e×optimum fertilizer amount of P-f×optimum fertilizer amount of K,and the conceptual model of K conversion rate of wheat plots was that,Y K≈a-b×optimum fertilizer amount of K.③The conceptual model of the optimum fertilizer amount of N of wheat for plot was Y N≈a+b×optimum production+c×optimum fertilizer amount of P-d×temperature in growing season-e×rainfall in growing season,and the conceptual model of the optimum fertilizer amount of P was Y P≈a+b×optimum production+c×optimum fertilizer amount of N+d×optimum fertilizer amount of K,and the conceptual model of the optimum fertilizer amount of K was Y K≈a+b×optimum fertilizer amount of P.④The conceptual model of relative abundance-deficiency value of soil N of wheat for plot was that Y N≈a-b×temperature in growing season-c×precipitation in growing season,and the conceptual model of relative abundance-deficiency value of soil P was Y P≈a+b×optimum yield+c×optimum fertilizer amount of N+d×precipitation in growing season-e×optimum fertilizer amount of K,and the conceptual model of relative abundance-deficiency value of soil K was Y K≈a+b×optimum yield+c×optimum fertilizer amount of K.展开更多
This paper studied the index system of ecological balanced fertilization for wheat by data mining method based on data of"3414 fertilizer field trials"of wheat by published papers from national soil testing ...This paper studied the index system of ecological balanced fertilization for wheat by data mining method based on data of"3414 fertilizer field trials"of wheat by published papers from national soil testing and recommendation since 2005.The results and conclusions were as follows:①the optimum N,P and K fertilization amounts of wheat were within the normal range,and the application of this standard could not cause obvious non-point source pollution.②The conversion rates of N,P and K of wheat were 58.78%,58.63%and 199.88%higher than the utilization ratios of N,P and K under the optimum fertilization amount,respectively.③At present,the soil N for wheat was in a low equilibrium stage,and soil P and K were in the middle and high levels,in which P was in the accumulation stage,and K was in the depletion stage.④The relationship between fertilizer effect or fertility and optimum production had consistency.The fertilizer effect was negatively correlated with the optimum fertilization amounts of its own nutrient and other nutrients.N,P and K fertilizers had mutual promoting effects when they were balanced.Soil nutrient played an inhibitory role in the fertilizer efficiency of its own nutrient.⑤The phosphorus and potassium utilization ratios were significantly positively correlated with the optimum phosphorus fertilization amount and the optimal potassium fertilization amount,which was the scientific basis for phosphorus and potassium concentrated fertilization of wheat.展开更多
This paper studied the nitrogen index system of ecological balanced fertilization for rice by data mining method based on data of"3414 fertilizer field trials"of rice by published papers from national soil t...This paper studied the nitrogen index system of ecological balanced fertilization for rice by data mining method based on data of"3414 fertilizer field trials"of rice by published papers from national soil testing and recommendation since 2005.The results and conclusions were as follows.①Soil nutrient content could not be used as fertilization indicator of rice.②The conceptual model of nitrogen conversion rate of rice for plot was Y N≈a+b×optimum production-c×optimum nitrogen fertilization amount-d×optimum phosphorus fertilization amount,and the conceptual model of phosphorus conversion rate was Y P≈a-b×optimum phosphorus fertilization amount-c×optimum potassium fertilization amount,and the conceptual model of potassium conversion rate was Y K≈a+b×optimum production+c×optimum nitrogen fertilization amount-d×optimum potassium fertilization amount-e×annual average precipitation.③The conceptual model of the optimum nitrogen fertilization amount of rice for plot was Y N≈a+b×optimum production+c×optimum phosphorus fertilization amount-d×annual average precipitation,and the conceptual model of the optimum phosphorus fertilization amount was Y P≈a+b×optimum nitrogen fertilization amount+c×optimum potassium fertilization amount,and the conceptual model of the optimum potassium fertilization amount was Y K≈a+b×optimum phosphorus fertilization amount+c×annual average precipitation.④The conceptual model of relative abundance-deficiency value of soil nitrogen of rice for plot was Y N≈a-b×optimum nitrogen fertilization amount-c×optimum potassium fertilization amount,and the conceptual model of relative abundance-deficiency value of soil phosphorus was Y P≈a+b×soil available potassium-c×optimum potassium fertilization amount,and the conceptual model of relative abundance-deficiency value of soil potassium of rice was Y K≈a-b×optimum potassium fertilization amount.展开更多
This paper studied the index system of ecological balanced fertilization for maize by data mining method based on data of"3414 fertilizer field trials"of maize by published papers from national soil testing ...This paper studied the index system of ecological balanced fertilization for maize by data mining method based on data of"3414 fertilizer field trials"of maize by published papers from national soil testing and recommendation since 2005.The results and conclusions were as follows.①Soil nutrient content could not be used as indicator of fertilizer application of maize.②The conceptual model of N conversion rate of maize for plot was Y N≈a+b×optimum production-c×optimum fertilizer amount of N-d×optimum phosphorus application amount-e×optimum potassium application amount-f×temperature in growth season-g×rainfall in growth season.The conceptual model of P conversion rate of maize for plot was Y P≈a+b×optimum phosphorus application amount-c×optimum nitrogen application amount-d×optimum potassium application amount.The conceptual model of K conversion rate of maize for plot was Y K≈a+b×optimum yield-c×optimum nitrogen application amount-d×optimum phosphorus application amount-e×optimum potassium application amount-f×temperature in growth season-g×rainfall in growth season.③The conceptual model of the optimum fertilizer amount of N of maize for plot was Y N≈a+b×optimum phosphorus application amount+c×optimum potassium application amount+d×temperature in growing season+e×rainfall in growing season,and the conceptual model of the optimum fertilizer amount of P was Y P≈a+b×optimum nitrogen application amount,and the conceptual model of the optimum fertilizer amount of K was Y K≈a+b×optimum nitrogen application amount+c×temperature in growth season+d×rainfall in growth season-e×optimum yield.④The conceptual model of relative abundance-deficiency value of soil N of maize for plot was that Y N≈a,and the conceptual model of relative abundance-deficiency value of soil P was Y P≈a,and the conceptual model of relative abundance-deficiency value of soil K was Y K≈a+b×optimum nitrogen application amount+c×optimum phosphorus application amount.展开更多
In this paper,the index system of ecological balanced fertilization for wheat was discussed by data mining method based on this column.Three aspects of provincial average,typical province and all samples were studied,...In this paper,the index system of ecological balanced fertilization for wheat was discussed by data mining method based on this column.Three aspects of provincial average,typical province and all samples were studied,the results and conclusions were as follows:①climate condition was one of the main factors of soil formation,which was also an important basis for the division of wheat producing areas.The proportion of available nutrients was different in different wheat producing areas.This was the result of long-term climate and man-made action,and it constituted the basic fertility pattern of soil available nutrient for wheat in China.②One of the basic fertility indexes of soil for wheat in China was the proportion of available nutrients,which was the theoretical basis for adjusting the proportion of N,P and K fertilizers.③Although the total amount and proportion of available nutrients in different wheat producing areas were different,they can be adjusted to the optimum absorption ratio of wheat by fertilizing measures,so as to achieve the goal of ecological balanced fertilization such as high production and good quality.④The basic soil nutrient indexes of more than 5000 kg/hm 2 of wheat production were less than 6 of hydrolysable N/available P and less than 7 of available K/available P,and the fertilization index was that optimum K fertilization amount was 0.6-1.2 times of optimum P fertilization amount.展开更多
This paper studied the index system of ecological balanced fertilization for maize by data mining method based on data of"3414 fertilizer field trials"of maize by published papers from national soil testing ...This paper studied the index system of ecological balanced fertilization for maize by data mining method based on data of"3414 fertilizer field trials"of maize by published papers from national soil testing and recommendation since 2005.The results and conclusions were as follows:①the optimum N,P and K fertilization amounts of maize were within the normal range,and the application of this standard could not cause obvious non-point source pollution.②The conversion rates of N,P and K of maize were respectively higher than their respective utilization ratios under the optimum fertilization amount.③At present,the soil N for maize was in an absence state,and soil P and K were in a state of not obvious lack.④Optimum N,P and K fertilization amounts were significantly negatively correlated with their respective conversion ratios,respectively,and it provided a quantitative scientific basis for calculating the optimum fertilization amount according to the nutrient conversion rate.Each province can use this significant relationship to guide the determination of the average optimal fertilization amounts of N,P and K and the optimal production in the province.⑤The research results of nutrient conversion rate showed that any excessive application of N,P and K would reduce their own nutrient conversion rates,and may also reduce the conversion rates of other nutrients.The characteristics of crops absorbing N,P and K proportionally required that soil nutrients must be balanced in order to obtain high production,and fertilization was only the main means to regulate soil nutrient balance.展开更多
This paper studied the index system of ecological balanced fertilization for rice by data mining method based on data of"3414 fertilizer field trials"of rice by published papers from national soil testing an...This paper studied the index system of ecological balanced fertilization for rice by data mining method based on data of"3414 fertilizer field trials"of rice by published papers from national soil testing and recommendation since 2005.The results and conclusions were as follows:①the optimum N,P and K fertilization amounts of rice were within the normal range,and the application of this standard could not cause obvious non-point source pollution.②N,P and K conversion ratios were 76.4%,166.58%and 261.89%higher than N,P and K utilization ratios under the optimum fertilizer amount of rice,respectively.③At present,the soil N for rice was in a low equilibrium stage,and soil P and K were in the middle and high level,in which P was in the accumulation stage,while K was in the depletion stage.④The relationship between fertilizer effect or fertility and optimum production had consistency.The fertilizer effect was negatively correlated with the optimum fertilization amount of its own nutrient.N,P and K fertilizers had mutual promoting effect when they were balanced.Soil nutrient played an inhibitory role in the fertilizer efficiency of its own nutrient.Soil nutrient sometimes played a role in promoting the efficiency of other nutrients,and sometimes inhibited them.It was a positive correlation between soil nutrients with the same attribute.展开更多
基金supported by the National Natural Science Foundation of China (No.U1960202).
文摘The machine learning models of multiple linear regression(MLR),support vector regression(SVR),and extreme learning ma-chine(ELM)and the proposed ELM models of online sequential ELM(OS-ELM)and OS-ELM with forgetting mechanism(FOS-ELM)are applied in the prediction of the lime utilization ratio of dephosphorization in the basic oxygen furnace steelmaking process.The ELM model exhibites the best performance compared with the models of MLR and SVR.OS-ELM and FOS-ELM are applied for sequential learning and model updating.The optimal number of samples in validity term of the FOS-ELM model is determined to be 1500,with the smallest population mean absolute relative error(MARE)value of 0.058226 for the population.The variable importance analysis reveals lime weight,initial P content,and hot metal weight as the most important variables for the lime utilization ratio.The lime utilization ratio increases with the decrease in lime weight and the increases in the initial P content and hot metal weight.A prediction system based on FOS-ELM is applied in actual industrial production for one month.The hit ratios of the predicted lime utilization ratio in the error ranges of±1%,±3%,and±5%are 61.16%,90.63%,and 94.11%,respectively.The coefficient of determination,MARE,and root mean square error are 0.8670,0.06823,and 1.4265,respectively.The system exhibits desirable performance for applications in actual industrial pro-duction.
基金supported by the National Natural Science Foundation of China(Grant Nos.62173137,52172403,62303178).
文摘Reasonable distribution of braking force is a factor for a smooth,safe,and comfortable braking of trains.A dynamic optimal allocation strategy of electric-air braking force is proposed in this paper to solve the problem of the lack of consideration of adhesion difference of train wheelsets in the existing high-speed train electric-air braking force optimal allocation strategies.In this method,the braking strategy gives priority to the use of electric braking force.The force model of a single train in the braking process is analyzed to calculate the change of adhesion between the wheel and rail of each wheelset after axle load transfer,and then the adhesion of the train is estimated in real time.Next,with the goal of maximizing the total adhesion utilization ratio of trailer/motor vehicles,a linear programming distribution function is constructed.The proportional coefficient of adhesion utilization ratio of each train and the application upper limit of braking force in the function is updated according to the change time point of wheelset adhesion.Finally,the braking force is dynamically allocated.The simulation results of Matlab/Simulink show that the proposed algorithm not only uses the different adhesion limits of each trailer to reduce the total amount of braking force undertaken by the motor vehicle,but also considers the adhesion difference of each wheelset.The strategy can effectively reduce the risk and time of motor vehicles during the braking process and improve the stability of the train braking.
基金supported by the National Natural Science Foundation of China (20773090, 20803049)the National High Technology Research and Development Program of China (863 Program,2006AA06Z347)the Specialized Research Fund for the Doctoral Program of Higher Education (20070610026)
文摘A series of CexZr0.50-xAl0.50O1.75(0.05≤x≤0.45) mixed oxides with different Ce/Zr ratio were prepared by co-precipitation method and characterized by means of X-ray diffraction(XRD),Brunauer-Emmet Teller method(BET),temperature-programmed reduction(H2-TPR) and oxygen pulsing technique.The XRD results showed that all samples kept the single CeO2 cubic fluorite structure after calcination at 600 and 1000 oC for 5 h.The results of BET revealed that CexZr0.50-xAl0.50O1.75 with Ce/Zr molar ratio 1/1 exhibited hi...
文摘Based on the steady-state solution of finite-state birth and death process, the principle of line configuration for shared multi-channel system is analyzed. Call congestion ratio equation and channel utilization ratio equation are deduced, and visualized data analysis is presented. The analy-sis indicates that, calculated with the proposed equations, the overestimate for call congestion ratio and channel utilization ratio can be rectified, and thereby the cost of channels can be saved by 2000 in a small system.With MATLAB programming, line configuration methods are provided. In order to generally and intuitively show the dynamic running of the system, and to analyze,promote and improve it, the system is simulated using M/M/n/n/m queuing model and Monte-Carlo method. In addition, the simulation validates the correctness of the theoretical analysis and optimizing configuration method.
基金Collaborative Innovation Task of Science and Technology Innovation Project of Chinese Academy of Agricultural Sciences—Integration and Demonstration of Green and Efficient Agricultural Technology Innovation in Danjiangkou Water Conservation Area(CAAS-XTCX2016015)Major Scientific and Technological Projects in Guangxi(GUIKE AA17204077)+2 种基金Special Project of Guangxi Science and Technology Base and Talent(GUIKE AD18126012)First-class Discipline(Geography)Construction Project in GuangxiSpecial Funds for"Guangxi Bagui Scholars".
文摘This paper studied the relationships between utilization ratios and conversion rates of nitrogen,phosphorus and potassium for maize by data mining method based on data of"3414 fertilizer field trials"of maize by published papers from national soil testing and recommendation since 2005.The results and conclusions were as follows:①the conceptual model of fertilizer utilization ratio of maize for plot was that,Y N≈a+b×optimum yield,Y P≈a+b×optimum yield-c×optimum nitrogen application amount-d×optimum potassium application amount,Y K≈a-b×optimum nitrogen application amount-c×temperature in growth season-d×rainfall in growth season,respectively.②Fertilizer utilization ratio and nutrient conversion rate had 4 kinds of relationships.No significant relationships:22,of which 16 were soil nutrients and 5 were environmental factors,the results showed that soil nutrients and environmental factors had little effect on nutrient conversion rate and fertilizer utilization ratio;consistent significant relationships:14,illustrating that conversion rate and utilization ratio of maize were consistent in most cases,and it was because that maize was planted for a long term,and its fertilizer absorption law was basically stable;contrary significant relationships:0,illustrating that there was no reverse relationship between conversion rate and utilization ratio of maize;complementary significant relationships:18,the cause of the complementary phenomenon was that the fertilizer utilization ratio was the measuring index of fertilizer efficiency in one season,while the nutrient conversion rate was the measuring index of fertilizer efficiency in more seasons.It showed that the fertilizer utilization ratio was significantly correlated,or the nutrient conversion rate was significantly correlated.
基金Collaborative Innovation Task of Science and Technology Innovation Project of Chinese Academy of Agricultural Sciences—Integration and Demonstration of Green and Efficient Agricultural Technology Innovation in Danjiangkou Water Conservation Area(CAAS-XTCX2016015)Major Scientific and Technological Projects in Guangxi(GUIKE AA17204077)+2 种基金Special Project of Guangxi Science and Technology Base and Talent(GUIKE AD18126012)First-class Discipline(Geography)Construction Project in GuangxiSpecial Funds for"Guangxi Bagui Scholars".
文摘This paper studied the relationships between utilization ratios and conversion rates of nitrogen,phosphorus and potassium for wheat by data mining method based on data of"3414 fertilizer field trials"of wheat by published papers from national soil testing and recommendation since 2005.The results and conclusions were as follows:①the conceptual model of fertilizer utilization ratio of wheat for plot was that,Y N≈a+b×optimum nitrogen application amount+c×optimum fertilizer amount of K+d×rainfall in growth season,Y P≈a+b×optimum fertilizer amount of K+c×rainfall in growth season,Y K≈a+b×temperature in growth season+c×rainfall in growth season-d×optimum yield-e×optimum nitrogen application amount,respectively.②Fertilizer utilization ratio and nutrient conversion rate had 4 kinds of relationships.No significant relationships:13,of which 8 were soil nutrients,the results showed that soil nutrients had little effect on nutrient conversion rate and fertilizer utilization ratio;consistent significant relationships:4,they were all nitrogen and phosphorus,explaining the importance of nitrogen and phosphorus;contrary significant relationships:6,they were all nitrogen and phosphorus,illustrating that phosphorus and nitrogen had inhibitory effect;complementary significant relationships:31,the cause of the complementary phenomenon was that the fertilizer utilization ratio was the measuring index of fertilizer efficiency in one season,while the nutrient conversion rate was the measuring index of fertilizer efficiency in more seasons.It showed that the fertilizer utilization rate was significantly correlated,or the nutrient conversion rate was significantly correlated.
基金Major Scientific and Technological Projects in Guangxi(GUIKE AA17204077)Special Project of Guangxi Science and Technology Base and Talent(GUIKE AD18126012)+2 种基金First-class Discipline(Geography)Construction Project in GuangxiSpecial Funds for"Guangxi Bagui Scholars"Collaborative Innovation Task of Science and Technology Innovation Project of Chinese Academy of Agricultural Sciences—Integration and Demonstration of Green and Efficient Agricultural Technology Innovation in Danjiangkou Water Conservation Area(CAAS-XTCX2016015).
文摘This paper studied the relationships between utilization ratios and conversion rates of nitrogen,phosphorus and potassium for rice by data mining method based on data of"3414 fertilizer field trials"of rice by published papers from national soil testing and recommendation since 2005.The results and conclusions were as follows:①the conceptual model of fertilizer utilization ratio of rice for plot was that,Y N≈a+b×optimum yield+c×optimum fertilizer amount of K,Y P≈a+b×optimum yield,Y K≈a respectively.②Fertilizer utilization ratio and nutrient conversion rate had 4 kinds of relationships:①no significant relationships:25,of which 14 were soil nutrients and 9 were environmental factors,the results showed that soil nutrients and environmental factors had little effect on nutrient yield ratio and fertilizer utilization ratio;②consistent significant relationships:2,one was that yield ratio and utilization ratio of N were positively correlated with the optimum production,explaining the importance of N for production,the other was that yield ratio and utilization ratio of P had a significantly positive correlation with conversion rate and utilization ratio of N,illustrating that nitrogen and phosphorus had mutual promotion;③contrary significant relationships:5,these showed as negative correlations of fertilizer utilization ratio and positive correlation of nutrient conversion ratio;④complementary significant relationships:22,the cause of the complementary phenomenon was that the fertilizer utilization ratio was the index of fertilizer efficiency in one season,while the nutrient conversion rate was the index of fertilizer efficiency in more seasons,which showed that the fertilizer utilization rate was significantly correlated,or the nutrient conversion rate was significantly correlated.
基金Supported by the Research Grants from Shanghai Municipal Natural Science Foundation（No.10190502500） Shanghai Maritime University Start-up Funds,Shanghai Science＆Technology Commission Projects（No.09DZ2250400） Shanghai Education Commission Project（No.J50604）
文摘Secure storage yard is one of the optimal core goals of container transportation;thus,making the necessary storage arrangements has become the most crucial part of the container terminal management systems（CTMS）.This paper investigates a random hybrid stacking algorithm（RHSA） for outbound containers that randomly enter the yard.In the first stage of RHSA,the distribution among blocks was analyzed with respect to the utilization ratio.In the second stage,the optimization of bay configuration was carried out by using the hybrid genetic algorithm.Moreover,an experiment was performed to test the RHSA.The results show that the explored algorithm is useful to increase the efficiency.
基金supported by the National Natural Science Foundation of China (No.11574284 abd No.11774324)the National Basic Research Program of China (No.2012CB215405)Collaborative Innovation Center of Suzhou Nano Science and Technology
文摘Internal reformation of low steam methane fuel is highly beneficial for improving the energy efficiency and reducing the system complexity and cost of solid oxide fuel cells(SOFCs).However,anode coking for the Ni-based anode should be prevented before the technology becomes a reality.A multi-physics fully coupled model is employed to simulate the operations of SOFCs fueled by low steam methane.The multi-physics model produces I-V relations that are in excellent agreement with the experimental results.The multi-physics model and the experimental non-coking current density deduced kinetic carbon activity criterion are used to examine the effect of operating parameters and the anode diffusion barrier layer on the propensity of carbon deposition.The interplays among the fuel utilization ratio,current generation,thickness of the barrier layer and the cell operating voltage are revealed.It is demonstrated that a barrier layer of 400μm thickness is an optimal and safe anode design to achieve high power density and non-coking operations.The anode structure design can be very useful for the development of high efficiency and low cost SOFC technology.
基金Supported by International Plant Nutrition Institute (IPNI China Program: Hunan-11 )Hunan Provincial Key Subject ( Grant No.04NK2006)
文摘A pot experiment combined with15N isotope techniques was conducted to evaluate effects of the varying rates of urea-N fertilizer application on yields,quality,and nitrogen use efficiency (NUE) of pakchoi cabbage (Brassica chinensis L.) and asparagus lettuce (Lactuca saiva L.).15N-labbled urea (5.3515N atom %) was added to pots with 6.5 kg soil of 0.14,0.18,0.21,0.25,and 0.29 g N/kg soil,and applied in two splits:60 percent as basal dressing in the mixture and 40 percent as topdressing.The fresh yields of two vegetable species increased with the increasing input of urea-N,but there was a significant quadratic relationship between the dose of urea-N fertilizer application and the fresh yields.When the dosage of urea-N fertilizer reached a certain value,nitrate readily accumulated in the two kinds of plants due to the decrease in NR activity; furthermore,there was a linear negative correlation between nitrate content and NR activity.With the increasing input of urea-N,ascorbic acid and soluble sugar initially increased,declined after a while,and crude fiber rapidly decreased too.Total absorbed N (TAN),N derived from fertilizer (Ndff),and N derived from soil (Ndfs) increased,and the ratio of Ndff and TAN also increased,but the ratio of Ndfs and TAN as well as NUE of urea-N fertilizer decreased with the increasing input of urea-N.These results suggested that the increasing application of labeled N fertilizer led to the increase in unlabeled N (namely,Ndfs) presumably due to "added nitrogen interaction" (ANI),the decease in NUE of urea-N fertilizer may be due to excess fertilization beyond the levels of plant requirements and the ANI,and the decrease in the two vegetable yields with the increasing addition of urea-N possibly because the excess accumulation of nitrate reached a toxic level.
基金Project(7131109)supported by the National Defense Pre-research Foundation of ChinaProject(51175500)supported by the National Natural Science Foundation of China
文摘In order to study the major performance indicators of the twin-rotor piston engine(TRPE), Matlab/simulink was used to simulate the mathematical models of its thermodynamic processes. With consideration of the characteristics of the working processes in the TRPE, corresponding differential equations were established and then simplified by period features of the TRPE. Finally, the major boundary conditions were figured out. The changing trends of mass, pressure and temperature of working fuel in the working chamber during a complete engine cycle were presented. The simulation results are consistent with the trends of an actual working cycle in the TRPE, which indicates that the method of simulation is feasible. As the pressure in the working chamber is calculated, all the performance parameters of the TRPE can be obtained. The major performance indicators, such as the indicated mean effective pressure, power to weight ratio and the volume power, are also acquired. Compared with three different types of conventional engines, the TRPE has a bigger utilization ratio of cylinder volume, a higher power to weight ratio and a more compact structure. This indicates that TRPE is superior to conventional engines.
基金Major Scientific and Technological Projects in Guangxi(GUIKE AA17204077)Special Project of Guangxi Science and Technology Base and Talent(GUIKE AD18126012)+2 种基金First-class Discipline(Geography)Construction Project in GuangxiSpecial Funds for"Guangxi Bagui Scholars"Collaborative Innovation Task of Science and Technology Innovation Project of Chinese Academy of Agricultural Sciences—Integration and Demonstration of Green and Efficient Agricultural Technology Innovation in Danjiangkou Water Conservation Area(CAAS-XTCX2016015).
文摘This paper conducted comparative study of the index system of ecological balanced fertilization for rice,wheat and maize by data mining method based on data of"3414 fertilizer field trials"of rice,wheat and maize by published papers from national soil testing and recommendation since 2005.The main conclusions of this paper were as follow:①since the three crops all belonged to Gramineae,they were consistent in variation trends of fertilizer utilization ratio,nutrient conversion rate,relative abundance-deficiency value of soil nutrient,optimum fertilization amount in most cases.②Due to the influence of the economic production,biological production,different water conditions in paddy field and dry farmland,length of growing season,cropping system(one year before and after the rotation)and so on,sometimes the laws of four aspects above mentioned for the three crops had opposite and gradient variations.
基金Major Scientific and Technological Projects in Guangxi(GUIKE AA17204077)Special Project of Guangxi Science and Technology Base and Talent(GUIKE AD18126012)+2 种基金First-class Discipline(Geography)Construction Project in GuangxiSpecial Funds for"Guangxi Bagui Scholars"Collaborative Innovation Task of Science and Technology Innovation Project of Chinese Academy of Agricultural Sciences—Integration and Demonstration of Green and Efficient Agricultural Technology Innovation in Danjiangkou Water Conservation Area(CAAS-XTCX2016015).
文摘This paper studied the index system of ecological balanced fertilization for three crops by data mining method based on data of"3414 fertilizer field trials"of rice,wheat and maize by published papers from national soil testing and recommendation since 2005.A systematic analysis of the materials and methods,the main research contents,the main research results and the main research conclusions of the column was made,in order to enable readers to understand and grasp the overall contents of the following 15 papers.
基金Collaborative Innovation Task of Science and Technology Innovation Project of Chinese Academy of Agricultural Sciences—Integration and Demonstration of Green and Efficient Agricultural Technology Innovation in Danjiangkou Water Conservation Area(CAAS-XTCX2016015)Major Scientific and Technological Projects in Guangxi(GUIKE AA17204077)+2 种基金Special Project of Guangxi Science and Technology Base and Talent(GUIKE AD18126012)First-class Discipline(Geography)Construction Project in GuangxiSpecial Funds for"Guangxi Bagui Scholars".
文摘This paper studied the index system of ecological balanced fertilization for wheat by data mining method based on data of"3414 fertilizer field trials"of wheat by published papers from national soil testing and recommendation since 2005.The results and conclusions were as follows.①Soil nutrient content could not be used as indicator of fertilizer application of wheat.②The conceptual model of N utilization ratio of wheat for plot was Y N≈a+b×optimum production-c×optimum fertilizer amount of N-d×temperature in growing season-e×rainfall in growing season,and the conceptual model of P conversion rate was Y P≈a+b×optimum production+c×temperature in growing season+d×precipitation in growing season-e×optimum fertilizer amount of P-f×optimum fertilizer amount of K,and the conceptual model of K conversion rate of wheat plots was that,Y K≈a-b×optimum fertilizer amount of K.③The conceptual model of the optimum fertilizer amount of N of wheat for plot was Y N≈a+b×optimum production+c×optimum fertilizer amount of P-d×temperature in growing season-e×rainfall in growing season,and the conceptual model of the optimum fertilizer amount of P was Y P≈a+b×optimum production+c×optimum fertilizer amount of N+d×optimum fertilizer amount of K,and the conceptual model of the optimum fertilizer amount of K was Y K≈a+b×optimum fertilizer amount of P.④The conceptual model of relative abundance-deficiency value of soil N of wheat for plot was that Y N≈a-b×temperature in growing season-c×precipitation in growing season,and the conceptual model of relative abundance-deficiency value of soil P was Y P≈a+b×optimum yield+c×optimum fertilizer amount of N+d×precipitation in growing season-e×optimum fertilizer amount of K,and the conceptual model of relative abundance-deficiency value of soil K was Y K≈a+b×optimum yield+c×optimum fertilizer amount of K.
基金Collaborative Innovation Task of Science and Technology Innovation Project of Chinese Academy of Agricultural Sciences—Integration and Demonstration of Green and Efficient Agricultural Technology Innovation in Danjiangkou Water Conservation Area(CAAS-XTCX2016015)Major Scientific and Technological Projects in Guangxi(GUIKE AA17204077)+2 种基金Special Project of Guangxi Science and Technology Base and Talent(GUIKE AD18126012)First-class Discipline(Geography)Construction Project in GuangxiSpecial Funds for"Guangxi Bagui Scholars".
文摘This paper studied the index system of ecological balanced fertilization for wheat by data mining method based on data of"3414 fertilizer field trials"of wheat by published papers from national soil testing and recommendation since 2005.The results and conclusions were as follows:①the optimum N,P and K fertilization amounts of wheat were within the normal range,and the application of this standard could not cause obvious non-point source pollution.②The conversion rates of N,P and K of wheat were 58.78%,58.63%and 199.88%higher than the utilization ratios of N,P and K under the optimum fertilization amount,respectively.③At present,the soil N for wheat was in a low equilibrium stage,and soil P and K were in the middle and high levels,in which P was in the accumulation stage,and K was in the depletion stage.④The relationship between fertilizer effect or fertility and optimum production had consistency.The fertilizer effect was negatively correlated with the optimum fertilization amounts of its own nutrient and other nutrients.N,P and K fertilizers had mutual promoting effects when they were balanced.Soil nutrient played an inhibitory role in the fertilizer efficiency of its own nutrient.⑤The phosphorus and potassium utilization ratios were significantly positively correlated with the optimum phosphorus fertilization amount and the optimal potassium fertilization amount,which was the scientific basis for phosphorus and potassium concentrated fertilization of wheat.
基金Major Scientific and Technological Projects in Guangxi(GUIKE AA17204077)Special Project of Guangxi Science and Technology Base and Talent(GUIKE AD18126012)+2 种基金First-class Discipline(Geography)Construction Project in GuangxiSpecial Funds for"Guangxi Bagui Scholars"Collaborative Innovation Task of Science and Technology Innovation Project of Chinese Academy of Agricultural Sciences—Integration and Demonstration of Green and Efficient Agricultural Technology Innovation in Danjiangkou Water Conservation Area(CAAS-XTCX2016015).
文摘This paper studied the nitrogen index system of ecological balanced fertilization for rice by data mining method based on data of"3414 fertilizer field trials"of rice by published papers from national soil testing and recommendation since 2005.The results and conclusions were as follows.①Soil nutrient content could not be used as fertilization indicator of rice.②The conceptual model of nitrogen conversion rate of rice for plot was Y N≈a+b×optimum production-c×optimum nitrogen fertilization amount-d×optimum phosphorus fertilization amount,and the conceptual model of phosphorus conversion rate was Y P≈a-b×optimum phosphorus fertilization amount-c×optimum potassium fertilization amount,and the conceptual model of potassium conversion rate was Y K≈a+b×optimum production+c×optimum nitrogen fertilization amount-d×optimum potassium fertilization amount-e×annual average precipitation.③The conceptual model of the optimum nitrogen fertilization amount of rice for plot was Y N≈a+b×optimum production+c×optimum phosphorus fertilization amount-d×annual average precipitation,and the conceptual model of the optimum phosphorus fertilization amount was Y P≈a+b×optimum nitrogen fertilization amount+c×optimum potassium fertilization amount,and the conceptual model of the optimum potassium fertilization amount was Y K≈a+b×optimum phosphorus fertilization amount+c×annual average precipitation.④The conceptual model of relative abundance-deficiency value of soil nitrogen of rice for plot was Y N≈a-b×optimum nitrogen fertilization amount-c×optimum potassium fertilization amount,and the conceptual model of relative abundance-deficiency value of soil phosphorus was Y P≈a+b×soil available potassium-c×optimum potassium fertilization amount,and the conceptual model of relative abundance-deficiency value of soil potassium of rice was Y K≈a-b×optimum potassium fertilization amount.
基金Major Scientific and Technological Projects in Guangxi(GUIKE AA17204077)Special Project of Guangxi Science and Technology Base and Talent(GUIKE AD18126012)+2 种基金First-class Discipline(Geography)Construction Project in GuangxiSpecial Funds for"Guangxi Bagui Scholars"Collaborative Innovation Task of Science and Technology Innovation Project of Chinese Academy of Agricultural Sciences—Integration and Demonstration of Green and Efficient Agricultural Technology Innovation in Danjiangkou Water Conservation Area(CAAS-XTCX2016015).
文摘This paper studied the index system of ecological balanced fertilization for maize by data mining method based on data of"3414 fertilizer field trials"of maize by published papers from national soil testing and recommendation since 2005.The results and conclusions were as follows.①Soil nutrient content could not be used as indicator of fertilizer application of maize.②The conceptual model of N conversion rate of maize for plot was Y N≈a+b×optimum production-c×optimum fertilizer amount of N-d×optimum phosphorus application amount-e×optimum potassium application amount-f×temperature in growth season-g×rainfall in growth season.The conceptual model of P conversion rate of maize for plot was Y P≈a+b×optimum phosphorus application amount-c×optimum nitrogen application amount-d×optimum potassium application amount.The conceptual model of K conversion rate of maize for plot was Y K≈a+b×optimum yield-c×optimum nitrogen application amount-d×optimum phosphorus application amount-e×optimum potassium application amount-f×temperature in growth season-g×rainfall in growth season.③The conceptual model of the optimum fertilizer amount of N of maize for plot was Y N≈a+b×optimum phosphorus application amount+c×optimum potassium application amount+d×temperature in growing season+e×rainfall in growing season,and the conceptual model of the optimum fertilizer amount of P was Y P≈a+b×optimum nitrogen application amount,and the conceptual model of the optimum fertilizer amount of K was Y K≈a+b×optimum nitrogen application amount+c×temperature in growth season+d×rainfall in growth season-e×optimum yield.④The conceptual model of relative abundance-deficiency value of soil N of maize for plot was that Y N≈a,and the conceptual model of relative abundance-deficiency value of soil P was Y P≈a,and the conceptual model of relative abundance-deficiency value of soil K was Y K≈a+b×optimum nitrogen application amount+c×optimum phosphorus application amount.
基金Major Scientific and Technological Projects in Guangxi(GUIKE AA17204077)Special Project of Guangxi Science and Technology Base and Talent(GUIKE AD18126012)+2 种基金First-class Discipline(Geography)Construction Project in GuangxiSpecial Funds for"Guangxi Bagui Scholars"Collaborative Innovation Task of Science and Technology Innovation Project of Chinese Academy of Agricultural Sciences—Integration and Demonstration of Green and Efficient Agricultural Technology Innovation in Danjiangkou Water Conservation Area(CAAS-XTCX2016015).
文摘In this paper,the index system of ecological balanced fertilization for wheat was discussed by data mining method based on this column.Three aspects of provincial average,typical province and all samples were studied,the results and conclusions were as follows:①climate condition was one of the main factors of soil formation,which was also an important basis for the division of wheat producing areas.The proportion of available nutrients was different in different wheat producing areas.This was the result of long-term climate and man-made action,and it constituted the basic fertility pattern of soil available nutrient for wheat in China.②One of the basic fertility indexes of soil for wheat in China was the proportion of available nutrients,which was the theoretical basis for adjusting the proportion of N,P and K fertilizers.③Although the total amount and proportion of available nutrients in different wheat producing areas were different,they can be adjusted to the optimum absorption ratio of wheat by fertilizing measures,so as to achieve the goal of ecological balanced fertilization such as high production and good quality.④The basic soil nutrient indexes of more than 5000 kg/hm 2 of wheat production were less than 6 of hydrolysable N/available P and less than 7 of available K/available P,and the fertilization index was that optimum K fertilization amount was 0.6-1.2 times of optimum P fertilization amount.
基金Major Scientific and Technological Projects in Guangxi(GUIKE AA17204077)Special Project of Guangxi Science and Technology Base and Talent(GUIKE AD18126012)+2 种基金First-class Discipline(Geography)Construction Project in GuangxiSpecial Funds for"Guangxi Bagui Scholars"Collaborative Innovation Task of Science and Technology Innovation Project of Chinese Academy of Agricultural Sciences—Integration and Demonstration of Green and Efficient Agricultural Technology Innovation in Danjiangkou Water Conservation Area(CAAS-XTCX2016015).
文摘This paper studied the index system of ecological balanced fertilization for maize by data mining method based on data of"3414 fertilizer field trials"of maize by published papers from national soil testing and recommendation since 2005.The results and conclusions were as follows:①the optimum N,P and K fertilization amounts of maize were within the normal range,and the application of this standard could not cause obvious non-point source pollution.②The conversion rates of N,P and K of maize were respectively higher than their respective utilization ratios under the optimum fertilization amount.③At present,the soil N for maize was in an absence state,and soil P and K were in a state of not obvious lack.④Optimum N,P and K fertilization amounts were significantly negatively correlated with their respective conversion ratios,respectively,and it provided a quantitative scientific basis for calculating the optimum fertilization amount according to the nutrient conversion rate.Each province can use this significant relationship to guide the determination of the average optimal fertilization amounts of N,P and K and the optimal production in the province.⑤The research results of nutrient conversion rate showed that any excessive application of N,P and K would reduce their own nutrient conversion rates,and may also reduce the conversion rates of other nutrients.The characteristics of crops absorbing N,P and K proportionally required that soil nutrients must be balanced in order to obtain high production,and fertilization was only the main means to regulate soil nutrient balance.
基金Major Scientific and Technological Projects in Guangxi(GUIKE AA17204077)Special Project of Guangxi Science and Technology Base and Talent(GUIKE AD18126012)+2 种基金First-class Discipline(Geography)Construction Project in GuangxiSpecial Funds for"Guangxi Bagui Scholars"Collaborative Innovation Task of Science and Technology Innovation Project of Chinese Academy of Agricultural Sciences—Integration and Demonstration of Green and Efficient Agricultural Technology Innovation in Danjiangkou Water Conservation Area(CAAS-XTCX2016015).
文摘This paper studied the index system of ecological balanced fertilization for rice by data mining method based on data of"3414 fertilizer field trials"of rice by published papers from national soil testing and recommendation since 2005.The results and conclusions were as follows:①the optimum N,P and K fertilization amounts of rice were within the normal range,and the application of this standard could not cause obvious non-point source pollution.②N,P and K conversion ratios were 76.4%,166.58%and 261.89%higher than N,P and K utilization ratios under the optimum fertilizer amount of rice,respectively.③At present,the soil N for rice was in a low equilibrium stage,and soil P and K were in the middle and high level,in which P was in the accumulation stage,while K was in the depletion stage.④The relationship between fertilizer effect or fertility and optimum production had consistency.The fertilizer effect was negatively correlated with the optimum fertilization amount of its own nutrient.N,P and K fertilizers had mutual promoting effect when they were balanced.Soil nutrient played an inhibitory role in the fertilizer efficiency of its own nutrient.Soil nutrient sometimes played a role in promoting the efficiency of other nutrients,and sometimes inhibited them.It was a positive correlation between soil nutrients with the same attribute.
