Structure and Change of Costs for Flue-cured Tobacco Production:A Case Study of Liuyang Tobacco Growing Areas

On the basis of consulting related information and data,costs for flue-cured tobacco production were surveyed and analyzed with Liuyang tobacco growing areas as an example.Results showed that there is rise and fall in fertilizer cost for flue-cured tobacco production;change in pesticide and agricultural plastic film is little;other costs for flue-cured tobacco production rise rapidly in recent years.Besides,there is certain reduction in labor units per mu for flue-cured tobacco production;labor price has an annual growth rate of 15%-25%.The proportion of labor cost to total cost for flue-cured tobacco production is increasing,thus rise of labor cost is the major factor promoting rise of costs for flue-cured tobacco production.Through adjustment of purchasing price and various subsidies,the change of per mu yield is a decisive factor influencing benefits of flue-cured tobacco production.

Age Structure and Change Trend of Tobacco Farmers:A Case Study of Shashi Town,Liuyang City,Hunan Province

Taking the tobacco-growing area of Shashi Town,Liuyang City as the object,the number of registered,newly added and resigned tobacco farmers in each year,average age,number and proportion of tobacco farmers of different ages,number and proportion of tobacco farmers born in different eras,as well as planting scale and planting history of flue-cured tobacco in the last 10 years were analyzed statistically.The results showed that the number of tobacco farmers in Shashi Town showed a rapid decline trend from 2012 to 2018,while the average age continuously increased,and the average planting scale rose in a wave like way.From 2019 to 2021,the decline rate of the number of tobacco farmers slowed down,and the average planting scale continuously increased,while the aging of tobacco farmers accelerated.Meantime,the birth years of tobacco farmers were further concentrated in the 1960s,and they were mainly at the age of 50-59.The tobacco industry in Shashi Town of Liuyang City is facing the crisis of aging tobacco farmers and no successor of flue-cured tobacco planting,and it is predicted that the next 5-10 years will continue the change trend from 2019 to 2021.

Security-aware Signal Packing Algorithm for CAN-based Automotive Cyber-physical Systems

Network and software integration pose severe challenges in cyber-security for controller area network (CAN)-based automotive cyber-physical system (ACPS), therefore we employ message authentication code (MAC) to defend CAN against masquerade attack, but the consequent bandwidth overhead makes it a necessity to find the tradeoff among security, real-time and bandwidth utilization for signal packing problem (SPP) of CAN. A mixed-security signal model is firstly proposed to formally describe the properties and requirements on security and real-time for signals, and then a mixed-integer linear programming (MILP) formulation of SPP security-aware signal packing (SASP) is implemented to solve the tradeoff problem, where the bandwidth utilization is improved and the requirements in both security and real-time are met. Experiments based on both society of automotive engineers (SAE) standard signal set and simulated signal set showed the effectiveness of SASP by comparing with the state-of-the-art algorithm. © 2014 Chinese Association of Automation.

Analysis of Growth Laws of Leaves of Flue-cured Tobacco in Various Periods

The growth laws of leaves of flue-cured tobacco in different positions in various periods were summarized. The results showed that the growth speed of new leaves of flue-cured tobacco increased constantly until their growth was the fastest, and then it reduced irreversibly. The length and width of leaves in each position increased fastest when they grew depending on photosynthates instead of or- ganic compounds from functional leaves. Therefore, it is concluded that the increases of leaf length, width and area, and dry matter, and the peak of photosynthetic rate appear successively during the process of leaves of flue-cured tobacco, and the leaf area correction coefficient of leaves of flue-cured tobacco is related to the shape of leaves, which are affected by leaf position and the variety of flue-cured tobacco. The study can provide scientific reference for further research on the growth laws of leaves of flue-cured tobacco.

Analysis of Employment Trend in Flue-Cured Tobacco Planting

Based on the investigation of the amount of labor used in each production link of flue-cured tobacco planting in Liuyang since 1989,and through the analysis of the changes of labor-related factors,it is concluded that the amount of labor used in tobacco planting in Liuyang experienced a significant increase and relatively stable stage in the early 1990s,and it has been declining continuously since the beginning of the 21st century;the change of flue-cured tobacco planting technology mode,as well as mechanized,large-scale and specialized production are the main factors that affect the change of the amount of labor used in flue-cured tobacco planting in Liuyang.Based on the method of changing the technical model to reduce amount of labor used,the types of labor used for planting of flue-cured tobacco can be divided into the following types:reducing the amount of labor by technical methods;reducing the amount of labor by making use of weather;reducing the amount of labor by using drugs;reducing the amount of labor used at the cost of reducing the technical implementation standards of a certain production link.The change of labor used in flue-cured tobacco planting is not only related to the cost and price factors,but also related to the profound social and economic background.In the future,reducing labor and cost is the trend of flue-cured tobacco production,and mechanization,large-scale and specialized production are the main development direction of flue-cured tobacco production,but under the condition that flue-cured tobacco production is still dominated by manual operation,maintaining a certain amount of labor is still the basis for maintaining high quality of flue-cured tobacco planting at present.

Development of Customized Production Machine for Flue-cured Tobacco Formula Nutritional Soil

On the basis of full investigation and repeated trials,nutritional soil composed of cake fertilizer,mushroom residue,cow dung and calcium magnesium phosphate fertilizer was determined as an alternative for traditional flue-cured tobacco fired ash soil.In accordance with the feed grinding,mixing and processing integrated principle,processing machine for flue-cured tobacco nutritional soil was developed.The clogging problem of mixing box was solved by improving grinding and stirring method of mixing system.Mechanized and large-scale production and commercialized supply of flue-cured tobacco nutritional soil was piloted to simplify the production process and reduce the production cost of nutritional soil for flue-cured tobacco and meet the needs of green development of tobacco production,thereby creating good social and economic benefits.