Carbon Dioxide, Methane, and Nitrous Oxide Emissions from a Rice-Wheat Rotation as Affected by Crop Residue Incorporation and Temperature

Field measurements were made from June 2001 to May 2002 to evaluate the effect of crop residue application and temperature on CO2, CH4, and N2O emissions within an entire rice-wheat rotation season. Rapeseed cake and wheat straw were incorporated into the soil at a rate of 2.25 t hm(-2) when the rice crop was transplanted in June 2001. Compared with the control, the incorporation of rapeseed cake enhanced the emissions of CO2, CH4, and N2O in the rice-growing season by 12.3%, 252.3%, and 17.5%, respectively, while no further effect was held on the emissions of CO2 and N2O in the following wheat-growing season. The incorporation of wheat straw enhanced the emissions of CO2 and CH4 by 7.1% and 249.6%, respectively, but reduced the N2O emission by 18.8% in the rice-growing season. Significant reductions of 17.8% for the CO2 and of 12.9% for the N2O emission were observed in the following wheat-growing season. A positive correlation existed between the emissions of N2O and CO2 (R-2 = 0.445, n = 73,p < 0.001) from the rice-growing season when N2O was emitted. A trade-off relationship between the emissions of CH4 and N2O was found in the rice-growing season. The CH4 emission was significantly correlated with the CO2 emission for the period from rice transplantation to field drainage, but not for the entire rice-growing season. In addition, air temperature was found to regulate the CO2 emissions from the non-waterlogged period over the entire rice-wheat rotation season and the N2O emissions from the nonwaterlogged period of the rice-growing season, which can be quantitatively described by an exponential function. The temperature coefficient (Q(10)) was then evaluated to be 2.3+/-0.2 for the CO2 emission and 3.9+/-0.4 for the N2O emission, respectively.

A Field Study on Effects of Nitrogen Fertilization Modes on Nutrient Uptake,Crop Yield and Soil Biological Properties in Rice-Wheat Rotation System

Rational application of nitrogen （N） fertilizers is an important measure to raise N fertilizer recovery rate and reduce N loss.A two-year field experiment of rice-wheat rotation was employed to study the effects of N fertilization modes including a N fertilizer reduction and an organic manure replacement on crop yield,nutrient uptake,soil enzyme activity,and number of microbes as well as diversity of microbes.The result showed that 20% reduction of traditional N fertilizer dose of local farmers did not significantly change crop yield,N uptake,soil enzyme activity,and the number of microbes （bacteria,actinomycetes,and fungi）.On the basis of 20% reduction of N fertilizer,50% replacement of N fertilizer by organic manure increased the activity of sucrose,protease,urease,and phosphatase by 46-62,27-89,33-46,and 35-74%,respectively,and the number of microbes,i.e.,bacteria,actinomycetes,and fungi by 36-150,11-153,and 43-56%,respectively.Further,organic fertilizer replacement had a Shannon＇s diversity index （H） of 2.18,which was higher than that of other modes of single N fertilizer application.The results suggested that reducing N fertilizer by 20% and applying organic manure in the experimental areas could effectively lower the production costs and significantly improve soil fertility and biological properties.

Yield Gap Analysis of Wheat in Rice-wheat Rotation Regions of Anhui Province,China

The present study was planned to analyze the yield gap of wheat and its production constraints in order to explore the approaches for narrowing the yield gap of wheat in different wheat-rice rotation regions of Anhui Province. The production status and limiting factors of wheat in three rice-wheat rotation regions which are named Region Ⅰ,Region Ⅱ and Region Ⅲ were surveyed by using participatory rural appraisal method. The personnel,who were engaged in wheat production in rice-wheat rotation regions of Anhui Province,mainly ageing from 41 to 60,accounted for 79% of the total personnel in the regions. There were significant differences in yield of wheat which was planted after rice in Anhui. The yield was ranging from 8 907. 00 to 2 700. 00 kg/ha from north to south with an average of 4 978. 5 kg/ha,and the rank of overall average yields at province level was Region Ⅰ( 5 685. 60 kg/ha) > Region Ⅱ( 5 600. 10 kg/ha) > Region Ⅲ( 3 048. 60 kg/ha). The average yield gap of wheat in wheat-rice rotation regions at province level was up to 2 637. 00 kg/ha,and the extreme yield gaps per hectare in the same region were 2 778. 00 kg( Region Ⅰ),2 502. 00 kg( Region Ⅱ) and 1 575. 00 kg( Region Ⅲ) respectively. The objective constraints were Fusarium head blight and pre-harvest sprouting;the subjective constraints were variety selection and layout,poor sowing quality and low seedling quality;social constraints were high cost,low market price and poor efficiency;and ecological constraints were poor soil texture,soil infertility and poor water-and-fertilizer retention. The yield gap of wheat in rice-wheat rotation regions can be effectively reduced by improving yield potential of low-and-medium-yielding fields. Selecting appropriate wheat varieties and layout,constructing disease forecast system,improving agricultural machinery and social service organizations of plant protection,and strengthening scientific training as well as technological training of new agricultural operators and agricultural machinery technicians are the core means to narrowing the yield gap of wheat in rice-wheat rotation regions at province scale.

Responses of Wheat Production, Quality, and Soil Profile Properties to Biochar Applied at Different Seasons in a Rice-Wheat Rotation

In the rice-wheat rotation system,biochar(BC)can be applied at the initiation of the rice or wheat season.Here,we compared the effects of BC that were applied at two different crop seasons on wheat production,quality,and soil profile properties in a rice-wheat rotation system with nitrogen(N)fertilizer applied at 280 kg/ha rate.Results showed that both wheat grain production and N recovery use efficiency were influenced by BC applied at two crop seasons.Biochar application did not affect the total non-essential amino-acid,but when applied during wheat season,BC significantly(p<0.05)increased total essential amino acid in grain by 12.3%,particularly for the valine(+48.2%),methionine(+43.8%),and isoleucine(+10.3%).We found that BC significantly(p<0.05)decreased the pH of soil at 0–6 cm and 20–30 cm by 0.14–0.18 and 0.05–0.08 units,respectively.The NH4+-N content of the whole observed soil profile were reduced by BC application,however,the effect of BC on NO3–-N content varied with the application season and profile depth.Interestingly,BC applied at wheat and rice season significantly(p<0.05)improved topsoil N contents by 48.4%and 19.7%,respectively.In addition,data suggested that BC applied during wheat season performed better in enhancing soil available phosphorus,potassium,and organic matter contents.In conclusion,we suggest that the optimum application time of BC for enhancing crop production and quality(take amino-acid content for example)and improving soil fertility is at the initiation of the wheat season.

Characteristics of Nitrogen and Phosphorus Losses in Different Crop Rotation Systems in the North of Erhai Lake Basin

[Objective] Nitrogen and phosphorus losses of surface runoff in various crop rotation systems in the north of Erhai Lake basin were studied with the objective to provide references for risk evaluation of environmental pollution and formulating countermeasures to control the nonpoint source pollution from agriculture.[Method] Water samples collected in four typical crop rotation systems distributed in seven towns（townships） in the north of Erhai Lake basin were investigated,as well as the fertilizer input,to explore the dynamic change of nitrogen and phosphorus content in surface water of farmland and ditch water,and the correlation between fertilizer input and the concentrations of nitrogen and phosphorus in the surface water of farmland and in the ditch water.[Result] The results showed that nitrogen loss in surface water of farmland in different crop rotation systems differed greatly,and the risk of nitrogen loss was 38% lower in broad bean-rice crop rotation than that in garlic-rice crop rotation.The water soluble nitrogen was the primary form of nitrogen loss.The content of water soluble nitrogen was significantly higher in garlic-rice crop rotation than that in the other rotation systems,and the concentrations of nitrogen in the surface water of farmland in different crop rotation systems followed the sequence below：garlic-rice crop rotationryegrass-rice crop rotationbroad bean-rice crop rotationrape-rice crop rotation.The loss of phosphorus in the surface water of farmland was relatively low and phosphorus combined with silt was the primary form for phosphorus loss.There was no significant difference of the loss of various forms of phosphorus in different crop rotation systems.The contents of total nitrogen and total phosphorus in the surface water of farmland were higher than that in ditch water,with increasing rates of total nitrogen and total phosphorus in ditch water of 72% and 82%,respectively.Topdressing was the critical reason for the high concentrations of nitrogen and phosphorus in the surface water,which also caused the increasing load to the ditch water.[Conclusion] Both the nitrogen and phosphorus loss were the highest in garlic-rice crop rotation.Reasonable crop rotation systems should be established based on both the environmental and economic benefits.This study provided references for controlling the nonpoint source pollution of farmland and improving the water quality of Erhai Lake.

Seasonal and Interannual Variations of Carbon Exchange over a Rice–Wheat Rotation System on the North China Plain

Rice-wheat （R-W） rotation systems are ubiquitous in South and East Asia, and play an important role in modulating the carbon cycle and climate. Long-term, continuous flux measurements help in better understanding the seasonal and interannual variation of the carbon budget over R-W rotation systems. In this study, measurements of CO2 fluxes and meteorological variables over an R-W rotation system on the North China Plain from 2007 to 2010 were analyzed. To analyze the abiotic factors regulating Net Ecosystem Exchange （NEE）, NEE was partitioned into gross primary production （GPP） and ecosystem respiration. Nighttime NEE or ecosystem respiration was controlled primarily by soil temperature, while daytime NEE was mainly determined by photosythetically active radiation （PAR）. The responses of nighttime NEE to soil temperature and daytime NEE to light were closely associated with crop development and photosynthetic activity, respectively. Moreover, the interannual variation in GPP and NEE mainly depended on precipitation and PAR. Overall, NEE was negative on the annual scale and the rotation system behaved as a carbon sink of 982 g C m 2 per year over the three years. The winter wheat field took up more CO2 than the rice paddy during the longer growing season, while the daily NEE for wheat and rice were -2.35 and -3.96 g C m-2, respectively. After the grain harvest was subtracted from the NEE, the winter wheat field became a moderately strong carbon sink of 251-334 g C m-2 per season, whereas the rice paddy switched to a weak carbon sink of 107-132 per season.

A Process-based Model of N_2O Emission from a Rice-Winter Wheat Rotation Agro-Ecosystem:Structure,Validation and Sensitivity

In order to numerically simulate daily nitrous oxide （N2O） emission from a rice-winter wheat rotation cropping system, a process-based site model was developed （referred to as IAP-N-GAS） to track the movement and transformation of several forms of nitrogen in the agro-eeosystem, which is affected by climate, soil, crop growth and management practices. The simulation of daily N2O fluxes, along with key daily environmental variables, was validated with three-year observations conducted in East China. The validation demonstrated that the model simulated well daily solar radiation, soil temperature and moisture, and also captured the dynamics and magnitude of accumulated rice aboveground biomass and mineral nitrogen in the soil. The simulated daily N2O emissions over all three years investigated were generally in good agreement with field observations. Particularly well simulated were the peak N2O emissions induced by fertilizations, rainfall events or mid-season drainages. The model simulation also represented closely the inter-annuM variation in N2O emission. These validations imply that the model has the capability to capture the general characteristics of N2O emission from a typical rice-wheat rotation agro-ecosystem. Sensitivity analyses revealed that the simulated N2O emission is most sensitive to the fertilizer application rate and the soil organic matter content, but it is much less sensitive to variations in soil pH and texture, temperature, precipitation and crop residue incorporation rate under local conditions.

Realizing high efficiency and large-area sterilization by a rotating plasma jet device

By tilting a plasma jet and rotating 360°,a large-area can be scanned and sterilized in a short time.Compared with the previous array device,this pipe has the significant advantages of high sterilization uniformity and low gas consumption.Firstly,a rotatable plasma jet device,which can control the swing and rotation of a jet pipe,is designed,and a corresponding theoretical model is established to guide the experiment.Secondly,with Staphylococcus aureus(S.aureus)and Escherichia coli(E.coli)as the target bacteria,the device achieves a short sterilization time of 158 s—the minimum sterilization flow of S.aureus and E.coli is 0.8 slm and 0.6 slm,respectively.The device is compared with an array plasma sterilization device in terms of sterilization speed and gas consumption.The results show that the device is not only better than an array plasma sterilization device with respect to scanning uniformity,but also far less than the array plasma sterilization device in gas consumption of 5 slm.Therefore,the device has great potential in applications involving efficient,large-area sterilization.

Measurements of the effective mass transfer areas for the gas–liquid rotating packed bed

Rotating packed bed(RPB) is one of the most effective gas–liquid mass transfer enhancement reactors, its effective specific mass transfer area(ae) is critical to understand the mass transfer process. By using the NaOH–CO_(2) chemical absorption method, the aevalues of three RPB reactors with different rotor sizes were measured under different operation conditions. The results showed that the high gravity factor and liquid flow rate were major affecting factors, while the gas flow rate exhibited minor influence.The radius of packing is the dominant equipment factor to affect aevalue. The results indicated that the contact area depends on the dispersion of the liquid phase, thus the centrifugal force of rotating packed bed greatly influenced the aevalue. Moreover, the measured ae/ap(effective specific mass transfer area/specific surface area of packing) values were fitted with dimensionless correlation formulas. The unified correlation formula with dimensionless bed size parameter can well predict the experimental data and the prediction errors were within 15%.

Assessment of CH_(4) flux and its influencing drivers in the rice-wheat agroecosystem of the Huai River Basin,China

To understand the CH_(4) flux variations and their climatic drivers in the rice-wheat agroecosystem in the Huai River Basin of China,the CH_(4) flux was observed by using open-path eddy covariance at a typical rice-wheat rotation system in Anhui Province,China from November 2019 to October 2021.The variations and their drivers were then analyzed with the Akaike information criterion method.CH_(4) flux showed distinct diurnal variations with single peaks during 9:00-13:00 local time.The highest peak was 2.15μg m^(-2)s^(-1)which occurred at 11:00 in the vegetative growth stage in the rice growing season(RGS).CH_(4) flux also showed significant seasonal variations.The average CH_(4)flux in the vegetative growth stage in the RGS(193.8±74.2 mg m^(-2)d^(-1))was the highest among all growth stages.The annual total CH_(4) flux in the non-rice growing season(3.2 g m^(-2))was relatively small compared to that in the RGS(23.9 g m^(-2)).CH_(4) flux increased significantly with increase in air temperature,soil temperature,and soil water content in both the RGS and the non-RGS,while it decreased significantly with increase in vapor pressure deficit in the RGS.This study provided a comprehensive understanding of the CH_(4) flux and its drivers in the rice-wheat rotation agroecosystem in the Huai River Basin of China.In addition,our findings will be helpful for the validation and adjustment of the CH_(4) models in this region.

Experiences and Research Perspectives on Sustainable Development of Rice-Wheat Cropping Systems in the Chengdu Plain, China

The rice and wheat cropping pattern is one of the main cropping systems in the world. A large number of research results showed that successive cropping of rice and wheat resulted in a series of problems such as hindering nutrition absorption, gradual degeneration of soil fertility, decline of soil organic matter, and increased incidence of diseases and pests. In China, especially in the Chengdu plain where rice-wheat cropping system is practiced, productivity and soil fertility was enhanced and sustained. This paper reviews the relevant data and experiences on rice-wheat cropping in the Chengdu Plain from 1977 to 2006. The principal sustainable strategies used for rice-wheat cropping systems in Chengdu Plain included： 1） creating a favorable environment and viable rotations; 2） balanced fertilization for maintenance of sustainable soil productivity; 3） improvement of crop management for higher efficiency; and 4） use the newest cultivars and cultivation techniques to upgrade the production level. Future research is also discussed in the paper as： 1） the constant topic： a highly productive and efficient rice-wheat cropping system for sustainable growth; 2） the future trend： simplified cultivation techniques for the rice-wheat cropping system; 3） the foundation： basic research for continuous innovation needed for intensive cropping. It is concluded that in the rice-wheat cropping system, a scientific and reasonable tillage/cultivation method can not only avoid the degradation of soil productivity, but also maintain sustainable growth in the long run.

Prediction of mass transfer coefficients in an asymmetric rotating disk contactor using effective diffusivity

Mass transfer characteristics have been investigated in a 113 mm diameter asymmetric rotating disk contactor of the pilot plant scale for two different liquid–liquid systems. The effects of operating parameters including rotor speed and continuous and dispersed phase velocities on the volumetric overall mass transfer coefficients are investigated. The results show that the mass transfer performance is strongly dependent on agitation rate and interfacial tension, but only slightly dependent on phase flow rates. In this study, effective diffusivity is used instead of molecular diffusivity in the Grober equation for estimation of dispersed phase overall mass transfer coefficient.The enhancement factor is determined experimentally and there from an empirical expression is derived for prediction of the enhancement factor as a function of Reynolds number. The predicted results compared to the experimental data show that the proposed correlation can efficiently predict the overall mass transfer coefficients in asymmetric rotating disk contactors.

Use of axial dispersion model for determination of Sherwood number and mass transfer coefficients in a perforated rotating disc contactor

The mass transfer process in a perforated rotating disk contactor(PRDC) using a toluene-acetone-water system was investigated.The volumetric overall mass transfer coefficients are calculated in a PRDC column.Both mass transfer directions are considered in experiments.The influences of operating variables containing agitation rate,dispersed and continuous phase flow rates and mass transfer in the extraction column are studied.According to obtained results,mass transfer is significantly dependent on agitation rate,while the dispersed and continuous phase flow rates have a minor effect on mass transfer in the extraction column.Furthermore,a novel empirical correlation is developed for prediction of overall continuous phase Sherwood number based on dispersed phase holdup,Reynolds number and mass transfer direction.There has been great agreement between experimental data and predicted values using a proposed correlation for all operating conditions.

湖北襄阳地区水稻落粒、杆枯等不正常生长现象的解析

襄阳地区是湖北省重要的粮仓地,稻-麦轮作是当地主要的栽培模式。农户多年自留种后水稻生产上出现落粒和穗腐,为了探讨引起水稻不良生长的原因,进行现场取样和调查分析。采用形态特征观察以及分子生物学鉴定,以市场所购‘黄华占’作对照、经41对水稻分子特异性标记检测,以及使用生长速率法测定化学药剂对分离到的病原菌的毒力。结果表明:病样分离获得4种致病菌,分别为稻黑孢菌、层出镰孢菌、木贼镰孢菌和禾谷镰孢菌;显示农户连续6年自留的‘黄华占’种子未发生变异,连续6年自留的稻种播于免耕田中,所获的稻谷有12个指纹不同于对照,表明自留6年的‘黄华占’稻种在田间生长中出现变异;70%唑醚·丙森锌WG和23%醚菌·氟环唑SC对致病菌的生长均有抑制作用。多年连续留种会引起稻种生命力衰减,导致田间水稻长势衰弱,易遭受病害侵袭,出现异常生长现象。正确用种、科学管理及适期药剂防治是保障水稻安全生产的重要举措。

基于视觉图像的飞行区大型目标监视方法改进研究

机场飞行区现使用的场面监视方法存在着定位偏差较大、不稳定、易跳变、皆为点源定位等问题。针对这些问题,设计了基于视觉图像的飞行区监视方法,实现快速准确的目标检测和轮廓定位,使飞行区监视更加稳定精确。提出了一种基于MobileNetV3和YOLOv5的网络模型(以下称为MobileNetV3-YOLOv5),即在YOLOv5的主干中使用MobileNetV3,来提高对目标的检测速度和准确度;提出了一种基于优化特征点提取的改进定向快速旋转简报(Oriented FAST and Rotated BRIEF,ORB)算法,将图像分割成多个区域,分别提取每个区域的特征点,从而提高目标识别框内区域的特征点识别数量,再进行特征点聚类筛选,最后根据识别目标类型采用最小包围盒进行轮廓划分,得到目标的轮廓定位。试验结果表明:MobileNetV3-YOLOv5方法对比原始YOLOv5模型,在识别目标准确率方面提升5百分点,在效率方面提升14张/s;同时在0~60 m的范围内,轮廓估计误差仅为2.9%;体现了所提出的监视方法的有效性,可以提升飞行区监视定位准确性和运行安全性。

Field experimental study on optimal design of the rotary strip-till tools applied in rice-wheat rotation cropping system

The rice-wheat rotation system plays a significant role in Asian agriculture.The introduction of strip-tillage into the rice-wheat system for wheat planting offers a way to use conservation tillage practices to improve the seedbed quality,retain residue between rows and reduce energy input.A field experiment was conducted using an in-situ test rig.Three types of blade(bent C,straight and hoe)were evaluated in four tool configurations at four rotary speeds(180 r/min,280 r/min,380 r/min and 510 r/min)in a paddy soil.Furrow shape parameters,tillage-induced soil structures and energy consumption were assessed.Results showed that the straight blade configuration failed to create a continuous furrow at either 180 r/min or 510 r/min.The bent C blade configuration produced a uniform furrow profile but its furrow backfill was poor and unsuitable for seeding.The hoe blade configuration cut a continuous furrow and better tillage-induced soil structure,but it produced a much wider and non-uniform furrow shape.The mixed blade configuration(central hoe blades with two straight blades aside)provided a uniform furrow with good backfill and fine tilth by utilizing both the cutting effect of straight blades on the furrow boundaries and tensile fracturing of the furrow soil by the hoe blades.The torque of the mixed blade configuration was comparable with the bent C blade but was less than the hoe blades.Hence,a mixed blade configuration was recommended for rotary strip-tillage seeding using in rice-wheat system.

煤油燃料宽域冲压旋转爆震燃烧特性

通过三维数值仿真的方法,研究了Ma=3~7飞行工况下,煤油燃料冲压旋转爆震燃烧特性。在Ma=3飞行工况下,由于燃料雾化蒸发效果较差,无法实现煤油燃料的爆震燃烧。Ma=4, 5, 6的飞行工况下,随着飞行Mach数的增大,波头数目整体上逐渐增多,分别为单波、三波、五波模态;但传播速度逐渐减小;冲压模态下,液态燃料雾化蒸发效果较好,但流场内均不同程度地残存有煤油蒸气,其未参加反应便排出燃烧室。Ma=7的飞行工况下,由于来流接近CJ速度,流场将以驻定爆震模态组织燃烧。

烟区不同类型油菜秸秆腐解及养分释放特性研究

本研究旨在探讨山东和四川烟区适合与烟草轮作的油菜品种,并分析其秸秆腐解及养分释放特性。通过采用尼龙网袋法,在室内模拟田间条件下对2种类型(白菜型和甘蓝型)的4个冬油菜品种进行培养,观察秸秆的腐解过程和养分释放情况。结果显示,培养前10 d,油菜秸秆快速腐解,各养分也快速释放,养分最终释放率表现为K>N>P>C;腐解进程中,秸秆碳氮比有所波动,但大致呈上升趋势;白菜型油菜秸秆的腐解程度、碳和氮的释放率高于甘蓝型油菜,而钾的释放率低于甘蓝型油菜,磷的释放率表现出地区差异;四川烟区油菜秸秆的腐解程度及碳、氮、磷素的释放率高于山东烟区,钾的释放率高于山东白菜型油菜;油菜秸秆腐解可显著提高供试土壤中有机质、氮、磷和钾素的含量,但不同烟区、不同类型油菜秸秆的增效程度有所差异。从秸秆还田利用的角度来看,2烟区中的白菜型油菜品种更适合与烟草轮作种植。

华东稻麦轮作区立旋自走电驱动式定角度清秸机设计与试验

传统卧旋式清秸装置动土量较大,且湿黏土壤抛起时易黏附在机器上,导致作业质量下降、油耗增加,影响装置作业稳定性,针对这一问题,设计一种立旋式定角度清秸机,通过结构设计与分析实现清秸刀齿恒定角度作业,避免秸秆二次带回种床,通过对清秸刀齿切土迹距分析确定装置关键结构参数,应用三因素三水平正交试验方法,以作业速度、迹距系数和入土深度为试验因素,清秸率和单位面积作业功耗为试验评价指标,对影响清秸机作业性能的相关参数进行试验与优化。试验结果表明,当参数组合为作业速度4~8 km/h、迹距系数2和入土深度10 mm时,清秸率不小于89.7%、单位面积作业功耗不大于1.84 W·h/m^(2),整个作业过程均未发生土壤黏附现象。研究结果可突破湿黏土壤环境下播种装备作业局限,为稻麦轮作全程机械化提供技术支撑。

基于面积差异等效建模的电液比例位置系统FMAPID控制

公路边坡护坡骨架施工车是聚焦于公路边坡土壤开槽和水泥混凝土滑模的工程机械装备。针对公路边坡护坡骨架施工车旋转臂在边坡环境的运动控制问题,设计一种基于模糊多参数自适应比例积分微分(proportional integral derivative,PID)的位置反馈控制策略。考虑到非对称液压缸两腔的差异,采用面积差异等效建模法建立阀控非对称液压缸的线性数学模型。通过定义模糊子集、选取隶属函数、建立模糊规则,使用模糊多参数自适应PID控制算法,实现旋转臂非对称液压缸位置控制。仿真和试验结果表明,基于面积差异等效数学模型的模糊多参数自适应PID能够有效地提高液压缸位置跟踪控制精度,验证了所提控制算法的有效性。