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Knowledge representation and decoupling analysis on failure mechanisms of remotely controlled intelligent machinery
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作者 Liming Gou Jian Zhang Naiwen Li 《Information Processing in Agriculture》 EI 2022年第1期80-89,共10页
Remotely controlled intelligent machinery has complications,including loose manage-ment of failure information,low information availability,and coupling influence among systems,which can be effectively solved by analy... Remotely controlled intelligent machinery has complications,including loose manage-ment of failure information,low information availability,and coupling influence among systems,which can be effectively solved by analyzing the system state and information characteristics of the equipment.Taking intelligent agricultural machinery as the object,this study applies the knowledge representation method to explore equipment failure states’informational features and construct a knowledge framework model of system fail-ure representation relations and a complex network conceptual model to visualize the fail-ure information more intuitively and facilitate systematic management and utilization.The feedback-based decoupling analysis method uncouples the coupling between subsys-tems,identifying the critical state of decoupling well.It attempts to apply the knowledge representation and decoupling analysis to remotely controlled intelligent agricultural machinery equipment.Through the example,the result further illustrates the feasibility of knowledge representation and decoupling for remotely controlled intelligent agricultural machinery systems and provides essential support for better failure analysis. 展开更多
关键词 remotely controlled Failure mechanisms Knowledge representation Decoupling analysis
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Impact of environmental regulations on the efficient control of industrial pollution in China 被引量:1
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作者 Mian Yang Xinghong Yan Qiangyi Li 《Chinese Journal of Population,Resources and Environment》 2021年第3期230-236,共7页
The continuous progress of industrialization is a fundamental cause of China’s increasingly severe environmental pollution problem.Improving the efficiency of industrial pollution control is an inevitable choice to e... The continuous progress of industrialization is a fundamental cause of China’s increasingly severe environmental pollution problem.Improving the efficiency of industrial pollution control is an inevitable choice to effectively decrease pollution emissions,thus winning the battle of pollution prevention and control.In this paper,we used the stochastic frontier analysis(SFA)model to measure the provincial efficiency of industrial pollution control based on the input and output data of industrial pollution control of 29 administrative provinces in China from 2000 to 2017.On this basis,a spatial econometric model was used to explore the influence of environmental regulation intensity on the efficiency of industrial pollution control.In addition,the spatial spillover effect of pollution reduction was thoroughly examined.The results show that:(1)The efficiency of industrial pollution control in China has improved year by year,but the overall efficiency is still low,with the average value increasing from 0.165 in 2000 to 0.309 in 2017.Furthermore,there is significant regional heterogeneity with the highest efficiency level in the east and lowest efficiency level in the west.(2)By increasing the financial and material input,the efficiency of industrial pollution control has increased.However,the increase of human input has not been so helpful.(3)The global Moran’s I index is significantly greater than zero,indicating a strong spatial correlation and agglomeration in the efficiency of industrial pollution control,which is reflected in high-high agglomeration in the eastern region and low-low agglomeration in the western region.(4)Stringent environmental regulation has a positive effect on improving the efficiency of industrial pollution control.It also imposes a positive spatial spillover effect,indicating a strategic interaction and coordination of regional pollution control.In line with this,related proposals have been made to optimize the investment structure for environmental pollution control,establish a flow mechanism for the factor market,and strengthen the environmental responsibility awareness of state-owned enterprises.On this basis,we expect to provide a policy for improving the efficiency of industrial pollution control and promoting regional joint pollution control in China. 展开更多
关键词 Industrial pollution control efficiency environmental regulation Stochastic frontier analysis Spatial spillover effect
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Coordination Control of Greenhouse Environmental Factors 被引量:2
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作者 Feng Chen Yong-Ning Tang Ming-Yu Shen 《International Journal of Automation and computing》 EI 2011年第2期147-153,共7页
Optimal control of greenhouse climate is one of the key techniques in digital agriculture.Greenhouse climate,a nonlinear and uncertain system,consists of several major environmental factors such as temperature,humidit... Optimal control of greenhouse climate is one of the key techniques in digital agriculture.Greenhouse climate,a nonlinear and uncertain system,consists of several major environmental factors such as temperature,humidity,light intensity,and CO 2 concentration.Due to the complex coupled correlations,it is a challenge to achieve coordination control of greenhouse environmental factors.This paper proposes a model-free coordination control approach for greenhouse environmental factors based on Q-learning.Coordination control policy is found through systematic interaction with the dynamic environment to achieve optimal control for greenhouse climate with the control cost constraints.In order to decrease systematic trial-and-error risk and reduce the computational complexity in Q-learning algorithm,case-based reasoning (CBR) is seamlessly incorporated into the Q-learning process.The experimental results demonstrate that this approach is practical,highly effective and efficient. 展开更多
关键词 Q-LEARNING case-based reasoning (CBR) greenhouse environmental factors coordination control coupled correlation trial-and-error.
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Weed Control, Environmental Impact, and Net-Profit of Two-Pass Weed Management Strategies in Dicamba-Resistant Soybean (<i>Glycine max</i>) Using Conventional Tillage
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作者 Matthew G. Underwood Nader Soltan +4 位作者 David C. Hooker Darren E. Robinson Joseph P. Vink Clarence J. Swanton Peter H. Sikkema 《American Journal of Plant Sciences》 2017年第13期3414-3428,共15页
Traditional two-pass weed management strategies need to be compared with new strategies in glyphosate/dicamba-resistant soybean. Weed control, soybean yield, partial profitability and environmental impact (EI) were ev... Traditional two-pass weed management strategies need to be compared with new strategies in glyphosate/dicamba-resistant soybean. Weed control, soybean yield, partial profitability and environmental impact (EI) were evaluated in glyphosate/dicamba-resistant soybean using dicamba applied alone or in a tank-mix with dimethenamid-P applied preemergence (PRE). Trials were conducted at three locations during 2014 and 2015. Several PRE herbicides provided excellent control of broadleaf and grass weeds. Dicamba provided > 91% control of broadleaf weeds, and the addition of dimethenamid-P improved grass control. All weed species at the trial locations were controlled > 94% following a postemergence (POST) application of glyphosate. Weed interference reduced soybean seed yield 33% where no herbicide was applied. A single POST application of glyphosate had the lowest EI. Several treatments improved early-season weed control and reduced early-season weed density and biomass compared to glyphosate and had similar EI values. In this study, there was no benefit to yield or partial profit by including a PRE herbicide for weed management;however, the inclusion of multiple modes-of-action in a herbicide program may reduce the selection for herbicide-resistant weeds. 展开更多
关键词 Density environmental Impact Injury PROFIT analysis TILLAGE Yield Weed control
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Design of Greenhouse Environment Control System Based on Internet of Things 被引量:9
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作者 Shen Wei-zheng Wang Shi-yu +2 位作者 Nagi Eltieb Babker Eltieb Hou Han-dan Zheng Cheng 《Journal of Northeast Agricultural University(English Edition)》 CAS 2018年第2期54-64,共11页
There are some disadvantages, such as complicated wiring, high cost, poor monitoring flexibility, low accuracy and high energy consumption in traditional greenhouse environment monitoring system which based on previou... There are some disadvantages, such as complicated wiring, high cost, poor monitoring flexibility, low accuracy and high energy consumption in traditional greenhouse environment monitoring system which based on previous wireless sensor networks (WSN). Aiming at these problems, a greenhouse environmental parameter monitoring system had been designed based on internet of things technology in this paper. A set of control system with good robustness, strong adaptive ability and small overshoot was set up by combining the fuzzy proportion-integral-derivative (PID) control. The system was composed of a number of independent greenhouse monitoring systems. The server could provide remote monitoring access management services after the collected data were transmitted. The data transmission part of greenhouse was based on ZigBee networking protocol. And the data were sent to intelligent system via gateway connected to the internet. Compared to the classical PID control and fuzzy control, the fuzzy PID control could quickly and accurately adjust the corresponding parameters to the set target. The overshoot was also relatively small. The simulation results showed that the amount of overshoot was reduced 20% compared with classical PID control. 展开更多
关键词 GREENHOUSE environmental monitoring remote service fuzzy PID control
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Mapping epistasis and environment × QTX interaction based on four-omics genotypes for the detected QTX loci controlling complex traits in tobacco 被引量:4
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作者 Liyuan Zhou Ruiyuan Li +6 位作者 Longjiang Fan Yuewei Shi Zhihong Wang Shengdong Xie Yijie Gui Xueliang Ren Jun Zhu 《The Crop Journal》 SCIE CAS 2013年第2期151-159,共9页
Using newly developed methods and software, association mapping was conducted for chromium content and total sugar in tobacco leaf, based on four-omics datasets. Our objective was to collect data on genotype and pheno... Using newly developed methods and software, association mapping was conducted for chromium content and total sugar in tobacco leaf, based on four-omics datasets. Our objective was to collect data on genotype and phenotype for 60 leaf samples at four developmental stages, from three plant architectural positions and for three cultivars that were grown in two locations. Association mapping was conducted to detect genetic variants at quantitative trait SNP(QTS) loci, quantitative trait transcript(QTT) differences,quantitative trait protein(QTP) variability, and quantitative trait metabolite(QTM) changes,which can be summarized as QTX locus variation. The total heritabilities of the four-omics loci for both traits tested were 23.60% for epistasis and 15.26% for treatment interaction.Epistasis and environment × treatment interaction had important impacts on complex traits at all-omics levels. For decreasing chromium content and increasing total sugar in tobacco leaf, six methylated loci can be directly used for marker-assisted selection, and expression of ten QTTs, seven QTPs and six QTMs can be modified by selection or cultivation. 展开更多
关键词 Association MAPPING study Complex trait analysis EPISTASIS effects ENVIRONMENT × treatment INTERACTION Plant architecture control QTX locus MAPPING
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远隔缺血后适应治疗对急性缺血性卒中超时间窗患者临床预后的影响:一项随机对照试验
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作者 袁丹 王莹 +4 位作者 王英鹏 许莉 薛佳 程晶晶 王海鹏 《中国全科医学》 CAS 北大核心 2025年第2期169-174,共6页
背景急性缺血性卒中(AIS)高发,及时恢复脑血流是治疗的关键,超时间窗就诊患者无更多促进脑血流恢复的治疗手段。研究远隔缺血后适应(RIPostC)治疗对AIS超时间窗就诊患者的临床疗效、并发症和预后,具有重要的临床意义。目的探究RIPostC... 背景急性缺血性卒中(AIS)高发,及时恢复脑血流是治疗的关键,超时间窗就诊患者无更多促进脑血流恢复的治疗手段。研究远隔缺血后适应(RIPostC)治疗对AIS超时间窗就诊患者的临床疗效、并发症和预后,具有重要的临床意义。目的探究RIPostC治疗对AIS超时间窗患者干预的影响,为超时间窗就诊的AIS患者寻求安全、有效的脑血流恢复治疗方式。方法本研究采用随机、分组、安慰剂对照法进行试验。选取2021-09-02—2022-08-31于北京航天总医院神经内科病房住院治疗的超溶栓时间窗(发病时间>6 h)的AIS患者为研究对象。依据随机数字表法将患者分为对照组和试验组。试验期+随访期共90 d,均使用同等的一般治疗、脑血管病常规治疗,试验组在此基础上给予RIPostC治疗14 d(28次),对照组给予模拟的RIPostC治疗14 d(28次)。在干预前和干预后30 d、干预后90 d,采用改良Rankin量表(mRS)、美国国立卫生研究院卒中量表(NIHSS)评估两组患者神经功能,简易精神状态检查量表(MMSE)、蒙特利尔认知评估量表(MoCA)评估患者认知功能,工具性日常生活能力量表(IADL)评估日常生活能力,焦虑自评量表(SAS)、抑郁自评量表(SDS)评估精神状态,经颅多普勒超声(TCD)评估脑血流速度,以白介素(IL)-6反映炎症情况。结果122例患者中,最终完成试验及随访99例,其中试验组49例,对照组50例。两组患者性别、年龄、基础疾病(高血压、糖尿病、冠心病)及基线NIHSS评分比较,差异无统计学意义(P>0.05)。重复测量方差分析结果示,时间与组别对MMSE、MoCA、mRS、NIHSS、脑血流速度、IL-6存在交互作用(P<0.05),时间和组别对MMSE、MoCA、NIHSS、脑血流速度、IL-6主效应显著(P<0.05),时间对mRS、SAS、SDS、IADL主效应显著(P<0.05)。试验组干预后30、90 d MMSE、MoCA评分及脑血流速度均高于对照组,mRS、NIHSS评分均低于对照组(P<0.05);试验组干预后30、90 d SDS、IADL评分低于对照组(P<0.05);试验组干预后30 d SAS评分高于对照组,IL-6低于对照组(P<0.05)。99例患者中共有23例患者发生不良反应,其中试验组17例,对照组6例,两组皮肤瘀点、头晕、心慌、胸闷发生率比较,差异无统计学意义(P>0.05);对照组患者皮肤瘀斑发生率[4.00%(2/50)与12.24%(6/49)]、总不良反应发生率[12.00%(6/50)与34.69%(17/49)]低于试验组(P<0.05)。结论RIPostC治疗可降低AIS患者的炎症反应,对神经功能、认知功能抑郁情绪及颅内血流速度可起到积极的改善效果。 展开更多
关键词 急性缺血性卒中 远隔缺血后适应 超时间窗 炎症反应 随机对照试验 重复测量方差分析
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基于动力性模糊控制拖拉机遥控换挡设计研究
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作者 刘九庆 王宇航 项前 《农机化研究》 北大核心 2025年第1期218-225,233,共9页
为实现拖拉机遥控换挡,基于动力性模糊控制换挡设计了电控液压换挡系统,并在AMEsim中搭建仿真模型。根据发动机的调速特性,以油门开度、当前的车速和挡位为输入参数建立动力性换挡模型,并根据驾驶员意图和拖拉机状态建立二级模糊控制器... 为实现拖拉机遥控换挡,基于动力性模糊控制换挡设计了电控液压换挡系统,并在AMEsim中搭建仿真模型。根据发动机的调速特性,以油门开度、当前的车速和挡位为输入参数建立动力性换挡模型,并根据驾驶员意图和拖拉机状态建立二级模糊控制器对动力性换挡策略进行修正。同时,设置工况,在MatLab/Simulink中建立拖拉机传动系统模型,利用AMEsim-Simulink进行联合仿真,得到液压缸活塞杆位移曲线,对可行性进行了验证。对比传统换挡与动力性模糊控制换挡,以离合器冲击度、滑摩功等为控制目标进行仿真分析。结果表明:与传统换挡系统相比所设计的系统控制效果较优,满足拖拉机动力性适应性要求。 展开更多
关键词 拖拉机 模糊控制 遥控换挡 仿真分析
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花卉大棚喷药机器人远程控制系统设计——基于互联网
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作者 陈可飞 王铁广 +3 位作者 李文勤 邢凯 方赛银 李明 《农机化研究》 北大核心 2025年第2期61-67,共7页
针对花卉薄膜大棚传统人工施药效率低、喷洒不均匀且漂浮药物对人体健康造成伤害等问题,设计了一种可实现远程手机控制的悬挂式喷药机器人系统。首先,根据花卉的生长特点和大棚空间结构,在不改变现有大棚结构的前提下,通过增设导轨的方... 针对花卉薄膜大棚传统人工施药效率低、喷洒不均匀且漂浮药物对人体健康造成伤害等问题,设计了一种可实现远程手机控制的悬挂式喷药机器人系统。首先,根据花卉的生长特点和大棚空间结构,在不改变现有大棚结构的前提下,通过增设导轨的方式引入喷药机器人,并依据花卉精准施药的基本要求,在SolidWorks中建模并优化喷药机器人的机械结构;其次,以MCU esp8266模块作为核心控制单元,对继电器、电机、电磁阀和药液泵等硬件进行控制,采用PWM方式调节继电器的导通时间,进而实现喷药机器人根据不同行进速度作业;最后,通过WiFi无线通信模块结合物联网平台设计远程控制APP端,实现喷药机器人启停和环境数据采集等功能。系统测试表明:在无遮挡和有遮挡物环境中,数据传输的成功率分别约为98%和93%,丢包率分别约为1.98%和7%,且喷药机器人在不同的速度下运行稳定。测试结果能够为喷药机器人在大棚内行走稳定性和对花卉自动施药提供技术参考。 展开更多
关键词 花卉大棚 喷药机器人 远程控制 物联网 手机APP
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Analysis of the regional spectral properties in northwestern South China Sea based on an empirical orthogonal function 被引量:3
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作者 Dongyang Fu Yuye Huang +3 位作者 Dazhao Liu Shan Liao Guo Yu Xiaolong Zhang 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2020年第7期107-114,共8页
This study presents an analysis of the spectral characteristics of remote sensing reflectance(Rrs)in northwestern South China Sea based on the in situ optical and water quality data for August 2018.Rrswas initially di... This study presents an analysis of the spectral characteristics of remote sensing reflectance(Rrs)in northwestern South China Sea based on the in situ optical and water quality data for August 2018.Rrswas initially divided into four classes,classes A to D,using the max-classification algorithm,and the spectral properties of whole Rrs were characterized using the empirical orthogonal function(EOF)analysis.Subsequently,the dominant factors in each EOF mode were determined.The results indicated that more than 95%of the variances of Rrs are partly driven by the back-scattering characteristics of the suspended matter.The initial two EOF modes were well correlated with the total suspended matter and back-scattering coefficient.Furthermore,the first EOF modes of the four classes of Rrs(A-D Rrs-EOF1)significantly contributed to the total variances of each Rrs class.In addition,the correlation coefficients between the amplitude factors of class A-D Rrs-EOF1 and the variances of the relevant water quality and optical parameters were better than those of the unclassified ones.The spectral shape of class ARrs-EOF1 was governed by the absorption characteristic of chlorophyll a and colored dissolved organic matter(CDOM).The spectral shape of class B Rrs-EOF1 was governed by the absorption characteristic of CDOM since it exhibited a high correlation with the absorption coefficient of CDOM(ag(λ)),whereas the spectral shape of class C Rrs-EOF1 was governed by the back-scattering characteristics but not affected by the suspended matter.The spectral shape of class D Rrs-EOF1 exhibited a relatively good correlation with all the water quality parameters,which played a significant role in deciding its spectral shape. 展开更多
关键词 northwestern South China Sea remote sensing reflectance empirical orthogonal function analysis ocean color control factors
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Design and implementation of an expert system for remote fault diagnosis in ship lift
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作者 易春辉 李天石 石晓俊 《Journal of Pharmaceutical Analysis》 SCIE CAS 2007年第2期159-163,共5页
In this paper an expert system for remote fault diagnosis in the ship lift was developed by analysis of the fault tree and combination with VPN. The fault tree was constructed based on the operation condition of the s... In this paper an expert system for remote fault diagnosis in the ship lift was developed by analysis of the fault tree and combination with VPN. The fault tree was constructed based on the operation condition of the ship lift. The diagnosis model was constructed by hierarchical classification of the fault tree structure, and the inference mechanism was given. Logical structure of the fault diagnosis in the ship lift was proposed. The implementation of the expert system for remote fault diagnosis in the ship lift was discussed, and the expert system developed was realized on the VPN virtual network. The system was applied to the Gaobaozhou ship lift project, and it ran successfully. 展开更多
关键词 fault diagnosis ship lift fault tree analysis expert control system remote monitoring virtual private network
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Eco-Friendly Selection of Diesel Generator Based on Genset-Synchro Technology for Off-Grid Remote Area Application in the North of Quebec 被引量:2
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作者 Mohamad Issa Jean Fiset +1 位作者 Hussein Ibrahim Adrian Ilinca 《Energy and Power Engineering》 2019年第5期232-247,共16页
For most of their energy requirements, greater part of remote communities and small islands around the world rely on imported fossil fuels. The economical cost of energy is therefore very high not only due to inherent... For most of their energy requirements, greater part of remote communities and small islands around the world rely on imported fossil fuels. The economical cost of energy is therefore very high not only due to inherent cost of fuel, but also due to transportation and due to maintenance costs. One solution for saving fuel in a diesel generator is to allow the engine to operate directly in relation to the request for electrical load at variable speeds. Genset-Synchro Technology has developed an innovative variable speed?generator technology (patent pending) that allows applications where power demand varies widely to benefit from the new technology that maintains constant voltage and frequency while adjusting the generator stator speed to power demand. This paper will present an innovative approach for optimizing the energy production based from the fact that the structure that contains the stator windings of the generator is mounted on roller bearings, which allows its free rotation around the axis of the rotor, consequently stopping the stator structure from being static and aims to minimize the unit cost of electricity. Case study on application in remote area in the north of Quebec is described. A saving of 7%?-?9% on fuel consumption and greenhouse gas (GHG) under low winter ambient temperatures has been registered. 展开更多
关键词 DIESEL GENERATOR remote Areas Fuel Saving Greenhouse Gas Electrical Machines control of Rotor SPEED Variable DIESEL SPEED GENERATOR Total Distortion Harmonics
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Overlooked CO_(2)emissions induced by air pollution control devices in coal-fired power plants 被引量:1
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作者 Pengfei Zhang Kuishuang Feng +3 位作者 Li Yan Yaqin Guo Bei Gao Jiashuo Li 《Environmental Science and Ecotechnology》 SCIE 2024年第1期80-88,共9页
China's efforts to mitigate air pollution from its large-scale coal-fired power plants(CFPPs)have involved the widespread use of air pollution control devices(APCDs).However,the operation of these devices relies o... China's efforts to mitigate air pollution from its large-scale coal-fired power plants(CFPPs)have involved the widespread use of air pollution control devices(APCDs).However,the operation of these devices relies on substantial electricity generated by CFPPs,resulting in indirect CO_(2) emissions.The extent of CO_(2)emissions caused by APCDs in China remains uncertain.Here,using a plant-level dataset,we quantified the CO_(2)emissions associated with electricity consumption by APCDs in China's CFPPs.Our findings reveal a significant rise in CO_(2)emissions attributed to APCDs,increasing from 1.48 Mt in 2000 to 51.7 Mt in 2020.Moreover,the contribution of APCDs to total CO_(2)emissions from coal-fired power generation escalated from 0.12%to 1.19%.Among the APCDs,desulfurization devices accounted for approximately 80%of the CO_(2)emissions,followed by dust removal and denitration devices.Scenario analysis indicates that the lifespan of CFPPs will profoundly impact future emissions,with Nei Mongol,Shanxi,and Shandong provinces projected to exhibit the highest emissions.Our study emphasizes the urgent need for a comprehensive assessment of environmental policies and provides valuable insights for the integrated management of air pollutants and carbon emissions in CFPPs. 展开更多
关键词 Coal-fired power plants CO_(2)emissions Air pollutant control device environmental policy Scenario analysis
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新型环控大棚商品兔舍夏季降温效果的研究
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作者 郭志强 李钰莹 +4 位作者 雷岷 邝良德 郑洁 谢晓红 李丛艳 《家畜生态学报》 北大核心 2024年第6期71-75,共5页
本试验旨在研究新型环控大棚商品兔舍夏季降温效果,选择2880只兔随机分成3个处理,每个处理20个重复,负对照组为开放式兔舍,正对照组为欧式兔舍,试验组为新型环控大棚兔舍。结果显示,夏季大棚兔舍和欧式兔舍平均温度和温湿指数为27.52℃... 本试验旨在研究新型环控大棚商品兔舍夏季降温效果,选择2880只兔随机分成3个处理,每个处理20个重复,负对照组为开放式兔舍,正对照组为欧式兔舍,试验组为新型环控大棚兔舍。结果显示,夏季大棚兔舍和欧式兔舍平均温度和温湿指数为27.52℃、27.62℃和27.11、27.22,较舍外和开放式兔舍分别显著降低了5.71℃、5.61℃和4.06℃、3.96℃(P<0.05),温湿指数分别显著降低了4.51、4.40和3.24、3.13(P<0.05),大棚兔舍降温效果与欧式兔舍差异不显著(P>0.05);大棚兔舍和欧式兔舍舍内风速为1.32 m/s和1.28 m/s,较开放式兔舍分别显著提高了0.57 m/s和0.53 m/s(P<0.05),舍内二氧化碳和氨气浓度虽然有所增加,但与开放式兔舍差异不显著(P>0.05);大棚兔舍和欧式兔舍商品兔采食量、日增重显著高于开放式兔舍(P<0.05),料重比和死亡率显著低于开放式兔舍(P<0.05),商品兔出栏时间较开放式兔舍提前14 d,二者之间差异不显著。结果表明,大棚兔舍可以有效降低夏季兔舍温度,改善兔舍热环境,提高商品兔生产性能,降温效果显著优于开放式兔舍,与欧式兔舍降温效果相当。 展开更多
关键词 大棚兔舍 欧式兔舍 开放式兔舍 降温 生产性能
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Predictive control for greenhouse temperature and humidity and energy optimization by improved NMPC objective function algorithm
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作者 Lina Wang Ying Zhang +2 位作者 Mengjie Xu Qiuhui Liu Binrui Wang 《International Journal of Agricultural and Biological Engineering》 SCIE 2024年第5期128-136,共9页
Persistent low temperatures in autumn and winter have a huge impact on crops,and greenhouses rely on solar radiation and heating equipment to meet the required indoor temperature.But the energy cost of frequent operat... Persistent low temperatures in autumn and winter have a huge impact on crops,and greenhouses rely on solar radiation and heating equipment to meet the required indoor temperature.But the energy cost of frequent operation of the actuators is exceptionally high.The relationship between greenhouse environmental control accuracy and energy consumption is one of the key issues faced in greenhouse research.In this study,a non-linear model predictive control method with an improved objective function was proposed.The improved objective function used tolerance intervals and boundary constraints to optimize the objective evaluation.The nonlinear model predictive control(NMPC)controller design was based on the wavelet neural network(WNN)data-driven model and applied the interior point method to solve the optimal solution of the objective function control,thus balancing the contradiction between energy consumption and control precision.The simulation results showed that the improved NMPC method reduced energy consumption by 21.02%and 9.54%compared with the model predictive control and regular NMPC,which proved the method achieved good results in a low-temperature environment.This research can provide an important reference for the field as it offers a more efficient approach to managing greenhouse climates,potentially leading to substantial energy savings and enhanced sustainability in agricultural practices. 展开更多
关键词 greenhouse environmental control greenhouse energy optimization nonlinear model predictive control objective function improvement
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雷达的腐蚀现状调研及对策分析
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作者 梁元军 朱理智 《现代雷达》 CSCD 北大核心 2024年第5期81-88,共8页
通过调研地面雷达的腐蚀情况,对发现的腐蚀点采用统计分析方法,全面系统地介绍了地面雷达的腐蚀,并针对腐蚀问题和腐蚀规律,提出了腐蚀控制的对策。在腐蚀现状调研分析中,重点介绍了雷达的腐蚀形态、制件暴露环境对腐蚀的影响、腐蚀主... 通过调研地面雷达的腐蚀情况,对发现的腐蚀点采用统计分析方法,全面系统地介绍了地面雷达的腐蚀,并针对腐蚀问题和腐蚀规律,提出了腐蚀控制的对策。在腐蚀现状调研分析中,重点介绍了雷达的腐蚀形态、制件暴露环境对腐蚀的影响、腐蚀主要原因及产生阶段;在腐蚀控制的对策分析中,重点阐述了环境控制设计、密封设计和遮蔽设计的要求及方法。通过数据分析,发现腐蚀规律,制定了结合雷达产品的特点和研发流程进行科学管理的方法体系,提出了树立从方案设计、工程设计到生产制造和使用维护等各阶段进行全方位、全过程和全寿命周期腐蚀综合控制的思想,从顶层完善了雷达产品的腐蚀控制理论体系。 展开更多
关键词 现状 统计分析 腐蚀控制 腐蚀管理 环境控制
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蔬菜大棚温室微气候智能控制系统设计
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作者 徐淑彦 吴刚 李世雄 《中国农机装备》 2024年第12期27-29,共3页
设计了一套针对蔬菜大棚温室微气候的智能控制系统,包括环境监测、智能调控和数据管理三大功能模块,实现对大棚内温度、湿度、光照和CO_(2)浓度的实时监控与自动调节。系统运行测试结果验证了设计的合理性和控制策略的有效性。
关键词 蔬菜大棚 温室微气候 智能控制 环境监测 数据管理
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基于PLC大棚环境监测与控制系统设计
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作者 曹新伟 王瑞 +1 位作者 辜筱淩 焦锐斌 《新疆农机化》 2024年第4期58-61,共4页
本文设计了一种大棚环境监测与控制系统,系统采用数字传感器监测温湿度、光照和CO_(2)浓度等环境参数,通过ZigBee网络发送至中央控制器,经处理后在云平台实现远程监视。通过监测试验与控制评估,证实监测与控制效果良好,该大棚环境监测... 本文设计了一种大棚环境监测与控制系统,系统采用数字传感器监测温湿度、光照和CO_(2)浓度等环境参数,通过ZigBee网络发送至中央控制器,经处理后在云平台实现远程监视。通过监测试验与控制评估,证实监测与控制效果良好,该大棚环境监测与控制系统能为国内设施农业的智能化、节能环保提供参考。 展开更多
关键词 大棚 环境监测 控制 设计
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惯例转移要素分析:来自京津冀地区大气污染治理利基项目间学习的实证研究
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作者 王江 王丽娟 《东北大学学报(社会科学版)》 CSSCI 北大核心 2024年第2期48-57,128,共11页
针对项目间学习的惯例转移进行研究,梳理了惯例转移的概念及内涵,从理论上探讨惯例转移与内外部环境、知识能力以及团队互动之间的相互作用。基于主成分分析和随机森林模型,构建影响惯例转移的重要因素组合,通过对要素的相互作用和关系... 针对项目间学习的惯例转移进行研究,梳理了惯例转移的概念及内涵,从理论上探讨惯例转移与内外部环境、知识能力以及团队互动之间的相互作用。基于主成分分析和随机森林模型,构建影响惯例转移的重要因素组合,通过对要素的相互作用和关系的定量化分析,以评价惯例转移难易程度。通过2015—2019年京津冀大气污染治理惯例转移定量分析,发现惯例转移受不同环境要素影响,并且处在不断进化的学习过程中。知识资源、经济环境对于多数惯例转移是重要的、起作用的要素,易于在其他环境中发生转移,而末端型治理增加了知识资源(通用知识)的转移难度。自然资源和自然环境等要素是惯例转移过程的主要冲突因素,使惯例难以在其他环境中发生转移。 展开更多
关键词 惯例转移 项目间学习 大气污染治理 要素分析 环境要素组合
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风速可调的地空一体化风力灭火遥控机结构设计与性能分析
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作者 杨春梅 赵鑫 +2 位作者 丁禹程 谭少林 闫杰 《林业机械与木工设备》 2024年第9期54-60,共7页
风力灭火遥控机作为地面灭火装备的一种创新形式,具备机动性强、远程操作、快速响应等特点,能够在复杂的火情环境中灵活作业,大大提高了灭火效率和安全性。为探讨风力灭火遥控机在应对森林和草原地表火灾地空一体化监测系统中的角色与作... 风力灭火遥控机作为地面灭火装备的一种创新形式,具备机动性强、远程操作、快速响应等特点,能够在复杂的火情环境中灵活作业,大大提高了灭火效率和安全性。为探讨风力灭火遥控机在应对森林和草原地表火灾地空一体化监测系统中的角色与作用,对风力灭火遥控机进行结构设计,分析旋转开合结构的安装位置和开口大小对出口风速的影响。利用Fluent软件对风力灭火筒进行流体仿真,结合Design Expert软件对仿真数据进行处理,建立了位置S和开口大小d对出口平均风速和出口最大风速的响应曲面和二次模型。结果表明,安装位置和开口大小均为出口风速的重要影响因素,当风筒入口风速设定为70 m/s、旋转开合结构开口大小为30 mm且安装在位置5处时,出口平均风速和出口最大风速达到最大,分别为97.7551 m/s和290.001 m/s。相较于开口大小,安装位置对出口平均风速和出口最大风速的影响更大,且安装位置越靠近风筒出口处风力灭火机的灭火性能越好。 展开更多
关键词 火灾地空一体化监测 流量调节装置 风力灭火遥控机 结构设计与性能分析
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