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Revising Nitrogen Recommendations for Wheat in Response to the Need for Support of Variable-Rate Nitrogen Application 被引量:3
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作者 D. W. Franzen G. Endres +3 位作者 R. Ashley J. Staricka J. Lukach K. McKay 《Journal of Agricultural Science and Technology(A)》 2011年第1X期89-95,共7页
Sampling studies in North Dakota conducted from 1994 to 2003 showed that variable-rate N application could be practically directed with zone soil sampling. Results from variable-rate N studies using zone soil sampling... Sampling studies in North Dakota conducted from 1994 to 2003 showed that variable-rate N application could be practically directed with zone soil sampling. Results from variable-rate N studies using zone soil sampling were often less than rewarding due in part to the use of a whole-field predicted yield-based formula for developing the N recommendation in each zone. Nitrogen rate studies on spring wheat and durum were established in 2005 through 2009 with the objective to reexamine N recommendations and construct a new system if necessary. The results of the study and archived wheat N response data showed that the state should be divided into three separate N response regions. Within each region historic yields from low to high productivity were defined. The gross N rate was determined using the return-to-N concept developed in the US corn-belt states but with additional consideration for wheat protein value The gross N rate is then modified by credits for previous crop, soil test N from zone soil sampling, tillage systems, excessive straw from the previous year, relative susceptibility to nitrate leaching or denitrification. Finally, the user is encouraged to use common sense and consider whether particular fields have characteristics that require more or less N fertilizer than suggested by the recommendation formulas. 展开更多
关键词 variable-rate fertilizer application nitrogen fertilizer fertilizer recommendations spring wheat durum wheat
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New algorithm for variable-rate linear broadcast network coding 被引量:1
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作者 夏寅 张惕远 黄佳庆 《Journal of Central South University》 SCIE EI CAS 2011年第4期1193-1199,共7页
To adjust the variance of source rate in linear broadcast networks, global encoding kernels should have corresponding dimensions to instruct the decoding process. The algorithm of constructing such global encoding ker... To adjust the variance of source rate in linear broadcast networks, global encoding kernels should have corresponding dimensions to instruct the decoding process. The algorithm of constructing such global encoding kernels is to adjust heterogeneous network to possible link failures. Linear algebra, graph theory and group theory are applied to construct one series of global encoding kernels which are applicable to all source rates. The effectiveness and existence of such global encoding kernels are proved. Based on 2 information flow, the algorithm of construction is explicitly given within polynomial time O(|E| |T|.ω^2max), and the memory complexity of algorithm is O(|E|). Both time and memory complexity of this algorithm proposed can be O(ωmax) less than those of algorithms in related works. 展开更多
关键词 network coding variable-rate linear broadcast heterogeneous network code construction algorithm
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A unified result for variable-rate linear network coding 被引量:1
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作者 马松雅 卓新建 +2 位作者 郭钦 罗明星 杨义先 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2010年第5期657-660,共4页
Fong et al.analyzed variable-rate linear network coding for linear broadcast.However,the authors didn't investigate it for the other three types of linear network codes.In this paper,by simple and clear proofs,it ... Fong et al.analyzed variable-rate linear network coding for linear broadcast.However,the authors didn't investigate it for the other three types of linear network codes.In this paper,by simple and clear proofs,it is found that there are similar results for variable-rate linear generic and linear dispersion if the field size is large enough.It means that linear generics and linear dispersions of different dimensions can be implemented on the same network,while each non-source node is required to store only one copy of the local encoding kernel within a session.Moreover,an example is given to show that there isn't a similar result for linear multicast. 展开更多
关键词 variable-rate linear generic linear dispersion linear broadcast linear multicast
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Design and Experiment of Slave Computer Control System for Applying Variable-rate Liquid Fertilizer
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作者 Zhang Ying-zi Chen Hai-tao +4 位作者 Hou Shou-yin Ji Wen-yi Ouyang Bin-lin Dun Guo-qiang Zhang Ji-cheng 《Journal of Northeast Agricultural University(English Edition)》 CAS 2015年第2期73-79,共7页
In order to increase the applying rate of liquid fertilizer and reduce environmental pollution, a slave computer control system for applying variable-rate liquid fertilizer was designed. The system used SMC as core pr... In order to increase the applying rate of liquid fertilizer and reduce environmental pollution, a slave computer control system for applying variable-rate liquid fertilizer was designed. The system used SMC as core processor and electrically controlled pressure regulator as execution component. The characteristic equation of the system was obtained by using classical control theory. Results indicated that the characteristic equation met the requirements of routh-criterion, which indicated the working process of the system was stable. Performance of the slave computer was verified via bench tests. Results demonstrated that there was no significant influence on the response from interclass error. The fertilization error was less than 0.9, and the fertilization accuracy was larger than 97%. The liquid fertilizer emitted by the fertilizing devices had no significant difference in uniformity, which met the demands of the slave computer control system for applying variable-rate liquid fertilizer. 展开更多
关键词 variable-rate fertilization control system mathematical model
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Generalized Minimum Rank Distance of Variable-Rate Linear Network Error Correction Codes
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作者 ZHOU Hang 《Wuhan University Journal of Natural Sciences》 CAS CSCD 2021年第1期19-23,共5页
By extending the notion of the minimum distance for linear network error correction code(LNEC), this paper introduces the concept of generalized minimum rank distance(GMRD) of variable-rate linear network error correc... By extending the notion of the minimum distance for linear network error correction code(LNEC), this paper introduces the concept of generalized minimum rank distance(GMRD) of variable-rate linear network error correction codes. The basic properties of GMRD are investigated. It is proved that GMRD can characterize the error correction/detection capability of variable-rate linear network error correction codes when the source transmits the messages at several different rates. 展开更多
关键词 network error correction code error pattern generalized minimum distance variable-rate
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Discussion on the Design and Optimization Strategy of Automatic Sprinkler Fire Extinguishing in Building Fire Protection Systems
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作者 Gaojie Liu 《Journal of Architectural Research and Development》 2025年第6期98-106,共9页
This paper focused on the design and optimization of automatic sprinkler fire extinguishing systems in building fire protection.It was emphasized the importance of considering various factors in design,such as fire ri... This paper focused on the design and optimization of automatic sprinkler fire extinguishing systems in building fire protection.It was emphasized the importance of considering various factors in design,such as fire risk assessment and space utilization.Optimization strategies include enhancing water and energy efficiency,using ecofriendly materials,and smart monitoring.Practical implementation and validation in different building types were presented,along with performance benchmark analysis.Balancing fire safety and resource utilization is crucial,and future research in AI driven tuning and nano materials was promising. 展开更多
关键词 Automatic sprinkler system Optimization strategy Building fire protection
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喷灌施肥系统水力耦合模型构建及压力分布影响因素研究
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作者 涂琴 汤攀 易萌 《节水灌溉》 北大核心 2026年第1期9-16,共8页
为了探究施肥泵运行、喷头配置及工作参数等因素对喷灌施肥系统水力性能的影响,将水泵性能曲线、施肥泵吸肥模型及多口出流管道水力计算模型相结合,建立轻小型喷灌施肥系统水力耦合模型。首先,基于试验数据,提出了以入口压力、入口流量... 为了探究施肥泵运行、喷头配置及工作参数等因素对喷灌施肥系统水力性能的影响,将水泵性能曲线、施肥泵吸肥模型及多口出流管道水力计算模型相结合,建立轻小型喷灌施肥系统水力耦合模型。首先,基于试验数据,提出了以入口压力、入口流量和母液浓度为自变量的比例施肥泵吸肥模型。再与退步法管道水力计算方法相结合,首次建立了水泵-施肥泵-灌溉管道-喷头水动力耦合计算模型。针对该模型的强非线性特性,采用遗传算法(GA)进行求解。以配备50ZB-30Q水泵、摇臂式喷头10PY2H及比例施肥泵D8R的系统为例进行仿真,分析施肥泵运行、喷头数、喷头工作压力、喷嘴直径、母液浓度等因素对管道压力分布的影响。结果表明:与清水灌溉相比,接入施肥泵后不同喷头数配置下机组单位能耗平均升高了25%;清水施肥与清水灌溉相比,管道压力变化范围总体缩小,可能与比例施肥泵周期运行有关;喷头数过多(11个以上)容易引起管道压力状态突变;低工作压力(0.22 MPa)则会增大系统对水力干扰的敏感性;增大喷嘴直径(5.5 mm)可有效抑制管道压力波动;施肥浓度增加时,多喷头数下的管道压力显著提高。各因素的影响表现出强非线性。研究表明,在喷灌施肥系统的优化、评价与精确控制中,建议优先考虑系统的水力稳定性。 展开更多
关键词 变量喷灌施肥系统 水力耦合模型 管道压力 喷灌 遗传算法 施肥泵
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射流脉冲喷头内驱动结构优化与水力性能
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作者 王新坤 武文婧 +1 位作者 孟天舒 杨凡 《农业工程学报》 北大核心 2026年第2期150-156,共7页
针对摇臂式喷头应用过程中存在的射流破碎不充分、水量分布不均、摇臂驱动装置复杂等问题,该研究设计了一种凸起高度4.7 mm、宽度8 mm、锥角120°的棱锥体副喷嘴内驱动射流脉冲喷头。基于不同结构参数的脉冲水力性能响应特征,开展... 针对摇臂式喷头应用过程中存在的射流破碎不充分、水量分布不均、摇臂驱动装置复杂等问题,该研究设计了一种凸起高度4.7 mm、宽度8 mm、锥角120°的棱锥体副喷嘴内驱动射流脉冲喷头。基于不同结构参数的脉冲水力性能响应特征,开展了内驱动棱锥体凸起高度、宽度、锥角的三因素三水平正交试验,制作了最优结构参数的样机,与同条件摇臂式喷头进行水力性能对比试验。试验结果表明,在0.20~0.35 MPa压力范围内,内驱动射流脉冲喷头的出口射流峰谷波动明显,主喷嘴能够确保喷头射程及远处喷洒水量,副喷嘴破碎射流并驱动喷头旋转,增加中近距离的喷洒水量,改善喷洒水量分布;水量近似“梯形”分布,远处水量分布与同类型产品接近,中间与近距离水量分布形态较好;流量减小14%~19.3%,平均喷灌强度下降11.6%~16.6%。整体性能优于同类产品,低压状态下的表现尤为突出,符合喷灌技术低压喷洒的发展趋势,可为射流脉冲喷头的新型驱动结构研究与应用提供参考。 展开更多
关键词 喷头 射流脉冲 内驱动 结构优化 水力性能
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南疆地区小麦、玉米水肥一体化微喷灌技术集成与应用研究
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作者 袁小伟 金若成 +4 位作者 王向未 郑楠 赵黎炜 阿德力·阿力甫 吕慧捷 《农业科技与装备》 2026年第1期77-79,共3页
针对南疆地区小麦、玉米种植中水资源短缺、肥料利用率低及土壤盐碱化等问题,研究构建了适用于当地的水肥一体化微喷灌技术体系。该体系集成微喷灌系统设计、精准灌溉制度、适宜肥料配置及配套监测与耕作技术。应用结果表明,该技术能显... 针对南疆地区小麦、玉米种植中水资源短缺、肥料利用率低及土壤盐碱化等问题,研究构建了适用于当地的水肥一体化微喷灌技术体系。该体系集成微喷灌系统设计、精准灌溉制度、适宜肥料配置及配套监测与耕作技术。应用结果表明,该技术能显著提高水肥利用效率,减轻土壤盐渍化,为南疆地区小麦—玉米一年两熟模式提供可持续的水肥管理支持。 展开更多
关键词 小麦 玉米 水肥一体化 微喷灌技术 南疆地区
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基于AquaCrop模型的内蒙古半干旱区紫花苜蓿灌溉制度优化
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作者 门立雪 彭致功 +5 位作者 钟韵 张宝忠 田德龙 朱士江 孙岩颖 任闰巳 《节水灌溉》 北大核心 2026年第2期101-107,共7页
为提升内蒙古半干旱区人工牧草的水分利用效率,以土默特左旗喷灌紫花苜蓿为研究对象,利用经校验的AquaCrop模型模拟16种不同灌溉制度情景下紫花苜蓿产量、耗水量(ET)和水分生产率(WUE)的响应规律。结果表明:经校验后的模型能很好模拟紫... 为提升内蒙古半干旱区人工牧草的水分利用效率,以土默特左旗喷灌紫花苜蓿为研究对象,利用经校验的AquaCrop模型模拟16种不同灌溉制度情景下紫花苜蓿产量、耗水量(ET)和水分生产率(WUE)的响应规律。结果表明:经校验后的模型能很好模拟紫花苜蓿产量(精度>95%)和生育期内土壤墒情的变化过程(R^(2)>0.762,RMSE<1.927%,NRMSE<0.09,EF>0.670);利用经校验模型模拟不同情景下紫花苜蓿的水分与产量响应关系表明,在第一(三)茬与第二(四)茬的土壤水分适宜灌溉下限分别为60%FC、65%FC时实现WUE和产量的双重最优,在此优化灌溉制度下灌溉量为360 mm、耗水量为599 mm、产量达13.645 t/hm^(2)、整体WUE达2.278 kg/m3,较现状增产19%且WUE提高17%。根据苜蓿不同茬口对水分利用需求,采用适宜土壤水分灌溉下限确定灌溉时机,利于不同水文年下苜蓿水分高效利用与多茬次均衡增产的协同优化,为内蒙古半干旱区紫花苜蓿精细化灌溉管理提供了基础数据支撑。 展开更多
关键词 紫花苜蓿 喷灌 AquaCrop模型 产量 灌溉制度
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基于YOLO11n的非机动车辆轻量化目标检测模型
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作者 汪立远 罗亚波 +1 位作者 张峰 黄随 《半导体光电》 北大核心 2026年第1期131-139,共9页
针对洒水车智能喷洒中非机动车辆检测算法复杂度高、多尺度目标检测困难等问题,提出一种基于YOLO11n的轻量化目标检测模型。基于YOLO11n模型,设计了轻量化多尺度骨干网络,将传统下采样模块替换为轻量级自适应提取模块。提出多尺度卷积模... 针对洒水车智能喷洒中非机动车辆检测算法复杂度高、多尺度目标检测困难等问题,提出一种基于YOLO11n的轻量化目标检测模型。基于YOLO11n模型,设计了轻量化多尺度骨干网络,将传统下采样模块替换为轻量级自适应提取模块。提出多尺度卷积模块C3k2-MSCB,并引入大核注意力机制改进C2PSA,以减少模型的参数量,提升模型对多尺度信息的检测能力。使用基于卷积神经网络的跨尺度特征融合模块替换原模型颈部网络,进一步缩小模型大小,提高检测效率。实验结果表明,在自建的非机动车辆数据集上,相较于基准模型,改进的YOLO11n模型的的参数量、GFLOPs和模型大小分别降低了46.3%,20.3%和42.9%,同时mAP@50提升了0.3%,为洒水车智能喷洒系统提供了可靠的支持。 展开更多
关键词 YOLO11n 主干网络 轻量化 多尺度 洒水车 非机动车辆
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基于博弈论融合权重TOPSIS的智慧喷灌效益评价及关键因子诊断分析
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作者 向宇轩 赵鑫 +6 位作者 崔宁博 邢立文 姜守政 王智慧 朱国宇 吴宗俊 张敏 《节水灌溉》 北大核心 2026年第3期76-85,共10页
针对大田作物智慧喷灌综合效益难以精确量化的实践难题,本研究引入博弈论综合AHP法(Analytic Hierarchy Process)和熵权法的主客观权重,建立改进的TOPSIS模型,以河北省宁晋县大曹庄农场喷灌小麦节水增产试验区为案例,验证模型有效性和... 针对大田作物智慧喷灌综合效益难以精确量化的实践难题,本研究引入博弈论综合AHP法(Analytic Hierarchy Process)和熵权法的主客观权重,建立改进的TOPSIS模型,以河北省宁晋县大曹庄农场喷灌小麦节水增产试验区为案例,验证模型有效性和稳定性并对影响智慧喷灌综合效益的关键因子进行了识别分析。结果表明:基于博弈论融合权重的TOPSIS模型克服了熵权法对极端数值的敏感性和AHP法的主观性,显著提升了评价结果的区分度与稳健性。分析显示T2处理(返青–拔节期25%亏水)在增产率、水分利用效率和土壤健康等方面表现均衡,被评为最优模式;斯皮尔曼相关性分析进一步表明,增产率(ρ=0.988)、水分利用效率(ρ=0.875)和土壤微生物代谢强度(ρ=0.855)是系统综合效益的关键驱动因子,而过度节水(>30%)则导致效益显著下降。本研究为华北平原智慧喷灌技术模式选择提供了科学的决策依据和方法,对推动华北平原农业水资源精准配置与高效利用具有重要参考价值。 展开更多
关键词 博弈论组合赋权 智慧喷灌 关键因子诊断 综合效益评价
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基于产量、品质及水肥利用效率的核桃水肥耦合方案寻优
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作者 叶尔扎提·叶尔哈孜 夏邱浩 +6 位作者 陈天财 Mian Muhammad Ahmed 吾尔肯·努尔达吾列提 张锐 杨桂燕 丁洋洋 郭众仲 《果树学报》 北大核心 2026年第2期424-438,共15页
【目的】探究核桃产量和水分利用率的水肥耦合效应并获得最佳水肥方案。【方法】以新疆生产建设兵团第一师阿拉尔市三团温185核桃品种为试材,通过开展田间小区水肥耦合试验,设2个灌水水平,分别为W1:500 m^(3)·666.7 m^(-2),W2:400 ... 【目的】探究核桃产量和水分利用率的水肥耦合效应并获得最佳水肥方案。【方法】以新疆生产建设兵团第一师阿拉尔市三团温185核桃品种为试材,通过开展田间小区水肥耦合试验,设2个灌水水平,分别为W1:500 m^(3)·666.7 m^(-2),W2:400 m^(3)·666.7 m^(-2),以产量为目标设置250、300和350 kg·666.7 m^(-2)3个梯度施肥量,共计6个水肥耦合处理,以农户常规管理为对照(CK),分析不同水肥耦合方案对核桃果实品质、产量及水肥利用率的影响,通过回归模型进行求解。【结果】核桃产量、水分利用率和肥料偏生产力随着水肥二因子增加呈先升后降趋势;灌水对核桃产量和水分利用率的影响程度小于施肥;水肥耦合对核桃产量和水分利用率有正交互作用。【结论】核桃生育期最佳水肥方案为灌水量498.12 m^(3)·666.7 m^(-2),施肥量139.72 kg·666.7 m^(-2)。在此方案下,核桃的脂肪含量、产量、水分利用效率和肥料偏生产力分别达到59.08%、410.73 kg·666.7 m^(-2)、0.75 kg·m^(-3)和44.44 kg·m^(-3)。 展开更多
关键词 核桃 微喷灌 水肥耦合 水分利用效率 肥料偏生产力
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不同灌溉方式对麦田土壤呼吸及碳平衡的影响
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作者 杨明达 张素瑜 +7 位作者 黄洁 李帅 王玉梅 郑东方 杨慎骄 吕仿杰 陈金平 马守田 《麦类作物学报》 北大核心 2026年第3期374-383,共10页
为明确不同灌溉方式对麦田生态系统碳平衡的影响,筛选适宜华北平原小麦生产的节水、减排与增产协同的高效灌溉模式,设置传统地面灌溉(FI)、隔畦交替灌溉(ABI)和微喷灌(MSI)3种灌溉方式,并在微喷灌条件下设置20 mm(MSI20)、30 mm(MSI30)... 为明确不同灌溉方式对麦田生态系统碳平衡的影响,筛选适宜华北平原小麦生产的节水、减排与增产协同的高效灌溉模式,设置传统地面灌溉(FI)、隔畦交替灌溉(ABI)和微喷灌(MSI)3种灌溉方式,并在微喷灌条件下设置20 mm(MSI20)、30 mm(MSI30)和40 mm(MSI40)微喷定额,探究不同灌溉方式和微喷量对麦田土壤呼吸、农田生态系统净碳值和土壤碳排放效率的影响。结果表明,与FI处理相比,MSI处理均能降低小麦抽穗之前土壤的呼吸速率,提高灌浆阶段土壤的呼吸速率;ABI处理的灌溉量较低,其土壤呼吸速率整体偏低。各处理灌溉耗电碳排放量占生产资料碳排放总量的60.3%~75.8%,是灌溉农业投入中的主要碳源。与FI处理相比,MSI20和MSI30处理两年的平均小麦产量分别提高6.5%和8.1%,且在2022—2023年其麦田生态系统净碳值分别提高20.2%和15.5%,土壤碳排放效率分别提高9.4%和2.9%;虽然ABI处理获得相近甚至更高的农田生态系统净碳值和土壤碳排放效率,但其产量较FI处理降低5.1%~9.8%。随微喷量的提高,冬小麦的产量未显著增加,并且在灌浆中期降雨较多情况下,较高微喷量(2022—2023年MSI40处理)冬小麦的产量、麦田生态系统净碳值和土壤碳排放效率均显著降低。本试验条件下,综合考虑节水、减排、产量及环境效益,微喷灌定额20 mm是最优的灌溉管理模式。 展开更多
关键词 小麦 灌溉方式 微喷灌 生产资料碳排放量 净碳值 碳排放效率
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不同主副喷嘴孔径比下射流撞击喷头水力性能
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作者 李冰玉 蒋跃 王路雅 《排灌机械工程学报》 北大核心 2026年第2期208-216,共9页
为了省去部分摇臂式喷头在中低压下所需加装的额外散水装置,基于主副射流非对称撞击模式设计了一种射流撞击喷头.通过水力性能试验获得中压与低压下不同孔径比(1.00,1.33,1.66,2.00)的射流撞击喷头与射流不撞击喷头水量分布和射程,计算... 为了省去部分摇臂式喷头在中低压下所需加装的额外散水装置,基于主副射流非对称撞击模式设计了一种射流撞击喷头.通过水力性能试验获得中压与低压下不同孔径比(1.00,1.33,1.66,2.00)的射流撞击喷头与射流不撞击喷头水量分布和射程,计算获得组合均匀系数,结合高速摄影(high-speed photographic,HSP)试验捕捉的图像测量射流破碎长度变化,采用非线性曲线拟合孔径比、主喷嘴出口截面直径、射流破碎长度、工作压力与射程关系.结果表明:与射流不撞击喷头相比,射流撞击喷头呈现更平缓水量分布趋势;随射流撞击组合均匀性提高,射程降低;射流破碎长度随孔径比增加而增加,印证水力性能表现出的射程随孔径比增加而增加现象;根据所得综合评分,当主副喷嘴孔径比为2.00时,射流撞击喷头适用于中低压灌溉工作.该结果为非对称射流撞击喷头的研究提供了理论依据. 展开更多
关键词 射流撞击 喷头 孔径比 CRITIC权重法 高速摄影 水力性能
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某核电厂安全壳喷淋泵轴承温度高的根本原因分析
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作者 薛军军 李建业 +2 位作者 任松涛 张军 李春秋 《机械管理开发》 2026年第2期219-220,283,共3页
对某核电厂2号机组2号安全壳喷淋泵(以下称“安喷泵”)执行定期试验时对轴承温度高问题进行回顾,以设备结构特点、故障模式为切入点,对可能引起轴承温度高的原因逐一分析,排除干扰因素,找到问题的直接原因、根本原因。转动设备轴承温度... 对某核电厂2号机组2号安全壳喷淋泵(以下称“安喷泵”)执行定期试验时对轴承温度高问题进行回顾,以设备结构特点、故障模式为切入点,对可能引起轴承温度高的原因逐一分析,排除干扰因素,找到问题的直接原因、根本原因。转动设备轴承温度异常问题常规经验是润滑剂不足导致,但是此次处理该问题的经验说明,润滑剂过多也是引起轴承温度异常的重要原因。为后续该型设备出现类似问题提供宝贵的处理经验。 展开更多
关键词 安全壳喷淋泵 轴承 温度 异常 润滑
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商业会展综合建筑中喷头选择及设置问题探讨
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作者 李国顺 《工程建设与设计》 2026年第1期66-68,共3页
以苏州青苔国际工业设计村三期会展项目为例,从喷头类型、喷头动作温度、喷头结构形式和安装方式、喷头出水口径及喷头响应时间等方面介绍了喷头的选择方法。针对建筑内部场所功能区不同的特点,介绍了场所内喷头设置情况,着重分析了建... 以苏州青苔国际工业设计村三期会展项目为例,从喷头类型、喷头动作温度、喷头结构形式和安装方式、喷头出水口径及喷头响应时间等方面介绍了喷头的选择方法。针对建筑内部场所功能区不同的特点,介绍了场所内喷头设置情况,着重分析了建筑内部特殊区域喷头的设置要求,强调结合建筑造型、净空高度及危险等级选择合适的喷头设置方案。 展开更多
关键词 综合建筑 喷头 湿式系统 闭式系统 设置场所
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饲料厂粉碎间粉尘防爆升级改造技术实践
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作者 安发明 《电气防爆》 2026年第1期19-21,共3页
通过对粉碎间防爆区域界定、粉碎机及附属设备防爆升级、火花探测装置选型安装、喷淋灭火系统联动设计等关键技术实践应用的分析,解决了粉碎作业中的粉尘积聚与火花引爆风险,为饲料厂同类场所的安全改造提供参考。
关键词 饲料厂 粉碎间 粉尘防爆 火花探测 喷淋灭火 设备升级
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Tree-Temperature Monitoring for Frost Protection of Orchards in Semi-Arid Regions Using Sprinkler Irrigation 被引量:15
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作者 Ali Asghar Ghaemi Mohammad Rafie Rafiee Ali Reza Sepaskhah 《Agricultural Sciences in China》 CSCD 2009年第1期98-107,共10页
Automated over-tree sprinkler irrigation systems were developed and tested in two orchards located in two separate locations in southern Iran (a 0.17 ha peach orchard and a 0.24 ha orange orchard) to protect peach b... Automated over-tree sprinkler irrigation systems were developed and tested in two orchards located in two separate locations in southern Iran (a 0.17 ha peach orchard and a 0.24 ha orange orchard) to protect peach blossoms and orange trees leaves and fruits from low temperature damage. The experiment used a system that monitored the trees and air temperatures using two thermistors. The water application rate by the irrigation system was determined by an energy balance as implemented by the software FROSTPRO, In the peach orchard, the system was tested during three frost events during the spring of 2003 and three other events during the spring of 2004. The system successfully kept peach flowers above the critical temperature, i.e., -4.0℃ in spring 2004 (control block -4.12℃, and sprinkled block +0.5℃) during all events. Similar results were obtained in the orange orchard during three frost events in the winter of 2004, during which the tree temperatures were at least 2.5℃ above the critical temperature. Results from field tests show that the system can effectively protect the peach blossoms from damage. Determination done after the frost events showed a 12% blossom kill in the sprinkled blocks while in the unsprinkled control block a 41.5% blossom kill. Calculations indicated that when using variable application rates, the amount of water used can be reduced by 54.3%. Spatial distribution of minimum temperatures during the three frosts was also studied in Jahrom, Iran. Results showed a significant temperature control in the experimental block, especially in the central part of the orchard, but the block margins (about 3.6% of the total area) were at the risk of low temperature due to the wind drift effects. 展开更多
关键词 AUTOMATED sprinkler irrigation FROSTPORO frost protection peach orchard orange orchard
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Experimental Investigation of Soil Evaporation and Evapotranspiration of Winter Wheat Under Sprinkler Irrigation 被引量:5
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作者 YU Li-peng HUANG Guan-hua +2 位作者 LIU Hai-jun WANG Xiang-ping WANG Ming-qiang 《Agricultural Sciences in China》 CAS CSCD 2009年第11期1360-1368,共9页
Sprinkler irrigation is one of the typical irrigation technologies used for the winter wheat-summer maize double cropping system in the North China Plain. To evaluate the evapotranspiration (ET) of winter wheat unde... Sprinkler irrigation is one of the typical irrigation technologies used for the winter wheat-summer maize double cropping system in the North China Plain. To evaluate the evapotranspiration (ET) of winter wheat under sprinkler irrigation in Beijing area, field experiments were conducted in growing seasons through 2005-2008, in the experimental station located in Tongzhou County, Beijing, China, with different irrigation depths. Results indicated that a relatively large variation of soil water content occurred within 0-40 cm soil layer. The seasonal ET of winter wheat generally increased with increasing irrigation amount, while the seasonal usage of soil water had a negative relationship with irrigation amount. Soil evaporation (Es) was about 25% of winter wheat ET during the period from reviving to maturity. Es increased while Es/ET decreased with increasing irrigation amount. Sprinkler irrigation scheduling with relatively large irrigation quota and low irrigation frequency can reduce Es and promote the irrigation water use efficiency. 展开更多
关键词 sprinkler irrigation winter wheat EVAPOTRANSPIRATION soil evaporation soil water distribution
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