李彬,李娜,李端明,龔詩(shī)雯
考慮水頭損失的管道灌溉分水口輪灌分組優(yōu)化模型
李彬1,李娜2,李端明2,龔詩(shī)雯2
(1.揚(yáng)州大學(xué) 電氣與能源動(dòng)力工程學(xué)院,江蘇 揚(yáng)州 225127;2.中國(guó)灌溉排水發(fā)展中心,北京 100054)
【】?jī)?yōu)化灌溉系統(tǒng)中分水口輪灌分組的灌溉制度,在滿足流量要求的條件下節(jié)約電能。提出了在考慮水頭損失時(shí)不同分水口狀態(tài)與管道進(jìn)口壓力的關(guān)系模型,該模型利用分水口開關(guān)0,1狀態(tài)作為自變量,從管道末端起利用推導(dǎo)的遞推公式求出管道進(jìn)水口的等效水頭損失系數(shù)。依據(jù)該模型,在定流量分組輪灌優(yōu)化中得到為使分組輪灌功率最小的目標(biāo)函數(shù)。利用遺傳算法對(duì)上述問題進(jìn)行了優(yōu)化求解,并給出了編碼方案。在分水口等間隔布置時(shí),輪灌分組按輪灌分組數(shù)等間隔安排所需功率最小,優(yōu)化后的水頭損失系數(shù)可以減小到?jīng)]有優(yōu)化前的0.772倍。本研究模型不僅適用于恒定流量的組合優(yōu)化,也可應(yīng)用于不同分水口的所需水量不同的隨機(jī)灌溉以及恒壓供水的優(yōu)化中。
輪灌;水頭損失;模型;遺傳算法
節(jié)水灌溉的實(shí)現(xiàn)途徑主要有2種,一是研究植物需水量與產(chǎn)量的關(guān)系,從而確定植物最優(yōu)灌溉方式[1-2];二是改變傳統(tǒng)明渠灌溉為管道灌溉方式,其利用管道將水直接輸送到田間進(jìn)行灌溉,有效地避免了水在渠道內(nèi)發(fā)生的滲漏及蒸發(fā)損失[3]。同時(shí),利用管道輸送水到田間,不需要占用農(nóng)田,節(jié)約了寶貴的土地資源,有效提高了灌溉的效率。隨著自動(dòng)化技術(shù)的發(fā)展和控制系統(tǒng)的成本下降,灌溉控制也越精細(xì),如通過智能閥門或智能閘門可以實(shí)現(xiàn)灌溉系統(tǒng)最末端的放水口的控制?!狙芯恳饬x】在管道灌溉自動(dòng)化控制系統(tǒng)的基礎(chǔ)上,研究末端放水口的優(yōu)化控制策略,對(duì)于降低管道水頭損失、提高灌溉效率具有重要意義。
【研究進(jìn)展】文獻(xiàn)[3]設(shè)計(jì)了一種基于物聯(lián)網(wǎng)和云架構(gòu)的渠灌閘門遠(yuǎn)程智能控制系統(tǒng),其核心部件是末端的智能一體化閘門,實(shí)現(xiàn)了農(nóng)田明渠灌溉的精準(zhǔn)化控制。文獻(xiàn)[4]根據(jù)管網(wǎng)數(shù)學(xué)模型研究了低壓管道灌溉的合適規(guī)模。根據(jù)管道灌溉實(shí)際應(yīng)用情況來看,管道輸水比混凝土襯砌明渠輸水可有效減少蒸發(fā)損失約5%的水量。但是,由于管道灌溉增加了水頭損失,實(shí)際用電量比明渠灌溉增加了。同時(shí),在管道灌溉中為了降低成本,縮小了輸水管道管徑,更加大了水頭損失,而水頭損失的存在也使首端和末端分水口壓力相差大,造成流量偏差大、灌溉不均勻。實(shí)際灌溉中通常采用輪灌方式,可以集中流量,縮小灌水延續(xù)時(shí)間,及時(shí)滿足作物需水要求。而輪灌的分組方法不同,所帶來的運(yùn)行成本也不同。程毅強(qiáng)[5]討論了2種輪灌分組方式,即集中式和半集中分組方式,通過水力計(jì)算,得出半集中方式設(shè)計(jì)揚(yáng)程較小,管道壓力也相對(duì)均勻,整體效果比集中式好;實(shí)踐中普遍采用的輪灌分組方法是根據(jù)經(jīng)驗(yàn)事先人為決定幾種灌溉模式,再對(duì)上述模式分析比較[6],這種方法受人為因素大,很難保證最優(yōu)結(jié)果。高偉增等[7-8]采用遺傳算法對(duì)下級(jí)渠道的輪灌時(shí)間和輪灌周期進(jìn)行優(yōu)化,減少了輸水損失。同樣Anwar等[9-10]利用遺傳算法實(shí)現(xiàn)了以減少棄水和減少灌溉時(shí)間為目標(biāo)的優(yōu)化,得到了較好的效果;Kaur等[11]通過多目標(biāo)優(yōu)化,較好地解決了不同需水灌溉、長(zhǎng)周期、方便用戶操作等問題,而更復(fù)雜的灌溉優(yōu)化為植物生長(zhǎng)周期的灌溉制度的優(yōu)化[12-13]。
【切入點(diǎn)】當(dāng)考慮水頭損失時(shí),管道灌溉系統(tǒng)中的輪灌分組數(shù)、不同組內(nèi)的分水口輪灌組合對(duì)管道進(jìn)口壓力的要求不同,體現(xiàn)在對(duì)灌溉的功率需求也不同;不同分水口之間的壓力、流量不同,從而影響灌溉的均勻性?!緮M解決的關(guān)鍵問題】為此,本文建立不同分水口狀態(tài)與管道進(jìn)口壓力的關(guān)系模型,該模型利用分水口開、關(guān)0與1狀態(tài)作為自變量,從管道末端起利用推導(dǎo)的遞推公式求出管道進(jìn)水口的等效水頭損失系數(shù),從而為以功率最小的灌溉優(yōu)化提供基礎(chǔ)。用遺傳算法對(duì)上述問題進(jìn)行了優(yōu)化求解,給出了編碼方案并建立了目標(biāo)函數(shù)。
管道水頭損失由沿程水頭損失y和局部水頭損失j組成[14],即:
式中:yj為每段的總水頭損失(m);λ為每段總水頭損失與流量關(guān)系系數(shù)(s/m2);為該段總管處的流量(m3/s)。當(dāng)放水口全關(guān)時(shí),放水口流量為0,當(dāng)放水口全開時(shí),放水口的流量與該放水口處的壓力滿足ξq,ξ為放水口流量系數(shù),此系數(shù)為閥門相對(duì)開度的函數(shù)[15],當(dāng)閥門只有全開和全關(guān)2種狀態(tài)時(shí),為將放水口在全關(guān)和全開2種狀態(tài)統(tǒng)一描述,定義放水口開關(guān)變量,全開為1,全關(guān)為0。則在的不同的狀態(tài)的流量關(guān)系統(tǒng)一表示為:
當(dāng)=1時(shí),' ξξ;當(dāng)=0時(shí),ξ=∞。而在實(shí)際計(jì)算時(shí)因∞不能參與運(yùn)算,將∞用比ξ大幾個(gè)數(shù)量級(jí)的數(shù)據(jù)表示即可。當(dāng)考慮管道水頭損失時(shí),管道中各分水口的狀態(tài)不同,各段流量也不同,導(dǎo)致總管進(jìn)水口處的壓力也不同。為研究不同輪灌分組的需要的功率,需要研究進(jìn)水口壓力與分水口狀態(tài)之間的關(guān)系。圖1為管道水頭損失計(jì)算模型,設(shè)管道的總流量為sum,管道上有個(gè)分水口,第個(gè)分水口的狀態(tài)為S,第個(gè)分水口流量為q,第段總管流量為Q,第段分水口處的壓力為H,對(duì)第個(gè)分水口,式(4)的流量系數(shù)為ξ,1。
圖1 管道水頭損失模型
對(duì)于末端第個(gè)分水口滿足Q=q,H=,則第-1個(gè)分水口處的壓力H滿足:
第-1個(gè)分水口處的壓力H1與q1滿足:
聯(lián)立式(5)和式(6),根據(jù)流量約束,可解得:
由式(9)可知,當(dāng)某分水口關(guān)閉出現(xiàn)無窮大數(shù)值時(shí),由遞推公式不會(huì)奇異值。由此遞推關(guān)系式可得到進(jìn)水口壓力與各分水口運(yùn)行狀態(tài)S的關(guān)系表達(dá)式,將S看作整數(shù)的二進(jìn)制位,由此組成的整數(shù)為s=SS…S。當(dāng)=12,λ=3.33×10-6,ξ=5.55×10-3時(shí),e,1與s的關(guān)系曲線如圖2所示。圖2中,為時(shí)間(h)。當(dāng)s=0即所有分水口都關(guān)閉時(shí),e,1=∞,在圖1中沒有顯示此數(shù)值。
在定流量灌溉時(shí),灌溉需要的功率由sum1決定,而1e,12 sum,可知e,13sum,γ為水的重度,取9 810 N/m3。因此在定流量時(shí)灌溉功率與等效水頭損失系數(shù)成正比,功率最小的目標(biāo)與等效水頭損失系數(shù)最小目標(biāo)等價(jià)。當(dāng)采用分組輪灌方式時(shí),不同的分組方式會(huì)對(duì)應(yīng)不同的等效水頭損失系數(shù),圖3為每輪灌組同時(shí)打開4個(gè)分水口的等效水頭損失系數(shù)曲線,橫坐標(biāo)為打開4個(gè)分水口對(duì)應(yīng)的分水口狀態(tài)變量s。由圖3可以看出,不同組合對(duì)應(yīng)的等效水頭損失系數(shù)相差較大,最小的水頭損失是最大水頭損失的0.772倍,存在較大的優(yōu)化空間。
圖2 ke,1與vs的關(guān)系曲線
圖3 不同輪灌組合的ke,1與vs的關(guān)系曲線
設(shè)輪灌組數(shù)為,分水口數(shù)為,當(dāng)?shù)趥€(gè)分水口在第個(gè)輪灌組中運(yùn)行,則S=1,因一個(gè)分水口只能在一個(gè)輪灌組中運(yùn)行,即S滿足約束:
這樣每個(gè)分水口有種可能,對(duì)于個(gè)分水口,可能的組合數(shù)為M。設(shè)e1為第個(gè)輪灌組的等效水頭損失系數(shù),為使總灌溉功率最小,優(yōu)化目標(biāo)函數(shù)定義為:
本文采用遺傳算法進(jìn)行優(yōu)化,遺傳算法是一種根據(jù)自然選擇和進(jìn)化機(jī)制構(gòu)造的搜索算法,通過選擇、雜交、變異等操作,群體中各個(gè)體適應(yīng)度不斷提高,直至接近最優(yōu)解,遺傳算法已廣泛用于各種復(fù)雜的組合優(yōu)化模型中。遺傳算法的運(yùn)算對(duì)象是表示個(gè)體的符號(hào)串,需要通過編碼形成的符號(hào)串稱為染色體,對(duì)于多變量?jī)?yōu)化,通常將多個(gè)變量按序排列成一條長(zhǎng)染色體,本文將每個(gè)分水口所在的輪灌組號(hào)g作為優(yōu)化變量,g滿足1≤g≤。由于每個(gè)分水口只能屬于一個(gè)輪灌組,這樣編碼滿足式(10)對(duì)應(yīng)的約束條件。但優(yōu)化運(yùn)行時(shí)為求等效水頭損失系數(shù),需要在已知S的情況下進(jìn)行,在求解適應(yīng)度函數(shù)時(shí)應(yīng)將各輪灌組號(hào)轉(zhuǎn)換為分水口運(yùn)行狀態(tài)。
式(11)的目標(biāo)為求最小值,而適應(yīng)度函數(shù)定義為求最大值,因此將求最小值問題轉(zhuǎn)換為求最大值問題,即:
式中:emax為優(yōu)化時(shí)允許的最大等效水頭損失系數(shù)。
以無錫市某水稻示范園管道灌溉為例進(jìn)行計(jì)算驗(yàn)證,該項(xiàng)目區(qū)布置有12根支管,支管長(zhǎng)度292 m,支管設(shè)計(jì)流量為sum=336 m3/h,每個(gè)支管上放水口數(shù)量為12,每個(gè)放水口設(shè)計(jì)流量為q=28 m3/h,根據(jù)設(shè)計(jì)參數(shù)計(jì)算得λ=3.33×10-6,ξ=5.55×10-3。計(jì)算時(shí)取輪灌組為3,圖4為適應(yīng)度函數(shù)值與優(yōu)化代數(shù)之間的關(guān)系曲線,進(jìn)化到135代,出現(xiàn)最優(yōu)值,最優(yōu)的適應(yīng)度函數(shù)值為0.234 89。
圖4 適應(yīng)度函數(shù)值與優(yōu)化代數(shù)之間的關(guān)系曲線
最優(yōu)值對(duì)應(yīng)的自變量分別為1、2、3、1、2、3、1、2、3、3、2、1。即第一輪灌組打開放水口序號(hào)為1、4、7、12,第二輪灌組打開放水口序號(hào)為2、5、8、11,第三輪灌組打開放水口序號(hào)為3、6、9、10。
輪灌分組的優(yōu)化算法較多,比較常見的優(yōu)化如遺傳算法粒子群算法等,高偉增等[7-8]利用遺傳算法和對(duì)遺傳算法的編碼的改進(jìn)來提高渠道輪灌優(yōu)化進(jìn)度精度和收斂速度,本文在優(yōu)化求解方法與上述做法相似;如果考慮在一段輪灌時(shí)段內(nèi)的輪灌分組優(yōu)化,則應(yīng)考慮一次性引水約束,文獻(xiàn)[11]提出了改進(jìn)的規(guī)劃模型,實(shí)現(xiàn)了在輪灌周期內(nèi)的渠道輪灌優(yōu)化。上述渠道優(yōu)化一般不考慮水頭損失,主要考慮流量的最優(yōu)分配,如果考慮水頭損失,通常做法是選擇幾種典型的分組方案,分別計(jì)算幾種典型方案的水頭損失,然后選擇最小水頭損失的方案作為運(yùn)行方案,這種方法比較適合于分組方案較少且分水口布置比較均勻的場(chǎng)合。程毅強(qiáng)[5]選擇集中式和半集中式2種輪灌方式,計(jì)算這2種方式需要的揚(yáng)程,表明半集中式需要的揚(yáng)程小,水頭損失也小,該結(jié)論與本文的研究結(jié)果吻合。但這種方法并沒有實(shí)現(xiàn)全局的最優(yōu)化,在大規(guī)模復(fù)雜場(chǎng)合運(yùn)行效果差。
本文提出的遞推模型將分水口打開和關(guān)閉的水頭損失統(tǒng)一考慮,利用計(jì)算機(jī)可以快速計(jì)算所有輪灌組合下的水頭損失,從而為全局優(yōu)化提供了基礎(chǔ)。在分水口全開、全關(guān)模式下實(shí)現(xiàn)優(yōu)化時(shí),當(dāng)分水口全關(guān)時(shí),水頭損失系數(shù)為無窮大,為求所有分水口的不同組合對(duì)供水壓力的要求,需建立不同分水口狀態(tài)與壓力的關(guān)系,給出的各分水口壓力的遞推公式將無窮大和有界參數(shù)參與運(yùn)算,不會(huì)產(chǎn)生奇異值。本文的優(yōu)化計(jì)算雖然以等間隔分水口為例進(jìn)行的,但該模型仍然適用于分水口非等間隔布置,或者支管管徑不同的場(chǎng)合,在這種情況下只需要分別計(jì)算各段支管的水頭損失系數(shù)即可,優(yōu)化實(shí)現(xiàn)時(shí)不需要改動(dòng)其他代碼。
1)以智能一體化閘門或閥門為基礎(chǔ)的精細(xì)調(diào)度可以提供更精確的流量分配,以定流量方式灌溉時(shí)所需的功率最小的目標(biāo)與進(jìn)口側(cè)等效水頭損失系數(shù)最小的目標(biāo)等價(jià),在分組輪灌時(shí)目標(biāo)函數(shù)為所有分組的等效水頭損失系數(shù)的和為最小。
2)在分水口等間隔布置時(shí),輪灌分組按輪灌分組數(shù)等間隔安排所需功率為最小,優(yōu)化后的水頭損失系數(shù)可以減小到?jīng)]有優(yōu)化前的0.772倍。因此,分配輪灌分組時(shí),每組的分水口應(yīng)等間隔布置,輪灌組之間的分配差異應(yīng)盡量小。
[1] 馬守臣, 張偉強(qiáng), 段愛旺. 不同虧缺灌溉方式對(duì)冬小麥產(chǎn)量及水分利用效率的影響[J]. 灌溉排水學(xué)報(bào), 2019, 38(8): 9-14.
MA Shouchen, ZHANG Weiqiang, DUAN Aiwang. Effects of different deficit irrigation modes on grain yield and water use efficiency of winter wheat[J]. Journal of Irrigation and Drainage, 2019, 38(8): 9-14.
[2] 龐喆, 王啟龍. 不同灌溉量對(duì)土壤理化性質(zhì)及水稻生長(zhǎng)發(fā)育的影響[J]. 灌溉排水學(xué)報(bào), 2019, 38(S2): 37-41.
PANG Zhe, WANG Qilong. Effects of different irrigation amount on reconstructing soil physical and chemical properties and rice growth[J]. Journal of Irrigation and Drainage, 2019, 38(S2): 37-41.
[3] 包志炎, 王學(xué)斌, 張海波, 等. 基于物聯(lián)網(wǎng)和云架構(gòu)的渠灌閘門智能控制系統(tǒng)[J]. 農(nóng)業(yè)機(jī)械學(xué)報(bào), 2017, 48(11): 222-228.
BAO Zhiyan, WANG Xuebin, ZHANG Haibo, et al. Intelligent control system of canal irrigation sluice based on Internet of Things and cloud architecture[J]. Transactions of the Chinese Society for Agricultural Machinery, 2017, 48(11): 222-228.
[4] 郭相平, 王敏, 陳盛, 等. 江蘇省稻作區(qū)低壓管道灌溉適宜控制規(guī)模研究[J]. 灌溉排水學(xué)報(bào), 2019, 38(11): 28-35.
GUO Xiangping, WANG Min, CHEN Sheng, et al. Study on suitable control scale of low pressure pipeline irrigation in rice growing area of Jiangsu Province[J]. Journal of Irrigation and Drainage, 2019, 38(11): 28-35.
[5] 程毅強(qiáng). 關(guān)于優(yōu)化滴灌輪灌運(yùn)行方式的探討[J]. 中國(guó)水運(yùn)(下半月), 2013, 13(9): 232-233.
CHENG Yiqiang. Discussion on optimization for the operation mode of drip irrigation [J]. China Water Transport, 2013, 13(9): 232-233.
[6] 張宇. 基于輪灌方案的鄂爾多斯黃河南岸灌區(qū)水資源優(yōu)化調(diào)配[D]. 鄭州: 華北水利水電大學(xué), 2016.
ZHANG Yu. Optimal allocation of water resources based on the rotational irrigation scheme at the southern bank of Ordos Yellow River irrigation area[D]. Zhengzhou: North China University of Water Resources and Electric Power, 2016.
[7] 高偉增, 趙明富, 汪志農(nóng), 等. 渠道輪灌配水優(yōu)化模型與復(fù)合智能算法求解[J]. 干旱地區(qū)農(nóng)業(yè)研究, 2011, 29(6): 38-42.
GAO Weizeng, ZHAO Mingfu, WANG Zhinong, et al. Optimization model of canal water distribution with GA and FS in rotation irrigation[J]. Agricultural Research in the Arid Areas, 2011, 29(6): 38-42.
[8] GAO Weizeng, YU Zhou. Optimization Model of Rotation Irrigation Channel Distribution with GA and FS[J]. AICI, 2011, 237: 1-8.
[9] ANWAR A A, HAQ Z U. Arranged-demand irrigation scheduling with nonidentical discharges[J]. Journal of Irrigation and Drainage Engineering, 2016, 142(9): 04016033.
[10] DE VRIES T T, ANWAR A A. Irrigation scheduling using complex machine scheduling[J]. Journal of Irrigation and Drainage Engineering, 2015, 141(5): 04014065.
[11] KAUR S, SRIVASTAVA D K, ARYA D S. Improved planning model for canal scheduling of rotational irrigation[J]. Journal of Irrigation and Drainage Engineering, 2013, 139(7): 560-570.
[12] 張志宇, 郄志紅, 吳鑫淼. 冬小麥-夏玉米輪作體系灌溉制度多目標(biāo)優(yōu)化模型[J]. 農(nóng)業(yè)工程學(xué)報(bào), 2013, 29(16): 102-111.
ZHANG Zhiyu, QIE Zhihong, WU Xinmiao. Multi-objective optimization model of irrigation schedule for winter wheat-summer maize rotation system[J]. Transactions of the Chinese Society of Agricultural Engineering, 2013, 29(16): 102-111.
[13] 于芷婧, 尚松浩. 華北輪作農(nóng)田灌溉制度多目標(biāo)優(yōu)化模型及應(yīng)用[J].水利學(xué)報(bào), 2016, 47(9): 1 188-1 196.
YU Zhijing, SHANG Songhao. Multi-objective optimization method for irrigation scheduling of crop rotation system and its application in North China[J]. Journal of Hydraulic Engineering, 2016, 47(9): 1 188-1 196.
[14] 曲世琳, 伍悅濱, 趙洪賓. 閥門在給水管網(wǎng)系統(tǒng)中流量調(diào)節(jié)特性的研究[J]. 流體機(jī)械, 2003, 31(11): 16-18, 32.
QU Shilin, WU Yuebin, ZHAO Hongbin. Study on flow adjustment characteristic of valves in water distribution system[J]. Fluid Machinery, 2003, 31(11): 16-18, 32.
[15] 陳松. 閥門流量特性分析與優(yōu)化[J]. 機(jī)電信息, 2018(6): 88-89.
CHEN Song. Analysis and optimization of valve flow characteristics[J]. Mechanical and Electrical Information, 2018(6): 88-89.
Optimizing the Outlet Distribution of Pipeline Irrigation for Rotation Irrigation with Hydraulic Loss in Consideration
LI Bin1, LI Na2, LI Duanming2, GONG Shiwen2
(1.The College of Electrical, Energy and Power Engineering, Yangzhou University, Yangzhou 225127, China;2. China Irrigation and Drainage Development Center, Beijing 100054, China)
【】Low-pressure pipeline using pipes in lieu of open channels to convey water is a water-saving irrigation technology as it reduces leakage and evaporation. Low-pressure pipeline irrigation has been well documented and rolled-up in China, from dry farmlands in the north to paddy fields in the south, from well-irrigated areas to surface-water irrigated regions, from plain areas to hilly terrains. With the development in automation and the reduced cost of control systems, control of the outlets of the irrigation system has become more automatic. Modeling hydraulic dynamics at the outlets so as to optimize the outlet is hence required.【】We present a method in this paper to optimize outlet distribution of the low-pressure pipeline system for rotation irrigation with hydraulic head loss in the system being taken into account, aimed to meet the demand for water flow rate while in the meantime reduce the costs of electricity usage.【】The optimization is to determine the hydraulic loss under different outlets so as to find their relationship with the inlet pressure in the pipeline network; it also considered hydraulic head loss in the system. The equivalent hydraulic loss coefficient of the pipeline inlet was calculated using a binary variable as independent variable, and calculation of the equivalent hydraulic loss coefficient of the pipeline inlet started from the end of the pipeline using the deduced - recurrence formula. The objective of the optimization is to minimize the energy used by the rotation irrigation, with water flow rate fixed. The genetic algorithm and the coding scheme were used to solve the optimization, in which the irrigation group numbers at each water outlet were taken as the optimization variables, with a constraint that each outlet can only run one irrigation group.【】The energy required for the equal interval arrangement in the rotation irrigation was minimized, and the optimized results show that the optimized hydraulic loss coefficient could be reduced by 0.772 times compared to that obtained without optimization.【】The recursive formula for calculating the hydraulic loss at each outlet can take infinite or bounded parameters without producing singular values. The model can be combined with constant flow optimization; it is also suitable for non-equal spaced branch pipes with different diameters, with the head loss coefficient for each branch pipe calculated separately.
rotation irrigation; hydraulic loss; model; genetic algorithm
S274
A
10.13522/j.cnki.ggps.2020168
1672 - 3317(2021)01 - 0144 - 05
2019-03-23
國(guó)家重點(diǎn)研發(fā)計(jì)劃項(xiàng)目(2018YFC1508304)
李彬(1966-),男,江蘇鹽城人。副教授,主要從事水利工程自動(dòng)化與信息化方向研究。E-mail: 13813199350@163.com
李彬, 李娜, 李端明, 等. 考慮水頭損失的管道灌溉分水口輪灌分組優(yōu)化模型[J]. 灌溉排水學(xué)報(bào), 2021, 40(1): 144-148.
LI Bin, LI Na, LI Duanming, et al.Optimizing the Outlet Distribution of Pipeline Irrigation for Rotation Irrigation with Hydraulic Loss in Consideration [J]. Journal of Irrigation and Drainage, 2021, 40(1): 144-148.
責(zé)任編輯:陸紅飛