@article { author = {باقری, نیکروز and احمدی, حجت and علوی پناه, سیدکاظم and امید, محمود and گرامی, کریم}, title = {A Map-Based System for Variable Rate Liquid Nitrogen Fertilizer Application}, journal = {Food Engineering Research}, volume = {13}, number = {4}, pages = {97-108}, year = {2013}, publisher = {Agricultural Engineering Research Institute}, issn = {2645-4513}, eissn = {2645-4521}, doi = {10.22092/jaer.2013.100292}, abstract = {This research designed, constructed and evaluated a map-based variable rate application system for liquid nitrogen fertilizer. Solenoid valves were used to change nozzle flow using pulse-wide modulation technology. A turbine flow sensor and GPS module were used to measure solenoid valve flow and online system coordination, respectively. The graphical user interface software was designed by Visual Basic 6. This program received online coordination from a GPS module, received fertilizer map data, compared online and map coordinates, specified application order, received sensor output and compared it with optimum data and then applied proportional closed-loop control. To evaluate the system, accuracy and time-delay experiments were carried out with 3 replications. The results showed that the average difference between map data and system flow for open and close-loop controllers were 10.0 and 3.6%, respectively. The maximum time delay was 0.54 s. Results also showed that, at 1% probability, no significant difference was observed between the system flow and nitrogen fertilizer map data.This research designed, constructed and evaluated a map-based variable rate application system for liquid nitrogen fertilizer. Solenoid valves were used to change nozzle flow using pulse-wide modulation technology. A turbine flow sensor and GPS module were used to measure solenoid valve flow and online system coordination, respectively. The graphical user interface software was designed by Visual Basic 6. This program received online coordination from a GPS module, received fertilizer map data, compared online and map coordinates, specified application order, received sensor output and compared it with optimum data and then applied proportional closed-loop control. To evaluate the system, accuracy and time-delay experiments were carried out with 3 replications. The results showed that the average difference between map data and system flow for open and close-loop controllers were 10.0 and 3.6%, respectively. The maximum time delay was 0.54 s. Results also showed that, at 1% probability, no significant difference was observed between the system flow and nitrogen fertilizer map data.}, keywords = {Fertilizer applicator,Nitrogen fertilizer,Precision agriculture,Variable rate technology}, title_fa = {طراحی و ساخت سامانه پاشش نرخ متغیر کود نیتروژن مایع نقشه- مبنا}, abstract_fa = {هدف از این پژوهش طراحی و ساخت سامانه پاشش نرخ متغیر کود نیتروژن مایع برای برگ­پاشی ذرت است.  از شیرهای سلونوئیدی جهت تغییر بده خروجی افشانک­ها با استفاده از فناوری تعدیل عرض پالس (PWM) و از حسگرهای بده توربینی و ماژول GPS به ترتیب برای اندازه­گیری بده شیرهای سلونوئیدی و تعیین مختصات لحظه­ای دستگاه استفاده شد.  نرم­افزار سامانه با استفاده از زبان برنامه­نویسی ویژوال بیسیک 6 نوشته شد.  وظایف نرم­افزار عبارت است از: دریافت مختصات لحظه­ای GPS، دریافت اطلاعات نقشه کود نیتروژن، مقایسه مختصات لحظه‌ای دستگاه با مختصات نقشه کود، صدور دستور پاشش به شیرهای سلونوئیدی، دریافت خروجی حسگرها و مقایسه با بده مطلوب و سرانجام اعمال سامانه کنترل.  به منظور بررسی عملکرد سامانه، آزمون­های دقت و تأخیر زمانی پاشش در سه تکرار اجرا شد.  نتایج نشان می‌دهد میانگین اختلاف مقادیر بده نقشه کود با بده خروجی سامانه در وضعیت کنترل حلقه باز و حلقه بسته آزمون­ها به ترتیب 0/10 و 6/3 درصد و حداکثر مقدار تأخیر زمانی سامانه 54/0 ثانیه است.  نتایج آزمون t- جفت شده نشان می‌دهد که بین مقادیر بده خروجی سامانه و بده نقشه کود در سطح احتمال یک درصد تفاوت معنی­داری وجود ندارد.  }, keywords_fa = {}, url = {https://fooder.areeo.ac.ir/article_100292.html}, eprint = {https://fooder.areeo.ac.ir/article_100292_8ae135b0fb2d746b83ad6f6e89b51a84.pdf} }