Potato planter performance and effects of non-uniform spacing

1986 ◽  
Vol 63 (1) ◽  
pp. 25-37 ◽  
Author(s):  
J. B. Sieczka ◽  
E. E. Ewing ◽  
E. D. Markwardt
2014 ◽  
Vol 31 (2) ◽  
pp. 439-454
Author(s):  
A. S. El sayed ◽  
M. A. A. Mady ◽  
S. M. El – Amir ◽  
I.T. Abu-Eash

2018 ◽  
Vol 34 (5) ◽  
pp. 819-830 ◽  
Author(s):  
Aurelie M. Poncet ◽  
John P. Fulton ◽  
Timothy P. McDonald ◽  
Thorsten Knappenberger ◽  
Joey N. Shaw ◽  
...  

Abstract. Optimization of planter performance such as uniform seeding depth is required to maximize crop yield potential. Typically, seeding depth is manually adjusted prior to planting by selecting a row-unit depth and a row-unit downforce to ensure proper seed-soil contact. Once set, row-unit depth and downforce are usually not adjusted again for a field although soil conditions may vary. Optimization of planter performance requires automated adjustments of planter settings to varying soil conditions, but development of precision technologies with such capabilities requires a better understanding of soil-planter interactions. The objective of this study was to evaluate seeding depth response to varying soil conditions between and within fields and to discuss implications for development and implementation of active planting technologies. A 6-row John Deere MaxEmerge Plus planter equipped with heavy-duty downforce springs was used to plant corn ( L.) in central Alabama during the 2014 and 2015 growing seasons. Three depths (4.4, 7.0, and 9.5 cm) and three downforces (corresponding to an additional row-unit weight of 0.0, 1.1, and 1.8 kN) were selected to represent common practices. Depth and downforce were not readjusted between fields and growing seasons. Seeding depth was measured after emergence. Corn seeding depth significantly varied with heterogeneous soil conditions between and within fields and the planter failed to achieve uniform seeding depth across a field. Differences in corn seeding depth between fields and growing seasons were as high as 2.1 cm for a given depth and downforce combination. Corn seeding depth significantly co-varied with field elevation but not with volumetric soil water content. Seeding depth varied with elevation at a rate ranging from -0.1 cm/m to -0.6 cm/m. Seeding depth co-variation to field elevation account for some but not all site-specific seeding depth variability identified within each field trial. These findings provide a better understanding of site-specific seeding depth variability and issues to address for the development of site-specific planting technologies to control seeding depth accuracy and improve uniformity. Keywords: Depth control, Downforce, Planter, Precision agriculture, Seeding depth, Uniformity.


Author(s):  
Sriram Shankaran ◽  
Brian Barr

The objective of this study is to develop and assess a gradient-based algorithm that efficiently traverses the Pareto front for multi-objective problems. We use high-fidelity, computationally intensive simulation tools (for eg: Computational Fluid Dynamics (CFD) and Finite Element (FE) structural analysis) for function and gradient evaluations. The use of evolutionary algorithms with these high-fidelity simulation tools results in prohibitive computational costs. Hence, in this study we use an alternate gradient-based approach. We first outline an algorithm that can be proven to recover Pareto fronts. The performance of this algorithm is then tested on three academic problems: a convex front with uniform spacing of Pareto points, a convex front with non-uniform spacing and a concave front. The algorithm is shown to be able to retrieve the Pareto front in all three cases hence overcoming a common deficiency in gradient-based methods that use the idea of scalarization. Then the algorithm is applied to a practical problem in concurrent design for aerodynamic and structural performance of an axial turbine blade. For this problem, with 5 design variables, and for 10 points to approximate the front, the computational cost of the gradient-based method was roughly the same as that of a method that builds the front from a sampling approach. However, as the sampling approach involves building a surrogate model to identify the Pareto front, there is the possibility that validation of this predicted front with CFD and FE analysis results in a different location of the “Pareto” points. This can be avoided with the gradient-based method. Additionally, as the number of design variables increases and/or the number of required points on the Pareto front is reduced, the computational cost favors the gradient-based approach.


2020 ◽  
Vol 17 ◽  
pp. 00150
Author(s):  
Nikolai P. Laryushin ◽  
Oleg N. Kukharev ◽  
Anton S. Bochkarev ◽  
Vladimir S. Bochkarev

The paper considers the design and operation of the experimental mini potato planter for small-scale farms (private subsidiary farms – PSF). It presents the results of field studies of experimental potato planter in field conditions. The paper also describes probabilistic curves of potato tubers distribution in a furrow depending on motion speed and design parameters of tubers speed damper.


1970 ◽  
Vol 48 (2) ◽  
pp. 235-240 ◽  
Author(s):  
Kees Vermeer

Canada goose clutches situated on islands in Dowling Lake and Lake Newell, Alberta, were checked from laying to hatching. Egg-laying intervals averaged 1.87 days and incubation periods 26.8 days. The distribution of nests showed a significant deviation from randomness in the direction of uniform spacing. Causes of extensive hatching failure at Dowling Lake were predation and desertion. Predation by coyotes was facilitated by low water levels. A preference for nesting on islands appears to be a mechanism to counteract mammalian predation.


2018 ◽  
Vol 66 (9) ◽  
pp. 4687-4694 ◽  
Author(s):  
Qinghua Song ◽  
Zhongxiang Shen ◽  
Jian Lu
Keyword(s):  

2012 ◽  
Vol 42 (3) ◽  
pp. 7
Author(s):  
Ismail Z. Ebrahem ◽  
Amer Eissa Ayman ◽  
Riccardo Guidetti
Keyword(s):  

1999 ◽  
Vol 75 (6) ◽  
pp. 967-972 ◽  
Author(s):  
John C. Brissette ◽  
Robert M. Frank Jr. ◽  
Timothy L. Stone ◽  
Thomas A. Skratt

Four levels of precommercial thinning were applied with and without fertilization in a young, even-aged stand of northern conifers in east-central Maine. After 18 years, precommercial thinning resulted in longer and wider crowns and greater survival, growth, and yield of selected crop trees compared to untreated controls. Growth and yield were greater with uniform spacing at approximately 2.4 × 2.4 m and 1.5-m row thinning with crop-tree release in residual strips than with row thinning without crop-tree release. Control of stand species composition was greatest with uniform spacing. Fertilization had no significant effect.


Sign in / Sign up

Export Citation Format

Share Document