Effect of the Sowing Speed on the Distribution Regularity of Maize Seeds

2019 ◽  
pp. 1-8 ◽  
Author(s):  
Wesley Nadin ◽  
Pedro Silvério Xavier Pereira ◽  
Onassis Henrique Simon Rondon ◽  
Matheus Farinha Afonso ◽  
Dryelle Sifuentes Pallaoro ◽  
...  
Keyword(s):  
Coefficient Of Variation ◽  
Longitudinal Distribution ◽  
Initial Population ◽  
Precision Index ◽  
Maize Seeds ◽  
Plant Stand ◽  
The Mean ◽  
Seed Deposition ◽  
Displacement Speed ◽  
Deposition Depth

This work aimed to evaluate the influence of the sowing speed on the regularity of longitudinal distribution of maize seeds through a pneumatic metering seeder. The experimentation of 4 sowing speeds (4, 6, 8 and 10 km h-1) was performed in randomized blocks design with four replicates. The parameters evaluated were the mean distance between plants, coefficient of variation of the distance between plants, percentage of acceptable, flawed and double spacings, precision index, plant stand, initial population, mean seed deposition depth, and coefficient of variation of the seed deposition depth. The increase in the operating speed linearly reduced the percentage of acceptable spacings, plant stand, initial population, and mean seed deposition depth. Conversely, it linearly increased the values of mean distance between plants, coefficient of variation of the distance between plants, percentage of double and flawed spacings, precision index, and coefficient of variation of the deposition depth. Therefore, the increase in the displacement speed of the tractor-seeder set reduced the regularity of the longitudinal distribution of the plants, as well as the sowing quality.

Design and development of manually operated gladiolus planter

2018 ◽  
Vol 5 (01) ◽  
Author(s):  
TAPAN K. KHURA ◽  
H. L. KUSHWAHA ◽  
SATISH D LANDE ◽  
PKSAHOO . ◽  
INDRA L . KUSHWAHA
Keyword(s):  
Coefficient Of Variation ◽  
Field Capacity ◽  
Power Source ◽  
Forward Speed ◽  
Cereal Crop ◽  
Maximum Coefficient ◽  
Coefficient Of Uniformity ◽  
The Mean ◽  
The Cost ◽  
Immense Potential

Floriculture is an age-old farming activity in India having immense potential for generating selfemployment and income to farmers. However, the cost of cultivation of flower is high as compared to cereal crop. Level of mechanization for different field operations is one but foremost reason for the higher cost of cultivation. As most of the Indian farmers are marginal and small, a need for manually operated gladiolus planter was felt. The geometric properties of gladiolus corm were determined for designing the seed metering system and seed hopper of the planter. The planter was evaluated in the field when pulled by two persons as a power source and guided by a person. The coefficient of variation and highest deviation from the mean spacing was observed as 12.93% and 2.65cm respectively. The maximum coefficient of uniformity of 90.59% was observed for a nominal corm spacing of 15cm at 0.56 kmh-1 forward speed. An average MISS percentage was observed as 2.65 and 2.25 for nominal corm spacing of 15 and 20 cm. The multiple index was zero for two levels corm spacing and forward speed of operation. The QFI was found in the range of 97.2 and 97.9 percent. The average field capacity of the planter was observed as 0.02 hah-1.The average draft requirement of the planter was found as 821 ± 50.3 N.

scholarly journals Technical note: Inherent benchmark or not? Comparing Nash–Sutcliffe and Kling–Gupta efficiency scores

2019 ◽  
Vol 23 (10) ◽  
pp. 4323-4331 ◽  
Author(s):  
Wouter J. M. Knoben ◽  
Jim E. Freer ◽  
Ross A. Woods
Keyword(s):  
Time Series ◽  
Coefficient Of Variation ◽  
Ad Hoc ◽  
Model Performance ◽  
Technical Note ◽  
Mean Flow ◽  
Model Adequacy ◽  
Robust Model ◽  
The Mean ◽  
Adequacy Assessment

Abstract. A traditional metric used in hydrology to summarize model performance is the Nash–Sutcliffe efficiency (NSE). Increasingly an alternative metric, the Kling–Gupta efficiency (KGE), is used instead. When NSE is used, NSE = 0 corresponds to using the mean flow as a benchmark predictor. The same reasoning is applied in various studies that use KGE as a metric: negative KGE values are viewed as bad model performance, and only positive values are seen as good model performance. Here we show that using the mean flow as a predictor does not result in KGE = 0, but instead KGE =1-√2≈-0.41. Thus, KGE values greater than −0.41 indicate that a model improves upon the mean flow benchmark – even if the model's KGE value is negative. NSE and KGE values cannot be directly compared, because their relationship is non-unique and depends in part on the coefficient of variation of the observed time series. Therefore, modellers who use the KGE metric should not let their understanding of NSE values guide them in interpreting KGE values and instead develop new understanding based on the constitutive parts of the KGE metric and the explicit use of benchmark values to compare KGE scores against. More generally, a strong case can be made for moving away from ad hoc use of aggregated efficiency metrics and towards a framework based on purpose-dependent evaluation metrics and benchmarks that allows for more robust model adequacy assessment.

Effects of the Fractional Laplacian Order on the Nonlocal Elastic Rod Response

2017 ◽  
Vol 3 (3) ◽  
Author(s):  
Giuseppina Autuori ◽  
Federico Cluni ◽  
Vittorio Gusella ◽  
Patrizia Pucci
Keyword(s):  
Probability Density Function ◽  
Probability Density ◽  
Density Function ◽  
Coefficient Of Variation ◽  
Fractional Laplacian ◽  
Numerical Procedure ◽  
Elastic Rod ◽  
The Mean ◽  
Distributed Forces ◽  
Nonlinear Fashion

In this paper, we yield with a nonlocal elastic rod problem, widely studied in the last decades. The main purpose of the paper is to investigate the effects of the statistic variability of the fractional operator order s on the displacements u of the rod. The rod is supposed to be subjected to external distributed forces, and the displacement field u is obtained by means of numerical procedure. The attention is particularly focused on the parameter s, which influences the response in a nonlinear fashion. The effects of the uncertainty of s on the response at different locations of the rod are investigated by the Monte Carlo simulations. The results obtained highlight the importance of s in the probabilistic feature of the response. In particular, it is found that for a small coefficient of variation of s, the probability density function of the response has a unique well-identifiable mode. On the other hand, for a high coefficient of variation of s, the probability density function of the response decreases monotonically. Finally, the coefficient of variation and, to a small extent, the mean of the response tend to increase as the coefficient of variation of s increases.

Calibration of Experiments on Perennial Crops using Covariance Analysis: the Case of Coconut

1986 ◽  
Vol 22 (4) ◽  
pp. 353-361
Author(s):  
Tilak Abeysinghe
Keyword(s):  
Coefficient Of Variation ◽  
Experimental Error ◽  
Covariance Analysis ◽  
Mean Square ◽  
Perennial Crops ◽  
Randomized Design ◽  
Calibration Experiment ◽  
Experimental Yield ◽  
The Mean

SUMMARYThe calibrating efficiency of the pre-experimental yield of coconuts was examined using ten years data from a calibration experiment. On the basis of a fully randomized design it was found that the two-year pooled pre-experimental yield on four-tree plots produces consistent calibration and reduces the experimental error mean square by about 73%. This brings down the mean coefficient of variation to 9.7% from its pre-calibration levels of 36 on one-tree plots and 18 on four-tree plots.

Estimating the intra- and inter-individual imprecision of manual pipetting

2017 ◽  
Vol 55 (7) ◽  
Author(s):  
Giuseppe Lippi ◽  
Gabriel Lima-Oliveira ◽  
Giorgio Brocco ◽  
Antonella Bassi ◽  
Gian Luca Salvagno
Keyword(s):  
Coefficient Of Variation ◽  
Biological Samples ◽  
Inverse Correlation ◽  
Distilled Water ◽  
Years Of Experience ◽  
Laboratory Practice ◽  
Scientific Publications ◽  
Plastic Container ◽  
Water Solutions ◽  
The Mean

AbstractBackground:Despite the importance of manual pipetting of fluids such as water, solutions, buffers, reagents, or biological samples in daily laboratory practice, the intra- and inter-individual imprecision of this activity has not been recently described in scientific publications.Methods:Twenty laboratory operators were randomly enrolled for this study. Imprecision of manual pipetting was estimated by asking each laboratory professional to dispense 1 mL, 100 μL or 10 μL of distilled water for 10 consecutive times with three certified pipettes into a 50-mL plastic container placed into a gravimetric balance. The weight of the water dispensed was systematically recorded for each of the 10 repeated attempts, and the inter- and intra-operator imprecision was finally calculated and expressed as coefficient of variation (CV%).Results:The mean intra-individual imprecision was 5.7% (range, 0%–11.8%) for pipetting 10 μL, 0.8% (range, 0.4%–1.9%) for pipetting 100 μL, and 0.2% (range, 0.1%–0.5%) for pipetting 1 mL. Overall, the mean inter-individual imprecision was 8.1% for pipetting 10 μL, 1.1% for pipetting 100 μL and 0.4% for pipetting 1 mL. A significantly inverse correlation was found between intra-individual pipetting imprecision and the amount of water dispensed (r = –0.80; p<0.001). No significant correlation was observed between individual pipetting performance and sex, age, qualification, and years of experience in the laboratory.Conclusions:The results of this study show that manual pipetting is plagued by a considerable intra- and inter-individual imprecision, which is inversely correlated with the amount of fluid dispensed.

scholarly journals Effect of Seeding Rate On Growth And Yield Of Okra (Abelmoschus Esculantus) In Zuru Northern Guinea Savanna Of Nigeria

2018 ◽  
Vol 6 (02) ◽  
Author(s):  
Yohanna J, A. ◽  
Muhammad A, M.
Keyword(s):  
Block Design ◽  
Total Yield ◽  
Growth And Yield ◽  
Land Resource ◽  
Seeding Rate ◽  
Randomized Complete Block Design ◽  
Number Of Leaves ◽  
Resource Space ◽  
Plant Stand ◽  
The Mean

Field experiment was carried out during 2010 rainy season to find the effect of seeding rate on the growth and yield of okra (Abelmuschus esculentus) in Zuru Northern Guinea Savannah. Zuru is located in Zuru Local government area of Kebbi State (Latitude 11o 251 to 11o 551 North and Longitude 4o 51 to 5o 251 East of the equator). The experiment consisted of three treatments that is planting okra at one plant per stand (S1), two plants per stand (S2) and three plants per stand (S3). The experiment was laid out in randomized complete block design (RCBD) and the treatments replicated three time. The result of the experiment has shown that plant height and number of leaves/plant at 3, 6 and 9 weeks after planting (    WAP) were significantly influenced by seeding rate (P<0.05). At 3, 6 and 9 WAP tallest plants were obtained from okra plants planted at three plants/stand (27.83, 54.0 and 77.0cm) respectively followed by okra planted at two plant/stand (24.77, 50.67 and 74.33 leave/plant respectively ). However, more number of leaves/plant were obtained from okra plant at one plant/stand (9.67, 24.67 and 48.0 leaves/plant respectively) followed by okra planted at two plants/stand (8.33, 18.33 and 36.33 leaves/plant respectively). Seeding rate had significant influence on time of 50 percent flowering with one plant/stand first attaining 50 percent flowering stage just within 36.33 days followed by okra planted at two plants/stand (38 days). The mean fresh fruit yield of okra was also significantly influenced by seeding rate with the highest yield of fresh fruits obtained from three plants/stand (83.34/ha) followed by okra planted at two plants/stand (55.56/ha). However, the result of the findings recommends that, okra should be planted at two plants/stand for medium sized and marketable okra fresh fruits since at three plants/stand leads to the production of undersized fresh fruits which do not often attract customers. At one plant/stand, there seemed to be early fruiting and bigger sized fresh fruits but low total yield due to underutilization of land resource/space. Planting at one plant/stand should therefore be avoided

scholarly journals Probabilistic Bearing Capacity of a Pavement Resting on Fibre Reinforced Embankment Considering Soil Spatial Variability

2021 ◽  
Vol 7 ◽  
Author(s):  
Kouseya Choudhuri ◽  
Debarghya Chakraborty
Keyword(s):  
Spatial Variability ◽  
Soil Properties ◽  
Bearing Capacity ◽  
Coefficient Of Variation ◽  
Friction Angle ◽  
Horizontal Scale ◽  
Vertical Scale ◽  
Scale Of Fluctuation ◽  
The Mean ◽  
The Finite Difference Method

This paper intends to examine the influence of spatial variability of soil properties on the probabilistic bearing capacity of a pavement located on the crest of a fibre reinforced embankment. An anisotropic random field, in combination with the finite difference method, is used to carry out the probabilistic analyses. The cohesion and internal friction angle of the soil are assumed to be lognormally distributed. The Monte Carlo simulations are carried out to obtain the mean and coefficient of variation of the pavement bearing capacity. The mean bearing capacity of the pavement is found to decrease with the increase in horizontal scale of fluctuation for a constant vertical scale of fluctuation; whereas, the coefficient of variation of the bearing capacity increases with the increase in horizontal scale of fluctuation. However, both the mean and coefficient of variation of bearing capacity of the pavement are observed to be increasing with the increase in vertical scale of fluctuation for a constant horizontal scale of fluctuation. Apart from the different scales of fluctuation, the effects of out of the plane length of the embankment and randomness in soil properties on the probabilistic bearing capacity are also investigated in the present study.

scholarly journals Use of Frenum in Determining the Original Vertical Position of Teeth

2013 ◽  
Vol 7 (1) ◽  
pp. 44-46 ◽  
Author(s):  
KD Prasad ◽  
H Alva
Keyword(s):  
Coefficient Of Variation ◽  
Vertical Position ◽  
Central Incisor ◽  
Incisal Edge ◽  
The Mean ◽  
Natural Dentition ◽  
Lingual Frenum ◽  
Functional Position

ABSTRACT Purpose To determine the functional position of labial, lingual and buccal frenii with the corresponding central incisor, premolar or molars in natural dentition. Materials and method 20 dentate subjects between 20-40years of age were selected for the study. Maxillary and mandibular impressions were made and the distance from anterior attachment of frenum to the cusp tip of the corresponding tooth was measured. Result The mean distance between the anterior attachment of labial frenum to the incisal edge of incisor was 12.25mm, the mean distance between the anterior attachment of buccal frenum of right side to cusp tip of corresponding teeth was 12.75mm and left side was 12.8mm and the mean distance between the anterior attachment of lingual frenum to incisal edge of incisor was 15.4mm. The coefficient of variation were 14.7%, 16.65%, 15.75% and 6.4% respectively. Conclusion The distance between the anterior attachment of the frenum to the cusp tips/incisal edges can be used as a pre-extraction record for determining the original vertical position of teeth.

Glycohaemoglobin: Comparison of 12 Analytical Methods, Applied to Lyophilized Haemolysates by 101 Laboratories in an External Quality Assurance Programme

1993 ◽  
Vol 30 (2) ◽  
pp. 169-174 ◽  
Author(s):  
Cas W Weykamp ◽  
Theo J Penders ◽  
Frits A J Muskiet ◽  
Willem van der Slik
Keyword(s):  
Quality Assurance ◽  
Acetic Acid ◽  
Coefficient Of Variation ◽  
External Quality Assurance ◽  
External Quality ◽  
Quality Assurance Programme ◽  
Coefficients Of Variation ◽  
Two Samples ◽  
The Mean ◽  
Edta Blood

Stable lyophilized ethylenediaminetetra-acetic acid (EDTA)-blood haemolysates were applied in an external quality assurance programme (SKZL, The Netherlands) for glycohaemoglobin assays in 101 laboratories using 12 methods. The mean intralaboratory day-to-day coefficient of variation (CV), calculated from the assay of 12 unidentified pairs over a period of 1 year, was 5·2% (range: 0·2–28·7). Forty-seven per cent of laboratories did not meet the criterion of CV < 5%, whereas 68% did not meet the clinically more desirable 3·3–3·6%. Linearity, as derived from the analysis of five combinations of two haemolysates with low and high glycohaemoglobin percentages over 6 months, was excellent (mean correlation coefficient 0·9953; range: 0·9188–0·9999). Analysis of two samples with high and low glycohaemoglobin percentages gave mean interlaboratory coefficients of variation of 10% for one method performed by several laboratories and 22% for all methods performed by all laboratories. It is concluded that the majority of laboratories do not meet the clinically desirable intralaboratory precision and that an unacceptably high interlaboratory precision exists.

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