scholarly journals Dose-response surface fits to drought and nitrogen limitation applied together allow mapping of loci that exhibit nonlinear responses

2017 ◽  
Author(s):  
Megan M. Chang ◽  
Danielle Allery Nail ◽  
Toni Kazic ◽  
Susan J. Simmons ◽  
Ann E. Stapleton
Keyword(s):  
Response Surface ◽  
Dose Response ◽  
Genetic Architecture ◽  
Environmental Changes ◽  
Crop Improvement ◽  
Crop Protection ◽  
Three Dimensional ◽  
Response Surfaces ◽  
Protection Measures ◽  
Different Response

ABSTRACTCrop improvement must accelerate to feed an increasing human population in the face of environmental changes. Breeding programs can include anticipated climatic changes and genetic architecture to optimize improvement strategies. We analyzed the genetic architecture underlying the response of Zea mays to combinations of water and nitrogen stresses. Recombinant inbreds were subjected to nine combinations of the two stresses using an optimized response surface design, and their growth was measured. Three-dimensional dose response surfaces were fit globally and to each polymorphic allele to determine which genetic markers were associated with different response surfaces. Three quantitative trait loci that produced nonlinear surfaces were mapped. Alleles that performed better in combinations of mid-range stresses were typically not the alleles that performed best under combinations of extreme stresses. To develop physiologically relevant models for future genetic analyses, we modeled the network that explains the response surfaces. The network contains two components, an elliptical paraboloid and a plane, that each combine the nitrogen and water inputs. The relative weighting of the two components and the inputs is governed by five parameters. We estimated parameter values for the smoothed surfaces from the experimental lines using a set of points that covered the most distinctive regions of the three-dimensional surfaces. Surfaces computed using these values reproduced the smoothed experimental surfaces well, especially in the neighborhood of the peaks, as judged by three different criteria. The parameters exaggerated the amplitudes of the simulated surfaces. Experiments using single stresses could misestimate responses to their combinations and disguise loci that respond nonlinearly. The three-dimensional shape evaluation strategy used here more thoroughly compares nonlinear, nonplanar responses. We encourage the application of our findings and methods to experiments that mix crop protection measures, stresses, or both, on elite and landrace germplasm.

PARAMETRIZATION FOR RESPONSE SURFACE IN A DENTAL PROSTHESIS WITH FEM THREE-DIMENSIONAL MODELING

2018 ◽  
Author(s):  
Gabriela Paschoeto ◽  
Camilo Mesquita Neto ◽  
EDSON CAPELLO SOUSA
Keyword(s):  
Response Surface ◽  
Three Dimensional ◽  
Dental Prosthesis ◽  
Three Dimensional Modeling ◽  
Dimensional Modeling

Shape Optimization of Forward-Curved-Blade Centrifugal Fan with Navier-Stokes Analysis

2004 ◽  
Vol 126 (5) ◽  
pp. 735-742 ◽  
Author(s):  
Kwang-Yong Kim ◽  
Seoung-Jin Seo
Keyword(s):  
Response Surface ◽  
Stokes Equations ◽  
Computing Time ◽  
Relative Size ◽  
Three Dimensional ◽  
Navier Stokes ◽  
Centrifugal Fan ◽  
Navier Stokes Equations ◽  
Design Variables ◽  
Curved Blade

In this paper, the response surface method using a three-dimensional Navier-Stokes analysis to optimize the shape of a forward-curved-blade centrifugal fan is described. For the numerical analysis, Reynolds-averaged Navier-Stokes equations with the standard k-ε turbulence model are discretized with finite volume approximations. The SIMPLEC algorithm is used as a velocity–pressure correction procedure. In order to reduce the huge computing time due to a large number of blades in forward-curved-blade centrifugal fan, the flow inside of the fan is regarded as steady flow by introducing the impeller force models. Four design variables, i.e., location of cutoff, radius of cutoff, expansion angle of scroll, and width of impeller, were selected to optimize the shapes of scroll and blades. Data points for response evaluations were selected by D-optimal design, and a linear programming method was used for the optimization on the response surface. As a main result of the optimization, the efficiency was successfully improved. Effects of the relative size of the inactive zone at the exit of impeller and momentum fluxes of the flow in scroll on efficiency were further discussed. It was found that the optimization process provides a reliable design of this kind of fan with reasonable computing time.

Optimization of Trenched Film Cooling Using RSM Coupled CFD

2018 ◽  
Vol 0 (0) ◽  
Author(s):  
V.G. Krishna Anand ◽  
K.M. Parammasivam
Keyword(s):  
Film Cooling ◽  
Three Dimensional ◽  
Response Surfaces ◽  
Test Surface ◽  
Response Factor ◽  
Film Cooling Effectiveness ◽  
Blowing Ratio ◽  
Flow Parameters ◽  
Considerable Impact ◽  
The Impact

AbstractThe trench film cooling employs film holes embedded in a slot created on the surface that requires protection from the impact of hot mainstream flow. The present investigation employs Response Surface Methodology (RSM) approach coupled with CFD analysis to develop a regression predictive model and to optimize the trench geometric and flow parameters viz., trench width (w), trench depth (d), film hole compound angle (β) and blowing ratio (M). The Area-averaged film cooling effectiveness (ȠAA) were chosen as a response factor for RSM and with trench design and flow parameters used as input factors for regression analysis. Analysis of variance (ANOVA) analysis was carried out on the regression model to identify the influence of individual parameters. Three dimensional response surfaces that relate the effect of input parameters on the response factor were analyzed. Experimental results of a case identified from the RSM matrix was found to correlate well with computational investigations. Results from the study indicate that the parameters d, β and M have considerable impact on film cooling performance of test surface with trenches.

scholarly journals Participatory potato seed production: a breakthrough for food security and income generation in the central highlands of Ethiopia

2017 ◽  
Vol 2 (1) ◽  
Author(s):  
Abebe Chindi ◽  
Egata Shunka ◽  
Atsede Solomon ◽  
W. Giorgis Gebremedhin ◽  
Ebrahim Seid ◽  
...  
Keyword(s):  
Information Dissemination ◽  
Agricultural Research ◽  
Crop Protection ◽  
Potato Production ◽  
Sub Saharan Africa ◽  
Potato Seed ◽  
Protection Measures ◽  
Potato Varieties ◽  
Production Technologies ◽  
Sub Saharan

AbstractQuality seed is one of the major bottlenecks hampering the production and productivity of potato not only in Ethiopia but also in Sub-Saharan Africa. Since the 1970’s, the Ethiopian Institute of Agricultural Research has generated a number of improved potato production technologies such as improved varieties with accompanying agronomic practices, crop protection measures, postharvest handling techniques and utilization options. The developed technologies were promoted from 2013-2015 via technology promotion and popularization to the Wolmera, Adea-Bera and Ejere districts with the objective of creating awareness and up scaling of improved potato production and utilization technologies. The Potato Improvement Research Program and the Research and Extension Division of Holetta Research Center in collaboration with extension staff of the Ministry of Agriculture (MoA) undertake this activity. The farmers were selected and organized in Farmer Field Schools and all stakeholders were engaged before distributing potato seeds and planting on selected farmers’ fields for demonstrating of potato production technologies. A total of 899 farmers and 40 agricultural experts were trained and 27.7, 9 and 5.5 tons of quality seeds of Gudanie, Jalenie and Belete potato varieties, respectively, were delivered as a revolving seed with their recommended agronomic packages; this amount of seed covered 21.1 ha. A total of 16 farmer groups from Wolmera, 7 from Adea-Berga, and 11 from Ejere participated. They produced over 434 tons of relatively clean seed and constructed 8 diffused light stores. In addition to the demonstration of improved potato varieties, information dissemination was also an important component of the program to raise awareness for a large numbers of potato growers through farmers’ field days, pamphlets, and mass media. Each year about three field days were organized and more than 1500 pamphlets were distributed to farmers invited from neighboring districts and ‘Kebeles’ to enhance speed. Through this intervention farmers are now harvesting a yield of about 26-34 t/ha up from 8t/ha when they were using inferior quality potato seed; this has made the farmers in the intervention area more food secure especially during the usually food scarce months of August to October when cereal crops are generally yet to mature. The farmers are also getting additional income from the sale of excess potato and are able to better meet other necessary costs like school fees, for their children.

scholarly journals Idiorrhythmic dose-rate variability in dietary zinc intake generates a different response pattern of zinc metabolism than conventional dose–response feeding

1997 ◽  
Vol 78 (1) ◽  
pp. 173-191 ◽  
Author(s):  
Berislav MomČilović ◽  
Philip G. Reeves ◽  
Michael J. Blake
Keyword(s):  
Dose Rate ◽  
Dose Response ◽  
Male Rats ◽  
Metabolic Efficiency ◽  
Zinc Metabolism ◽  
Deficient Diet ◽  
Zinc Intake ◽  
Conventional Dose ◽  
Zn Concentration ◽  
Different Response

We compared the effects of idiorrhythmic dose-rate feeding and conventional dose-response on the induction of intestinal metallothionein (IMT), expression of aortal heat-shock protein mRNA (HSP70mRNA) induced by restraint stress, and accumulation of Zn in the femur and incisor of young growing male rats. An idiorrhythmic approach requires that the average dietary Zn concentration (modulo, M) over the whole experiment (epoch, E) is kept constant across different groups. This is done by adjusting the Zn concentration of the supplemented diet supplied to compensate for the reduction in the number of days on which Zn-supplemented diet is fed, the latter being spread evenly over the experiment. Idiorrhythms involve offering the diet with n times theoverall Zn concentration (M) only every nth day with Zn-deficient diet offered on other days. Idiorrythmic Zn dose-rate feeding changed Zn accumulation in the femur and incisor in a complexbi-modal fashion, indicating that metabolic efficiency of dietary Zn is not constant but depends on Zn dose-rate. In contrast to feeding Zn in the conventional dose-response scheme, iMT and HSP7OmRNA were not affected by idiorrhythmic dose-rate feeding. Idiorrhythmic cycling in dietary Zn load posed no risk of a biochemical overload nor caused the animals to be stressed. Idiorrhythmic dose-rate feeding brings the dimension of time to the conventional dose-response

Assessing Physostigmine Efficacy by Response Surface Modeling: A Comparison to Pyridostigmine Efficacy

1988 ◽  
Vol 7 (7) ◽  
pp. 1013-1030 ◽  
Author(s):  
C. Gennings ◽  
R. A. Carchman ◽  
W. H. Carter ◽  
E. D. Campbell ◽  
R. M. Boyle ◽  
...  
Keyword(s):  
Response Surface ◽  
Confidence Regions ◽  
Atropine Sulfate ◽  
Response Surfaces ◽  
Slope Parameter ◽  
Treatment Combination ◽  
Probability Of Survival ◽  
Point Estimates ◽  
Dose Combination ◽  
Pralidoxime Chloride

The therapeutic efficacy of atropine sulfate/pralidoxime chloride (ATR/2-PAM) treatment therapy and physostigmine (PHY) pretreatment therapy was evaluated in soman-challenged guinea pigs. Response surface analysis (RSM) of treatment efficacy indicated that the optimal ATR/2-PAM dose combination varied as a function of both the soman (GD) challenge level and the PHY pretreatment dose. Efficacy was, therefore, evaluated for varying PHY pretreatment doses in combination with the appropriate optimal ATR/2-PAM treatment (as determined by RSM for each soman challenge dose and PHY dose evaluated). The response surfaces depicting the effects (i.e., probability of survival) of ATR/2-PAM combinations at fixed levels of PHY and GD are presented, and confidence regions and point estimates for optimal ATR/2-PAM treatment combination are included. It was estimated that with optimal therapy a protective ratio (PR) of 6 can be observed. Comparisons were made between the use of PHY/ATR/2-PAM as presented here and the use of PYR/ATR/2-PAM, as discussed by Jones et al.(1) Both studies showed a strong positive (r ≥ 0.98) relationship between dose and the PR. However, the estimated slope parameter for PHY was significantly larger ( P < 0.001) than the slope parameter for pyridostigmine (PYR). This difference in slopes may indicate different mechanisms of action for PYR and PHY.

Development of a Coupled 3D Groundwater-Vegetation Model for Coastal Wetlands

2021 ◽  
Author(s):  
Shuxin Luo ◽  
Ting Fong May Chui
Keyword(s):  
Native Species ◽  
Environmental Changes ◽  
Southern China ◽  
Saline Water ◽  
Three Dimensional ◽  
Mangrove Ecosystem ◽  
Mangrove Forests ◽  
Vegetation Model ◽  
Mangrove Species ◽  
Hydrological Conditions

&lt;p&gt;Mangrove forests are mainly found in the intertidal zone. Their ability to live in saline water enables them to outcompete non-mangrove vegetation in harsh and specific coastal environment. Nevertheless, they can still be invaded by alien mangrove species in suitable hydrological conditions, possibly resulting in more fragile ecosystems. Subtropical mangrove ecosystem demonstrates high variability in mangrove growth and hydrological conditions. However, their interactions are not well-understood, especially for the mangrove interspecific competition in varying groundwater conditions. To address this issue, the present study developed a coupled three-dimensional groundwater-vegetation model based on MANTRA (MANHAM-SUTRA) to simultaneously simulate groundwater hydrodynamics and mangrove distribution. The developed model was then applied to a subtropical mangrove swamp invaded by Sonneratia spp. in Mai Po Nature Reserve, Hong Kong, China. Vegetation domain is updated yearly using the annual mangrove areas extracted from remote-sensing images from 2000 to 2018. Then, multidecadal simulations were performed to validate the model in simulating the interaction between groundwater and mangrove growth. For the piezometric head, all RMS errors are smaller than 0.2 m and the correlation coefficients are larger than 0.86, which proves the effectiveness of the model in groundwater level simulation within Mai Po. The seasonal variations in the groundwater salinity were also well captured in both the fringe forest and the mudflat. The simulated biomass of Sonneratia spp. is mainly distributed at the river outlets, which is also in good agreement with the historical measurements. The validated model can then be used to predict the invasion and the distribution of the exotic mangrove species in the context of future environmental changes for better management of mangrove swamps. Since Sonneratia is a common alien species in southern China, the model can also be used for regional management of mangrove invasion and conservation of native species. The insights obtained from this study may also provide references for other similar studies examining the interaction between coastal groundwater and vegetation.&lt;/p&gt;

Economic Evaluation of Precision Crop Protection Measures

2010 ◽  
pp. 417-426 ◽  
Author(s):  
Jan Ole Schroers ◽  
Roland Gerhards ◽  
Martin Kunisch
Keyword(s):  
Economic Evaluation ◽  
Crop Protection ◽  
Protection Measures

scholarly journals A robust multi response surface approach for optimization of multistage processes

2020 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Amir Moslemi ◽  
Mahmood Shafiee
Keyword(s):  
Robust Optimization ◽  
Response Surface ◽  
Numerical Study ◽  
Ordinary Least Squares ◽  
Response Surfaces ◽  
Estimation Methods ◽  
Design Parameters ◽  
Optimization Approach ◽  
Content Type

PurposeIn a multistage process, the final quality in the last stage not only depends on the quality of the task performed in that stage but is also dependent on the quality of the products and services in intermediate stages as well as the design parameters in each stage. One of the most efficient statistical approaches used to model the multistage problems is the response surface method (RSM). However, it is necessary to optimize each response in all stages so to achieve the best solution for the whole problem. Robust optimization can produce very accurate solutions in this case.Design/methodology/approachIn order to model a multistage problem, the RSM is often used by the researchers. A classical approach to estimate response surfaces is the ordinary least squares (OLS) method. However, this method is very sensitive to outliers. To overcome this drawback, some robust estimation methods have been presented in the literature. In optimization phase, the global criterion (GC) method is used to optimize the response surfaces estimated by the robust approach in a multistage problem.FindingsThe results of a numerical study show that our proposed robust optimization approach, considering both the sum of square error (SSE) index in model estimation and also GC index in optimization phase, will perform better than the classical full information maximum likelihood (FIML) estimation method.Originality/valueTo the best of the authors’ knowledge, there are few papers focusing on quality-oriented designs in the multistage problem by means of RSM. Development of robust approaches for the response surface estimation and also optimization of the estimated response surfaces are the main novelties in this study. The proposed approach will produce more robust and accurate solutions for multistage problems rather than classical approaches.

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