scholarly journals Automatic calibration of SWMM using NSGA-III and the effects of delineation scale on an urban catchment

2019 ◽  
Vol 21 (5) ◽  
pp. 781-797
Author(s):  
V. Swathi ◽  
K. Srinivasa Raju ◽  
Murari R. R. Varma ◽  
S. Sai Veena
Keyword(s):  
Goodness Of Fit ◽  
Curve Number ◽  
Roughness Coefficient ◽  
Fit Indices ◽  
Drying Time ◽  
Urban Catchment ◽  
Storm Water Management Model ◽  
Catchment Delineation ◽  
Peak Runoff ◽  
Parameter Values

Abstract The study aims at calibration of the storm water management model (SWMM) with non-dominated sorting genetic algorithm-III (NSGA-III) for urban catchment in Hyderabad, India. The SWMM parameters calibrated were Manning's roughness coefficient (N), depression storage for pervious and impervious areas (DP and Di), sub-catchment width (W), curve number (CN), drying time (dry) of soil and percentage of imperviousness (I). The efficacy of calibration was evaluated by comparing the observed and simulated peak flows and runoff using goodness-of-fit indices. The calibration takes into consideration eight event rainfalls resulting in eight calibrated sets. Weights of goodness-of-fit indices were estimated and the best calibrated set was further validated for five continuous rainfalls/runoffs. Simulated runoff volume and peak runoff over the five continuous rainfalls deviated by 7–22% and 2–20% with respect to observed data. Results indicated that parameters calibrated for an event rainfall could be used for continuous rainfall-runoff modelling. The effect of catchment delineation scale on runoff was also studied. The study indicated that output of the model was sensitive to variation in parameter values of infiltration and imperviousness.

scholarly journals The comparison and analysis on optimal status of Best Management Practice (BMP) mixed technique to reduce urban flood discharge in Tehran District 4

2019 ◽  
Author(s):  
Sorush Niknamian
Keyword(s):  
Management Practice ◽  
Curve Number ◽  
Best Management Practice ◽  
Roughness Coefficient ◽  
Urban Flood ◽  
Storm Water Management Model ◽  
Best Management ◽  
Hybrid Techniques ◽  
Flood Discharge ◽  
The Given

Nowadays, damages caused by flood are deemed as one of the important concerns for urban management. This study aims to analyze effects of coefficient of runoff to urban flood using one of the Best Management Practice (BMP) hybrid techniques with respect to change in use of urban lands and development in urban administration to reduce urban flood discharge. District 4 is one of 22 municipal districts in Tehran city as the east water basin with over 61.4km2. In this investigation, runoff coefficient was calculated by means of Geographic Information System (GIS) to determine rise of this coefficient in hydrological computations using of Storm Water Management Model (SWMM) techniques to adjust urban flood. Similarly, the level of effect was evaluated for four parameters of gradient (slope), roughness coefficient, Curve Number (CN), and impermeability on change of use. With respect to results of sensitivity analysis of peak discharge, this system has the maximum sensitivity in terms of parameter of impermeability percent due to change of use so that following to 10% increase in impermeability, the output discharge of hydrograph runoff was increased 15% and due to 10% reduction in impermeability level, output discharge of hydrograph runoff was decreased 19%. Curve Number (CN) has highest sensitivity after parameter of impermeability percent and following to 10% increase in CN parameter, the output discharge of hydrograph runoff was increased 15% while by 10% reduction in roughness coefficient, output discharge of hydrograph runoff was reduced 8%. After implementation of model with the given mixed scenario through comparing of discharge in 10year return period, it was characterized that the maximum reduction rates occurred in output No 2 (26.8%) and output No 7 (54.3%).

scholarly journals The comparison and analysis on optimal status of Best Management Practice (BMP) mixed technique to reduce urban flood discharge in Tehran District 4

2019 ◽  
Author(s):  
Sorush Niknamian
Keyword(s):  
Management Practice ◽  
Curve Number ◽  
Best Management Practice ◽  
Roughness Coefficient ◽  
Urban Flood ◽  
Storm Water Management Model ◽  
Best Management ◽  
Hybrid Techniques ◽  
Flood Discharge ◽  
The Given

Nowadays, damages caused by flood are deemed as one of the important concerns for urban management. This study aims to analyze effects of coefficient of runoff to urban flood using one of the Best Management Practice (BMP) hybrid techniques with respect to change in use of urban lands and development in urban administration to reduce urban flood discharge. District 4 is one of 22 municipal districts in Tehran city as the east water basin with over 61.4km2. In this investigation, runoff coefficient was calculated by means of Geographic Information System (GIS) to determine rise of this coefficient in hydrological computations using of Storm Water Management Model (SWMM) techniques to adjust urban flood. Similarly, the level of effect was evaluated for four parameters of gradient (slope), roughness coefficient, Curve Number (CN), and impermeability on change of use. With respect to results of sensitivity analysis of peak discharge, this system has the maximum sensitivity in terms of parameter of impermeability percent due to change of use so that following to 10% increase in impermeability, the output discharge of hydrograph runoff was increased 15% and due to 10% reduction in impermeability level, output discharge of hydrograph runoff was decreased 19%. Curve Number (CN) has highest sensitivity after parameter of impermeability percent and following to 10% increase in CN parameter, the output discharge of hydrograph runoff was increased 15% while by 10% reduction in roughness coefficient, output discharge of hydrograph runoff was reduced 8%. After implementation of model with the given mixed scenario through comparing of discharge in 10-year return period, it was characterized that the maximum reduction rates occurred in output No 2 (26.8%) and output No 7 (54.3%).

Confirmatory Factor Analysis of the Long and Short Forms of the Worry Domains Questionnaire

2009 ◽  
Vol 25 (4) ◽  
pp. 239-243
Author(s):  
Roberto Nuevo ◽  
Andrés Losada ◽  
María Márquez-González ◽  
Cecilia Peñacoba
Keyword(s):  
Factor Analysis ◽  
Confirmatory Factor Analysis ◽  
Factor Structure ◽  
Goodness Of Fit ◽  
Factorial Validity ◽  
Fit Indices ◽  
Short Forms ◽  
Confirmatory Factor ◽  
Positive Correlations ◽  
Future Work

The Worry Domains Questionnaire was proposed as a measure of both pathological and nonpathological worry, and assesses the frequency of worrying about five different domains: relationships, lack of confidence, aimless future, work, and financial. The present study analyzed the factor structure of the long and short forms of the WDQ (WDQ and WDQ-SF, respectively) through confirmatory factor analysis in a sample of 262 students (M age = 21.8; SD = 2.6; 86.3% females). While the goodness-of-fit indices did not provide support for the WDQ, good fit indices were found for the WDQ-SF. Furthermore, no source of misspecification was identified, thus, supporting the factorial validity of the WDQ-SF scale. Significant positive correlations between the WDQ-SF and its subscales with worry (PSWQ), anxiety (STAI-T), and depression (BDI) were found. The internal consistency was good for the total scale and for the subscales. This work provides support for the use of the WDQ-SF, and potential uses for research and clinical purposes are discussed.

scholarly journals Advanced Graphical–Analytical Method of Pipe Tank Design Integrated with Sensitivity Analysis for Sustainable Stormwater Management in Urbanized Catchments

Water ◽  
2021 ◽  
Vol 13 (8) ◽  
pp. 1035
Author(s):  
Bartosz Szeląg ◽  
Adam Kiczko ◽  
Anna Musz-Pomorska ◽  
Marcin K. Widomski ◽  
Jacek Zaburko ◽  
...  
Keyword(s):  
Sensitivity Analysis ◽  
Analytical Method ◽  
Design Method ◽  
Accurate Method ◽  
Urban Catchment ◽  
Storm Water Management Model ◽  
Catchment Areas ◽  
Calculation Methodology ◽  
Tank Design ◽  
Spatial Plan

Pipe tanks represent important runoff retention elements of urban stormwater systems. They enable us to reduce and retain runoff as well as to mitigate peak flows in the network. Pipe tanks are often taken into account while designing the spatial plan of urban catchment areas. Hence, there is a need to develop a relatively quick and accurate method for pipe tank dimensioning. A graphical–analytical method of designing a pipe tank is presented in the paper. In the assumed methodology, the possibility of employing machine learning for obtaining a more precise error prediction of the proposed pipe tank design method (compared with the tank volume simulations using the storm water management model (SWMM)) are considered. Thus far, this aspect has not been discussed in the literature. In the adopted calculation methodology, sensitivity analysis constitutes an important element, enabling us to assess the influence of the input data assumed for tank design on the dimensions of the outflow devices and the length of the retention chamber.

Psychometric Assessment of the Persian Translated Version of the Romantic Perfectionism Scale Among Couples

2021 ◽  
pp. 003329412110360
Author(s):  
Abbas Abdollahi ◽  
Kelly A. Allen
Keyword(s):  
Content Validity ◽  
Goodness Of Fit ◽  
Factor Loading ◽  
Face Validity ◽  
Fit Indices ◽  
Depression Anxiety Stress Scale ◽  
Confirmatory Factor ◽  
Married Men ◽  
Iranian Version ◽  
Acceptable Internal Consistency

Romantic perfectionismi can be disruptive to relationships, yet no validated measure for assessing romantic perfectionism in Iranian couples has been developed. Therefore, the purpose of this study was to translate and validate the Romantic Perfectionism Scale (RPS) among Iranian couples. Participants in the study were 200 married men and 320 married women from Tehran, Iran, who completed the translated RPS, the Almost Perfect Scale-Revised, and the Depression Anxiety Stress Scale-21 online. Item impact scores were used to calculate face validity. Impact score values for all items were greater than 1.5, signaling appropriate face validity.. The Content Validity Index (CVI) and the Content Validity Ratio (CVR) were used to measure content validity. Values of the CVI were above the cut-off score of 0.7, implying satisfactory content validity of the items. The CVR values were greater than the Lawshe table (0.78) cut-off score, demonstrating that all items were essential. Confirmatory Factor Analysis (CFA) using AMOS software was used to evaluate the construct validity. The results of the goodness of fit indices confirmed the RPS with two subscales (i.e., self-oriented romantic perfectionism and other-oriented romantic perfectionism) as per the original scale. All items remained in the scale as all factor loading values were greater than 0.45. The findings showed that the two subscales, and the scale as a whole, had acceptable internal consistency, as the construct reliability values for self-oriented romantic perfectionism (0.81), other-oriented romantic perfectionism (0.72), and the whole scale (0.74) were greater than 0.7. The results support the psychometric properties of the Iranian version of the RPS, which could be used by future researchers and clinicians to assess romantic perfectionism in Iranian couples.

scholarly journals Simulation of Low Impact Development (LID) Practices and Comparison with Conventional Drainage Solutions

Proceedings ◽  
2018 ◽  
Vol 2 (11) ◽  
pp. 640 ◽  
Author(s):  
Ioannis M. Kourtis ◽  
Vassilios A. Tsihrintzis ◽  
Evangelos Baltas
Keyword(s):  
Water Management ◽  
Design Process ◽  
Low Impact Development ◽  
Green Roofs ◽  
Storm Water ◽  
Management Model ◽  
Storm Events ◽  
Storm Water Management Model ◽  
Runoff Volume ◽  
Peak Runoff

The present work aims at quantifying the benefit of Low Impact Development (LID) practices in reducing peak runoff and runoff volume, and at comparing LID practices to conventional stormwater solutions. The hydrologic-hydraulic model used was the Storm Water Management Model (SWMM5.1). The LID practices modeled were: (i) Green roofs; and (ii) Permeable pavements. Each LID was tested independently and compared to two different conventional practices, i.e., sewer enlargement and detention pond design. Results showed that for small storm events LID practices are comparable to conventional measures, in reducing flooding. Overall, smaller storms should be included in the design process.

Development of a Uniquely South African Leadership Questionnaire

2002 ◽  
Vol 32 (2) ◽  
pp. 9-25 ◽  
Author(s):  
Hermann H. Spangenberg ◽  
Callie C. Theron
Keyword(s):  
South African ◽  
Goodness Of Fit ◽  
Principal Component ◽  
Charismatic Leadership ◽  
Fit Indices ◽  
Confirmatory Factor Analyses ◽  
Leadership Model ◽  
Emerging Leadership ◽  
Confirmatory Factor ◽  
Unit Performance

This paper describes the development of a leadership questionnaire the aim of which is to assess the behaviours required to lead change and transformation, while at the same time managing organisational unit performance effectively. A Delphi technique was used to facilitate the identification and testing of emerging leadership dimensions and items, starting with a three-stage model of charismatic leadership, The resultant leadership model comprises four stages, measured as 21 dimensions. The research questionnaire consists of 235 items. The questionnaire was field tested by means of 360° assessment conducted amongst 189 unit managers from a diverse group of organisations. Seven hundred and fifty completed questionnaires were obtained. Unrestricted principal component analyses were performed on each of the sub-scales (dimensions) to examine the unidimensionality assumption. This procedure resulted in the formation of three additional sub-scales. Item analyses on each of the sub-scales produced highly satisfactory Cronbach Alpha values. Further confirmatory factor analyses using LISREL were conducted on each of the 24 sub-scales. A series of goodness-of-fit indices generally showed satisfactory results. Overall, results indicate that a 96-item questionnaire format consisting of 24 dimensions with four items each (selected on the basis of factor loadings) could be used with confidence. Recommendations are made for further research.

scholarly journals The Stress and Anxiety to Viral Epidemics-6 items (SAVE-6): A new instrument for assessing anxiety response to viral epidemics in the general population during the COVID-19 pandemic

2021 ◽  
Author(s):  
Seockhoon Chung ◽  
Myung Hee Ahn ◽  
Sangha Lee ◽  
Solbi Kang ◽  
Sooyeon Suh ◽  
...  
Keyword(s):  
General Population ◽  
Goodness Of Fit ◽  
Online Survey ◽  
Fit Indices ◽  
Depression And Anxiety ◽  
Mild Degree ◽  
New Instrument ◽  
Confirmatory Factor ◽  
Good Internal Consistency ◽  
Anxiety Response

During the COVID-19 pandemic, people have reported experiencing anxiety in response to the viral epidemic. This study aimed to explore the validity and usefulness of the Stress and Anxiety to the Viral Epidemic-6 items (SAVE-6) scale for measuring the anxiety response to the viral epidemic of the general population. A total of 1,009 respondents participated in an online survey, and 501 (49.7%) participants were rated as having at least a mild degree of anxiety response to the viral epidemic (SAVE-6 score ≥ 15), whereas 90 (8.9%) and 91 (9.0%) were rated as having depression and anxiety, respectively. The SAVE-6 scales showed good internal consistency (Cronbach’s α = .82). Confirmatory factor analysis supported a one-factor structure for the measure. Goodness-of-fit indices (χ2/df ratio = 19.1, CFI = .92; TLI = .86; SRMR = 0.05; RMSEA = .13) were adequate. The SAVE-6 was found to be a reliable, valid, and useful brief measure that can be applied to the general population. The SAVE-6 may be useful for easily assessing the anxiety symptoms during the pandemic in the general population.

scholarly journals Validity and Reliability of the Amharic Version of the HLS-EU-Q47 Survey Questionnaire among Urban School Adolescents and University students in Dire Dawa, Ethiopia

2020 ◽  
Author(s):  
Hailemariam Mamo Hassen ◽  
Manas Ranjan Behera ◽  
Pratap Kumar Jena ◽  
Sudhir K Kumar Satpathy
Keyword(s):  
Health Literacy ◽  
University Students ◽  
Goodness Of Fit ◽  
Urban School ◽  
Survey Questionnaire ◽  
Fit Indices ◽  
Cronbach’S Alpha ◽  
Cronbach's Alpha ◽  
Dire Dawa ◽  
Ceiling Effects

Abstract Background: Comprehensive tool is not available to assess health literacy status across different languages, contexts and population structures except European health literacy survey scale (HLS-EU-Q47) which is widely used adapted and tested in different countries and languages. However, it was not tested for Ethiopian populations. This study aim was to validate and test the reliability of the Amharic version of the HLS-EU-Q47 survey questionnaire (HLS-Amh) among school adolescents and university students in Dire Dawa, Ethiopia. Method: A cross-sectional study with multistage random sampling was done on urban school adolescents and university students from public schools and Dire Dawa University in Dire Dawa city, Ethiopia, Africa. After translating HLS‐EU‐Q47 into Amharic by translation and back- translation, data was collected using a self-reported questionnaire from samples of 744 participants with 9% non-response rate in October and November, 2018. Confirmatory factor analysis and correlation analysis was done using SPSS and AMOS. Goodness of fit indices, item-scale convergent validity, Pearson correlation coefficient, floor and ceiling effects, Cronbach's alpha and split-half spearman-brown coefficient was computed taking the cut-off values from guidelines and literatures. Ethical issue was contemplated and informed consent was obtained from institutions and participants. Result: Amharic version of HLS- EU-Q47, (HLS-Amh) was reliable but weak for its validity to measure health literacy among urban school adolescents and university students in Dire Dawa, Ethiopia. Goodness-of-fit indices (GFI, AGFI, CFI and IFI) were within range of 0.90-0.80. Although, RMSEA indices were less 0.10, others have made it insufficient to be said as a good model-data fit and was not tolerable for its validity, and the model lacked strength to meet the model-fit indices satisfaction with higher apparent floor/ceiling effects. However, it showed high levels of internal consistency of reliability with relatively higher Cronbach’s alpha coefficient (α=0.910). Conclusions: HLS-Amh was reliable but weak for its validity on these population groups. It can be used for a general survey on awareness and knowledge other than screening substantial and clinical related inquiries. It needs further adaptation and validation for comprehensiveness for demographic, multi-lingual and cultural contexts in Ethiopia.

An empirical study of the antecedents and consequences of brand engagement

2015 ◽  
Vol 33 (4) ◽  
pp. 575-591 ◽  
Author(s):  
Ho Yin Wong ◽  
Bill Merrilees
Keyword(s):  
Structural Equation ◽  
Goodness Of Fit ◽  
Fit Indices ◽  
Brand Performance ◽  
Content Type ◽  
Explanatory Variables ◽  
Brand Engagement ◽  
Consumer Perspective ◽  
Antecedents And Consequences ◽  
New Perspective

Purpose – The purpose of this paper is to develop and empirically test a model of brand engagement. More specifically, the aim is to evaluate both antecedents and consequences of brand engagement, from a management perspective. Design/methodology/approach – A quantitative survey of 403 firms is undertaken to test the model. Structural equation modelling (SEM) is used to estimate the parameters of the model. Findings – A reliable and valid measure of brand engagement is established. The SEM model works well, in terms of goodness of fit indices. The results demonstrate that there are major brand performance benefits (consequences) of brand engagement. Additionally, and important for the practical implications, the results show that brand orientation is a major antecedent to brand engagement. Research limitations/implications – The study needs to be replicated in other countries, with scope to add other explanatory variables for influencing brand engagement. The results have considerable practical benefits for guiding the introduction of measures to enhance brand engagement. Originality/value – The study builds on earlier (mainly consumer) conceptual approaches to brand engagement, but goes further in that it provides empirical evidence about the nature, antecedents and consequences of brand engagement and further, offers a management rather than consumer perspective. Essentially, the study reveals a new perspective of factors that encourage firms to connect/engage their brands with consumers. Brand engagement is a dual concept, reflecting both a consumer and a firm perspective.

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