Fuzzy duration forecast model for wind turbine construction project subject to the impact of wind uncertainty

The motion picture industry is one of the largest industries worldwide and has significant importance in the global economy. Considering the high stakes and high risks in the industry, forecast models and decision support systems are gaining importance. Several attempts have been made to estimate the theatrical performance of a movie before or at the early stages of its release. Nevertheless, these models are mostly used for predicting domestic performances and the industry still struggles to predict box office performances in overseas markets. In this study, the aim is to design a forecast model using different machine learning algorithms to estimate the theatrical success of US movies in Turkey. From various sources, a dataset of 1559 movies is constructed. Firstly, independent variables are grouped as pre-release, distributor type, and international distribution based on their characteristic. The number of attendances is discretized into three classes. Four popular machine learning algorithms, artificial neural networks, decision tree regression and gradient boosting tree and random forest are employed, and the impact of each group is observed by compared by the performance models. Then the number of target classes is increased into five and eight and results are compared with the previously developed models in the literature.

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Impact of the Wind Turbine on the Parameters of the Electricity Supply to an Agricultural Farm

Sustainability ◽

10.3390/su13137279 ◽

2021 ◽

Vol 13 (13) ◽

pp. 7279

Author(s):

Zbigniew Skibko ◽

Magdalena Tymińska ◽

Wacław Romaniuk ◽

Andrzej Borusiewicz

Keyword(s):

Power Plant ◽

Wind Turbine ◽

Wind Power ◽

Rural Areas ◽

Power Plants ◽

Reactive Power ◽

Supply Voltage ◽

Common Source ◽

Voltage Fluctuations ◽

The Impact

Wind power plants are an increasingly common source of electricity located in rural areas. As a result of the high variability of wind power, and thus the generated power, these sources should be classified as unstable sources. In this paper, the authors attempted to determine the impact of wind turbine operation on the parameters of electricity supplied to farms located near the source. As a result of the conducted field tests, variability courses of the basic parameters describing the supply voltage were obtained. The influence of power plant variability on the values of voltage, frequency, and voltage distortion factor was determined. To estimate the capacity of the transmission lines, the reactive power produced in the power plant and its effect on the value of the power factor were determined. The conducted research and analysis showed that the wind power plant significantly influences voltage fluctuations in its immediate vicinity (the maximum value registered was close to 2%, while the value required by law was 2.5%). Although all the recorded values are within limits specified by the current regulations (e.g., the THD value is four times lower than the required value), wind turbines may cause incorrect operation of loads connected nearby. This applies mainly to cases where consumers sensitive to voltage fluctuations are installed in the direct vicinity of the power plant.

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Autism Tsunami: the Impact of Rising Prevalence on the Societal Cost of Autism in the United States

Journal of Autism and Developmental Disorders ◽

10.1007/s10803-021-05120-7 ◽

2021 ◽

Author(s):

Mark Blaxill ◽

Toby Rogers ◽

Cynthia Nevison

Keyword(s):

Forecast Model ◽

The United States ◽

Population Projections ◽

Base Case ◽

Prevention Strategies ◽

Total Base ◽

Cost Categories ◽

The Cost ◽

The Impact ◽

First Time

AbstractThe cost of ASD in the U.S. is estimated using a forecast model that for the first time accounts for the true historical increase in ASD. Model inputs include ASD prevalence, census population projections, six cost categories, ten age brackets, inflation projections, and three future prevalence scenarios. Future ASD costs increase dramatically: total base-case costs of $223 (175–271) billion/year are estimated in 2020; $589 billion/year in 2030, $1.36 trillion/year in 2040, and $5.54 (4.29–6.78) trillion/year by 2060, with substantial potential savings through ASD prevention. Rising prevalence, the shift from child to adult-dominated costs, the transfer of costs from parents onto government, and the soaring total costs raise pressing policy questions and demand an urgent focus on prevention strategies.

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Exploring the Relationship between Communication and Success of Construction Projects: The Mediating Role of Conflict

Sustainability ◽

10.3390/su13084513 ◽

2021 ◽

Vol 13 (8) ◽

pp. 4513

Author(s):

Summaira Malik ◽

Muhammad Taqi ◽

José Moleiro Martins ◽

Mário Nuno Mata ◽

João Manuel Pereira ◽

...

Keyword(s):

Project Success ◽

Negative Impact ◽

Positive Impact ◽

Construction Project ◽

Project Team ◽

Relationship Conflict ◽

Team Members ◽

Mediating Role ◽

The Impact

The success of a construction project is a widely discussed topic, even today, and there exists a difference of opinion. The impact of communication and conflict on project success is an important, but least addressed, issue in literature, especially in the case of underdeveloped countries. Miscommunication and conflict not only hinder the success of a project but also may lead to conflicts. The focus of this paper was to examine the impact of communication on project success with the mediating role of conflict. By using SPSS, demographics, descriptive statistics and correlation were determined. Smart PLS version 3.0 was used for confirmatory factor analysis (CFA), internal accuracy and validity estimates, hypothesis checking and mediation testing. The results showed that formal communication has a negative impact on the success of a construction project, resulting in conflicts among project team members, whereas informal communication and communication willingness have a positive impact on project success because people tend to know each other, and trust is developed. Task, process and relationship conflicts were used as mediating variables. It was found that task conflict effects the relations positively because project team members suggest different ways to do a certain task, and, hence, project success is achieved. On the contrary, process conflict and relationship conflict have a negative impact on communication and project success. Both of these conflicts lead to miscommunication, and project success is compromised. Hence, it is the responsibility of the project manager to enhance communication among project team members and to reduce the detrimental effects of process and relationship conflict on project success.

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Risk analysis and strategic planning on bridge construction works at the toll road procurement projects in Central Java Province

SHS Web of Conferences ◽

10.1051/shsconf/20184902020 ◽

2018 ◽

Vol 49 ◽

pp. 02020

Author(s):

Hery Suliantoro ◽

Nurul Fitriani ◽

Bagus Hario Setiadji

Keyword(s):

Avoidance Response ◽

Construction Projects ◽

Construction Project ◽

Weather Forecast ◽

Development Project ◽

Response Strategy ◽

Bridge Construction ◽

Risk Response ◽

Toll Road ◽

The Impact

Risk is a condition caused by uncertainty. Risks will occur on any construction project, including bridge construction projects. Efforts that can be taken to minimize the impact of these risks are to engage in risk management activities. This research was conducted on bridge construction work on toll road procurement project in Pejagan-Pemalang, Pemalang-Batang and Salatiga-Kertasura. The purpose of this research is to analyze the risk of bridge development project in toll road project using Risk Breakdown Structure (RBS) method and then the result as database in discussing risk response strategy. The bridge construction project has 36 risks that are divided into six groups: materials and equipment, design, human resources, finance, management, nature and environmental conditions. Bad weather risks are the higest risk and seasonal risk causing temporary work stoppages. This risk-response strategy is avoidance. Short-term avoidance response strategy is to add shift workers, install tents and add additives in the acceleration of the process of maturation of concrete. The long-term avoidance response strategy is to evaluate and rearrange the work schedule by considering the weather forecast report.

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A New Approach for Estimating the Observation Impact in Ensemble–Variational Data Assimilation

Monthly Weather Review ◽

10.1175/mwr-d-17-0252.1 ◽

2018 ◽

Vol 146 (2) ◽

pp. 447-465 ◽

Cited By ~ 12

Author(s):

Mark Buehner ◽

Ping Du ◽

Joël Bédard

Keyword(s):

Data Assimilation ◽

Forecast Error ◽

Forecast Model ◽

Variational Data Assimilation ◽

Observation Error ◽

New Approach ◽

Regional Prediction ◽

Observation Impact ◽

Adjoint Approach ◽

The Impact

Abstract Two types of approaches are commonly used for estimating the impact of arbitrary subsets of observations on short-range forecast error. The first was developed for variational data assimilation systems and requires the adjoint of the forecast model. Comparable approaches were developed for use with the ensemble Kalman filter and rely on ensembles of forecasts. In this study, a new approach for computing observation impact is proposed for ensemble–variational data assimilation (EnVar). Like standard adjoint approaches, the adjoint of the data assimilation procedure is implemented through the iterative minimization of a modified cost function. However, like ensemble approaches, the adjoint of the forecast step is obtained by using an ensemble of forecasts. Numerical experiments were performed to compare the new approach with the standard adjoint approach in the context of operational deterministic NWP. Generally similar results are obtained with both approaches, especially when the new approach uses covariance localization that is horizontally advected between analysis and forecast times. However, large differences in estimated impacts are obtained for some surface observations. Vertical propagation of the observation impact is noticeably restricted with the new approach because of vertical covariance localization. The new approach is used to evaluate changes in observation impact as a result of the use of interchannel observation error correlations for radiance observations. The estimated observation impact in similarly configured global and regional prediction systems is also compared. Overall, the new approach should provide useful estimates of observation impact for data assimilation systems based on EnVar when an adjoint model is not available.

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Dynamics of the Gear Train Set in Wind Turbine

Materials Science Forum ◽

10.4028/www.scientific.net/msf.697-698.701 ◽

2011 ◽

Vol 697-698 ◽

pp. 701-705

Author(s):

D.D. Ji ◽

Y.M. Song ◽

J. Zhang

Keyword(s):

Wind Turbine ◽

Dynamic Model ◽

Harmonic Balance Method ◽

Planetary Gear ◽

Gear Train ◽

Dynamic Responses ◽

Multi Stage ◽

Lumped Parameter ◽

Cartesian Coordinate ◽

The Impact

A lumped-parameter dynamic model for gear train set in wind turbine is proposed to investigate the dynamics of the speed-increasing gear box. The proposed model is developed in a universal Cartesian coordinate, which includes transversal and torsional deflections of each component, time-varying mesh stiffness, gear profile errors and external excitations. By solving the dynamic model, a modal analysis is performed. The results indicate that the modal properties of the multi-stage gear train in wind turbine are similar to those of a single-stage planetary gear set. A harmonic balance method (HBM) is used to obtain the dynamic responses of the gearing system. The responses give insight into the impact of excitations on the vibrations.

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Quantitative analysis of the impact of craft worker availability on construction project safety performance

Construction Innovation ◽

10.1108/ci-10-2015-0050 ◽

2016 ◽

Vol 16 (3) ◽

pp. 307-322 ◽

Cited By ~ 20

Author(s):

Hossein Karimi ◽

Timothy R.B. Taylor ◽

Paul M. Goodrum ◽

Cidambi Srinivasan

Keyword(s):

Regression Analysis ◽

Poisson Regression ◽

Construction Projects ◽

Construction Project ◽

Safety Performance ◽

Content Type ◽

Poisson Regression Analysis ◽

Incident Cases ◽

The Impact ◽

Craft Worker

Purpose This paper aims to quantify the impact of craft worker shortage on construction project safety performance. Design/methodology/approach A database of 50 North American construction projects completed between 2001 and 2014 was compiled by taking information from a research project survey and the Construction Industry Institute Benchmarking and Metrics Database. The t-test and Mann-Whitney test were used to determine whether there was a significant difference in construction project safety performance on projects with craft worker recruiting difficulty. Poisson regression analysis was then used to examine the relationship between craft worker recruiting difficulty and Occupational Safety and Health Administration Total Number of Recordable Incident Cases per 200,000 Actual Direct Work Hours (TRIR) on construction projects. Findings The result showed that the TRIR distribution of a group of projects that reported craft worker recruiting difficulty tended to be higher than the TRIR distribution of a group of projects with no craft worker recruiting difficulty (p-value = 0.004). Moreover, the average TRIR of the projects that reported craft worker recruiting difficulty was more than two times the average TRIR of projects that experienced no craft recruiting difficulty (p-value = 0.035). Furthermore, the Poisson regression analysis demonstrated that there was a positive exponential relationship between craft worker recruiting difficulty and TRIR in construction projects (p-value = 0.004). Research limitations/implications The projects used to construct the database are heavily weighted towards industrial construction. Practical implications There have been significant long-term gains in construction safety within the USA. However, if recent craft shortages continue, the quantitative analyses presented herein indicate a strong possibility that more safety incidents will occur unless the shortages are reversed. Innovative construction means and methods should be developed and adopted to work in a safe manner with a less qualified workforce. Originality/value The Poisson regression model is the first model that quantifiably links project craft worker availability to construction project safety performance.

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Design and analysis of a segmented blade for a 50 MW wind turbine rotor

Wind Engineering ◽

10.1177/0309524x211069393 ◽

2022 ◽

pp. 0309524X2110693

Author(s):

Alejandra S Escalera Mendoza ◽

Shulong Yao ◽

Mayank Chetan ◽

Daniel Todd Griffith

Keyword(s):

Wind Turbine ◽

Large Mass ◽

Turbine Rotor ◽

Bolted Joints ◽

Bonded Joints ◽

Sheer Size ◽

Extreme Scale ◽

The Impact ◽

Adhesive Materials ◽

Wind Turbine Rotor

Extreme-size wind turbines face logistical challenges due to their sheer size. A solution, segmentation, is examined for an extreme-scale 50 MW wind turbine with 250 m blades using a systematic approach. Segmentation poses challenges regarding minimizing joint mass, transferring loads between segments and logistics. We investigate the feasibility of segmenting a 250 m blade by developing design methods and analyzing the impact of segmentation on the blade mass and blade frequencies. This investigation considers various variables such as joint types (bolted and bonded), adhesive materials, joint locations, number of joints and taper ratios (ply dropping). Segmentation increases blade mass by 4.1%–62% with bolted joints and by 0.4%–3.6% with bonded joints for taper ratios up to 1:10. Cases with large mass growth significantly reduce blade frequencies potentially challenging the control design. We show that segmentation of an extreme-scale blade is possible but mass reduction is necessary to improve its feasibility.

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