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Article
Publication date: 12 August 2020

Jinsong Tu, Yuanzhen Liu, Ming Zhou and Ruixia Li

This paper aims to predict the 28-day compressive strength of recycled thermal insulation concrete more accurately.

Abstract

Purpose

This paper aims to predict the 28-day compressive strength of recycled thermal insulation concrete more accurately.

Design/methodology/approach

The initial weights and thresholds of BP neural network are improved by genetic algorithm on MATLAB 2014 a platform.

Findings

Genetic algorithm–back propagation (GA-BP) neural network is more stable. The generalization performance of the complex is better.

Originality/value

The GA-BP neural network based on the training sample data can better realize the strength prediction of recycled aggregate thermal insulation concrete and reduce the complex orthogonal experimental process. GA-BP neural network is more stable. The generalization performance of the complex is better.

Details

Journal of Engineering, Design and Technology , vol. 19 no. 2
Type: Research Article
ISSN: 1726-0531

Keywords

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Article
Publication date: 14 November 2016

Matti Kuittinen

This study investigates the carbon footprint of the alternative structure types and materials used for the reconstruction of schools in Haiti. Are recycled construction…

Abstract

Purpose

This study investigates the carbon footprint of the alternative structure types and materials used for the reconstruction of schools in Haiti. Are recycled construction materials more environmental than virgin materials? To estimate which alternative construction solution has the smallest carbon footprint, a survey was made for the school model used for the reconstruction programme in Haiti after the 2010 earthquake.

Design/methodology/approach

The carbon footprint was calculated using life cycle assessment methodology for five different concrete structure alternatives and five different cement mixes for the same design of a school building. In addition, the uptake of CO2 through the carbonation of concrete during 50 years was calculated.

Findings

The carbon footprint of recycled materials can be either the best or worst option, depending on how the materials are used. The difference to using virgin materials is not big. This is mainly due to the lower structural performance of recycled materials, which needs to be compensated for by using additional reinforcements. Using cement mixes that have high amounts of substitutes for cement seems to lower the carbon footprint of structures considerably. The uptake of CO2 in carbonation has potential but requires an optimal design and environment.

Originality/value

The findings give information for humanitarian project managers and designers on lowering the carbon footprint of their construction projects.

Details

International Journal of Disaster Resilience in the Built Environment, vol. 7 no. 5
Type: Research Article
ISSN: 1759-5908

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Article
Publication date: 12 October 2012

Ruixia Yan, Jinliang Liu and Bingxue Yao

The purpose of this paper is to present research methods in processing uncertain information.

Abstract

Purpose

The purpose of this paper is to present research methods in processing uncertain information.

Design/methodology/approach

Vague set and rough set are both‐wings‐mode for expressing uncertainty systems, and based on the both‐wings‐mode of expressing uncertainty systems, the connections of vague set and rough set are discussed.

Findings

This paper presents the relationships between vague set and rough set.

Research limitations/implications

Based on these connections between vague set and rough set, theoretical and means of vague set can be used for rough set; also theoretical and means of rough set can be used for vague set.

Originality/value

The paper contributes to the discussion on the research of vague set and rough set. The conclusions are useful in information processing.

Details

Kybernetes, vol. 41 no. 9
Type: Research Article
ISSN: 0368-492X

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Article
Publication date: 24 April 2020

Ariel Mutegi Mbae and Nnamdi I. Nwulu

In the daily energy dispatch process in a power system, accurate short-term electricity load forecasting is a very important tool used by spot market players. It is a…

Abstract

Purpose

In the daily energy dispatch process in a power system, accurate short-term electricity load forecasting is a very important tool used by spot market players. It is a critical requirement for optimal generator unit commitment, economic dispatch, system security and stability assessment, contingency and ancillary services management, reserve setting, demand side management, system maintenance and financial planning in power systems. The purpose of this study is to present an improved grey Verhulst electricity load forecasting model.

Design/methodology/approach

To test the effectiveness of the proposed model for short-term load forecast, studies made use of Kenya’s load demand data for the period from January 2014 to June 2019.

Findings

The convectional grey Verhulst forecasting model yielded a mean absolute percentage error of 7.82 per cent, whereas the improved model yielded much better results with an error of 2.96 per cent.

Practical implications

In the daily energy dispatch process in a power system, accurate short-term load forecasting is a very important tool used by spot market players. It is a critical ingredient for optimal generator unit commitment, economic dispatch, system security and stability assessment, contingency and ancillary services management, reserve setting, demand side management, system maintenance and financial planning in power systems. The fact that the model uses actual Kenya’s utility data confirms its usefulness in the practical world for both economic planning and policy matters.

Social implications

In terms of generation and transmission investments, proper load forecasting will enable utilities to make economically viable decisions. It forms a critical cog of the strategic plans for power utilities and other market players to avoid a situation of heavy stranded investment that adversely impact the final electricity prices and the other extreme scenario of expensive power shortages.

Originality/value

This research combined the use of natural logarithm and the exponential weighted moving average to improve the forecast accuracy of the grey Verhulst forecasting model.

Details

Journal of Engineering, Design and Technology , vol. 18 no. 5
Type: Research Article
ISSN: 1726-0531

Keywords

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Article
Publication date: 4 January 2013

Gokhan Bayar

The purpose of this paper is to present work which is a part of the Comprehensive Automation for Specialty Crops project (CASC). Desired trajectory tracking objective has…

Abstract

Purpose

The purpose of this paper is to present work which is a part of the Comprehensive Automation for Specialty Crops project (CASC). Desired trajectory tracking objective has been previously performed by using a non‐model based approach in this project. Long distance autonomous drive has been achieved; however the results haven't met the expectations of the project requirements. In order to provide these requirements, this study is conducted. In this study, long distance autonomous trajectory tracking for an orchard vehicle is studied. Besides longitudinal motion, lateral motion of the vehicle is also considered. The longitudinal and lateral errors are objected to keep into a region of less than 10 cm.

Design/methodology/approach

Car‐like robot kinematic modeling approach is used to create desired trajectory. In order to control longitudinal velocity and steering angle of the vehicle, a controller methodology is proposed. Stability of the controller proposed is shown by using Lyapunov stability approach.

Findings

The proposed model is adapted into a four‐wheeled autonomous orchard vehicle and tested in an experimental orchard for long distance autonomous drives. More than 15 km autonomous drive is successfully achieved and the details are presented in this paper.

Originality/value

In this study, long distance autonomous trajectory tracking for an orchard vehicle is focused. A model based control strategy, including the information about longitudinal and lateral motion of the vehicle, is constructed. A new approach to create steering angles for turning operations of the orchard vehicle is introduced. It is objected that the longitudinal and lateral errors should be less than 10 cm during the trajectory tracking task.

Details

Industrial Robot: An International Journal, vol. 40 no. 1
Type: Research Article
ISSN: 0143-991X

Keywords

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