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Open Access
Article
Publication date: 5 November 2020

Hongyuan Wang and Jingcheng Wang

The purpose of this paper aims to design an optimization control for tunnel boring machine (TBM) based on geological identification. For unknown geological condition, the authors…

Abstract

Purpose

The purpose of this paper aims to design an optimization control for tunnel boring machine (TBM) based on geological identification. For unknown geological condition, the authors need to identify them before further optimization. For fully considering multiple crucial performance of TBM, the authors establish an optimization problem for TBM so that it can be adapted to varying geology. That is, TBM can operate optimally under corresponding geology, which is called geology-adaptability.

Design/methodology/approach

This paper adopted k-nearest neighbor (KNN) algorithm with modification to identify geological conditions. The modification includes adjustment of weights in voting procedure and similarity distance measurement, which at suitable for engineering and enhance accuracy of prediction. The authors also design several key performances of TBM during operation, and built a multi-objective function. Further, the multi-objective function has been transformed into a single objective function by weighted-combination. The reformulated optimization was solved by genetic algorithm in the end.

Findings

This paper provides a support for decision-making in TBM control. Through proposed optimization control, the advance speed of TBM has been enhanced dramatically in each geological condition, compared with the results before optimizing. Meanwhile, other performances are acceptable and the method is verified by in situ data.

Originality/value

This paper fulfills an optimization control of TBM considering several key performances during excavating. The optimization is conducted under different geological conditions so that TBM has geological-adaptability.

Details

Journal of Intelligent Manufacturing and Special Equipment, vol. 1 no. 1
Type: Research Article
ISSN: 2633-6596

Keywords

Open Access
Article
Publication date: 21 July 2020

Kamran Pazand and Kaveh Pazand

The chemical analysis of wells in the Ardabil area, Ardabil Province NW of Iran, was evaluated to determine the hydrogeochemical processes and ion concentration background in the…

Abstract

Purpose

The chemical analysis of wells in the Ardabil area, Ardabil Province NW of Iran, was evaluated to determine the hydrogeochemical processes and ion concentration background in the region. The purpose of this study is to analyze the hydrochemical quality of groundwater in Ardabil aquifer in order to assess the suitability of the waters for different uses.

Design/methodology/approach

The chemical analysis of 75 water wells in the Ardabil area, was evaluated. Over the entire area, the dominated hydrochemical types are: Na-Cl, Na-HCO3-Cl-Mg, Ca-SO4, Ca-Mg-SO4-Cl and Ca-Mg-HCO3. The abundance of the major ions is as follows: Na+>Ca2+>Mg2+>K+ and SO42–> Cl>HCO3 and major ion concentrations are below the acceptable level for drinking water. Most of groundwater samples fell in the soft water category. All of groundwaters belong to the excellent category and can be used safely for irrigation.

Findings

The chemical analysis of 75 water wells in the Ardabil area, Ardabil Province NW of Iran, was evaluated to determine the hydrogeochemical processes and ion concentration background in the region. Over the entire area, the dominated hydrochemical types are: Na-Cl, Na-HCO3-Cl-Mg, Ca-SO4, Ca-Mg-SO4-Cl and Ca-Mg-HCO3. The abundance of the major ions is as follows: Na+>Ca2+>Mg2+>K+ and SO42–> Cl>HCO3 and major ion concentrations are below the acceptable level for drinking water. Most of groundwater samples fell in the soft water category. All of groundwaters belong to the excellent category and can be used safely for irrigation.

Originality/value

The chemical analysis of 75 water wells in the Ardabil area, Ardabil Province NW of Iran, was evaluated to determine the hydrogeochemical processes and ion concentration background in the region. Over the entire area, the dominated hydrochemical types are: Na-Cl, Na-HCO3-Cl-Mg, Ca-SO4, Ca-Mg-SO4-Cl and Ca-Mg-HCO3. The abundance of the major ions is as follows: Na+>Ca2+>Mg2+>K+ and SO42–> Cl>HCO3 and major ion concentrations are below the acceptable level for drinking water. Most of groundwater samples fell in the soft water category. All of groundwaters belong to the excellent category and can be used safely for irrigation.

Details

Ecofeminism and Climate Change, vol. 1 no. 3
Type: Research Article
ISSN: 2633-4062

Keywords

Open Access
Article
Publication date: 31 December 2020

Cheng-Wei Lin, Wan-Chi Jackie Hsu and Hui-Ju Su

The shipper selects a suitable shipping route and plans for a voyage in order to import and export cargo on the basis of published sailing schedules. The reliability of the…

Abstract

The shipper selects a suitable shipping route and plans for a voyage in order to import and export cargo on the basis of published sailing schedules. The reliability of the sailing schedule will influence the shipper’s logistics expense, which means that the logistics costs will depend on the reliability of schedules published by container shipping companies. Therefore, it is important to consider factors which can cause delays would for container ships sailing on sea routes. The reliability of published sailing schedules can be affected by a number of different factors. This study adopts the multi-criteria decision making (MCDM) method to estimate the importance of the delaying factors in a sailing schedule. In addition, the consistent fuzzy preference relations (CFPR) method is applied to identify the subjective importance (weights) of the delaying factors. The entropy weight method combined with the actual performance of the container shipping company are both used when estimating the objective importance (weights) of the delaying factors. According to the analysis results, the criteria can be divided into four quadrants with different management implications, which indicate that instructions for chase strategy, sailing schedule control, fleet allocation, transship operation arrangement and planning for ports in routes are often ignored by container shipping companies. Container shipping companies should consider adjusting their operational strategies, which would greatly improve their operational performance.

Details

Journal of International Logistics and Trade, vol. 18 no. 4
Type: Research Article
ISSN: 1738-2122

Keywords

Open Access
Article
Publication date: 11 April 2023

Wenhao Yi, Mingnian Wang, Jianjun Tong, Siguang Zhao, Jiawang Li, Dengbin Gui and Xiao Zhang

The purpose of the study is to quickly identify significant heterogeneity of surrounding rock of tunnel face that generally occurs during the construction of large-section rock…

Abstract

Purpose

The purpose of the study is to quickly identify significant heterogeneity of surrounding rock of tunnel face that generally occurs during the construction of large-section rock tunnels of high-speed railways.

Design/methodology/approach

Relying on the support vector machine (SVM)-based classification model, the nominal classification of blastholes and nominal zoning and classification terms were used to demonstrate the heterogeneity identification method for the surrounding rock of tunnel face, and the identification calculation was carried out for the five test tunnels. Then, the suggestions for local optimization of the support structures of large-section rock tunnels were put forward.

Findings

The results show that compared with the two classification models based on neural networks, the SVM-based classification model has a higher classification accuracy when the sample size is small, and the average accuracy can reach 87.9%. After the samples are replaced, the SVM-based classification model can still reach the same accuracy, whose generalization ability is stronger.

Originality/value

By applying the identification method described in this paper, the significant heterogeneity characteristics of the surrounding rock in the process of two times of blasting were identified, and the identification results are basically consistent with the actual situation of the tunnel face at the end of blasting, and can provide a basis for local optimization of support parameters.

Details

Railway Sciences, vol. 2 no. 1
Type: Research Article
ISSN: 2755-0907

Keywords

Open Access
Article
Publication date: 21 May 2018

Jue Li, Minghui Yu and Hongwei Wang

On shield tunnel construction (STC) site, human error is widely recognized as essential to accident. It is necessary to explain which factors lead to human error and how these…

1773

Abstract

Purpose

On shield tunnel construction (STC) site, human error is widely recognized as essential to accident. It is necessary to explain which factors lead to human error and how these factors can influence human performance. Human reliability analysis supports such necessity through modeling the performance shaping factors (PSFs). The purpose of this paper is to establish and validate a PSF taxonomy for the STC context.

Design/methodology/approach

The approach taken in this study mainly consists of three steps. First, a description of the STC context is proposed through the analysis of the STC context. Second, the literature which stretch across the PSF methodologies, cognitive psychology and human factors of STC and other construction industries are reviewed to develop an initial set of PSFs. Finally, a final PSF set is modified and validated based on STC task analysis and STC accidents cases.

Findings

The PSF taxonomy constituted by 4 main components, 4 hierarchies and 85 PSFs is established for human behavior modeling and simulation under the STC context. Furthermore, by comparing and evaluating the performance of STC PSF and existing PSF studies, the proposed PSF taxonomy meets the requirement for qualitative and quantitative analysis.

Practical implications

The PSF taxonomy can provide a basis and support for human behavior modeling and simulation under the STC context. Integrating PSFs into a behavior simulation model provides a more realistic and integrated assessment of human error by manifesting the influence of each PSFs on the cognitive processes. The simulation results can suggest concrete points for the improvement of STC safety management.

Originality/value

This paper develops a taxonomy of PSFs that addresses the various unique influences of the STC context on human behaviors. The harsh underground working conditions and diverse resources of system information are identified as key characteristics of the STC context. Furthermore, the PSF taxonomy can be integrated into a human cognitive behavior model to predict the worker’s behavior on STC site in future work.

Details

Engineering, Construction and Architectural Management, vol. 25 no. 4
Type: Research Article
ISSN: 0969-9988

Keywords

Open Access
Article
Publication date: 31 December 2010

Bakhodyr Khodjaev and Se Kwang Oh

Advantage of its geologic location lying at the heart of Central Asia with a large internal market of 27 million people and easy access to CIS market of over 142 million people…

Abstract

Advantage of its geologic location lying at the heart of Central Asia with a large internal market of 27 million people and easy access to CIS market of over 142 million people enables Uzbekistan to form the hub of the region. Its transport and communications networks are connected with the other Central Asian countries. FIEZ in Navoi would be the representative model in CIS and be built on the best practice of next generation model as special national economic zones. Considering that the most of modern business is made through the web connection basis even for the flight management, cargo trace and other controls and operations, the importance of web connection should be stable, reliable and affordable for tenants and business entities at the FIEZ in Navoi. In these regards, cooperation work of both countries to study more details mentioned in this paper as well as other applicable models from Korean Free Economic Zone cases for the full picture of execution and promotion of the FIEZ in Navoi, Uzbekistan is considered.

Details

Journal of International Logistics and Trade, vol. 8 no. 2
Type: Research Article
ISSN: 1738-2122

Keywords

Open Access
Article
Publication date: 1 September 2020

Wendy Chepkemei Rop

The purpose of this paper is to model the impact of geotourism on geoconservation by observing two popular geotourism activities, namely, rock climbing and hiking. It proposes…

1281

Abstract

Purpose

The purpose of this paper is to model the impact of geotourism on geoconservation by observing two popular geotourism activities, namely, rock climbing and hiking. It proposes that as much as geotourism activities have potential negative impacts, they can also bring about positive modification of critical ecosystems like that of Hell’s Gate National Park.

Design/methodology/approach

This research opted for an exploratory research design using both open and close-ended questionnaires from 351 respondents and was complemented by documentary analysis. The statistical relationship between geotourism activities and geoconservation was modelled through linear regression.

Findings

As predicted the computation using hiking and rock climbing to predict geoconservation were significant with p = 0.004 < 0.05 and p = 0.002 < 0.05, respectively. Implying that selected geotourism activity(s) are positively related to geoconservation

Practical implications

Recognizing the symbiotic relationship, values and relevance of geotourism to geoconservation as a dynamic approach to preservation of protected area management is central to promoting ecosystem stewardship and contributes to the achievement of United Nations development goals.

Originality/value

This paper fulfils an identified need to study how geotourism activities can be used to preserve/conserve the ecological environments and geoheritage of a destination

Details

Ecofeminism and Climate Change, vol. 2 no. 1
Type: Research Article
ISSN: 2633-4062

Keywords

Open Access
Article
Publication date: 21 November 2023

Ping Li, Rui Xue, Sai Shao, Yuhao Zhu and Yi Liu

In recent years, railway systems worldwide have faced challenges such as the modernization of engineering projects, efficient management of intelligent digital railway equipment…

1249

Abstract

Purpose

In recent years, railway systems worldwide have faced challenges such as the modernization of engineering projects, efficient management of intelligent digital railway equipment, rapid growth in passenger and freight transport demands, customized transport services and ubiquitous transport safety. The transformation toward intelligent digital transformation in railways has emerged as an effective response to the formidable challenges confronting the railway industry, thereby becoming an inevitable global trend in railway development.

Design/methodology/approach

This paper, therefore, conducts a comprehensive analysis of the current state of global railway intelligent digital transformation, focusing on the characteristics and applications of intelligent digital transformation technology. It summarizes and analyzes relevant technologies and applicable scenarios in the realm of railway intelligent digital transformation, theoretically elucidating the development process of global railway intelligent digital transformation and, in practice, providing guidance and empirical examples for railway intelligence and digital transformation.

Findings

Digital and intelligent technologies follow a wave-like pattern of continuous iterative evolution, progressing from the early stages, to a period of increasing attention and popularity, then to a phase of declining interest, followed by a resurgence and ultimately reaching a mature stage.

Originality/value

The results offer reference and guidance to fully leverage the opportunities presented by the latest wave of the digitalization revolution, accelerate the overall upgrade of the railway industry and promote global collaborative development in railway intelligent digital transformation.

Details

Railway Sciences, vol. 2 no. 4
Type: Research Article
ISSN: 2755-0907

Keywords

Open Access
Article
Publication date: 15 November 2022

Zhiqiang Zhang, Xingyu Zhu and Ronghua Wei

Large displacement misalignment under the action of active faults can cause complex three-dimensional deformation in subway tunnels, resulting in severe damage, distortion and…

Abstract

Purpose

Large displacement misalignment under the action of active faults can cause complex three-dimensional deformation in subway tunnels, resulting in severe damage, distortion and misalignment. There is no developed system of fortification and related codes to follow. There are scientific problems and technical challenges in this field that have never been encountered in past research and practices.

Design/methodology/approach

This paper adopted a self-designed large-scale active fault dislocation simulation loading system to conduct a similar model test of the tunnel under active fault dislocation based on the open-cut tunnel project of the Urumqi Rail Transit Line 2, which passes through the Jiujiawan normal fault. The test simulated the subway tunnel passing through the normal fault, which is inclined at 60°. This research compared and analyzed the differences in mechanical behavior between two types of lining section: the open-cut double-line box tunnel and the modified double-line box arch tunnel. The structural response and failure characteristics of the open-cut segmented lining of the tunnel under the stick-slip part of the normal fault were studied.

Findings

The results indicated that the double-line box arch tunnel improved the shear and longitudinal bending performance. Longitudinal cracks were mainly distributed in the baseplate, wall foot and arch foot, and the crack position was basically consistent with the longitudinal distribution of surrounding rock pressure. This indicated that the longitudinal cracks were due to the large local load of the cross-section of the structure, leading to an excessive local bending moment of the structure, which resulted in large eccentric failure of the lining and formation of longitudinal cracks. Compared with the ordinary box section tunnel, the improved double-line box arch tunnel significantly reduced the destroyed and damage areas of the hanging wall and footwall. The damage area and crack length were reduced by 39 and 59.3%, respectively. This indicates that the improved double-line box arch tunnel had good anti-sliding performance.

Originality/value

This paper adopted a self-designed large-scale active fault dislocation simulation loading system to conduct a similar model test of the tunnel under active fault dislocation. This system increased the similarity ratio of the test model, improved the dislocation loading rate and optimized the simulation scheme of the segmented flexible lining and other key factors affecting the test. It is of great scientific significance and engineering value to investigate the structure of subway tunnels under active fault misalignment, to study its force characteristics and damage modes, and to provide a technical reserve for the design and construction of subway tunnels through active faults.

Details

Railway Sciences, vol. 1 no. 2
Type: Research Article
ISSN: 2755-0907

Keywords

Open Access
Article
Publication date: 14 September 2015

Alina Zajadacz

The purpose of this paper is to present the results of a critical analysis of the disability models developed to date and of how they function in practice. Furthermore, it aims to…

18762

Abstract

Purpose

The purpose of this paper is to present the results of a critical analysis of the disability models developed to date and of how they function in practice. Furthermore, it aims to answer the following question: which model of disability (MD) will provide the most suitable foundation for any course of action undertaken in the process of planning accessible tourism development in the future?

Design/methodology/approach

In the first stage of the study a critical analysis of the MDs described in the literature as well as in selected reports and expert opinions relating to people with disability (PwD) was performer. These findings then became the basis for the second stage of the study which focuses on identifying attitudes within society towards the types of tourism on offer connected to the analysed MDs. The applied research methods include an analysis of a survey (2013, 2014) carried out face-to-face and on the SurveyMonkey web site. The study group consisted of 619 people (from Poland, Russia, Germany, Portugal, Slovakia, Canada, Tunisia and Great Britain).

Findings

The great diversity of disabilities makes finding a universal solution in the creation of accessible tourism supply a complex task. This supports the need for a flexible “mix of various models” aimed at finding optimal solutions and the personalisation of tourism. In this context the greatest potential in the development of accessible tourism are models which are a synthesis of many determiners of disability such as the biopsychosocial or the geographical model of disability. The dynamics of accessible tourism development is likely to be increasingly influenced by the economic model, reflecting current trends for the personalisation of tourism supply.

Research limitations/implications

The survey was carried out mainly within the European Community, the exception being respondents from Irkutsk in eastern (Asian) Russia. In order to gain a global view of the development of accessible tourism, research should be performed in countries representing all continents or tourist regions. Additionally, reflecting the definition of accessible tourism its beneficiaries – PwD – should participate in decision-making processes. Tourism service providers who are directly engaged in tourism supply also have a role to play. Their opinions and attitudes towards the development of accessible tourism determine its very nature in reality.

Practical implications

The survey on attitudes in society regarding the organisation of tourist trips for PwD confirmed conclusions from the analysis of the practical implications of various disability models in the creation of tourism supply that a single universal, optimal solution does not exist. All of the described MD can be applied in the development of a diverse tourism supply. The proposed model “diversification of supply […]” is the theoretical basis for the conscious development of accessible tourism in practice which in accordance with changes observed in the tourism market is undergoing increasing diversification and personalisation.

Social implications

In each of the tourism supply for PwD types the economic model of disability based on the identification of PwD needs and surrounding society is important. The number of PwD and the scope of necessary services, social support (PwD often travel accompanied by one to three people) is determined by income in all the sectors identified in the structure of tourism supply. From the economic point of view, awareness of different types of disability and the diverse models describing it are significant aids in the segmentation of tourism supply and placement of products accessible to PwD on the tourism market.

Originality/value

The paper presents a new, critical perspective on the selected MD, the key to which is the search for optimal solutions in the development of accessible tourism. The analysis performed indicated the need for a synthesis of paradigms at the core of the conceptualisation of particular models, including those often regarded as being contrary (medical and social). The results of studies would give tourism providers important data on an increasingly competitive tourism market, and also affect changes in how PwD, the elderly, are viewed, from the category of “relatively poor” to “attractive, using a wide range of services”.

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