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Open Access
Article
Publication date: 31 August 2012

Ming-Miin Yu, Bo Hsiao, Shih-Hsun Hsu and Shaw Yu Li

This paper presents an alternative approach to evaluating the overall efficiency and performance of Taiwanese container ports. Specifically, a parallel activity with series…

Abstract

This paper presents an alternative approach to evaluating the overall efficiency and performance of Taiwanese container ports. Specifically, a parallel activity with series structure concept in the form of data envelopment analysis (MNDEA) is used to construct a model that applies to three different activities: harbor management, stevedoring and warehousing operations. We will further divide each activity into two process types, production processes and services processes. We will also adopt a Delphi survey approach and use the Analytic Network Process (ANP) to identify these processes’influence dependence and their degree of importance for the MNDEA model setting. An empirical application demonstrates the performance of Taiwanese container ports by using MNDEA with window analysis techniques via the directional distance functionThe results demonstrate that the application is effective in indicating and/or suggesting resource-adjustments, while considering which undesirable output levels and shared inputs were involved. The results also present directions for possible improvements in workplace efficiency.

Open Access
Article
Publication date: 15 November 2022

Liyao Song, Bai Chen, Bo Li, Rupeng Zhu and Dan Wang

The supercritical design of tail rotor drive shaft has attracted more attention in helicopter design due to its high power–weight ratio and low maintenance cost. However, there…

Abstract

Purpose

The supercritical design of tail rotor drive shaft has attracted more attention in helicopter design due to its high power–weight ratio and low maintenance cost. However, there exists excessive vibration when the shaft passes through the critical frequency. Dry friction damper is the equipment applied to the drive shaft to suppress the excessive vibration. In order to figure out the damping mechanism of the dry friction damper and improve the damping efficiency, the dynamic model of the shaft/damper system is established based on the Jeffcott rotor model.

Design/methodology/approach

The typical frequency response of the system is studied through bifurcation diagrams, amplitude-frequency characteristic curves and waterfall frequency response spectrum. The typical transient responses under frequency sweeps are also obtained.

Findings

The results show that the response of the system changes from periodic no-rub motion to quasi-periodic rub-impact motion, and then to synchronous full annular rub-impact, and finally, back to periodic no-rub motion. The slip of the rub-impact ring improves the stability of the system. Besides, the effects of the system parameters including critical dry friction force, rub-impact friction coefficient, initial clearance on the stability and the vibration damping capacity are studied. It is observed that the stability changes significantly varying the three parameters respectively. The vibration damping capacity is mainly affected by the critical dry friction force and the initial clearance.

Originality/value

Presented results provide guidance for the design of the dry friction damper.

Details

Journal of Intelligent Manufacturing and Special Equipment, vol. 3 no. 2
Type: Research Article
ISSN: 2633-6596

Keywords

Open Access
Article
Publication date: 2 June 2023

Junru Zhang, Yumeng Liu and Bo Yan

This study aims to research the large cross-section tunnel stability evaluation method corrected after considering the thickness-span ratio.

Abstract

Purpose

This study aims to research the large cross-section tunnel stability evaluation method corrected after considering the thickness-span ratio.

Design/methodology/approach

First, taking the Liuyuan Tunnel of Huanggang-Huangmei High-Speed Railway as an example and taking deflection of the third principal stress of the surrounding rock at a vault after tunnel excavation as the criterion, the critical buried depth of the large section tunnel was determined. Then, the strength reduction method was employed to calculate the tunnel safety factor under different rock classes and thickness-span ratios, and mathematical statistics was conducted to identify the relationships of the tunnel safety factor with the thickness-span ratio and the basic quality (BQ) index of the rock for different rock classes. Finally, the influences of thickness-span ratio, groundwater, initial stress of rock and structural attitude factors were considered to obtain the corrected BQ, based on which the stability of a large cross-section tunnel with a depth of more than 100 m during mechanized operation was analyzed. This evaluation method was then applied to Liuyuan Tunnel and Cimushan No. 2 Tunnel of Chongqing Urban Expressway for verification.

Findings

This study shows that under different rock classes, the tunnel safety factor is a strict power function of the thickness-span ratio, while a linear function of the BQ to some extent. It is more suitable to use the corrected BQ as a quantitative index to evaluate tunnel stability according to the actual conditions of the site.

Originality/value

The existing industry standards do not consider the influence of buried depth and span in the evaluation of tunnel stability. The stability evaluation method of large section tunnel considering the correction of overburden span ratio proposed in this paper achieves higher accuracy for the stability evaluation of surrounding rock in a full or large-section mechanized excavation of double line high-speed railway tunnels.

Content available
Book part
Publication date: 7 December 2023

Zen Tong Chunhua Zheng and Yali Zou

Abstract

Details

The Significance of Chinatown Development to a Multicultural America: An Exploration of the Houston Chinatowns
Type: Book
ISBN: 978-1-80455-377-0

Open Access
Article
Publication date: 12 October 2023

V. Chowdary Boppana and Fahraz Ali

This paper presents an experimental investigation in establishing the relationship between FDM process parameters and tensile strength of polycarbonate (PC) samples using the…

477

Abstract

Purpose

This paper presents an experimental investigation in establishing the relationship between FDM process parameters and tensile strength of polycarbonate (PC) samples using the I-Optimal design.

Design/methodology/approach

I-optimal design methodology is used to plan the experiments by means of Minitab-17.1 software. Samples are manufactured using Stratsys FDM 400mc and tested as per ISO standards. Additionally, an artificial neural network model was developed and compared to the regression model in order to select an appropriate model for optimisation. Finally, the genetic algorithm (GA) solver is executed for improvement of tensile strength of FDM built PC components.

Findings

This study demonstrates that the selected process parameters (raster angle, raster to raster air gap, build orientation about Y axis and the number of contours) had significant effect on tensile strength with raster angle being the most influential factor. Increasing the build orientation about Y axis produced specimens with compact structures that resulted in improved fracture resistance.

Research limitations/implications

The fitted regression model has a p-value less than 0.05 which suggests that the model terms significantly represent the tensile strength of PC samples. Further, from the normal probability plot it was found that the residuals follow a straight line, thus the developed model provides adequate predictions. Furthermore, from the validation runs, a close agreement between the predicted and actual values was seen along the reference line which further supports satisfactory model predictions.

Practical implications

This study successfully investigated the effects of the selected process parameters - raster angle, raster to raster air gap, build orientation about Y axis and the number of contours - on tensile strength of PC samples utilising the I-optimal design and ANOVA. In addition, for prediction of the part strength, regression and ANN models were developed. The selected ANN model was optimised using the GA-solver for determination of optimal parameter settings.

Originality/value

The proposed ANN-GA approach is more appropriate to establish the non-linear relationship between the selected process parameters and tensile strength. Further, the proposed ANN-GA methodology can assist in manufacture of various industrial products with Nylon, polyethylene terephthalate glycol (PETG) and PET as new 3DP materials.

Details

International Journal of Industrial Engineering and Operations Management, vol. 6 no. 2
Type: Research Article
ISSN: 2690-6090

Keywords

Content available
Book part
Publication date: 14 December 2023

Filippo Marchesani

Abstract

Details

The Global Smart City
Type: Book
ISBN: 978-1-83797-576-1

Open Access
Article
Publication date: 13 September 2023

Siyao Li, Bo Yuan, Yun Bai and Jianfeng Liu

To address the problem that the current train operation mode that train selects one of several offline pre-generated control schemes before the departure and operates following…

Abstract

Purpose

To address the problem that the current train operation mode that train selects one of several offline pre-generated control schemes before the departure and operates following the scheme after the departure, energy-saving performance of the whole metro system cannot be guaranteed.

Design/methodology/approach

A cooperative train control framework is formulated to regulate a novel train operation mode. The classic train four-phase control strategy is improved for generating specific energy-efficient control schemes for each train. An improved brute force (BF) algorithm with a two-layer searching idea is designed to solve the optimisation model of energy-efficient train control schemes.

Findings

Case studies on the actual metro line in Guangzhou, China verify the effectiveness of the proposed train control methods compared with four-phase control strategy under different kinds of train operation scenarios and calculation parameters. The verification on the computation efficiency as well as accuracy of the proposed algorithm indicates that it meets the requirement of online optimisation.

Originality/value

Most existing studies optimised energy-efficient train timetable or train control strategies through an offline process, which has a defect in coping with the disturbance or delays effectively and promptly during real-time train operation. This paper studies an online optimisation of cooperative train control based on the rolling optimisation idea, where energy-efficient train operation can be realised once train running time is determined, thus mitigating the impact of unpredictable operation situations on the energy-saving performance of trains.

Details

Railway Sciences, vol. 2 no. 3
Type: Research Article
ISSN: 2755-0907

Keywords

Content available
Book part
Publication date: 8 August 2017

Abstract

Details

Return of Marxian Macro-Dynamics in East Asia
Type: Book
ISBN: 978-1-78714-477-4

Open Access
Article
Publication date: 26 July 2021

Mauro Dini and Tonino Pencarelli

The purpose of this paper is to conceptually examine the phenomenon of wellness tourism under a holistic and systemic lens, focusing on the offer system and the main components…

15111

Abstract

Purpose

The purpose of this paper is to conceptually examine the phenomenon of wellness tourism under a holistic and systemic lens, focusing on the offer system and the main components necessary for the staging of wellness experiences. This approach to holistic wellbeing within the tourism sector has led to a broadening of the type of services and experiences that make up the value propositions that can positively contribute to people’s wellbeing.

Design/methodology/approach

This study identifies and defines the components of wellness tourism (including sectors not traditionally associated with it) through a review and analysis of the extant literature on “wellness tourism” and “wellbeing tourism” of the past two decades; the components were classified through an open coding process.

Findings

Wellness tourism, as a broad multidimensional concept, is composed by ten different components of the offer system: hot springs, spas, medical tourism, care of the body and mind, enogastronomy, sports, nature and environment, culture, spirituality and events. Each of these categories may represent a single touristic offer targeted to specific market segments, but they may also be one of several components within an integrated mix of tourism products proposed.

Originality/value

A holistic view of wellness tourism has implications for strategic marketing processes. Destination Management Organizations and company managers should segment their demand according to more innovative criteria than what has traditionally been adopted for wellness in terms of health care and medical procedures. Value propositions for tourists should be wellness-driven to satisfy the growing demand for wellness/well-being and should involve the participation of all the various actors and producers within the wellness tourism offer system at wellness destinations.

康养旅游及其组成元素:一个全方位的视角

目的

此一论文会以全面和有系统的目光, 谈及康养旅游的现象, 并集中于康养旅游的供应系统和主要组成元素。此一以全面身心健康为目的的旅游行业, 使不同服务的覆盖范围和经验得以扩而充之, 提供有利条件正面地影响着人们的身心健康。

研究方法

本研究会分辨和定义康养旅游的组成元素(以及其他在传统定义上被排除的行业), 透过重新审视和分析近20年有关于康养旅游(Wellness tourism)和健康旅游(Wellbeing tourism)的现存文献。同时, 所有元素会以开放式译码 (open coding)来分类。

成果

康养旅游, 作为一个多元概念, 基本上与十个不同的供应行业相关:温泉, 水療, 医疗旅游, 身心护理, 饮食, 运动, 自然环境, 文化, 灵修和特办活动。不同类别的行业可以在代表市场上不同供需关系的同时, 也可以代表供应上可以有一种混合套餐供应。

研究建议

以全面的目光去看康养旅游可以为市场策略定下基础。目的地管理公司(DMO)和不同的公司经理应该在分辨服务需求的时候, 多采用新颖的标准, 摒弃只包括医疗的传统健康观念。为游客订立的价值主张(Value propositions)应以全面身心健康为主导, 以满足对康养(Wellness)和健康(Wellbeing)不断上升的需求; 亦应大力度地提升所有安康旅游工作人员与顾客的互动和参与。

El turismo de bienestar y los componentes de su sistema de oferta: una perspectiva holística

Propósito

Este artículo examina conceptualmente el fenómeno del turismo de bienestar desde una perspectiva holística y sistémica, centrándose en el sistema de oferta y los principales componentes necesarios para la puesta en escena de experiencias de bienestar. Este enfoque de bienestar integral dentro del sector turístico ha propiciado una ampliación del tipo de servicios y experiencias que integran las propuestas de valor que pueden contribuir positivamente al bienestar de las personas.

Diseño/metodología/enfoque

Este estudio identifica y define los componentes del turismo de bienestar (incluidos los sectores no asociados tradicionalmente con él), a través de una revisión y análisis de la literatura existente sobre “turismo de bienestar” de las dos últimas décadas; los componentes se han clasificado mediante un proceso de codificación abierto.

Conclusiones

El turismo de bienestar está compuesto conceptualmente por diez componentes diferentes de ofertas: aguas termales, spas, turismo sanitario, cuidado de cuerpo y mente, enogastronomía, deportes, naturaleza y medio ambiente, cultura, espiritualidad y eventos. Cada una de estas categorías puede representar una única oferta turística para segmentos de mercado específicos, pero también pueden ser uno de los varios componentes de una combinación integrada de productos turísticos.

Originalidad/valor

Esta concepción holística del bienestar sugiere que, en el contexto de los procesos de marketing estratégico, las DMO y los gerentes de negocio deben segmentar la demanda con criterios innovadores respecto a los tradicionales de salud y médicos. Además, deben formular propuestas de turismo orientado al bienestar, valorizando los componentes de la oferta capaces de interceptar la creciente demanda de bienestar e implicando a los distintos productores del sistema de oferta de wellness que operan en los destinos de bienestar

Content available
Book part
Publication date: 22 August 2019

Brett Lashua

Abstract

Details

Popular Music, Popular Myth and Cultural Heritage in Cleveland: The Moondog, The Buzzard, and the Battle for the Rock and Roll Hall of Fame
Type: Book
ISBN: 978-1-78769-156-8

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