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Article
Publication date: 9 February 2015

Gao Gengyuan, Yin Zhongwei, Jiang Dan and Zhang Xiuli

The purpose of this paper is to improve hydrodynamic load-carrying capacity of a water-lubricated journal bearing by a new bush structure. Water-lubricated bearing is…

Abstract

Purpose

The purpose of this paper is to improve hydrodynamic load-carrying capacity of a water-lubricated journal bearing by a new bush structure. Water-lubricated bearing is becoming more and more popular since it is environmentally friendly and saves energy. However, contrary to oil and grease-lubricated bearings, water-lubricated bearing is limited in many situations due to its low hydrodynamic load-carrying capacity.

Design/methodology/approach

The present article proposes a new bearing bush, with a transition-arc structure, which is favorable for increasing hydrodynamic load-carrying capacity. Hydrodynamic load-carrying capacity was calculated by means of three-dimensional computational fluid dynamics (3-D CFD) analysis. Several variants of a journal bearing with a transition-arc structure of different dimensions are analyzed, while the radial clearance of the bearing, eccentricity ratio and the velocity of the journal remain unchanged.

Findings

The results show that obvious changes are found in hydrodynamic load-carrying capacity of a water-lubricated journal bearing. For different width over diameter (L/D) bearing ratios, the relationship between hydrodynamic load-carrying capacity and the magnitude of the transition-arc structure dimension is researched.

Originality/value

The research presented here leads to a design reference guideline that could be used by the designer engineer to design smart journal bearings for improving the hydrodynamic load-carrying capacity.

Details

Industrial Lubrication and Tribology, vol. 67 no. 1
Type: Research Article
ISSN: 0036-8792

Keywords

Article
Publication date: 8 January 2018

Xiao-dong Yu, Lei Geng, Xiao-jun Zheng, Zi-xuan Wang and Xiao-gang Wu

Rotational speed and load-carrying capacity are two mutual coupling factors which affect high precision and stable operation of a hydrostatic thrust bearing. The purpose…

Abstract

Purpose

Rotational speed and load-carrying capacity are two mutual coupling factors which affect high precision and stable operation of a hydrostatic thrust bearing. The purpose of this paper is to study reasonable matching relationship between the rotational speed and the load-carrying capacity.

Design/methodology/approach

A mathematical model of relationship between the rotational speed and the load-carrying capacity of the hydrostatic bearing with double-rectangle recess is set up on the basis of the tribology theory and the lubrication theory, and the load and rotational speed characteristics of an oil film temperature field and a pressure field in the hydrostatic bearing are analyzed, reasonable matching relationship between the rotational speed and the load-carrying capacity is deduced and a verification experiment is conducted.

Findings

By increasing the rotational speed, the oil film temperature increases, the average pressure decreases and the load-carrying capacity decreases. By increasing the load-carrying capacity, the oil film temperature and the average pressure increases and the rotational speed decreases; corresponding certain reasonable matching values are available.

Originality/value

The load-carrying capacity can be increased and the rotational speed improved by means of reducing the friction area of the oil recess by using low-viscosity lubricating oil and adding more oil film clearance; but, the stiffness of the hydrostatic bearing decreases.

Article
Publication date: 17 May 2018

Vanessa Muler Gonzalez, Lluis Coromina and Nuria Galí

This paper aims to assess the value of impact perceptions as an indicator of social carrying capacity in the heritage town of Besalú, Spain. Additionally, it assesses the…

10310

Abstract

Purpose

This paper aims to assess the value of impact perceptions as an indicator of social carrying capacity in the heritage town of Besalú, Spain. Additionally, it assesses the impact tourism dependence and other socio-demographic variables have on this indicator.

Design/methodology/approach

A literature review on social exchange theory (SET) and carrying capacity related to impact perceptions is presented. The method was a survey, with a questionnaire based on the literature review and in-depth interviews. The results have been analyzed statistically to determine the links between perceptions and socio-demographic variables. Using statistical tools, perceptions are compared to three indicators that have been used to determine capacity in literature: willingness to accept more tourism, tourism pressure and the tourist function index.

Findings

The willingness of residents to enter into, and remain, in an exchange relationship is affected primarily by tourism dependence, and to a lesser extent by gender and education. Additionally, impact perceptions do not correspond to a willingness to accept more tourists. The impacts of tourism on conservation show greater consensus, while impacts on the availability of space for residents show links to other capacity indicators.

Originality/value

This study enhances the body of knowledge on social carrying capacity in heritage towns, by focusing on a regionally prominent day-tripper heritage town facing high tourism pressure which is Besalú. From a theoretical perspective, this study attempts to merge carrying capacity and SET, thus linking sustainability to social exchange. It also highlights the importance of a gender-based perspective in sustainability.

Details

Tourism Review, vol. 73 no. 3
Type: Research Article
ISSN: 1660-5373

Keywords

Article
Publication date: 7 October 2013

Ludwik Kania and Marek Krynke

The purpose of this paper is to discuss the calculation problem of the real carrying capacity of slewing bearings. The selection of slewing bearing to heavy-duty machine…

Abstract

Purpose

The purpose of this paper is to discuss the calculation problem of the real carrying capacity of slewing bearings. The selection of slewing bearing to heavy-duty machine according to catalogue carrying capacity and also according to locally determined real carrying capacity is insufficient and it can be the cause of the damage of machine during exploitation.

Design/methodology/approach

The concepts of the local, total and general capacities is defined. The general capacity is a logical product of the local capacities. It is particularly useful in an analysis of slewing bearings incorporated into machines with complex structures. The FEM is applied in computations. The formation method of the mathematical model of a bearing is presented.

Findings

The computations of the local capacities and general capacity of a bearing for the limiting load of the bearing traces and the limiting tension of the bolts fastening the bearing were carried out. Considerations were illustrated by an example of the bearing of a mobile crane.

Practical implications

The paper presented in the methodology of the calculation of general bearing carrying capacity and the obtained results of calculations can be used already by designers of bearings and machine engines to elimination of the potential damages of machine on the stage of projecting.

Originality/value

The general capacity of a bearing into machines with complex and irregulars structure is considerably lower than the bearing catalogue capacity and then the local teal capacity. The reasons for the differences between the catalogue capacity and the general capacity of slewing bearings were given.

Details

Engineering Computations, vol. 30 no. 7
Type: Research Article
ISSN: 0264-4401

Keywords

Abstract

Details

The Overtourism Debate
Type: Book
ISBN: 978-1-83867-487-8

Book part
Publication date: 13 May 2021

Nurhayat Iflazoglu and Ipek Itir Can

While the number of tourists worldwide is expected to reach 1.8 billion people by 2030, tourism destinations try to meet demand for increasing tourism. However, some…

Abstract

While the number of tourists worldwide is expected to reach 1.8 billion people by 2030, tourism destinations try to meet demand for increasing tourism. However, some tourism destinations are experiencing a maturity period of destination life cycle intensively. During these mature periods, while they meet the demand above their tourism carrying capacity, they encounter some problematic issues. In tourist destinations such as Venice, Barcelona and Paris, the negative feelings developed by the local people towards overtourism or tourists result in serious problems like negative destination images, tourism phobia, etc. In these destinations, to prevent the negative consequences of overtourism, destination stakeholders should develop solutions to these problems. There are many solution techniques for the problems which cause overtourism. One of them is the different tourism types which have been developed as an alternative to mass tourism. These alternative tourism types can be handled as a method for solving problems revealed through excess demand in tourism destinations at risk. For example, some tourism destinations which have both beach tourism and nature-based tourism types can bring nature-based tourism activities to the forefront with promotion and marketing activities and therefore, the tourism demand could be balanced between these tourism types. In this context, firstly, comprehensive literature review of overtourism and alternative tourism will be conducted in this study. And then the different types of tourism such as ecotourism, cultural tourism and responsible tourism will be discussed in detail and their relation in reducing the negative consequences of overtourism will be investigated theoretically via secondary data. Therefore, alternative tourism potentials will be investigated and tried to present the managerial suggestions for the development of different alternative types of tourism. As a result, it has been seen that, alternative tourism not only contributes to the growth of tourism in both popular and remote destinations but also makes sure that destinations get their fair share in income distribution of the country.

Article
Publication date: 16 November 2015

Adilson Aderito da Silva, Dimária Silva e Meirelles and Elvio Correa Porto

The purpose of this paper is to examine the development cycle of Brazilian banking sector during the lengthy period between 1889 and 2009, also identifying an equilibrium…

194

Abstract

Purpose

The purpose of this paper is to examine the development cycle of Brazilian banking sector during the lengthy period between 1889 and 2009, also identifying an equilibrium number of financial institutions based on the carrying capacity of the environment.

Design/methodology/approach

The number of institutions in equilibrium is calculated based on the population density dependence model adopted under the organizational ecology theory. Quantitative data of founding and failure and qualitative data (interviews with the directors, officers and chief executive officers (CEOs) of selected companies) were used.

Findings

In all three bank segments (commercial, investment and multiple), the total number of banks in operation on December 31, 2009 was below the carrying capacity. However, in the multiple bank segment, the gap between the actual and potential figures is slightly smaller. As indicated by the respondents, there is almost no room for newcomers in the major bank segments. In counterpart, there is still space for new arrivals in the mid-market bank sector.

Research limitations/implications

The findings presented here may change, as carrying capacity is determined by political, legal and economic factors, including the availability of resources in niches and constraints imposed through laws, rules and other regulatory aspects. However, raising the life cycle of the entire population offers opportunities for future research on individual organizational trajectories, using new theoretical and methodological perspectives, such as dynamic capabilities and process theory.

Practical implications

The main contribution of this paper lies in indicating the growth potential for banking institution populations in Brazil, and may be used not only by potential newcomers eager to enter the sector, but also as a tool for assessing anti-trust policies.

Originality/value

The development cycle of Brazilian financial institution populations is unknown, and carrying capacity is a construct less explored by academic literature, particularly in Brazil. This is a unique study since a demography of an entire banking population in a developing country does not exist, besides there is not such a financial institution like the multiple bank in Brazil.

Details

Management Research: The Journal of the Iberoamerican Academy of Management, vol. 13 no. 3
Type: Research Article
ISSN: 1536-5433

Keywords

Article
Publication date: 12 June 2017

Leonardo (Don) A.N. Dioko and Amy S.I. So

The purpose of this study is to propose a destination-level framework incorporating subjective and overall assessments of residents’ quality of life (QOL) and visitors…

Abstract

Purpose

The purpose of this study is to propose a destination-level framework incorporating subjective and overall assessments of residents’ quality of life (QOL) and visitors’ quality of experience (QOE) as a means for managing optimum levels of visitor volume at destinations.

Design

The proposed framework is empirically tested and applied using a large-scale survey of residents and visitors across a four-year time span in Macao, a Special Administrative Region of China that counts among the smallest and densest city-states in the world and which has borne the full force of extraordinary rapid tourism growth in recent years.

Findings

The study’s findings suggest that subjective assessments of residents’ QOL and visitors’ QOE interact and must be considered together when assessing sustainable levels of tourism at the level of a destination.

Originality

The study’s value lies in its use of a large-scale survey across a four-year time span to empirically validate theorized maximal values of QOL assessments from the point of view of residents as well as quality of visiting experience from the point of view of visitors. This finding lays future groundwork for more robust management of tourism growth in destinations.

Details

Worldwide Hospitality and Tourism Themes, vol. 9 no. 3
Type: Research Article
ISSN: 1755-4217

Keywords

Article
Publication date: 3 July 2018

Małgorzata Świąder

Uncontrolled and unsustainable urban development has a significant impact on the overall quality of the environment. Contemporary spatial management does not take into…

Abstract

Purpose

Uncontrolled and unsustainable urban development has a significant impact on the overall quality of the environment. Contemporary spatial management does not take into account the non-economic conditions of ecosystem functions and their biophysical limits, which results in a deterioration of the environment. Furthermore, urban development continues all over the world, which is associated with a projected population increase, particularly in cities. Therefore, there is need to include analyses in the field of environmental carrying capacity (ECC) for more sustainable spatial management and development. The ECC concept is a tool for sustainable development of human settlements. It could be defined as threshold level of anthropopressure, which the environment is able to balance and withstand without serious degradation and irreversible changes. The use of ECC assessment will help ensure the needs of the city’s residents, which are conditioned by the environment. The paper aims to discuss this issue.

Design/methodology/approach

This review study presents an overview of the ECC concept and its potential for use in spatial management at local level, especially for cities. The content analysis introduces definitions of spatial management and others main actions of spatial economy as well as the definitions of ECC. The overview of existing ECC models is a part of presented review.

Findings

The paper shows the ECC approach from global to local level on Poland as an example country.

Originality/value

The literature review identified that the idea of ECC could be a useful concept and tool for sustainable spatial development and management. This concept allows for verification of the resources and environmental state of given territory unit. Therefore, the assessment of ECC allows to verify if development of given area, for instance country, region or even city, is conducted within the framework of sustainable principles. Despite this, the assessment of ECC is not taken into account when future spatial management is defined. Thus, this circumstance could be a reason for this research area development.

Details

Management of Environmental Quality: An International Journal, vol. 29 no. 6
Type: Research Article
ISSN: 1477-7835

Keywords

Article
Publication date: 17 August 2010

Paresh Indubhai Andharia and Gunamani Deheri

The paper aims to improve upon the performance of a squeeze film formed by a magnetic fluid between longitudinally rough conical plates.

Abstract

Purpose

The paper aims to improve upon the performance of a squeeze film formed by a magnetic fluid between longitudinally rough conical plates.

Design/methodology/approach

The objectives are achieved by mathematically modeling a magnetic fluid‐based squeeze film between longitudinally rough conical plates. The roughness of the bearing surface is modeled by a stochastic random variable with non‐zero mean, variance and skewness. The standard approach is to solve associated Reynold's equation which is stochastically averaged with respect to the random roughness parameter. The scope of this paper is the industrial applications with regard to enhanced performance of the bearing system.

Findings

The findings indicate that the performance of the bearing gets enhanced due to negatively skewed roughness. It is also noticed that the standard deviation increases the load carrying capacity which is unlike the case of transverse surface roughness. Further, this paper suggests that there exist considerable scopes for enhancing the performance of the longitudinally rough bearing system by choosing a suitable combination of the magnetization parameter and the semi‐vertical angle of the cone.

Practical implications

From the industry point of view, this investigation will be certainly useful for improving the performance of a magnetic fluid‐based squeeze film between longitudinally rough conical plates.

Originality/value

The paper presents the improved performance of a squeeze film formed by a magnetic fluid between longitudinally rough conical plates and thereby extending the life period of the bearing system.

Details

Industrial Lubrication and Tribology, vol. 62 no. 5
Type: Research Article
ISSN: 0036-8792

Keywords

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