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1 – 10 of over 18000
Article
Publication date: 8 September 2022

Xie Yidong, Sun Peiweni, Li Qiang, Fu Caozheng, AiHua Zhu, Jianwei Yang and Chaochao Ma

The CL60 steel wheels of metro vehicles running on a specific line need frequent reprofiling due to rapid wear. Considering this problem, a new material for metro wheels…

44

Abstract

Purpose

The CL60 steel wheels of metro vehicles running on a specific line need frequent reprofiling due to rapid wear. Considering this problem, a new material for metro wheels was designed. The friction and wear properties of the new material were studied, to reduce the wear rate and extend the service life of metro wheels.

Design/methodology/approach

Wheel specimens made of the two steel materials were tested using a GPM-60 wear tester under laboratory conditions. A field test was conducted on a specific metro line to track the wear in wheels made of the new material and CL60 steel wheels.

Findings

Under the laboratory conditions, the wear loss in the new material was 24.44% lower than that in CL60 steel. The field test revealed that compared to CL60 steel wheels, the new CL60 steel wheels showed a 19.42% decrease in tread wear on average. The field measurements for the wheels made of the new material are consistent with the results of laboratory simulation, suggesting relatively high wear resistance of the new material.

Practical implications

The results of the study can provide guidance on how to properly select steel material for metro wheels to avoid rapid wear and frequent reprofiling and reduce operating costs.

Originality/value

A new material for metro wheels was designed and developed by optimizing the content of Cr, Si, Mn, V and other elements. This material proved to have better wear resistance in both laboratory and field testing.

Details

Industrial Lubrication and Tribology, vol. 74 no. 10
Type: Research Article
ISSN: 0036-8792

Keywords

Article
Publication date: 5 May 2022

Lida Wang, Xian Rong and Lingling Mu

This study aims to investigate the basic public service level in the Beijing-Tianjin-Hebei region under the impact of COVID-19.

Abstract

Purpose

This study aims to investigate the basic public service level in the Beijing-Tianjin-Hebei region under the impact of COVID-19.

Design/methodology/approach

This study constructed a basic public service-level evaluation system from the five dimensions of education, culture, health, social security and infrastructure and environment, and measures the basic public service level in 13 cities in Beijing, Tianjin and Hebei using the entropy method. The spatial pattern and dynamic evolution of the public service level are analysed from the perspective of dynamic trends in time series and spatial distribution, along with the reasons for the evolution of spatial distribution.

Findings

(1) The basic public service level in the 13 cities is generally on the rise, but the trend is unstable. (2) The basic public service level in space shows a general trend of attenuation from northeast to southwest, with significant spatial imbalance and orientation. (3) The regional differences first increase and then decrease. (4) The inter-group mobility of different basic public service levels is low, and cities with lower initial levels find it difficult to achieve leapfrog development. Moreover, the health service level of the region is still at a low stage, which is not conducive to effectively preventing and controlling the epidemic.

Originality/value

From the perspective of this research, the spatial pattern and dynamic evolution of basic public service were adopted to analyse the coordinated development of the Beijing-Tianjin-Hebei region. Furthermore, this study discusses how to improve the basic public service level to ensure sustainable operation in the region under the impact of COVID-19.

Details

Engineering, Construction and Architectural Management, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 0969-9988

Keywords

Article
Publication date: 27 September 2021

AiHua Zhu, AiHua Zhu, Chaochao Ma, Jianwei Yang, Xin Hou, Hongxiao Li and Peiwen Sun

Considering that a meet between high-speed trains can generate aerodynamic loads, this study aims to investigate the effect of high-speed train meet on wheel wear at…

76

Abstract

Purpose

Considering that a meet between high-speed trains can generate aerodynamic loads, this study aims to investigate the effect of high-speed train meet on wheel wear at different speeds to provide a more accurate wheel wear model and a new idea for reducing wheel wear.

Design/methodology/approach

The train speed was set at 250, 300, 350 and 400 km/h separately, and a vehicle system dynamics model was constructed using the parameters of an actual high-speed train on a line. The aerodynamic forces arising from constant-speed train meet were then applied as additional excitation. Semi-Hertzian theory and Kalker’s simplified theory were used to solve the wheel/rail contact problems. The wheel wear was calculated using Archard wear model. The effect of train meet on wheel wear was analyzed for the whole train, different cars and different axles.

Findings

According to the results, all wheels show a wear increase in the case of one train meet, compared to the case of no train meet. At 250, 300, 350 and 400 km/h, the total wheel wear increases by 4.45%, 4.91%, 7.57% and 5.71%, respectively, over the entire operational period. The change in speed has a greater impact on wheel wear increase in the head and tail cars than in the middle car. Moreover, the average wear increase in front-axle wheels is 1.04–2.09 times that in rear-axle wheels on the same bogie.

Practical implications

The results will help to analyze wheel wear more accurately and provide theoretical guidance for wheel repair and maintenance from the perspective of high-speed train meet.

Originality/value

At present, there is a lot of focus on the impact of high-speed train meet on the dynamic performance of vehicles. However, little research is available on the influence of train meet on wheel wear. In this study, a vehicle dynamics model was constructed and the aerodynamic forces generated during high-speed train meet were applied as additional excitation. The effect of train meet on wheel wear was analyzed for the whole train, different cars and different axles. The proposed method can provide a more accurate basis for wear prediction and wheel repair.

Details

Industrial Lubrication and Tribology, vol. 73 no. 7
Type: Research Article
ISSN: 0036-8792

Keywords

Article
Publication date: 8 February 2016

Fang Wang, Yaoyao Peng, Hsiao Chieh Wang and Fan Yin

Ancient city walls are typical linear space elements of Beijing that represent the transformation of urban form over the past 800 years and have greatly influenced the…

Abstract

Purpose

Ancient city walls are typical linear space elements of Beijing that represent the transformation of urban form over the past 800 years and have greatly influenced the memory of the entire city. However, recently, most of the walls have been torn down in the process of fast urbanization and old city renewal. The purpose of this paper is to focus on people’s cognition and evaluation of urban memory during this pull-down-and-preserve process.

Design/methodology/approach

A sample of 380 participants was investigated on a number of issues using questionnaires, including memory case reminders (stability, variability, temporality), emotional bonding with memory case (identity, dependence, authenticity), and socio-demographic variables (age, education, life experience, length of residence). The urban memory cognition model and attitude evaluation value model which were based on Likert scale were used to process the collected data.

Findings

In the three aspects of memory case reminders, stability and temporary elements can be most cognized, whereas variability elements are more difficult due to their change over time. As for emotional bonding with memory case, people show a high level of identification with the walls; the walls’ memory being passed down could enhance people’s memory when mentioning Beijing. Further, higher education groups consider the walls’ authenticity to be most important and are unwilling to accept the outcome of walls-ruins parks; older adults have tolerant attitudes to the ruins parks.

Originality/value

This study could not only contribute to the excavation of urban memory, but also strengthen citizens’ sense of identity and cohesiveness, thus shaping the spirit and culture of the city. Some findings could provide applicable guidelines for urban heritage protection and contribute a new perspective on the interrelationship between people and their physical surroundings.

Details

International Journal of Tourism Cities, vol. 2 no. 1
Type: Research Article
ISSN: 2056-5607

Keywords

Article
Publication date: 20 February 2020

Jeff Hai-chi Loo

The persistent growth of ‘nativists’ in Hong Kong not only highlighted people's consideration over mainlandization, it also stimulates Beijing's nerve on national…

Abstract

Purpose

The persistent growth of ‘nativists’ in Hong Kong not only highlighted people's consideration over mainlandization, it also stimulates Beijing's nerve on national security. This paper adopts a critical perspective to explore the development of ‘Hong Kong Nationalism’ that emerged in 2015. It will show the development of ‘Hong Kong nationalism’ is a phenomenon compounded by the creation of critical academics, government exaggeration, and pro-Beijing media labeling. In fact, this phenomenon leads to the suppression of political space for critical opposition.

Design/methodology/approach

The interaction between Hong Kong Special Administrative Region (HKSAR) government, central government, critical academics, and pro-Beijing media will be used to adopt a conceptual framework to show how their interrelationship would derive tremendous impacts to the development of ‘Hong Kong Nationalism.’ It will further investigate some implications for the further political development in Hong Kong.

Findings

The development of ‘Hong Kong Nationalism’ illustrates the triangular relations between critical academic, HKSAR and the Beijing government, and pro-Beijing media. The critical academics create and imagine such ‘Hong Kong Nationalism’ with Hong Kong's political destiny that stimulates the nerve of Beijing and HKSAR on territorial integrity. The ‘imagined nationalism’ advocated by critical and opposition academics and advanced by the activists not only opened the Pandora's box that derives a Trojan horse scenario for the development of pan-democratic camp which affects the democracy movement tremendously.

Originality

This paper is the first academic paper to explore ‘Hong Kong Nationalism’ through analyzing the discourse advocated by critical academics. This paper can also fill in the gap from existing literature about social movement in Hong Kong as most of them ignored the influence of radical nativist movement.

Details

Asian Education and Development Studies, vol. 9 no. 4
Type: Research Article
ISSN: 2046-3162

Keywords

Article
Publication date: 29 August 2008

Liu Mengjie, Richard Reed and Hao Wu

The purpose of this paper is analyse to what extent the high price had led to low levels of housing affordability in the period 2002‐2006 in Beijing. Due to the importance…

1651

Abstract

Purpose

The purpose of this paper is analyse to what extent the high price had led to low levels of housing affordability in the period 2002‐2006 in Beijing. Due to the importance of housing for local residents and the crucial position that real estate market in the Chinese economy is currently in, research into the housing affordability issues is now essential. It is important to consider the social circumstances that are predominantly related to both the standard of living and the national economy in Beijing.

Design/methodology/approach

The housing price to income ratio (PIR) method and Housing Affordability Index (HAI) model are used to measure housing affordability in Beijing. Then, the reasons for the high housing prices in Beijing are discussed and government homeownership‐oriented policies to help citizen on housing issues are examined. Finally, future proposals which can contribute to ease the housing affordability problem are recommended.

Findings

The main findings in this research are that the PIR in the Beijing housing market (based on an average gross floor area of 60 m2) fluctuated between 6.69 and 9.12, respectively, between 2002 and 2006. Over the same period, the HAI was approximately 75 between 2002 and 2004, although decreasing sharply in 2005 (65.78) and 2006 (51.33). It appears that the Chinese government's new housing provision policies may be able to ease this affordability problem, especially with regards to the economic housing scheme.

Originality/value

China has experienced rapid growth in gross domestic product (GDP) with a substantial increase in house prices which have affected housing affordability for typical Beijing households. Since the housing reform in China commenced in 1998, Beijing residents, government officers and academics have been concerned about high housing prices in the city, which is considered beyond the buying capability of the ordinary residents. The results are designed to provide an insight into the level of housing affordability in Beijing and whether a trend exists.

Details

International Journal of Housing Markets and Analysis, vol. 1 no. 3
Type: Research Article
ISSN: 1753-8270

Keywords

Article
Publication date: 14 May 2019

Yu Liu, Bingjie Liu-Lastres, Qiuju Wang and Yao-Yi Fu

Beijing is becoming one of the top global destinations but the number of international tourists to the city has been declining recently. By analyzing inbound tourists…

Abstract

Purpose

Beijing is becoming one of the top global destinations but the number of international tourists to the city has been declining recently. By analyzing inbound tourists experience in Beijing and identifying the relationship between the destination attributes and satisfaction, the purpose of this paper is to provide important insights into city tourism research and city destination development.

Design/methodology/approach

This study used an online deductive approach and collected 1,254 reviews on TripAdvisor referencing major attractions in Beijing. This study used the Leximancer software to analyze the content of the reviews and to identify the underlying relationships.

Findings

The results showed that international tourists’ experience in Beijing can be reflected via five aspects: attractions, city, transportation, service and people. The results further indicated that the major concern of international tourists visiting Beijing related to the service quality on site.

Originality/value

This study explored inbound tourists experience in Beijing using an online deductive approach. Practical implications were provided with respect to improving international tourists experience in Beijing and enhancing their satisfaction and revisiting intentions.

Details

International Journal of Tourism Cities, vol. 5 no. 3
Type: Research Article
ISSN: 2056-5607

Keywords

Article
Publication date: 30 November 2018

AiHua Zhu, Si Yang, Qiang Li, JianWei Yang, Xi Li and YiDong Xie

The purpose of this paper is to study the wear evolution of metro wheels under the conditions of different track sequences, track composition and vehicle load and then to…

239

Abstract

Purpose

The purpose of this paper is to study the wear evolution of metro wheels under the conditions of different track sequences, track composition and vehicle load and then to predict wheel wear and to guide its maintenance.

Methodology

By using the SIMPACK and MATLAB software, numerical simulation analysis of metro wheel wear is carried out based on Hertz theory, the FASTSIM algorithm and the Archard model. First of all, the vehicle dynamics model is established to calculate the motion relationship and external forces of wheel-rail in the SIMPACK software. Then, the normal force of wheel-rail is solved based on Hertz theory, and the tangential force of wheel-rail is calculated based on the FASTSIM algorithm through the MATLAB software. Next, in the MATLAB software, the wheel wear is calculated based on the Archard model, and a new wheel profile is obtained. Finally, the new wheel profile is re-input into the vehicle system dynamics model in the SIMPACK software to carry out cyclic calculation of wear.

Findings

The results show that the setting order of different curves has an obvious influence on wear when the proportion of the straight track and the curve is fixed. With the increase in running mileage, the severe wear zone is shifted from tread to flange root under the condition of the sequence-type track, but the wheel wear distribution is basically stable for the unit-type track, and their wear growth rates become closer. In the tracks with different straight-curved ratio, the more proportion the curved tracks occupy, the closer the severe wear zone is shifted to flange root. At the same time, an increase in weight of the vehicle load will aggravate the wheel wear, but it will not change the distribution of wheel wear. Compared with the measured data of one city B type metro in China, the numerical simulation results of wheel wear are nearly the same with the measured data.

Practical implications

These results will be helpful for metro tracks planning and can predict the trend of wheel wear, which has significant importance for the vehicle to do the repair operation. At the same time, the security risks of the vehicle are decreased economically and effectively.

Originality/value

At present, many scholars have studied the influence of metro tracks on wheel wear, but mainly focused on a straight line or a certain radius curve and neglected the influence of track sequence and track composition. This study is the first to examine the influence of track sequence on metro wheel wear by comparing the sequence-type track and unit-type track. The results show that the track sequence has a great influence on the wear distribution. At the same time, the influence of track composition on wheel wear is studied by comparing different straight-curve ratio tracks; therefore, wheel wear can be predicted integrally under different track conditions.

Details

Industrial Lubrication and Tribology, vol. 71 no. 2
Type: Research Article
ISSN: 0036-8792

Keywords

Article
Publication date: 9 March 2010

Yongzhou Hou

Beijing and Shanghai have been the leading housing markets in urban China. In the late half of the 2000s, both metropolises experienced a pronounced process of housing…

4767

Abstract

Purpose

Beijing and Shanghai have been the leading housing markets in urban China. In the late half of the 2000s, both metropolises experienced a pronounced process of housing price appreciation. The purpose of this paper is to examine whether there exist housing price bubbles in the two largest cities in China.

Design/methodology/approach

The study is based on a combination of different quantitative indicators: a comparison of housing market prices with the rational expectation price, mortgage loans, and the ratios of price to income and to rent. Moreover, the statistical tool of control chart is introduced to quantify housing bubbles.

Findings

The study shows that Beijing appears to have been on the way of forming a housing price bubble between 2005 and 2008, and that there perhaps existed a housing bubble in Shanghai from 2003 to 2004. It appears that the housing market cycle in Beijing may be divided into three stages: the cycle peak stage (1991‐1997), the cycle trough stage (1998‐2003) and the second cycle peak stage (2004‐2008).

Originality/value

In an attempt to explain the possible existence of housing bubbles in Beijing and Shanghai, this paper uses an integrated strategy involved with such fundamentals as interest rates, rent, income and GDP. In particular, the control chart, based on per capita GDP, is introduced to identify a housing bubble.

Details

International Journal of Housing Markets and Analysis, vol. 3 no. 1
Type: Research Article
ISSN: 1753-8270

Keywords

Article
Publication date: 11 May 2010

Qiao Zhang and Ke Wang

The purpose of this paper is to assess the production risk for winter wheat producers in Beijing, China, particularly in its 13 districts.

288

Abstract

Purpose

The purpose of this paper is to assess the production risk for winter wheat producers in Beijing, China, particularly in its 13 districts.

Design/methodology/approach

A parametric approach is used to model wheat‐yield distribution for samples and the Kolmogorov‐Smirnov test is used to choose the most appropriate yield distribution. Parameters of the special yield distribution are estimated through the maximum likelihood estimation approach.

Findings

The Burr distribution is found to be the most appropriate parametric distribution to model winter wheat‐production risks for the districts of Beijing, except in the districts of Fengtai and Shunyi. Findings also show that the Johnson family distribution is the most appropriate model for these two districts (SB for the Fengtai District and SU for the Shunyi District). The wheat‐production loss ratios of the Beijing districts are between 6 and 15 percent, which is considered medium range in most regions. The highest production risks are located in the Western regions of Beijing (Mentougou and Fengtai) while the lowest production risk is located in the Southeastern region of Beijing (Daxing District).

Originality/value

To generate an objective yield trend and an accurate production risk assessment, linear moving average, instead of linear (or quadratic) regression, is used in this paper.

Details

China Agricultural Economic Review, vol. 2 no. 2
Type: Research Article
ISSN: 1756-137X

Keywords

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