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Article
Publication date: 13 February 2020

Gangling Hou, Yu Liu, Meng Li, Menghan Sun, Feng Sun, Xiuyun Zhu, Rong Pan and Dongyu Zhang

In recent years, a new type of double-layered containment structure of nuclear power plant has been built in China, named ACP1000 NNP. This paper aims to propose a new method to…

189

Abstract

Purpose

In recent years, a new type of double-layered containment structure of nuclear power plant has been built in China, named ACP1000 NNP. This paper aims to propose a new method to mitigate the seismic responses of this type of the structure.

Design/methodology/approach

The new base isolation structure (BIS)- tuned mass damper (TMD) structure was proposed and implemented only by modifying the connection between various components of NPPs, and the application of this concept design in ACP1000 was skillfully realized.

Findings

The new structure adopts the combination of structural form and function, adopts appropriate amplification of the seismic response of the secondary component, possesses advantages in explicit damping mechanism, good damping effect, robustness of seismic structures, simple implementation process, etc., and meets the special seismic safety requirements of the NPPs.

Originality/value

This seismic and hazard mitigation and BIS-TMD structure can avoid the risk of ACP1000 accidents caused by horizontal earthquakes.

Details

Engineering Computations, vol. 37 no. 6
Type: Research Article
ISSN: 0264-4401

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Article
Publication date: 6 September 2021

Xiuyun Zhu, Rong Pan, Jianbo Li and Gao Lin

In recent years, three-dimensional (3D) seismic base isolation system has been studied extensively. This paper aims to propose a new 3D combined isolation bearing (3D-CIB) to…

357

Abstract

Purpose

In recent years, three-dimensional (3D) seismic base isolation system has been studied extensively. This paper aims to propose a new 3D combined isolation bearing (3D-CIB) to mitigate the seismic response in both the horizontal and vertical directions.

Design/methodology/approach

The new 3D-CIB composed of laminated rubber bearing coupled with combined disk spring bearing (CDSB) was proposed. Comprehensive analysis of constitution and theoretical derivation for 3D-CIB were presented. The advantage of CDSB is that the constitution can be flexibly adjusted according to the requirements of the bearing capacity and vertical stiffness. Hence, four different combinations of CDSB were designed for the 3D-CIB and employed to isolate nuclear reactor building. A comparative study of the seismic response in terms of seismic action, acceleration floor response spectra (FRS), peak acceleration and relative displacement response was carried out.

Findings

3D-CIB can effectively reduce seismic action, FRS and peak acceleration response of the superstructure in both the horizontal and vertical directions. Overall, the horizontal isolation effectiveness of 3D-CIB was slightly influenced by vertical stiffness. The decrease in the vertical stiffness of the 3D-CIB can reduce the vertical FRS and shift the peak values to a lower frequency. The vertical peak acceleration decreased with a decrease in the vertical stiffness. The superstructure exhibited a rocking effect during the earthquake, and the decrease in the vertical stiffness may increase the rocking of the superstructure.

Originality/value

Although the advantage of 3D-CIB is that the vertical stiffness can be flexibly adjusted by different constitutions, the vertical stiffness should be designed by properly accounting for the balance between the isolation effectiveness and displacement response. This study of isolation effectiveness can provide the technical basis for the application of 3D-CIB into real engineering of nuclear power plants.

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Article
Publication date: 16 October 2018

Xiufeng Zhang, Jitao Dai, Xia Li, Huizi Li, Huiqun Fu, Guoxin Pan, Ning Zhang, Rong Yang and Jianguang Xu

This paper aims to develop a signal acquisition system of surface electromyography (sEMG) and use the characteristics of (sEMG) signal to interference action pattern.

357

Abstract

Purpose

This paper aims to develop a signal acquisition system of surface electromyography (sEMG) and use the characteristics of (sEMG) signal to interference action pattern.

Design/methodology/approach

This paper proposes a fusion method based on combining the coefficient of AR model and wavelet coefficient. It improves the recognition rate of the target action. To overcome the slow convergence speed and local optimum in standard BP network, the study presents a BP algorithm which combine with LM algorithm and PSO algorithm, and it improves the convergence speed and the recognition rate of the target action.

Findings

Experiments verify the effectiveness of the system from two aspects the target motion recognition rate and the corresponding reaction speed of the robotic system.

Originality/value

The study developed a signal acquisition system of sEMG and used the characteristics of (sEMG) signal to interference action pattern. The myoelectricity integral values are presented to determine the starting point and end point of target movement, which is more effective than using single sample point amplitude method.

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Article
Publication date: 20 March 2024

Heji Zhang, Dezhao Lu, Wei Pan, Xing Rong and Yongtao Zhang

The purpose of this study is to design a closed hydrostatic guideway has the ability to resist large-side load, pitch moments and yaw moments, has good stiffness and damping…

43

Abstract

Purpose

The purpose of this study is to design a closed hydrostatic guideway has the ability to resist large-side load, pitch moments and yaw moments, has good stiffness and damping characteristics, and provides certain beneficial guidance for the design of large-span closed hydrostatic guideway on the basis of providing a large vertical load bearing capacity.

Design/methodology/approach

The Reynolds’ equation and flow continuity equation are solved simultaneously by the finite difference method, and the perturbation method and the finite disturbance method is used for calculating the dynamic characteristics. The static and dynamic characteristics, including recess pressure, flow of lubricating oil, carrying capacity, pitch moment, yaw moment, dynamic stiffness and damping, are comprehensively analyzed.

Findings

The designed closed hydrostatic guideway has the ability to resist large lateral load, pitch moment and yaw moment and has good stiffness and damping characteristics, on the basis of being able to provide large vertical carrying capacity, which can meet the application requirements of heavy two-plate injection molding machine (TPIMM).

Originality/value

This paper researches static and dynamic characteristics of a large-span six-slider closed hydrostatic guideway used in heavy TPIMM, emphatically considering pitch moment and yaw moment. Some useful guidance is given for the design of large-span closed hydrostatic guideway.

Details

Industrial Lubrication and Tribology, vol. 76 no. 3
Type: Research Article
ISSN: 0036-8792

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Article
Publication date: 21 November 2023

Hua Pan and Rong Liu

On the one hand, this paper is to further understand the residents' differentiated power consumption behaviors and tap the residential family characteristics labels from the…

55

Abstract

Purpose

On the one hand, this paper is to further understand the residents' differentiated power consumption behaviors and tap the residential family characteristics labels from the perspective of electricity stability. On the other hand, this paper is to address the problem of lack of causal relationship in the existing research on the association analysis of residential electricity consumption behavior and basic information data.

Design/methodology/approach

First, the density-based spatial clustering of applications with noise method is used to extract the typical daily load curve of residents. Second, the degree of electricity consumption stability is described from three perspectives: daily minimum load rate, daily load rate and daily load fluctuation rate, and is evaluated comprehensively using the entropy weight method. Finally, residential customer labels are constructed from sociological characteristics, residential characteristics and energy use attitudes, and the enhanced FP-growth algorithm is employed to investigate any potential links between each factor and the stability of electricity consumption.

Findings

Compared with the original FP-growth algorithm, the improved algorithm can realize the excavation of rules containing specific attribute labels, which improves the excavation efficiency. In terms of factors influencing electricity stability, characteristics such as a large number of family members, being well employed, having children in the household and newer dwelling labels may all lead to poorer electricity stability, but residents' attitudes toward energy use and dwelling type are not significantly associated with electricity stability.

Originality/value

This paper aims to uncover household socioeconomic traits that influence the stability of home electricity use and to shed light on the intricate connections between them. Firstly, in this article, from the perspective of electricity stability, the characteristics of the power consumption of residents' users are refined. And the authors use the entropy weight method to comprehensively evaluate the stability of electricity usage. Secondly, the labels of residential users' household characteristics are screened and organized. Finally, the improved FP-growth algorithm is used to mine the residential household characteristic labels that are strongly associated with electricity consumption stability.

Highlights

  1. The stability of electricity consumption is important to the stable operation of the grid.

  2. An improved FP-growth algorithm is employed to explore the influencing factors.

  3. The improved algorithm enables the mining of rules containing specific attribute labels.

  4. Residents' attitudes toward energy use are largely unrelated to the stability of electricity use.

The stability of electricity consumption is important to the stable operation of the grid.

An improved FP-growth algorithm is employed to explore the influencing factors.

The improved algorithm enables the mining of rules containing specific attribute labels.

Residents' attitudes toward energy use are largely unrelated to the stability of electricity use.

Details

Management of Environmental Quality: An International Journal, vol. 35 no. 3
Type: Research Article
ISSN: 1477-7835

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Article
Publication date: 21 October 2022

Ying Zhang, Shiyu Rong, Elizabeth Dunlop, Rong Jiang, Zhenyong Zhang and Jun Qing Tang

The purpose of this paper is to explore the longitudinal influence of gender, age, education level, organizational tenure and emotional intelligence on three dimensions of…

964

Abstract

Purpose

The purpose of this paper is to explore the longitudinal influence of gender, age, education level, organizational tenure and emotional intelligence on three dimensions of knowledge hiding over time.

Design/methodology/approach

A longitudinal study using two-wave data sets of 390 employees in Chinese enterprises was conducted to build fixed, continuous and interacting models for investigating the effects of individual differences on the processes of knowledge hiding over time.

Findings

This research uncovered the changing relationships of individual differences on knowledge-hiding behaviors over time, such that age correlates with rationalized hiding in the interacting model, indicating younger employees are less likely to choose rationalized hiding when facing situation changes; and education level, organizational tenure and emotional intelligence moderate knowledge hiding over time, implying individuals with better education, longer tenure and higher emotional intelligence tend to exhibit more rationalized hiding behaviors rather than evasive hiding and playing dumb behaviors at Time 2.

Originality/value

One of the novel contributions of this study is that it tests the longitudinal effect of individual differences on knowledge hiding, providing a vertical perspective, and thereby contributing to the body of knowledge in knowledge management. The study also constructs fixed, continuous and interacting models to measure the covering longitudinal influences, thus making the research original.

Details

Journal of Knowledge Management, vol. 27 no. 6
Type: Research Article
ISSN: 1367-3270

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Article
Publication date: 5 June 2019

Gangling Hou, Meng Li, Sun Hai, Tianshu Song, Lingshu Wu, Yong Li, Gang Zheng, Feng Shen and Yaodong Chen

Seismic isolation, as an effective risk mitigation strategy of building/bridge structures, is incorporated into AP1000 nuclear power plants (NPPs) to alleviate the seismic damage…

266

Abstract

Purpose

Seismic isolation, as an effective risk mitigation strategy of building/bridge structures, is incorporated into AP1000 nuclear power plants (NPPs) to alleviate the seismic damage that may occur to traditional structures of NPPs during their service. This is to promote the passive safety concept in the structural design of AP1000 NPPs against earthquakes.

Design/methodology/approach

In conjunction with seismic isolation, tuned-mass-damping (TMD) is integrated into the seismic resistance system of AP1000 NPPs to satisfy the multi-functional purposes. The proposed base-isolation-tuned-mass-damper (BIS-TMD) is studied by comparing the seismic performance of NPPs with four different design configurations (i.e. without BIS, BIS, BIS-TMD and TMD) with the design parameters of the TMD subsystem optimized.

Findings

Such a new seismic protection system (BIS-TMD) is proved to be promising because the advantages of BIS and TMD can be fully used. The benefits of the new structure include effective energy dissipation (i.e. wide vibration absorption band and a stable damping effect), which results in the high performance of NPPs subject to earthquakes with various intensity levels and spectra features.

Originality/value

Parametric studies are performed to demonstrate the seismic robustness (e.g. consistent performance against the changing mass of the water in the gravity liquid tank and mechanical properties) which further ensures that seismic safety requirements of NPPs can be satisfied through the use of BIS-TMD.

Details

Engineering Computations, vol. 36 no. 4
Type: Research Article
ISSN: 0264-4401

Keywords

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Article
Publication date: 2 February 2015

C. K. Mukhopadhyay, T.K. Haneef, T. Jayakumar, G.K. Sharma and B.P.C. Rao

The purpose of this paper is to present the results of acoustic emission (AE) and ultrasonic inspection of two H2S storage tanks carried out in a heavy water plant, in order to…

214

Abstract

Purpose

The purpose of this paper is to present the results of acoustic emission (AE) and ultrasonic inspection of two H2S storage tanks carried out in a heavy water plant, in order to characterize point type defects observed during earlier ultrasonic inspection and to ensure that these defects are not growing during hydrotesting of the tanks.

Design/methodology/approach

Using multiple AE sensors and AE source location methodology, the entire tank could be covered to detect and locate any dynamic sources of AE associated with local plastic deformation and/or growing discontinuities from any part of the tank during the hydrotest. For confirmation of the results obtained by AE, ultrasonic inspection on the tanks and on virgin plates from which the tanks were manufactured, were carried out.

Findings

The AE signals generated during first pressurisation are attributed to the micro yielding of the material of the tanks. A few scattered AE events were observed at a few locations during the hydrotesting of the tanks and these are due to structural and rubbing noise. During hold periods and repressurising cycle of the hydrotesting, no detectable AE events were observed and this confirmed the absence of any growing discontinuity in the tanks during the hydrotesting. Ultrasonic inspection on the tanks and on virgin plates confirmed that the point type defects detected are manufacturing defects and not formed during service life.

Practical implications

The combined results from AE and ultrasonic techniques confirmed the structural integrity of the tanks and ensured their healthiness for continued operation.

Originality/value

The paper brings out the use of AE and ultrasonic techniques for monitoring hydrotesting of storage tanks of a heavy water plant. The storage tanks where point type defect indications were reported during previous ultrasonic inspection and whether these defects are growing during hydrotesting of the tanks or not, were required to be known before the tanks are put in to further service. AE signals collected during pressurising and repressurising cycles of the hydrotest and subsequent inspection by ultrasonic confirmed the vessels to be free from growing defects during the hydrotest and provided baseline data for future inspection.

Details

International Journal of Structural Integrity, vol. 6 no. 1
Type: Research Article
ISSN: 1757-9864

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Article
Publication date: 1 May 1999

Zhang Lihong and Keith Goffin

International joint venture (IJV) manufacturing is important for both the Chinese economy and a large number of foreign investors. A review of the literature from both Western and…

4953

Abstract

International joint venture (IJV) manufacturing is important for both the Chinese economy and a large number of foreign investors. A review of the literature from both Western and Chinese researchers showed that although the purpose and advantages of IJV manufacturing in China are known, a vital aspect – operations management – has largely been ignored. Therefore, exploratory interviews with managers at six companies were conducted to investigate the operations management issues faced by IJV manufacturers in China. Four main problems were identified: the difficulty with recruiting and training suitable employees; all aspects of supplier management; problems with achieving high‐quality output; and achieving an effective IJV business culture. The results have implications not only for researchers, in that they indicate where more research is necessary, but also for practitioners, since they identify the areas where IJV manufacturers are most likely to encounter problems in China.

Details

International Journal of Operations & Production Management, vol. 19 no. 5/6
Type: Research Article
ISSN: 0144-3577

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Article
Publication date: 1 January 1999

Kwong‐leung Tang

Examines the extent to which social policy adopted by the colonial government in Hong Kong (prior to its hand‐over China in 1997) has set the agenda for the government of the…

1181

Abstract

Examines the extent to which social policy adopted by the colonial government in Hong Kong (prior to its hand‐over China in 1997) has set the agenda for the government of the newly formed Special Administrative Region (SAR). Chronicles the historical development of social policy in Hong Kong since the inception of the colonial government in 1842; identifies that, with the exception of a short‐lived period of expansionism (stimulated by social unrest in the mid‐1960’s) social welfare provision appears to have been low on the government’s agenda and incremental in nature ‐ the emphasis being on economic growth, rather than public spending on welfare programmes. Examines the strengths and weaknesses of this incremental approach; outlines the commitment of the SAR government to the market economy and its proposals for a modest increase in welfare provision, essentially building on the legacy left behind by the colonial government.

Details

International Journal of Sociology and Social Policy, vol. 19 no. 1/2
Type: Research Article
ISSN: 0144-333X

Keywords

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