Xintian Liu, Jiazhi Liu, Haijie Wang and Xiaobing Yang
To improve the accuracy of parameter prediction for small-sample data, considering the existence of error in samples, the error circle is introduced to analyze original samples.
Abstract
Purpose
To improve the accuracy of parameter prediction for small-sample data, considering the existence of error in samples, the error circle is introduced to analyze original samples.
Design/methodology/approach
The influence of surface roughness on fatigue life is discussed. The error circle can treat the original samples and extend the single sample, which reduces the influence of the sample error.
Findings
The S-N curve obtained by the error circle method is more reliable; the S-N curve of the Bootstrap method is more reliable than that of the Maximum Likelihood Estimation (MLE) method.
Originality/value
The parameter distribution and characteristics are statistically obtained based on the surface roughness, surface roughness factor and intercept constant. The original sample is studied by an error circle and discussed using the Bootstrap and MLE methods to obtain corresponding S-N curves. It provides a more trustworthy basis for predicting the useful life of products.
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Jiazhi Lei, Qingwu Gong and Jun Ye
This paper aims to propose a simplified model of vanadium redox flow batteries (VRBs) for VRB energy storage system (ESS) design considering the operational characteristics of…
Abstract
Purpose
This paper aims to propose a simplified model of vanadium redox flow batteries (VRBs) for VRB energy storage system (ESS) design considering the operational characteristics of VRB, and a VRB ESS, considering the low terminal voltage of VRB, was presented.
Design/methodology/approach
According to the designed topology of VRB ESS and the simplified model of VRB, a small perturbation analysis method was used to establish the transfer function of VRB ESS, and the controller parameters of VRB ESS under constant charging and discharging current were designed.
Findings
Test results have demonstrated that this designed VRB ESS has fast response, small overshoot, strong adaptation and high steady precision, which strongly verified the reasonable design.
Practical implications
This simplified model of VRB can be suitably used for VRB ESS design. This designed VRB ESS realized the bidirectional power flow of VRB and AC grid. In this designed VRB ESS, phase-shifted full-bridge converter and a single-phase inverter were used and VRB was charged and discharged under constant current.
Originality/value
The paper presents a topology of VRB ESS which can realize the bidirectional power flow of VRB and AC grid. Considering the complexity of VRB model, a simplified model of VRB was proposed for the controller parameters design of VRB ESS, and this method can be used in application.
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Jiazhi Miao, Yongqing Li, Xiang Rao, Libao Zhu, Zhiwei Guo and Chengqing Yuan
The emission from marine engines has a crucial effect on energy economy and environment pollution. One of the effective emission reduction schemes is to minimize the friction loss…
Abstract
Purpose
The emission from marine engines has a crucial effect on energy economy and environment pollution. One of the effective emission reduction schemes is to minimize the friction loss of main friction pairs such as cylinder liner-piston ring (CLPR). Micro-groove textures were designed to accomplish this aim.
Design/methodology/approach
The authors experimentally investigated the effects of micro-groove textures at different cylinder liner positions. The micro-groove texture was fabricated on samples by chemical etching and cut from the real CLPR pair. Sliding contact tests were conducted by a reciprocation test apparatus.
Findings
The average friction coefficient of grooves at 30° inclination were reduced up to 58.22% and produced better tribological behavior at most conditions. The operating condition was the critical factor that determined the optimum texture pattern. The surface morphology indicated that textures could produce smoother surfaces and less scratches as compared with the untextured surface.
Originality/value
Inclined grooves and V-grooves were designed and applied to real CLPR pairs. The knowledge obtained in this study will lead to practical basis for tribological design and manufacturing of CLPR pair in marine diesel engines.
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Feng Zhao, Jianbao Zhang and Zhen Luo
The correlations and deviations between market prices, production prices and values are critical indexes for testing the labor theory of value. However, there is not yet a…
Abstract
Purpose
The correlations and deviations between market prices, production prices and values are critical indexes for testing the labor theory of value. However, there is not yet a universally accepted method of solving for the production price vector, and given the complexity and volatility of economic dynamics, production prices based on the assumption of economic equilibrium cannot be accurate measuring. This paper attempts to propose a new approach to test the labor theory of value.
Design/methodology/approach
This paper proposes a different approach. From the perspective of disequilibrium price, the paper deduces that the range of the relative prices of commodities is determined by the relative value, the rate of surplus-value and the technical structure of production inputs, with relative price fluctuating within the value range specified by the labor theory of value under market competition influences.
Findings
With empirical research results based on China’s economic data, this paper not only affirms the scientific and practical explanatory power of the labor theory of value in a more general sense but also uncovers how surplus value is distributed across sectors, which can be used to analyze market competition and technical relations and their impacts on industrial structure and distribution.
Originality/value
The disequilibrium analytical framework provides a new perspective for the empirical study of labor theory of value. Moreover, it evolves the labor theory of value into a robust empirical framework, breaking through the theoretical path of the traditional labor theory of value that is mostly limited to the normative discussion of exploitation.
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Guocheng Xiang, Jingjing Liu and Yuxuan Yang
The modernization of China’s economy is an integral part of Chinese-style modernization. According to the principle of unifying…
Abstract
Purpose
The modernization of China’s economy is an integral part of Chinese-style modernization. According to the principle of unifying theoretical, historical and practical logic, theoretically explaining the modernization of China’s economy is both a political necessity and a higher scientific requirement.
Design/methodology/approach
Following this evolutionary line – from modes of production to the general economic development mechanism and then to patterns of economic operation and development – this paper employs the principal contradiction analysis method to offer an interpretation of China’s economic modernization from the broad Marxist political economy perspective.
Findings
In economic terms, “get organized” primarily refers to the development and mutual promotion of team-based and market-based division of labor organizations, as discussed by Karl Marx. “Get organized” (specifically the development of team-based division of labor organizations) acts as the engine of China’s economic modernization and serves as the historical logical starting point. Division of labor is the theoretical logical starting point for interpreting China’s economic modernization. The two of them are congruent, achieving the unity of theoretical and historical logic at the starting point. The development and mutual promotion of these “two types of division of labor” inherently generate the general mechanism of economic development first comprehensively discussed by Marx and Friedrich Engels, which involves the division of labor development and market expansion accumulating cyclically and reinforcing each other. This mechanism drives both the high-speed and high-quality development of China’s economic modernization.
Originality/value
The broad Marxist political economy paradigm facilitates explaining China’s economic modernization theoretically, historically and practically with unified logic. “Get organized” serves as both the engine and the realization mechanism of this modernization, with the Communist Party of China (CPC) consistently being the core force of this organizational effort.
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This paper analyses the escalating Sino-Western race to develop a safe, efficacious and durable vaccine (i.e. “Goldilocks COVID-19 vaccine”). It argues that such efforts would be…
Abstract
Purpose
This paper analyses the escalating Sino-Western race to develop a safe, efficacious and durable vaccine (i.e. “Goldilocks COVID-19 vaccine”). It argues that such efforts would be considerably more effective if there is greater international cooperation instead of the corrosive rivalry driven by misplaced nationalism.
Design/methodology/approach
This study deploys a case-study approach, supported by literature on existing coronavirus disease 2019 (COVID-19) vaccine development efforts.
Findings
Despite the seeming success of recent COVID-19 vaccines, their actual efficacy is far from certain. Moreover, access to these vaccines would not be equitable internationally. This problem is exacerbated by the fact that their unique properties make storage and distribution prohibitively expensive, and international mechanisms to provide distribution to economically depressed regions are non-existent. Given the significant difficulties, it would be incumbent upon the great powers (i.e. China and America) to work together not only in vaccine development but also in the establishment of a distribution platform to ensure equitable access worldwide.
Originality/value
This study is one of the few social science research papers on COVID-19 vaccine development and its implications for society at large.
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Social entrepreneurship, leveraging economic activities to achieve social benefits, offers women the opportunity to freely and actively shape the contours of their work in…
Abstract
Purpose
Social entrepreneurship, leveraging economic activities to achieve social benefits, offers women the opportunity to freely and actively shape the contours of their work in meaningful ways. This study aims to examine how Chinese women use job crafting in social entrepreneurship to align their gender identity, forge meaningful work and new relationships and navigate mixed gender expectations.
Design/methodology/approach
The study is based on 19 in-depth interviews with young women engaging in social entrepreneurship in China. Using a grounded theory approach, the study explores how women craft their gender identity into the unconventional career path of creating their social venture, focusing on the creative combination of task, relational and cognitive crafting in shaping social entrepreneurship.
Findings
The findings suggest that women make social entrepreneurship meaningful by actively aligning their gender experiences to delineate a relational and cognitive causal path between their social enterprise, their identity as women and their moral values. By working for a larger social cause, women may cognitively reframe their gender identity to compromise financial performance for social impact.
Originality/value
Current studies on social entrepreneurship in China have yet to examine its development through a gender lens. This study uses job crafting to highlight the distinctive gender meaning-making process for Chinese women to enhance their work identity and to challenge normative gender expectations. The study shows that job crafting enables women to view their social ventures as a means of gender empowerment, helping them to reconcile the paradoxical pressures of normative gender expectations and scaling up their businesses.
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Utilizing the Marxist theory of unequal exchange to explain the terms of trade between nations, this paper elucidates one possible mechanism that…
Abstract
Purpose
Utilizing the Marxist theory of unequal exchange to explain the terms of trade between nations, this paper elucidates one possible mechanism that gives rise to ecologically unequal exchange between developed and developing economies.
Design/methodology/approach
We propose a two-sector linear production model and demonstrate that a decrease in the organic composition of capital and an increase in the rate of surplus value in a sector will lead to a relative price decrease and value transfer out of that particular sector, as well as increasing the environmental costs of trade. Furthermore, we measure the levels of unequal exchange (value transfer) and ecologically unequal exchange of 40 economies and empirically validate their relationship.
Findings
The findings suggest that an important cause of the ecologically unequal exchange is the value transfer between economies caused by the international division of labor and real wage disparities. The inequality in international trade is a significant factor contributing to the gap in the ecological environment level between developed and developing economies.
Originality/value
By introducing the theory of unequal exchange or value transfer into the analysis of ecological unequal exchange, we provide a mathematical framework for analyzing ecological unequal exchange and a method for calculating the scale of ecological unequal exchange and value transfer, thereby enhancing the theoretical depth and practical significance of the ecological unequal exchange theory.
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Doctors' labour and medicines are special necessities for human survival and evolution. Since China launched the healthcare reform, the theoretical circles' discussions have not…
Abstract
Purpose
Doctors' labour and medicines are special necessities for human survival and evolution. Since China launched the healthcare reform, the theoretical circles' discussions have not yet clarified the respective special properties of doctors' labour and medicines as goods and the internal relations between doctors' labour and medicines at the level of the theoretical basis.
Design/methodology/approach
Health is a prerequisite for people's all-round development, a precondition for economic and social development and the people's common aspiration. The all-round moderately prosperous society could not be achieved without people's all-round health.
Findings
The authors believe the socialist relation between doctors' labour and medicines with Chinese characteristics should be one that is people-oriented, and the corporatization of hospitals or the capitalization of doctors' labour should be avoided.
Originality/value
In this paper, the authors explore the particularity of doctors' labour, particularity of medicine production, circulation, consumption and the internal relations between doctors' labour and medicines by using the analytical approach of Marxist political economy while considering the special roles of doctor's labour and medicines in the reproduction of labour power and put forward the theoretical basis for the segregation of doctor's labour and medicines.
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Adaptive reuse of building assets is an important approach to sustainability. Adapting a building for new uses often involves complex factors in the decision-making process…
Abstract
Purpose
Adaptive reuse of building assets is an important approach to sustainability. Adapting a building for new uses often involves complex factors in the decision-making process, particularly in conservation areas. The paper aims to show an evaluation process of the adaptive reuse potential of historic buildings that are subject to change in the Grand Canal area, a world heritage site in Hangzhou, China.
Design/methodology/approach
For this purpose, a model has been established with aggregated views of professionals on the degree to which a variety of factors affect the buildings’ potential for adaptive reuse. The model intends to help prioritise some of the buildings in the area for adaptive reuse, which is important for effective allocation of public resources. Interviews with professionals, analytic hierarchy process and the Delphi method have been used to establish the evaluation model. It is then applied to the Grand Canal area to generate indices for buildings’ adaptive reuse potential and the ranking of priority. The indices are generated through public scoring of historic buildings against the variables and calculated through the model.
Findings
The paper concludes that the evaluation process is an effective way to engage the public in the decision-making process and to balance conflict interests of various stakeholders in the management of historic building assets in conservation areas.
Originality/value
The research has proposed an evaluation model to help set priority of buildings subject to adaptive reuse and to help distribute public fund effectively. It facilitates wide public engagement in the decision-making progress of adaptive reuse of historic buildings.