This study and its centering device with Archimedes spirals designed on hydrodynamic lubrication aims to reduce the deviation of deep holes because the drill tube is long and easy…
Abstract
Purpose
This study and its centering device with Archimedes spirals designed on hydrodynamic lubrication aims to reduce the deviation of deep holes because the drill tube is long and easy to deviate in deep hole machining.
Design/methodology/approach
The centering device with Archimedes spirals was designed and fixed between the drilling tool and the drill tube. The wall of the deep hole and the novel centering device formed three wedge-shaped oil films. When the workpiece rotated relative to the centering device, pressure was generated in the oil films; therefore, three oil films supported drilling system as oil films support rotating journal in the full-film hydrodynamic bearing.
Findings
When the Boring and Trepanning Association (BTA) drilling system was equipped with the centering device, the cutting oil flowed smoothly and carried all the iron chips; the motors run normally; no additional vibration or sound was detected during processing; the surface of the centering device was smooth; and the deviation of the drilled deep hole decreased with a high probability.
Originality/value
To the best of the authors’ knowledge, no one has designed and made the centering device with Archimedes spirals to reduce the deviation of deep holes in deep hole machining. Three oil films formed by the centering device with Archimedes spirals support drilling system and prevent it from deviating, which has never appeared before and is creative.
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Zheng Jiang, Haobo Qiu, Ming Zhao, Shizhan Zhang and Liang Gao
In multidisciplinary design optimization (MDO), if the relationships between design variables and some output parameters, which are important performance constraints, are complex…
Abstract
Purpose
In multidisciplinary design optimization (MDO), if the relationships between design variables and some output parameters, which are important performance constraints, are complex implicit problems, plenty of time should be spent on computationally expensive simulations to identify whether the implicit constraints are satisfied with the given design variables during the optimization iteration process. The purpose of this paper is to propose an ensemble of surrogates-based analytical target cascading (ESATC) method to tackle such MDO engineering design problems with reduced computational cost and high optimization accuracy.
Design/methodology/approach
Different surrogate models are constructed based on the sample point sets obtained by Latin hypercube sampling (LHS) method. Then, according to the error metric of each surrogate model, the repeated ensemble of surrogates is constructed to approximate the implicit objective functions and constraints. Under the framework of analytical target cascading (ATC), the MDO problem is decomposed into several optimization subproblems and the function of analysis module of each subproblem is simulated by repeated ensemble of surrogates, working together to find the optimum solution.
Findings
The proposed method shows better modeling accuracy and robustness than other individual surrogate model-based ATC method. A numerical benchmark problem and an industrial case study of the structural design of a super heavy vertical lathe machine tool are utilized to demonstrate the accuracy and efficiency of the proposed method.
Originality/value
This paper integrates a repeated ensemble method with ATC strategy to construct the ESATC framework which is an effective method to solve MDO problems with implicit constraints and black-box objectives.
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Shiyi Chen and Wang Li
With China’s economic growth slowing down and the growth rate of fiscal revenue decreasing, the pressure on local government debts is further increasing. Under this background, it…
Abstract
Purpose
With China’s economic growth slowing down and the growth rate of fiscal revenue decreasing, the pressure on local government debts is further increasing. Under this background, it is of great significance to clarify the relation between local government debts and China’s economic growth in order to give full play to the positive role of local debts in stabling growth. The paper aims to discuss this issue.
Design/methodology/approach
Therefore, this paper explores the impact of Chinese local government debt on economic growth from theoretical and empirical aspects, respectively, and compares the regional differences between different debts and economic growth dynamics.
Findings
In the theoretical model part, this paper constructs a three-sector dynamic game model, under the two circumstances of whether local government is subject to debt constraints, and examines the relation between local government debt and economic growth and other variables through numerical simulation. Research shows that when the government is not constrained by debt, there is an inverted “U” relation between government debt and economic growth. When the government is constrained by debt, the economic growth rate gradually decreases as the government debt increases.
Originality/value
In the theoretical analysis part, this paper tries to estimate the amount of local debts under different calibers and examines the impact of different types of local government debts on China’s economic growth and their regional differences. The results show that excessive accumulation of government hidden debts in the eastern region is not conducive to economic growth, while explicit debts in the central and western regions significantly contribute to local economic growth. The results of empirical analysis are basically consistent with the predictions of the theoretical model.
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The purpose of this paper is to describe the complicated characteristics of the environment, the relationship between complicated organization and organizational transformation…
Abstract
Purpose
The purpose of this paper is to describe the complicated characteristics of the environment, the relationship between complicated organization and organizational transformation, and the coupling domino effect between the complication of external environment and organizational complexity by making conceptual systematic analysis.
Design/methodology/approach
The relative stability and certainty of the organizational structure are being replaced by uncertainty and complexity. Organizational learning and its reform are becoming all the more important to gain organizational competitive advantage. This paper designs the system analysis method to discuss the complexity of organizational environment, the relationship between organizational complexity and organizational structure reform, and also the coupling effect of the complexity of external environment and that of the organization.
Findings
It is found that organizational learning, the ways of strategic reform, and the focal point must remain consistent under the complicated environment.
Research limitations/implications
The main limitation is how to construct the mathematical models describing complicated characteristics of the environment.
Practical implications
The paper contains very useful advice for human resource managers.
Originality/value
The paper focuses on the selection of learning patterns and strategic management of different organizational learning and the reform of organizational structure.
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Ming Zhao, Zhengdong Huang and Liping Chen
The purpose of this paper is to introduce a new method to carry out the design optimization of the tool head system in the heavy‐duty machine tool where closed hydrostatic…
Abstract
Purpose
The purpose of this paper is to introduce a new method to carry out the design optimization of the tool head system in the heavy‐duty machine tool where closed hydrostatic guideways with multiple pockets are employed.
Design/methodology/approach
A more accurate method of pressure calculation for closed hydrostatic guideways is introduced. Then, a multidisciplinary design optimization (MDO) model is formulated for design of a tool head system, which minimizes the highest pocket pressure under some constraints from machining accuracy and vibration resistance requirements as well as constraints from ballscrew design specifications. Finally, a metamodel‐based design space alternation (DSA) strategy is proposed to solve the optimization problem.
Findings
The results show that the maximum pocket pressure in a tool head system can be reduced over 47 percent with a proper design while all the constraints are satisfied. As a consequence, the tool head system can safely work under the maximum output pressure of oil supply system.
Originality/value
This paper introduces a more accurate method of pressure calculation for multi‐pocket closed hydrostatic guideways, develops a metamodel‐based MDO model for the tool head system, and proposes a DSA strategy to solve the MDO problem.
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Michelle Chaotzu Wang and James Quo-Ping Lin
The purpose of this paper is to introduce a progressive strategy of the National Palace Museum (NPM) using new media art exhibitions as a creative marketing tool to interpret its…
Abstract
Purpose
The purpose of this paper is to introduce a progressive strategy of the National Palace Museum (NPM) using new media art exhibitions as a creative marketing tool to interpret its collection, generate cultural value and navigate the greater global context.
Design/methodology/approach
A review of museum marketing literature and the challenges presented by Taiwan’s sociopolitical situation contextualize discussions on marketing activities and the emergence of museum-commissioned new media art at the NPM within the past two decades.
Findings
Democratic potency inherent in the digital medium has enabled the NPM to transcend the conflicting cultural perceptions surrounding its collection and fulfill the function of market expansion and cultural transmission.
Originality/value
Specialized heritage museums, such as the NPM, do not traditionally create or collect contemporary artworks that engage in ongoing cultural dialogues. This paper brings into view the novelty of using the digital medium to generate cultural value as exemplified in the new media art commissioned by the NPM.
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Zhiyuan Huang, Haobo Qiu, Ming Zhao, Xiwen Cai and Liang Gao
Popular regression methodologies are inapplicable to obtain accurate metamodels for high dimensional practical problems since the computational time increases exponentially as the…
Abstract
Purpose
Popular regression methodologies are inapplicable to obtain accurate metamodels for high dimensional practical problems since the computational time increases exponentially as the number of dimensions rises. The purpose of this paper is to use support vector regression with high dimensional model representation (SVR-HDMR) model to obtain accurate metamodels for high dimensional problems with a few sampling points.
Design/methodology/approach
High-dimensional model representation (HDMR) is a general set of quantitative model assessment and analysis tools for improving the efficiency of deducing high dimensional input-output system behavior. Support vector regression (SVR) method can approximate the underlying functions with a small subset of sample points. Dividing Rectangles (DIRECT) algorithm is a deterministic sampling method.
Findings
This paper proposes a new form of HDMR by integrating the SVR, termed as SVR-HDMR. And an intelligent sampling strategy, namely, DIRECT method, is adopted to improve the efficiency of SVR-HDMR.
Originality/value
Compared to other metamodeling techniques, the accuracy and efficiency of SVR-HDMR were significantly improved. The SVR-HDMR helped engineers understand the essence of underlying problems visually.
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With the development of economy and the progress of science and technology, the function of Luoyang city is constantly enriched and expanded. The city is no longer a simple area…
Abstract
With the development of economy and the progress of science and technology, the function of Luoyang city is constantly enriched and expanded. The city is no longer a simple area for people to live in. The function structure of the city is affected by the external factors and is constantly expanding. Urban logistics is one of the important influencing factors. To more comprehensively and accurately understand the status and role of logistics network space in urban planning, the characteristics and development law of urban logistics structure from the theoretical point of view are analyzed in this paper with Luoyang City as the research background. The city logistics function is determined as one of the main factors affecting the economic growth of the city is determined through the literature search method, consulting professionals and other research methods. Urban road planning and design are the focus of the study; the planning and development of urban logistics road network in Luoyang City are compared and analyzed. In full consideration of the necessity of the optimization of the urban logistics network space, the preliminary optimization scheme design and suggestion of Luoyang logistics is introduced. At the end of this paper, the sustainable development and the status of the future urban logistics function are analyzed and prospected. Continuous research and analysis of multiple subjects and angles are still needed.
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This study aims at providing exploratory insights into the initiative and capabilities of Chinese SMEs to develop and utilize diverse networks to support internationalization…
Abstract
This study aims at providing exploratory insights into the initiative and capabilities of Chinese SMEs to develop and utilize diverse networks to support internationalization. Such network development and utilization efforts are fundamental to the analysis and explanation of Chinese firms’ internationalization patterns and outcomes. Extending from the existing network studies in the Chinese context that generally put emphasis on strong‐tie and ethnic‐oriented networks, this paper investigates and explains explicitly the use and effects of both strong‐ and weak‐tie networks in the international development of Chinese SMEs. Indepth case studies on four rapidly internationalized Chinese SMEs are conducted. The case findings demonstrate that weak‐tie networks are essential to the firms’ business development in foreign markets; and were proactively developed and utilized in the course of the firms’ development. The cases also provide alternative perspectives to the beliefs and values underpinning strong‐tie networks presumed in existing literature. The findings draw attention to the changing business values and approaches of the Chinese firms aiming at developing internationally. Managerial implications concerning the significant influence of effective networking on internationalization are pinpointed.