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11 – 20 of over 1000Bo Chen, Yongzhen Yao, Yuhua Huang, Wenkang Wang, Caiwang Tan and Jicai Feng
This paper aims to explore the influences of different process parameters, including laser power, scanning speed, defocusing distance and scanning mode, on the shape features of…
Abstract
Purpose
This paper aims to explore the influences of different process parameters, including laser power, scanning speed, defocusing distance and scanning mode, on the shape features of molten pool and, based on the obtained relationship, realize the diagnosis of forming defects during the process.
Design/methodology/approach
Molten pool was captured on-line based on a coaxial CCD camera mounted on the welding head, then image processing algorithms were developed to obtain melt pool features that could reflect the forming status, and it suggested that the molten pool area was the most sensitive characteristic. The influence of the processing parameters such as laser power, traverse speed, powder feed rate, defocusing distance and the melt pool area was studied, and then the melt pool area was used as the characteristic to detect the forming defects during the cladding and additive manufacturing process.
Findings
The influences of different process parameters on molten pool area were explored. Based on the relationship, different types of defects were accurately detected through analyzing the relationship between the molten pool area and time.
Originality/value
The findings would be helpful for the quality control of laser additive manufacturing.
Details
Keywords
Bo Chen, Zheng Meng, Kai Yang, Yongzhen Yao, Caiwang Tan and Xiaoguo Song
The purpose of this paper is to predict and control the composition during laser additive manufacturing, since composition control is important for parts manufactured by laser…
Abstract
Purpose
The purpose of this paper is to predict and control the composition during laser additive manufacturing, since composition control is important for parts manufactured by laser additive manufacturing. Aluminum and steel functionally graded material (FGM) were manufactured by laser metal deposition, and the composition was analyzed by means of spectral analysis simultaneously.
Design/methodology/approach
The laser metal deposition process was carried out on a 5 mm thick 316L plate. Spectral line intensity ratio and plasma temperature were chosen as two main spectroscopic diagnosis parameters to predict the compositional variation. Single-trace single-layer experiments and single-trace multi-layer experiments were done, respectively, to test the feasibility of the spectral diagnosis method.
Findings
Experiment results showed that with the composition of metal powder changing from steel to aluminum, the spectral intensity ratio of the characteristic spectral line is proportional to the elemental content in the plasma. When the composition of deposition layers changed, the characteristic spectrum line intensity ratio changed obviously. And the linear chemical composition analysis results confirmed the gradient composition variation of the additive manufacturing parts. The results verified the feasibility of composition analysis based on spectral information in the laser additive manufacturing process.
Originality/value
The composition content of aluminum and steel FGM was diagnosed by spectral information during laser metal deposition, and the relationship between spectral intensity and composition was established.
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Keywords
The last few decades have seen the rapid emergence of two transformative streams in large firms. The first is the development of project management, aimed at improving the…
Abstract
Purpose
The last few decades have seen the rapid emergence of two transformative streams in large firms. The first is the development of project management, aimed at improving the performance of innovation management, while the second, the internationalization of innovation organizations and processes in response to strategies of redeployment toward emerging countries. Both streams have been closely analyzed in the fields of project management and international management, respectively. However, the links between the two have been less studied. The purpose of this paper is to consider the hypothesis that a firm’s projectification might have an important impact on its pattern of internationalization in innovation.
Design/methodology/approach
First, we present the models of internationalization of innovation processes used in the multinational corporation literature. This field essentially focuses on the components of permanent organizations: global internationalization strategy and legacy, R&D footprint, characterization of local subsidiaries and the role of central head offices. Projects figure only as a context in which those elements operate, not as a structuring variable of the global innovation process pattern. The authors challenge this view by exploring whether the specificities of the firm’s projectification pattern can influence how it builds its global innovation process. The paper is based on a longitudinal case where the authors analyze the organizational transition within the Renault group, an emblematic case of a multinational that implemented a spectacular internationalization transition in the 2000s.
Findings
Our results demonstrate project organizing’s major impact on the internationalization patterns of innovation processes within the firm. They show how the deployment of a polycentric innovation footprint has been the consequence of a specific projectification transition, giving the project and program functions the autonomy to transgress centralized product development norms to adapt their project to the local environment; use the initial breakthrough project as the foundation for a new and specific global product development network through a lineage logic; and sustain this innovation global network as a permanent process of the firm.
Research limitations/implications
The paper demonstrates the importance of the organization’s projectification characteristics as an important vector for successfully implementing the most advanced internationalization strategies (i.e. reverse innovation) and innovation processes models (i.e. integrated networks).
Practical implications
The paper characterizes project management related conditions that can govern the success of innovation strategies in high-growth emerging countries: the autonomy and empowerment of project functions; colocation and integration of teams; existence of a program function; and HR policies capable of supporting lineage management and project-to-project learning processes.
Originality/value
Bridging project management literature with multinational management literature. Demonstrate the key impact of projectification on internationalization pattern of the firm. Longitudinal analysis of a firm internationalization transition on a ten-year period.
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The Communist revolution in China has led to the appearance in this country of increasing numbers of Chinese books in Russian translation. The Chinese names in Cyrillic…
Abstract
The Communist revolution in China has led to the appearance in this country of increasing numbers of Chinese books in Russian translation. The Chinese names in Cyrillic transcription have presented many librarians and students with a new problem, that of identifying the Cyrillic form of a name with the customary Wade‐Giles transcription. The average cataloguer, the first to meet the problem, has two obvious lines of action, and neither is satisfactory. He can save up the names until he has a chance to consult an expert in Chinese. Apart altogether from the delay, the expert, confronted with a few isolated names, might simply reply that he could do nothing without the Chinese characters, and it is only rarely that Soviet books supply them. Alternatively, he can transliterate the Cyrillic letters according to the system in use in his library and leave the matter there for fear of making bad worse. As long as the writers are not well known, he may feel only faintly uneasy; but the appearance of Chzhou Ėn‐lai (or Čžou En‐laj) upsets his equanimity. Obviously this must be entered under Chou; and we must have Mao Tse‐tung and not Mao Tsze‐dun, Ch'en Po‐ta and not Chėn' Bo‐da. But what happens when we have another . . . We can hardly write Ch'en unless we know how to represent the remaining elements in the name; yet we are loth to write Ch'en in one name and Chėn' in another.
This study especially concerns the causal relationship between official defense expenditure and economic development for mainland China from 1953 to 2007 by employing a…
Abstract
This study especially concerns the causal relationship between official defense expenditure and economic development for mainland China from 1953 to 2007 by employing a combination of VAR models and the Granger Causality Test. The final conclusions are diverse in varied time periods where no evidence showing the Chinese economy had an effect on its military development or the reverse. Nevertheless, military spending benefited the economy after 1989 when the development of defense was running on a new path. This study also includes a proxy series of Western estimated data, say SIPRI, which has a result that resembles Chinese official data over the period 1989–2007.