Yanli Feng, Ke Zhang, Haoyu Li and Jingyu Wang
Due to dynamic model is the basis of realizing various robot control functions, and it determines the robot control performance to a large extent, this paper aims to improve the…
Abstract
Purpose
Due to dynamic model is the basis of realizing various robot control functions, and it determines the robot control performance to a large extent, this paper aims to improve the accuracy of dynamic model for n-Degree of Freedom (DOF) serial robot.
Design/methodology/approach
This paper exploits a combination of the link dynamical system and the friction model to create robot dynamic behaviors. A practical approach to identify the nonlinear joint friction parameters including the slip properties in sliding phase and the stick characteristics in presliding phase is presented. Afterward, an adaptive variable-step moving average method is proposed to effectively reduce the noise impact on the collected data. Furthermore, a radial basis function neural network-based friction estimator for varying loads is trained to compensate the nonlinear effects of load on friction during robot joint moving.
Findings
Experiment validations are carried out on all the joints of a 6-DOF industrial robot. The experimental results of joint torque estimation demonstrate that the proposed strategy significantly improves the accuracy of the robot dynamic model, and the prediction effect of the proposed method is better than that of existing methods.
Originality/value
The proposed method extends the robot dynamic model with friction compensation, which includes the nonlinear effects of joint stick motion, joint sliding motion and load attached to the end-effector.
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Lian-Li Feng and Tian-Tian Zhang
The purpose of this paper is to find homoclinic breather waves, rogue waves and soliton waves for a (3 + 1)-dimensional generalized Kadomtsev–Petviashvili (gKP) equation, which…
Abstract
Purpose
The purpose of this paper is to find homoclinic breather waves, rogue waves and soliton waves for a (3 + 1)-dimensional generalized Kadomtsev–Petviashvili (gKP) equation, which can be used to describe the propagation of weakly nonlinear dispersive long waves on the surface of a fluid.
Design/methodology/approach
The authors apply the extended Bell polynomial approach, Hirota’s bilinear method and the homoclinic test technique to find the rogue waves, homoclinic breather waves and soliton waves of the (3 + 1)-dimensional gKP equation.
Findings
The results imply that the gKP equation admits rogue waves, homoclinic breather waves and soliton waves. Moreover, the authors also find that rogue waves can come from the extreme behavior of the breather solitary wave. The authors analyze the propagation and interaction properties of these solutions to better understand the dynamic behavior of these solutions.
Originality/value
These results may help us to further study the local structure and the interaction of waves in KP-type equations. It is hoped that the results can help enrich the dynamic behavior of such equations.
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With considerable attention paid to the motives and process of idiosyncratic internationalization trajectory of multinationals from emerging economies (EMNCs), little is known on…
Abstract
Purpose
With considerable attention paid to the motives and process of idiosyncratic internationalization trajectory of multinationals from emerging economies (EMNCs), little is known on whether, and if so how, new competitive advantages of EMNCs are created and accumulated over time. MNC and EMNC literature agrees on the importance of external and internal knowledge linkages in technological competence creation. By building upon this framework, this paper aims to evaluate EMNCs’ external and internal knowledge flow patterns by benchmarking their counterparts from mature industrialized countries (MMNCs).
Design/methodology/approach
This study analyzes US patents granted between 2000 and 2014 to leading innovation-oriented EMNCs from China and India, and their matched MMNCs. Being the first to use the US patent and citation data in studying leading innovation-oriented EMNCs, the authors use a descriptive statistical method.
Findings
The findings offer empirical insights of the scale, scope and quality of EMNC technological competence creation. Moreover, in contrast to existing EMNC literature, it is found that EMNC parents have been the most important center of EMNC technological knowledge generation. The matched group comparisons of external and internal knowledge flows further reveal detailed similarities and differences of competence creation between EMNCs and MMNCs, and among EMNCs.
Originality/value
This study represents one of the first attempts to investigate the post-internationalization technological competence creation of EMNCs by using a novel data source. This study sets the foundation to deepen the understanding of EMNC technological competence creation. The findings suggest interesting propositions and offer important implications for future researches.
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Feng Zhang, Chongchong Lyu and Lei Zhu
Empirical results remain unclear as to whether organizational unlearning can improve radical innovation performance. The purpose of this study is to investigate how, and under…
Abstract
Purpose
Empirical results remain unclear as to whether organizational unlearning can improve radical innovation performance. The purpose of this study is to investigate how, and under which conditions, organizational unlearning influences firms’ radical innovation performance.
Design/methodology/approach
Drawing on the knowledge-based view, this study develops a theoretical model that hypothesizes a positive relationship between organizational unlearning and radical innovation performance, which is mediated by knowledge generation strategies. It also proposes that the impact of unlearning on knowledge generation strategies will be moderated by dysfunctional competition. Using survey data from 191 Chinese manufacturing firms, the hierarchical regressions were used to test the hypotheses.
Findings
The empirical results show that organizational unlearning not only impacts radical innovation performance directly, but also indirectly affects radical innovation performance through two distinct types of knowledge generation strategies: (internal) knowledge creation and (external) information searching. Moreover, dysfunctional competition plays a dual role, strengthening the positive relationship between organizational unlearning and information search and weakening the positive relationship between organizational unlearning and knowledge creation.
Research limitations/implications
The present research broadens the understanding of how to promote radical innovation performance, which has great potential to improve the performance of firms on the market. Specifically, it deepens the knowledge of how organizational unlearning facilitates radical innovation performance by focusing on two distinct types of knowledge generation strategies as the crucial links, and enriches existing literature on the effectiveness of organizational unlearning in a dysfunctional competitive environment.
Practical implications
Practicing organizational unlearning for firms’ long-term success requires firms to develop and implement appropriate knowledge generation strategies in accordance with the characteristics of market competition in their operating environment.
Originality/value
This study offers new insights into how and under what conditions organizational unlearning affects radical innovation performance, enhancing the understanding of how organizational unlearning can be implemented to drive firm radical innovation.
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Firms increasingly diversify their technological competencies to achieve different strategic objectives. This study aims to explore the impacts of technological knowledge…
Abstract
Purpose
Firms increasingly diversify their technological competencies to achieve different strategic objectives. This study aims to explore the impacts of technological knowledge characteristics on patenting choices for inventions created by subsidiaries in an uncertain and fast changing environment.
Design/methodology/approach
The data used in this study are patents granted to the world largest firms by the USPTO for inventions attributable to their subsidiaries in China between 1996 and 2005. In addition, the patent data from State Intellectual Property Office (SIPO) of China are used for the matching in terms of filing patent applications in both USA and China for a same piece of technology. A discrete Logit model is used to examine the effects of technological distance and categories on Chinese patent application and international priority.
Findings
The findings suggest that firms have priority to seek international patent protection, instead of host country protection, for valuable subsidiary inventions in their background and marginal technological fields. In addition, a firm may seek host country legal protection simultaneously for inventions built upon knowledge from technologically distant fields.
Research limitations/implications
As we are more interested in protecting technological knowledge, the protection of other types of knowledge, such as organizational knowledge, deserves further research attentions. Moreover, future research may expand current study by including small and medium firms, as well as firms in other developing economies.
Practical implications
While the economic and legal environment in China may have evolved since studied period, the results have practical implications for firms in other developing countries that are at an early stage of catching-up or those in a host location featuring a similar uncertain and fast changing environment. In particular, the study suggests that foreign firm managers would have more strategic choices of patenting than local firms in the host country. For strategically important inventions bridging complex knowledge from different technological areas, firms could seek protection in multiple countries simultaneously, including both home country and other major markets. Furthermore, managers could choose whether or not to protect a particular category of technologies in host country depending on value of the technology to the firm and the IPR protection of host country. Finally, the approach of looking at knowledge-level characteristics, which can be easily measured through readily available intra-firm information, provides managers with a practical and useful tool to make these strategic decisions.
Originality/value
This study represents an effort to extend the understanding on how foreign MNCs could generate and appropriate valuable technologies in an uncertain and fast-changing environment. In particular, the authors focus on how MNCs could use different international patenting patterns to benefit from subsidiary inventions. Whereas previous literature mainly focuses on country-level and firm-level determinants, this study approaches the topic through the lens of knowledge-level factors. By studying how knowledge characteristics determine firm strategic behaviors, the authors offer additional justifications of the knowledge-based view of the firm. Meanwhile, the findings enrich our understanding of an important component of MNC’s global strategies in managing their technologies through selectively patenting in different locations. Firms pursue diversified technologies for different strategic objectives. As subsidiary inventions become a very important source of firm competitiveness, MNCs have to face the trade-off between higher patenting costs and the appropriability of subsidiary generated knowledge. The findings suggest that it is not necessary for MNCs to protect all subsidiary inventions in host countries.
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Feng Zhang, Lei Zhu and Liqun Wei
Whether shareholders’ involvement in management benefits the organization’s performance remains inconclusive. The purpose of this study is to reconcile the conflicting results by…
Abstract
Purpose
Whether shareholders’ involvement in management benefits the organization’s performance remains inconclusive. The purpose of this study is to reconcile the conflicting results by exploring whether and under which contexts shareholder involvement may impact firm innovation performance.
Design/methodology/approach
This study attempts to combine previous theoretical views (reactance and agency theories) to examine a curvilinear effect of shareholder involvement on firm innovation performance based on governance related to cost-benefit analysis. Drawing on data from 174 Chinese manufacturing firms, the hierarchical regressions were used to test the hypotheses.
Findings
The study finds that shareholder involvement has a U-shaped relationship with firm innovation performance. Moreover, ownership incentive strengthens the U-shaped relationship, while monitoring weakens it.
Originality/value
Examination of the U-shaped main effect of shareholder involvement and these contingent factors further explains the mixed empirical results concerning the link between shareholder activism and firm-level performance.
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Xiao-feng Zhang, Xiao-juan Zhang, Lei Li, Gui-quan Li and You-min Xi
This study aims to focus on the authority formation process of Chinese enterprise leaders, with the purpose of finding out how an ordinary newly established firm leader develops…
Abstract
Purpose
This study aims to focus on the authority formation process of Chinese enterprise leaders, with the purpose of finding out how an ordinary newly established firm leader develops into a real top leader and achieves the status of legitimacy in a well-known enterprise.
Design/methodology/approach
Based on constructivist grounded theory, this paper investigates the formation mechanism of entrepreneurial authority in China by using the rich data of Liu Chuan-zhi’s leader activities.
Findings
In the “evolution” path of authority formation, leaders continually consolidate and improve their authority through two classes of exceptional management activities: “emergency rescue” and “promotion activities”. The successful realization of exceptional management activities benefits from a leader’s management experience accumulation and relationship maintenance with the government. In the “design” path of authority formation, leaders consolidate and improve their authority by exercising their position of power. Leaders’ legitimacy is reflected by making strategic decision and demonstrating discretion of position power. Additionally, passing on an inspiring leader’s thoughts and ideas to an organization’s members is accomplished through the construction of organization culture, institutionalization and convention.
Research limitations/implications
First, the findings are based on only Liu Chuan-zhi’s case. The authors still need more cases to compare and develop the findings and seek theoretical saturation in a broader sense. Second, the qualitative analysis is based on secondary data and future research could consider the introduction of interviews, video and other types of research data.
Originality/value
Under the parallel paths which are “evolution” and “design”, the dynamic leader authority formation model in China is founded.
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Chun-Mei Kai, Feng-Jun Zhang, Cong-Liang Cheng and Qian-Bao Chen
The purpose of this paper is to study the influence of different factors on mud performance, find the best conditions and synthesize a new type of anti-collapse drilling polymer…
Abstract
Purpose
The purpose of this paper is to study the influence of different factors on mud performance, find the best conditions and synthesize a new type of anti-collapse drilling polymer mud with higher stability. The anti-collapse mechanism of drilling polymer mud was also suggested.
Design/methodology/approach
Exploring the influence of different molecular weight thickeners, filtrate reducers, soda ash addition and film-forming components on the mud performance, so as to obtain the best ratio of anti-collapse drilling polymer mud.
Findings
The results show that the use of vegetable glue, sulfonate copolymer and vegetable fiber powder can synthesize a high-viscosity, high-stability, collapse-resistant mud. When the mass ratio of vegetable fiber powder: vegetable glue: sulfonate copolymer is 40:1:2, the mud viscosity is 21.2 s, the fluid loss in 30 min is only 12.5 mL, and the mud film thickness is 1.5 mm, which is one ideal anti-collapse polymer mud.
Originality/value
Compared with ordinary polymer mud and bentonite mud, this anti-collapse polymer mud not only uses vegetable glue instead of traditional tackifiers but also effectively uses vegetable fiber powder produced from waste wood, which is environmentally friendly and highly stable specialty. It can effectively improve the safety and quality of construction during drilling in water-sensitive geology.
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Yangkun Wang, Feng Zhang, Shiwen Zhang and Guang Yang
A multi-load available, response reliable and product-friendly method is in urgent need to diagnose the signs of incipient arcing. This paper aims to propose a novel algorithm…
Abstract
Purpose
A multi-load available, response reliable and product-friendly method is in urgent need to diagnose the signs of incipient arcing. This paper aims to propose a novel algorithm that originates the application of correlativity analysis of wavelet high-frequency component in state discrimination and further in arcing detection.
Design/methodology/approach
The proposed method calculates the correlation coefficient between the extraction by wavelet transform of arcing series current and that of normal, compares it with a predefined threshold and outputs a trip signal when eight qualified arcing half cycles within a period of 0.5 s are detected.
Findings
Typical appliances are selected in laboratory for arc detection to test the method which carries on independently of impedance type. The algorithm could be optimized to identify arcing for different kinds of loads, including resistive, inductive, capacitive and switching power supply loads, with a same correlation coefficient threshold.
Practical implications
The arithmetic operations of the method are addition and multiplication, which contribute to efficient data computation and transmission for micro-processor to undertake. The reference optimal sampling rate recommended for the algorithm helps to reduce the processed data volume and shows its promising prospect for portable product development.
Originality/value
This proposed correlativity analysis of wavelet transform component algorithm could classify the tested signal into two categories, which benefits the discrimination of normal and fault states in condition monitoring. Laboratory tests prove that it works effectively in arc detection for the commonly used impedance types of loads and needs no offline self-learning or training of samples.
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Feng Zhang, Youliang Wei and Tao Feng
GraphQL is a new Open API specification that allows clients to send queries and obtain data flexibly according to their needs. However, a high-complexity GraphQL query may lead to…
Abstract
Purpose
GraphQL is a new Open API specification that allows clients to send queries and obtain data flexibly according to their needs. However, a high-complexity GraphQL query may lead to an excessive data volume of the query result, which causes problems such as resource overload of the API server. Therefore, this paper aims to address this issue by predicting the response data volume of a GraphQL query statement.
Design/methodology/approach
This paper proposes a GraphQL response data volume prediction approach based on Code2Vec and AutoML. First, a GraphQL query statement is transformed into a path collection of an abstract syntax tree based on the idea of Code2Vec, and then the query is aggregated into a vector with the fixed length. Finally, the response result data volume is predicted by a fully connected neural network. To further improve the prediction accuracy, the prediction results of embedded features are combined with the field features and summary features of the query statement to predict the final response data volume by the AutoML model.
Findings
Experiments on two public GraphQL API data sets, GitHub and Yelp, show that the accuracy of the proposed approach is 15.85% and 50.31% higher than existing GraphQL response volume prediction approaches based on machine learning techniques, respectively.
Originality/value
This paper proposes an approach that combines Code2Vec and AutoML for GraphQL query response data volume prediction with higher accuracy.