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Zhihao Wang, Wenliang Chen, Min Wang, Qinghe Xu and Can Huang
The purpose of this study is to improve the position and posture accuracy of posture alignment mechanism. The automatic drilling and riveting machine is an important…
Abstract
Purpose
The purpose of this study is to improve the position and posture accuracy of posture alignment mechanism. The automatic drilling and riveting machine is an important equipment for aircraft assembly. The alignment accuracy of position and posture of the bracket type posture alignment mechanism has a great influence on the operation effect of the machine. Therefore, it is necessary to carry out the kinematic calibration.
Design/methodology/approach
Based on analysis of elastic deformation of the bracket and geometric errors of the posture alignment mechanism, an improved method of kinematic calibration was proposed. The position and posture errors of bracket caused by geometric errors were separated from those caused by gravity. The method of reduction of dimensions was applied to deal with the error coefficient matrix in error identification, and it did not change the coefficient of the error terms. The target position and its posture were corrected to improve the error compensation accuracy. Furthermore, numerical simulation and experimental verification were carried out.
Findings
The simulation and experimental results show that considering the influence of the elastic deformation of the bracket on the calibration effect, the error identification accuracy and compensation accuracy can be improved. The maximum value of position error is reduced from 5.33 mm to 1.60 × 10−1 mm and the maximum value of posture error is reduced from 1.07 × 10−3 rad to 6.02 × 10−4 rad, which is superior to the accuracy without considering the gravity factor.
Originality/value
This paper presents a calibration method considering the effects of geometric errors and gravity. By separating position and posture errors caused by different factors and correcting the target position and its posture, the results of the calibration method are greatly improved. The proposed method might be applied to any parallel mechanism based on the positioner.
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Yuan Mao Huang and Yu‐Chung Liao
The purpose of this paper is to enhance the method developed by previous researchers. In addition to using the combined interference matrix, the combined connection matrix…
Abstract
Purpose
The purpose of this paper is to enhance the method developed by previous researchers. In addition to using the combined interference matrix, the combined connection matrix and the combined contact matrix of product components, the disassembly sequence matrix and the combined instability matrix with platform to evaluate instability of sub‐assemblies are built, and effects of changes of sub‐assembly disassembly directions or tools and the effect of gravity are considered to obtain the best disassembly sequence for a product with many components. A computer program is generated and results of two cases are compared with those of the available studies.
Design/methodology/approach
The methodology includes the combined interference matrix, the combined contact matrix and the combined connection matrix of components for a product. The combined instability matrix of sub‐assemblies, changes of sub‐assembly disassembly direction or tools, and the effect of gravity during operation are considered. The binary number system is used to simplify relations among components of a product.
Findings
This methodology enhances the existing method and software is generated. Results of two cases are compared and show the same optimum disassembly processes as those obtained from other researchers.
Research limitations/implications
All matrices are defined by the directions of x, y and z with three axes perpendicular to each other. The computer program generated cannot be used for a product with components that must be disassembled in the directions different from the axes.
Practical implications
Two cases are used to investigate feasibility of the proposed methodology with the computer program generated. The first one is an electric drill, and the second one is a flash lighter.
Originality/value
The methodology described in this paper is feasible for study of disassembly processes of products. The software generated can be used to obtain the optimum disassembly process of products.
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This paper studies the empirical application of an asset pricing model derived from the irrational individual behavior of loss aversion. Previous research using loss…
Abstract
This paper studies the empirical application of an asset pricing model derived from the irrational individual behavior of loss aversion. Previous research using loss aversion asset pricing finds conclusive evidence that estimations match market equity premium and volatility using simulation data. We find that within its empirical application, the estimated errors are comparable to errors estimated from the capital asset pricing model. This study of the correlations between rational and irrational asset pricing model from the empirical results finds validity for both estimated values. Finally, we see the importance of cultures, economic development and financial development on asset pricing through an empirical examination of five pacific-basin countries in the estimation of asset pricing models.
L. Sun, W.M. Huang, H.B. Lu, C.C. Wang and J.L. Zhang
– This paper aims to present a review on utilizing shape memory technology (SMT) for active assembly/disassembly, i.e. assembly/disassembly without physically touching.
Abstract
Purpose
This paper aims to present a review on utilizing shape memory technology (SMT) for active assembly/disassembly, i.e. assembly/disassembly without physically touching.
Design/methodology/approach
The fundamentals behind the shape memory effect (SME) in materials, in particular shape memory alloys (SMAs) and polymers, which are the cornerstones of SMT, are introduced, together with the possible approaches to implement this effect in active assembly/disassembly. Example applications for not only active assembly/ disassembly, but also programmed active disassembly are presented.
Findings
The advantages of utilizing SMT over conventional assembly/disassembly techniques are identified.
Originality/value
The paper introduces the fundamentals behind the SME and the basic approaches to implement the SMT in not only active assembly/disassembly, but also programmed active assembly.
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Hongbin Huang, Guanghui Jin and Jingnan Chen
The purpose of this paper is to expand the investor sentiment’s effect on investment efficiency to the layer of “credit financing,” studying whether investor sentiment can…
Abstract
Purpose
The purpose of this paper is to expand the investor sentiment’s effect on investment efficiency to the layer of “credit financing,” studying whether investor sentiment can affect credit financing level and the inner mechanism of the effect.
Design/methodology/approach
The authors obtain firm-level data from the Shanghai and Shenzhen stock markets and using panel estimation techniques examine whether investor sentiment can affect credit financing level and the inner mechanism of the effect.
Findings
This paper finds that credit financing plays the role of partial media in the process of investor sentiment affecting investment efficiency. Based on the funds increasing effect, with the high-investor sentiment and increasing credit financing, corporations alleviate the financing constraints, but also provide a convenient for the abuse of corporate funds. So, investor sentiment positively associates with enterprises’ overinvestment, while investor sentiment negatively associates with enterprises’ underinvestment. Relying on the particular system background and property right environment in China, this paper finds that investor sentiment has an effect on the overinvestment of state-owned enterprises and the underinvestment of private enterprises through credit financing channel, while it does not function in the overinvestment of private enterprises. The reason of the difference is that under the soft budget constraint in the country, the credit preference of state-owned enterprises and the creditor’s rights management of banks are partially absent.
Research limitations/implications
By fusing the special financial environment and institutional background, this thesis further includes in the analysis frame the difference in governance effect by credit financing between state-owned and privately owned listed companies, and further analyzes the difference in impact on investment efficiency in enterprises of different natures after investor sentiment has affected enterprise credit financing.
Practical implications
This paper has verified the constraint assumption and deepened the research work on bank credit supply and answered practical questions such as whether the banks in the country exercise supervision function over the listed companies and on which kind of listed companies the supervision function plays a more effective role.
Social implications
As an unofficial substitution mechanism, bank-enterprise relationship can elevate the investment efficiency by private owned enterprises. Based on the timely research results on credit financing, reference is provided for private listed companies to utilize investor sentiment to improve its investment efficiency.
Originality/value
This paper has proved the specific path which creates the dual effects on resources allocation by investor sentiment, that is, the intermediary transmission in credit financing, clarifying the mechanism of action by which investor sentiment affects the efficiency of enterprise investment and making incremental contribution to the research of how investor sentiment affects the efficiency of enterprise investment.
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Chien-Feng Huang, Tsung-Nan Hsieh, Bao Rong Chang and Chih-Hsiang Chang
Stock selection has long been identified as a challenging task. This line of research is highly contingent upon reliable stock ranking for successful portfolio…
Abstract
Purpose
Stock selection has long been identified as a challenging task. This line of research is highly contingent upon reliable stock ranking for successful portfolio construction. The purpose of this paper is to employ the methods from computational intelligence (CI) to solve this problem more effectively.
Design/methodology/approach
The authors develop a risk-adjusted strategy to improve upon the previous stock selection models by two main risk measures – downside risk and variation in returns. Moreover, the authors employ the genetic algorithm for optimization of model parameters and selection for input variables simultaneously.
Findings
It is found that the proposed risk-adjusted methodology via maximum drawdown significantly outperforms the benchmark and improves the previous model in the performance of stock selection.
Research limitations/implications
Future work considers an extensive study for the risk-adjusted model using other risk measures such as Value at Risk, Block Maxima, etc. The authors also intend to use financial data from other countries, if available, in order to assess if the method is generally applicable and robust across different environments.
Practical implications
The authors expect this risk-adjusted model to advance the CI research for financial engineering and provide an promising solutions to stock selection in practice.
Originality/value
The originality of this work is that maximum drawdown is being successfully incorporated into the CI-based stock selection model in which the model's effectiveness is validated with strong statistical evidence.
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– The purpose of this paper is to understand genomics scientists’ perceptions in data quality assurances based on their domain knowledge.
Abstract
Purpose
The purpose of this paper is to understand genomics scientists’ perceptions in data quality assurances based on their domain knowledge.
Design/methodology/approach
The study used a survey method to collect responses from 149 genomics scientists grouped by domain knowledge. They ranked the top-five quality criteria based on hypothetical curation scenarios. The results were compared using χ2 test.
Findings
Scientists with domain knowledge of biology, bioinformatics, and computational science did not reach a consensus in ranking data quality criteria. Findings showed that biologists cared more about curated data that can be concise and traceable. They were also concerned about skills dealing with information overloading. Computational scientists on the other hand value making curation understandable. They paid more attention to the specific skills for data wrangling.
Originality/value
This study takes a new approach in comparing the data quality perceptions for scientists across different domains of knowledge. Few studies have been able to synthesize models to interpret data quality perception across domains. The findings may help develop data quality assurance policies, training seminars, and maximize the efficiency of genome data management.
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To share the experience of two library fund‐raisers with other development officers.
Abstract
Purpose
To share the experience of two library fund‐raisers with other development officers.
Design/methodology/approach
Uses interviews with two successful academic library fund‐raisers to have them share what they have learned.
Findings
Raising funds for any institution can be one of both the hardest and the most rewarding jobs one can do. It requires a lot of personal attention and patience.
Originality/value
Identifies five key elements that should be a part of any successful development officer's job.
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The purpose of this paper is to present the findings of a study that identified and assessed the barriers to client involvement in health and safety (H&S) in the Nigerian…
Abstract
Purpose
The purpose of this paper is to present the findings of a study that identified and assessed the barriers to client involvement in health and safety (H&S) in the Nigerian construction industry.
Design/methodology/approach
On the basis of literature review and a pilot study, structured questionnaires were designed and administered to clients and their representatives in ongoing construction projects in Nigeria. Descriptive and inferential statistics were then adopted while analysing the data.
Findings
The research reveals that the major barriers to client involvement in H&S in Nigeria’s construction industry focus on the gaps created by lack of H&S legislation in specifying client roles and responsibilities in H&S, trust and confidence in the supply chain, low levels of awareness at various levels, procurement issues, the attitudes of the various members of the project team and resource-related issues. In total, 20 barriers to client involvement in H&S were identified and assessed.
Practical implications
Policy makers will find the study beneficial as it provides a good understanding of the issues to address while making policies that seek to involve the client in H&S in Nigeria.
Originality/value
While the findings offer insight on the barriers to client involvement in H&S in Nigeria’s construction industry, the study also contributes to the discourse in developing countries. The paper recommends transparent steps in procurement, H&S legislation that factors in economic incentives and community and financial institutions contributions to involving clients in H&S. The study is the first attempt to investigate the barriers to client involvement in construction H&S in Nigeria, contributing to the dearth of H&S literature in Nigeria.
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