Yang Chuangui, Liu Xingbao, Yue Xiaobin, Mi Liang, Wang Junwen, Xia Yangqiu, Yu Hailian and Chen Heng
This paper aims to solve the nonlinear problem in the uncertainty evaluation of the measurement of the positioning repeatability (RP) of industrial robots and provide guidance to…
Abstract
Purpose
This paper aims to solve the nonlinear problem in the uncertainty evaluation of the measurement of the positioning repeatability (RP) of industrial robots and provide guidance to restrict the uncertainty of measurement of RP (uRP).
Design/methodology/approach
Firstly, some uncertain sources existing in the measurement procedure of RP are identified. Secondly, the probability distribution function (PDF) of every source is established on the basis of its measurements. Some spatial combined normal distributions are adopted. Then, a method, based on Monte Carlo method (MCM) and established measurement model, is developed for the estimation of uRP. Thirdly, some tests are developed for the identification and validation of the selected PDFs of uncertain sources. Afterwards, the proposed method is applied for the evaluation and validation of the uRP. Finally, influence analyses of some key factors are proposed for the quantification of their relative contributions to uRP.
Findings
Results show that the proposed method can reasonably and objectively estimate the uRP of the selected industrial robot, and changes of the industrial robots’ position and the laser trackers measurement are correlated. Additionally, the uRP of the selected industrial robot can be restricted by using the results of its key factors on uRP.
Originality/value
This paper proposes the spatial combined normal distribution to model the uncertainty of the repeatability of the laser tracker and industrial robot. Meanwhile, the proposed method and influence analyses can be used in estimating and restricting the uRP and thus useful in determining whether the RP of a tested industrial robot meets its requirements.
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B. Shirinzadeh, P.L. Teoh and M. Roberts
Fettling is the process of removing excess material from castings. This excess material is often formed at the die’s parting lines during the casting process as molten material is…
Abstract
Fettling is the process of removing excess material from castings. This excess material is often formed at the die’s parting lines during the casting process as molten material is injected into the die at high pressure. By using a robot as a positioning tool for the fettling operation, the process can be carried out safely and with consistent results. This paper proposes a computer‐assisted robotic fettling technique using visual feedback. In particular, emphasis is placed on the establishment of a technique and investigating its performance for the determination of the casting profile. Also examines the process parameters associated with high‐speed fettling operations. Further, the experimental set‐up employed and the results obtained are also presented.
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Richard C. Leventhal and Andree Swanson
The purpose of this paper is to identify resources that are available in the online marketing classroom and to further contemplate the applications for marketing managers. The…
Abstract
Purpose
The purpose of this paper is to identify resources that are available in the online marketing classroom and to further contemplate the applications for marketing managers. The authors explore the rationale for using technology to deliver course material and the positive results that accrue in terms of these efforts.
Design/methodology/approach
An exploratory qualitative research design was used for this study so as to gain broad perspective of technology’s application to the classroom.
Findings
Four types of learners exist: visual learners, auditory learners, 30 read and write learners and kinesthetic learners (Fleming and Mills, 1922a, 1922b). All four types must be addressed in the online learning environment.
Practical implications
Many educators in higher education will use various forms of rudimentary technology in the classroom, but have yet to embrace or understand the full potential of such applications. Online learning uses both synchronous and asynchronous techniques to engage the student so as to improve the individual’s knowledge, skills and abilities.
Originality/value
Technology applications to the marketing classroom have become a necessity for delivering course content to a wide audience of individual learners, both in higher education and in industry as well.
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Bijan Shirinzadeh, Pek Loo Teoh, Chee Wei Foong and YongDong Liu
Laser interferometry‐based sensing (LIS) technique has been proposed and established recently to track and perform dynamic measurements on a moving end‐effector of a robot…
Abstract
Laser interferometry‐based sensing (LIS) technique has been proposed and established recently to track and perform dynamic measurements on a moving end‐effector of a robot manipulator. In this paper, a technique using LIS system to perform guidance of a manipulator is proposed. The LIS system is used as a sensor to guide the end‐effector of a robot manipulator. This is to be accomplished through the implementation of guidance error determination and compensation, and path generation in the control algorithm. This technique can be used to accurately guide the manipulator’s end‐effector to a specified location or along a specified path with a high level of accuracy. The structure and various components within the system and the control strategy are also presented.
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Arathai Din Eak and Nagaletchimee Annamalai
This systematic literature review paper critically examines the effectiveness of screencast feedback compared with text feedback in promoting student learning outcomes in online…
Abstract
Purpose
This systematic literature review paper critically examines the effectiveness of screencast feedback compared with text feedback in promoting student learning outcomes in online higher education. This paper aims to contribute to the ongoing discussion surrounding feedback modalities and their impact on online learning environments.
Design/methodology/approach
This paper adopts a systematic review approach to synthesise and analyse existing studies investigating the use of screencast feedback in online higher education settings. A comprehensive search and selection process was employed to identify relevant literature. The selected studies were then analysed for their methodologies, findings and implications. This paper seeks to provide an overview of the current state of research, highlighting the benefits, challenges and potential impacts of screencast feedback on student learning outcomes.
Findings
The findings of this paper suggest that while there is a positive perception of screencast feedback among students and instructors, drawing definitive conclusions about its superiority over text feedback remains at the very beginning. Students generally appreciate the personalised, supportive and engaging nature of screencast feedback, particularly within the online learning context. However, challenges such as technical barriers and potential workload implications for instructors are also noted. Further empirical research is needed to comprehensively evaluate the comparative efficacy of screencast feedback, considering factors like online engagement, digital literacy and the impact on diverse student populations.
Research limitations/implications
This review underscores the acute necessity for expansive and meticulously designed studies that can provide conclusive insights into the authentic potential of screencast feedback and its resonance within the unique landscape of online learning. Through rigorous inquiry, educators can discern the optimal strategies for harnessing the advantages of screencast feedback to enhance student learning outcomes, aligning harmoniously with the dynamics of virtual classrooms.
Practical implications
Screencast feedback emerges as a promising avenue to foster meaningful connections between instructors and learners. The review highlights that screencast feedback engenders a more dialogic interaction between lecturers and students, resulting in personalised, supportive and engaging feedback experiences.
Social implications
The systematic review conducted underscores the positive reception of screencast feedback from both students and lecturers in this context. The findings are consistent with the principles of social constructivist theory, suggesting that the interactive and personalised nature of screencast feedback facilitates a richer educational experience for students, even within the confines of virtual classrooms (Vygotsky, 1978).
Originality/value
This innovative blend of methodologies contributes new insights that can inform educational practices and pedagogical strategies in online learning environments.
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Lily Wong, Arthur Tatnall and Stephen Burgess
The move towards “blended learning”, consisting of a combination of online and face-to-face teaching, continues to gain pace in universities around the world. It is important…
Abstract
Purpose
The move towards “blended learning”, consisting of a combination of online and face-to-face teaching, continues to gain pace in universities around the world. It is important, however, to question the quality of this learning. The OECD has made use of a model of “Readiness, Intensity and Impact” for investigating the adoption and use of eBusiness technologies. The purpose of this paper is to propose a framework, based on this model and adapted for blended learning, to assess the readiness, intensity of adoption and impact on blended learning offerings. The framework is tested via a description of how one university has adopted and used blended learning, and investigates the quality of the learning from this approach.
Design/methodology/approach
The framework is tested via a case study involving the assessment of a blended learning approach to the delivery of a first-year undergraduate accounting unit at Victoria University, Australia. Various approaches to delivery are assessed over a two-year period. The results are drawn from a survey specifically designed to identify students’ attitudes towards blended learning.
Findings
Despite having three new online options readily available for students to access, there was strong support for face-to-face delivery methods. In relation to the framework, the assessment suggested that certain aspects of the university's blended learning approach could be investigated further (particularly student readiness for different blended learning options and an overall assessment of the impact of a blended approach), to provide a more holistic view of the readiness to adopt and impact of the blended learning offerings.
Originality/value
The value of this contribution lies in the development of a unique framework to assess the impact of blended learning approaches from the viewpoint of student readiness and intensity of separate delivery approaches – whilst maintaining the need to evaluate the effectiveness of blended learning as an overall package.
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The industrial robot has high repeatability but low accuracy. With the industrial robot being widely used in complicated tasks, e.g. arc welding, offline programming and surgery…
Abstract
Purpose
The industrial robot has high repeatability but low accuracy. With the industrial robot being widely used in complicated tasks, e.g. arc welding, offline programming and surgery, accuracy of the robot is more and more important. Robot calibration is an efficient way to improve the accuracy. Previous methods such as using coordinate measurement machines, laser trackers or cameras are limited by the cost, complex operation or the resolution. The purpose of this paper is to propose an approach and calibration equipment to address these issues.
Design/methodology/approach
The proposed method relies mainly upon a laser pointer attached on the end‐effector and single position‐sensitive devices (PSD) arbitrarily located on the workcell. The automated calibration procedure (about three minutes) involves aiming the laser lines loaded by the robot towards the center of the PSD surface from various robot positions and orientations. The localization is guaranteed by precise PSD feedback servoing control, which means physically the intersections of each pair of laser lines (virtual lines) are on the same point. Based on the untouched single‐point constraint, the robot joint offset calibration is implemented. Using the authors' proposed approach, a portable, low‐cost, battery‐powered, wireless and automated calibration system was implemented. Error analysis was conducted on the system.
Findings
The localization error of the developed calibration system is within 2 μm. The errors in joint space are magnified in PSD plane, and consequently the resolution in the joint space is improved. The standard deviation of the identified parameters was small (10‐2), indicating the stability of the calibration method. Both simulation and experimental results verify the feasibility of the proposed method and demonstrate the developed calibration system can identify joint offset with uncalibrated laser tool parameters.
Originality/value
The paper shows how a portable calibration system for joint offset of industrial robots was developed and how the goal of fast, automated, low‐cost, portable, and high precision calibration methods for joint offset was achieved.
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Dalia Marciukaityte and Samuel H. Szewczyk
We examine whether discretionary accruals of firms obtaining substantial external financing can be explained by managerial manipulation or managerial overoptimism. Insider trading…
Abstract
We examine whether discretionary accruals of firms obtaining substantial external financing can be explained by managerial manipulation or managerial overoptimism. Insider trading patterns and press releases around equity and debt financing suggest that managers are more optimistic about their firms around debt financing. Consistent with earlier studies, we find that discretionary current accruals peak when firms obtain equity financing. However, we also find that discretionary accruals peak when firms obtain debt financing. Moreover, discretionary accruals are higher for firms that rely on debt rather than on equity financing. The results are robust to controlling for firm characteristics, excluding small and distressed firms, and using alternative measures of discretionary accruals. These findings support the hypothesis that managerial overoptimism distorts financial statements of firms obtaining external financing.
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M. Yasin, H.A. Rahman, N. Bidin, S.W. Harun and H. Ahmad
The purpose of this paper is to demonstrate a simple design of a fiber optic displacement sensor using a multimode plastic fiber coupler based on reflective intensity modulation…
Abstract
Purpose
The purpose of this paper is to demonstrate a simple design of a fiber optic displacement sensor using a multimode plastic fiber coupler based on reflective intensity modulation technique.
Design/methodology/approach
The performances of this sensor are investigated by correlating the detector output with different light sources, coupling ratios and various real objects with different reflectivity properties namely aluminum, brass and copper. In contrast to the output profile produced by probes with multiple fibers placed adjacently together, this sensor uses only one fiber for sending and receiving the light and therefore only the back slope exists.
Findings
Aluminum exhibit the highest performance among the real objects when coupled with a red He‐Ne laser and a coupling ratio of 50:50 with a sensitivity, linear range, resolution and dynamic range of 1.7 mV/mm, 1.5 mm, 16 μm, and 5.0 mm, respectively.
Originality/value
This is the first demonstration of a fiber optic displacement sensor using fiber coupler probe with successful examination of the correlation between the detector output, variation in coupling ratios and reflectivity properties of the tested real objects.
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Hervé Stolowy and Gaétan Breton
Accounts manipulation has been the subject of research, discussion and even controversy in several countries including the USA, Canada, the U.K., Australia, Finland and France…
Abstract
Accounts manipulation has been the subject of research, discussion and even controversy in several countries including the USA, Canada, the U.K., Australia, Finland and France. The objective of this paper is to provide a comprehensive review of the literature and propose a conceptual framework for accounts manipulation. This framework is based on the possibility of wealth transfer between the different stake‐holders, and in practice, the target of the manipulation appears generally to be the earnings per share and the debt/equity ratio. The paper also describes the different actors involved and their potential gains and losses. We review the literature on the various techniques of accounts manipulation: earnings management, income smoothing, big bath accounting, creative accounting, and window‐dressing. The various definitions of all these, the main motivations behind their application and the research methodologies used are all examined. This study reveals that all the above techniques have common elements, but there are also important differences between them.