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This paper aims to propose a robotic automation system for processing special-shaped thin-walled workpieces, which includes a measurement part and a processing part.

In the measurement part, to efficiently and accurately realize the three-dimensional camera hand-eye calibration based on a large amount of measurement data, this paper improves the traditional probabilistic method. To solve the problem of time-consuming in the extraction of point cloud features, this paper proposes a point cloud feature extraction method based on seed points. In the processing part, the authors design a new type of chamfering tool. During the process, the robot adopts admittance control to perform compensation according to the feedback of four sensors mounted on the tool.

Experiments show that the proposed system can make the tool smoothly fit the chamfered edge during processing and the machined chamfer meets the processing requirements of 0.5 × 0.5 to 0.9 × 0.9 mm².

The proposed design and approach can be applied on many types of special-shaped thin-walled parts. This will give a new solution for the automation integration problem in aerospace manufacturing.

A novel robotic automation system for processing special-shaped thin-walled workpieces is proposed and a new type of chamfering tool is designed. Furthermore, a more accurate probabilistic hand-eye calibration method and a more efficient point cloud extraction method are proposed, which are suitable for this system when comparing with the traditional methods.

The purpose of this paper is to use a simple method to enhance the ability of lower limb exoskeletons to restore balance under large interference conditions and to solve the problem that biped robot stability criterion cannot be fully applied to the underactuated lower limb exoskeletons.

The method used in this paper is to construct an underactuated lower extremity exoskeleton ankle joint with a torsion spring. Based on the constructed exoskeleton, the linear inverted torsion spring pendulum model is proposed, and the traditional capture point (CP) concept is optimized.

The underactuated exoskeleton ankle joint with torsion springs, combined with the improved CP concept, can effectively reduce the forward stepping distance under the same interference condition, which is equivalent to enhancing the balance ability of the lower extremity exoskeleton.

The contribution of this paper is to enhance the balance ability of the exoskeleton of the lower limbs under large interference conditions. The torsion spring is used as the exoskeleton ankle joint, and the traditional CP concept is optimized according to the constructed exoskeleton.

To circumvent the high computational costs of modelling each lamination to compute the eddy current distribution in three dimensions in conducting laminations, a simple method has been developed. The laminar nature of the eddy currents due to the magnetic leakage field has been considered by applying an anisotropic conductivity with zero or very low value in the direction normal to the laminations. This yields an overall field distribution serving as basis. In a second step, the much smaller eddy current loops caused by the main magnetic flux parallel to the laminations have been taken into consideration by a one‐dimensional analytical model. Nonlinearity is neglected.

The purpose of this study is to generate diversified results for temporally ambiguous queries and the candidate queries are ensured to have a high coverage of subtopics, which are derived from different temporal periods.

Two novel time-aware query suggestion diversification models are developed by integrating semantics and temporality information involved in queries into two state-of-the-art explicit diversification algorithms (i.e. IA-select and xQuaD), respectively, and then specifying the components on which these two models rely on. Most importantly, first explored is how to explicitly determine query subtopics for each unique query from the query log or clicked documents and then modeling the subtopics into query suggestion diversification. The discussion on how to mine temporal intent behind a query from query log is also followed. Finally, to verify the effectiveness of the proposal, experiments on a real-world query log are conducted.

Preliminary experiments demonstrate that the proposed method can significantly outperform the existing state-of-the-art methods in terms of producing the candidate query suggestion for temporally ambiguous queries.

This study reports the first attempt to generate query suggestions indicating diverse interested time points to the temporally ambiguous (input) queries. The research will be useful in enhancing users’ search experience through helping them to formulate accurate queries for their search tasks. In addition, the approaches investigated in the paper are general enough to be used in many domains; that is, experimental information retrieval systems, Web search engines, document archives and digital libraries.

The paper analyzes the impact of bank opacity on financial stability in an emerging economy.

Based on a unique dataset of 31 Vietnamese commercial banks from 2007 to 2019, the paper captures earnings opacity via discretionary loan loss provisions and reflects individual bank stability through the accounting-based Z-score index and its disaggregate components. The least squares dummy variable corrected (LSDVC) approach is employed for empirical analysis.

In contradiction to most studies on developed economies, earnings management improves bank financial stability in Vietnam. Earnings management is more important for the financial stability of smaller banks. Further, the effect of financial information disclosure on bank stability is strengthened by unfavorable macroeconomic conditions, particularly economic downturns, the global financial crisis and uncertain times in banking.

This is the first study to shed light on how bank opacity influences bank financial stability in an emerging market. The evidence with the conditioning roles of bank size and macroeconomic factors, such as uncertainty in banking, is entirely novel in the related literature. Additionally, the paper contributes to a growing body of banking literature by using the LSDVC estimator to examine the association between bank opacity and bank stability.

Lower extremity exoskeletons have drawn much attention recently due to their potential ability to help the stroke and spinal cord injury patients to regain the ability of walking. However, the balance of the human-exoskeleton system (HES) remains a big challenge. Usually, patients use crutches to keep balance when they wear exoskeleton. However, the balance depends greatly on the patient's balance ability and will be inevitably poor occasionally, which often causes the landing in advance of HES. The purpose of this paper is to propose a real-time stepping gait trajectory planning method based on the hip height variation of the swing leg to solve the problem.

The hip height of the swing leg was analyzed and measured. The simulation with MATLAB and the experimental test with the prototype of the proposed gait were conducted to verify its feasibility.

With the proposed method, HES can achieve successful step even when the balance kept by crutches is poor.

Instead of actively avoiding the poor balance due to the instability caused by gravity, the method just modifies the stepping gait passively to avoid the landing in advance when the poor balance appears. In addition, it may not work well when the balance is too poor. Moreover, the proposed gait is just used in the initial stage of rehabilitation training. Besides, the step length of the gait must be limited for comfort.

A real-time stepping gait trajectory planning method based on the hip height variation of the swing leg is first proposed and its feasibility to avoid the landing in advance when the balance kept by the crutches is poor has been preliminary verified.

The current era of the fourth industrial revolution has attracted significant research on the use of digital technologies in improving construction project delivery. However, less emphasis has been placed on how these digital tools will influence the management of the construction workforce. To this end, using a review of existing works, this chapter explores the fourth industrial revolution and its associated technologies that can positively impact the management of the construction workforce when implemented. Also, the possible challenges that might truncate the successful deployment of digital technologies for effective workforce management were explored. The chapter submitted that implementing workforce management-specific digital platforms and other digital technologies designed for project delivery can aid effective workforce management within construction organisations. Technologies such as cloud computing, the Internet of Things, big data analytics, robotics and automation, and artificial intelligence, among others, offer significant benefits to the effective workforce management of construction organisations. However, several challenges, such as resistance to change due to fear of job loss, cost of investment in digital tools, organisational structure and culture, must be carefully considered as they might affect the successful use of digital tools and by extension, impact the success of workforce management in the organisations.

A mathematical model has been developed to predict steady state creep response of a rotating disc made of SiC (particle/whisker) reinforced 6061Al matrix composite. The model is used to investigate the effect of SiC morphology on the creep behavior of composite disc. The steady state creep behavior has been described by Sherby’s creep law. The creep stresses and creep rates are significantly affected by the morphology of SiC. The steady state creep rates in whisker reinforced disc are observed to be significantly lower than those observed in particle reinforced disc.

This paper provides a quantitative review of the literature on the repercussions of idiosyncratic information on firms’ cost of equity (CoE) capital. In total, I review the results of 113 unique studies examining the CoE effects of information Quantity, Precision and Asymmetry. My results suggest that the association between firm-specific information and CoE is subject to moderate effects. First, the link between Quantity and CoE is moderated by disclosure types and country-level factors in that firms in comparatively weakly regulated countries tend to enjoy up to four times greater CoE benefits from more expansive disclosure—depending on the type of disclosure—than firms in strongly regulated markets. Second, a negative relationship between Precision and CoE is only significant in studies using non-accrual quality proxies for Precision and risk factor-based (RFB)/valuation model-based (VMB) proxies for CoE. Third, almost all VMB studies confirm the positive association between Asymmetry and CoE, but there is notable variation in the conclusions reached when ex post CoE measurers are used.

This paper analyses the development, regulation and future trend of the corporate insurance market in the People’s Republic of China (PRC). Using data for 212 Chinese listed companies over the period 1997‐99, this study provides some preliminary empirical evidence regarding the property insuring behaviour of Chinese companies. I find that the level of property insurance spending in Chinese companies is inversely related to company size and leverage. Additionally, the purchase of property insurance appears to vary according to geographical location and industry sectors. However, foreign ownership does not appear to have important influences on the managerial property insurance decisions in the Chinese corporate sector. The findings of this study could thus have important implications for various groups (e.g., corporate lenders and foreign insurers) that are interested in the Chinese corporate sector and insurance markets.