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The purpose of this paper is to introduce an expressive query language, called relational XML query language (RXQL), capable of dealing with heterogeneous Extensible Markup Language (XML) documents in data‐centric applications. In RXQL, data harmonization (i.e. the removal of heterogeneous factors from XML data) is integrated with typical data‐centric features (e.g. grouping, ordering, and aggregation).

RXQL is based on the XML relation representation, developed in the authors' previous work. This is a novel approach to unambiguously represent semistructured data relationally, which makes it possible in RXQL to manipulate XML data in a tuple‐oriented way, while XML data are typically manipulated in a path‐oriented way.

The user is able to describe the result of an RXQL query straightforwardly based on non‐XML syntax. The analysis of this description, through the mechanism developed in this paper, affords the automatic construction of the query result. This feature increases significantly the declarativeness of RXQL compared to the path‐oriented XML languages where the user needs to control the construction of the result extensively.

The authors' formal specification of the construction of the query result can be considered as an abstract implementation of RXQL.

RXQL is a declarative query language capable of integrating data harmonization seamlessly with other data‐centric features in the manipulation of heterogeneous XML data. So far, these kinds of XML query languages have been missing. Obviously, the expressive power of RXQL can be achieved by computationally complete XML languages, such as XQuery. However, these are not actual query languages, and the query formulation in them usually presupposes programming skills that are beyond the ordinary end‐user.

The purpose of this paper is to develop a portable all‐position welding robot for the welding of intersected pipes.

A complete procedure is adopted to conduct the design. The task and motion of the robot are analyzed and a mathematical description of the pose and position of the welding tool is given. Based on that, three representative types of robot are chosen in the type synthesis of mechanism. Two new indices proposed to evaluate required properties of the robot, along with the traditional dexterity index, are chosen to be the criteria in the dimension synthesis of mechanism. Through the optimization by genetic algorithm, the best robot in type and dimension is determined after comparison on their performances. Finally, the prototype is developed.

The paper finds a new robot for welding intersected pipes.

A new robot is introduced for the welding of intersected pipes. A complete design procedure is adopted to conduct the design. Two new indices are constructed for evaluating the required properties of this robot.

In a widely‐publicised article in Business Week magazine, three American journalists pose the rhetorical question ‘What's wrong with the Internet?’, and give three pithy responses with the intention of summarising the opinion of millions of network users around the world. Firstly, they argue, ‘it's too slow’: people are fed up with the ‘World Wide Wait’. Secondly, ‘it's not built right’: security is poor, support for multimedia is weak, and charging for usage is problematic. And thirdly, ‘good stuff is hard to find’: a commonly quoted aphorism characterises the Internet as a library where the shelves keep moving, where there is no catalogue, and where an extra lorry‐load of books is dumped in the entrance hall every five minutes.

This study aims to investigate the coordinated impact of regulations on the predicted probability of a banking crisis in Africa.

The study used the dynamic panel instrumental variable probit regression model of 52 African economies over the period 2006 to 2018.

The authors observe that banking crisis is persistent for few years but dissipates in the long run. The results show that board mechanism and ownership control are important in reducing the likelihood of banking crisis. The authors found a negative impact of regulatory capital and monetary policy on the predicted probability of a banking crisis while regulatory quality was not strong in reducing the likelihood of banking crisis. There was also evidence to support that regulatory capital and monetary policy augment the negative impact of board mechanism and ownership control on the predicted probability of a banking crisis.

The limitation of the study is that it did not explore all measures of regulatory framework and how they impact banking crisis. However, it has an advantage of using alternative measures of regulations in a banking crisis probability model. Therefore, future studies should include other macro-prudential regulations, regulatory environments and supervision and observe how they are coordinated to reduce possible crisis in a robust methodological framework.

The research has policy implications for monetary authorities and policymakers to set coordinated regulations through internal banking mechanisms that are relevant in sustaining banking system stability goals. Countries in Africa should strengthen their quality of regulation in such a way that it can play a strong and complementary role to a robust internal control mechanisms, so as to maintain stability in the banking system. In general, regulators and policymakers should design greater coordination of external and internal regulations through a single regulatory framework and a common resolution mechanism that make the banking system more robust in curbing possible crisis.

The policy implication of the study is to build banking confidence in the society.

This study analyses the interactions of different components of internal and external regulatory framework in helping to reduce the probability of a banking crisis in Africa.

A survey of current work on database systems is presented. The area is divided into three main sectors: data models, data languages and support for database operations. Data models are presented as the link between the database and the real world. Languages range from formal algebraic languages to attempts to use a dialogue in English to formulate queries. The support includes hardware for content addressing, database machines and software techniques for optimizing and evaluating group expressions. Mathematical models are used to organize this support. Throughout there is a tutorial component and evaluation, which in both cases is related to the application of database ideas to documentation.

Examines the issue of uprating the minimum wage. Argues that this issue is nearly as important as the level of the minimum wage, but one that has been relatively neglected. Maintains that Britain lacks an adequate uprating mechanism and outlines some consequences of this. Argues that increases in the UK have had an erratic pattern that may be related to the electoral cycle. Drawing upon experience in the USA, argues that the lack of an adequate mechanism may lead to: avoidable and intense political lobbying; greater instability and uncertainty for low paying firms; and unfairness to those on or near minimum wages, who are then held captive to the vagaries of the political process to maintain the value of their incomes. Considers the possible form of any uprating mechanism with an overview of the US and French experience. Argues that any uprating mechanism must not only maintain the value of the minimum wage in relation to inflation but also to those of more highly paid workers.

The coupling impact of hybrid uncertain errors on the machine precision is complex, as a result of which the designing method with multiple independent error sources under uncertainties remains a challenge. For the purpose of precision improvement, this paper focuses on the robot design and aims to present an assembly precision design method based on uncertain hybrid tolerance allocation (UHTA), to improve the positioning precision of the mechanized robot, as well as realize high precision positioning within the workspace.

The fundamentals of the parallel mechanism are introduced first to implement concept design of a 3-R(4S) &3-SS parallel robot. The kinematic modeling of the robot is carried out, and the performance indexes of the robot are calculated via Jacobian matrix, on the basis of which, the 3D spatial overall workspace can be quantified and visualized, under the constraints of limited rod, to avoid the singular position. The error of the robot is described, and a probabilistic error model is hereby developed to classify the hybrid error sensitivity of each independent uncertain error source by Monte Carlo stochastic method. Most innovatively, a methodology called UHTA is proposed to optimize the robot precision, and the tolerance allocation approach is conducted to reduce the overall error amplitude and improve the robotized positioning precision, on the premise of not increasing assembly cost.

The proposed approach is validated by digital simulation of medical puncture robot. The experiment highlights the mathematical findings that the horizontal plane positioning error of the parallel robotic mechanism can be effectively reduced after using UHTA, and the average precision can be improved by up to 39.54%.

The originality lies in UHTA-based precision design method for parallel robots. The proposed method has widely expanding application scenarios in industrial robots, biomedical robots and other assembly automation fields.

This paper aims to explore the impact of business environment on high-quality economic development (HQED) and clarify the role of technological innovation and government intervention in this relationship.

Based on China’s provincial panel data from 2010 to 2019, this paper adopts the system generalized method of moments to empirically analyze the influential mechanism and heterogeneity of the business environment on HQED. Furthermore, the authors construct a dynamic panel threshold model to test the threshold effect of government intervention.

The results indicate that optimizing the business environment can significantly promote HQED, technological innovation plays a partial mediating role in the impact of business environment on HQED, mainly by enhancing the intensity of innovation input and increasing innovation output to facilitate HQED. Government intervention can regulate the impact of business environment on HQED, and there is a double threshold effect, and it possesses an inverted U-shaped feature of first promoting and then inhibiting.

This paper examines the influence path of business environment on HQED from the perspective of technological innovation and government intervention, filling the gap in the study of provincial business environment. Moreover, the conclusions furnish a theoretical basis for optimizing the business environment and facilitating the HQED in China.