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The purpose of this paper is to use the corresponding magnetic sensor and detection method to detect and image the defects of small diameter pipelines. Urban gas pipeline is an energy transportation tool for urban industrial production and social life, which is closely related to urban safety. Preventing the occurrence of urban gas pipeline transportation accidents and carrying out pipeline defect detection are of great significance for the urban economic and social stability. To perform pipeline defect detection, the magnetic flux leakage internal detection method is generally used in the detection of large-diameter long-distance oil and gas pipelines. However, in terms of the internal detection of small-diameter pipelines, due to the heavy weight, large structure of the detection device and small pipe diameter, the detection is more difficult.

In order to solve the above matters, self-made three-dimensional magnetic sensor and three-dimensional magnetic flux leakage imaging direct method are proposed for studying the defect identification. Firstly, for adapting to the diameter range of small-diameter pipelines, and containing the complete information of the defect, a self-made three-dimensional magnetic sensor is made in this paper to improve the accuracy of magnetic flux leakage detection. And on the basis of it, a small diameter pipeline defect detection system is built. Secondly, as detection signal may be affected by background magnetic field interference and the jitter interference, the complete ensemble empirical mode decomposition with adaptive noise method is utilized to screen the detected signal. As a result, the useful signal is reconstructed and the interference signal is removed. Finally, the defect contour inversion imaging of detection is realized based on the direct method of three-dimensional magnetic flux leakage imaging, which includes three-dimensional magnetic flux leakage detection data and data segmentation recognition.

The three-dimensional magnetic flux leakage imaging experimental results shown that, compared to the actual defects, the typical defects, irregular defects and crack groove defects can be analyzed by the magnetic flux leakage defect contour imaging method in qualitative and quantitative way respectively, which provides a new idea for the research of defect recognition.

A three-dimensional magnetic sensor is made to adapt the diameter range of small diameter pipeline, and based on it, a small-diameter pipeline defect detection system is built to collect and display the magnetic flux leakage signal.

The purpose of this paper is to describe how people in a coastal community act upon anxieties about overexploitation of a shared resource and their attempts to ease the moral tension caused by the rapid industrialization of their fishery. This anthropological study contributes to the cross-disciplinary discussion of community-based resource management.

The study is based on ethnographic fieldwork done at the Nanfang'ao port located in northeastern Taiwan. This port has several prosperous offshore fisheries including a mackerel fishery. The mackerel fishery has undergone important transformations in recent decades. The first was a total transformation of fishing methods in 2013. The second was the government's formulation of the “Regulations for Fishing Vessels Catching Mackerels and Jacks,” implemented in 2014. This research illustrates how people in a community take various approaches to pursue sustainability for the human beings and the more-than-human world.

In Nanfang'ao port, local people have developed a meaningful cultural festival through the integration of various symbols and rituals from different contexts in an effort to call attention to moral issues associated with the mackerel fishery.

This research contributes to the discussion on community resource management of marine fishery.

The purpose of this study is to analyse the effect of health risk perceptions on the degree of decisiveness of a person towards e-commerce (e-commerce acceptance), self-awareness towards leisure and self-awareness towards socialisation in pandemic contexts. The identified gap was related to the COVID-19 pandemic, where the development of studies inherent to this context is becoming urgent. Thus, it was necessary to understand how the health risks perceived by individuals influenced their choice regarding online shopping and, simultaneously, socialising and leisure activities.

To reach this goal, a conceptual model was developed based on the self-determination theory, and data were collected from two countries (Portugal and Croatia). The model was estimated using the structural equation modelling (SEM).

The results showed that the perceptions regarding health risks have a positive effect on the degree of decisiveness of a person towards e-commerce acceptance and self-awareness towards socialisation. In turn, the perceptions of health risks have a positive effect on self-awareness towards leisure, not supporting the model conceptualisation.

The paper contributes to fill a gap in literature by analysing the simultaneous effect of individuals’ e-commerce motivations for leisure and socialising activities within a pandemic context. These results have significant managerial implications for several stakeholders that must communicate to the specific public regarding this type of events.

El propósito de este estudio es analizar el efecto de las percepciones de riesgo para la salud sobre i) el grado de decisión de una persona hacia el comercio electrónico (aceptación del comercio electrónico); ii) la autoconciencia hacia el ocio; y iii) la autoconciencia hacia la socialización en contextos de pandemia. La laguna identificada estaba relacionada con la pandemia de COVID-19, donde era urgente desarrollar estudios inherentes a este contexto. Así, era necesario comprender cómo los riesgos para la salud percibidos por los individuos influían en su elección respecto a las compras en línea y, simultáneamente, a las actividades de socialización y ocio.

Para alcanzar este objetivo, se desarrolló un modelo conceptual, basado en la teoría de la autodeterminación y se recogieron datos de dos países (Portugal y Croacia). El modelo se estimó mediante un modelo de ecuaciones estructurales (SEM).

Los resultados mostraron que las percepciones sobre los riesgos para la salud tienen un efecto positivo en el grado de decisión de una persona hacia la aceptación del comercio electrónico y la autoconciencia hacia la socialización. A su vez, las percepciones sobre los riesgos para la salud tienen efectos positivos sobre la autoconciencia hacia el ocio no suportando la conceptualización del modelo.

El artículo contribuye a llenar un vacío en la literatura al analizar el efecto simultáneo de las motivaciones de comercio electrónico de los individuos para actividades de ocio y socialización en un contexto de pandemia. Estos resultados tienen importantes implicaciones de gestión para varios actores que deben comunicar al público específico sobre el tipo de eventos.

O objetivo deste estudo é analisar o efeito da perceção dos riscos para a saúde sobre i) o grau de decisão de uma pessoa em relação ao comércio eletrónico (aceitação do comércio eletrónico); ii) a auto-consciencialização em relação ao lazer; e iii) a auto-consciencialização em relação à socialização em contextos pandémicos. A lacuna identificada estava relacionada com a pandemia da COVID-19, onde era urgente desenvolver estudos inerentes a este contexto. Assim, foi necessário compreender como os riscos de saúde percebidos pelos indivíduos influenciaram a sua escolha relativamente às compras on-line e, simultaneamente, às atividades de socialização e lazer.

Para atingir este objetivo, foi desenvolvido um modelo concetual, com base na teoria da autodeterminação e foram recolhidos dados de dois países (Portugal e Croácia). O modelo foi estimado utilizando a modelação de equações estruturais (SEM).

Os resultados mostraram que as perceções relativas aos riscos de saúde têm um efeito positivo sobre o grau de decisão de uma pessoa em relação à aceitação do comércio eletrónico e de auto-consciencialização em relação à socialização. Por sua vez, as perceções dos riscos de saúde têm efeitos positivos sobre a auto-consciencialização em relação ao lazer não suportando o modelo concetual.

O artigo contribui para preencher uma lacuna na literatura ao analisar o efeito simultâneo das motivações do comércio eletrónico dos indivíduos para atividades de lazer e socialização em um contexto de pandemia. Estes resultados têm implicações de gestão significativas para vários intervenientes que devem comunicar ao público específico sobre o tipo de eventos.

The purpose of this paper is to provide an automatic parallelization toolkit for unstructured mesh-based computation. Among all kinds of mesh types, unstructured meshes are dominant in engineering simulation scenarios and play an essential role in scientific computations for their geometrical flexibility. However, the high-fidelity applications based on unstructured grids are still time-consuming, no matter for programming or running.

This study develops an efficient UNstructured Acceleration Toolkit (UNAT), which provides friendly high-level programming interfaces and elaborates lower level implementation on the target hardware to get nearly hand-optimized performance. At the present state, two efficient strategies, a multi-level blocks method and a row-subsections method, are designed and implemented on Sunway architecture. Random memory access and write–write conflict issues of unstructured meshes have been handled by partitioning, coloring and other hardware-specific techniques. Moreover, a data-reuse mechanism is developed to increase the computational intensity and alleviate the memory bandwidth bottleneck.

The authors select sparse matrix-vector multiplication as a performance benchmark of UNAT across different data layouts and different matrix formats. Experimental results show that the speed-ups reach up to 26× compared to single management processing element, and the utilization ratio tests indicate the capability of achieving nearly hand-optimized performance. Finally, the authors adopt UNAT to accelerate a well-tuned unstructured solver and obtain speed-ups of 19× and 10× on average for main kernels and overall solver, respectively.

The authors design an unstructured mesh toolkit, UNAT, to link the hardware and numerical algorithm, and then, engineers can focus on the algorithms and solvers rather than the parallel implementation. For the many-core processor SW26010 of the fastest supercomputer in China, UNAT yields up to 26× speed-ups and achieves nearly hand-optimized performance.

Mobile devices have received much research interest in recent years. Mobility raises new issues such as more dynamic context, limited computing resources, and frequent disconnections. A middleware infrastructure for mobile computing must handle all these issues properly. In this project we propose a middleware, called 3DMA, to support mobile computing. We introduce three requirements, distribution, decoupling and decomposition as central issues for mobile middleware. 3DMA uses a space based middleware, which facilitates the implementation of decoupled behavior and support for disconnected operation and context awareness. This is done by defining a set of “workers” which are able to act on the users behalf either: to reduce load on the mobile device, and/or to support disconnected behavior. In order to demonstrate aspects of the middleware architecture we then consider the development of a commonly used mobile application.

Achieving a zero-carbon city requires a long-term strategic perspective. The authors propose a decision-making model which would take into account the economic, environmental and social impacts for prioritizing the zero-carbon measures for sustainable urban transportation.

An integrated intuitionistic fuzzy gained and lost dominance score (IF-GLDS) model is introduced based on intuitionistic fuzzy Yager weighted aggregation (IFYWA) operators and proposed weight-determining IF-SPC procedure. In addition, a weighting tool is presented to obtain the weights of decision experts. Further, the feasibility and efficacy of developed IF-SPC-GLDS model is implemented on a multi-criteria investment company selection problem under IFS context.

The results of the developed model, “introducing zero-emission zones” should be considered as the first measure to implement. The preference of this initiative offers sustainable transport in India to achieve a zero-carbon transport by having the greatest impact on the modal shift from cars to sustainable mobility modes with a lower operational and implementation cost as well as having greater public support. The developed model utilized can be relocated to other smart cities which aim to achieve a zero-carbon transport. Sensitivity and comparative analyses are discussed to reveal the robustness of obtained result. The outcomes show the feasibility of the developed methodology which yields second company as the suitable choice, when compared to and validated using the other MCDA methods from the literature, including TOPSIS, COPRAS, WASPAS and CoCoSo with intuitionistic fuzzy information.

A new intuitionistic fuzzy symmetry point of criterion (IF-SPC) approach is presented to find weights of criteria under IFSs setting. Then, an IF-GLDS model is introduced using IFYWA operators to rank the options in the realistic multi-criteria decision analysis (MCDA) procedure. For this purpose, the IFYWA operators and their properties are developed to combine the IFNs. These operators can offer a flexible way to deal with the realistic MCDA problems with IFS context.

In 2011, the new Arbitration Ordinance took effect in Hong Kong. This paper aims to discuss the new features on maritime arbitration.

The relevant provisions of the Arbitration Ordinance 2011 and the legal cases are examined.

Hong Kong is a first class maritime arbitration centre in the Asia Pacific Region.

This paper is one of the very few general reviews of the maritime arbitration under the Arbitration Ordinance 2011.

After‐tax income distributions in the UK for a period of 12 years have been used for estimating the coefficient of inequality‐aversion ε implicit in the income distributions, the change in ε during the period, as well as Atkinson's index of inequality corresponding to the different ε. The method used is non‐linear regression analysis.

The density and pattern of urban parks, traffic conditions are the main factors affecting urban park accessibility. To clarify the influence of traffic mode and urban road network on urban park accessibility, we examine downtown area of Nanjing, China, and based on GIS network analysis, analyze urban park accessibility under different traffic modes in the current year (2017) and the Nanjing master planning target year (2030). The results shows: Using automobiles takes the shortest time to get to urban parks in 2017 and 2030 (if the problem of parking is ignored). Comparing the results of 2030 and 2017, by when the ground transportation network in the study area will be further improved, urban park accessibility was improved by a small margin under walking and automobile traffic modes, however, the density of rail traits increased fastest, urban park accessibility is improved most under this mode of transportation, rail transit route development becomes the dominant factor in improving park accessibility in downtown area of Nanjing. To a certain extent, this study reveals the leading factors of improving the accessibility of urban parks on the premise that the system of urban parks tends to be stable, and provides a reference for improving urban park accessibility.

On account of the flexibility, large working space and system openness, manipulators are often adopted in automatic grinding and polishing operations. In the flexible roboticized polishing process for complex surfaces with narrow spatial structures, such as aero-engine blades, the contact mode between the tool and the workpiece changes with the transformation of the manipulator’s end posture and the alternation of the workpiece curvature, which often leads to processing contact faults. These faults result in the obsolescence of expensive aerospace components and reduced efficiency. The purpose of this study is to collect vibration signals during the machining process and extract fault characteristic parameters for monitoring and diagnosis for diagnosing faults in automated flexible polishing to protect the workpiece.

This paper proposes a whale optimization algorithm (WAO)-support vector machine model based on the support vector machine and WAO. From the original grinding and polishing vibration signal, 11 time-domain features that can reflect the fluctuation of the vibration signal are extracted as detection features.

Experimental results indicate that this method effectively reflects the relationship between contact faults and diagnostic results, demonstrating good real-time performance and diagnostic capability.

This method provides a crucial theoretical basis for real-time fault diagnosis and monitoring in automatic flexible machining, ensuring reliable automatic flexible polishing processes.