Interturn short circuit fault of distribution transformer winding occurs frequently and is difficult to accurately real-time monitoring, which seriously affects the reliability of the distribution network power supply. Therefore, the identification method of interturn short circuit faults for distribution transformers based on power loss variation is proposed to realize the online monitoring of winding interturn short circuit faults and early warning of insulation deterioration. First, the “field-circuit” coupling three-dimensional simulation model is established as consistent with the actual transformer. On the premise of verifying the reliability and accuracy of the model, the variation characteristics of each physical quantity are simulated and analyzed when a single-turn short circuit occurs in different positions in the secondary side inner and outer winding of the distribution transformer. The winding power loss with the most significant change rate and easy to detect is obtained as the sensitive state variable. Then, by changing the winding interturn insulation resistance and the number of short-circuit turns, the gradual altering process of interturn insulation deterioration is simulated, and the variation law of winding current and power loss in the main circuit is explored. Moreover, the relationship between the interturn insulation state and influence factors including the critical resistance value of interturn insulation deterioration and insulation collapse, the power loss rate of change is analyzed. Finally, a method of interturn short circuit's fault identification of distribution transformer is proposed, which can diagnose the interturn insulation state of transformer winding in real-time and predict the interturn short-circuit fault.

Smart Parking schemes cannot succeed without the engagement and support of the drivers who may benefit from their use. This study investigates engagement with a Smart Parking service in the London Borough of Westminster. Factors likely to influence the use of Smart Parking services were identified from a literature review and incorporated into an explanatory model comprising 9 factors connected by 16 hypotheses. To test the model, residents of Westminster and visitors to the area were surveyed, resulting in a total of 212 valid responses. The responses were used to test a structural equation model, using confirmatory factor analysis. The results of the analysis indicated that Awareness of the scheme; Perceived Ease of Use; Perceived Usefulness; Cost saving; Perceived Privacy and Perceived Security all had a direct impact on Usage, with Awareness being the most influential factor. The results also highlighted the fact that, despite efforts by Westminster Council to publicise the scheme, 74% of respondents had little awareness of it, suggesting the need for improved publicity.

Aligned with the global trend of smartness, China has invested heavily in over 700 smart city projects across over 500 cities. Hundreds of smart city apps, initiated by local authorities, have so emerged in the daily lives of Chinese citizens, but anecdotal evidence showed that these official apps have many problems and deficiencies. This study captures a snapshot of current development and problems of official smart city apps in China. A total of 333 such apps, together with 15754 comments, were collected, reviewed and analyzed. The results showed that China’s smart city apps fall into three application areas, i.e. smart transportation, smart healthcare, and smart livelihood, of which each provides some promising features and services. However, a range of functional, interface, design, usage and service-related problems were found in these apps. This paper concluded that further to the very efforts on infrastructure and hardware, local authorities in China and worldwide need to pay more attention to smart apps, in order to maximize potential return of their smart city investments.

This study aimed to explore factors affecting continual usage of one-stop smart urban apps, which is the key to realise the vision of smart cities. A questionnaire (involved a total of 578 users/citizens) was carried out to test the research model, which was established based on existing user behavioural theories and recent literature on smart cities. The results, derived from confirmatory factor analysis and structural equation modelling, confirmed that lower costs (measured by cognitive effort and perceived risks), as well as higher “smartness” (measured by output usefulness, output velocity, and the quality of offline services), would lead to better user satisfaction. Moreover, system quality has indirect influence on user satisfaction (i.e. citizens only feel dissatisfied when system pitfalls affect output usefulness and output velocity of smart urban apps), which together with social influence will determine citizens’ continuance usage intention of smart urban apps.