Smart cities offer services to their inhabitants which make everyday life easier beyond providing a feedback channel to the city administration. For instance, a live timetable service for public transportation or real-time traffic jam notification can increase the efficiency of travel planning substantially. Traditionally, the implementation of these smart city services require the deployment of some costly sensing and tracking infrastructure. As an alternative, the crowd of inhabitants can be involved in data collection via their mobile devices. This emerging paradigm is called mobile crowd-sensing or participatory sensing. In this paper, we present our generic framework built upon XMPP (Extensible Messaging and Presence Protocol) for mobile participatory sensing based smart city applications. After giving a short description of this framework we show three use-case smart city application scenarios, namely a live transit feed service, a soccer intelligence agency service and a smart campus application, which are currently under development on top of our framework.
In this paper we introduce a public transit schedule and route planner application for urban public transportation. The application was developed for the Android Operating System. It works offline and does not need a permanent internet connection.While transport agencies usually make their schedules available online, browsing them outdoors is not always possible, or requires too much effort on the small screen of a mobile phone. The solutions of this problem are the GTFS databases, which describe the urban public transportation systems. Developers can create applications which use the GTFS databases. However, these databases are not applicable for fast processing needed for route planning on mobile devices with limited resources. Therefore we created a data structure from the GTFS database which is easier to manage, smaller and faster to process. The Android application uses this data structure.The application lists the departure times, journey times and the stops of the lines. It can display the lines on the map. It also shows the stops nearby with the name of the lines passing through. The user can choose one or more stops and view details about the lines passing through.The main function of the application is the route planner. It plans at least one route from a starting-point to a destination. Before the route planning the user can set parameters which are taken into account by the route planner.
The OPTICS algorithm is a hierarchical density-based clustering method. It creates reachability plots to identify all clusters in the point set.Nevertheless, it has limitation, namely it is very slow for large data sets. We introduce the GridOPTICS algorithm, which builds a grid structure to reduce the number of data points, then it applies the OPTICS clustering algorithm on the grid structure. In order to get the clusters, the algorithm uses the reachability plots of the grid structure, then it determines to which cluster the original input points belong. The experimental results show that our new algorithm is faster than the OPTICS, the speed-up can be one or two orders of magnitude or more, which depends mainly on the τ parameter of the GridOPTICS algorithm. At the end of the article, we give some advice to which point set you can apply the GridOPTICS algorithm.
The Not Structured Query Language (NoSQL) databases have become more relevant to applications developers as the need for scalable and flexible data storage for online applications has increased. Each NoSQL database system provides features that fit particular types of applications. Thus, the developer must carefully select according to the application's needs. Redis is a key-value NoSQL database that provides fast data access. On the other hand, the Apache HBase database is a column-oriented database that offers scalability and fast data access, is a promising alternative to Redis in some types of applications. In this research paper, the goal is to use the Yahoo Cloud Serving Benchmark (YCSB) to compare the performance of two databases (Redis and HBase). The YCSB platform has been developed to determine the throughput of both databases against different workloads. This paper evaluates these NoSQL databases with six workloads and varying threads.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.