User surveys are essential to user-centered research in many fields, including human-computer interaction (HCI). Survey personalization—specifically, adapting questionnaires the respondents' profiles and experiences—can improve reliability quality of responses. However, popular survey platforms lack usable mechanisms for seamlessly importing participants' data from other systems. This paper explores design a data-driven system fill this gap. First, we conducted formative research, literature...

Web developers can (and do) include subresources such as scripts, stylesheets and images in their webpages. Such might be stored on content delivery networks (CDNs). This practice creates security privacy risks, should a subresource corrupted. The integrity (SRI) recommendation, released mid-2016 by the W3C, enables to digests webpages order for web browsers verify of before loading them. In this paper, we conduct first large-scale longitudinal study use SRI analyzing massive crawls (≈ 3B...

We put forth a system, to predict distant-future positions of multiple moving entities and index the forecasted trajectories, in order answer predictive queries involving long time horizons. Today, proliferation mobile devices with GPS functionality internet connectivity has led rapid development location-based services, accounting for user mobility prediction as key paradigm. Mobility is already playing major role traffic management, urban planning advertising, which demand accurate horizon...

The proliferation of mobile devices equipped with internet connectivity and global positioning functionality (GPS) has resulted in the generation large volumes spatiotemporal data. This led to rapid evolution location-based services. anticipatory nature these services, demand exploitation a broader range user information for service personalization. Determining users' places interest, i.e. hotspots is critical understand their behaviors preferences. Existing techniques detect rely on set...

We are witnessing a rapid proliferation of location-based services, due to the useful context-aware services they provide their users. However, sharing sensitive location traces with untrusted service-providers has many privacy implications. Although, user-data monetization is core economic model such offering private concerned users will be beneficial functionality in coming years. Existing solutions include perturbation, k-anonymity and cryptographic primitives that trade service accuracy...

Data deduplication techniques are often used by cloud storage systems to reduce network bandwidth and requirements. As a consequence, the current research literature tends focus most of its algorithmic efforts on improving Duplicate Elimination Ratio (DER), which reflects compression achieved using given algorithm. Yet, importance this indicator be overestimated, while another key indicator, namely throughput, underestimated. To substantiate claim, we reimplement selection popular...

With billions of connected users and objects, location-based services face a massive scalability challenge. We propose horizontally-scalable reliable publish/subscribe architecture that can be deployed on cluster made commodity hardware. As many modern systems, our supports moving publishers, as well subscribers. When publication moves in the range subscription, owner this subscription is instantly notified via server-initiated event, usually form push notification. To achieve this, most...

Internet users can download software for their computers from app stores (e.g., Mac App Store and Windows Store) or other sources, such as the developers' websites. Most in US rely on latter, according to our representative study, which makes them directly responsible content they download. To enable detect if downloaded files have been corrupted, developers publish a checksum together with link program file; then manually verify that matches one obtain file. In this paper, we assess...

Rich human mobility datasets are fundamental for evaluating algorithms pertaining to geographic information systems. Unfortunately, existing datasets--that available the research community--are restricted location data captured through a single sensor (typically GPS) and have low spatiotemporal granularity. They also lack ground-truth regarding points of interest associated semantic labels (e.g., "home", "work", etc.). In this paper, we present Breadcrumbs, rich dataset collected from...

The rise of the Internet things (IoT) poses massive scalability issues for location-based services. More particularly, location-aware publish and subscribe services are struggling to scale out computation matches between publications subscriptions that continuously update their location. In this demonstration paper, we propose a novel distributed horizontally scalable architecture subscribe. Our middleware relies on multi-step routing mechanism based consistent hashing range partitioning. To...

Finding trajectories and discovering motifs that are similar in large datasets is a central problem for wide range of applications. Solutions addressing this usually rely on spatial indexing the computation similarity measure polynomial time. Although effective context sparse trajectory datasets, approach too expensive dense where many potentially match with given query. In paper, we apply fingerprinting, copy-detection mechanism used textual data, to trajectories. To end, fingerprint...

App stores provide access to millions of different programs that users can download on their computers. Developers also make available for websites and host the program files either directly website or third-party platforms, such as mirrors. In latter case, software without any vetting from developers, they should take necessary precautions ensure it is authentic. One way accomplish this check published file’s integrity verification code—the checksum—matches (if provided) downloaded file. To...

In this paper, we present an efficient type-agnostic approach for finding sub-sequences in data, such as text documents or GPS trajectories. Our relies on data deduplication creating inverted index. contrast with existing techniques that split raw sequences of characters arbitrarily, our preserves the semantics original sequence via notion token and can be used to index normalized data. When compared indexing methods preserve operate method increases relevance index, reduces its size...

Rising summer temperatures in Greenland have accelerated the formation of supraglacial lakes. Since these lakes play a significant role ice sheet dynamics and bed lubrication, their continuous monitoring warming Arctic is becoming essential. The 31st ACM SIGSPATIAL competition (GISCUP 2023) aims to automate detection using satellite imagery. In this paper, we present two solutions problem based on image segmentation techniques: DeepLabv3+ model that ranked first, U-Net-based approach fourth....

Sharing location traces with context-aware service providers has privacy implications. Location-privacy preserving mechanisms, such as obfuscation, anonymization and cryptographic primitives, have been shown to impractical utility/privacy tradeoff. Another solution for enhancing user is minimize data sharing by executing the tasks conventionally carried out at providers' end on users' smartphones. Although volume shared untrusted entities significantly reduced, computationally demanding...

In this paper, we present Breadcrumbs, a mobility dataset collected in the city of Lausanne (Switzerland) from multiple mobile phone sensors (GPS, WiFi, Bluetooth) 81 users for duration 12 weeks. Currently available datasets are restricted to geospatial information obtained through single sensor at low spatiotemporal granularities. Furthermore, passively data lacks ground-truth regarding points interest and their semantic labels. These features critical order push possibilities analysis...

Abstract. Map renderers play a crucial role in Web, desktop, and mobile applications. In this context, code portability is common problem, often addressed by maintaining multiple bases: one for theWeb, usually written JavaScript, desktop mobile, C/C++. The maintenance of several bases slows down innovation makes evolution time-consuming. paper, we review existing open-source map renderers, examine how they address identify the downsides current strategies. With proof concept, demonstrate...

Checksums, typically provided on webpages and generated from cryptographic hash functions (e.g., MD5, SHA256) or signature schemes PGP), are commonly used websites to enable users verify that the files they download have not been tampered with when stored possibly untrusted servers. In this paper, we elucidate current practices regarding usage of checksums for web downloads (hash used, visibility validity checksums, type files, etc.), as has mostly overlooked so far. Using a...

Public transport network constitutes for an indispensable part of a city by providing mobility services to the general masses. To improve ease access and reduce infrastructural investments, public authorities often adopt proof payment system. Such system operates eliminating ticket controls when boarding vehicle subjecting travelers random checks affiliated personnel (controllers). Although cost efficient, such promotes free-riders, who deliberately decide evade fares service. A recent...

Sharing location traces with context-aware service providers has privacy implications. Location-privacy preserving mechanisms, such as obfuscation, anonymization and cryptographic primitives, have been shown to impractical utility/privacy tradeoff. Another solution for enhancing user is minimize data sharing by executing the tasks conventionally carried out at providers' end on users' smartphones. Although volume shared untrusted entities significantly reduced, computationally demanding...

Finding trajectories and discovering motifs that are similar in large datasets is a central problem for wide range of applications. Solutions addressing this usually rely on spatial indexing the computation similarity measure polynomial time. Although effective context sparse trajectory datasets, approach too expensive dense where many potentially match with given query. In paper, we apply fingerprinting, copy-detection mechanism used textual data, to trajectories. To end, fingerprint...