Alireza Sahami Shirazi

Location-based crowdsourcing: extending crowdsourcing to the real world

The WWW and the mobile phone have become an essential means for sharing implicitly and explicitly generated information and a communication platform for many people. With the increasing ubiquity of location sensing included in mobile devices we investigate the arising opportunities for mobile crowdsourcing making use of the real world context. In this paper we assess how the idea of user-generated content, web-based crowdsourcing, and mobile electronic coordination can be combined to extend crowdsourcing beyond the digital domain and link it to tasks in the real world. To explore our concept we implemented a crowd-sourcing platform that integrates location as a parameter for distributing tasks to workers. In the paper we describe the concept and design of the platform and discuss the results of two user studies. Overall the findings show that integrating tasks in the physical world is useful and feasible. We observed that (1) mobile workers prefer to pull tasks rather than getting them pushed, (2) requests for pictures were the most favored tasks, and (3) users tended to solve tasks mainly in close proximity to their homes. Based on this, we discuss issues that should be considered during designing mobile crowdsourcing applications.

Real-time nonverbal opinion sharing through mobile phones during sports events

Even with the rise of the World Wide Web, TV has remained the most pervasive entertainment medium and is nowadays often used together with other media, which allow for active participation. The idea of connecting non-collocated TV viewers via telecommunication technologies, referred to as Social TV, has recently received considerable attention. Such systems typically include set-top boxes for supporting collaboration. In this research we investigate if real-time opinion sharing about TV shows through a nonverbal (non-textual) iconic UI on mobile phones is reasonable. For this purpose we developed a mobile app, made it available to a large number of users through the Android Market, and conducted an uncontrolled user study in the wild during the soccer world cup 2010. The results of the study indicate that TV viewers who used the app had more fun and felt more connected to other viewers. We also show that by monitoring this channel it is possible to collect sentiments relevant to the broadcasted content in real-time. The collected data exemplify that the aggregated sentiments correspond to important moments, and hence can be used to generate a summary of the event.

Flashlight interaction: a study on mobile phone interaction techniques with large displays

In this paper, we introduce Flashlight interaction, a new approach to light-based interaction between mobile phones and large screens by using the phone camera flashlight. Using a mobile phone as an interaction device with large screens has been explored in various projects. Mobile phones are enhanced with different sensors and provide opportunities to be used as an interaction device with other devices such as a large display. Our approach supports to set up a private-public display setting and provide simple means for interaction without a wireless connectivity. Our user study results indicate that the interaction is easy to perform and understand due to the direct mapping between the phone movement and the response on the screen.

Already up? using mobile phones to track & share sleep behavior

Users share a lot of personal information with friends, family members, and colleagues via social networks. Surprisingly, some users choose to share their sleeping patterns, perhaps both for awareness as well as a sense of connection to others. Indeed, sharing basic sleep data, whether a person has gone to bed or waking up, informs others about not just ones sleeping routines but also indicates physical state, and reflects a sense of wellness. We present Somnometer, a social alarm clock for mobile phones that helps users to capture and share their sleep patterns. While the sleep rating is obtained from explicit user input, the sleep duration is estimated based on monitoring a users interactions with the app. Observing that many individuals currently utilize their mobile phone as an alarm clock revealed behavioral patterns that we were able to leverage when designing the app. We assess whether it is possible to reliably monitor ones sleep duration using such apps. We further investigate whether providing users with the ability to track their sleep behavior over a long time period can empower them to engage in healthier sleep habits. We hypothesize that sharing sleep information with social networks impacts awareness and connectedness among friends. The result from a controlled study reveals that it is feasible to monitor a users sleep duration based just on her interactions with an alarm clock app on the mobile phone. The results from both an in-the-wild study and a controlled experiment suggest that providing a way for users to track their sleep behaviors increased user awareness of sleep patterns and induced healthier habits. However, we also found that, given the current broadcast nature of existing social networks, users were concerned with sharing their sleep patterns indiscriminately.

Enabling micro-entertainment in vehicles based on context information

People spend a significant amount of time in their cars (US: 86 minutes/day, Europe: 43 minutes/day) while commuting, shopping, or traveling. Hence, the variety of entertainment in the car increases, and many vehicles are already equipped with displays, allowing for watching news, videos, accessing the Internet, or playing games. At the same time, the urbanization caused a massive increase of traffic volume, which led to people spending an ever-increasing amount of their time in front of red traffic lights. An observation of the prevailing forms of entertainment in the car reveals that content such as text, videos, or games are often a mere adaptation of content produced for television, public displays, PCs, or mobile phones and do not adapt to the situation in the car. In this paper we report on a web survey assessing which forms of entertainment and which types of content are considered to be useful for in-car entertainment by drivers. We then introduce an algorithm, which is capable of learning standing times in front of traffic lights based on GPS information only. This, on one hand, allows for providing content of appropriate length, on the other hand, for directing the attention of the driver back to-wards the street at the right time. Finally, we present a prototype implementation and a qualitative evaluation.

Exploring gesture-based interaction techniques in multi-display environments with mobile phones and a multi-touch table

In this paper, we explore the potential of combining shared and interactive displays (e.g. a multi-touch table) with personal devices (e.g. mobile phones) as an important class of heterogeneous multi-display environments. Within six case studies applications and interactions were invented and implemented that utilize the potential of such heterogeneous multi-display environments. We were in particular interested how to design systems that include interaction across different displays and how to manage public and private information in a group setting. One case study, a digital card game, highlights these design challenges. We explore different natural ways of interaction, including touching the table as well as motion gestures with mobile phones. With this application we provide a use case to discuss gestures combining mobile phones with tabletop surfaces, as well as to explore a private-public display setting. First results showed that combining tables and mobile phones provide a suitable and understandable way for interaction in these settings.

Poker surface: combining a multi-touch table and mobile phones in interactive card games

In this paper, we introduce the design and implementation of a digital card game that combines mobile phone gestures and multi-touch tabletop interactions. Conceptually based on interactions in traditional card games, our Poker game application explores different natural ways of interaction, including touching the table as well as tilting, throwing, and shaking a mobile phone. By exemplarily translating traditional gestures into the digital domain, we provide a use case to discuss useful gestures combing mobile phones with tabletop surfaces, as well as to explore a private-public display setting for digital card games at interactive tables. Additionally, the mobile phone provides a tangible feeling similar to physical cards. The preliminary user study showed that users preferred using mobile phones for interaction compared to direct interaction on the multi-touch table.

Insights into layout patterns of mobile user interfaces by an automatic analysis of android apps

Mobile phones recently evolved into smartphones that provide a wide range of services. One aspect that differentiates smartphones from their predecessor is the app model. Users can easily install third party applications from central mobile application stores. In this paper we present a process to gain insights into mobile user interfaces on a large scale. Using the developed process we automatically disassemble and analyze the 400 most popular free Android applications. The results suggest that the complexity of the user interface differs between application categories. Further, we analyze interface layouts to determine the most frequent interface elements and identify combinations of interface widgets. The most common combination that consists of three nested elements covers 5.43% of all interface elements. It is more frequent than progress bars and checkboxes. The ten most frequent patterns together cover 21.13% of all interface elements. They are all more frequent than common widget including radio buttons and spinner. We argue that the combinations identified not only provide insights about current mobile interfaces, but also enable the development of new optimized widgets.

Pick from here!: an interactive mobile cart using in-situ projection for order picking

Order Picking is not only one of the most important but also most mentally demanding and error-prone tasks in the industry. Both stationary and wearable systems have been introduced to facilitate this task. Existing stationary systems are not scalable because of the high cost and wearable systems have issues being accepted by the workers. In this paper, we introduce a mobile camera-projector cart called OrderPickAR, which combines the benefits of both stationary and mobile systems to support order picking through Augmented Reality. Our system dynamically projects in-situ picking information into the storage system and automatically detects when a picking task is done. In a lab study, we compare our system to existing approaches, i.e, Pick-by-Paper, Pick-by-Voice, and Pick-by-Vision. The results show that using the proposed system, order picking is almost twice as fast as other approaches, the error rate is decreased up to 9 times, and mental demands are reduced up to 50%.

Assessing the vulnerability of magnetic gestural authentication to video-based shoulder surfing attacks

Secure user authentication on mobile phones is crucial, as they store highly sensitive information. Common approaches to authenticate a user on a mobile phone are based either on entering a PIN, a password, or drawing a pattern. However, these authentication methods are vulnerable to the shoulder surfing attack. The risk of this attack has increased since means for recording high-resolution videos are cheaply and widely accessible. If the attacker can videotape the authentication process, PINs, passwords, and patterns do not even provide the most basic level of security. In this project, we assessed the vulnerability of a magnetic gestural authentication method to the video-based shoulder surfing attack. We chose a scenario that is favourable to the attack-er. In a real world environment, we videotaped the interactions of four users performing magnetic signatures on a phone, in the presence of HD cameras from four different angles. We then recruited 22 participants and asked them to watch the videos and try to forge the signatures. The results revealed that with a certain threshold, i.e, th=1.67, none of the forging attacks was successful, whereas at this level all eligible login attempts were successfully recognized. The qualitative feedback also indicated that users found the magnetic gestural signature authentication method to be more secure than PIN-based and 2D signature methods.