Taslim Arefin Khan

Poster: Infrastructure Independent Indoor Localization for Post-Disaster Rescue Mission

The post-disaster rescue work demands a real-time localization of the trapped workers in factories and industries for rapid evacuation. This real-time localization helps first-responders in targeting survivors by escalating post-disaster rescue work. However, existing literature is yet to address indoor localization in disaster affected settings. In this study, we address this issue and perform a testbed experiment. Our preliminary experimental results suggest that our infrastructure independent indoor localization achieves localizing error as low as 4m in indoor environment using Wi-Fi carried by first-responders.

An Empirical Analysis of Facebook's Free Basics

ACM Reference format: Siddharth Singh, Vedant Nanda, Rijurekha Sen, Sohaib Ahmad, Satadal Sengupta, Amreesh Phokeer, Zaid Ahmed Farooq, Taslim Arefin Khan, Ponnurangam Kumaraguru, Ihsan Ayyub Qazi, David Choffnes, and Krishna P. Gummadi. 2017. An Empirical Analysis of Facebook’s Free Basics Program. In Proceedings of ACM Sigmetrics conference, Urbana-Champaign,IL, USA, June 05-09, 2017 (SIGMETRICS ’17), 2 pages. https://doi.org/http://dx.doi.org/10.1145/3078505.3078554

EyePen: Ease of Reading for Less-Privileged Visually-Impaired People

People with visual impairment use Braille as a medium of textual representation having palpable dots. While the more privileged among us use OCR based text readers as preferential alternative, the lesser privileged ones are still bundling with conventional Braille tools. Our endeavor in this paper is to develop a low-cost and easy-to-use solution for less-privileged people. Here, we propose EyePen, a system that enables less-privileged visually-impaired people reading Braille characters, printed using conventional ink-jet and laser printers. The use of printed Braille characters using ink-jet printers offers a cost-effective alternative in place of the more expensively printed conventional palpable Braille dots. Besides, EyePen demands a very short learning period and offers a smooth learning experience ensuring ease-of-use while being in operation. We perform user evaluation over our developed system to confirm these findings. The user evaluation results show that the accuracy of reading printed Braille characters using EyePen converges to 100% within a very short period of time for all users. Finally, we present a potential writing aid that can facilitate low-cost and easy writing of Braille characters on normal paper exploiting our system.

Can You Get into the Middle of Near Field Communication

A recent development emanating from the widely used RFID technology is Near Field Communication (NFC). Basically, NFC is a popular short range (

Sparse mat: A tale of devising a low-cost directional system for pedestrian counting

Pedestrian counting is required in diversified places such as shopping malls, touristic spots, etc., however, a low-cost solution to this problem is yet to be proposed in the literature. Therefore, in this paper, we propose a new solution for pedestrian counting that exploits only a small number of COTS sensors (94% less than that used in the existing Eco-Counter [1] solution). To do so, we propose detail designs and two different algorithms for separately sensing step-down and step-up phenomena that we find while walking. User evaluation of real implementations of both our algorithms confirms an average accuracy of up to 93% through sensing the step-up phenomena.

FLight: A Low-Cost Reading and Writing System for Economically Less-Privileged Visually-Impaired People Exploiting Ink-based Braille System

Reading printed documents and writing on a paper pose a great challenge for visually-impaired people. Existing studies that attempt to solve these challenges are expensive and not feasible in low-income context. Moreover, these studies solve reading and writing problems separately. On the contrary, in this study, we propose FLight, a low-cost reading and writing system for economically less-privileged people. FLight uses ink-based Braille characters as the medium of textual representation. This helps in keeping a compact spatial representation of texts, yet achieving a low-cost status. Additionally, FLight utilizes a low-cost wearable device to enhance ease of reading by visually-impaired people. We conduct a participatory design and iterative evaluation involving five visually-impaired children in Bangladesh for more than 18 months. Our user evaluation reveals that FLight is easy-to-use, and exhibits a potential low-cost solution for economically less-privileged visually-impaired people.

Towards defending eavesdropping on NFC

Abstract Successful defense against eavesdropping on near-field communication (NFC) vastly depends on careful analysis of eavesdropping and adopting a suitable defense mechanism based on the analysis. However, such an analysis and such an adoption of a defense mechanism are yet to be attempted in the literature, even though eavesdropping is considered as one of the foremost security breaches on NFC. As a remedy to this situation, we propose an analytical model for analyzing the notion of eavesdropping, and also propose pragmatic defense mechanisms based on the model. In our formulation of the analytical model, we attempt to consider all the parameters related to eavesdropping. Based on the formulated model, we analyze individual impacts of the parameters. Our analysis reveals a key finding: the maximum possible distance of eavesdropping on near-field communication is significantly controlled by both conductivity and permeability of the material over which the wave propagates. Exploiting this finding, we propose to judiciously utilize coating with materials having high conductivity and high permeability to defend against eavesdropping. To further enhance the defense level against eavesdropping, we propose another defense mechanism using active jamming. We perform a set of real experiments to confirm effectiveness of both the mechanisms.

Poster: RailCop: Detecting Missing Rail on Railway Using Wireless Sensor Networks

In recent times, derailments due to uprooting rails on a railway track has become a banal and noteworthy occurrence in Bangladesh due to different reasons such as political unrest, mass protest, etc. However, the railway tracks in Bangladesh are yet to deploy an automated system that can prevent the losses due to derailments through early detection of missing rails on a railway track. As a remedy to this situation, in this project, we propose to develop a WSN based automated system, which can sense the discontinuity of rail blocks and thus prevent from derailment of trains.

AWZone: Ad hoc WiFi Zonification in Post-Disaster Settings

Indoor localization or zonification in disaster affected settings is a challenging research problem. Existing studies encompass localization and tracking of first-responders or fire fighters using wireless sensor networks. In addition to that, fast evacuation, routing, and planning have also been proposed. However, the problem of locating survivors or victims is yet to be explored to the full potential. State-of-the-art literature often employ infrastructure dependent solutions, for example, WiFi localization using WiFi access points exploiting fingerprinting techniques, Pedestrian Dead Reckoning (PDR) starting from known locations, etc. Owing to unpredictable and dynamic nature of disaster affected environments, infrastructure dependent solutions are seldom useful. Therefore, in this study, we propose an ad hoc WiFi zonification technique (named as AWZone) that is independent of any infrastructural settings. AWZone attempts to perform localization through exploiting commodity smartphones as a beaconing device and successively searching and narrowing down the search space. We perform two testbed experiments. The results reveal that, for a single survivor or victim, AWZone can identify the search space and estimate a location with an approximate 1.5m localization error through eliminating incorrect zones from a set of possible results.

What We Breathe As We Commute: From the Perspective of a Developing Country

Air pollution is a serious threat to public health. The city residents often spend significant time in public transports owing to long traffic tailbacks. So, the air quality inside public transports is an important factor that needs to be considered for the welfare of city residents. In this paper, we study the air quality inside public transports in a metropolitan city from the perspective of a developing country. To capture the diversity of city life, we consider the variation in traffic pattern and public transports, and analyze the data in temporal and spatial domain. Our custom-built sensing module collects data at regular intervals and detects the presence of pollutants above recommendation level. Our temporal analysis shows that concentration of air pollutants inside different public transports do not remain consistent in peak and off-peak hours. Our analysis also reveals that public transports with lower fares are more exposed to air pollutants than those with higher fares.