Secret key distribution leveraging color shift over visible light channel

Given the widely adoption of screen and camera in many electronic devices, the visible light communication (VLC) over screen-to-camera channel emerges as a novel short range communication technique in recent years. Active research explores various ways to convey messages over screen-camera channel, such as barcode and unobtrusive optical pattern. However, with the prevalence of LED screens of wide viewing angles and mobile devices equipped with high standard cameras, the threat of information leakage over screen-to-camera channel becomes in-negligible. Few studies have discussed how to ensure the security of data transmission over screen-to-camera channel. In this paper, we propose a secret key distribution system leveraging the unique color shift property over visible light channel. To facilitate such design, we develop a practical secret key matching based method to map the secret key into gridded optical patterns on screen, which can only be correctly recognized by the legitimate user through an accessible region and allow regular data stream transmission through valid grids. The proposed system is prototyped with off-the-shelf devices and validated under various experimental scenarios. The results show that our system can achieve high bit-decoding accuracy for the legitimate users while maintaining comparable data throughput as regular unobtrusive VLC systems with very low recovery accuracy of the encrypted data for the attackers

Multi-user interface for co-located real-time work with digital mock-up: a way to foster collaboration?

Nowadays more and more industrial design activities adopt the strategy of Concurrent Engineering (CE), which changes the way to carry out all the activities along the product’s lifecycle from sequential to parallel. Various experts of different activities produce technical data using domain-specific software. To augment the interoperability among the technical data, a Digital Mock-Up (DMU), or a Building Information Model (BIM) in architectural engineering can be used. Through an appropriate Computer–Human Interface (CHI), each expert has his/her own point-of-view (POV) of a specific representation of DMU’s technical data according to an involved domain. When multiple experts work collaboratively in the same place and at the same time, the number of CHIs is also multiplied by the number of experts. Instead of multiple CHIs, therefore, a unique CHI should be developed to support the multiview and multi-interaction collaborative works. Our contributions in this paper are (a) a concept of a CHI system with multi-view and multi-interaction of DMU for multiple users in collaborative design; (b) a state of the art of multi-view and multi-interaction metaphors; (c) an experiment to evaluate a collaborative application using multi-view CHI. The experimental results indicate that, in multi-view CHI working condition, users are more efficient than in the other two working conditions (multiple CHIs and split view CHI). Moreover, in multi-view CHI working condition, the user, who is helping the other, takes less mutual awareness of where the other collaborator works than the other two working conditions.Bourse de thèse de CSC (China Scholarship Council

Perceptual Affordances of Wall-Sized Displays for Visualization Applications: Color

International audienceWall-sized displays offer the opportunity to display very large information spaces. Most data representations can be scaled to wall size but display walls are not simply big desktop monitors. We do not yet know how the perceptual affordances of a wall, such as the wide viewing angles they cover, affect how data is perceived and comprehended. In this paper we call for more studies on the perception of data on wall-sized displays and discuss-with the example of color-several aspects of wall setups that we hypothesize will most affect the perception of this visual variable

Etäisyyden huomioiva kaksiulotteinen viivakoodi mobiilikäyttötapauksiin

Global internet use is becoming increasingly mobile, and mobile data usage is growing exponentially. This puts increasing stress on the radio frequency spectrum that cellular and Wi-Fi networks use. As a consequence, research has also been conducted to develop wireless technologies for other parts of the electromagnetic spectrum – namely, visible light. One approach of using the visible light channel for wireless communication leverages barcodes. In this thesis, we propose a 2D barcode that can display different information based on the distance between the barcode and the scanner. Earlier research on distance-sensitive barcodes has focused on providing a closer viewer more information as a closer viewer can see more detail. In contrast, we target use cases where a clear physical separation between users of different roles can be made, such as presentation systems. We evaluate two methods of achieving distance-awareness: color-shifting of individual colors, where a color changes tone at longer distances, and color blending, where two colors blend into a third color at longer viewing distances. Our results show that a modern smartphone is capable of leveraging color-shifting in ideal conditions, but external changes such as ambient lighting render color-shifting unusable in practical scenarios. On the other hand, color blending is robust in varying indoor conditions and can be used to construct a reliable distance-aware barcode. Accordingly, we employ color blending to design a distance-aware barcode. We implement our solution in an off-the-shelf Android smartphone. Experimental results show that our scheme achieves a clear separation between close and far viewers. As a representative use case, we also implement a presentation system where a single barcode provides the presenter access to presentation tools and the audience access to auxiliary presentation material.Maailmanlaajuinen internetin käyttö muuttuu yhä liikkuvammaksi, ja mobiilidatan käyttö kasvaa eksponentiaalisesti. Tämä kohdistaa yhä suurempia vaatimuksia radiotaajuusspektriin, jota mobiili- ja Wi-Fi-verkot käyttävät. Näin ollen tutkijat ovat kehittäneet langattomia teknologioita hyödyntäen myös muita sähkömagneettisen spektrin osia – erityisesti näkyvää valoa. Yksi näkyvän valon sovellus langattomassa viestinnässä ovat viivakoodit. Tässä työssä kehitämme kaksiulotteisen viivakoodin, joka pystyy välittämään eri tietoa katselijoille eri etäisyyksillä. Aiempi etäisyyden huomioivien viivakoodien tutkimus on keskittynyt tarjoamaan lähellä olevalle katselijalle enemmän tietoa, koska läheinen katselija näkee viivakoodin tarkemmin. Sitä vastoin me keskitymme käyttötapauksiin, joissa eri käyttäjäroolien välillä on selkeä etäisyydellinen ero, kuten esimerkiksi esitelmissä puhujan ja yleisön välillä. Tarkastelemme kahta menetelmää: yksittäisten värien muutoksia etäisyyden muuttuessa ja kahden värin sekoittumista etäisyyden kasvaessa. Tulostemme perusteella nykyaikainen älypuhelin pystyy hyödyntämään yksittäisten värien muutoksia ihanteellisissa olosuhteissa, mutta ulkoiset tekijät, kuten ympäristön valaistus, aiheuttavat liian suuria värimuutoksia käytännön käyttötapauksissa. Toisaalta värien sekoittuminen on johdonmukaista muuttuvassa sisäympäristössä ja sitä voidaan käyttää luotettavan viivakoodin luomisessa. Näin ollen me suunnittelemme etäisyyden huomioivan viivakoodin hyödyntäen värien sekoittumista. Toteutamme ratkaisumme yleisesti saatavilla olevalle Android-älypuhelimelle. Kokeellisten tulostemme perusteella menetelmämme saavuttaa selkeän erottelun läheisten ja kaukaisten katselijoiden välillä. Esimerkkikäyttötapauksena toteutamme myös esitelmäjärjestelmän, jossa sama viivakoodi antaa lähellä olevalle puhujalle nopean pääsyn esitystyökaluihin ja kauempana olevalle yleisölle pääsyn esityksen apumateriaaliin

A Multi-view and Multi-interaction System for Digital-mock up’s collaborative environment

The current industrial PLM tool generally relies on Concurrent Engineering (CE), which involves conducting product design and manufacturing stages in parallel and integrating technical data for sharing among different experts in parallel. Various experts use domain-specific software to produce various data. This package of data is usually called Digital mock-up (DMU), as well as Building Information Model (BIM) in architectural engineering. For sharing the DMU data, many works have been done to improve the interoperability among the engineering software and among the models in domains of mechanical design and eco-design. However, the computer-human interaction (CHI) currently used in the context of CE project reviews is not optimized to enhance the interoperability among various experts of different domains. Here the CHI concerns both complex DMU visualization and multi-users interaction. Since the DMU has its multiple representations according to involved domains, therefore when various experts need to work together on the DMU they may prefer their own point-of-view on the DMU and proper manner to interact with the DMU.With the development of 3D visualization and virtual reality CHI technology, it is possible to devise more intuitive tools and methods to enhance the interoperability of collaboration among experts both in multi-view and multi-interaction for co-located synchronous collaborative design activities. In this paper, we discuss the different approaches of displaying multiple point-of-views of DMU and multiple interactions with DMU in the context of 3D visualization, virtual reality and augmented reality. A co-located collaborative environment of CHI supporting system is proposed. This collaborative environment allows the experts to see respectively the multiple point-of-view of the DMU in front of a unique display system and to interact with the DMU in using different metaphors according to their specific needs. This could be used to assist collaborative design during project review where some decision on product design solution should be made.CSC (China Scholarship Council

AN EFFICIENT AND PRIVACY PRESERVING OF DETECTING ONLINE GUESSING ATTACKS USING CAPTCHA

In our work we set up an innovative security primitive depending on unsolved tough problems. It is graphical password system family that include Captcha expertise as well as graphical passwords. Several number of graphical password schemes were proposed in literature in the traditional works. Captcha is a standard security method that has achieved a limited success when compared to cryptographic primitives on basis of tough math problems.   The systems deals quite a lot of online dictionary attacks on passwords that were most important security threat for a variety of online services such as protection against relay attacks, tough to shoulder-surfing attacks when combined with dual-view knowledge. Several schemes are converted to CaRP schemes which are clicked-based graphical passwords. The system is click-based graphical passwords, in which series of clicks on an image derives a password and require solving a challenge in each login and impact on usability is mitigated by means of adapting image complexity level based on login history of account as well as machine used to log in

Modelling and evaluating drivers’ interactions with in-vehicle information systems (IVIS)

Evaluating the usability of In-Vehicle Information Systems (IVIS) guides engineers in understanding the interaction design limitations of current systems and assessing the potential of concept technologies. The complexity and diversity of the driving task presents a unique challenge in defining usability: user-IVIS interactions create a dual-task scenario, in which conflicts can arise between the primary driving tasks and secondary IVIS tasks. This, and the safety-critical nature of driving, must be specified in defining and evaluating IVIS usability.Work was carried out in the initial phases of this project to define usability for IVIS and to develop a framework for evaluation. One of the key findings of this work was the importance of context-of-use in defining usability, so that specific usability criteria and appropriate evaluation methods can be identified. The evaluation methods in the framework were categorised as either analytic, i.e. applicable at the earliest stages of product development to predict performance and usability; or empirical, i.e. to measure user performance under simulated or real-world conditions. Two case studies have shown that the evaluation framework is sensitive to differences between IVIS and can identify important usability issues, which can be used to inform design improvements.The later stages of the project have focussed on Multimodal Critical Path Analysis (CPA). Initially, CPA was used to predict IVIS task interaction times for a stationary vehicle. The CPA model was extended to produce fastperson and slowperson task time estimates, as well as average predictions. In order for the CPA to be of real use to designers of IVIS, it also needed to predict dual-task IVIS interaction times, i.e. time taken to perform IVIS tasks whilst driving. A hypothesis of shared glances was developed, proposing that drivers are able to monitor two visual information sources simultaneously. The CPA technique was extended for prediction of dual-task interaction times by modelling this shared glance pattern. The hypothesis has important implications for theories of visual behaviour and for the design of future IVIS

The Use of Multiple Slate Devices to Support Active Reading Activities

Reading activities in the classroom and workplace occur predominantly on paper. Since existing electronic devices do not support these reading activities as well as paper, users have difficulty taking full advantage of the affordances of electronic documents. This dissertation makes three main contributions toward supporting active reading electronically. The first contribution is a comprehensive set of active reading requirements, drawn from three decades of research into reading processes. These requirements explain why existing devices are inadequate for supporting active reading activities. The second contribution is a multi-slate reading system that more completely supports the active reading requirements above. Researchers believe the suitability of paper for active reading is largely due to the fact it distributes content across different sheets of paper, which are capable of displaying information as well as capturing input. The multi-slate approach draws inspiration from the independent reading and writing surfaces that paper provides, to blend the beneficial features of e-book readers, tablets, PCs, and tabletop computers. The development of the multi-slate system began with the Dual-Display E-book, which used two screens to provide richer navigation capabilities than a single-screen device. Following the success of the Dual-Display E-book, the United Slates, a general-purpose reading system consisting of an extensible number of slates, was created. The United Slates consisted of custom slate hardware, specialized interactions that enabled the slates to be used cooperatively, and a cloud-based infrastructure that robustly integrated the slates with users' existing computing devices and workflow. The third contribution is a series of evaluations that characterized reading with multiple slates. A laboratory study with 12 participants compared the relative merits of paper and electronic reading surfaces. One month long in-situ deployments of the United Slates with graduate students in the humanities found the multi-slate configuration to be highly effective for reading. The United Slates system delivered desirable paper-like qualities that included enhanced reading engagement, ease of navigation, and peace-of-mind while also providing superior electronic functionality. The positive feedback suggests that the multi-slate configuration is a desirable method for supporting active reading activities