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We study a binary mixture of disk-shaped {\it active run and tumble } particles (${ARNPs}$) and passive particles on a two-dimensional substrate. Both types of particles are athermal. The particles interact through the soft repulsive potential. The activity of $ARNPs$ is controlled by tuning their tumbling rate. The system is studied for various sizes of passive particles keeping size of $ARNPs$ fixed. Hence the variables are, size ratio (S) of passive particles and $ARNPs$, and activity of $ARNPs$ is $v$. The characterstics dynamics of both $ARNPs$ and passive particles show a crossover from early time ballistic to later time diffusive. Furthermore, we observed that passive particles dynamics changes from diffusive to subdiffusive with respect to their size. Moreover, late time effective diffusivity $D_{eff}$ of passive particles decreases with increasing their size as in the corresponding equilibrium Stokes systems. We calculated the effective temperatures, using $D_{eff}$, $T_{a,eff}(\Delta)$ and also using speed distribution $T_{a,eff}(v)$ and compared them. The both $T_{a,eff}(\Delta)$ and $T_{a,eff}(v)$ increases linearly with activity and are in agreement with each other. Hence we can say that an effective equilibrium can be establish in such binary mixture. Our study can be useful to study the various biological systems like; dynamics of passive organels in cytoplasm, colloids etc.

In industrial environments workers can be prone to dangerous situations that may cause harm. In order to prevent accidents and fulfill legislative requirements for safe working condition, a safety system can be needed to be installed in place. In an attempt to bring a principal improvement in the safety standards offered by conventional systems in existence, a radar sensor is proposed for the detection of dangerous situations. This thesis explores the limiting performance of the radar sensor in an industrial safety system. The radar sensor is an FMCW mode MIMO radar and we develop a model to simulate the radar sensor based on its hardware design. The model is utilized to deduce and analyze the performance limits of the radar sensor, by using a Finite Element Method to determine the electromagnetic scattering response of a target in the operating frequency band, 60-64 GHz. Appropriate dielectric and magnetic properties of human tissue is assigned to obtain accurate scattering responses of a human body target. The performance analysis is done by comparing the reflection from various protruding body parts, with the reflection from the torso, over a wide range of postures of the body. Further, CFAR, a common form of detection algorithm is applied on a few of the postures to detect a protruding part the body. Finally, a discussion on the limited performance is made, and potential methods to enhance the performance of the radar sensor in an industrial safety system are suggested. I industriella miljöer kan arbetare utsättas för farliga situationer vilka kan orsaka skador. För att förhindra olyckor och uppfylla lagstadgade krav för säkra arbetsförhållanden kan säkerhetssystem behöva installeras på plats. I ett försök att åstadkomma en förbättring av de säkerhetsstandarder som erbjuds av konventionella system föreslås en radarsensor för att detektera farliga situationer. Denna avhandling undersöker möjliga begränsningar i prestanda hos en radarsensor, vilken ingår som komponent i ett industriellt säkerhetssystem. Radarsensorn är en MIMO-radar, som arbetar i FMCW-mod, och vi utvecklar en modell för att simulera radarsensorn utgående ifrån dess hårdvarudesign. Modellen används för att härleda och analysera begränsningar i prestanda hos radarsensorn, genom att med hjälp av finita elementmetoden beräkna spridningen av elektromagnetiska vågor från ett radarmål i frekvensbandet 60-64 GHz. Tillämpliga dielektriska och magnetiska egenskaper hos mänsklig vävnad har använts för att erhålla tillförlitliga data på spridningsresponsen för människokroppen. Prestandaanalysen görs genom att jämföra reflektionen från olika utskjutande kroppsdelar med reflektionen från bålen över ett stort antal kroppshållningar. Vidare, CFAR, en vanlig form av detektionsalgoritm tillämpas på några av hållningarna för att detektera utskjutande delar av kroppen. Avslutningsvis diskuteras begränsningarna i prestandan och potentiella metoder för att förbättra radarsensorns prestanda i ett industriellt säkerhetssystem föreslås.

L’histoire de vie des personnes est un enchaînement continu d’événements de nature diverse concernant, entre autres, leur famille, leur résidence et leur profession. Pour appréhender les rythmes d’évolution multiples et imbriqués de ces différents phénomènes, il est nécessaire de disposer de données spécifiques que les enquêtes biographiques permettent de saisir au mieux dans leurs interactions. Cet ouvrage confronte, en termes directement comparables, quatorze expériences de collectes biographiques menées entre 1974 et 1997 dans divers pays du Nord (France, Pologne, Italie, Roumanie), mais aussi du Sud (en Afrique : Sénégal, Mali, Cameroun; en Amérique latine : Colombie, Mexique ; en Asie : Inde) avec des objectifs et des moyens divers. Ainsi, le cheminement théorique et les options méthodologiques qui ont présidé à chacune de ces expériences sont présentés en détail et selon un plan commun dans chaque chapitre. Ces présentations sont précédées d’une analyse comparative systématique. Ce bilan est le fruit des présentations et des discussions qui ont eu lieu lors d’un séminaire international en juin 1997, organisé par l’Ined, l’Orstom (IRD) et le Réseau Socioéconomie de l’Habitat sur « l’apport des collectes biographiques pour la connaissance de la mobilité ». Les études présentées ici apportent d’utiles éléments de réflexion aux chercheurs, enseignants et étudiants, intéressés par la collecte de données susceptibles d’améliorer la connaissance des comportements individuels, en particulier dans le domaine de la mobilité. Afin de poursuivre les travaux dans cette direction, les organisateurs ont, à l’époque, constitué le Groupe de réflexion sur l’approche biographique (Grab), animé par Éva Lelièvre, dont les activités ultérieures ont donné lieu à des rencontres régulières et à de nouvelles publications (voir http://grab.site.ined.fr).

1. Préliminaires 1.1. Nom précis de l’enquête Langue d’origine : « Patterns of Spatial Mobility in the Metropolitan Area of Delhi ». Français : « Mobilités spatiales dans l’aire métropolitaine de Delhi ». 1.2. Problématique et objectifs Problématique L’évolution de l’urbanisation à l’échelle planétaire se traduit par l’émergence de grandes métropoles multimillionnaires, dans lesquelles se développent de nouvelles dynamiques urbaines. Il ne s’agit pas d’un simple changement d’échelle, mais bie...

In an Industrial Control System (ICS), its complex network of sensors, actuators and controllers have raised security concerns for critical infrastructures and industrial production units. This opinion paper strives to initiate discussion on the design algorithms which can segregate attacks from faults. Most of the proposed anomaly detection mechanisms are not able to differentiate between an attack and an anomaly due to a fault. We argue on the need of solving this important problem form our experiences in CPS security research. First, we motivate using analysis of studies and interviews though economical and psychological aspects. Then main challenges are highlighted. Further, we propose multiple directions of approach with suitable reasoning and examples from ICS systems.

The number of active users of Wi-Fi Direct Device-to-Device file sharing applications on Android has exceeded 1.8 billion. Wi-Fi Direct, also known as Wi-Fi P2P, is commonly used for peer-to-peer, high-speed file transfer between mobile devices, as well as a close proximity connection mode for wireless cameras, network printers, TVs and other IoT and mobile devices. For its end users, such type of direct file transfer does not incur cellular data charges. However, despite the popularity of such applications, we observe that the software vendors tend to prioritize the ease of user flow over the security in their implementations, which leads to serious security flaws. We perform a comprehensive security analysis in the context of security and usability and report our findings in the form of 17 Common Vulnerabilities and Exposures (CVE) which have been disclosed to the corresponding vendors. To address the similar flaws at the early stage of the application design, we propose a joint consideration of security and usability for such applications and their protocols that can be visualized in form of a customised User Journey Map (UJM).

Direct-sequence spread spectrum (DSSS) has been recognized as an effective jamming resilient technique. However, the effectiveness of DSSS relies on the use of either pre-shared unique secret keys or a bank of public codes, which can be prohibitively expensive in future large-scale decentralized wireless networks, e.g., the Internet of Things. To tackle this problem, in this work we develop a new framework for self-controlled physical-layer-security-based spreading sequence generation. Specifically, we exploit the shared randomness inherent in wireless channels to generate and refresh secret seeds at each communicating node using shared randomness extraction, entropy pooling and random seed generation. The generated secret seeds are then utilized to perform DSSS. To evaluate the performance, we implement our framework on software defined radio platform and examine the successful transmission probability of the system under various models of broadband jamming along with an special case wherein adversary is assumed to have leaked information on key rate. Both our analysis and real-world measurements confirm that communication systems based on our framework can achieve jamming-resilient communications without requiring pre-shared sequences.

Pycnodysostosis (the Toulouse-Lautrec syndrome) is a rare autosomal-recessive disorder of osteoclast dysfunction. This disorder was first described by Maroteaux and Lamy in 1962. We describe anaesthetic management of a 35-year-old female having pyknodysostosis with fracture shaft left femur with anticipated difficult intubation. Therefore, spinal anesthesia was planned for her fracture fixation. The intra- and postoperative period remains uneventful.