Joint Optimization for Social Content Delivery in Wireless Networks

Over the last decade, success of social networks has significantly reshaped how people consume information. Recommendation of contents based on user profiles is well-received. However, as users become dominantly mobile, little is done to consider the impacts of the wireless environment, especially the capacity constraints and changing channel. In this dissertation, we investigate a centralized wireless content delivery system, aiming to optimize overall user experience given the capacity constraints of the wireless networks, by deciding what contents to deliver, when and how. We propose a scheduling framework that incorporates content-based reward and deliverability. Our approach utilizes the broadcast nature of wireless communication and social nature of content, by multicasting and precaching. Results indicate this novel joint optimization approach outperforms existing layered systems that separate recommendation and delivery, especially when the wireless network is operating at maximum capacity. Utilizing limited number of transmission modes, we significantly reduce the complexity of the optimization. We also introduce the design of a hybrid system to handle transmissions for both system recommended contents ('push') and active user requests ('pull'). Further, we extend the joint optimization framework to the wireless infrastructure with multiple base stations. The problem becomes much harder in that there are many more system configurations, including but not limited to power allocation and how resources are shared among the base stations ('out-of-band' in which base stations transmit with dedicated spectrum resources, thus no interference; and 'in-band' in which they share the spectrum and need to mitigate interference). We propose a scalable two-phase scheduling framework: 1) each base station obtains delivery decisions and resource allocation individually; 2) the system consolidates the decisions and allocations, reducing redundant transmissions. Additionally, if the social network applications could provide the predictions of how the social contents disseminate, the wireless networks could schedule the transmissions accordingly and significantly improve the dissemination performance by reducing the delivery delay. We propose a novel method utilizing: 1) hybrid systems to handle active disseminating requests; and 2) predictions of dissemination dynamics from the social network applications. This method could mitigate the performance degradation for content dissemination due to wireless delivery delay. Results indicate that our proposed system design is both efficient and easy to implement.

Reimagining the Public Library as Public Space

Once regarded as the public’s center of knowledge and information, public libraries today are challenged by the rise of mobile technology and the Internet. Information behavior of everyday library patrons have transformed to rely on instant access of information through Google search instead of the resources housed in their local libraries. The focus of public library design is shifting from storing & protecting valuable resources (books) to the experience of an active public space of learning, engaging and reading. This thesis reimagines a public library branch in East Baltimore City by evaluating the architecture of public library examples of the past and of today. By understanding the user experience of the three key elements of public library design – procession, services & flexible space - a new public library design that engages and responds to the local community can be proposed.

Value creation through trust in technological-mediated social participation

In this article, we advocate for the use of a social-technical model of trust to support interaction designers in further reflecting on trust-enabling interaction design values that foster participation. Our rationale is built upon the believe that technological-mediated social participation needs trust, and it is with trust-enabling interactions that we foster the will for collaborate and share—the two key elements of participation. This article starts by briefly presenting a social-technical model of trust and then moves on with establishing authors rational that interconnects trust with technological-mediated social participation. It continues by linking the trust value to the context of design critique and critical design, and ends by illustrating how to incorporate the trust value into design. This is achieved by proposing an analytical tool that can serve to inform interaction designers to better understand the potential design options and reasons for choosing them.

Diseño positivo: Innovación centrada en el bienestar humano

El ‘Diseño Positivo’ es una filosofía de innovación desarrollada por investigadores líderes en diseño experiencial de la facultad de Diseño Industrial de la Universidad Tecnológica de Delft (TU Delft), en Los Países Bajos. El ‘Diseño Positivo’ plantea estrategias de innovación que buscan esencialmente promover, facilitar o fomentar el bienestar de los usuarios. Lo hace por medio de la aplicación práctica del conocimiento derivado de la investigación científica sobre la experiencia humana: psicología positiva, psicología emocional, economía conductual. Entre los descubrimientos que se han dilucidado se encuentran modelos detallados sobre el comportamiento humano, sobre la forma en que tomamos decisiones, sobre cómo las emociones se suscitan, e incluso sobre cómo está moldeado nuestro sentido del gusto partiendo de teorías evolutivas. El Diseño Positivo busca combinar estos conocimientos científicos con marcos conceptuales sobre la experiencia del usuario (User Experience – UX) en procesos de innovación En la presentación, Simón discutió las premisas básicas del Diseño Positivo, y en especial, cómo estas pueden ser aplicadas a procesos de innovación para crear productos y servicios que generen un impacto positivo en el bienestar psicológico y felicidad de las personas. Además, discutió cómo este conocimiento podría ser aplicado en procesos de innovación en las bibliotecas

Colaboración fabricante-distribuidor en la cadena de suministro para la tecnología aplicada al punto de venta y la mejora de la experiencia de compra

A lo largo de este trabajo se lleva a cabo una investigación sobre la evolución de las relaciones comerciales entre fabricantes y distribuidores, con especial atención en la colaboración conjunta a la hora de comercializar los productos en el punto de venta. El empleo de nuevas herramientas tecnológicas en el establecimiento facilita el merchandising de presentación, ofreciendo ventajas competitivas para los agentes de la cadena de suministros y nuevas experiencias de compra para los consumidores. Una vez analizada la parte teórico-conceptual del trabajo se lleva a cabo el análisis de un caso práctico sobre los beneficios de la tecnología Radio Frequency Identification (RFID) implantada en la empresa Decathlon. Estos sistemas se han convertido en un aliado clave para la mejora de los procesos de negocio, mejorando la gestión de la compañía y la fidelización de los clientes.

Collaborative filtering and deep learning based recommendation system for cold start items

Recommender system is a specific type of intelligent systems, which exploits historical user ratings on items and/or auxiliary information to make recommendations on items to the users. It plays a critical role in a wide range of online shopping, e-commercial services and social networking applications. Collaborative filtering (CF) is the most popular approaches used for recommender systems, but it suffers from complete cold start (CCS) problem where no rating record are available and incomplete cold start (ICS) problem where only a small number of rating records are available for some new items or users in the system. In this paper, we propose two recommendation models to solve the CCS and ICS problems for new items, which are based on a framework of tightly coupled CF approach and deep learning neural network. A specific deep neural network SADE is used to extract the content features of the items. The state of the art CF model, timeSVD++, which models and utilizes temporal dynamics of user preferences and item features, is modified to take the content features into prediction of ratings for cold start items. Extensive experiments on a large Netflix rating dataset of movies are performed, which show that our proposed recommendation models largely outperform the baseline models for rating prediction of cold start items. The two proposed recommendation models are also evaluated and compared on ICS items, and a flexible scheme of model retraining and switching is proposed to deal with the transition of items from cold start to non-cold start status. The experiment results on Netflix movie recommendation show the tight coupling of CF approach and deep learning neural network is feasible and very effective for cold start item recommendation. The design is general and can be applied to many other recommender systems for online shopping and social networking applications. The solution of cold start item problem can largely improve user experience and trust of recommender systems, and effectively promote cold start items.

Human-Computer interaction methodologies applied in the evaluation of haptic digital musical instruments

Recent developments in interactive technologies have seen major changes in the manner in which artists, performers, and creative individuals interact with digital music technology; this is due to the increasing variety of interactive technologies that are readily available today. Digital Musical Instruments (DMIs) present musicians with performance challenges that are unique to this form of computer music. One of the most significant deviations from conventional acoustic musical instruments is the level of physical feedback conveyed by the instrument to the user. Currently, new interfaces for musical expression are not designed to be as physically communicative as acoustic instruments. Specifically, DMIs are often void of haptic feedback and therefore lack the ability to impart important performance information to the user. Moreover, there currently is no standardised way to measure the effect of this lack of physical feedback. Best practice would expect that there should be a set of methods to effectively, repeatedly, and quantifiably evaluate the functionality, usability, and user experience of DMIs. Earlier theoretical and technological applications of haptics have tried to address device performance issues associated with the lack of feedback in DMI designs and it has been argued that the level of haptic feedback presented to a user can significantly affect the user’s overall emotive feeling towards a musical device. The outcome of the investigations contained within this thesis are intended to inform new haptic interface.

Child-centred design supported by comprehensive child application use analysis

Since children already use and explore applications on smartphones, we use this as the starting point for design. Our monitoring and analysis framework, BaranC, enables us to discover and analyse which applications children uses and precisely how they interact with them. The monitoring happens unobtrusively in the background so children interact normally in their own natural environment without artificial constraints. Thus, we can discover to what extent a child of a particular age engages with, and how they physically interact with, existing applications. This information in turn provides the basis for design of new child-centred applications which can then be subject to the same comprehensive child use analysis using our framework. The work focuses on the first aspect, namely, the monitoring and analysis of current child use of smartphones. Experiments show the value of this approach and interesting results have been obtained from this precise monitoring of child smartphone usage.

Studio del processo di progettazione di una stampella sensorizzata

Lo studio presentato in questa tesi vuole riportare la ricerca e l’analisi di una nuova esperienza di utilizzo di una stampella, spinto dalla richiesta di migliorare la performance e l’interfaccia dello strumento con un paziente con rilevanti difficoltà motorie. Analizzando lo stato dell’arte e la ricerca in ambito ortopedico, la stampella risulta essere lo strumento più comunemente utilizzato in caso di riabilitazione o difficoltà motorie, ma, allo stesso tempo, comporta rischi e ulteriori danni al paziente, nel caso vi sia un uso scorretto dello strumento. Lo scopo principale del progetto è fornire un supporto, sia al paziente, sia alla terapia, tramite l’ottimizzazione e il miglioramento di alcuni elementi costituenti di una stampella e l’implementazione di un nuovo servizio. Durante lo studio sono stati sfruttati i metodi dell’ingegneria industriale, utili per le fasi di sviluppo del progetto, ma si è cercato anche di dare importanza alla user experience, riportando considerazioni e opinioni di diversi utilizzatori della stampella. Si spera che il risultato sia uno strumento funzionale, utile e soprattutto che vada incontro alle esigenze non solo dell’utente, ma anche delle figure che lo assistono, come il medico ortopedico o il fisioterapista.

Sensing presence (PreSense) ontology : user modelling in the semantic sensor web

Increasingly, people's digital identities are attached to, and expressed through, their mobile devices. At the same time digital sensors pervade smart environments in which people are immersed. This paper explores different perspectives in which users' modelling features can be expressed through the information obtained by their attached personal sensors. We introduce the PreSense Ontology, which is designed to assign meaning to sensors' observations in terms of user modelling features. We believe that the Sensing Presence ( PreSense ) Ontology is a first step toward the integration of user modelling and "smart environments". In order to motivate our work we present a scenario and demonstrate how the ontology could be applied in order to enable context-sensitive services. © 2012 Springer-Verlag.

Sensing presence (PreSense) ontology:user modelling in the semantic sensor web

Increasingly, people's digital identities are attached to, and expressed through, their mobile devices. At the same time digital sensors pervade smart environments in which people are immersed. This paper explores different perspectives in which users' modelling features can be expressed through the information obtained by their attached personal sensors. We introduce the PreSense Ontology, which is designed to assign meaning to sensors' observations in terms of user modelling features. We believe that the Sensing Presence ( PreSense ) Ontology is a first step toward the integration of user modelling and "smart environments". In order to motivate our work we present a scenario and demonstrate how the ontology could be applied in order to enable context-sensitive services. © 2012 Springer-Verlag.

Personalized touristic routes implementing semantic web on GIS

Nowadays, when a user is planning a touristic route is very difficult to find out which are the best places to visit. The user has to choose considering his/her preferences due to the great quantity of information it is possible to find in the web and taking into account it is necessary to do a selection, within small time because there is a limited time to do a trip. In Itiner@ project, we aim to implement Semantic Web technology combined with Geographic Information Systems in order to offer personalized touristic routes around a region based on user preferences and time situation. Using ontologies it is possible to link, structure, share data and obtain the result more suitable for user's preferences and actual situation with less time and more precisely than without ontologies. To achieve these objectives we propose a web page combining a GIS server and a touristic ontology. As a step further, we also study how to extend this technology on mobile devices due to the raising interest and technological progress of these devices and location-based services, which allows the user to have all the route information on the hand when he/she does a touristic trip. We design a little application in order to apply the combination of GIS and Semantic Web in a mobile device.

Semantic web adoption: online tools for web evaluation and metadata extraction

This work briefly analyses the difficulties to adopt the Semantic Web, and in particular proposes systems to know the present level of migration to the different technologies that make up the Semantic Web. It focuses on the presentation and description of two tools, DigiDocSpider and DigiDocMetaEdit, designed with the aim of verifYing, evaluating, and promoting its implementation.

Personalized touristic routes implementing semantic web on GIS

Nowadays, when a user is planning a touristic route is very difficult to find out which are the best places to visit. The user has to choose considering his/her preferences due to the great quantity of information it is possible to find in the web and taking into account it is necessary to do a selection, within small time because there is a limited time to do a trip. In Itiner@ project, we aim to implement Semantic Web technology combined with Geographic Information Systems in order to offer personalized touristic routes around a region based on user preferences and time situation. Using ontologies it is possible to link, structure, share data and obtain the result more suitable for user's preferences and actual situation with less time and more precisely than without ontologies. To achieve these objectives we propose a web page combining a GIS server and a touristic ontology. As a step further, we also study how to extend this technology on mobile devices due to the raising interest and technological progress of these devices and location-based services, which allows the user to have all the route information on the hand when he/she does a touristic trip. We design a little application in order to apply the combination of GIS and Semantic Web in a mobile device.