L'émergence et la propagation des technologies de communication à travers le monde ont facilité l'accélération du rythme de l'innovation dans une multitude de domaines. Avec un accès quasi-continu aux flux de l'information, la façon dont les humains vivent a changé, et avec elle ont évolué la structure et la fonction des entreprises, des marchés et de leurs composants. Dans cette thèse, nous explorons la co-évolution des entreprises et des marchés et analysons la création d'une nouvelle architecture organisationnelle qui résulte de cette co-évolution.Dans le chapitre 1, nous explorions les nombreuses branches de la littérature sur la théorie de la firme et la confrontons au phénomène de platformization des marchés au travers de l'étude d'eBay. Suite à l'analyse détaillée de cette étude de cas, le chapitre 1 conclut que le concept de l'entreprise a subi une métamorphose et que ses contours se redéfinissent aujourd'hui au-delà des définitions traditionnelles et contemporaines de l'entreprise. Pour résoudre ce problème, nus proposons la notion d'équivalence firme / marché. Ce concept sera ensuite utilisé dans les trois autres chapitres de la thèse.Quand les économistes voient une défaillance de marché, les entrepreneurs voient une opportunité d'affaire. Les entreprises d'aujourd'hui sont un entrelacement complexe d'interactions qui répondent aux défaillances du marché. Dans ce chapitre 2, nous expliquons comment les entreprises adressent ces opportunités de marchés grâce à des stratégies d'intermédiation passant par la création de plates-formes. Non seulement les entreprises facilitent l'activité du marché en fournissant aux autres participants des ressources de base, mais elles prennent également un rôle de premier plan dans la régulation de l'ensemble des activités économiques ainsi générées. L'objectif du chapitre 2 est d'explorer le phénomène de la double fonction de l'entreprise (création de marchés et soutien du marché) grâce à la notion d'équivalence firme / marché. Nous expliquons le rôle des entreprises qui choisissent de se positionner comme intermédiaire et qui prennent à leur charge la construction, le fonctionnement et le support de la plate-forme. Dans la littérature, ces entreprises sont appelées entreprises centrales, keystones, catalyseurs, ou tout simplement plates-formes. Ces entreprises sont capables d'attirer à elles une multitude de partenaires qui forment ce qu'une partie de la littérature appelle des écosystèmes d'affaires.Le chapitre 3 propose un regard différent sur la stratégie de création d'une plate-forme. Alors que dans le chapitre 2 nous nous sommes concentrés sur les entreprises qui créent et soutiennent les plates-formes, dans ce troisième chapitre, nous examinons de plus près les autres participants. Nous abordons ces participants comme des entreprises-satellites en raison de leur tendance à graviter vers les créateurs et les opérateurs de plate-forme. Nous étudions le rôle de ces entreprises-satellites dans les écosystèmes à base de plate-forme et observons que certaines entreprises-satellites peuvent potentiellement faire peser des menaces sur les détenteurs de plate-forme. Nous discutons ensuite les questions des clusters et du multi-homing, ainsi que la façon dont ces phénomènes affectent les entreprises centrales et leurs écosystèmes d'affaires. Nous concluons que ces comportements sont une source de pression concurrentielle entre les détenteurs de plateforme. Le chapitre 4 traite de la dynamique de l'équivalence entreprise / marché. Idéalement, l'équivalence entreprise / marché présente deux dimensions : l'innovation et le développement commercial. Dans ce modèle, la plate-forme est un artefact socio-technique central qui soutient les stratégies d'ouverture par rapport à ces deux dimensions. Elle facilite le partage et les échanges entre les participants. Ces systèmes ne sont pas statiques. / Emergence and spread of telecommunication technologies throughout the world facilitated acceleration in the pace of innovationin multitude of domains. Having access to the ongoing stream of information, the way human live has changed, and with it evolved the appearance and function of firms, markets, and their constituents. In this thesis we explore the co-evolution of firms and markets and observe the creation of new organizational architecture that resultas from this co-evolution. In chapter 1 we explore the numerous branches of the theory of the firm lterature and confront it to the phenomenon of platformization of markets through the study of the eBay case. Following the detailed annalysis of this case study, chapter 1 concludes that the concept of firm has undergone metamorphosis and has been redefined beyond the traditional and contemporary definitions of the firm. To adress this, we hence propose the concept of film / market equivalency. This concept is thoroughly explained ans discussed in the three chapters that follow. What the economists call a market failure, the entrepreneurs call a market opportunity. Firms today are the intricate interlacing of interactons, which arise in response to market failures. In chapter 2 we describe how the market opportunities that emerge as a result are adressed by the firms through market support strategy, i.e through creation of platforms. Not only do the firms facilitate marketa ctivity by providing participants with basic ressources, firm also take up a leading role in the regulation of all of their creation's activities. The purpose of chapter 2 is to explore the phenomenon of concurrent double function of firm, market creation and market support, through the concept of film / market equivalency. We explain the role of firms that that choose to position themselves as intermediaries and take charge over platform construction, operation and support. In the literature, ssuch firms are referred to as central partners who form what the management calls business ecosystems. Chapter 3 discusses a different take on the platform creation strategy. Whereas in chapter 2 we focused on the types of firms that create and support the platforms,in the third chapter we take a closer look at the constituents of platforms : the small players. In text we adress these players as "firms-satellites" due to their tendency to gravitate toward creators and operators of platforms. We study the role of these firms-staellites in the platform-based ecosystems and identify that some of firms-satellites may potentially bear threats to the platform owners. We then discuss the issues of clustering and multi-homing as welle as how these issues affect central firms, their business ecosystems and whether or not these behaviors are a source of competitive pressure. Chapter 4 discusses the dynamics of firm / market equivalency. Ideally, firm / market equivalency has two dimensions : innovation and business development. In this model, the platfform is a central sociotechnical artefact that supports openness strategies in both dimensions. It facilitates sharing and exchanges among participants. Such systems are not static. They co-evolve with their constituents : the participants and the platform owner. This chapter explores the dynamics involved in firm / market equivalency models. For each stage of development (birth, expansion, leadership, renewal), we study the architecture of the platform, the behaviour of participants and the strategic responseof the platform owner. We conclude the thesis with discussion ofa ntitrust issues that do or may arise as the result of employment of amrket creation and support strategies.

In this thesis, we consider maximized power allocation of non-orthogonal multiple ac- cess (NOMA) schemes since it outperforms than orthogonal multiple access (OMA) for the high altitude platform networks (HAPNETs) both in the back- haul and access links. Secondly, we propose a cluster formation (CF) algorithm and power-bandwidth resource allocation (PB-RA) for solving the resource management of HAPNETs. We adopt the particle swarm optimization (PSO) algorithm to explore the optimal de- ployment of high altitude platforms (HAPs) and unmanned aerial vehicles (UAVs) iteratively by a given swarm size. By PSO, we provide the best deployment under a given iteration number. Besides that, numerical results show that the NOMA schemes have better performance than OMA ones concerning different network control factors like the number of BSs, HAPs, and UAVs.

El presente trabajo de investigación se titula: “Plataformas digitales y su participación en la ocupabilidad en hoteles 3 estrellas en Miraflores - Lima, 2018”, el cual se realizó con el objetivo de determinar si las plataformas digitales participan en la ocupabilidad en hoteles de la categoría tres estrellas en Miraflores, uno de los distritos más turísticos de Lima. El mismo que tiene un enfoque cualitativo y tipo de investigación descriptiva-exploratoria porque está basado principalmente en observación directa y entrevistas semiestructuradas a administradores de hoteles tres estrellas en Miraflores, turistas, funcionarios en el sector hotelero, especialistas en plataformas digitales, e-commerce y usuarios de plataformas digitales hoteleras de quienes se ha obtenido información actual del escenario de economía global y local. Esta investigación es de suma importancia para el sector hotelero de lujo y upscale que no es ajeno al uso de estas plataformas y se benefician de estas interacciones atrayendo a clientes y potenciales clientes que basan su elección de reserva en la información, imágenes y/o videos en alta calidad de los detalles que presentan las habitaciones y áreas del hotel que visualizan en la web, evitando los intermediarios. / This research paper is entitled: "Digital platforms and their participation on occupability in 3 star hotels in Miraflores - Lima, 2018", which was carried out with the objective of determining whether digital platforms influence hotel occupability of the three star category in Miraflores, one of the most touristic districts of Lima. The same one that has a qualitative approach and type of descriptive-exploratory research because it is mainly based on direct observation and semi-structured interviews with administrators of three-star hotels in Miraflores, tourists, officials in the hotel sector, specialists in digital platforms, e-commerce and hotel digital platform users from whom current information has been obtained from the global and local economy scenario. This research is of paramount importance for the upscale and upscale hotel sector that is no stranger to the use of these platforms and benefits from these interactions by attracting customers and potential customers who base their choice of reservation on information, images and / or videos. In high quality of the details presented by the rooms and areas of the hotel that are displayed on the web, avoiding intermediaries. / Tesis

Social media platforms are interconnected environments that influence each other. Information from one social media platform spreads to another. This thesis proposes a platform-independent framework to analyze information transfer across social media platforms. This thesis uses Symbolic Transfer Entropy and Statistical Significance Test to measure influence and optimize the time window of influence between different platforms. To validate the framework, the thesis analyses the temporal activity dynamics and the information transfer across three different platforms, Reddit, Twitter and GitHub. Two data driven studies are described in this thesis. The first study finds the optimum time windows of influence between the three platforms during two different cyber attack events on cryptocurrency exchanges. It finds that specific types of activities are more influential than others, and optimum time interval changes with pre, during, and post event days. The second study applies information revealed in the first study and specifically the optimal time window to link cross-platform information cascades from Twitter and Reddit. The case-study is a heuristic that, we show, can reduce the search space for connecting information cascades across different platforms.

Major transportation and land use problems are experienced in the Menlyn precinct in Tshwane. Current infrastructure allows motor vehicles to dominate public transport and pedestrian thoroughfare. Pedestrians and motor vehicles are placed in danger and traffic problems occur when taxis and buses make use of road lanes and sidewalks to stop. The interaction and superposition of these problems are manifested as a fracture in the urban framework, disconnecting people, environments and different transport modes from one another and the rest of Tshwane. The aim of this design proposal is to address the fractured experience in the Menlyn area. The project should respond to the poor connectivity and transport problems currently experienced in Menlyn and reinforce Menlyn as an important node within Tshwane. It is argued that a Platform Building at Menlyn could integrate the various transport systems present in the Menlyn precinct with the envisioned underground Gautrain station. / Dissertation (MArch(Prof))--University of Pretoria, 2012. / Architecture / unrestricted

The focus of this paper is platform theory, sharing economy, and user-centered design (UCD). Platform theory helps us understand the extensive research in its discourse and provides a stable ground to explore the fragile stage of platform emergence. The sharing economy is a central phenomenon to the studied project which is very important for our global use of future scarce resources. UCD is a central phenomenon where the importance of early involvement of users in the development process of a UCD project. By studying a platform project under development, I present an analytical framework where I identify vulnerabilities and difficulties in platform emergence. The emergence of platforms is an important yet difficult, and vulnerable process, and only a few studies have been conducted exploring this phase. The research question addressed in this thesis is: What are the sources to vulnerabilities and difficulties in the process of platform emergence? Methods of conducting this study are the use of semi-structured interviews of the people involved in the platform project for further flexibility of the questions. The case study project is focused on building a platform that enables users to build their own platforms. The purpose of that project is to enable users to create sharing platforms easier and cheaper. In addition, vulnerabilities and difficulties in platform emergence are explored. The goals of this study are to: 1) understand how a project is performing in this fragile stage of platform emergence, and 2) how to reach the goal where a platform with the underlying themes of platform theory, sharing economy, and user-centered design can be achieved.

Diversos ciudadanos de Lima tienen adversidades en los servicios básicos del hogar. Problemas comunes como el atoro de inodoros, una volada de fusible e inclusive daño que imposibilite realizar su vida de manera cotidiana. Así mismo, hay muchos trabajadores informales que pueden dar solución a estos problemas. Las cuales son personas que viven del día a día, y mientras más trabajo tenga, mejor calidad de vida podría alcanzar. Por ello, el objetivo de nuestro proyecto es conectar a estos dos segmentos, a través de una plataforma web, donde podrán encontrar personal capacitado para lo que se requiera. Los proveedores del servicio decidirán entre dos tipos de suscripciones mensuales; y por el lado de los clientes, pagarán una tarifa plana para la revisión de sus problemas. Se tiene la convicción de la viabilidad de este proyecto, basados en los resultados de la investigación de mercado, focus group, entrevistas a expertos y resultados del concierge. / Many citizens of Lima have adversities with the home basic services. These can get stuck, spoiled, even completely broken. And, on the other side, many informal workers that can give solutions to these problems. Which are people that lives up to a daily income; as much work they can make, they can achieve a better life quality. For that reason, this project intends to connect these two segments, through a web platform, where they can find the qualified technician it is needed. The providers of this service will choose between two option of subscription; meanwhile, the clients will pay a flat rate for the inspection of their problem. The team has the belief of the viability of this project, based on the results of the market investigation, focus group, interviews to experts and the concierge. / Trabajo de investigación

GetWork nace para atender tres segmentos de mercado enlazados entre sí. En primer lugar, empresas que necesiten cubrir plazas dentro de su equipo de trabajo y buscan a los profesionales más capacitados y sobretodo que les aseguren la creación de valor con su permanencia, atendiendo una problemática como la rotación de personal, y crecimiento dentro de la empresa. Por otro lado, profesionales con dificultades para encontrar el trabajo soñado, o simplemente con dificultades para integrarse al mercado laboral. Ante ello, GetWork garantiza apoyo y asesoría completa, inducción en diversos temas, consejos para la elaboración de CVs y presentación personal, etc. La meta final es que los profesionales se unan a empresas en las que puedan establecerse en una relación de beneficio mutuo. Por último, empresas dedicadas a la educación y capacitaciones para profesionales que se encuentran en la búsqueda de empleo, o que desean mejorar sus habilidades y aptitudes para alcanzar mayores rendimientos en sus centros de trabajo. Para ello, GetWork le sirve de ventana a estas instituciones para darse a conocer por medio de publicidad y conseguir nuevos clientes que eventualmente crearán valor no solo para las empresas en las que laboran, sino también para nosotros incrementado las posibilidades de nuestro servicio. / GetWork was created to serve the three following market segments: companies, users and institutions dedicated to education and training. First place, companies, with open jobs openings who look for the most qualified professionals and above all to ensure the creation of value with their retention. Also, GetWork helps professionals with difficulties to find jobs, land an adequate job opportunity. GetWork guarantees full support and advice, induction on various topics, advices for the preparation of resume and personal presentation, etc. The ultimate goal is for professionals to join companies in which they can establish a mutually beneficial relationship. Finally, GetWork aids companies dedicated to education and training professionals who want to improve their skills and abilities to achieve higher performance in their workplaces. For this, GetWork serves as a link to these institutions to become known through advertising and increase their posibilities for networking. / Trabajo de investigación

<div>Digital transformation greatly affects all segments of our society. There are three powerful trends unleashed by the digital revolution: machine, platform, and crowd. The first trend emphasizes that machine learning can either complements or supplements human capabilities, which leads to data-driven decision making. The second trend shows that value creation is moving from physical products to platforms (e.g., Uber and Airbnb) where network effects can have a great impact. The third trend is about the emergence of online crowds. Several good examples are crowdfunding platforms like Indiegogo and collaborative platforms such as Wikipedia. My research work studies these three trends from different aspects. </div><div><br></div><div>In the first project, we investigated how professional reviewers influence subsequent non-editor reviewers in their writing behaviors. Restaurants that receive editorial reviews are found to have reviewers who not only post more frequently, but also give lengthier and more neutral feedback. Further investigation of the mechanism finds that in terms of the topics, sentiment, and readability, following reviews of restaurants that receive editorial reviews become increasingly similar to their editorial reviews, indicating that a herding effect is the main driver of the shift in later reviews. In this study, we not only look at quantitative review characteristics such as rating and review length, but also extract qualitative review characteristics embedded in review text using Natural Language Processing (NLP) techniques (e.g., Topic modeling and Sentiment analysis). </div><div><br></div><div>In the second project, we studied how AI-based shelf monitoring can help manufacturers with their shelf management efforts. In general, we've discovered that AI-powered shelf monitoring boosts product sales. We further reveal that the positive effect shall be attributed to independent retailers rather than chained retailers. More broadly, the finding further suggests that AI-powered monitoring is more scalable, allowing manufacturers to cope more effectively with more heterogeneous objects. In this study, we analyzed shelf photos using deep learning (e.g., image recognition). Furthermore, we conducted a qualitative study (i.e., interviews) as a supplement attempt to uncover the underlying mechanism behind the interesting phenomenon found in our field experiment. </div><div><br></div><div>In the third project, we tried to understand the dynamic contribution patterns caused by backers’ multiple roles and fundraisers’ strategic behaviors. We show that projects described by more subjective content (i.e., title and introduction) significantly repel potential donors. We further show that fundraisers’ contribution to their own projects might increase donor’ intention to donate and has no significant impact on reward pledging of subsequent backers. Above that, we find a positive interplay between donation and reward pledge, suggesting a cross-channel peer influence that will facilitate the fundraising progress. </div>

Objective: To compare the tape cast, and an Air-Stirrup/closed basketweave combination to the Air-Stirrup alone with respect to their effects on dynamic ankle inversion. Design and Setting: This study used a repeated measures design with the independent variables being the exercise bout and the ankle support method (4 levels: no support, Air-Stirrup only, Air-Stirrup/closed basketweave, and tape cast). The 2 dependent variables were total inversion and maximum inversion velocity. Measurements were taken before and after an exercise bout, and all trials were conducted in the university's human performance laboratory. Subjects: 16 subjects (11 male, 5 female, age 24.3 ± 1.8 years) with no ankle injury within 6 months prior to participation participated in this study. Measurements: Subjects stood on an inversion platform, which rotated 37° in the frontal plane, creating dynamic inversion of the ankle. Total inversion and maximum inversion velocity were calculated using electrogoniometers. A linear growth curve was used to model pre to post exercise differences. Results: There was a significant difference between the control and the 3 support methods for both variables. The effects of the Air-Stirrup/closed basketweave were similar to the effects of the Air-Stirrup alone. There was no significant difference between the tape cast and the Air-Stirrup. Conclusions: All 3 support methods significantly reduce total ankle inversion and maximum inversion velocity. When compared with the Air-Stirrup alone, the tape cast and the tape/brace combination both are similar in their effects on total ankle inversion and maximum inversion velocity.