LightChain: A DHT-based Blockchain for Resource Constrained Environments

As an append-only distributed database, blockchain is utilized in a vast variety of applications including the cryptocurrency and Internet-of-Things (IoT). The existing blockchain solutions have downsides in communication and storage efficiency, convergence to centralization, and consistency problems. In this paper, we propose LightChain, which is the first blockchain architecture that operates over a Distributed Hash Table (DHT) of participating peers. LightChain is a permissionless blockchain that provides addressable blocks and transactions within the network, which makes them efficiently accessible by all the peers. Each block and transaction is replicated within the DHT of peers and is retrieved in an on-demand manner. Hence, peers in LightChain are not required to retrieve or keep the entire blockchain. LightChain is fair as all of the participating peers have a uniform chance of being involved in the consensus regardless of their influence such as hashing power or stake. LightChain provides a deterministic fork-resolving strategy as well as a blacklisting mechanism, and it is secure against colluding adversarial peers attacking the availability and integrity of the system. We provide mathematical analysis and experimental results on scenarios involving 10K nodes to demonstrate the security and fairness of LightChain. As we experimentally show in this paper, compared to the mainstream blockchains like Bitcoin and Ethereum, LightChain requires around 66 times less per node storage, and is around 380 times faster on bootstrapping a new node to the system, while each LightChain node is rewarded equally likely for participating in the protocol

Concepts and evolution of research in the field of wireless sensor networks

The field of Wireless Sensor Networks (WSNs) is experiencing a resurgence of interest and a continuous evolution in the scientific and industrial community. The use of this particular type of ad hoc network is becoming increasingly important in many contexts, regardless of geographical position and so, according to a set of possible application. WSNs offer interesting low cost and easily deployable solutions to perform a remote real time monitoring, target tracking and recognition of physical phenomenon. The uses of these sensors organized into a network continue to reveal a set of research questions according to particularities target applications. Despite difficulties introduced by sensor resources constraints, research contributions in this field are growing day by day. In this paper, we present a comprehensive review of most recent literature of WSNs and outline open research issues in this field

Organizational Structure and Resources of Alumni Associations at Public Senior Universities in the Southeastern United States

The purpose of the quantitative study was to analyze the staffing patterns, organizational structures, funding resources, practice of resource allocation, technology use, size of alumni population, size of institution enrollment, and age of the institutions at senior public colleges and universities in the southeastern United States. These institutions were derived from the membership of the Council for Advancement and Support of Education [CASE] during the academic years 2010-2012 in the United States District III region, generally the Southeast to lower Mid-Atlantic states. The study was further limited to public, comprehensive institutions as determined by the Carnegie Classification system. Data were collected through an online internet survey to test 11 research questions and gather demographic information relevant to the study. Of the 100 potential institutions for response, 16 completed surveys were received. The overall results of the tests reflect that 3 of the 11 results were statistically significant. Specifically, resource allocation scores were significantly higher than funding resource scores. Also there were strong positive correlations between technology use and age of institution and between size of alumni and the size of the institution

Joint ventures in the cable and videotex industries

Thesis (M.S.)--Massachusetts Institute of Technology, Sloan School of Management, 1984.MICROFICHE COPY AVAILABLE IN ARCHIVES AND DEWEY.Bibliography: leaves 202-213.by Thomas P. Caruso and Mark R. Harsch.M.S

Polidrone – Business Plan of a multipurpose modular drone produced via FDM

El TFG, realizado conjuntamente con la oficina I3P del Politécnico de Turín, constituye un Plan de Negocio para un dron creado y patentado por una serie de personas vinculadas al Politécnico de Turín con el fin de evaluar su viabilidad. La primera fase del Proyecto fue la definición de los casos de uso o nichos de mercado para los que iba destinado el dron. Para ello se tuvo que tener una absoluta comprensión mecánica del dron, destacando nuestras ventajas competitivas. También se realizó una serie de encuestas, entrevistas y análisis de mercado. Tomando como base los casos de uso elegidos, se realizó el Plan de Negocio completo. El cual analiza los puntos fuertes del dron, los segmentos y el tamaño de mercado, los clientes potenciales, la forma de comercialización, su distribución y venta, su promoción, fijar el precio, los proveedores, los materiales y equipos necesarios, su plan de financiación y beneficios esperados en 5 años, análisis de la competencia, etc. Finalmente, el Plan de Negocio fue presentado como concursante en una competición regional de proyectos innovadores. La START CUP Piemonte-Valle d’Aosta.Departamento de Ciencias de los Materiales e Ingeniería Metalúrgica, Expresión Gráfica en la Ingeniería, Ingeniería Cartográfica, Geodesia y Fotogrametría, Ingeniería Mecánica e Ingeniería de los Procesos de FabricaciónGrado en Ingeniería Mecánic