RESUMO
As startups são empresas que apresentam modelos de negócios marcados pela inovação, rapidez, flexibilidade e alta capacidade de adaptação aos mercados. Atuando em diferentes setores socioeconômicos, elas prometem criar e transformar produtos e serviços. A emergência e disseminação dessas empresas ocorrem em um momento histórico de mudanças iniciadas a partir de 1970 e marcadas pelas crises geradas com o esgotamento do paradigma da sociedade urbano industrial. No Brasil, o número desse modelo de negócio apresentou uma expansão expressiva, alcançando a marca de 13.374 nos últimos cinco anos. Atento a esse cenário, o objetivo desta pesquisa consistiu em compreender como sujeitos, grupos e instituições atribuem sentidos à experiência de trabalho nas chamadas startups. Na parte teórica, as condições sociais e econômicas que possibilitaram a emergência e disseminação das startups são analisadas em uma perspectiva crítica. A parte empírica, por sua vez, apresenta depoimentos de empreendedores relatando o contexto geral de atuação nas startups. Ao final deste artigo, conclui-se que há uma instrumentalização capitalística de componentes subjetivos específicos selecionados e colocados em circulação para fortalecer o modo de produção capitalista financeirizado.(AU)
Startups are companies that have business models characterized by innovation, speed, flexibility, and a high capacity to adapt to markets. Operating in different socioeconomic sectors, they promise to create and transform products and services. The emergence and dissemination of these companies occur at a historical moment of changes that began from 1970 and are marked by the crises generated by the exhaustion of the paradigm of industrial urban society. In Brazil, the number of businesses in this model showed a significant expansion, reaching 13,374 companies in the last five years. Attentive to this scenario, the objective of this research was to understand how subjects, groups, and institutions attribute meanings to the work experience in so-called startups. In the theoretical part, the social and economic conditions that enabled the emergence and dissemination of startups are analyzed in a critical perspective. The empirical part presents entrepreneurs reporting the general context of action in startups. At the end of this article, it is concluded that there is a capitalistic instrumentalization of specific subjective components that are selected and put into circulation to strengthen the financed capitalist production.(AU)
Las startups son empresas que tienen modelos de negocio marcados por la innovación, la velocidad, la flexibilidad y una alta capacidad de adaptación a los mercados. Desde diferentes sectores socioeconómicos, las startups prometen crear y transformar productos y servicios. La aparición y difusión de estas empresas se produce en un momento histórico de cambios que comenzó a partir de 1970 y que está marcado por crisis generadas por el agotamiento del paradigma de la sociedad urbana industrial. En Brasil, estas empresas se expandieron significativamente alcanzando la marca de 13.374 empresas en los últimos cinco años. En este escenario, el objetivo de esta investigación fue entender cómo los sujetos, grupos e instituciones atribuyen significados a la experiencia laboral en las startups. En la parte teórica, se analizan las condiciones sociales y económicas que permitieron el surgimiento y la difusión de las startups en una perspectiva crítica. La parte empírica presenta testimonios de emprendedores que informan sobre el trabajo en startups. La investigación concluye que hay una instrumentalización capitalista de componentes subjetivos específicos que se seleccionan y ponen en circulación para fortalecer el modo de producción capitalista financiero.(AU)
Assuntos
Humanos , Masculino , Feminino , Satisfação Pessoal , Psicologia Social , Trabalho , Organizações , Capitalismo , Organização e Administração , Inovação Organizacional , Grupo Associado , Personalidade , Política , Corporações Profissionais , Prática Profissional , Psicologia , Relações Públicas , Gestão de Riscos , Segurança , Salários e Benefícios , Ajustamento Social , Mudança Social , Valores Sociais , Tecnologia , Pensamento , Jornada de Trabalho , Tomada de Decisões Gerenciais , Proposta de Concorrência , Financiamento de Capital , Inteligência Artificial , Conferências de Consenso como Assunto , Cultura Organizacional , Saúde , Pessoal Administrativo , Saúde Ocupacional , Técnicas de Planejamento , Adolescente , Empreendedorismo , Readaptação ao Emprego , Setor Privado , Modelos Organizacionais , Entrevista , Gestão da Qualidade Total , Gerenciamento do Tempo , Eficiência Organizacional , Comportamento Competitivo , Recursos Naturais , Comportamento do Consumidor , Serviços Contratados , Benchmarking , Patente , Serviços Terceirizados , Evolução Cultural , Marketing , Difusão de Inovações , Competição Econômica , Eficiência , Emprego , Eventos Científicos e de Divulgação , Comercialização de Produtos , Estudos de Avaliação como Assunto , Agroindústria , Planejamento , Ensaios de Triagem em Larga Escala , Empresa de Pequeno Porte , Rede Social , Administração Financeira , Invenções , Crowdsourcing , Computação em Nuvem , Equilíbrio Trabalho-Vida , Participação dos Interessados , Crescimento Sustentável , Liberdade , Big Data , Utilização de Instalações e Serviços , Comércio Eletrônico , Blockchain , Desenho Universal , Realidade Aumentada , Inteligência , Investimentos em Saúde , Meios de Comunicação de Massa , OcupaçõesRESUMO
With the fast development of blockchain technology in the latest years, its application in scenarios that require privacy, such as health area, have become encouraged and widely discussed. This paper presents an architecture to ensure the privacy of health-related data, which are stored and shared within a blockchain network in a decentralized manner, through the use of encryption with the RSA, ECC, and AES algorithms. Evaluation tests were performed to verify the impact of cryptography on the proposed architecture in terms of computational effort, memory usage, and execution time. The results demonstrate an impact mainly on the execution time and on the increase in the computational effort for sending data to the blockchain, which is justifiable considering the privacy and security provided with the architecture and encryption.
Assuntos
Blockchain , Privacidade , Atenção à Saúde , Algoritmos , Tecnologia , Segurança ComputacionalRESUMO
The rise of digitalization, sensory devices, cloud computing and internet of things (IoT) technologies enables the design of novel digital product lifecycle management (DPLM) applications for use cases such as manufacturing and delivery of digital products. The verification of the accomplishment/violations of agreements defined in digital contracts is a key task in digital business transactions. However, this verification represents a challenge when validating both the integrity of digital product content and the transactions performed during multiple stages of the DPLM. This paper presents a traceability method for DPLM based on the integration of online and offline verification mechanisms based on blockchain and fingerprinting, respectively. A blockchain lifecycle registration model is used for organizations to register the exchange of digital products in the cloud with partners and/or consumers throughout the DPLM stages as well as to verify the accomplishment of agreements at each DPLM stage. The fingerprinting scheme is used for offline verification of digital product integrity and to register the DPLM logs within digital products, which is useful in either dispute or violation of agreements scenarios. We built a DPLM service prototype based on this method, which was implemented as a cloud computing service. A case study based on the DPLM of audios was conducted to evaluate this prototype. The experimental evaluation revealed the ability of this method to be applied to DPLM in real scenarios in an efficient manner.
Assuntos
Blockchain , Internet das Coisas , Segurança Computacional , Computação em Nuvem , TecnologiaRESUMO
Maritime Domain Awareness (MDA) is a strategic field of study that seeks to provide a coastal country with an effective monitoring of its maritime resources and its Exclusive Economic Zone (EEZ). In this scope, a Maritime Monitoring System (MMS) aims to leverage active surveillance of military and non-military activities at sea using sensing devices such as radars, optronics, automatic Identification Systems (AISs), and IoT, among others. However, deploying a nation-scale MMS imposes great challenges regarding the scalability and cybersecurity of this heterogeneous system. Aiming to address these challenges, this work explores the use of blockchain to leverage MMS cybersecurity and to ensure the integrity, authenticity, and availability of relevant navigation data. We propose a prototype built on a permissioned blockchain solution using HyperLedger Fabric-a robust, modular, and efficient open-source blockchain platform. We evaluate this solution's performance through a practical experiment where the prototype receives sensing data from a Software-Defined-Radio (SDR)-based low-cost AIS receiver built with a Raspberry Pi. In order to reduce scalability attrition, we developed a dockerized blockchain client easily deployed on a large scale. Furthermore, we determined, through extensive experimentation, the client optimal hardware configuration, also aiming to reduce implementation and maintenance costs. The performance results provide a quantitative analysis of the blockchain technology overhead and its impact in terms of Quality of Service (QoS), demonstrating the feasibility and effectiveness of our solution in the scope of an MMS using AIS data.
Assuntos
Blockchain , Segurança Computacional , Humanos , Monitorização Fisiológica , Software , TecnologiaRESUMO
Lower renewable energy generator prices are leading people to install solar panels to reduce their electricity bills or, in some cases, even sell the surplus generated energy to the grid and earn credits from the grid operator. Generally, they are limited to trading the energy they generate with the grid company, which has a dominant role in price determination. Decentralized energy markets might increase both market competitiveness and incentive to further people's adoption of renewable energy, reducing security vulnerabilities and improving resiliency. Blockchain is a widely studied technology to provide decentralization for energy markets in this context. Scalability, privacy, market design, and user security are some of the open research topics. This work analyzes the literature related to blockchain and energy markets, proposes a model, implements it, performs experiments, and analyzes network scalability and data generation. The model, implemented with Hyperledger Fabric, enables validated clean energy trading with anonymized buyers to prevent consumption pattern exposure. The maximum transaction throughput was achieved with 5000 sensors, 5000 buyers, and 5000 sellers. The data generation rate by network and the baseline deployment costs were also analyzed to judge the network viability. Furthermore, this work provides empirical results on a topic that the literature lacks.
Assuntos
Blockchain , Humanos , Privacidade , TecnologiaRESUMO
Brazil was one of the largest cocoa producers in the world, mainly supported by the South of Bahia region. After the 1980s, the witch-broom disease demolished plantations, and farmers were forced into bankruptcy. The worldwide search for gourmet cocoa has rekindled interest in this production, whose fermentation process is a key step in obtaining fine cocoa, thanks to the fact that many processing properties and sensory attributes are developed in this phase. This article presents a blockchain-IoT-based system for the control and monitoring of these events, aiming to catalog in smart contracts valuable information for improvement of the cocoa fermentation process, and future research. Blockchain is used as a distributed database that implements an application-level security layer. A proof of concept was modeled and the performance of the emulated system was evaluated in the OMNet simulator, where a technique based on the SNMP protocol was applied to reduce the amount of data exchanged and resources served/consumed in this representation. Then, a physical platform was developed and preliminary experiments were performed on a real farm, as a way to verify the improvement of the cocoa fermentation process when using a technological approach.
Assuntos
Blockchain , Internet das Coisas , Brasil , Segurança Computacional , FermentaçãoRESUMO
BACKGROUND: The importance of blockchain-based architectures for personal health record (PHR) lies in the fact that they are thought and developed to allow patients to control and at least partly collect their health data. Ideally, these systems should provide the full control of such data to the respective owner. In spite of this importance, most of the works focus more on describing how blockchain models can be used in a PHR scenario rather than whether these models are in fact feasible and robust enough to support a large number of users. OBJECTIVE: To achieve a consistent, reproducible, and comparable PHR system, we build a novel ledger-oriented architecture out of a permissioned distributed network, providing patients with a manner to securely collect, store, share, and manage their health data. We also emphasize the importance of suitable ledgers and smart contracts to operate the blockchain network as well as discuss the necessity of standardizing evaluation metrics to compare related (net)works. METHODS: We adopted the Hyperledger Fabric platform to implement our blockchain-based architecture design and the Hyperledger Caliper framework to provide a detailed assessment of our system: first, under workload, ranging from 100 to 2500 simultaneous record submissions, and second, increasing the network size from 3 to 13 peers. In both experiments, we used throughput and average latency as the primary metrics. We also created a health database, a cryptographic unit, and a server to complement the blockchain network. RESULTS: With a 3-peer network, smart contracts that write on the ledger have throughputs, measured in transactions per second (tps) in an order of magnitude close to 102 tps, while those contracts that only read have rates close to 103 tps. Smart contracts that write also have latencies, measured in seconds, in an order of magnitude close to 101 seconds, while that only read have delays close to 100 seconds. In particular, smart contracts that retrieve, list, and view history have throughputs varying, respectively, from 1100 tps to 1300 tps, 650 tps to 750 tps, and 850 tps to 950 tps, impacting the overall system response if they are equally requested under the same workload. Varying the network size and applying an equal fixed load, in turn, writing throughputs go from 102 tps to 101 tps and latencies go from 101 seconds to 102 seconds, while reading ones maintain similar values. CONCLUSIONS: To the best of our knowledge, we are the first to evaluate, using Hyperledger Caliper, the performance of a PHR blockchain architecture and the first to evaluate each smart contract separately. Nevertheless, blockchain systems achieve performances far below what the traditional distributed databases achieve, indicating that the assessment of blockchain solutions for PHR is a major concern to be addressed before putting them into a real production.
Assuntos
Blockchain , Registros de Saúde Pessoal , Gerenciamento de Dados , Atenção à Saúde , HumanosRESUMO
In the Literature, we can find several research works to help in the digital crime fight in order to prove integrity and authenticity of a published document, image or video. Among all the crimes, fake news certainly is among the most recurrent ones and needs to be mitigated. There are several Blockchain-based applications in order to make use of the benefits derived from technology, but little is found to verify the authenticity of Web content records as well as the history of all updates that have taken place in each Web content. Such kind of solution has become important nowadays as a way to cover the gap in the combat against fake news, for example. The purpose of this paper is to present BlockProof, a framework for verifying web content authenticity and integrity that offers a solution for content providers to register Web content, regardless of whether the page has dynamic or static content, in addition to enabling the consultation of the history of all records made for a given URL. We understand that such kind of solution may be useful to data producers/providers to provide evidence that they are in compliance with the fight against fake news, for instance.
Assuntos
Blockchain , TecnologiaRESUMO
Personal health records (PHR) represent health data managed by a specific individual. Traditional solutions rely on centralized architectures to store and distribute PHR, which are more vulnerable to security breaches. To address such problems, distributed network technologies, including blockchain and distributed hash tables (DHT) are used for processing, storing, and sharing health records. Furthermore, fully homomorphic encryption (FHE) is a set of techniques that allows the calculation of encrypted data, which can help to protect personal privacy in data sharing. In this context, we propose an architectural model that applies a DHT technique called the interplanetary protocol file system and blockchain networks to store and distribute data and metadata separately; two new elements, called data steward and shared data vault, are introduced in this regard. These new modules are responsible for segregating responsibilities from health institutions and promoting end-to-end encryption; therefore, a person can manage data encryption and requests for data sharing in addition to restricting access to data for a predefined period. In addition to supporting calculations on encrypted data, our contribution can be summarized as follows: (i) mitigation of risk to personal privacy by reducing the use of unencrypted data, and (ii) improvement of semantic interoperability among health institutions by using distributed networks for standardized PHR. We evaluated performance and storage occupation using a database with 1.3 million COVID-19 registries, which showed that combining FHE with distributed networks could redefine e-health paradigms.
Assuntos
Blockchain , COVID-19 , Registros de Saúde Pessoal , Humanos , Registros Eletrônicos de Saúde , Confidencialidade , Segurança ComputacionalRESUMO
La internet de las cosas ha mantenido un crecimiento continuo en los últimos años. Las potencialidades de uso que muestra en diferentes campos han sido ampliamente documentadas. Su utilización efectiva en el campo de la salud puede traer consigo mejoras en la eficiencia de los tratamientos médicos, prevenir situaciones de riesgo, ayudar a elevar la calidad del servicio y proporcionar soporte a la toma de decisiones. La presente revisión profundiza en aspectos medulares de su utilización con el objetivo de explorar las principales tendencias y desafíos relacionados con la creciente utilización de la internet de las cosas en la salud, prestando mayor atención a los aspectos relacionados con las arquitecturas utilizadas para el despliegue de sistemas de internet de las cosas en ese ámbito, el manejo de la seguridad de estos sistemas y las herramientas para el apoyo a la toma de decisiones empleadas. Mediante el análisis documental se logra mostrar las principales características de estos sistemas, así como su arquitectura, herramientas utilizadas para la gestión de los datos capturados y mecanismos de seguridad. La utilización de la internet de las cosas en el campo de la salud tiene gran impacto, mejorando la vida de millones de personas en todo el mundo y brindando grandes oportunidades para el desarrollo de sistemas inteligentes de salud(AU)
The internet of things has maintained continuous growth in recent years. The potentialities of use that it shows in different fields have been widely documented. Its effective use in the field of health can bring improvements in the efficiency of medical treatments, prevention of risky situations, help raising the quality of service and provide support for decision-making. The present review explores into core aspects of its use in order to analyze trends, challenges and strengths. Document analysis was used to show the main characteristics of these systems, as well as their architecture, tools used for the management of the captured data and security mechanisms. The use of the internet of things in the health field has a great impact, improving the lives of millions of people around the world and providing great opportunities for the development of intelligent health systems(AU)