10 research outputs found
MQTT as control protocol for remote acces to industrial networks
[Resumen] El acceso remoto a redes industriales es una de las contribuciones que la Industria 4.0 ha popularizado al habilitarse la integración de las tecnologías TCP/IP en las redes OT y poder realizarse dicho acceso a través de la red pública Internet. De esa forma se posibilita ejecutar operaciones de mantenimiento de forma remota con mejoras en recursos y costes respecto a las opciones previas. No obstante, este acceso hace que los riesgos de seguridad aumenten al abrirse una nueva e importante vulnerabilidad y existir la posibilidad de acceso desde cualquier equipo conectado a Internet. Para poder gestionar de forma eficiente estos accesos remotos, este trabajo propone el uso del protocolo industrial de telemetría MQTT en el intercambio de comandos de control de acceso entre las partes implicadas. Ello permite una modalidad de acceso oportunista que disminuye cuantitivamente hasta en cuatro los niveles de seguridad requeridos según la norma IEC62443. La propuesta incluye una topología basada en tres elementos, el Ancla, el UNet y el Nauta y en tres servicios ofrecidos en formato Open-Source, el servicio de redirección de puertos, el servicio de acceso y el servicio de control de acceso.[Abstract] Remote access to industrial networks is one of the contributions that Industry 4.0 has popularized by enabling integration of TCP/IP technologies in OT networks and, therefore, to make industrial networks reachable using the public Internet. Remote maintenance is one of the great beneficiaries of this functionality. However, this access increases the security risks because a new and important vulnerability is opened by the possibility of remote access from any computer connected to the Internet. In order to fficiently manage these remote accesses, this paper proposes the use of the industrial telemetry protocol MQTT in the exchange of access control commands between the involved devices. This allows an opportunistic access modality that quantitatively reduces the security levels required by the IEC62443 standard by up to four. The proposal includes a topology based on three elements, the Anchor, the UNet and the Nauta and on three di erent services offered in Open-Source format; the port-redirection service, the access service and the access control service
Geological Factors and Health Problems
<p>Geological factors, such as damages, can cause health determinants in people, which were a little-studied and if they have been raised on occasion, usually referred to no communicable diseases. The aim of this work, which is a more or less updated bibliography, has been to develop a holistic idea for a better understanding of a problem and force latent or potential risk that they can carry and consider scientific basis infectious diseases especially complex. In essence, the focus of ecosystem health that should be considered in terrestrial ecosystems. It also provides the basic elements for the development of new research in this field.</p
Formación del profesorado en educación musical a través de enseñanza semipresencial: un estudio de casos
Temporal variation of sandy beach macrofauna at two sitest with distinct environmental conditions on Cassino beach, extreme southern Brazil
Temporal variations of the macrofauna of sandy beaches have been related to variations in the beach morphodynamics and also to the population dynamics of dominant species. The aim of this article is to describe the temporal variation of the intertidal macrofauna at two sites with distinct
environmental condition on Cassino Beach, extreme southern Brazil. At each site three transect lines 50 m apart were defined perpendicular to the shore line, from which samples were collected monthly in triplicate at 4 intertidal levels (10 m apart) from June 2004 to May 2005. During winter a generally
low density was observed, due to the absence of recruitments and to the mud deposition, which occurred just before sampling (in April 2004), and to low intensity stranding events. Spring witnessed a population explosion of Scolelepis gaucha, a migration of Mesodesma mactroides adults from the subtidal zone, and a strong stranding event. In the summer, recruitment of M. mactroides,Donax hanleyanus and Emerita brasiliensis was observed. Fall was characterized by low densities, except for D. hanleyanus recruitment. The macrofauna at both sites showed a striking seasonal variation in density and diversity, perhaps attributable to the recruitment of numerically dominant species and physical disturbances (stranding and mud deposition).Variações sazonais da macrofauna bentônica de praias arenosas têm sido relacionadas com variações da morfodinâmica da praia e também aos recrutamentos das espécies dominantes. Este trabalho objetiva avaliar a variabilidade temporal da macrofauna da zona entremarés de dois locais com distintas características ambientais na praia do Cassino, extremo sul do Brasil. Em cada local foram demarcadas três transversais (separadas por 50m) perpendiculares à linha de água, nas quais amostras foram coletadas em triplicata em 4 níveis entremarés (separados por 10 m), entre junho/2004 e maio/2005. Durante o inverno ocorreram baixas densidades da macrofauna, que foram relacionadas à
ausência de recrutamentos, à deposição de lama no mês de abril e à embancamentos de baixa intensidade. Na primavera foi registrada a explosão populacional de Scolelepis gaucha, migração de adultos de Mesodesma mactroides do infralitoral e um evento de embancamento. Durante o verão
destacaram-se os recrutamentos dos migradores mareais M. mactroides, Donax hanleyanus e Emerita brasiliensis. O outono foi caracterizado por baixas densidades, exceto pelo recrutamento de D.hanleyanus. A macrofauna bentônica nos dois locais mostrou variações sazonais na densidade e diversidade, que podem ser atribuídas ao recrutamento das espécies dominantes e a ocorrência de perturbações físicas (embancamento e depósito de lama)