660 resultados para UDP(userdatagramprotocol)Lite
Resumo:
In mid-July 2003, the U.S. Army Tank-Automotive & Armaments Command (TACOM) performed a series of experiments at Keweenaw Research Center (KRC), with a remote operated mine roller system. This system, named Panther Lite, consists of two M113 Armored Personnel Carriers (APC’s) connected by a Tandem Vehicle Linkage Assembly (TVLA). The system has three sets of mine rollers, two of which are connected to the front of the lead vehicle with one set trailing from the trail vehicle. Currently, the system requires two joystick controllers. One regulates the braking of the tracks, throttle, and transmission of the lead vehicle and the other controls the braking and throttle of the rear vehicle. One operator controls both joysticks, attempting to maneuver the lead vehicle along a desired path. At the same time, this operator makes compensation maneuvers to reduce lateral loads in the TVLA and to guide the rear mine rollers along the desired path. The purpose of this project is to create algorithms that would allow the slave (trail) vehicle to operate using inputs that maneuver the control (lead) vehicle. The project will be completed by first reconstructing the experimental data. Kinematic models will be generated and simulations created. The models will then be correlated with the reconstructions of the experimental data. The successful completion of this project will be a first step to eliminating the need for the second joystick.
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To interconnect a wireless sensor network (WSN) to the Internet, we propose to use TCP/IP as the standard protocol for all network entities. We present a cross layer designed communication architecture, which contains a MAC protocol, IP, a new protocol called Hop-to-Hop Reliability (H2HR) protocol, and the TCP Support for Sensor Nodes (TSS) protocol. The MAC protocol implements the MAC layer of beacon-less personal area networks (PANs) as defined in IEEE 802.15.4. H2HR implements hop-to-hop reliability mechanisms. Two acknowledgment mechanisms, explicit and implicit ACK are supported. TSS optimizes using TCP in WSNs by implementing local retransmission of TCP data packets, local TCP ACK regeneration, aggressive TCP ACK recovery, congestion and flow control algorithms. We show that H2HR increases the performance of UDP, TCP, and RMST in WSNs significantly. The throughput is increased and the packet loss ratio is decreased. As a result, WSNs can be operated and managed using TCP/IP.
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The exact mechanism for capillary occlusion in diabetic retinopathy is still unclear, but increased leukocyte-endothelial cell adhesion has been implicated. We examined the possibility that posttranslational modification of surface O-glycans by increased activity of core 2 transferase (UDP-Glc:Galbeta1-3GalNAcalphaRbeta-N-acetylglucoaminyltr ansferase) is responsible for increased adhesion of leukocytes to vascular endothelium in diabetes. The mean activity of core 2 transferase in polymorphonuclear leukocytes isolated from type 1 and type 2 diabetic patients was higher compared with age-matched control subjects (1,638 +/- 91 [n = 42] vs. 249 +/- 35 pmol x h(-1) x mg(-1) protein [n = 24], P = 0.00013; 1,459 +/- 194 [n = 58] vs. 334 +/- 86 [n = 11], P = 0.01). As a group, diabetic patients with retinopathy had significantly higher mean activity of core 2 transferase compared with individuals with no retinopathy. There was a significant association between enzyme activity and severity of retinopathy in type 1 and type 2 diabetic patients. There was a strong correlation between activity of core 2 transferase and extent of leukocyte adhesion to cultured retinal capillary endothelial cells for diabetic patients but not for age-matched control subjects. Results from transfection experiments using human myelocytic cell line (U937) demonstrated a direct relationship between increased activity of core 2 transferase and increased binding to cultured endothelial cells. There was no relationship between activity of core 2 transferase and HbA(1c) (P = 0.8314), serum advanced glycation end product levels (P = 0.4159), age of the patient (P = 0.7896), and duration of diabetes (P = 0.3307). On the basis that branched O-glycans formed by the action of core 2 transferase participate in leukocyte adhesion, the present data suggest the involvement of this enzyme in increased leukocyte-endothelial cell adhesion and the pathogenesis of capillary occlusion in diabetic retinopathy.
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Integrating physical objects (smart objects) and enterprise IT systems is still a labor intensive, mainly manual task done by domain experts. On one hand, enterprise IT backend systems are based on service oriented architectures (SOA) and driven by business rule engines or business process execution engines. Smart objects on the other hand are often programmed at very low levels. In this paper we describe an approach that makes the integration of smart objects with such backends systems easier. We introduce semantic endpoint descriptions based on Linked USDL. Furthermore, we show how different communication patterns can be integrated into these endpoint descriptions. The strength of our endpoint descriptions is that they can be used to automatically create REST or SOAP endpoints for enterprise systems, even if which they are not able to talk to the smart objects directly. We evaluate our proposed solution with CoAP, UDP and 6LoWPAN, as we anticipate the industry converge towards these standards. Nonetheless, our approach also allows easy integration with backend systems, even if no standardized protocol is used.
Resumo:
Various applications for the purposes of event detection, localization, and monitoring can benefit from the use of wireless sensor networks (WSNs). Wireless sensor networks are generally easy to deploy, with flexible topology and can support diversity of tasks thanks to the large variety of sensors that can be attached to the wireless sensor nodes. To guarantee the efficient operation of such a heterogeneous wireless sensor networks during its lifetime an appropriate management is necessary. Typically, there are three management tasks, namely monitoring, (re) configuration, and code updating. On the one hand, status information, such as battery state and node connectivity, of both the wireless sensor network and the sensor nodes has to be monitored. And on the other hand, sensor nodes have to be (re)configured, e.g., setting the sensing interval. Most importantly, new applications have to be deployed as well as bug fixes have to be applied during the network lifetime. All management tasks have to be performed in a reliable, time- and energy-efficient manner. The ability to disseminate data from one sender to multiple receivers in a reliable, time- and energy-efficient manner is critical for the execution of the management tasks, especially for code updating. Using multicast communication in wireless sensor networks is an efficient way to handle such traffic pattern. Due to the nature of code updates a multicast protocol has to support bulky traffic and endto-end reliability. Further, the limited resources of wireless sensor nodes demand an energy-efficient operation of the multicast protocol. Current data dissemination schemes do not fulfil all of the above requirements. In order to close the gap, we designed the Sensor Node Overlay Multicast (SNOMC) protocol such that to support a reliable, time-efficient and energy-efficient dissemination of data from one sender node to multiple receivers. In contrast to other multicast transport protocols, which do not support reliability mechanisms, SNOMC supports end-to-end reliability using a NACK-based reliability mechanism. The mechanism is simple and easy to implement and can significantly reduce the number of transmissions. It is complemented by a data acknowledgement after successful reception of all data fragments by the receiver nodes. In SNOMC three different caching strategies are integrated for an efficient handling of necessary retransmissions, namely, caching on each intermediate node, caching on branching nodes, or caching only on the sender node. Moreover, an option was included to pro-actively request missing fragments. SNOMC was evaluated both in the OMNeT++ simulator and in our in-house real-world testbed and compared to a number of common data dissemination protocols, such as Flooding, MPR, TinyCubus, PSFQ, and both UDP and TCP. The results showed that SNOMC outperforms the selected protocols in terms of transmission time, number of transmitted packets, and energy-consumption. Moreover, we showed that SNOMC performs well with different underlying MAC protocols, which support different levels of reliability and energy-efficiency. Thus, SNOMC can offer a robust, high-performing solution for the efficient distribution of code updates and management information in a wireless sensor network. To address the three management tasks, in this thesis we developed the Management Architecture for Wireless Sensor Networks (MARWIS). MARWIS is specifically designed for the management of heterogeneous wireless sensor networks. A distinguished feature of its design is the use of wireless mesh nodes as backbone, which enables diverse communication platforms and offloading functionality from the sensor nodes to the mesh nodes. This hierarchical architecture allows for efficient operation of the management tasks, due to the organisation of the sensor nodes into small sub-networks each managed by a mesh node. Furthermore, we developed a intuitive -based graphical user interface, which allows non-expert users to easily perform management tasks in the network. In contrast to other management frameworks, such as Mate, MANNA, TinyCubus, or code dissemination protocols, such as Impala, Trickle, and Deluge, MARWIS offers an integrated solution monitoring, configuration and code updating of sensor nodes. Integration of SNOMC into MARWIS further increases performance efficiency of the management tasks. To our knowledge, our approach is the first one, which offers a combination of a management architecture with an efficient overlay multicast transport protocol. This combination of SNOMC and MARWIS supports reliably, time- and energy-efficient operation of a heterogeneous wireless sensor network.
Resumo:
Multiple osteochondromas (also called hereditary multiple exostoses) is an autosomal dominant disorder characterized by multiple cartilaginous tumors, which are caused by mutations in the genes for exostosin-1 (EXT1) and exostosin-2 (EXT2). The goal of this study was to elucidate the genetic alterations in a family with three affected members. Isolation of RNA from the patients' blood followed by reverse transcription and PCR amplification of selected fragments showed that the three patients lack a specific region of 90 bp from their EXT1 mRNA. This region corresponds to the sequence of exon 8 from the EXT1 gene. No splice site mutation was found around exon 8. However, long-range PCR amplification of the region from intron 7 to intron 8 indicated that the three patients contain a deletion of 4318 bp, which includes exon 8 and part of the flanking introns. There is evidence that the deletion was caused by non-homologous end joining because the breakpoints are not located within a repetitive element, but contain multiple copies of the deletion hotspot sequence TGRRKM. Exon 8 encodes part of the active site of the EXT1 enzyme, including the DXD signature of all UDP-sugar glycosyltransferases. It is conceivable that the mutant protein exerts a dominant negative effect on the activity of the EXT glycosyltransferase since it might interact with normal copies of the enzyme to form an inactive hetero-oligomeric complex. We suggest that sequencing of RNA might be superior to exome sequencing to detect short deletions of a single exon.
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Se analizara brevemente la explotación extractiva yerbatera en la región Altoparanaense, del extremo norte al igual que en la vecina área del “Contestado” controladas por Brasil luego del laudo Cleveland. El problema de la ocupación de tierras por pequeños y medianos agricultores en oposición al sistema extractivo de las grandes compañías yerbateras que utilizaban el trabajo a destajo. La utilización de la mano de obra indígena y criolla fue un elemento importante que las grandes empresas intentaron resolver para asegurarse la continuidad del proceso extractivo yerbatero. La Compañía Matte Larangeira fue desde sus comienzos una de las más representativas y poderosas empresas con una “élite regional” que influyó en un amplio espacio geográfico transfronterizo.
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Este trabajo reflexiona acerca del momento constitutivo del modelo agroindustrial en Mendoza siguiendo las acciones que emprende la elite local de fines del siglo XIX para promoverlo. Basado en el planteo shumpeteriano sobre la importancia de los empresarios con respecto a la innovación para el desarrollo y el análisis de H. Nochteff sobre las carencias de políticas de ciencia y tecnología que caracterizan la economía Argentina como de adaptación tardía, se establecen una serie de diferenciaciones que colaboran a explicar el recorrido específico de la economía mendocina en su deriva pasada y actual frente el dominante patrón de acumulación nacional.
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Estanislao Zeballos creó un denso corpus teórico sobre las relaciones de la Argentina con sus vecinos, especialmente con Brasil y Chile. A lo largo del siglo XX, la élite intelectual rioplatense ha mantenido en vigencia el pensamiento de Zeballos, al cual se lo ha considerado una suerte de paradigma del patriota. El presente artículo examina críticamente el pensamiento de Zeballos. Detecta que, fuertemente marcadas por el positivismo y el darwinismo social, sus ideas se deslizaron hacia posiciones xenófobas y racistas, sobre todo hacia los dos países citados. Por tal motivo, el canciller generó conflictos de límites que antes no existían, y promovió conceptos históricamente inexactos sobre la naturaleza de las relaciones internacionales en el Cono Sur.
Resumo:
La ponencia se centra en el programa de la revista argentina Proa (2a época, 1924-1926). Enfoca su estrategia de promoción de una élite intelectual moderna encabezada por la figura del artista para la fundación de una "República de las letras" autónoma y de proyección internacional. En ese aspecto, Proa muestra su adscripción a una tradición elitista, espiritualista y juvenilista instalada con el Modernismo en el Río de la Plata hacia 1900. La reedición de esa ideología en una revista que propiciaba lo nuevo buscó consolidar un espacio literario a partir del cual promover una élite con aspiraciones de poder espiritual laico. Tomando como fuentes el epistolario de Güiraldes y algunos textos publicados en Proa se exponen acá algunos de los principales rasgos de ese programa, a partir de la autorrepresentación de sus escritores, del tipo de interpelación que propusieron y de su relación imaginaria con la sociedad.
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El presente trabajo se enmarca en un proyecto de investigación en proceso de elaboración, que trata sobre la política de las orquestas infanto juveniles en la Ciudad Autónoma de Buenos Aires y en la Provincia de Buenos Aires, dirigidas a la población de niños y jóvenes en situación de empobrecimiento. Nos proponemos abordar la relación entre lo culto y lo popular, y analizar los dispositivos de producción, reproducción, distinción, y diferenciación que podemos encontrar en los contenidos de las relaciones sociales en dicho espacio. Para la caracterización del vínculo entre lo culto y lo popular se tendrá en cuenta la situación actual del capitalismo global, el rol del Estado, su tratamiento de la cuestión social, así como las prácticas y representaciones de quienes llevan a cabo el proyecto. El abordaje es cualitativo, está basado en la revisión y análisis de bibliografía específica, e incluye resultados preliminares del trabajo de campo efectuado en el marco de la investigación
Resumo:
A partir de un discurso anclado en la necesidad de modernización cultural e institucional, el campo letrado de la primera mitad del siglo XIX establece nuevas formas de intervención pública en procura de captar (y mediar con) los diversos intereses del público lector. Las nuevas promociones letradas intentan llevar adelante esa tarea en los intersticios dejados por la prensa política y doctrinaria, reformulando su relación con el espacio público, y apelando a una serie de géneros menores (crónicas de moda, artículos satíricos, relatos de costumbres) que dialogan con las formas emergentes del mercado, la lógica del consumo, los temas "banales", etc. Ese nuevo emplazamiento permite revisar los modos en que la élite letrada diagramó sus proyectos literarios, culturales y políticos en el marco de las publicaciones periódicas de la primera mitad del siglo XIX.
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Análisis del discurso de la élite porteña, entre finales del siglo XVIII y principios del siglo XIX, en torno a la aparición de los sectores populares, como vehículo de legitimación política
Resumo:
En los villancicos a San Pedro Nolasco, Sor Juana combina una variante alta del latín de la época -el epígrafe (Mateo, 22, 20-21) de la dedicatoria a la Virgen- con una variante baja -los "latinajos" de un bachiller en la ensaladilla-. Tomando como marco teórico el modelo de Ferguson, se advierte que el factor determinante de esta diglosia es la oposición funcionalidad/disfuncionalidad de cada variante en su contexto respectivo. El examen de las connotaciones de esa oposición permite entender esta singular diglosia latina como manifestación de las tensiones entre cultura popular y cultura de élite, propias del villancico religioso.
Resumo:
Una de los efectos de la modernización fue la emergencia de un público urbano y el consecuente desarrollo de géneros menores vinculados con la novela por entregas y con las fórmulas estilizadas de la poesía gauchesca. De esta manera, el problema suscitado por el tipo de lengua que debe ser el modelo de la lengua de la literatura puede ser entendido como parte de la reacción de la élite intelectual frente al denominado criollismo-moreirismo. Este trabajo indagará los diferentes matices de esta reacción de la élite letrada en El problema del idioma nacional y El criollismo en la literatura argentina de Ernesto Quesada, las poesías de Rafael Obligado y La Guerra Gaucha de Leopoldo Lugones. Se insistirá más que nada en las diversas soluciones al problema de la lengua literaria y el idioma nacional, suscitado justamente por la contaminación de la lengua oral.