Transmission-line metamaterials based on complementary split-ring resonators (CSRRs) are shown to support forward, backward, electroinductive, and complex waves. Two CSRR-based lines are considered: ...1) stopband microstrip lines simply loaded with CSRRs, and 2) passband microstrip lines loaded with CSRRs and series gaps. The effects of interresonator coupling on bandwidth enhancement are analyzed on the basis of Bloch mode theory by considering the lumped-element equivalent 4-port circuit model of the unit cell. All the propagation modes are captured by the proposed multiterminal Bloch mode theory, from an eigenmode analysis. The results are validated through a commercial eigenmode solver and supported by experimental data.
Periosteal glomus tumor of the femur: A case report GONZALEZ-LLANOS, Francisco; LOPEZ-BAREA, Fernando; ISLA, Alberto ...
Clinical orthopaedics and related research,
11/2000, Letnik:
380, Številka:
380
Conference Proceeding, Journal Article
Recenzirano
Osseous abnormalities produced by glomus tumors located in soft tissues of the periungual region have been described. More rare is the location of a glomus tumor within bone, which usually is located ...in the phalanx of the fingers. However, to the authors' knowledge, there is no previous description of a glomus tumor located in a periosteal location of a long bone. A 50-year-old man with a glomus tumor in a periosteal location of the lower metaphysis of the femur without neoplastic erosion of the cortical surface is reported. Magnetic resonance imaging and intraoperative ultrasonography were needed to locate the lesion.
Over the past few years, approaches including artificial intelligence models into Wireless Sensor Networks have gained much attention within the research community. However, little attention has been ...paid to integrate Fuzzy Rule Based-Systems into Wireless Sensor Network. Since traditional approaches of Fuzzy Rule Based-Systems cannot be applied, due to limited resources that the sensors nodes have, the principal aim of this work is to design a distributed knowledge based Wireless Sensor Network, where each node of the network executes an adapted Fuzzy Rule Based-System. This aim has been divided into the followings: 1) to design a Fuzzy Rule Based-System adapted to a sensor node, 2) to design an application protocol which allows transmitting knowledge bases to sensors nodes and 3) to simulate a particular scenario with network simulator ns-2. The performance of a Sun SPOT sensor has been evaluated and a comparison to other devices is reported. The results show that a Sun SPOT sensor can execute properly a Fuzzy Rule Based-System adapted to it, and that it is possible to create a useful distributed knowledge based Wireless Sensor Network.
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► Use of a multi-agent architecture for wireless sensors. ► Duty time scheduling based on a fuzzy rule based system inside an intelligent agent. ► The duty time is adjusted by the ...results of the FRBS inference engine that takes variables from the real measures of the surrounding environment. ► This system can extend lifetime of battery for unattended remote measurement systems.
Wireless sensor networks comprise an important research area and a near future for industry and communications. Wireless sensor networks contain resource-constrained sensor nodes that are powered by small batteries, limited process and memory and wireless communication. These features give sensors their versatility and drawbacks, such as their limited operating lifetimes. To feasibly deploy wireless sensor networks with isolated motes, several approaches and solutions have been developed; the most common, apart from using alternative power sources such as solar panels, are those that put sensors to sleep for time periods established by the application. We thus propose a fuzzy rule-based system that estimates the next duty cycle, taking the magnitude being tested and battery charge as input. To show how it works, we compare an analytical delta system to our contribution. As an application to test both systems, a sound pressure monitoring application is presented. The results have shown that the fuzzy rule-based system better predicts the evolution of the magnitude by which errors committed by idle periods decrease. This work also shows that application-oriented duty cycle control can be an alternative for measuring systems, thus saving battery and improving sensor node lifetime, with a reasonable loss of precision.
This paper presents the techniques used to monitor radiation damage in the LHCb Tracker Turicensis during the LHC Runs 1 and 2. Bulk leakage currents in the silicon sensors were monitored ...continuously, while the full depletion voltages of the sensors were estimated at regular intervals by performing dedicated scans of the charge collection efficiency as a function of the applied bias voltage. Predictions of the expected leakage currents and full depletion voltages are extracted from the simulated radiation profile, the luminosity delivered by the LHC, and the thermal history of the silicon sensors. Good agreement between measurements and predictions is found.
This article describes a custom VHDL firmware implementation of a two-dimensional cluster-finder architecture for reconstructing hit positions in the new vertex pixel detector (VELO) that is part of ...the LHCb Upgrade. This firmware has been deployed to the existing FPGA cards that perform the readout of the VELO, as a further enhancement of the DAQ system, and will run in real time during physics data taking, reconstructing VELO hits coordinates on-the-fly at the LHC collision rate. This pre-processing allows the first level of the software trigger to accept an 11% higher rate of events, as the ready-made hit coordinates accelerate the track reconstruction and consumes significantly less electrical power. It additionally allows the raw pixel data to be dropped at the readout level, thus saving approximately 14% of the DAQ bandwidth. Detailed simulation studies have shown that the use of this real-time cluster finding does not introduce any appreciable degradation in the tracking performance in comparison to a full-fledged software implementation. This work is part of a wider effort aimed at boosting the real-time processing capability of HEP experiments by delegating intensive tasks to dedicated computing accelerators deployed at the earliest stages of the data acquisition chain.
Although many studies have focused on testing computer networks under realistic traffic loads by means of genetic algorithms (GAs), little attention has been paid to optimising the parameters of the ...GAs in this problem. The objective of this work is to design and validate a system that, given some constraints on traffic bandwidth, generates the worst-case traffic for a given computer network and finds the traffic configuration (critical background traffic) that minimises throughput in that computer network. The proposed system is based on a meta-GA, which is combined with an adaptation strategy that finds the optimum values for the GA control parameters and adjusts them to improve the GA's performance. To validate the approach, different comparisons are performed with the goal of assessing the acceptable optimisation power of the proposed system. Moreover, a statistical analysis was conducted to ascertain whether differences between the proposed system and other algorithms are significant. The results demonstrate the effectiveness of the system and prove that, when the background traffic is driven by a GA that uses the parameters obtained from the system, the computer network's performance is much lower than when the traffic is generated by Poisson statistical processes or by other algorithms. This system has identified the worst traffic pattern for the protocol under analysis.
Although many studies have focused on testing computer networks under realistic traffic loads by means of genetic algorithms (GAs), little attention has been paid to optimising the parameters of the ...GAs in this problem. The objective of this work is to design and validate a system that, given some constraints on traffic bandwidth, generates the worst-case traffic for a given computer network and finds the traffic configuration (critical background traffic) that minimises throughput in that computer network. The proposed system is based on a meta-GA, which is combined with an adaptation strategy that finds the optimum values for the GA control parameters and adjusts them to improve the GA's performance. To validate the approach, different comparisons are performed with the goal of assessing the acceptable optimisation power of the proposed system. Moreover, a statistical analysis was conducted to ascertain whether differences between the proposed system and other algorithms are significant. The results demonstrate the effectiveness of the system and prove that, when the background traffic is driven by a GA that uses the parameters obtained from the system, the computer network's performance is much lower than when the traffic is generated by Poisson statistical processes or by other algorithms. This system has identified the worst traffic pattern for the protocol under analysis.
Extraadrenal paragangliomas involving the spinal cord are not common and usually take the compression of the cauda equine. Two cases of paraganglioma of the cauda equina with a different presentation ...are reported, and the clinical and histopathology findings of this tumor, as well as diagnosis, treatment and prognosis are review. We stress the importance of the high tumor vascularization form of intradural that can make impossible achieve a complete resection. Laminotomy and intraoperatory echography are very useful in the approach to intradural tumors, such as paraganglioma.
