Integrated network experimentation for QoS measurements in opaque MANETs

Integrated network experimentation often combines real nodes with simulated ones, each modeling different portions of the topology, in the same experimental run. They enable new validation techniques and larger experiments than obtainable using real elements alone. Integrated experiments can be particularly useful in testing and validating QoS mechanisms for mobile ad hoc networks (MANETs), when the characteristics of the intermediate wireless network segments are not observable from the end segments, and as a consequence these intermediate segments have to be treated as opaque networks; and also when there is a need to conduct experiments in a real MANET environment at a scale larger than just a few nodes. End‐to‐end QoS assurance for such opaque networks, consisting of admission control and quality adjustment, can be based on techniques for dynamically measuring throughput representing the state of these networks. In this paper, we describe a distributed and hybrid testbed that has been deployed for running large‐scale integrated experiments to demonstrate the efficacy of a measurement‐based QoS solution. The infrastructure for the testbed provides an integrated platform consisting of real nodes running the actual software under test, augmented with a simulated network environment. We define a set of metrics and run experiments to evaluate the effectiveness of the QoS solution as well the performance of the deployed testbed. We propose an alternative architecture that employs a Xen‐based virtualization of the real nodes from the deployed testbed. We compare the performances of the virtualized architecture with the deployed architecture vis‐à‐vis latency and resource utilization. Our goal is to establish benchmarks for running large‐scale experiments on performance and QoS measurements in virtualized environments. Copyright © 2009 John Wiley & Sons, Ltd.     

Carbon Nanotube: Synthesis and Application in Solar Cell

Carbon nanotubes and fullerenes have a cylindrical and hollow spherical molecular structure with outstanding mechanical and electronic properties. Their versatility is outstanding and envisioned by the wide application range from field emission displays to impregnated metal composites, battery storage media, and nano-electronic devices. The combination of simple materials, diverse behavior, and ease of fabrication make these materials a cornerstone topic in current research. They have very wide applications in electronic devices and identifying the potential applications which is due to low bias transport at several nanometers. Since valance and conduction bands are symmetric, so they have a direct band gap and due to this it can be used in optical emission. CNTs can be synthesized via three techniques such as arc discharge, laser ablation and chemical vapor deposition, but the CVD process is mainly used for the synthesis because the CNT yield in such case will be more than 98 % pure. 100 % pure MWCNTs having multiple chirality results the enhanced optical property and better employment as light harvesting material. The dye sensitized solar cells are fabricated using CNT composites and functionalized nanotubes. The synthesis of CNT and its application in solar cell are presented in this short review.     

Speech and gesture analysis: a new approach

Multimedia Tools and Applications - Speech and gesture are interlinked components and are critical for felicitous communication. Both these components have certain characteristics, and when...     

Amorphous self-healed,chopped basalt fiber-reinforced,geopolymer composites

Geopolymer composites containing refractory, chopped basalt fibers and low-melting glass were made and systematically heat-treated at higher temperatures. Potassium-based geopolymer of stoichiometric composition K₂O·Al₂O₃·4SiO₂·11H₂O was produced by high shear mixing from fumed silica, deionized water, potassium hydroxide, (i.e., water glass) and metakaolin. With the addition of low-melting glass (T_m ~815°C) the flexure strengths of the composites increased to ~6 MPa after heat treatment above 900°C to 1100°C. A Weibull statistical analysis was performed showing how the amorphous self-healing effect of the glass frit significantly improved the flexure strength of the geopolymer and ceramic composites after high-temperature exposure. At temperatures up to 900°C, the geopolymer-basalt composite remained amorphous and the low-melting glass frit flowed into the dehydration cracks in the geopolymer matrix. This type of composite could be described as amorphous self-healed geopolymer (ASH-G). At ~1000°C, the geopolymer converted to primarily a crystalline leucite ceramic, but the basalt fiber remained intact, and the melted glass frit flowed and sealed the cracks developed at that temperature. This type of composite could then be described as amorphous self-healed ceramic (ASH-C). A temperature of 1150°C was determined to be optimum as at 1200°C the basalt fibers melted and the strength of the reinforcement was lost in the composites. The amorphous self-healing effect of the glass frit significantly improved the room temperature flexure strength of the heat-treated geopolymer-based composites.     

Plane strain problem in microstretch elastic solid

The eigenvalue approach is developed for the two-dimensional plane strain problem in a microstretch elastic medium. Applying Laplace and Fourier transforms, an infinite space subjected to a concentrated force is studied. The integral transforms are inverted using a numerical technique to get displacement, force stress, couple stress and first moment, which are also shown graphically. The results of micropolar elasticity are deduced as a special case from the present formulation.     

The augmented data vortex switch fabric: An all-optical packet switched interconnection network with enhanced fault tolerance

Optical Multistage Interconnection Networks (OMINs) are capable of transmitting terabits of bandwidth per second, and they have been considered as possible solutions to the electronic communications bottleneck in interconnection networks. A novel architecture, the Data Vortex (DV) switch, has been proposed by Yang et al., as a scalable, ultra low latency, ultra high capacity, high throughput, low cross-talk and low BER, all-optical packet switching fabric that is a suitable candidate for use as an OMIN. For any interconnection network, its fault tolerance and reliability are crucial issues, which have lacked attention up to now in the case for a DV switch. In this paper we, therefore, present results of fault tolerance and reliability analysis of the primary DV switch, and propose (1) a new Augmented Data Vortex (ADV) switch fabric, to improve the fault tolerance of the primary DV switch. (2) The labelling and a numbering scheme, with detailed interconnections of nodes for the ADV switch is given. (3) A new self-routing procedure and a priority scheme for distributed control signalling in the ADV switch have been given. (4) For the first time, conversion of the 3-dimensional switch to an equivalent chained-MIN model, has been given, which is more suitable for later analysis of fault tolerance. (5) A multiplexing scheme at input ports and output ports which further enhances the fault tolerance of the ADV switch has been given. (6) Computation has been done of the reliability and fault tolerance of the new architecture via an analytical model. (7) Finally, comparison of the ADV switch architecture with the primary architecture (DV) in view of fault tolerance and reliability has been given, and hardware complexity and cost effectiveness have been studied.     

Boron neutron-capture therapy (BNCT) for glioblastoma multiforme (GBM) using the epithermal neutron beam at the Brookhaven National Laboratory

OBJECTIVE: Boron neutron-capture therapy (BNCT) is a binary form of radiation therapy based on the nuclear reactions that occur when boron (10B) is exposed to thermal neutrons. Preclinical studies have demonstrated the therapeutic efficacy of p-boronophenylalanine (BPA)-based BNCT. The objectives of the Phase I/II trial were to study the feasibility and safety of single-fraction BNCT in patients with GBM. MATERIALS AND METHODS: The trial design required (a) a BPA biodistribution study performed at the time of craniotomy; and (b) BNCT within approximately 4 weeks of the biodistribution study. From September 1994 to July 1995, 10 patients were treated. For biodistribution, patients received a 2-hour intravenous (i.v.) infusion of BPA-fructose complex (BPA-F). Blood samples, taken during and after infusion, and multiple tissue samples collected during surgical debulking were analyzed for 10B concentration. For BNCT, all patients received a dose of 250 mg BPA/kg administered by a 2-hour i.v. infusion of BPA-F, followed by neutron beam irradiation at the Brookhaven Medical Research Reactor (BMRR). The average blood 10B concentrations measured before and during treatment were used to calculate the time of reactor irradiation that would deliver the prescribed dose. RESULTS: 10B concentrations in specimens of scalp and tumor were higher than in blood by factors of approximately 1.5 and approximately 3.5, respectively. The 10B concentration in the normal brain was < or = that in the blood; however, for purposes of estimating radiation doses to normal brain endothelium, it was always assumed to be equal to blood. BNCT doses are expressed as gray-equivalent (Gy-Eq), which is the sum of the various physical dose components multiplied to appropriate biologic effectiveness factors. The dose to a 1-cm3 volume where the thermal flux reached a maximum was 10.6 +/- 0.3 Gy-Eq in 9 patients and 13.8 Gy-Eq in 1 patient. The minimum dose in tumor ranged from 20 to 32.3 Gy-Eq. The minimum dose in the target volume (tumor plus 2 cm margin) ranged from 7.8 to 16.2 Gy-Eq. Dose to scalp ranged from 10 to 16 Gy-Eq. All patients experienced in-field alopecia. No CNS toxicity attributed to BNCT was observed. The median time to local disease progression following BNCT was 6 months (range 2.7 to 9.0). The median time to local disease progression was longer in patients who received a higher tumor dose. The median survival time from diagnosis was 13.5 months. CONCLUSION: It is feasible to safely deliver a single fraction of BPA-based BNCT. At the dose prescribed, the patients did not experience any morbidity. To further evaluate the therapeutic efficacy of BNCT, a dose-escalation study delivering a minimum target volume dose of 17 Gy-Eq is in progress.     

Sonographic detection of pneumoperitoneum: an experimental and clinical study

The sonographic appearance of intraperitoneal air collection has been studied in 46 patients. In 30 patients (group I), a pneumoperitoneum had been iatrogenically induced either during aspiration of ascitic fluid or during laparoscopy. Three normal volunteers (group II) had been subjected to graded intraperitoneal air injection to quantify the smallest amount of air detectable by ultrasound (US). In eight patients (group III) the sonographic demonstration of free intraperitoneal air led to a diagnosis of hollow visceral perforation; whereas in another five patients (group IV) the sonographic findings reinforced the clinical suspicion of a 'sealed off' perforation in the presence of negative roentgenograms. In all patients intraperitoneal air was seen as an echogenic line with a posterior reverberation or ring down artefact. In patients with free air, this was best seen in the perihepatic spaces with the patient in the supine, left lateral decubitus or prone position. As little as 5 mL of air could be consistently detected in all three volunteers (group II). Artefacts leading to a pseudopneumoperitoneum on US included; (i) the artefacts distal to an overlying rib; (ii) ring-down artefact from air in the adjacent lungs; and (iii) hepatodiaphragmatic interposition of colon. With proper sonographic technique and principles of interpretation these can be distinguished from true intraperitoneal air. Although sonography may be more informative than conventional radiology in patients with hollow visceral perforation, we did not find it more sensitive than conventional roentgenograms in detecting free intraperitoneal air. Sonography, however, is distinctly superior in patients with a sealed off perforation in whom conventional roentgenograms are frequently negative.     

Physicochemical and microbial quality evaluation of foam‐mat‐dried pineapple powder

Present experiments were carried to study the physicochemical and microbial quality of foam‐mat‐dried pineapple powder. Pineapple pulp was foamed using two foaming agents, tricalcium phosphate (TCP) (0%, 0.25%, 0.50%, 0.75%, and 1.0%) and egg white (EW) (0%, 0.50%, 1.0%, 1.50%, and 2.0%). Carboxy methyl cellulose (0.25%) was used as foam stabiliser, and drying was carried out at 65, 75, and 85 °C in tray drier followed by pulverising the dried foam mats in to fine powder. Powdered samples were analysed for various physicochemical quality parameters viz. total sugars, reducing sugars, ascorbic acid, total acid, pH, iron, phosphorus and calcium content, and bacterial and fungal load. Statistical analysis using LSD revealed that sample dried using 1% TCP at 65 °C was the best with 4.60% total sugars, 2.71% reducing sugars, 4.05 mg per 100 g ascorbic acid, 0.35% total acid, 0.29 mg per 100 g Iron, 2.24 mg per 100 g phosphorous, and 6.58 g per 100 g calcium and zero bacterial and fungal growth.     

A Process for the Separation of Phosphatide Mixtures: The Preparation of Phosphatidylethanolamine-free Phosphatides from Soya Lecithin

It is commonly accepted that phosphatidylcholine, phosphatidylethanolamine and phosphatidylinositol, the three major phosphatide constituents of soya lecithin are insoluble in acetone, and that extraction of the soya lecithin with acetone dissolves out the triglyceride oil and leaves a precipitate of a mixture of these three phosphatides. Intimate molecular association between phosphatides and acetone appears to be responsible for this. This paper presents a mechanistic picture for this association, discusses the means for preventing this association, and thereby dissolving phosphatides into acetone. A prospect for dissolving phosphatidylethanolamine into acetone, preferentially over others from a mixture, is thus opened up. This is important since it has practical applications in industry. It has been exploited by the development of a process for the separation of phosphatidylcholine and phosphatidylinositol (mixture) from commercial soya lecithin. The process solves a long standing industrial problem for the preparation of phosphatidylethanolamine-free phosphatides.