Neutron Diffraction Studies on Chemical and Magnetic Structure of Multiferroic PbFe0.67W0.33O3

We report on the single phase synthesis and room temperature structural characterization of PbFe0.67W0.33O3 (PFW) multiferroic. The PFW was synthesized by low temperature sintering, Columbite method. Analysis of powder XRD pattern exhibits single phase formation of PFW with no traces of pyrochlore phase. Detailed analysis of room temperature neutron diffraction (ND) reveals cubic phase at room temperature, space group Pm-3m. The ND pattern clearly reveals magnetic Bragg peak at 2theeta = 18.51 (Q = 1.36{\AA}-1). The refinement of magnetic structure reveals G-type antiferromagnetic structure in PFW at room temperature. The dielectric constant and loss tangent decreases with increasing frequency. The room temperature P-E measurements shows a non-linear slim hysteresis, typical nature of relaxor multiferroics, with saturation and remnant polarizations of Ps = 1.50 microC/cm2 and Pr = 0.40 microC/cm2, respectively.Comment: 3 pages, 5 figures, conferenc

Best Effort MPI/RT as an Alternative to MPI: Design and Performance Comparison

The Real-Time Message Passing Interface (MPI/RT) is an emerging real-time communications middleware standard for distributed real-time applications. The Message Passing Interface (MPI) is the de facto standard for high performance parallel application development. In this thesis, we describe how MPI/RT with best effort quality of service can be used as an alternative for MPI. Mercury Computer Systems\u27 RACE embedded parallel computer is used as the platform for comparison of design and performance of these two standards. The main advantages MPI/RT has over MPI are its explicit support for communication channels and its emphasis on early binding. Design and implementation of best effort MPI/RT on Mercury is described and its performance is compared with MPI in order to illustrate how MPI/RT features allow implementations to exploit the underlying platform more optimally. The results for the benchmarks show that MPI/RT outperforms MPI in almost all cases examined

INVESTIGATING THE EFFICACY OF VOCAL FUNCTION EXERCISES IN IMPROVING VOCAL FUNCTION IN ADULTS IRRADIATED FOR LARYNGEAL CANCERS: A THREE PART DISSERTATION

Deterioration in voice quality following radiation therapy for the treatment of laryngeal cancers (LC) is well documented in literature. The majority of studies show that these voice problems are long term and in some cases permanent. Deterioration in voice quality, especially over a period of time could lead to significant communication difficulties in daily life or in some cases could even result in loss of profession. Despite the negative effects of radiation therapy on voice quality being well documented, few studies have focused on the efficacy of voice therapy in the irradiated LC population. The purpose of this study was to investigate the efficacy of a well researched, evidence based voice therapy approach, known as Vocal Function Exercises (VFEs) in improving vocal function in patients who have been irradiated for LCs. The present study conducted in three systematic stages with distinct and related study aims. The first involved characterizing the head and neck cancer treatment seeking population at the University of Kentucky (UK). Stage 2 involved characterizing vocal function following irradiation for LC using a multidimensional assessment approach. Stage 3 was a phase 2 clinical trial aimed at treating these deficits in vocal function identified through stage 2 using a systematic evidence based voice therapy approach, Vocal Function Exercises. For the phase 2 clinical trial, the comparison group received vocal hygiene (VH) counseling. Observations from stage 1 showed that majority of patients from the treatment seeking population at UK between a 3 year time period from 2008 to 2010 were diagnosed with laryngeal cancers and were treated with chemoradiation therapy. Stage 2 demonstrated a multidimensional deterioration in vocal function following radiation therapy for laryngeal cancers. Stage 3 demonstrated a significant improvement in vocal function across the primary outcome measure (Voice Handicap Index) as a result of VFE+VH. Improvements were also seen in select parameters across the five domains of voice assessment in the VFE group. No significant improvements were observed in the vocal hygiene group in any parameters in each domain of voice assessment. Our study demonstrated adults irradiated for laryngeal cancers demonstrated a multi-dimensional deterioration of vocal function. These changes were long term since study participants were 2- 7 years post radiation therapy. Implementation of VFE+VH demonstrated a significant improvement in voice related quality of life and select parameters across the five domains of voice assessment. The present study demonstrated promising preliminary evidence for the use of VFE+VH to improve vocal function in patients irradiated for laryngeal cancers

Increased Persistence of Wi-Fi Direct Networks for Smartphone-based Collision Avoidance

Inter-vehicular communication is a promising technology to improve road safety. Inter-vehicular communication over a wireless medium can be used to exchange important information such as the speed, location, and headings of a vehicle with nearby vehicles. Using this information, it is possible to calculate if a collision is imminent and warn the driver to take action. Wi-Fi can also be used to share this information, however it requires an access point hardware to facilitate communication. Wi-Fi Direct enabled devices can share information without a hardware access point. Wi-Fi Direct provides peer to peer communication by employing a software defined access point embedded within the system. Wi-Fi Direct is a technology that is present on many smart phones, eliminating the need for dedicated access point hardware. In collision avoidance application, Wi-Fi Direct maybe used to exchange safety-related information between vehicles. Collision avoidance systems developed using smartphones can also be extended to protecting pedestrians carrying a smartphone and in this role they could be a long-term solution for certain vulnerable road user collision scenarios. Smartphones with Wi-Fi Direct capability could provide a path to early, low-cost implementation of inter-vehicle communication for collision avoidance. However, there are many limitations to such a system that are addressed in this thesis. Wi-Fi Direct functions by creating groups. One of the nodes in the group is elected as the group owner that acts as an access point and manages the communication between the nodes within the group. If the group owner moves out of range, reforming the group is a lengthy process. This thesis proposes a new method for nomination of the group owner to reduce the likelihood that the group owner will move out of range. This thesis introduces the concept of nominating a Backup Group Owner that can quickly replace the group owner if the group owner shuts down or moves out of range of the group. An orderly handoff from the group owner to the Backup Group Owner can prevent loss of communication among nodes. An analytical study of the amount of time saved by adopting the proposed method of electing the BGO is presented

Improvement in flowability of thermo-chemical storage material by using nanostructured additives

Thermal energy storage is an advancing technology for storing energy that encourages clean energy systems without adversely affecting the environment. This technology allows us to use energy at different times by storing it temporarily. For example in a non-conventional energy source like solar thermal power plant, all its energy is produced during broad day light. The excess energy produced during a sunny day is usually stored in the thermal storage materials, which can later be used in the night to generate electricity. One such advantageous way of storing energy is through thermo-chemical storage. In a space craving society, high storage capability makes it an efficient way to store energy. However at present thermo-chemical storage is in its elementary stage, where in its limited to only one pilot scale system. Considering the thermodynamics and kinetics it has been shown that CaO/Ca(OH)2 reaction system is a potential gas/solid thermochemical heat storage system. However the behavior in a lab sized non-moving bed reactor was mainly dominated by heat and mass transfer limitations arising due to small particle size and changes in bulk properties. This was overcome to a certain level using a moving bed reactor but due to the change in the reactor type the flowability factor dominated adversely. Nevertheless during the recent studies at DLR it was found out that small amount of industrial grade SiO2 (Aerosil®) nanoparticles would enhance the flowability of Ca(OH)2 in a considerable way. But in contrast it effects the heat development leading to low thermal efficiency due to the formation of inert side products. In this study it is found out that small amount of nanostructured Al2O3 (Aeroxide®) not only plays a significant role in stabilizing cyclability and bulk properties but also contributes to the overall heat development

Canola and mustard response to short periods of high temperature and drought stresses at different growth stages

Non-Peer ReviewedBrassica crops grown on the semiarid Canadian prairie are often subject to heat and water stress during the period of flowering. A growth chamber study was conducted at Swift Current to understand the effects of short periods of high temperature stress and/or water stress at different developmental stages on the seed yield formation of different Brassica species. Two advanced breeding lines of canola quality Brassica juncea (PC98-44 and PC98-45) along with a canola cv. Quantum (B. napus L.) and a mustard cv. Cutlass (B. juncea L.) were grown under 20/18 °C day/night temperature. High (35/18 °C) and low (28/18 °C) temperature stresses were imposed for 10 days at bolting, flowering or pod formation stages in two separate growth cabinets. At the same time, low (90% available water) or high (50% available water) water stress was imposed on half of the plants in each of the temperature treatments. All yield components were affected by temperature stress, while water stress had no effect on most yield components. The severe reduction of pods main shoot-1 (75%), seeds pod-1 (25%), and seed weight (22%) by 35/18 °C, reduced main stem seed yield of by 87% in all Brassica cultivars. However, seed yield reduction per plant by the same stress was 51%, indicating recovery from the stress treatments by Brassica species. Delaying exposure to stress to pod development stage reduced the chance of the plant to recover from the stress. The low water stress was to encouraging better recovery at 28/18 °C stress. In the controlled growth chamber, B. juncea cultivars responded to heat stress by increasing pod production but ignoring filling pods, while B. napus maintained a better seed fill. Under field conditions where plant-to-plant competition is strong, B. juncea may produce more pods with higher seed yield than canola; this needs to be confirmed with further field trials

Variety and topping effects of yield and quality of okra

​​A report from The University of Tennessee Extension Service indicated 9,000 acres of okra was produced in Tennessee in 1960 (9). Most of this production was channeled into the processing plants. Varieties that have proven to be adapted to Tennessee conditions and also good for processing have been limited. Recently, Emerald and Gold Coast varieties were released and showed promise in some areas as being superior to Clemson Spineless, in some respects. In order to evaluate these new varieties for yield under Tennessee conditions as well as for processing characteristics, a variety trial was conducted in 1960 using Clemson Spineless, Emerald and Gold Coast. Okra being an indeterminate plant (18) the lateral branches tend to be suppressed until the terminal buds are well advanced. This makes for s very low yield on the first several harvests since only one terminal branch on each plant fruits during this early period. Since pods must be harvested two or three times per week, this involves a great deal of hand labor with low yields each time. With several flower plants (chrysanthemum, carnation, dahlia) a practice of removing the terminal growth when the plant is quite small is used to encourage axillary branching. These axillary branches develop at a fairly uniform rate, producing several flower buds on each plant at about the same time. As a part of the variety trials, an experiment involving topping of the okra plants at various heights was initiated to determine the influence on yield by harvest periods. If several branches of each plant bore pods at the same time, this would reduce the labor required per bushel of okra harvested

Comparative Analysis of Quagi and Yagi-Uda Antenna using 4NEC2 Tool

A Yagi-Uda antenna is one of the most widely used antenna in communication. Quagi antenna is a variation on vulnerable Yagi-Uda. Both the antennas are designed using 4NEC2 tool. Comparative analysis is being done on both 8-element Yagi-Uda antenna and 8-element Quagi antenna at 432 MHz frequency. A Quagi antenna is merely one of the most interesting amateur antenna designs to come down the pike in recent years. The need for low cost, high gain antenna for Moon bounce Communication, where moon is used as Passive communication satellite, inspired the development of Quagi antenna. Since Quagi is easy and non critical construction, cheap as well as simple, matching of feed line to the driven element, makes Quagi an attractive alternate to both Quad and Yagi-Uda antennas. At 432 MHz both Quagi and Yagi-Uda give almost same efficiency and gain, but Quad loop make an excellent driven element and reflectors, rods seem to be superior directors. So doing comparative analysis on both these antennas at 432 MHz would make sense and this made me to take up this topic

Shot boundary detection in videos using Graph Cut Sets

The Shot Boundary Detection (SBD) is an early step for most of the video applications involving understanding, indexing, characterization, or categorization of video. The SBD is temporal video segmentation and it has been an active topic of research in the area of content based video analysis. The research efforts have resulted in a variety of algorithms. The major methods that have been used for shot boundary detection include pixel intensity based, histogram-based, edge-based, and motion vectors based, technique. Recently researchers have attempted use of graph theory based methods for shot boundary detection. The proposed algorithm is one such graph based model and employs graph partition mechanism for detection of shot boundaries. Graph partition model is one of the graph theoretic segmentation algorithms, which offers data clustering by using a graph model. Pair-wise similarities between all data objects are used to construct a weighted graph represented as an adjacency matrix (weighted similarity matrix) that contains all necessary information for clustering. Representing the data set in the form of an edge-weighted graph converts the data clustering problem into a graph partitioning problem. The algorithm is experimented on sports and movie videos and the results indicate the promising performance